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Sample records for samoa earthquake tsunami

  1. Damages in American Samoa due to the 29 September 2009 Samoa Islands Region Earthquake Tsunami

    Science.gov (United States)

    Okumura, Y.; Takahashi, T.; Suzuki, S.

    2009-12-01

    A large earthquake of Mw 8.0 occurred in Samoa Islands Region in the early morning on 29 September 2009 (local time). A Large Tsunami generated by the earthquake hit Samoa, American Samoa, Tonga. Total 192 people were died or missing in these three countries (22 October 2009). The authors surveyed in Tutuila Island, American Samoa from 6 to 8 in October 2009 with the aim to find out damages in the disaster. In American Samoa, death and missing toll was 35. The main findings are as follows; first, human damages were little for tsunami run-up height of about 4 to 6 meters and tsunami arrival time of about 20 minutes. We can suppose that residents evacuated quickly after feeling shaking or something. Secondly, houses were severely damaged in some low elevation coastal villages such as Amanave, Leone, Pago Pago, Tula and so on. Third, a power plant and an airport, which are important infrastructures in relief and recovery phase, were also severely damaged. Inundation depth at the power plant was 2.31 meters. A blackout in the daytime lasted when we surveyed. On the other hand, the airport could use already at that time. But it was closed on the first day in the disaster because of a lot of disaster debris on the runway carried by tsunami. Inundation depth at the airport fence was measured in 0.7 to 0.8 meters. Other countries in the south-western Pacific region may have power plants or airports with similar risk, so it should be assessed against future tsunami disasters. Inundated thermal power plant in Pago Pago Debris on runway in Tafuna Airport (Provided by Mr. Chris Soti, DPA)

  2. Factors affecting household adoption of an evacuation plan in American Samoa after the 2009 earthquake and tsunami.

    Science.gov (United States)

    Apatu, Emma J I; Gregg, Chris E; Richards, Kasie; Sorensen, Barbara Vogt; Wang, Liang

    2013-08-01

    American Samoa is still recovering from the debilitating consequences of the September 29, 2009 tsunami. Little is known about current household preparedness in American Samoa for future earthquakes and tsunamis. Thus, this study sought to enumerate the number of households with an earthquake and tsunami evacuation plan and to identify predictors of having a household evacuation plan through a post-tsunami survey conducted in July 2011. Members of 300 households were interviewed in twelve villages spread across regions of the principle island of Tutuila. Multiple logistic regression showed that being male, having lived in one's home for tsunami event increased the likelihood of having a household evacuation plan. The prevalence of tsunami evacuation planning was 35% indicating that survivors might feel that preparation is not necessary given effective adaptive responses during the 2009 event. Results suggest that emergency planners and public health officials should continue with educational outreach to families to spread awareness around the importance of developing plans for future earthquakes and tsunamis to help mitigate human and structural loss from such natural disasters. Additional research is needed to better understand the linkages between pre-event planning and effective evacuation responses as were observed in the 2009 events.

  3. Household evacuation characteristics in American Samoa during the 2009 Samoa Islands tsunami

    Science.gov (United States)

    Apatu, Emma J. I.; Gregg, Chris E.; Wood, Nathan J.; Wang, Liang

    2016-01-01

    Tsunamis represent significant threats to human life and development in coastal communities. This quantitative study examines the influence of household characteristics on evacuation actions taken by 211 respondents in American Samoa who were at their homes during the 29 September 2009 Mw 8.1 Samoa Islands earthquake and tsunami disaster. Multiple logistic regression analysis of survey data was used to examine the association between evacuation and various household factors. Findings show that increases in distance to shoreline were associated with a slightly decreased likelihood of evacuation, whereas households reporting higher income had an increased probability of evacuation. The response in American Samoa was an effective one, with only 34 fatalities in a tsunami that reached shore in as little as 15 minutes. Consequently, future research should implement more qualitative study designs to identify event and cultural specific determinants of household evacuation behaviour to local tsunamis.

  4. Survivor Interviews from the Sept. 29, 2009 tsunami on Samoa and American Samoa

    Science.gov (United States)

    Richmond, B. M.; Dudley, W. C.; Buckley, M. L.; Jaffe, B. E.; Fanolua, S.; Chan Kau, M.

    2009-12-01

    Thirty-one video interviews were carried out on the islands of Tutuila, American Samoa and Upolu, Samoa with survivors of, and responders to, the September 29, 2009 tsunami event. Those interviewed included local residents caught by the waves while attempting to flee to higher ground, those who intentionally ran into the water to save others, individuals who recognized the potential tsunami hazard due to the severity of the earthquake and attempted to warn others, first-responders, aid workers, tourism managers, and others. The frank, often emotional, responses provide unfiltered insight into the level of preparedness of local residents, level of training of first responders, and challenges faced by aid workers. Among the important observations voiced by interviewees were: (1) recent tsunami education briefings and school drills were critical in preventing greater loss of life; (2) those who had not received training about the tsunami hazard were unaware that a tsunami could follow a strong earthquake; (3) first responders were not adequately trained or prepared for the specific impacts of a tsunami; (4) initial medical procedures did not adequately address the levels of bacterial contamination; and (5) survivors, first responders and aid workers suffer from post traumatic stress disorder as a result of the event and its aftermath. Valuable scientific data can also be gained from first-hand accounts. Several interviews describe waves “bending,” “funneling,” and one spoke of the waves coming together as a “monster that jumped up from the channel spitting boulders.” In the village of Fagasa on the north coast of Tutuila, American Samoa, the assumed transport direction of large boulders by scientists was dramatically revised based on first-hand accounts of the original position of the boulders. The single most common message was that hazard education played a key role in saving lives in both Samoa and American Samoa. It is critically important to

  5. An Adjoint Sensitivity Method Applied to Time Reverse Imaging of Tsunami Source for the 2009 Samoa Earthquake

    Science.gov (United States)

    Hossen, M. Jakir; Gusman, Aditya; Satake, Kenji; Cummins, Phil R.

    2018-01-01

    We have previously developed a tsunami source inversion method based on "Time Reverse Imaging" and demonstrated that it is computationally very efficient and has the ability to reproduce the tsunami source model with good accuracy using tsunami data of the 2011 Tohoku earthquake tsunami. In this paper, we implemented this approach in the 2009 Samoa earthquake tsunami triggered by a doublet earthquake consisting of both normal and thrust faulting. Our result showed that the method is quite capable of recovering the source model associated with normal and thrust faulting. We found that the inversion result is highly sensitive to some stations that must be removed from the inversion. We applied an adjoint sensitivity method to find the optimal set of stations in order to estimate a realistic source model. We found that the inversion result is improved significantly once the optimal set of stations is used. In addition, from the reconstructed source model we estimated the slip distribution of the fault from which we successfully determined the dipping orientation of the fault plane for the normal fault earthquake. Our result suggests that the fault plane dip toward the northeast.

  6. Reconnaissance Survey of the 29 September 2009 Tsunami on Tutuila Island, American Samoa

    Science.gov (United States)

    Fritz, H. M.; Borrero, J. C.; Okal, E.; Synolakis, C.; Weiss, R.; Jaffe, B. E.; Lynett, P. J.; Titov, V. V.; Foteinis, S.; Chan, I.; Liu, P.

    2009-12-01

    On 29 September, 2009 a magnitude Mw 8.1 earthquake occurred 200 km southwest of American Samoa’s Capital of Pago Pago and triggered a tsunami which caused substantial damage and loss of life in Samoa, American Samoa and Tonga. The most recent estimate is that the tsunami caused 189 fatalities, including 34 in American Samoa. This is the highest tsunami death toll on US territory since the 1964 great Alaskan earthquake and tsunami. PTWC responded and issued warnings soon after the earthquake but, because the tsunami arrived within 15 minutes at many locations, was too late to trigger evacuations. Fortunately, the people of Samoa knew to go to high ground after an earthquake because of education and tsunami evacuation exercises initiated throughout the South Pacific after a similar magnitude earthquake and tsunami struck the nearby Solomon Islands in 2007. A multi-disciplinary reconnaissance survey team was deployed within days of the event to document flow depths, runup heights, inundation distances, sediment deposition, damage patterns at various scales, and performance of the man-made infrastructure and impact on the natural environment. The 4 to 11 October 2009 ITST circled American Samoa’s main island Tutuila and the small nearby island of Aunu’u. The American Samoa survey data includes nearly 200 runup and flow depth measurements on Tutuila Island. The tsunami impact peaked with maximum runup exceeding 17 m at Poloa located 1.5 km northeast of Cape Taputapu marking Tutuila’s west tip. A significant variation in tsunami impact was observed on Tutuila. The tsunami runup reached 12 m at Fagasa near the center of the Tutuila’s north coast and 9 m at Tula near Cape Matatula at the east end. Pago Pago, which is near the center of the south coast, represents an unfortunate example of a village and harbor that was located for protection from storm waves but is vulnerable to tsunami waves. The flow patterns inside Pago Pago harbor were characterized based on

  7. THE SAMOA TSUNAMI OF 29 SEPTEMBER 2009 Early Warning and Inundation Assessment

    Directory of Open Access Journals (Sweden)

    Giovanni Franchello

    2012-01-01

    Full Text Available On 29 September 2009 at 17:48:11 UTC, a large earthquake of magnitude 8 struck off-shore of the Samoa Islands and generated a large tsunami that destroyed several villages and caused more than 160 fatalities. This report first presents the characteristics of the earthquake and discusses the best estimations for the fault parameters, which are the necessary input data for the hydrodynamic tsunami calculations. Then, the assessment of the near-real time systems invoked by the Global Disasters Alert and Coordination System (GDACS1 and the post-event calculations are performed, making comparisons with the observed tidal measurements and post-event survey. It was found that the most severely damaged locations are the Southern section of the Western Samoa Islands, Tutuila Isl in American Samoa and Niuatoputapu Isle in Tonga. This is in agreement with the locations indicated by the Red Cross as the most affected and with the results of the post-tsunami surveys. Furthermore, an attempt was made to map the inundation events using more detailed digital elevation models (DEM and hydrodynamic modelling with good results. The flooded areas for which we had satellite images and post-tsunami surveys confirm the inundated areas identified correctly by the hydrodynamic model. Indications are given on the DEM grid size needed for the different simulations.

  8. The 2009 Samoa-Tonga great earthquake triggered doublet

    Science.gov (United States)

    Lay, T.; Ammon, C.J.; Kanamori, H.; Rivera, L.; Koper, K.D.; Hutko, Alexander R.

    2010-01-01

    Great earthquakes (having seismic magnitudes of at least 8) usually involve abrupt sliding of rock masses at a boundary between tectonic plates. Such interplate ruptures produce dynamic and static stress changes that can activate nearby intraplate aftershocks, as is commonly observed in the trench-slope region seaward of a great subduction zone thrust event1-4. The earthquake sequence addressed here involves a rare instance in which a great trench-slope intraplate earthquake triggered extensive interplate faulting, reversing the typical pattern and broadly expanding the seismic and tsunami hazard. On 29 September 2009, within two minutes of the initiation of a normal faulting event with moment magnitude 8.1 in the outer trench-slope at the northern end of the Tonga subduction zone, two major interplate underthrusting subevents (both with moment magnitude 7.8), with total moment equal to a second great earthquake of moment magnitude 8.0, ruptured the nearby subduction zone megathrust. The collective faulting produced tsunami waves with localized regions of about 12metres run-up that claimed 192 lives in Samoa, American Samoa and Tonga. Overlap of the seismic signals obscured the fact that distinct faults separated by more than 50km had ruptured with different geometries, with the triggered thrust faulting only being revealed by detailed seismic wave analyses. Extensive interplate and intraplate aftershock activity was activated over a large region of the northern Tonga subduction zone. ?? 2010 Macmillan Publishers Limited. All rights reserved.

  9. Pago Pago, American Samoa Tsunami Forecast Grids for MOST Model

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The Pago Pago, American Samoa Forecast Model Grids provides bathymetric data strictly for tsunami inundation modeling with the Method of Splitting Tsunami (MOST)...

  10. Impact of earthquake-induced tsunamis on public health

    Science.gov (United States)

    Mavroulis, Spyridon; Mavrouli, Maria; Lekkas, Efthymios; Tsakris, Athanassios

    2017-04-01

    Tsunamis are caused by rapid sea floor displacement during earthquakes, landslides and large explosive eruptions in marine environment setting. Massive amounts of sea water in the form of devastating surface waves travelling hundreds of kilometers per hour have the potential to cause extensive damage to coastal infrastructures, considerable loss of life and injury and emergence of infectious diseases (ID). This study involved an extensive and systematic literature review of 50 research publications related to public health impact of the three most devastating tsunamis of the last 12 years induced by great earthquakes, namely the 2004 Sumatra-Andaman earthquake (moment magnitude Mw 9.2), the 2009 Samoa earthquake (Mw 8.1) and the 2011 Tōhoku (Japan) earthquake (Mw 9.0) in the Indian, Western Pacific and South Pacific Oceans respectively. The inclusion criteria were literature type comprising journal articles and official reports, natural disaster type including tsunamis induced only by earthquakes, population type including humans, and outcome measure characterized by disease incidence increase. The potential post-tsunami ID are classified into 11 groups including respiratory, pulmonary, wound-related, water-borne, skin, vector-borne, eye, fecal-oral, food-borne, fungal and mite-borne ID. Respiratory infections were detected after all the above mentioned tsunamis. Wound-related, skin and water-borne ID were observed after the 2004 and 2011 tsunamis, while vector-borne, fecal-oral and eye ID were observed only after the 2004 tsunami and pulmonary, food-borne and mite-borne ID were diagnosed only after the 2011 tsunami. Based on available age and genre data, it is concluded that the most vulnerable population groups are males, children (age ≤ 15 years) and adults (age ≥ 65 years). Tetanus and pneumonia are the deadliest post-tsunami ID. The detected risk factors include (1) lowest socioeconomic conditions, poorly constructed buildings and lack of prevention

  11. Evaluation of Tsunami-HySEA for tsunami forecasting at selected locations in U.S.

    Science.gov (United States)

    Gonzalez Vida, J. M., Sr.; Ortega, S.; Castro, M. J.; de la Asuncion, M.; Arcas, D.

    2017-12-01

    The GPU-based Tsunami-HySEA model (Macias, J. et al., Pure and Applied Geophysics, 1-37, 2017, Lynett, P. et al., Ocean modeling, 114, 2017) is used to test four tsunami events: the January, 13, 2007 earthquake in Kuril islands (Mw 8.1), the September, 29, 2009 earthquake in Samoa (Mw 8.3), the February, 27, 2010 earthquake in Chile (Mw 9.8) and the March, 11, 2011 earthquake in Tohoku (Mw 9.0). Initial conditions have been provided by NOAA Center for Tsunami Research (NCTR) obtained from DART inversion results. All simulations have been performed using a global 4 arc-min grid of the Ocean Pacific and three nested-meshes levels around the selected locations. Wave amplitudes time series have been computed at selected tide gauges located at each location and maximum amplitudes compared with both MOST model results and observations where they are available. In addition, inundation also has been computed at selected U.S. locations for the 2011 Tohoku and 2009 Samoa events under the assumption of a steady mean high water level. Finally, computational time is also evaluated in order to study the operational capabilities of Tsunami-HySEA for these kind of events. Ackowledgements: This work has been funded by WE133R16SE1418 contract between PMEL (NOAA) and the Universidad de Málaga (Spain).

  12. Preliminary assessment of the impacts and effects of the South Pacific tsunami of September 2009 in Samoa

    Science.gov (United States)

    Dominey-Howes, D.

    2009-12-01

    The September 2009 tsunami was a regional South Pacific event of enormous significance. Our UNESCO-IOC ITST Samoa survey used a simplified version of a ‘coupled human-environment systems framework’ (Turner et al., 2003) to investigate the impacts and effects of the tsunami in Samoa. Further, the framework allowed us to identify those factors that affected the vulnerability and resilience of the human-environment system before, during and after the tsunami - a global first. Key findings (unprocessed) include: Maximum run-up exceeded 14 metres above sea level Maximum inundation (at right angles to the shore) was approximately 400 metres Maximum inundation with the wave running parallel with the shore (but inland), exceeded 700 metres Buildings sustained varying degrees of damage Damage was correlated with depth of tsunami flow, velocity, condition of foundations, quality of building materials used, quality of workmanship, adherence to the building code and so on Buildings raised even one metre above the surrounding land surface suffered much less damage Plants, trees and mangroves reduced flow velocity and flow depth - leading to greater chances of human survival and lower levels of building damage The tsunami has left a clear and distinguishable geological record in terms of sediments deposited in the coastal landscape The clear sediment layer associated with this tsunami suggests that older (and prehistoric) tsunamis can be identified, helping to answer questions about frequency and magnitude of tsunamis The tsunami caused widespread erosion of the coastal and beach zones but this damage will repair itself naturally and quickly The tsunami has had clear impacts on ecosystems and these are highly variable Ecosystems will repair themselves naturally and are unlikely to preserve long-term impacts It is clear that some plant (tree) species are highly resilient and provided immediate places for safety during the tsunami and resources post-tsunami People of Samoa are

  13. Preliminary Report Summarizes Tsunami Impacts and Lessons Learned from the September 7, 2017, M8.1 Tehuantepec Earthquake

    Science.gov (United States)

    Wilson, R. I.; Ramirez-Herrera, M. T.; Dengler, L. A.; Miller, K.; LaDuke, Y.

    2017-12-01

    The preliminary tsunami impacts from the September 7, 2017, M8.1 Tehuantepec Earthquake have been summarized in the following report: https://www.eeri.org/wp-content/uploads/EERI-Recon-Rpt-090717-Mexico-tsunami_fn.pdf. Although the tsunami impacts were not as significant as those from the earthquake itself (98 fatalities and 41,000 homes damaged), the following are highlights and lessons learned: The Tehuantepec earthquake was one of the largest down-slab normal faulting events ever recorded. This situation complicated the tsunami forecast since forecast methods and pre-event modeling are primarily associated with megathrust earthquakes where the most significant tsunamis are generated. Adding non-megathrust source modeling to the tsunami forecast databases of conventional warning systems should be considered. Offshore seismic and tsunami hazard analyses using past events should incorporate the potential for large earthquakes occurring along sources other than the megathrust boundary. From an engineering perspective, initial reports indicate there was only minor tsunami damage along the Mexico coast. There was damage to Marina Chiapas where floating docks overtopped their piles. Increasing pile heights could reduce the potential for damage to floating docks. Tsunami warning notifications did not get to the public in time to assist with evacuation. Streamlining the messaging in Mexico from the warning system directly to the public should be considered. And, for local events, preparedness efforts should place emphasis on responding to feeling the earthquake and not waiting to be notified. Although the U.S. tsunami warning centers were timely with their international and domestic messaging, there were some issues with how those messages were presented and interpreted. The use of a "Tsunami Threat" banner on the new main warning center website created confusion with emergency managers in the U.S. where no tsunami threat was expected to exist. Also, some U.S. states and

  14. Public Health Needs Assessments of Tutuila Island, American Samoa, After the 2009 Tsunami

    Science.gov (United States)

    Choudhary, Ekta; Chen, Tai-Ho; Martin, Colleen; Vagi, Sara; Roth, Joseph; Keim, Mark; Noe, Rebecca; Ponausuia, Seiuli Elisapeta; Lemusu, Siitia; Bayleyegn, Tesfaye; Wolkin, Amy

    2015-01-01

    Objective An 8.3 magnitude earthquake followed by tsunami waves devastated American Samoa on September 29, 2009, resulting in widespread loss of property and public services. An initial and a follow-up Community Needs Assessment for Public Health Emergency Response (CASPER) objectively quantified disaster-affected population needs. Methods Using a 2-stage cluster sampling method of CASPER, a household questionnaire eliciting information about medical and basic needs, illnesses, and injuries was administered. To assess response efforts, percent changes in basic and medical needs, illnesses, and injuries between the initial and follow-up CASPER were calculated. Results During the initial CASPER (N=212 households), 47.6% and 51.6% of households reported needing a tarpaulin and having no electricity, respectively. The self-reported greatest needs were water (27.8%) and financial help with cleanup (25.5%). The follow-up CASPER (N=207 households) identified increased vector problems compared to pre-tsunami, and food (26%) was identified as the self-reported greatest need. As compared to the initial CASPER, the follow-up CASPER observed decreases in electricity (−78.3%), drinking water (−44.4%), and clothing (−26.6%). Conclusion This study highlights the use of CASPER during the response and recovery phases following a disaster. The initial CASPER identified basic needs immediately after the earthquake, whereas the follow-up CASPER assessed effectiveness of relief efforts and identified ongoing community needs. PMID:23077263

  15. The Pacific Tsunami Warning Center's Response to the Tohoku Earthquake and Tsunami

    Science.gov (United States)

    Weinstein, S. A.; Becker, N. C.; Shiro, B.; Koyanagi, K. K.; Sardina, V.; Walsh, D.; Wang, D.; McCreery, C. S.; Fryer, G. J.; Cessaro, R. K.; Hirshorn, B. F.; Hsu, V.

    2011-12-01

    The largest Pacific basin earthquake in 47 years, and also the largest magnitude earthquake since the Sumatra 2004 earthquake, struck off of the east coast of the Tohoku region of Honshu, Japan at 5:46 UTC on 11 March 2011. The Tohoku earthquake (Mw 9.0) generated a massive tsunami with runups of up to 40m along the Tohoku coast. The tsunami waves crossed the Pacific Ocean causing significant damage as far away as Hawaii, California, and Chile, thereby becoming the largest, most destructive tsunami in the Pacific Basin since 1960. Triggers on the seismic stations at Erimo, Hokkaido (ERM) and Matsushiro, Honshu (MAJO), alerted Pacific Tsunami Warning Center (PTWC) scientists 90 seconds after the earthquake began. Four minutes after its origin, and about one minute after the earthquake's rupture ended, PTWC issued an observatory message reporting a preliminary magnitude of 7.5. Eight minutes after origin time, the Japan Meteorological Agency (JMA) issued its first international tsunami message in its capacity as the Northwest Pacific Tsunami Advisory Center. In accordance with international tsunami warning system protocols, PTWC then followed with its first international tsunami warning message using JMA's earthquake parameters, including an Mw of 7.8. Additional Mwp, mantle wave, and W-phase magnitude estimations based on the analysis of later-arriving seismic data at PTWC revealed that the earthquake magnitude reached at least 8.8, and that a destructive tsunami would likely be crossing the Pacific Ocean. The earthquake damaged the nearest coastal sea-level station located 90 km from the epicenter in Ofunato, Japan. The NOAA DART sensor situated 600 km off the coast of Sendai, Japan, at a depth of 5.6 km recorded a tsunami wave amplitude of nearly two meters, making it by far the largest tsunami wave ever recorded by a DART sensor. Thirty minutes later, a coastal sea-level station at Hanasaki, Japan, 600 km from the epicenter, recorded a tsunami wave amplitude of

  16. Method to Determine Appropriate Source Models of Large Earthquakes Including Tsunami Earthquakes for Tsunami Early Warning in Central America

    Science.gov (United States)

    Tanioka, Yuichiro; Miranda, Greyving Jose Arguello; Gusman, Aditya Riadi; Fujii, Yushiro

    2017-08-01

    Large earthquakes, such as the Mw 7.7 1992 Nicaragua earthquake, have occurred off the Pacific coasts of El Salvador and Nicaragua in Central America and have generated distractive tsunamis along these coasts. It is necessary to determine appropriate fault models before large tsunamis hit the coast. In this study, first, fault parameters were estimated from the W-phase inversion, and then an appropriate fault model was determined from the fault parameters and scaling relationships with a depth dependent rigidity. The method was tested for four large earthquakes, the 1992 Nicaragua tsunami earthquake (Mw7.7), the 2001 El Salvador earthquake (Mw7.7), the 2004 El Astillero earthquake (Mw7.0), and the 2012 El Salvador-Nicaragua earthquake (Mw7.3), which occurred off El Salvador and Nicaragua in Central America. The tsunami numerical simulations were carried out from the determined fault models. We found that the observed tsunami heights, run-up heights, and inundation areas were reasonably well explained by the computed ones. Therefore, our method for tsunami early warning purpose should work to estimate a fault model which reproduces tsunami heights near the coast of El Salvador and Nicaragua due to large earthquakes in the subduction zone.

  17. Ionospheric detection of tsunami earthquakes: observation, modeling and ideas for future early warning

    Science.gov (United States)

    Occhipinti, G.; Manta, F.; Rolland, L.; Watada, S.; Makela, J. J.; Hill, E.; Astafieva, E.; Lognonne, P. H.

    2017-12-01

    Detection of ionospheric anomalies following the Sumatra and Tohoku earthquakes (e.g., Occhipinti 2015) demonstrated that ionosphere is sensitive to earthquake and tsunami propagation: ground and oceanic vertical displacement induces acoustic-gravity waves propagating within the neutral atmosphere and detectable in the ionosphere. Observations supported by modelling proved that ionospheric anomalies related to tsunamis are deterministic and reproducible by numerical modeling via the ocean/neutral-atmosphere/ionosphere coupling mechanism (Occhipinti et al., 2008). To prove that the tsunami signature in the ionosphere is routinely detected we show here perturbations of total electron content (TEC) measured by GPS and following tsunamigenic earthquakes from 2004 to 2011 (Rolland et al. 2010, Occhipinti et al., 2013), nominally, Sumatra (26 December, 2004 and 12 September, 2007), Chile (14 November, 2007), Samoa (29 September, 2009) and the recent Tohoku-Oki (11 Mars, 2011). Based on the observations close to the epicenter, mainly performed by GPS networks located in Sumatra, Chile and Japan, we highlight the TEC perturbation observed within the first 8 min after the seismic rupture. This perturbation contains information about the ground displacement, as well as the consequent sea surface displacement resulting in the tsunami. In addition to GNSS-TEC observations close to the epicenter, new exciting measurements in the far-field were performed by airglow measurement in Hawaii show the propagation of the internal gravity waves induced by the Tohoku tsunami (Occhipinti et al., 2011). This revolutionary imaging technique is today supported by two new observations of moderate tsunamis: Queen Charlotte (M: 7.7, 27 October, 2013) and Chile (M: 8.2, 16 September 2015). We finally detail here our recent work (Manta et al., 2017) on the case of tsunami alert failure following the Mw7.8 Mentawai event (25 October, 2010), and its twin tsunami alert response following the Mw7

  18. Effect of earthquake and tsunami. Ground motion and tsunami observed at nuclear power station

    International Nuclear Information System (INIS)

    Hijikata, Katsuichirou

    2012-01-01

    Fukushima Daiichi and Daini Nuclear Power Stations (NPSs) were struck by the earthquake off the pacific coast in the Tohoku District, which occurred at 14:46 on March 11, 2011. Afterwards, tsunamis struck the Tohoku District. In terms of the earthquake observed at the Fukushima NPSs, the acceleration response spectra of the earthquake movement observed on the basic board of reactor buildings exceeded the acceleration response spectra of the response acceleration to the standard seismic ground motion Ss for partial periodic bands at the Fukushima Daiichi NPS. As for the Fukushima Daini NPS, the acceleration response spectra of the earthquake movement observed on the basic board of the reactor buildings was below the acceleration response spectra of the response acceleration to the standard seismic ground motion Ss. Areas inundated by Tsunami at each NPS were investigated and tsunami inversion analysis was made to build tsunami source model to reproduce tide record, tsunami height, crustal movement and inundated area, based on tsunami observation records in the wide areas from Hokkaido to Chiba prefectures. Tsunami heights of Fukushima Daiichi and Daini NPSs were recalculated as O.P. +13m and +9m respectively and tsunami peak height difference was attributed to the extent of superposition of tsunami waves of tsunami earthquake type of wave source in the area along interplane trench off the coast in the Fukushima prefecture and interplane earthquake type of wave source in rather deep interplate area off the coast in the Miyagi prefecture. (T. Tanaka)

  19. The Limit of Inundation of the September 29, 2009, Tsunami on Tutuila, American Samoa

    Science.gov (United States)

    Jaffe, Bruce E.; Gelfenbaum, Guy; Buckley, Mark L.; Watt, Steve; Apotsos, Alex; Stevens, Andrew W.; Richmond, Bruce M.

    2010-01-01

    U.S. Geological Survey scientists investigated the coastal impacts of the September 29, 2009, South Pacific tsunami in Tutuila, American Samoa in October and November 2009, including mapping the alongshore variation in the limit of inundation. Knowing the inundation limit is useful for planning safer coastal development and evacuation routes for future tsunamis and for improving models of tsunami hazards. This report presents field data documenting the limit of inundation at 18 sites around Tutuila collected in the weeks following the tsunami using Differential GPS (DGPS). In total, 15,703 points along inundation lines were mapped. Estimates of DGPS error and uncertainty in interpretation of the inundation line are provided as electronic files that accompany this report.

  20. Mexican Earthquakes and Tsunamis Catalog Reviewed

    Science.gov (United States)

    Ramirez-Herrera, M. T.; Castillo-Aja, R.

    2015-12-01

    Today the availability of information on the internet makes online catalogs very easy to access by both scholars and the public in general. The catalog in the "Significant Earthquake Database", managed by the National Center for Environmental Information (NCEI formerly NCDC), NOAA, allows access by deploying tabular and cartographic data related to earthquakes and tsunamis contained in the database. The NCEI catalog is the product of compiling previously existing catalogs, historical sources, newspapers, and scientific articles. Because NCEI catalog has a global coverage the information is not homogeneous. Existence of historical information depends on the presence of people in places where the disaster occurred, and that the permanence of the description is preserved in documents and oral tradition. In the case of instrumental data, their availability depends on the distribution and quality of seismic stations. Therefore, the availability of information for the first half of 20th century can be improved by careful analysis of the available information and by searching and resolving inconsistencies. This study shows the advances we made in upgrading and refining data for the earthquake and tsunami catalog of Mexico since 1500 CE until today, presented in the format of table and map. Data analysis allowed us to identify the following sources of error in the location of the epicenters in existing catalogs: • Incorrect coordinate entry • Place name erroneous or mistaken • Too general data that makes difficult to locate the epicenter, mainly for older earthquakes • Inconsistency of earthquakes and the tsunami occurrence: earthquake's epicenter located too far inland reported as tsunamigenic. The process of completing the catalogs directly depends on the availability of information; as new archives are opened for inspection, there are more opportunities to complete the history of large earthquakes and tsunamis in Mexico. Here, we also present new earthquake and

  1. Comparison of Human Response against Earthquake and Tsunami

    Science.gov (United States)

    Arikawa, T.; Güler, H. G.; Yalciner, A. C.

    2017-12-01

    The evacuation response against the earthquake and tsunamis is very important for the reduction of human damages against tsunami. But it is very difficult to predict the human behavior after shaking of the earthquake. The purpose of this research is to clarify the difference of the human response after the earthquake shock in the difference countries and to consider the relation between the response and the safety feeling, knowledge and education. For the objective of this paper, the questionnaire survey was conducted after the 21st July 2017 Gokova earthquake and tsunami. Then, consider the difference of the human behavior by comparison of that in 2015 Chilean earthquake and tsunami and 2011 Japan earthquake and tsunami. The seismic intensity of the survey points was almost 6 to 7. The contents of the questions include the feeling of shaking, recalling of the tsunami, the behavior after shock and so on. The questionnaire was conducted for more than 20 20 people in 10 areas. The results are the following; 1) Most people felt that it was a strong shake not to stand, 2) All of the questionnaires did not recall the tsunami, 3) Depending on the area, they felt that after the earthquake the beach was safer than being at home. 4) After they saw the sea drawing, they thought that a tsunami would come and ran away. Fig. 1 shows the comparison of the evacuation rate within 10 minutes in 2011 Japan, 2015 Chile and 2017 Turkey.. From the education point of view, education for tsunami is not done much in Turkey. From the protection facilities point of view, the high sea walls are constructed only in Japan. From the warning alert point of view, there is no warning system against tsunamis in the Mediterranean Sea. As a result of this survey, the importance of tsunami education is shown, and evacuation tends to be delayed if dependency on facilities and alarms is too high.

  2. Tsunami evacuation plans for future megathrust earthquakes in Padang, Indonesia, considering stochastic earthquake scenarios

    Directory of Open Access Journals (Sweden)

    A. Muhammad

    2017-12-01

    Full Text Available This study develops tsunami evacuation plans in Padang, Indonesia, using a stochastic tsunami simulation method. The stochastic results are based on multiple earthquake scenarios for different magnitudes (Mw 8.5, 8.75, and 9.0 that reflect asperity characteristics of the 1797 historical event in the same region. The generation of the earthquake scenarios involves probabilistic models of earthquake source parameters and stochastic synthesis of earthquake slip distributions. In total, 300 source models are generated to produce comprehensive tsunami evacuation plans in Padang. The tsunami hazard assessment results show that Padang may face significant tsunamis causing the maximum tsunami inundation height and depth of 15 and 10 m, respectively. A comprehensive tsunami evacuation plan – including horizontal evacuation area maps, assessment of temporary shelters considering the impact due to ground shaking and tsunami, and integrated horizontal–vertical evacuation time maps – has been developed based on the stochastic tsunami simulation results. The developed evacuation plans highlight that comprehensive mitigation policies can be produced from the stochastic tsunami simulation for future tsunamigenic events.

  3. Nonlinear wave runup in long bays and firths: Samoa 2009 and Tohoku 2011 tsunamis

    Science.gov (United States)

    Didenkulova, I.; Pelinovsky, E.

    2012-04-01

    Last catastrophic tsunami events in Samoa on 29 September 2009 and in Japan on 11 March 2011 demonstrated that tsunami may experience abnormal amplification in long bays and firths and result in an unexpectedly high wave runup. The capital city Pago Pago, which is located at the toe of a narrow 4-km-long bay and represents the most characteristic example of a long and narrow bay, was considerably damaged during Samoa 2009 tsunami (destroyed infrastructures, boats and shipping containers carried inland into commercial areas, etc.) The runup height there reached 8 m over an inundation of 538 m at its toe, while the tsunami wave height measured by the tide-gauge at the entrance of the bay was at most 3 m. The same situation was observed during catastrophic Tohoku tsunami in Japan, which coast contains numerous long bays and firths, which experienced the highest wave runup and the strongest amplification. Such examples are villages: Ofunato, Ryori Bay, where the wave runup reached 30 m high, and Onagawa, where the wave amplified up to 17 m. Here we study the nonlinear dynamics of tsunami waves in an inclined U-shaped bay. Nonlinear shallow water equations can in this case be written in 1D form and solved analytically with the use of the hodograph transformation. This approach generalizes the well-known Carrier-Greenspan transformation for long wave runup on a plane beach. In the case of an inclined U-shaped bay it leads to the associated generalized wave equation for symmetrical wave in fractal space. In the special case of the channel of parabolic cross-section it is a spherical symmetrical linear wave equation. As a result, the solution of the Cauchy problem can be expressed in terms of elementary functions and has a simple form (with respect to analysis) for any kind of initial conditions. Wave regimes associated with various localized initial conditions, corresponding to problems of evolution and runup of tsunami, are considered and analyzed. Special attention is

  4. Seismogeodesy for rapid earthquake and tsunami characterization

    Science.gov (United States)

    Bock, Y.

    2016-12-01

    Rapid estimation of earthquake magnitude and fault mechanism is critical for earthquake and tsunami warning systems. Traditionally, the monitoring of earthquakes and tsunamis has been based on seismic networks for estimating earthquake magnitude and slip, and tide gauges and deep-ocean buoys for direct measurement of tsunami waves. These methods are well developed for ocean basin-wide warnings but are not timely enough to protect vulnerable populations and infrastructure from the effects of local tsunamis, where waves may arrive within 15-30 minutes of earthquake onset time. Direct measurements of displacements by GPS networks at subduction zones allow for rapid magnitude and slip estimation in the near-source region, that are not affected by instrumental limitations and magnitude saturation experienced by local seismic networks. However, GPS displacements by themselves are too noisy for strict earthquake early warning (P-wave detection). Optimally combining high-rate GPS and seismic data (in particular, accelerometers that do not clip), referred to as seismogeodesy, provides a broadband instrument that does not clip in the near field, is impervious to magnitude saturation, and provides accurate real-time static and dynamic displacements and velocities in real time. Here we describe a NASA-funded effort to integrate GPS and seismogeodetic observations as part of NOAA's Tsunami Warning Centers in Alaska and Hawaii. It consists of a series of plug-in modules that allow for a hierarchy of rapid seismogeodetic products, including automatic P-wave picking, hypocenter estimation, S-wave prediction, magnitude scaling relationships based on P-wave amplitude (Pd) and peak ground displacement (PGD), finite-source CMT solutions and fault slip models as input for tsunami warnings and models. For the NOAA/NASA project, the modules are being integrated into an existing USGS Earthworm environment, currently limited to traditional seismic data. We are focused on a network of

  5. The 2010 Chile Earthquake: Rapid Assessments of Tsunami

    OpenAIRE

    Michelini, A.; Lauciani, V.; Selvaggi, G.; Lomax, A.

    2010-01-01

    After an earthquake underwater, rapid real-time assessment of earthquake parameters is important for emergency response related to infrastructure damage and, perhaps more exigently, for issuing warnings of the possibility of an impending tsunami. Since 2005, the Istituto Nazionale di Geofisica e Vulcanologia (INGV) has worked on the rapid quantification of earthquake magnitude and tsunami potential, especially for the Mediterranean area. This work includes quantification of earthquake size fr...

  6. Tsunami hazard assessments with consideration of uncertain earthquakes characteristics

    Science.gov (United States)

    Sepulveda, I.; Liu, P. L. F.; Grigoriu, M. D.; Pritchard, M. E.

    2017-12-01

    The uncertainty quantification of tsunami assessments due to uncertain earthquake characteristics faces important challenges. First, the generated earthquake samples must be consistent with the properties observed in past events. Second, it must adopt an uncertainty propagation method to determine tsunami uncertainties with a feasible computational cost. In this study we propose a new methodology, which improves the existing tsunami uncertainty assessment methods. The methodology considers two uncertain earthquake characteristics, the slip distribution and location. First, the methodology considers the generation of consistent earthquake slip samples by means of a Karhunen Loeve (K-L) expansion and a translation process (Grigoriu, 2012), applicable to any non-rectangular rupture area and marginal probability distribution. The K-L expansion was recently applied by Le Veque et al. (2016). We have extended the methodology by analyzing accuracy criteria in terms of the tsunami initial conditions. Furthermore, and unlike this reference, we preserve the original probability properties of the slip distribution, by avoiding post sampling treatments such as earthquake slip scaling. Our approach is analyzed and justified in the framework of the present study. Second, the methodology uses a Stochastic Reduced Order model (SROM) (Grigoriu, 2009) instead of a classic Monte Carlo simulation, which reduces the computational cost of the uncertainty propagation. The methodology is applied on a real case. We study tsunamis generated at the site of the 2014 Chilean earthquake. We generate earthquake samples with expected magnitude Mw 8. We first demonstrate that the stochastic approach of our study generates consistent earthquake samples with respect to the target probability laws. We also show that the results obtained from SROM are more accurate than classic Monte Carlo simulations. We finally validate the methodology by comparing the simulated tsunamis and the tsunami records for

  7. Assessment of earthquake-induced tsunami hazard at a power plant site

    International Nuclear Information System (INIS)

    Ghosh, A.K.

    2008-01-01

    This paper presents a study of the tsunami hazard due to submarine earthquakes at a power plant site on the east coast of India. The paper considers various sources of earthquakes from the tectonic information, and records of past earthquakes and tsunamis. Magnitude-frequency relationship for earthquake occurrence rate and a simplified model for tsunami run-up height as a function of earthquake magnitude and the distance between the source and site have been developed. Finally, considering equal likelihood of generation of earthquakes anywhere on each of the faults, the tsunami hazard has been evaluated and presented as a relationship between tsunami height and its mean recurrence interval (MRI). Probability of exceedence of a certain wave height in a given period of time is also presented. These studies will be helpful in making an estimate of the tsunami-induced flooding potential at the site

  8. Tsunami Source Modeling of the 2015 Volcanic Tsunami Earthquake near Torishima, South of Japan

    Science.gov (United States)

    Sandanbata, O.; Watada, S.; Satake, K.; Fukao, Y.; Sugioka, H.; Ito, A.; Shiobara, H.

    2017-12-01

    An abnormal earthquake occurred at a submarine volcano named Smith Caldera, near Torishima Island on the Izu-Bonin arc, on May 2, 2015. The earthquake, which hereafter we call "the 2015 Torishima earthquake," has a CLVD-type focal mechanism with a moderate seismic magnitude (M5.7) but generated larger tsunami waves with an observed maximum height of 50 cm at Hachijo Island [JMA, 2015], so that the earthquake can be regarded as a "tsunami earthquake." In the region, similar tsunami earthquakes were observed in 1984, 1996 and 2006, but their physical mechanisms are still not well understood. Tsunami waves generated by the 2015 earthquake were recorded by an array of ocean bottom pressure (OBP) gauges, 100 km northeastern away from the epicenter. The waves initiated with a small downward signal of 0.1 cm and reached peak amplitude (1.5-2.0 cm) of leading upward signals followed by continuous oscillations [Fukao et al., 2016]. For modeling its tsunami source, or sea-surface displacement, we perform tsunami waveform simulations, and compare synthetic and observed waveforms at the OBP gauges. The linear Boussinesq equations are adapted with the tsunami simulation code, JAGURS [Baba et al., 2015]. We first assume a Gaussian-shaped sea-surface uplift of 1.0 m with a source size comparable to Smith Caldera, 6-7 km in diameter. By shifting source location around the caldera, we found the uplift is probably located within the caldera rim, as suggested by Sandanbata et al. [2016]. However, synthetic waves show no initial downward signal that was observed at the OBP gauges. Hence, we add a ring of subsidence surrounding the main uplift, and examine sizes and amplitudes of the main uplift and the subsidence ring. As a result, the model of a main uplift of around 1.0 m with a radius of 4 km surrounded by a ring of small subsidence shows good agreement of synthetic and observed waveforms. The results yield two implications for the deformation process that help us to understanding

  9. Tsunami Prediction and Earthquake Parameters Estimation in the Red Sea

    KAUST Repository

    Sawlan, Zaid A

    2012-12-01

    Tsunami concerns have increased in the world after the 2004 Indian Ocean tsunami and the 2011 Tohoku tsunami. Consequently, tsunami models have been developed rapidly in the last few years. One of the advanced tsunami models is the GeoClaw tsunami model introduced by LeVeque (2011). This model is adaptive and consistent. Because of different sources of uncertainties in the model, observations are needed to improve model prediction through a data assimilation framework. Model inputs are earthquake parameters and topography. This thesis introduces a real-time tsunami forecasting method that combines tsunami model with observations using a hybrid ensemble Kalman filter and ensemble Kalman smoother. The filter is used for state prediction while the smoother operates smoothing to estimate the earthquake parameters. This method reduces the error produced by uncertain inputs. In addition, state-parameter EnKF is implemented to estimate earthquake parameters. Although number of observations is small, estimated parameters generates a better tsunami prediction than the model. Methods and results of prediction experiments in the Red Sea are presented and the prospect of developing an operational tsunami prediction system in the Red Sea is discussed.

  10. Method to Determine Appropriate Source Models of Large Earthquakes Including Tsunami Earthquakes for Tsunami Early Warning in Central America

    OpenAIRE

    Tanioka, Yuichiro; Miranda, Greyving Jose Arguello; Gusman, Aditya Riadi; Fujii, Yushiro

    2017-01-01

    Large earthquakes, such as the Mw 7.7 1992 Nicaragua earthquake, have occurred off the Pacific coasts of El Salvador and Nicaragua in Central America and have generated distractive tsunamis along these coasts. It is necessary to determine appropriate fault models before large tsunamis hit the coast. In this study, first, fault parameters were estimated from the W-phase inversion, and then an appropriate fault model was determined from the fault parameters and scaling relationships with a dept...

  11. Mechanism of the 2015 volcanic tsunami earthquake near Torishima, Japan

    Science.gov (United States)

    Satake, Kenji

    2018-01-01

    Tsunami earthquakes are a group of enigmatic earthquakes generating disproportionally large tsunamis relative to seismic magnitude. These events occur most typically near deep-sea trenches. Tsunami earthquakes occurring approximately every 10 years near Torishima on the Izu-Bonin arc are another example. Seismic and tsunami waves from the 2015 event [Mw (moment magnitude) = 5.7] were recorded by an offshore seafloor array of 10 pressure gauges, ~100 km away from the epicenter. We made an array analysis of dispersive tsunamis to locate the tsunami source within the submarine Smith Caldera. The tsunami simulation from a large caldera-floor uplift of ~1.5 m with a small peripheral depression yielded waveforms remarkably similar to the observations. The estimated central uplift, 1.5 m, is ~20 times larger than that inferred from the seismologically determined non–double-couple source. Thus, the tsunami observation is not compatible with the published seismic source model taken at face value. However, given the indeterminacy of Mzx, Mzy, and M{tensile} of a shallow moment tensor source, it may be possible to find a source mechanism with efficient tsunami but inefficient seismic radiation that can satisfactorily explain both the tsunami and seismic observations, but this question remains unresolved. PMID:29740604

  12. Tsunamigenic Ratio of the Pacific Ocean earthquakes and a proposal for a Tsunami Index

    Directory of Open Access Journals (Sweden)

    A. Suppasri

    2012-01-01

    Full Text Available The Pacific Ocean is the location where two-thirds of tsunamis have occurred, resulting in a great number of casualties. Once information on an earthquake has been issued, it is important to understand if there is a tsunami generation risk in relation with a specific earthquake magnitude or focal depth. This study proposes a Tsunamigenic Ratio (TR that is defined as the ratio between the number of earthquake-generated tsunamis and the total number of earthquakes. Earthquake and tsunami data used in this study were selected from a database containing tsunamigenic earthquakes from prior 1900 to 2011. The TR is calculated from earthquake events with a magnitude greater than 5.0, a focal depth shallower than 200 km and a sea depth less than 7 km. The results suggest that a great earthquake magnitude and a shallow focal depth have a high potential to generate tsunamis with a large tsunami height. The average TR in the Pacific Ocean is 0.4, whereas the TR for specific regions of the Pacific Ocean varies from 0.3 to 0.7. The TR calculated for each region shows the relationship between three influential parameters: earthquake magnitude, focal depth and sea depth. The three parameters were combined and proposed as a dimensionless parameter called the Tsunami Index (TI. TI can express better relationship with the TR and with maximum tsunami height, while the three parameters mentioned above cannot. The results show that recent submarine earthquakes had a higher potential to generate a tsunami with a larger tsunami height than during the last century. A tsunami is definitely generated if the TI is larger than 7.0. The proposed TR and TI will help ascertain the tsunami generation risk of each earthquake event based on a statistical analysis of the historical data and could be an important decision support tool during the early tsunami warning stage.

  13. Probabilistic Tsunami Hazard Analysis of the Pacific Coast of Mexico: Case Study Based on the 1995 Colima Earthquake Tsunami

    Directory of Open Access Journals (Sweden)

    Nobuhito Mori

    2017-06-01

    Full Text Available This study develops a novel computational framework to carry out probabilistic tsunami hazard assessment for the Pacific coast of Mexico. The new approach enables the consideration of stochastic tsunami source scenarios having variable fault geometry and heterogeneous slip that are constrained by an extensive database of rupture models for historical earthquakes around the world. The assessment focuses upon the 1995 Jalisco–Colima Earthquake Tsunami from a retrospective viewpoint. Numerous source scenarios of large subduction earthquakes are generated to assess the sensitivity and variability of tsunami inundation characteristics of the target region. Analyses of nine slip models along the Mexican Pacific coast are performed, and statistical characteristics of slips (e.g., coherent structures of slip spectra are estimated. The source variability allows exploring a wide range of tsunami scenarios for a moment magnitude (Mw 8 subduction earthquake in the Mexican Pacific region to conduct thorough sensitivity analyses and to quantify the tsunami height variability. The numerical results indicate a strong sensitivity of maximum tsunami height to major slip locations in the source and indicate major uncertainty at the first peak of tsunami waves.

  14. Sensitivity of tsunami wave profiles and inundation simulations to earthquake slip and fault geometry for the 2011 Tohoku earthquake

    KAUST Repository

    Goda, Katsuichiro; Mai, Paul Martin; Yasuda, Tomohiro; Mori, Nobuhito

    2014-01-01

    In this study, we develop stochastic random-field slip models for the 2011 Tohoku earthquake and conduct a rigorous sensitivity analysis of tsunami hazards with respect to the uncertainty of earthquake slip and fault geometry. Synthetic earthquake slip distributions generated from the modified Mai-Beroza method captured key features of inversion-based source representations of the mega-thrust event, which were calibrated against rich geophysical observations of this event. Using original and synthesised earthquake source models (varied for strike, dip, and slip distributions), tsunami simulations were carried out and the resulting variability in tsunami hazard estimates was investigated. The results highlight significant sensitivity of the tsunami wave profiles and inundation heights to the coastal location and the slip characteristics, and indicate that earthquake slip characteristics are a major source of uncertainty in predicting tsunami risks due to future mega-thrust events.

  15. Sensitivity of tsunami wave profiles and inundation simulations to earthquake slip and fault geometry for the 2011 Tohoku earthquake

    KAUST Repository

    Goda, Katsuichiro

    2014-09-01

    In this study, we develop stochastic random-field slip models for the 2011 Tohoku earthquake and conduct a rigorous sensitivity analysis of tsunami hazards with respect to the uncertainty of earthquake slip and fault geometry. Synthetic earthquake slip distributions generated from the modified Mai-Beroza method captured key features of inversion-based source representations of the mega-thrust event, which were calibrated against rich geophysical observations of this event. Using original and synthesised earthquake source models (varied for strike, dip, and slip distributions), tsunami simulations were carried out and the resulting variability in tsunami hazard estimates was investigated. The results highlight significant sensitivity of the tsunami wave profiles and inundation heights to the coastal location and the slip characteristics, and indicate that earthquake slip characteristics are a major source of uncertainty in predicting tsunami risks due to future mega-thrust events.

  16. Numerical experiment on tsunami deposit distribution process by using tsunami sediment transport model in historical tsunami event of megathrust Nankai trough earthquake

    Science.gov (United States)

    Imai, K.; Sugawara, D.; Takahashi, T.

    2017-12-01

    A large flow caused by tsunami transports sediments from beach and forms tsunami deposits in land and coastal lakes. A tsunami deposit has been found in their undisturbed on coastal lakes especially. Okamura & Matsuoka (2012) found some tsunami deposits in the field survey of coastal lakes facing to the Nankai trough, and tsunami deposits due to the past eight Nankai Trough megathrust earthquakes they identified. The environment in coastal lakes is stably calm and suitable for tsunami deposits preservation compared to other topographical conditions such as plains. Therefore, there is a possibility that the recurrence interval of megathrust earthquakes and tsunamis will be discussed with high resolution. In addition, it has been pointed out that small events that cannot be detected in plains could be separated finely (Sawai, 2012). Various aspects of past tsunami is expected to be elucidated, in consideration of topographical conditions of coastal lakes by using the relationship between the erosion-and-sedimentation process of the lake bottom and the external force of tsunami. In this research, numerical examination based on tsunami sediment transport model (Takahashi et al., 1999) was carried out on the site Ryujin-ike pond of Ohita, Japan where tsunami deposit was identified, and deposit migration analysis was conducted on the tsunami deposit distribution process of historical Nankai Trough earthquakes. Furthermore, examination of tsunami source conditions is possibly investigated by comparison studies of the observed data and the computation of tsunami deposit distribution. It is difficult to clarify details of tsunami source from indistinct information of paleogeographical conditions. However, this result shows that it can be used as a constraint condition of the tsunami source scale by combining tsunami deposit distribution in lakes with computation data.

  17. Long-term perspectives on giant earthquakes and tsunamis at subduction zones

    Science.gov (United States)

    Satake, K.; Atwater, B.F.; ,

    2007-01-01

    Histories of earthquakes and tsunamis, inferred from geological evidence, aid in anticipating future catastrophes. This natural warning system now influences building codes and tsunami planning in the United States, Canada, and Japan, particularly where geology demonstrates the past occurrence of earthquakes and tsunamis larger than those known from written and instrumental records. Under favorable circumstances, paleoseismology can thus provide long-term advisories of unusually large tsunamis. The extraordinary Indian Ocean tsunami of 2004 resulted from a fault rupture more than 1000 km in length that included and dwarfed fault patches that had broken historically during lesser shocks. Such variation in rupture mode, known from written history at a few subduction zones, is also characteristic of earthquake histories inferred from geology on the Pacific Rim. Copyright ?? 2007 by Annual Reviews. All rights reserved.

  18. A global probabilistic tsunami hazard assessment from earthquake sources

    Science.gov (United States)

    Davies, Gareth; Griffin, Jonathan; Lovholt, Finn; Glimsdal, Sylfest; Harbitz, Carl; Thio, Hong Kie; Lorito, Stefano; Basili, Roberto; Selva, Jacopo; Geist, Eric L.; Baptista, Maria Ana

    2017-01-01

    Large tsunamis occur infrequently but have the capacity to cause enormous numbers of casualties, damage to the built environment and critical infrastructure, and economic losses. A sound understanding of tsunami hazard is required to underpin management of these risks, and while tsunami hazard assessments are typically conducted at regional or local scales, globally consistent assessments are required to support international disaster risk reduction efforts, and can serve as a reference for local and regional studies. This study presents a global-scale probabilistic tsunami hazard assessment (PTHA), extending previous global-scale assessments based largely on scenario analysis. Only earthquake sources are considered, as they represent about 80% of the recorded damaging tsunami events. Globally extensive estimates of tsunami run-up height are derived at various exceedance rates, and the associated uncertainties are quantified. Epistemic uncertainties in the exceedance rates of large earthquakes often lead to large uncertainties in tsunami run-up. Deviations between modelled tsunami run-up and event observations are quantified, and found to be larger than suggested in previous studies. Accounting for these deviations in PTHA is important, as it leads to a pronounced increase in predicted tsunami run-up for a given exceedance rate.

  19. Extraction of two tsunamis signals generated by earthquakes around the Pacific rim

    Directory of Open Access Journals (Sweden)

    Chu Yonghai

    2014-05-01

    Full Text Available As one of the ocean sudden natural disasters, the tsunami is not easily to differentiate from the ocean variation in the open ocean due to the tsunami wave amplitude is lees than one meter with hundreds of kilometers wavelength. But the wave height will increases up to tens of meters with enormous energy when the tsunami aarives at the coast. It would not only devastate entire cities near coast, but also kill miilions of people. It is necessary to forecast and make warning before the tsunami aariving for many countries and regions around the Pacific rim. Two kinds of data were used in this study to extract the signals of 2011 Tohoku tsunami and 2014 Iquique tsunami. Wave undulations from DART (Deep-ocean Assessment and Reporting of Tsunamis buoys and SLA from altimetry could extract the tsunami signals generated by this two earthquake. The signals of Tohoku tsunami were stronger than that of Iquique tsunami probably due to the 2011 Tohoku tsunami was generated by a magnitude 9. 0 earthquake and the 2014 Iquique tsunami was triggered by a magnitude 8. 2 earthquake.

  20. Report by the 'Mega-earthquakes and mega-tsunamis' subgroup

    International Nuclear Information System (INIS)

    Friedel, Jacques; Courtillot, Vincent; Dercourt, Jean; Jaupart, Claude; Le Pichon, Xavier; Poirier, Jean-Paul; Salencon, Jean; Tapponnier, Paul; Dautray, Robert; Carpentier, Alain; Taquet, Philippe; Blanchet, Rene; Le Mouel, Jean-Louis; BARD, Pierre-Yves; Bernard, Pascal; Montagner, Jean-Paul; Armijo, Rolando; Shapiro, Nikolai; Tait, Steve; Cara, Michel; Madariaga, Raul; Pecker, Alain; Schindele, Francois; Douglas, John

    2011-06-01

    This report comprises a presentation of scientific data on subduction earthquakes, on tsunamis and on the Tohoku earthquake. It proposes a detailed description of the French situation (in the West Indies, in metropolitan France, and in terms of soil response), and a discussion of social and economic issues (governance, seismic regulation and nuclear safety, para-seismic protection of constructions). The report is completed by other large documents: presentation of data on the Japanese earthquake, discussion on prediction and governance errors in the management of earthquake mitigation in Japan, discussions on tsunami prevention, on needs of research on accelerometers, and on the seismic risk in France

  1. Tsunami Numerical Simulation for Hypothetical Giant or Great Earthquakes along the Izu-Bonin Trench

    Science.gov (United States)

    Harada, T.; Ishibashi, K.; Satake, K.

    2013-12-01

    We performed tsunami numerical simulations from various giant/great fault models along the Izu-Bonin trench in order to see the behavior of tsunamis originated in this region and to examine the recurrence pattern of great interplate earthquakes along the Nankai trough off southwest Japan. As a result, large tsunami heights are expected in the Ryukyu Islands and on the Pacific coasts of Kyushu, Shikoku and western Honshu. The computed large tsunami heights support the hypothesis that the 1605 Keicho Nankai earthquake was not a tsunami earthquake along the Nankai trough but a giant or great earthquake along the Izu-Bonin trench (Ishibashi and Harada, 2013, SSJ Fall Meeting abstract). The Izu-Bonin subduction zone has been regarded as so-called 'Mariana-type subduction zone' where M>7 interplate earthquakes do not occur inherently. However, since several M>7 outer-rise earthquakes have occurred in this region and the largest slip of the 2011 Tohoku earthquake (M9.0) took place on the shallow plate interface where the strain accumulation had considered to be a little, a possibility of M>8.5 earthquakes in this region may not be negligible. The latest M 7.4 outer-rise earthquake off the Bonin Islands on Dec. 22, 2010 produced small tsunamis on the Pacific coast of Japan except for the Tohoku and Hokkaido districts and a zone of abnormal seismic intensity in the Kanto and Tohoku districts. Ishibashi and Harada (2013) proposed a working hypothesis that the 1605 Keicho earthquake which is considered a great tsunami earthquake along the Nankai trough was a giant/great earthquake along the Izu-Bonin trench based on the similarity of the distributions of ground shaking and tsunami of this event and the 2010 Bonin earthquake. In this study, in order to examine the behavior of tsunamis from giant/great earthquakes along the Izu-Bonin trench and check the Ishibashi and Harada's hypothesis, we performed tsunami numerical simulations from fault models along the Izu-Bonin trench

  2. Earthquake and Tsunami: a movie and a book for seismic and tsunami risk reduction in Italy.

    Science.gov (United States)

    Nostro, C.; Baroux, E.; Maramai, A.; Graziani, L.; Tertulliani, A.; Castellano, C.; Arcoraci, L.; Casale, P.; Ciaccio, M. G.; Frepoli, A.

    2009-04-01

    Italy is a country well known for the seismic and volcanic hazard. However, a similarly great hazard, although not well recognized, is posed by the occurrence of tsunami waves along the Italian coastline. This is testified by a rich catalogue and by field evidence of deposits left over by pre- and historical tsunamis, even in places today considered safe. This observation is of great importance since many of the areas affected by tsunamis in the past are today touristic places. The Italian tsunamis can be caused by different sources: 1- off-shore or near coast in-land earthquakes; 2- very large earthquakes on distant sources in the Mediterranean; 3- submarine volcanic explosion in the Tyrrhenian sea; 4- submarine landslides triggered by earthquakes and volcanic activity. The consequence of such a wide spectrum of sources is that an important part of the more than 7000 km long Italian coast line is exposed to the tsunami risk, and thousands of inhabitants (with numbers increasing during summer) live near hazardous coasts. The main historical tsunamis are the 1783 and 1908 events that hit Calabrian and Sicilian coasts. The recent tsunami is that caused by the 2002 Stromboli landslide. In order to reduce this risk and following the emotional impact of the December 2004 Sumatra earthquake and tsunami, we developed an outreach program consisting in talks given by scientists and in a movie and a book, both exploring the causes of the tsunami waves, how do they propagate in deep and shallow waters, and what are the effects on the coasts. Hints are also given on the most dangerous Italian coasts (as deduced by scientific studies), and how to behave in the case of a tsunami approaching the coast. These seminars are open to the general public, but special programs are developed with schools of all grades. In this talk we want to present the book and the movie used during the seminars and scientific expositions, that was realized from a previous 3D version originally

  3. Tsunami simulation of 2011 Tohoku-Oki Earthquake. Evaluation of difference in tsunami wave pressure acting around Fukushima Daiichi Nuclear Power Station and Fukushima Daini Nuclear Power Station among different tsunami source models

    International Nuclear Information System (INIS)

    Fujihara, Satoru; Hashimoto, Norihiko; Korenaga, Mariko; Tamiya, Takahiro

    2016-01-01

    Since the 2011 Tohoku-Oki Earthquake, evaluations based on a tsunami simulation approach have had a very important role in promoting tsunami disaster prevention measures in the case of mega-thrust earthquakes. When considering tsunami disaster prevention measures based on the knowledge obtained from tsunami simulations, it is important to carefully examine the type of tsunami source model. In current tsunami simulations, there are various ways to set the tsunami source model, and a considerable difference in tsunami behavior can be expected among the tsunami source models. In this study, we carry out a tsunami simulation of the 2011 Tohoku-Oki Earthquake around Fukushima Daiichi (I) Nuclear Power Plant and Fukushima Daini (II) Nuclear Power Plant in Fukushima Prefecture, Japan, using several tsunami source models, and evaluate the difference in the tsunami behavior in the tsunami inundation process. The results show that for an incoming tsunami inundating an inland region, there are considerable relative differences in the maximum tsunami height and wave pressure. This suggests that there could be false information used in promoting tsunami disaster prevention measures in the case of mega-thrust earthquakes, depending on the tsunami source model. (author)

  4. New constraints on the magnitude of the 4 January 1907 tsunami earthquake off Sumatra, Indonesia, and its Indian Ocean-wide tsunami

    Science.gov (United States)

    Martin, S. S.; Li, L.; Okal, E.; Kanamori, H.; Morin, J.; Sieh, K.; Switzer, A.

    2017-12-01

    On 4 January 1907, an earthquake and tsunami occurred off the west coast of Sumatra, Indonesia, causing at least 2,188 fatalities. The earthquake was given an instrumental surface-wave magnitude (MS) in the range of 7.5 to 8.0 at periods of ≈40s. The tsunami it triggered was destructive on the islands of Nias and Simeulue; on the latter, this gave rise to the legend of the S'mong. This tsunami appears in records in India, Pakistan, Sri Lanka, and as far as the island of La Réunion. In relation to published seismic magnitudes for the earthquake, the tsunami was anomalously large, qualifying it as a "tsunami earthquake." Relocations using reported arrival times suggest an epicentral location near the trench. However, unusually for a tsunami earthquake the reported macroseismic intensities were higher than expected on Nias (6-7 EMS). We present a new study of this event based on macroseismic and tsunami observations culled from published literature and colonial press reports, as well as existing and newly acquired digitized or print seismograms. This multidisciplinary combination of macroseismic and seismological data with tsunami modelling has yielded new insights into this poorly understood but scientifically and societally important tsunami earthquake in the Indian Ocean. With these new data, we discriminated two large earthquakes within an hour of each other with clear differences in seismological character. The first, we interpret to be a tsunami earthquake with low levels of shaking (3-4 EMS). For this event, we estimate a seismic moment (M0) between 0.8 and 1.2 x1021 Nm (≈MW 7.9 to 8.0) based on digitized Wiechert records at Göttingen in the frequency band 6-8 mHz. These records document a regular growth of moment with period and suggest possibly larger values of M0 at even longer periods. The second earthquake caused damage on Nias (6-7 EMS). We estimate MS 6 ¾ - 7 for the second event based on seismograms from Manila, Mizusawa, and Osaka. We also

  5. Coral reefs as buffers during the 2009 South Pacific tsunami, Upolu Island, Samoa

    Science.gov (United States)

    McAdoo, Brian G.; Ah-Leong, Joyce Samuelu; Bell, Lui; Ifopo, Pulea; Ward, Juney; Lovell, Edward; Skelton, Posa

    2011-07-01

    The coral reef bordering the coastline of Samoa affected by the 29 September 2009 tsunami provides a variety of ecosystem services — from nurseries for fisheries and inshore source of food for local communities, to aesthetics for tourists, and the width of the lagoon may have been a factor in reducing the onshore wave height. To understand the complex interactions between the onshore human population and the offshore coral, we formed an interdisciplinary survey team to document the effects the tsunami had on the nearshore coral reef, and how these changes might affect local inhabitants. The scale of reef damage varied from severe, where piles of freshly-killed coral fragments and mortality were present, to areas that exhibited little impact, despite being overrun by the tsunami. We found that many coral colonies were impacted by tsunami-entrained coral debris, which had been ripped up and deposited on the fore reef by repeated cyclones and storm waves. In other places, large surface area tabular coral sustained damage as the tsunami velocity increased as it was funneled through channels. Areas that lacked debris entrained by the waves as well as areas in the lee of islands came through relatively unscathed, with the exception of the delicate corals that lived on a sandy substrate. In the lagoon on the south coast with its steep topography, coral colonies were damaged by tsunami-generated debris from onshore entrained in the backwash. Despite the potential for severe tsunami-related damage, there were no noticeable decreases in live coral cover between successive surveys at two locations, although algal cover was higher with the increased nutrients mobilized by the tsunami. While there was an immediate decrease in fish takes in the month following the tsunami, when supporting services were likely impacted, both volume and income have rapidly increased to pre-tsunami levels. Long-term monitoring should be implemented to determine if nursery services were affected.

  6. Study on tsunami due to offshore earthquakes for Korea coast. Literature survey and numerical simulation on earthquake and tsunami in the Japan Sea and the East China Sea

    International Nuclear Information System (INIS)

    Matsuyama, Masafumi; Aoyagi, Yasuhira; Inoue, Daiei; Choi, Weon-Hack; Kang, Keum-Seok

    2008-01-01

    In Korea, there has been a concern on tsumami risks for the Nuclear Power Plants since the 1983 Nihonkai-Chubu earthquake tsunami. The maximum run-up height reached 4 m to north of the Ulchin nuclear power plant site. The east coast of Korea was also attacked by a few meters high tsunami generated by the 1993 Hokkaido Nansei-Oki earthquake. Both source areas of them were in the areas western off Hokkaido to the eastern margin of the Japan Sea, which remains another tsunami potential. Therefore it is necessary to study tsunami risks for coast of Korea by means of geological investigation and numerical simulation. Historical records of earthquake and tsunami in the Japan Sea were re-compiled to evaluate tsunami potential. A database of marine active faults in the Japan Sea was compiled to decide a regional potential of tsunami. Many developed reverse faults are found in the areas western off Hokkaido to the eastern margin of the Japan Sea. The authors have found no historical earthquake in the East China Sea which caused tunami observed at coast of Korea. Therefore five fault models were determined on the basis of the analysis results of historical records and recent research results of fault parameter and tunami. Tsunami heights were estimated by numerical simulation of nonlinear dispersion wave theory. The results of the simulations indicate that the tsunami heights in these cases are less than 0.25 m along the coast of Korea, and the tsunami risk by these assumed faults does not lead to severe impact. It is concluded that tsunami occurred in the areas western off Hokkaido to the eastern margin of the Japan Sea leads the most significant impact to Korea consequently. (author)

  7. FEATURES AND PROBLEMS WITH HISTORICAL GREAT EARTHQUAKES AND TSUNAMIS IN THE MEDITERRANEAN SEA

    Directory of Open Access Journals (Sweden)

    Lobkovsky L.

    2016-11-01

    Full Text Available The present study examines the historical earthquakes and tsunamis of 21 July 365 and of 9 February 1948 in the Eastern Mediterranean Sea. Numerical simulations were performed for the tsunamis generated by underwater seismic sources in frames of the keyboard model, as well as for their propagation in the Mediterranean Sea basin. Similarly examined were three different types of seismic sources at the same localization near the Island of Crete for the earthquake of 21 July 365, and of two different types of seismic sources for the earthquake of 9 February 1948 near the Island of Karpathos. For each scenario, the tsunami wave field characteristics from the earthquake source to coastal zones in Mediterranean Sea’s basin were obtained and histograms were constructed showing the distribution of maximum tsunami wave heights, along a 5-m isobath. Comparison of tsunami wave characteristics for all the above mentioned scenarios, demonstrates that underwater earthquakes with magnitude M > 7 in the Eastern Mediterranean Sea basin, can generate waves with coastal runup up to 9 m.

  8. Aftereffects of Subduction-Zone Earthquakes: Potential Tsunami Hazards along the Japan Sea Coast.

    Science.gov (United States)

    Minoura, Koji; Sugawara, Daisuke; Yamanoi, Tohru; Yamada, Tsutomu

    2015-10-01

    The 2011 Tohoku-Oki Earthquake is a typical subduction-zone earthquake and is the 4th largest earthquake after the beginning of instrumental observation of earthquakes in the 19th century. In fact, the 2011 Tohoku-Oki Earthquake displaced the northeast Japan island arc horizontally and vertically. The displacement largely changed the tectonic situation of the arc from compressive to tensile. The 9th century in Japan was a period of natural hazards caused by frequent large-scale earthquakes. The aseismic tsunamis that inflicted damage on the Japan Sea coast in the 11th century were related to the occurrence of massive earthquakes that represented the final stage of a period of high seismic activity. Anti-compressive tectonics triggered by the subduction-zone earthquakes induced gravitational instability, which resulted in the generation of tsunamis caused by slope failing at the arc-back-arc boundary. The crustal displacement after the 2011 earthquake infers an increased risk of unexpected local tsunami flooding in the Japan Sea coastal areas.

  9. Coastal evidence for Holocene subduction-zone earthquakes and tsunamis in central Chile

    Science.gov (United States)

    Dure, Tina; Cisternas, Marco; Horton, Benjamin; Ely, Lisa; Nelson, Alan R.; Wesson, Robert L.; Pilarczyk, Jessica

    2015-01-01

    The ∼500-year historical record of seismicity along the central Chile coast (30–34°S) is characterized by a series of ∼M 8.0–8.5 earthquakes followed by low tsunamis (tsunami (>10 m), but the frequency of such large events is unknown. We extend the seismic history of central Chile through a study of a lowland stratigraphic sequence along the metropolitan coast north of Valparaíso (33°S). At this site, higher relative sea level during the mid Holocene created a tidal marsh and the accommodation space necessary for sediment that preserves earthquake and tsunami evidence. Within this 2600-yr-long sequence, we traced six laterally continuous sand beds probably deposited by high tsunamis. Plant remains that underlie the sand beds were radiocarbon dated to 6200, 5600, 5000, 4400, 3800, and 3700 cal yr BP. Sediment properties and diatom assemblages of the sand beds—for example, anomalous marine planktonic diatoms and upward fining of silt-sized diatom valves—point to a marine sediment source and high-energy deposition. Grain-size analysis shows a strong similarity between inferred tsunami deposits and modern coastal sediment. Upward fining sequences characteristic of suspension deposition are present in five of the six sand beds. Despite the lack of significant lithologic changes between the sedimentary units under- and overlying tsunami deposits, we infer that the increase in freshwater siliceous microfossils in overlying units records coseismic uplift concurrent with the deposition of five of the sand beds. During our mid-Holocene window of evidence preservation, the mean recurrence interval of earthquakes and tsunamis is ∼500 years. Our findings imply that the frequency of historical earthquakes in central Chile is not representative of the greatest earthquakes and tsunamis that the central Chilean subduction zone has produced.

  10. New Geological Evidence of Past Earthquakes and Tsunami Along the Nankai Trough, Japan

    Science.gov (United States)

    De Batist, M. A. O.; Heyvaert, V.; Hubert-Ferrari, A.; Fujiwara, O.; Shishikura, M.; Yokoyama, Y.; Brückner, H.; Garrett, E.; Boes, E.; Lamair, L.; Nakamura, A.; Miyairi, Y.; Yamamoto, S.

    2015-12-01

    The east coast of Japan is prone to tsunamigenic megathrust earthquakes, as tragically demonstrated in 2011 by the Tōhoku earthquake (Mw 9.0) and tsunami. The Nankai Trough subduction zone, to the southwest of the area affected by the Tōhoku disaster and facing the densely populated and heavily industrialized southern coastline of central and west Japan, is expected to generate another megathrust earthquake and tsunami in the near future. This subduction zone is, however, segmented and appears to be characterized by a variable rupture mode, involving single- as well as multi-segment ruptures, which has immediate implications for their tsunamigenic potential, and also renders the collection of sufficiently long time records of past earthquakes and tsunami in this region fundamental for an adequate hazard and risk assessment. Over the past three decades, Japanese researchers have acquired a large amount of geological evidence of past earthquakes and tsunami, in many cases extending back in time for several thousands of years. This evidence includes uplifted marine terraces, turbidites, liquefaction features, subsided marshes and tsunami deposits in coastal lakes and lowlands. Despite these efforts, current understanding of the behaviour of the subduction zone still remains limited, due to site-specific evidence creation and preservation thresholds and issues over alternative hypotheses for proposed palaeoseismic evidence and insufficiently precise chronological control. Within the QuakeRecNankai project we are generating a long and coherent time series of megathrust earthquake and tsunami recurrences along the Nankai Trough subduction zone by integrating all existing evidence with new geological records of paleo-tsunami in the Lake Hamana region and of paleo-earthquakes from selected lakes in the Mount Fuji area. We combine extensive fieldwork in coastal plain areas and lakes, with advanced sedimentological and geochemical analyses and innovative dating techniques.

  11. The 1997 Kronotsky earthquake and tsunami and their predecessors, Kamchatka, Russia

    Science.gov (United States)

    Bourgeois, Joanne; Pinegina, Tatiana K.

    2018-01-01

    The northern part of the Kamchatka subduction zone (KSZ) experienced three tsunamigenic earthquakes in the 20th century - February 1923, April 1923, December 1997 - events that help us better understand the behavior of this segment. A particular focus of this study is the nature and location of the 5 December 1997 Kronotsky rupture (Mw ˜ 7.8) as elucidated by tsunami runup north of Kronotsky Peninsula in southern to central Kamchatsky Bay. Some studies have characterized the subduction zone off Kronotsky Peninsula as either more locked or more smoothly slipping than surrounding areas and have placed the 1997 rupture south of this promontory. However, 1997 tsunami runup north of the peninsula, as evidenced by our mapping of tsunami deposits, requires the rupture to extend farther north. Previously reported runup (1997 tsunami) on Kronotsky Peninsula was no more than 2-3 m, but our studies indicate tsunami heights for at least 50 km north of Kronotsky Peninsula in Kamchatsky Bay, ranging from 3.4 to 9.5 m (average 6.1 m), exceeding beach ridge heights of 5.3 to 8.3 m (average 7.1 m). For the two 1923 tsunamis, we cannot distinguish among their deposits in southern to central Kamchatsky Bay, but the deposits are more extensive than the 1997 deposit. A reevaluation of the April 1923 historical tsunami suggests that its moment magnitude could be revised upward, and that the 1997 earthquake filled a gap between the two 1923 earthquake ruptures. Characterizing these historical earthquakes and tsunamis in turn contributes to interpreting the prehistoric record, which is necessary to evaluate recurrence intervals for such events. Deeper in time, the prehistoric record back to ˜ AD 300 in southern to central Kamchatsky Bay indicates that during this interval, there were no local events significantly larger than those of the 20th century. Together, the historic and prehistoric tsunami record suggests a more northerly location of the 1997 rupture compared to most other

  12. The 1997 Kronotsky earthquake and tsunami and their predecessors, Kamchatka, Russia

    Directory of Open Access Journals (Sweden)

    J. Bourgeois

    2018-01-01

    Full Text Available The northern part of the Kamchatka subduction zone (KSZ experienced three tsunamigenic earthquakes in the 20th century – February 1923, April 1923, December 1997 – events that help us better understand the behavior of this segment. A particular focus of this study is the nature and location of the 5 December 1997 Kronotsky rupture (Mw ∼ 7.8 as elucidated by tsunami runup north of Kronotsky Peninsula in southern to central Kamchatsky Bay. Some studies have characterized the subduction zone off Kronotsky Peninsula as either more locked or more smoothly slipping than surrounding areas and have placed the 1997 rupture south of this promontory. However, 1997 tsunami runup north of the peninsula, as evidenced by our mapping of tsunami deposits, requires the rupture to extend farther north. Previously reported runup (1997 tsunami on Kronotsky Peninsula was no more than 2–3 m, but our studies indicate tsunami heights for at least 50 km north of Kronotsky Peninsula in Kamchatsky Bay, ranging from 3.4 to 9.5 m (average 6.1 m, exceeding beach ridge heights of 5.3 to 8.3 m (average 7.1 m. For the two 1923 tsunamis, we cannot distinguish among their deposits in southern to central Kamchatsky Bay, but the deposits are more extensive than the 1997 deposit. A reevaluation of the April 1923 historical tsunami suggests that its moment magnitude could be revised upward, and that the 1997 earthquake filled a gap between the two 1923 earthquake ruptures. Characterizing these historical earthquakes and tsunamis in turn contributes to interpreting the prehistoric record, which is necessary to evaluate recurrence intervals for such events. Deeper in time, the prehistoric record back to ∼ AD 300 in southern to central Kamchatsky Bay indicates that during this interval, there were no local events significantly larger than those of the 20th century. Together, the historic and prehistoric tsunami record suggests a more northerly location of

  13. Web-based Tsunami Early Warning System: a case study of the 2010 Kepulaunan Mentawai Earthquake and Tsunami

    Directory of Open Access Journals (Sweden)

    E. Ulutas

    2012-06-01

    Full Text Available This study analyzes the response of the Global Disasters Alerts and Coordination System (GDACS in relation to a case study: the Kepulaunan Mentawai earthquake and related tsunami, which occurred on 25 October 2010. The GDACS, developed by the European Commission Joint Research Center, combines existing web-based disaster information management systems with the aim to alert the international community in case of major disasters. The tsunami simulation system is an integral part of the GDACS. In more detail, the study aims to assess the tsunami hazard on the Mentawai and Sumatra coasts: the tsunami heights and arrival times have been estimated employing three propagation models based on the long wave theory. The analysis was performed in three stages: (1 pre-calculated simulations by using the tsunami scenario database for that region, used by the GDACS system to estimate the alert level; (2 near-real-time simulated tsunami forecasts, automatically performed by the GDACS system whenever a new earthquake is detected by the seismological data providers; and (3 post-event tsunami calculations using GCMT (Global Centroid Moment Tensor fault mechanism solutions proposed by US Geological Survey (USGS for this event. The GDACS system estimates the alert level based on the first type of calculations and on that basis sends alert messages to its users; the second type of calculations is available within 30–40 min after the notification of the event but does not change the estimated alert level. The third type of calculations is performed to improve the initial estimations and to have a better understanding of the extent of the possible damage. The automatic alert level for the earthquake was given between Green and Orange Alert, which, in the logic of GDACS, means no need or moderate need of international humanitarian assistance; however, the earthquake generated 3 to 9 m tsunami run-up along southwestern coasts of the Pagai Islands where 431 people died

  14. Safety analysis of nuclear containment vessels subjected to strong earthquakes and subsequent tsunamis

    Energy Technology Data Exchange (ETDEWEB)

    Lin, Feng; Li, Hong Zhi [Dept. Structural Engineering, Tongji University, Shanghai (China)

    2017-08-15

    Nuclear power plants under expansion and under construction in China are mostly located in coastal areas, which means they are at risk of suffering strong earthquakes and subsequent tsunamis. This paper presents a safety analysis for a new reinforced concrete containment vessel in such events. A finite element method-based model was built, verified, and first used to understand the seismic performance of the containment vessel under earthquakes with increased intensities. Then, the model was used to assess the safety performance of the containment vessel subject to an earthquake with peak ground acceleration (PGA) of 0.56g and subsequent tsunamis with increased inundation depths, similar to the 2011 Great East earthquake and tsunami in Japan. Results indicated that the containment vessel reached Limit State I (concrete cracking) and Limit State II (concrete crushing) when the PGAs were in a range of 0.8–1.1g and 1.2–1.7g, respectively. The containment vessel reached Limit State I with a tsunami inundation depth of 10 m after suffering an earthquake with a PGA of 0.56g. A site-specific hazard assessment was conducted to consider the likelihood of tsunami sources.

  15. Concerns over modeling and warning capabilities in wake of Tohoku Earthquake and Tsunami

    Science.gov (United States)

    Showstack, Randy

    2011-04-01

    Improved earthquake models, better tsunami modeling and warning capabilities, and a review of nuclear power plant safety are all greatly needed following the 11 March Tohoku earthquake and tsunami, according to scientists at the European Geosciences Union's (EGU) General Assembly, held 3-8 April in Vienna, Austria. EGU quickly organized a morning session of oral presentations and an afternoon panel discussion less than 1 month after the earthquake and the tsunami and the resulting crisis at Japan's Fukushima nuclear power plant, which has now been identified as having reached the same level of severity as the 1986 Chernobyl disaster. Many of the scientists at the EGU sessions expressed concern about the inability to have anticipated the size of the earthquake and the resulting tsunami, which appears likely to have caused most of the fatalities and damage, including damage to the nuclear plant.

  16. Introduction to "Global Tsunami Science: Past and Future, Volume III"

    Science.gov (United States)

    Rabinovich, Alexander B.; Fritz, Hermann M.; Tanioka, Yuichiro; Geist, Eric L.

    2018-04-01

    Twenty papers on the study of tsunamis are included in Volume III of the PAGEOPH topical issue "Global Tsunami Science: Past and Future". Volume I of this topical issue was published as PAGEOPH, vol. 173, No. 12, 2016 and Volume II as PAGEOPH, vol. 174, No. 8, 2017. Two papers in Volume III focus on specific details of the 2009 Samoa and the 1923 northern Kamchatka tsunamis; they are followed by three papers related to tsunami hazard assessment for three different regions of the world oceans: South Africa, Pacific coast of Mexico and the northwestern part of the Indian Ocean. The next six papers are on various aspects of tsunami hydrodynamics and numerical modelling, including tsunami edge waves, resonant behaviour of compressible water layer during tsunamigenic earthquakes, dispersive properties of seismic and volcanically generated tsunami waves, tsunami runup on a vertical wall and influence of earthquake rupture velocity on maximum tsunami runup. Four papers discuss problems of tsunami warning and real-time forecasting for Central America, the Mediterranean coast of France, the coast of Peru, and some general problems regarding the optimum use of the DART buoy network for effective real-time tsunami warning in the Pacific Ocean. Two papers describe historical and paleotsunami studies in the Russian Far East. The final set of three papers importantly investigates tsunamis generated by non-seismic sources: asteroid airburst and meteorological disturbances. Collectively, this volume highlights contemporary trends in global tsunami research, both fundamental and applied toward hazard assessment and mitigation.

  17. NEAR REAL-TIME DETERMINATION OF EARTHQUAKE SOURCE PARAMETERS FOR TSUNAMI EARLY WARNING FROM GEODETIC OBSERVATIONS

    Directory of Open Access Journals (Sweden)

    S. Manneela

    2016-06-01

    Full Text Available Exemplifying the tsunami source immediately after an earthquake is the most critical component of tsunami early warning, as not every earthquake generates a tsunami. After a major under sea earthquake, it is very important to determine whether or not it has actually triggered the deadly wave. The near real-time observations from near field networks such as strong motion and Global Positioning System (GPS allows rapid determination of fault geometry. Here we present a complete processing chain of Indian Tsunami Early Warning System (ITEWS, starting from acquisition of geodetic raw data, processing, inversion and simulating the situation as it would be at warning center during any major earthquake. We determine the earthquake moment magnitude and generate the centroid moment tensor solution using a novel approach which are the key elements for tsunami early warning. Though the well established seismic monitoring network, numerical modeling and dissemination system are currently capable to provide tsunami warnings to most of the countries in and around the Indian Ocean, the study highlights the critical role of geodetic observations in determination of tsunami source for high-quality forecasting.

  18. The "Tsunami Earthquake" of 13 April 1923 in Northern Kamchatka: Seismological and Hydrodynamic Investigations

    Science.gov (United States)

    Salaree, Amir; Okal, Emile A.

    2018-04-01

    We present a seismological and hydrodynamic investigation of the earthquake of 13 April 1923 at Ust'-Kamchatsk, Northern Kamchatka, which generated a more powerful and damaging tsunami than the larger event of 03 February 1923, thus qualifying as a so-called "tsunami earthquake". On the basis of modern relocations, we suggest that it took place outside the fault area of the mainshock, across the oblique Pacific-North America plate boundary, a model confirmed by a limited dataset of mantle waves, which also confirms the slow nature of the source, characteristic of tsunami earthquakes. However, numerical simulations for a number of legitimate seismic models fail to reproduce the sharply peaked distribution of tsunami wave amplitudes reported in the literature. By contrast, we can reproduce the distribution of reported wave amplitudes using an underwater landslide as a source of the tsunami, itself triggered by the earthquake inside the Kamchatskiy Bight.

  19. Alaska earthquake source for the SAFRR tsunami scenario: Chapter B in The SAFRR (Science Application for Risk Reduction) Tsunami Scenario

    Science.gov (United States)

    Kirby, Stephen; Scholl, David; von Huene, Roland E.; Wells, Ray

    2013-01-01

    Tsunami modeling has shown that tsunami sources located along the Alaska Peninsula segment of the Aleutian-Alaska subduction zone have the greatest impacts on southern California shorelines by raising the highest tsunami waves for a given source seismic moment. The most probable sector for a Mw ~ 9 source within this subduction segment is between Kodiak Island and the Shumagin Islands in what we call the Semidi subduction sector; these bounds represent the southwestern limit of the 1964 Mw 9.2 Alaska earthquake rupture and the northeastern edge of the Shumagin sector that recent Global Positioning System (GPS) observations indicate is currently creeping. Geological and geophysical features in the Semidi sector that are thought to be relevant to the potential for large magnitude, long-rupture-runout interplate thrust earthquakes are remarkably similar to those in northeastern Japan, where the destructive Mw 9.1 tsunamigenic earthquake of 11 March 2011 occurred. In this report we propose and justify the selection of a tsunami source seaward of the Alaska Peninsula for use in the Tsunami Scenario that is part of the U.S. Geological Survey (USGS) Science Application for Risk Reduction (SAFRR) Project. This tsunami source should have the potential to raise damaging tsunami waves on the California coast, especially at the ports of Los Angeles and Long Beach. Accordingly, we have summarized and abstracted slip distribution from the source literature on the 2011 event, the best characterized for any subduction earthquake, and applied this synoptic slip distribution to the similar megathrust geometry of the Semidi sector. The resulting slip model has an average slip of 18.6 m and a moment magnitude of Mw = 9.1. The 2011 Tohoku earthquake was not anticipated, despite Japan having the best seismic and geodetic networks in the world and the best historical record in the world over the past 1,500 years. What was lacking was adequate paleogeologic data on prehistoric earthquakes

  20. Pakistan’s Earthquake and Tsunami Hazards Potential Impact on Infrastructure

    Directory of Open Access Journals (Sweden)

    GEORGE PARARAS-CARAYANNIS

    2011-06-01

    Full Text Available Interaction of the Indian, Arabian and Eurasian tectonic plates has resulted in the formation of major active fault systems in South Asia. Compression along the tectonic boundaries results in thrust or reverse type of faulting and zones of crustal deformation characterized by high seismic activity and continuing Orogenesis. The more intense seismic activity occurs near regions of thrust faulting which is developing at the Himalayan foothills. In northern Pakistan, the Hindu Kush Mountains converge with the Karakoram Range to form a part of the Himalayan mountain system. Northern, western as well as southern Pakistan, Kashmir and northern India and Afghanistan are along such zones of high seismic activity. In Pakistan, most of the earthquakes occur in the north and western regions along the boundary of the Indian tectonic plate with the Iranian and Afghan micro-plates. The active zone extends from the Makran region in the southwest to the Hazara-Kashmir syntaxial bend in the north. Southwest Pakistan is vulnerable to both earthquake and tsunami hazards. In 2005, earthquakes devastated northern Pakistan and Kashmir and severely affected the cities of Muzaffarabad, Islamadad and Rawalpindi, causing severe destruction to the infrastructure of the northern region. A major earthquake along an extensive transform fault system in 1935 destroyed the city Quetta and the adjoining region. A major earthquake along the northern Arabian sea in 1945 generated a very destructive tsunami along the coasts of Baluchistan and Sindh Provinces. The region near Karachi is vulnerable as it is located near four major faults where destructive earthquakes and tsunamis have occurred in the past. Given Pakistan’s vulnerability and extensive infrastructure development in recent years, the present study reviews briefly the earthquake and tsunami risk factors and assesses the impact that such disasters can have on the country’s critical infrastructure - which includes

  1. Coastal evidence for Holocene subduction-zone earthquakes and tsunamis in central Chile

    Science.gov (United States)

    Dure, Tina; Cisternas, Marco; Horton, Benjamin; Ely, Lisa; Nelson, Alan R.; Wesson, Robert L.; Pilarczyk, Jessica

    2015-01-01

    The ∼500-year historical record of seismicity along the central Chile coast (30–34°S) is characterized by a series of ∼M 8.0–8.5 earthquakes followed by low tsunamis (10 m), but the frequency of such large events is unknown. We extend the seismic history of central Chile through a study of a lowland stratigraphic sequence along the metropolitan coast north of Valparaíso (33°S). At this site, higher relative sea level during the mid Holocene created a tidal marsh and the accommodation space necessary for sediment that preserves earthquake and tsunami evidence. Within this 2600-yr-long sequence, we traced six laterally continuous sand beds probably deposited by high tsunamis. Plant remains that underlie the sand beds were radiocarbon dated to 6200, 5600, 5000, 4400, 3800, and 3700 cal yr BP. Sediment properties and diatom assemblages of the sand beds—for example, anomalous marine planktonic diatoms and upward fining of silt-sized diatom valves—point to a marine sediment source and high-energy deposition. Grain-size analysis shows a strong similarity between inferred tsunami deposits and modern coastal sediment. Upward fining sequences characteristic of suspension deposition are present in five of the six sand beds. Despite the lack of significant lithologic changes between the sedimentary units under- and overlying tsunami deposits, we infer that the increase in freshwater siliceous microfossils in overlying units records coseismic uplift concurrent with the deposition of five of the sand beds. During our mid-Holocene window of evidence preservation, the mean recurrence interval of earthquakes and tsunamis is ∼500 years. Our findings imply that the frequency of historical earthquakes in central Chile is not representative of the greatest earthquakes and tsunamis that the central Chilean subduction zone has produced.

  2. The effect of compliant prisms on subduction zone earthquakes and tsunamis

    Science.gov (United States)

    Lotto, Gabriel C.; Dunham, Eric M.; Jeppson, Tamara N.; Tobin, Harold J.

    2017-01-01

    Earthquakes generate tsunamis by coseismically deforming the seafloor, and that deformation is largely controlled by the shallow rupture process. Therefore, in order to better understand how earthquakes generate tsunamis, one must consider the material structure and frictional properties of the shallowest part of the subduction zone, where ruptures often encounter compliant sedimentary prisms. Compliant prisms have been associated with enhanced shallow slip, seafloor deformation, and tsunami heights, particularly in the context of tsunami earthquakes. To rigorously quantify the role compliant prisms play in generating tsunamis, we perform a series of numerical simulations that directly couple dynamic rupture on a dipping thrust fault to the elastodynamic response of the Earth and the acoustic response of the ocean. Gravity is included in our simulations in the context of a linearized Eulerian description of the ocean, which allows us to model tsunami generation and propagation, including dispersion and related nonhydrostatic effects. Our simulations span a three-dimensional parameter space of prism size, prism compliance, and sub-prism friction - specifically, the rate-and-state parameter b - a that determines velocity-weakening or velocity-strengthening behavior. We find that compliant prisms generally slow rupture velocity and, for larger prisms, generate tsunamis more efficiently than subduction zones without prisms. In most but not all cases, larger, more compliant prisms cause greater amounts of shallow slip and larger tsunamis. Furthermore, shallow friction is also quite important in determining overall slip; increasing sub-prism b - a enhances slip everywhere along the fault. Counterintuitively, we find that in simulations with large prisms and velocity-strengthening friction at the base of the prism, increasing prism compliance reduces rather than enhances shallow slip and tsunami wave height.

  3. Safety analysis of nuclear containment vessels subjected to strong earthquakes and subsequent tsunamis

    Directory of Open Access Journals (Sweden)

    Feng Lin

    2017-08-01

    Full Text Available Nuclear power plants under expansion and under construction in China are mostly located in coastal areas, which means they are at risk of suffering strong earthquakes and subsequent tsunamis. This paper presents a safety analysis for a new reinforced concrete containment vessel in such events. A finite element method-based model was built, verified, and first used to understand the seismic performance of the containment vessel under earthquakes with increased intensities. Then, the model was used to assess the safety performance of the containment vessel subject to an earthquake with peak ground acceleration (PGA of 0.56g and subsequent tsunamis with increased inundation depths, similar to the 2011 Great East earthquake and tsunami in Japan. Results indicated that the containment vessel reached Limit State I (concrete cracking and Limit State II (concrete crushing when the PGAs were in a range of 0.8–1.1g and 1.2–1.7g, respectively. The containment vessel reached Limit State I with a tsunami inundation depth of 10 m after suffering an earthquake with a PGA of 0.56g. A site-specific hazard assessment was conducted to consider the likelihood of tsunami sources.

  4. Introduction to “Global tsunami science: Past and future, Volume III”

    Science.gov (United States)

    Rabinovich, Alexander B.; Fritz, Hermann M.; Tanioka, Yuichiro; Geist, Eric L.

    2018-01-01

    Twenty papers on the study of tsunamis are included in Volume III of the PAGEOPH topical issue “Global Tsunami Science: Past and Future”. Volume I of this topical issue was published as PAGEOPH, vol. 173, No. 12, 2016 and Volume II as PAGEOPH, vol. 174, No. 8, 2017. Two papers in Volume III focus on specific details of the 2009 Samoa and the 1923 northern Kamchatka tsunamis; they are followed by three papers related to tsunami hazard assessment for three different regions of the world oceans: South Africa, Pacific coast of Mexico and the northwestern part of the Indian Ocean. The next six papers are on various aspects of tsunami hydrodynamics and numerical modelling, including tsunami edge waves, resonant behaviour of compressible water layer during tsunamigenic earthquakes, dispersive properties of seismic and volcanically generated tsunami waves, tsunami runup on a vertical wall and influence of earthquake rupture velocity on maximum tsunami runup. Four papers discuss problems of tsunami warning and real-time forecasting for Central America, the Mediterranean coast of France, the coast of Peru, and some general problems regarding the optimum use of the DART buoy network for effective real-time tsunami warning in the Pacific Ocean. Two papers describe historical and paleotsunami studies in the Russian Far East. The final set of three papers importantly investigates tsunamis generated by non-seismic sources: asteroid airburst and meteorological disturbances. Collectively, this volume highlights contemporary trends in global tsunami research, both fundamental and applied toward hazard assessment and mitigation.

  5. Slip reactivation model for the 2011 Mw9 Tohoku earthquake: Dynamic rupture, sea floor displacements and tsunami simulations.

    Science.gov (United States)

    Galvez, P.; Dalguer, L. A.; Rahnema, K.; Bader, M.

    2014-12-01

    up-lift close to the trench, which may be the cause of such a devastating tsunami followed by the Tohoku earthquake. To investigate the impact of such a huge up-lift, we ran tsunami simulations with the slip reactivation model using sam(oa)2 (O. Meister et al., 2012), a state-of-the-art Finite-Volume framework to simulate the resulting tsunami waves.

  6. Seismic hazard of American Samoa and neighboring South Pacific Islands--methods, data, parameters, and results

    Science.gov (United States)

    Petersen, Mark D.; Harmsen, Stephen C.; Rukstales, Kenneth S.; Mueller, Charles S.; McNamara, Daniel E.; Luco, Nicolas; Walling, Melanie

    2012-01-01

    American Samoa and the neighboring islands of the South Pacific lie near active tectonic-plate boundaries that host many large earthquakes which can result in strong earthquake shaking and tsunamis. To mitigate earthquake risks from future ground shaking, the Federal Emergency Management Agency requested that the U.S. Geological Survey prepare seismic hazard maps that can be applied in building-design criteria. This Open-File Report describes the data, methods, and parameters used to calculate the seismic shaking hazard as well as the output hazard maps, curves, and deaggregation (disaggregation) information needed for building design. Spectral acceleration hazard for 1 Hertz having a 2-percent probability of exceedance on a firm rock site condition (Vs30=760 meters per second) is 0.12 acceleration of gravity (1 second, 1 Hertz) and 0.32 acceleration of gravity (0.2 seconds, 5 Hertz) on American Samoa, 0.72 acceleration of gravity (1 Hertz) and 2.54 acceleration of gravity (5 Hertz) on Tonga, 0.15 acceleration of gravity (1 Hertz) and 0.55 acceleration of gravity (5 Hertz) on Fiji, and 0.89 acceleration of gravity (1 Hertz) and 2.77 acceleration of gravity (5 Hertz) on the Vanuatu Islands.

  7. Signals in the ionosphere generated by tsunami earthquakes: observations and modeling suppor

    Science.gov (United States)

    Rolland, L.; Sladen, A.; Mikesell, D.; Larmat, C. S.; Rakoto, V.; Remillieux, M.; Lee, R.; Khelfi, K.; Lognonne, P. H.; Astafyeva, E.

    2017-12-01

    Forecasting systems failed to predict the magnitude of the 2011 great tsunami in Japan due to the difficulty and cost of instrumenting the ocean with high-quality and dense networks. Melgar et al. (2013) show that using all of the conventional data (inland seismic, geodetic, and tsunami gauges) with the best inversion method still fails to predict the correct height of the tsunami before it breaks onto a coast near the epicenter (Even though typical tsunami waves are only a few centimeters high, they are powerful enough to create atmospheric vibrations extending all the way to the ionosphere, 300 kilometers up in the atmosphere. Therefore, we are proposing to incorporate the ionospheric signals into tsunami early-warning systems. We anticipate that the method could be decisive for mitigating "tsunami earthquakes" which trigger tsunamis larger than expected from their short-period magnitude. These events are challenging to characterize as they rupture the near-trench subduction interface, in a distant region less constrained by onshore data. As a couple of devastating tsunami earthquakes happens per decade, they represent a real threat for onshore populations and a challenge for tsunami early-warning systems. We will present the TEC observations of the recent Java 2006 and Mentawaii 2010 tsunami earthquakes and base our analysis on acoustic ray tracing, normal modes summation and the simulation code SPECFEM, which solves the wave equation in coupled acoustic (ocean, atmosphere) and elastic (solid earth) domains. Rupture histories are entered as finite source models, which will allow us to evaluate the effect of a relatively slow rupture on the surrounding ocean and atmosphere.

  8. Scientists Examine Challenges and Lessons From Japan's Earthquake and Tsunami

    Science.gov (United States)

    Showstack, Randy

    2011-03-01

    A week after the magnitude 9.0 great Tohoku earthquake and the resulting tragic and damaging tsunami of 11 March struck Japan, the ramifications continued, with a series of major aftershocks (as Eos went to press, there had been about 4 dozen with magnitudes greater than 6); the grim search for missing people—the death toll was expected to approximate 10,000; the urgent assistance needed for the more than 400,000 homeless and the 1 million people without water; and the frantic efforts to avert an environmental catastrophe at Japan's damaged Fukushima Daiichi Nuclear Power Station, about 225 kilometers northeast of Tokyo, where radiation was leaking. The earthquake offshore of Honshu in northeastern Japan (see Figure 1) was a plate boundary rupture along the Japan Trench subduction zone, with the source area of the earthquake estimated at 400-500 kilometers long with a maximum slip of 20 meters, determined through various means including Global Positioning System (GPS) and seismographic data, according to Kenji Satake, professor at the Earthquake Research Institute of the University of Tokyo. In some places the tsunami may have topped 7 meters—the maximum instrumental measurement at many coastal tide gauges—and some parts of the coastline may have been inundated more than 5 kilometers inland, Satake indicated. The International Tsunami Information Center (ITIC) noted that eyewitnesses reported that the highest tsunami waves were 13 meters high. Satake also noted that continuous GPS stations indicate that the coast near Sendai—which is 130 kilometers west of the earthquake and is the largest city in the Tohoku region of Honshu—moved more than 4 meters horizontally and subsided about 0.8 meter.

  9. Towards an Earthquake and Tsunami Early Warning in the Caribbean

    Science.gov (United States)

    Huerfano Moreno, V. A.; Vanacore, E. A.

    2017-12-01

    The Caribbean region (CR) has a documented history of large damaging earthquakes and tsunamis that have affected coastal areas, including the events of Jamaica in 1692, Virgin Islands in 1867, Puerto Rico in 1918, the Dominican Republic in 1946 and Haiti in 2010. There is clear evidence that tsunamis have been triggered by large earthquakes that deformed the ocean floor around the Caribbean Plate boundary. The CR is monitored jointly by national/regional/local seismic, geodetic and sea level networks. All monitoring institutions are participating in the UNESCO ICG/Caribe EWS, the purpose of this initiative is to minimize loss of life and destruction of property, and to mitigate against catastrophic economic impacts via promoting local research, real time (RT) earthquake, geodetic and sea level data sharing and improving warning capabilities and enhancing education and outreach strategies. Currently more than, 100 broad-band seismic, 65 sea levels and 50 GPS high rate stations are available in real or near real-time. These real-time streams are used by Local/Regional or Worldwide detection and warning institutions to provide earthquake source parameters in a timely manner. Currently, any Caribbean event detected to have a magnitude greater than 4.5 is evaluated, and sea level is measured, by the TWC for tsumanigenic potential. The regional cooperation is motivated both by research interests as well as geodetic, seismic and tsunami hazard monitoring and warning. It will allow the imaging of the tectonic structure of the Caribbean region to a high resolution which will consequently permit further understanding of the seismic source properties for moderate and large events and the application of this knowledge to procedures of civil protection. To reach its goals, the virtual network has been designed following the highest technical standards: BB sensors, 24 bits A/D converters with 140 dB dynamic range, real-time telemetry. Here we will discuss the state of the PR

  10. Earthquake Scenario-Based Tsunami Wave Heights in the Eastern Mediterranean and Connected Seas

    Science.gov (United States)

    Necmioglu, Ocal; Özel, Nurcan Meral

    2015-12-01

    We identified a set of tsunami scenario input parameters in a 0.5° × 0.5° uniformly gridded area in the Eastern Mediterranean, Aegean (both for shallow- and intermediate-depth earthquakes) and Black Seas (only shallow earthquakes) and calculated tsunami scenarios using the SWAN-Joint Research Centre (SWAN-JRC) code ( Mader 2004; Annunziato 2007) with 2-arcmin resolution bathymetry data for the range of 6.5—Mwmax with an Mw increment of 0.1 at each grid in order to realize a comprehensive analysis of tsunami wave heights from earthquakes originating in the region. We defined characteristic earthquake source parameters from a compiled set of sources such as existing moment tensor catalogues and various reference studies, together with the Mwmax assigned in the literature, where possible. Results from 2,415 scenarios show that in the Eastern Mediterranean and its connected seas (Aegean and Black Sea), shallow earthquakes with Mw ≥ 6.5 may result in coastal wave heights of 0.5 m, whereas the same wave height would be expected only from intermediate-depth earthquakes with Mw ≥ 7.0 . The distribution of maximum wave heights calculated indicate that tsunami wave heights up to 1 m could be expected in the northern Aegean, whereas in the Black Sea, Cyprus, Levantine coasts, northern Libya, eastern Sicily, southern Italy, and western Greece, up to 3-m wave height could be possible. Crete, the southern Aegean, and the area between northeast Libya and Alexandria (Egypt) is prone to maximum tsunami wave heights of >3 m. Considering that calculations are performed at a minimum bathymetry depth of 20 m, these wave heights may, according to Green's Law, be amplified by a factor of 2 at the coastline. The study can provide a basis for detailed tsunami hazard studies in the region.

  11. Far field tsunami simulations of the 1755 Lisbon earthquake: Implications for tsunami hazard to the U.S. East Coast and the Caribbean

    Science.gov (United States)

    Barkan, R.; ten Brink, Uri S.; Lin, J.

    2009-01-01

    The great Lisbon earthquake of November 1st, 1755 with an estimated moment magnitude of 8.5-9.0 was the most destructive earthquake in European history. The associated tsunami run-up was reported to have reached 5-15??m along the Portuguese and Moroccan coasts and the run-up was significant at the Azores and Madeira Island. Run-up reports from a trans-oceanic tsunami were documented in the Caribbean, Brazil and Newfoundland (Canada). No reports were documented along the U.S. East Coast. Many attempts have been made to characterize the 1755 Lisbon earthquake source using geophysical surveys and modeling the near-field earthquake intensity and tsunami effects. Studying far field effects, as presented in this paper, is advantageous in establishing constraints on source location and strike orientation because trans-oceanic tsunamis are less influenced by near source bathymetry and are unaffected by triggered submarine landslides at the source. Source location, fault orientation and bathymetry are the main elements governing transatlantic tsunami propagation to sites along the U.S. East Coast, much more than distance from the source and continental shelf width. Results of our far and near-field tsunami simulations based on relative amplitude comparison limit the earthquake source area to a region located south of the Gorringe Bank in the center of the Horseshoe Plain. This is in contrast with previously suggested sources such as Marqu??s de Pombal Fault, and Gulf of C??diz Fault, which are farther east of the Horseshoe Plain. The earthquake was likely to be a thrust event on a fault striking ~ 345?? and dipping to the ENE as opposed to the suggested earthquake source of the Gorringe Bank Fault, which trends NE-SW. Gorringe Bank, the Madeira-Tore Rise (MTR), and the Azores appear to have acted as topographic scatterers for tsunami energy, shielding most of the U.S. East Coast from the 1755 Lisbon tsunami. Additional simulations to assess tsunami hazard to the U.S. East

  12. Research regarding evaluation of earthquake and tsunami that preceded it in nuclear reactors

    International Nuclear Information System (INIS)

    2012-01-01

    The 2011 off the Pacific coast of Tohoku Earthquake generated a series of large tsunami waves that struck the east coast of Japan. Several nuclear power facilities were affected by the large multiple tsunami waves. As the result, Fukushima Daiichi 1-4 has progressed to a serious accident. But, integrity evaluation of equipments for tsunami has not been established. Therefore, draft of the Guidelines for tsunami design were formulated with reference to this serious accident in JNES. The action item is as follows. I. Survey of damage caused by the earthquake and design information. To investigate the damage situation of nuclear power plants have been conducted. In addition, to organize the placement information of equipments pertaining to seawater cooling system and emergency power system. And to organize tsunami countermeasures of current nuclear power plants. II. The formation of draft of Guidelines for Tsunami Design. Design policy was formulated in Guidelines for Tsunami Design based on the investigation of survey results of I. (author)

  13. Great Earthquakes, Gigantic Landslides, and the Continuing Enigma of the April Fool's Tsunami of 1946

    Science.gov (United States)

    Fryer, G. J.; Tryon, M. D.

    2005-12-01

    Paleotsunami studies can extend the record of great earthquakes back into prehistory, but what if the historical record itself is ambiguous? There is growing controversy about whether great earthquakes really occur along the Shumagin and Unimak segments of the Alaska-Aleutian system. The last great tsunami there was April 1, 1946, initiated by an earthquake whose magnitude has variously been reported from 7.1 to 8.5. Okal et al (BSSA, 2003) surveyed the near-field runup and concluded there were two sources: a magnitude 8.5 earthquake, which generated a Pacific-wide tsunami but which produced near-field runups no more than 18 m, and an earthquake-triggered slump whose tsunami reached 42 m at Scotch Cap Light near the western end of Unimak Island, but with runup rapidly decaying eastwards. An M8.5 earthquake, however, is incompatible with GPS strain measurements, which indicate that the maximum earthquake size off Unimak is M7.5. We have long contended that near- and far-field tsunamis were the result of a single earthquake-triggered debris avalanche down the Aleutian slope. In 2004 we were part of an expedition to map and explore the landslide, whose location seemed to be very tightly constrained by the known tsunami travel time to Scotch Cap Light. We found that neither our giant landslide nor Okal et al's smaller slump exist within 100 km of the presumed location. The explanation is obvious in retrospect: the tsunami was so large that it crossed the shallow Aleutian shelf as a bore travelling faster than the theoretical long-wave speed (which we had used to fix the location). Any landslide could only have occurred in an unsurveyed area farther east, off Unimak Bight, the central coast of Unimak Island. That location, however, conflicts with Okal et al's measurements of smaller runup along the Bight. We are now convinced that Okal et al confused the 1946 debris line with the lower line left by the 1957 tsunami. They were apparently unaware that the 1946 tsunami

  14. Bodrum-Kos (Turkey-Greece) Mw 6.6 earthquake and tsunami of 20 July 2017: a test for the Mediterranean tsunami warning system

    Science.gov (United States)

    Heidarzadeh, Mohammad; Necmioglu, Ocal; Ishibe, Takeo; Yalciner, Ahmet C.

    2017-12-01

    Various Tsunami Service Providers (TSPs) within the Mediterranean Basin supply tsunami warnings including CAT-INGV (Italy), KOERI-RETMC (Turkey), and NOA/HL-NTWC (Greece). The 20 July 2017 Bodrum-Kos (Turkey-Greece) earthquake (Mw 6.6) and tsunami provided an opportunity to assess the response from these TSPs. Although the Bodrum-Kos tsunami was moderate (e.g., runup of 1.9 m) with little damage to properties, it was the first noticeable tsunami in the Mediterranean Basin since the 21 May 2003 western Mediterranean tsunami. Tsunami waveform analysis revealed that the trough-to-crest height was 34.1 cm at the near-field tide gauge station of Bodrum (Turkey). Tsunami period band was 2-30 min with peak periods at 7-13 min. We proposed a source fault model for this tsunami with the length and width of 25 and 15 km and uniform slip of 0.4 m. Tsunami simulations using both nodal planes produced almost same results in terms of agreement between tsunami observations and simulations. Different TSPs provided tsunami warnings at 10 min (CAT-INGV), 19 min (KOERI-RETMC), and 18 min (NOA/HL-NTWC) after the earthquake origin time. Apart from CAT-INGV, whose initial Mw estimation differed 0.2 units with respect to the final value, the response from the other two TSPs came relatively late compared to the desired warning time of 10 min, given the difficulties for timely and accurate calculation of earthquake magnitude and tsunami impact assessment. It is argued that even if a warning time of 10 min was achieved, it might not have been sufficient for addressing near-field tsunami hazards. Despite considerable progress and achievements made within the upstream components of NEAMTWS (North East Atlantic, Mediterranean and Connected seas Tsunami Warning System), the experience from this moderate tsunami may highlight the need for improving operational capabilities of TSPs, but more importantly for effectively integrating civil protection authorities into NEAMTWS and strengthening

  15. Tsunami simulations of mega-thrust earthquakes in the Nankai–Tonankai Trough (Japan) based on stochastic rupture scenarios

    KAUST Repository

    Goda, Katsuichiro

    2017-02-23

    In this study, earthquake rupture models for future mega-thrust earthquakes in the Nankai–Tonankai subduction zone are developed by incorporating the main characteristics of inverted source models of the 2011 Tohoku earthquake. These scenario ruptures also account for key features of the national tsunami source model for the Nankai–Tonankai earthquake by the Central Disaster Management Council of the Japanese Government. The source models capture a wide range of realistic slip distributions and kinematic rupture processes, reflecting the current best understanding of what may happen due to a future mega-earthquake in the Nankai–Tonankai Trough, and therefore are useful for conducting probabilistic tsunami hazard and risk analysis. A large suite of scenario rupture models is then used to investigate the variability of tsunami effects in coastal areas, such as offshore tsunami wave heights and onshore inundation depths, due to realistic variations in source characteristics. Such investigations are particularly valuable for tsunami hazard mapping and evacuation planning in municipalities along the Nankai–Tonankai coast.

  16. Far-field tsunami of 2017 Mw 8.1 Tehuantepec, Mexico earthquake recorded by Chilean tide gauge network: Implications for tsunami warning systems

    Science.gov (United States)

    González-Carrasco, J. F.; Benavente, R. F.; Zelaya, C.; Núñez, C.; Gonzalez, G.

    2017-12-01

    The 2017 Mw 8.1, Tehuantepec earthquake generated a moderated tsunami, which was registered in near-field tide gauges network activating a tsunami threat state for Mexico issued by PTWC. In the case of Chile, the forecast of tsunami waves indicate amplitudes less than 0.3 meters above the tide level, advising an informative state of threat, without activation of evacuation procedures. Nevertheless, during sea level monitoring of network we detect wave amplitudes (> 0.3 m) indicating a possible change of threat state. Finally, NTWS maintains informative level of threat based on mathematical filtering analysis of sea level records. After 2010 Mw 8.8, Maule earthquake, the Chilean National Tsunami Warning System (NTWS) has increased its observational capabilities to improve early response. Most important operational efforts have focused on strengthening tide gauge network for national area of responsibility. Furthermore, technological initiatives as Integrated Tsunami Prediction and Warning System (SIPAT) has segmented the area of responsibility in blocks to focus early warning and evacuation procedures on most affected coastal areas, while maintaining an informative state for distant areas of near-field earthquake. In the case of far-field events, NTWS follow the recommendations proposed by Pacific Tsunami Warning Center (PTWC), including a comprehensive monitoring of sea level records, such as tide gauges and DART (Deep-Ocean Assessment and Reporting of Tsunami) buoys, to evaluate the state of tsunami threat in the area of responsibility. The main objective of this work is to analyze the first-order physical processes involved in the far-field propagation and coastal impact of tsunami, including implications for decision-making of NTWS. To explore our main question, we construct a finite-fault model of the 2017, Mw 8.1 Tehuantepec earthquake. We employ the rupture model to simulate a transoceanic tsunami modeled by Neowave2D. We generate synthetic time series at

  17. Field Investigations and a Tsunami Modeling for the 1766 Marmara Sea Earthquake, Turkey

    Science.gov (United States)

    Aykurt Vardar, H.; Altinok, Y.; Alpar, B.; Unlu, S.; Yalciner, A. C.

    2016-12-01

    Turkey is located on one of the world's most hazardous earthquake zones. The northern branch of the North Anatolian fault beneath the Sea of Marmara, where the population is most concentrated, is the most active fault branch at least since late Pliocene. The Sea of Marmara region has been affected by many large tsunamigenic earthquakes; the most destructive ones are 549, 553, 557, 740, 989, 1332, 1343, 1509, 1766, 1894, 1912 and 1999 events. In order to understand and determine the tsunami potential and their possible effects along the coasts of this inland sea, detailed documentary, geophysical and numerical modelling studies are needed on the past earthquakes and their associated tsunamis whose effects are presently unknown.On the northern coast of the Sea of Marmara region, the Kucukcekmece Lagoon has a high potential to trap and preserve tsunami deposits. Within the scope of this study, lithological content, composition and sources of organic matters in the lagoon's bottom sediments were studied along a 4.63 m-long piston core recovered from the SE margin of the lagoon. The sedimentary composition and possible sources of the organic matters along the core were analysed and their results were correlated with the historical events on the basis of dating results. Finally, a tsunami scenario was tested for May 22nd 1766 Marmara Sea Earthquake by using a widely used tsunami simulation model called NAMIDANCE. The results show that the candidate tsunami deposits at the depths of 180-200 cm below the lagoons bottom were related with the 1766 (May) earthquake. This work was supported by the Scientific Research Projects Coordination Unit of Istanbul University (Project 6384) and by the EU project TRANSFER for coring.

  18. Emergency management response to a warning-level Alaska-source tsunami impacting California: Chapter J in The SAFRR (Science Application for Risk Reduction) Tsunami Scenario

    Science.gov (United States)

    Miller, Kevin M.; Long, Kate

    2013-01-01

    This chapter is directed towards two audiences: Firstly, it targets nonemergency management readers, providing them with insight on the process and challenges facing emergency managers in responding to tsunami Warning, particularly given this “short fuse” scenario. It is called “short fuse” because there is only a 5.5-hour window following the earthquake before arrival of the tsunami within which to evaluate the threat, disseminate alert and warning messages, and respond. This action initiates a period when crisis communication is of paramount importance. An additional dynamic that is important to note is that within 15 minutes of the earthquake, the National Oceanic and Atmospheric Administration (NOAA) and the National Weather Service (NWS) will issue alert bulletins for the entire Pacific Coast. This is one-half the time actually presented by recent tsunamis from Japan, Chile, and Samoa. Second, the chapter provides emergency managers at all levels with insights into key considerations they may need to address in order to augment their existing plans and effectively respond to tsunami events. We look at emergency management response to the tsunami threat from three perspectives:“Top Down” (Threat analysis and Alert/Warning information from the Federal agency charged with Alert and Warning) “Bottom Up” (Emergency management’s Incident Command approach to responding to emergencies and disasters based on the needs of impacted local jurisdictions) “Across Time” (From the initiating earthquake event through emergency response) We focus on these questions: What are the government roles, relationships, and products that support Tsunami Alert and Warning dissemination? (Emergency Planning and Preparedness.) What roles, relationships, and products support emergency management response to Tsunami Warning and impact? (Engendering prudent public safety response.) What are the key emergency management activities, considerations, and challenges brought

  19. Characteristics and damage investigation of the 1998 Papua New Guinea earthquake tsunami

    International Nuclear Information System (INIS)

    Matsuyama, Masashi

    1998-01-01

    On 17 July, 1998, an earthquake with moment magnitude Mw 7.1 (estimated by Harvard Univ.) occurred at 18:49 (local time) on the north west part of Papua New Guinea. Several minutes after the main shock, huge tsunami attacked the north coast of Sissano and Malol, where the coast is composed of straight beach with white sand, and about 7,000 people had lived in high floor wooden houses. Due to the tsunami, more than 2,000 people were killed. To investigate damage by the tsunami, a survey team of seven members was organized in Japan. The author took part in the survey team, which was headed by Prof. Kawata, of Kyoto University. We stayed in the Papua New Guinea from 30th July through 10th August 1998 to investigate the maximum water level, to interview the people about the phenomena caused by the earthquake and the tsunami, and to set three seismographs. These results imply that: (1) By main shock, an earthquake intensity of 6 on the Richter scale was felt in Sissano and Malol. In the coast area near Sissano and Malol, liquefaction took place. (2) More than 2,000 people were killed mainly due to the tsunami. (3) The maximum water level of the tsunami was about 15 m. (4) It seems that the tsunami caused not only by crustal movement, but also by other factors. This is suggested by the fact that the measured maximum water level was beyond 10 times larger than the estimated one, which was calculated by numerical simulation based on known fault parameters. It is highly probable that a submarine landslide was one of main factors which amplified the tsunami. (author)

  20. The 8 September 2017 Tsunami Triggered by the M w 8.2 Intraplate Earthquake, Chiapas, Mexico

    Science.gov (United States)

    Ramírez-Herrera, María Teresa; Corona, Néstor; Ruiz-Angulo, Angel; Melgar, Diego; Zavala-Hidalgo, Jorge

    2018-01-01

    The 8 September 2017, M w 8.2 earthquake offshore Chiapas, Mexico, is the largest earthquake in recorded history in Chiapas since 1902. It caused damage in the states of Oaxaca, Chiapas and Tabasco, including more than 100 fatalities, over 1.5 million people were affected, and 41,000 homes were damaged in the state of Chiapas alone. This earthquake, an intraplate event on a normal fault on the oceanic subducting plate, generated a tsunami recorded at several tide gauge stations in Mexico and on the Pacific Ocean. Here, we report the physical effects of the tsunami on the Chiapas coast and analyze the societal implications of this tsunami on the basis of our post-tsunami field survey. The associated tsunami waves were recorded first at Huatulco tide gauge station at 5:04 (GMT) 12 min after the earthquake. We covered ground observations along 41 km of the coast of Chiapas, encompassing the sites with the highest projected wave heights based on our preliminary tsunami model (maximum tsunami amplitudes between 94.5° and 93.0°W). Runup and inundation distances were measured along eight sites. The tsunami occurred at low tide. The maximum runup was 3 m at Boca del Cielo, and maximum inundation distance was 190 m in Puerto Arista, corresponding to the coast in front of the epicenter and in the central sector of the Gulf of Tehuantepec. Tsunami scour and erosion was evident along the Chiapas coast. Tsunami deposits, mainly sand, reached up to 32 cm thickness thinning landward up to 172 m distance.

  1. Crisis management of tohoku; Japan earthquake and tsunami, 11 march 2011.

    Science.gov (United States)

    Zaré, M; Afrouz, S Ghaychi

    2012-01-01

    The huge earthquake in 11 March 2012 which followed by a destructive tsunami in Japan was largest recorded earthquake in the history. Japan is pioneer in disaster management, especially earthquakes. How this developed country faced this disaster, which had significant worldwide effects? The humanitarian behavior of the Japanese people amazingly wondered the word's media, meanwhile the management of government and authorities showed some deficiencies. The impact of the disaster is followed up after the event and the different impacts are tried to be analyzed in different sectors. The situation one year after Japan 2011 earthquake and Tsunami is overviewed. The reason of Japanese plans failure was the scale of tsunami, having higher waves than what was assumed, especially in the design of the Nuclear Power Plant. Japanese authorities considered economic benefits more than safety and moral factors exacerbate the situation. Major lessons to be learnt are 1) the effectiveness of disaster management should be restudied in all hazardous countries; 2) the importance of the high-Tech early-warning systems in reducing risk; 3) Reconsidering of extreme values expected/possible hazard and risk levels is necessary; 4) Morality and might be taken as an important factor in disaster management; 5) Sustainable development should be taken as the basis for reconstruction after disaster.

  2. The 1946 Unimak Tsunami Earthquake Area: revised tectonic structure in reprocessed seismic images and a suspect near field tsunami source

    Science.gov (United States)

    Miller, John J.; von Huene, Roland E.; Ryan, Holly F.

    2014-01-01

    In 1946 at Unimak Pass, Alaska, a tsunami destroyed the lighthouse at Scotch Cap, Unimak Island, took 159 lives on the Hawaiian Islands, damaged island coastal facilities across the south Pacific, and destroyed a hut in Antarctica. The tsunami magnitude of 9.3 is comparable to the magnitude 9.1 tsunami that devastated the Tohoku coast of Japan in 2011. Both causative earthquake epicenters occurred in shallow reaches of the subduction zone. Contractile tectonism along the Alaska margin presumably generated the far-field tsunami by producing a seafloor elevation change. However, the Scotch Cap lighthouse was destroyed by a near-field tsunami that was probably generated by a coeval large undersea landslide, yet bathymetric surveys showed no fresh large landslide scar. We investigated this problem by reprocessing five seismic lines, presented here as high-resolution graphic images, both uninterpreted and interpreted, and available for the reader to download. In addition, the processed seismic data for each line are available for download as seismic industry-standard SEG-Y files. One line, processed through prestack depth migration, crosses a 10 × 15 kilometer and 800-meter-high hill presumed previously to be basement, but that instead is composed of stratified rock superimposed on the slope sediment. This image and multibeam bathymetry illustrate a slide block that could have sourced the 1946 near-field tsunami because it is positioned within a distance determined by the time between earthquake shaking and the tsunami arrival at Scotch Cap and is consistent with the local extent of high runup of 42 meters along the adjacent Alaskan coast. The Unimak/Scotch Cap margin is structurally similar to the 2011 Tohoku tsunamigenic margin where a large landslide at the trench, coeval with the Tohoku earthquake, has been documented. Further study can improve our understanding of tsunami sources along Alaska’s erosional margins.

  3. The Great East-Japan Earthquake and devastating tsunami. An update and lessons from the past great earthquakes in Japan since 1923

    International Nuclear Information System (INIS)

    Ishigaki, Akemi; Higashi, Hikari; Sakamoto, Takako; Shibahara, Shigeki

    2013-01-01

    Japan has a long history of fighting against great earthquakes that cause structural damage/collapses, fires and/or tsunami. On March 11, 2011 at 14:46 (Friday), the Great East-Japan Earthquake (magnitude 9.0) attacked the Tohoku region (northeastern Japan), which includes Sendai City. The earthquake generated a devastating tsunami, leading to unprecedented disasters (∼18,500 victims) in coastal areas of Iwate, Miyagi and Fukushima prefectures, despite the fact that people living in the Tohoku region are well trained for tsunami-evacuation procedures, with the mindset of ''Tsunami, ten-den-ko.'' This code means that each person should evacuate individually upon an earthquake. Sharing this rule, children and parents can escape separately from schools, houses or workplaces, without worrying about each other. The concept of ten-den-ko (individual evacuation) is helpful for people living in coastal areas of earthquake-prone zones around the world. It is also important to construct safe evacuation centers, because the March 11 th tsunami killed people who had evacuated to evacuation sites. We summarize the current conditions of people living in the disaster-stricken areas, including the consequences of the Fukushima nuclear accident. We also describe the disaster responses as the publisher of the Tohoku Journal of Experimental Medicine (TJEM), located in Sendai, with online support from Tokyo. In 1923, the Great Kanto Earthquake (magnitude 7.9) evoked a massive fire that destroyed large areas of Tokyo (∼105,000 victims), including the print company for TJEM, but the Wistar Institute printed three TJEM issues in 1923 in Philadelphia. Mutual aid relationships should be established between distant cities to survive future disasters. (author)

  4. The Great East-Japan Earthquake and devastating tsunami: an update and lessons from the past Great Earthquakes in Japan since 1923.

    Science.gov (United States)

    Ishigaki, Akemi; Higashi, Hikari; Sakamoto, Takako; Shibahara, Shigeki

    2013-04-01

    Japan has a long history of fighting against great earthquakes that cause structural damage/collapses, fires and/or tsunami. On March 11, 2011 at 14:46 (Friday), the Great East-Japan Earthquake (magnitude 9.0) attacked the Tohoku region (northeastern Japan), which includes Sendai City. The earthquake generated a devastating tsunami, leading to unprecedented disasters (~18,500 victims) in coastal areas of Iwate, Miyagi and Fukushima prefectures, despite the fact that people living in the Tohoku region are well trained for tsunami-evacuation procedures, with the mindset of "Tsunami, ten-den-ko." This code means that each person should evacuate individually upon an earthquake. Sharing this rule, children and parents can escape separately from schools, houses or workplaces, without worrying about each other. The concept of ten-den-ko (individual evacuation) is helpful for people living in coastal areas of earthquake-prone zones around the world. It is also important to construct safe evacuation centers, because the March 11(th) tsunami killed people who had evacuated to evacuation sites. We summarize the current conditions of people living in the disaster-stricken areas, including the consequences of the Fukushima nuclear accident. We also describe the disaster responses as the publisher of the Tohoku Journal of Experimental Medicine (TJEM), located in Sendai, with online support from Tokyo. In 1923, the Great Kanto Earthquake (magnitude 7.9) evoked a massive fire that destroyed large areas of Tokyo (~105,000 victims), including the print company for TJEM, but the Wistar Institute printed three TJEM issues in 1923 in Philadelphia. Mutual aid relationships should be established between distant cities to survive future disasters.

  5. Tsunami on Sanriku Coast in 1586: Orphan or Ghost Tsunami ?

    Science.gov (United States)

    Satake, K.

    2017-12-01

    The Peruvian earthquake on July 9, 1586 was the oldest earthquake that damaged Lima. The tsunami height was assigned as 24 m in Callao and 1-2 m in Miyagi prefecture in Japan by Soloviev and Go (1975). Dorbath et al. (1990) studied historical earthquakes in Peru and estimated that the 1586 earthquake was similar to the 1974 event (Mw 8.1) with source length of 175 km. They referred two different tsunami heights, 3. 7m and 24 m, in Callao, and judged that the latter was exaggerated. Okal et al. (2006) could not make a source model to explain both tsunami heights in Callao and Japan. More recently, Butler et al. (2017) estimated the age of coral boulders in Hawaii as AD 1572 +/- 21, speculated the tsunami source in Aleutians, and attributed it to the source of the 1586 tsunami in Japan. Historical tsunamis, both near-field and far-field, have been documented along the Sanriku coast since 1586 (e.g., Watanabe, 1998). However, there is no written document for the 1586 tsunami (Tsuji et al., 2013). Ninomiya (1960) compiled the historical tsunami records on the Sanriku coast soon after the 1960 Chilean tsunami, and correlated the legend of tsunami in Tokura with the 1586 Peruvian earthquake, although he noted that the dates were different. About the legend, he referred to Kunitomi(1933) who compiled historical tsunami data after the 1933 Showa Sanriku tsunami. Kunitomi referred to "Tsunami history of Miyagi prefecture" published after the 1896 Meiji Sanriku tsunami. "Tsunami history" described the earthquake and tsunami damage of Tensho earthquake on January 18 (Gregorian),1586 in central Japan, and correlated the tsunami legend in Tokura on June 30, 1586 (G). Following the 2011 Tohoku tsunami, tsunami legend in Tokura was studied again (Ebina, 2015). A local person published a story he heard from his grandfather that many small valleys were named following the 1611 tsunami, which inundated further inland than the 2011 tsunami. Ebina (2015), based on historical documents

  6. Evaluation of seismic source, ground motion, tsunami based on the Tohoku earthquake

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2012-08-15

    Our source models for the Mw9.0 Tohoku earthquake either inferred using tsunami data or from seismic data are featured with large slip along the Japan Trench. Our results indicated that the tsunami water levels at the Fukushima Daiichi and Daini NPPs were dominated by the large slip along the Japan Trench. Our analysis suggested that the difference in water levels at these two sites were caused by the waveform overlap effects due to delays of rupture starting times and wave propagation time. It also follows that the short period ground motions recorded during such an Mw9.0 mega thrust earthquake were comparable with those of an Mw8.0 earthquake. (author)

  7. Observing Traveling Ionospheric Disturbances Caused by Tsunamis Using GPS TEC Measurements

    Science.gov (United States)

    Galvan, David A.; Komjathy, Attila; Hickey, Michael; Foster, James; Mannucci, Anthony J.

    2010-01-01

    Ground-based Global Positioning System (GPS) measurements of ionospheric Total Electron Content (TEC) show variations consistent with atmospheric internal gravity waves caused by ocean tsunamis following two recent seismic events: the American Samoa earthquake of September 29, 2009, and the Chile earthquake of February 27, 2010. Fluctuations in TEC correlated in time, space, and wave properties with these tsunamis were observed in TEC estimates processed using JPL's Global Ionospheric Mapping Software. These TEC estimates were band-pass filtered to remove ionospheric TEC variations with wavelengths and periods outside the typical range of internal gravity waves caused by tsunamis. Observable variations in TEC appear correlated with the tsunamis in certain locations, but not in others. Where variations are observed, the typical amplitude tends to be on the order of 1% of the background TEC value. Variations with amplitudes 0.1 - 0.2 TECU are observable with periods and timing affiliated with the tsunami. These observations are compared to estimates of expected tsunami-driven TEC variations produced by Embry Riddle Aeronautical University's Spectral Full Wave Model, an atmosphere-ionosphere coupling model, and found to be in good agreement in some locations, though there are cases when the model predicts an observable tsunami-driven signature and none is observed. These TEC variations are not always seen when a tsunami is present, but in these two events the regions where a strong ocean tsunami was observed did coincide with clear TEC observations, while a lack of clear TEC observations coincided with smaller tsunami amplitudes. There exists the potential to apply these detection techniques to real-time GPS TEC data, providing estimates of tsunami speed and amplitude that may be useful for early warning systems.

  8. Application of a Tsunami Warning Message Metric to refine NOAA NWS Tsunami Warning Messages

    Science.gov (United States)

    Gregg, C. E.; Johnston, D.; Sorensen, J.; Whitmore, P.

    2013-12-01

    In 2010, the U.S. National Weather Service (NWS) funded a three year project to integrate social science into their Tsunami Program. One of three primary requirements of the grant was to make improvements to tsunami warning messages of the NWS' two Tsunami Warning Centers- the West Coast/Alaska Tsunami Warning Center (WCATWC) in Palmer, Alaska and the Pacific Tsunami Warning Center (PTWC) in Ewa Beach, Hawaii. We conducted focus group meetings with a purposive sample of local, state and Federal stakeholders and emergency managers in six states (AK, WA, OR, CA, HI and NC) and two US Territories (US Virgin Islands and American Samoa) to qualitatively asses information needs in tsunami warning messages using WCATWC tsunami messages for the March 2011 Tohoku earthquake and tsunami event. We also reviewed research literature on behavioral response to warnings to develop a tsunami warning message metric that could be used to guide revisions to tsunami warning messages of both warning centers. The message metric is divided into categories of Message Content, Style, Order and Formatting and Receiver Characteristics. A message is evaluated by cross-referencing the message with the operational definitions of metric factors. Findings are then used to guide revisions of the message until the characteristics of each factor are met. Using findings from this project and findings from a parallel NWS Warning Tiger Team study led by T. Nicolini, the WCATWC implemented the first of two phases of revisions to their warning messages in November 2012. A second phase of additional changes, which will fully implement the redesign of messages based on the metric, is in progress. The resulting messages will reflect current state-of-the-art knowledge on warning message effectiveness. Here we present the message metric; evidence-based rational for message factors; and examples of previous, existing and proposed messages.

  9. Smartphone-Based Earthquake and Tsunami Early Warning in Chile

    Science.gov (United States)

    Brooks, B. A.; Baez, J. C.; Ericksen, T.; Barrientos, S. E.; Minson, S. E.; Duncan, C.; Guillemot, C.; Smith, D.; Boese, M.; Cochran, E. S.; Murray, J. R.; Langbein, J. O.; Glennie, C. L.; Dueitt, J.; Parra, H.

    2016-12-01

    Many locations around the world face high seismic hazard, but do not have the resources required to establish traditional earthquake and tsunami warning systems (E/TEW) that utilize scientific grade seismological sensors. MEMs accelerometers and GPS chips embedded in, or added inexpensively to, smartphones are sensitive enough to provide robust E/TEW if they are deployed in sufficient numbers. We report on a pilot project in Chile, one of the most productive earthquake regions world-wide. There, magnitude 7.5+ earthquakes occurring roughly every 1.5 years and larger tsunamigenic events pose significant local and trans-Pacific hazard. The smartphone-based network described here is being deployed in parallel to the build-out of a scientific-grade network for E/TEW. Our sensor package comprises a smartphone with internal MEMS and an external GPS chipset that provides satellite-based augmented positioning and phase-smoothing. Each station is independent of local infrastructure, they are solar-powered and rely on cellular SIM cards for communications. An Android app performs initial onboard processing and transmits both accelerometer and GPS data to a server employing the FinDer-BEFORES algorithm to detect earthquakes, producing an acceleration-based line source model for smaller magnitude earthquakes or a joint seismic-geodetic finite-fault distributed slip model for sufficiently large magnitude earthquakes. Either source model provides accurate ground shaking forecasts, while distributed slip models for larger offshore earthquakes can be used to infer seafloor deformation for local tsunami warning. The network will comprise 50 stations by Sept. 2016 and 100 stations by Dec. 2016. Since Nov. 2015, batch processing has detected, located, and estimated the magnitude for Mw>5 earthquakes. Operational since June, 2016, we have successfully detected two earthquakes > M5 (M5.5, M5.1) that occurred within 100km of our network while producing zero false alarms.

  10. Tsunami Hazard Assessment of Coastal South Africa Based on Mega-Earthquakes of Remote Subduction Zones

    Science.gov (United States)

    Kijko, Andrzej; Smit, Ansie; Papadopoulos, Gerassimos A.; Novikova, Tatyana

    2017-11-01

    After the mega-earthquakes and concomitant devastating tsunamis in Sumatra (2004) and Japan (2011), we launched an investigation into the potential risk of tsunami hazard to the coastal cities of South Africa. This paper presents the analysis of the seismic hazard of seismogenic sources that could potentially generate tsunamis, as well as the analysis of the tsunami hazard to coastal areas of South Africa. The subduction zones of Makran, South Sandwich Island, Sumatra, and the Andaman Islands were identified as possible sources of mega-earthquakes and tsunamis that could affect the African coast. Numerical tsunami simulations were used to investigate the realistic and worst-case scenarios that could be generated by these subduction zones. The simulated tsunami amplitudes and run-up heights calculated for the coastal cities of Cape Town, Durban, and Port Elizabeth are relatively small and therefore pose no real risk to the South African coast. However, only distant tsunamigenic sources were considered and the results should therefore be viewed as preliminary.

  11. Tsunami Hazard Assessment of Coastal South Africa Based on Mega-Earthquakes of Remote Subduction Zones

    Science.gov (United States)

    Kijko, Andrzej; Smit, Ansie; Papadopoulos, Gerassimos A.; Novikova, Tatyana

    2018-04-01

    After the mega-earthquakes and concomitant devastating tsunamis in Sumatra (2004) and Japan (2011), we launched an investigation into the potential risk of tsunami hazard to the coastal cities of South Africa. This paper presents the analysis of the seismic hazard of seismogenic sources that could potentially generate tsunamis, as well as the analysis of the tsunami hazard to coastal areas of South Africa. The subduction zones of Makran, South Sandwich Island, Sumatra, and the Andaman Islands were identified as possible sources of mega-earthquakes and tsunamis that could affect the African coast. Numerical tsunami simulations were used to investigate the realistic and worst-case scenarios that could be generated by these subduction zones. The simulated tsunami amplitudes and run-up heights calculated for the coastal cities of Cape Town, Durban, and Port Elizabeth are relatively small and therefore pose no real risk to the South African coast. However, only distant tsunamigenic sources were considered and the results should therefore be viewed as preliminary.

  12. Tsunamis triggered by the 12 January 2010 Earthquake in Haiti

    Science.gov (United States)

    Fritz, H. M.; Hillaire, J. V.; Molière, E.; Mohammed, F.; Wei, Y.

    2010-12-01

    On 12 January 2010 a magnitude Mw 7.0 earthquake occurred 25 km west-southwest of Haiti’s Capital of Port-au-Prince, which resulted in more than 230,000 fatalities. In addition tsunami waves triggered by the earthquake caused at least 3 fatalities at Petit Paradis. Unfortunately, the people of Haiti had neither ancestral knowledge nor educational awareness of tsunami hazards despite the 1946 Dominican Republic tsunami at Hispaniola’s northeast coast. In sharp contrast Sri Lankan UN-soldiers on duty at Jacmel self-evacuated given the memory of the 2004 Indian Ocean tsunami. The International Tsunami Survey Team (ITST) documented flow depths, runup heights, inundation distances, sediment deposition, damage patterns at various scales, and performance of the man-made infrastructure and impact on the natural environment. The 31 January to 7 February 2010 ITST covered the greater Bay of Port-au-Prince and more than 100 km of Hispaniola’s south coast between Pedernales, Dominican Republic and Jacmel, Haiti. The Hispaniola survey data includes more than 20 runup and flow depth measurements. The tsunami impacts peaked with maximum flow depths exceeding 3 m both at Petit Paradis inside the Bay of Grand Goâve located 45 km west-southwest of Port-au-Prince and at Jacmel on Haiti’s south coast. A significant variation in tsunami impact was observed on Hispaniola and tsunami runup of more than 1 m was still observed at Pedernales in the Dominican Republic. Jacmel, which is near the center of the south coast, represents an unfortunate example of a village and harbor that was located for protection from storm waves but is vulnerable to tsunami waves with runup doubling from the entrance to the head of the bay. Inundation and damage was limited to less than 100 m inland at both Jacmel and Petit Paradis. Differences in wave period were documented between the tsunami waves at Petit Paradis and Jacmel. The Petit Paradis tsunami is attributed to a coastal submarine landslide

  13. Tsunami Simulations in the Western Makran Using Hypothetical Heterogeneous Source Models from World's Great Earthquakes

    Science.gov (United States)

    Rashidi, Amin; Shomali, Zaher Hossein; Keshavarz Farajkhah, Nasser

    2018-04-01

    The western segment of Makran subduction zone is characterized with almost no major seismicity and no large earthquake for several centuries. A possible episode for this behavior is that this segment is currently locked accumulating energy to generate possible great future earthquakes. Taking into account this assumption, a hypothetical rupture area is considered in the western Makran to set different tsunamigenic scenarios. Slip distribution models of four recent tsunamigenic earthquakes, i.e. 2015 Chile M w 8.3, 2011 Tohoku-Oki M w 9.0 (using two different scenarios) and 2006 Kuril Islands M w 8.3, are scaled into the rupture area in the western Makran zone. The numerical modeling is performed to evaluate near-field and far-field tsunami hazards. Heterogeneity in slip distribution results in higher tsunami amplitudes. However, its effect reduces from local tsunamis to regional and distant tsunamis. Among all considered scenarios for the western Makran, only a similar tsunamigenic earthquake to the 2011 Tohoku-Oki event can re-produce a significant far-field tsunami and is considered as the worst case scenario. The potential of a tsunamigenic source is dominated by the degree of slip heterogeneity and the location of greatest slip on the rupture area. For the scenarios with similar slip patterns, the mean slip controls their relative power. Our conclusions also indicate that along the entire Makran coasts, the southeastern coast of Iran is the most vulnerable area subjected to tsunami hazard.

  14. Tsunami Simulations in the Western Makran Using Hypothetical Heterogeneous Source Models from World's Great Earthquakes

    Science.gov (United States)

    Rashidi, Amin; Shomali, Zaher Hossein; Keshavarz Farajkhah, Nasser

    2018-03-01

    The western segment of Makran subduction zone is characterized with almost no major seismicity and no large earthquake for several centuries. A possible episode for this behavior is that this segment is currently locked accumulating energy to generate possible great future earthquakes. Taking into account this assumption, a hypothetical rupture area is considered in the western Makran to set different tsunamigenic scenarios. Slip distribution models of four recent tsunamigenic earthquakes, i.e. 2015 Chile M w 8.3, 2011 Tohoku-Oki M w 9.0 (using two different scenarios) and 2006 Kuril Islands M w 8.3, are scaled into the rupture area in the western Makran zone. The numerical modeling is performed to evaluate near-field and far-field tsunami hazards. Heterogeneity in slip distribution results in higher tsunami amplitudes. However, its effect reduces from local tsunamis to regional and distant tsunamis. Among all considered scenarios for the western Makran, only a similar tsunamigenic earthquake to the 2011 Tohoku-Oki event can re-produce a significant far-field tsunami and is considered as the worst case scenario. The potential of a tsunamigenic source is dominated by the degree of slip heterogeneity and the location of greatest slip on the rupture area. For the scenarios with similar slip patterns, the mean slip controls their relative power. Our conclusions also indicate that along the entire Makran coasts, the southeastern coast of Iran is the most vulnerable area subjected to tsunami hazard.

  15. Earthquake and Tsunami Disaster Mitigation in the Marmara Region and Disaster Education in Turkey Part3

    Science.gov (United States)

    Kaneda, Yoshiyuki; Ozener, Haluk; Meral Ozel, Nurcan; Kalafat, Dogan; Ozgur Citak, Seckin; Takahashi, Narumi; Hori, Takane; Hori, Muneo; Sakamoto, Mayumi; Pinar, Ali; Oguz Ozel, Asim; Cevdet Yalciner, Ahmet; Tanircan, Gulum; Demirtas, Ahmet

    2017-04-01

    There have been many destructive earthquakes and tsunamis in the world.The recent events are, 2011 East Japan Earthquake/Tsunami in Japan, 2015 Nepal Earthquake and 2016 Kumamoto Earthquake in Japan, and so on. And very recently a destructive earthquake occurred in Central Italy. In Turkey, the 1999 Izmit Earthquake as the destructive earthquake occurred along the North Anatolian Fault (NAF). The NAF crosses the Sea of Marmara and the only "seismic gap" remains beneath the Sea of Marmara. Istanbul with high population similar to Tokyo in Japan, is located around the Sea of Marmara where fatal damages expected to be generated as compound damages including Tsunami and liquefaction, when the next destructive Marmara Earthquake occurs. The seismic risk of Istanbul seems to be under the similar risk condition as Tokyo in case of Nankai Trough earthquake and metropolitan earthquake. It was considered that Japanese and Turkish researchers can share their own experiences during past damaging earthquakes and can prepare for the future large earthquakes in cooperation with each other. Therefore, in 2013 the two countries, Japan and Turkey made an agreement to start a multidisciplinary research project, MarDiM SATREPS. The Project runs researches to aim to raise the preparedness for possible large-scale earthquake and Tsunami disasters in Marmara Region and it has four research groups with the following goals. 1) The first one is Marmara Earthquake Source region observational research group. This group has 4 sub-groups such as Seismicity, Geodesy, Electromagnetics and Trench analyses. Preliminary results such as seismicity and crustal deformation on the sea floor in Sea of Marmara have already achieved. 2) The second group focuses on scenario researches of earthquake occurrence along the North Anatolia Fault and precise tsunami simulation in the Marmara region. Research results from this group are to be the model of earthquake occurrence scenario in Sea of Marmara and the

  16. The Role of Near-Shore Bathymetry During Tsunami Inundation in a Reef Island Setting: A Case Study of Tutuila Island

    Science.gov (United States)

    Dilmen, Derya I.; Roe, Gerard H.; Wei, Yong; Titov, Vasily V.

    2018-04-01

    On September 29, 2009 at 17:48 UTC, an M w = 8.1 earthquake in the Tonga Trench generated a tsunami that caused heavy damage across Samoa, American Samoa, and Tonga. One of the worst hits was the volcanic island of Tutuila in American Samoa. Tutuila has a typical tropical island bathymetry setting influenced by coral reefs, and so the event provided an opportunity to evaluate the relationship between tsunami dynamics and the bathymetry in that typical island environment. Previous work has come to differing conclusions regarding how coral reefs affect tsunami dynamics through their influence on bathymetry and dissipation. This study presents numerical simulations of this event with a focus on two main issues: first, how roughness variations affect tsunami run-up and whether different values of Manning's roughness parameter, n, improve the simulated run-up compared to observations; and second, how depth variations in the shelf bathymetry with coral reefs control run-up and inundation on the island coastlines they shield. We find that no single value of n provides a uniformly good match to all observations; and we find substantial bay-to-bay variations in the impact of varying n. The results suggest that there are aspects of tsunami wave dissipation which are not captured by a simplified drag formulation used in shallow-water waves model. The study also suggests that the primary impact of removing the near-shore bathymetry in coral reef environment is to reduce run-up, from which we conclude that, at least in this setting, the impact of the near-shore bathymetry is to increase run-up and inundation.

  17. The Role of Near-Shore Bathymetry During Tsunami Inundation in a Reef Island Setting: A Case Study of Tutuila Island

    Science.gov (United States)

    Dilmen, Derya I.; Roe, Gerard H.; Wei, Yong; Titov, Vasily V.

    2018-02-01

    On September 29, 2009 at 17:48 UTC, an M w = 8.1 earthquake in the Tonga Trench generated a tsunami that caused heavy damage across Samoa, American Samoa, and Tonga. One of the worst hits was the volcanic island of Tutuila in American Samoa. Tutuila has a typical tropical island bathymetry setting influenced by coral reefs, and so the event provided an opportunity to evaluate the relationship between tsunami dynamics and the bathymetry in that typical island environment. Previous work has come to differing conclusions regarding how coral reefs affect tsunami dynamics through their influence on bathymetry and dissipation. This study presents numerical simulations of this event with a focus on two main issues: first, how roughness variations affect tsunami run-up and whether different values of Manning's roughness parameter, n, improve the simulated run-up compared to observations; and second, how depth variations in the shelf bathymetry with coral reefs control run-up and inundation on the island coastlines they shield. We find that no single value of n provides a uniformly good match to all observations; and we find substantial bay-to-bay variations in the impact of varying n. The results suggest that there are aspects of tsunami wave dissipation which are not captured by a simplified drag formulation used in shallow-water waves model. The study also suggests that the primary impact of removing the near-shore bathymetry in coral reef environment is to reduce run-up, from which we conclude that, at least in this setting, the impact of the near-shore bathymetry is to increase run-up and inundation.

  18. What happened at Fukushima Daiichi Nuclear Power Plants. Verification of effects of earthquake and resulting tsunami

    International Nuclear Information System (INIS)

    Yamazaki, Tatsuhiro

    2012-01-01

    At 14:46 on March 11, 2011, the Tohoku District-off the Pacific Ocean Earthquake occurred. The magnitude of this earthquake was 9.0, the largest in Japan's recorded history, and afterwards enormous tsunami struck the Pacific coast of Tohoku District. This great earthquake and resulting tsunami struck the Fukushima Daiichi Nuclear Power Plants (NPPs) of Tokyo Electric Power Co. (TEPCO), whose cooling function was lost and suffered a severe nuclear accident. This article described the mechanism and safety measure of BWR type NPPs and verified how the great earthquake and resulting tsunami affected NPPs. Progression of the accident at Fukushima Daiichi NPPs was outlined. Damage by the earthquake could not be fully inspected but might not be significant to safety systems. However, the earthquake of longer duration time as much as about 250 sec caused failure of breaker or lightening arrester and also damage on electric facility such as transmission line insulator. Tsunami or inundation height was as high as O.P. (Onahama Pile) +11.5-15.5 m for Unit 1-4 reactor area while designed as O.P. +5.7 m, which caused blackout (power outage) and a reactor core meltdown at Fukushima Daiichi NPPs. (T. Tanaka)

  19. Safety upgrading activities against tsunami, earthquake, and severe accident at Hamaoka NPPs

    International Nuclear Information System (INIS)

    Watanabe, Tetsuya; Wakunaga, Takao; Ishida, Takahisa

    2013-01-01

    As the lessons learned by the Fukushima Daiichi NPPs accident, Chubu Electric Power carried out the Emergency Safety Measures at Hamaoka NPPs immediately, and announced the plan for tsunami countermeasures including the construction of 18m-height tsunami protection wall in July 2011. Furthermore, the company announced the additional severe accident and tsunami countermeasures, and etc. in December 2012 and in April 2013, such as the installation of Filtered Containment Venting System and increasing the height of the tsunami protection wall from 18m to 22m. In this paper, we present major safety upgrading activities against tsunami, earthquake and severe accident at Hamaoka NPPs. (author)

  20. Geological evidence for Holocene earthquakes and tsunamis along the Nankai-Suruga Trough, Japan

    Science.gov (United States)

    Garrett, Ed; Fujiwara, Osamu; Garrett, Philip; Heyvaert, Vanessa M. A.; Shishikura, Masanobu; Yokoyama, Yusuke; Hubert-Ferrari, Aurélia; Brückner, Helmut; Nakamura, Atsunori; De Batist, Marc

    2016-04-01

    The Nankai-Suruga Trough, lying immediately south of Japan's densely populated and highly industrialised southern coastline, generates devastating great earthquakes (magnitude > 8). Intense shaking, crustal deformation and tsunami generation accompany these ruptures. Forecasting the hazards associated with future earthquakes along this >700 km long fault requires a comprehensive understanding of past fault behaviour. While the region benefits from a long and detailed historical record, palaeoseismology has the potential to provide a longer-term perspective and additional insights. Here, we summarise the current state of knowledge regarding geological evidence for past earthquakes and tsunamis, incorporating literature originally published in both Japanese and English. This evidence comes from a wide variety of sources, including uplifted marine terraces and biota, marine and lacustrine turbidites, liquefaction features, subsided marshes and tsunami deposits in coastal lakes and lowlands. We enhance available results with new age modelling approaches. While publications describe proposed evidence from > 70 sites, only a limited number provide compelling, well-dated evidence. The best available records allow us to map the most likely rupture zones of eleven earthquakes occurring during the historical period. Our spatiotemporal compilation suggests the AD 1707 earthquake ruptured almost the full length of the subduction zone and that earthquakes in AD 1361 and 684 were predecessors of similar magnitude. Intervening earthquakes were of lesser magnitude, highlighting variability in rupture mode. Recurrence intervals for ruptures of the a single seismic segment range from less than 100 to more than 450 years during the historical period. Over longer timescales, palaeoseismic evidence suggests intervals ranging from 100 to 700 years. However, these figures reflect thresholds of evidence creation and preservation as well as genuine recurrence intervals. At present, we have

  1. Burden and Management of Noncommunicable Diseases After Earthquakes and Tsunamis.

    Science.gov (United States)

    Suneja, Amit; Gakh, Maxim; Rutkow, Lainie

    This integrative review examines extant literature assessing the burden and management of noncommunicable diseases 6 months or more after earthquakes and tsunamis. We conducted an integrative review to identify and characterize the strength of published studies about noncommunicable disease-specific outcomes and interventions at least 6 months after an earthquake and/or tsunami. We included disasters that occurred from 2004 to 2016. We focused primarily on the World Health Organization noncommunicable disease designations to define chronic disease, but we also included chronic renal disease, risk factors for noncommunicable diseases, and other chronic diseases or symptoms. After removing duplicates, our search yielded 6,188 articles. Twenty-five articles met our inclusion criteria, some discussing multiple noncommunicable diseases. Results demonstrate that existing medical conditions may worsen and subsequently improve, new diseases may develop, and risk factors, such as weight and cholesterol levels, may increase for several years after an earthquake and/or tsunami. We make 3 recommendations for practitioners and researchers: (1) plan for noncommunicable disease management further into the recovery period of disaster; (2) increase research on the burden of noncommunicable diseases, the treatment modalities employed, resulting population-level outcomes in the postdisaster setting, and existing models to improve stakeholder coordination and action regarding noncommunicable diseases after disasters; and (3) coordinate with preexisting provision networks, especially primary care.

  2. Tsunami inundation variability from stochastic rupture scenarios: Application to multiple inversions of the 2011 Tohoku, Japan earthquake

    KAUST Repository

    Mori, Nobuhito

    2017-06-28

    We develop a framework for assessing the sensitivity and variability of tsunami inundation characteristics for stochastic physics-based scenarios of mega-thrust subduction earthquakes. The method is applied to the 2011 Tohoku, Japan earthquake, and tested against observed inundation maps at several locations along the Tohoku coast, using 11 different, previously published, rupture models for this devastating tsunamgenic earthquake. The earthquake rupture models differ in fault dimension (length and width), geometry (dip, strike and top-edge depth), as well as asperity characteristics (slip heterogeneity on the fault plane). The resulting source variability allows exploring a wide range of tsunami scenarios for an Mw9 mega-thrust subduction earthquake in the Tohoku region to conduct thorough sensitivity analyses and to quantify the inundation variability. The numerical results indicate a strong influence of the reference source models on inundation variability, and demonstrate significant sensitivity of inundation to the details of the rupture realization. Therefore, relying on a single particular earthquake rupture model as a representative case when varying earthquake source characteristics may lead to under-representation of the variability of potential scenarios. Moreover, the proposed framework facilitates the rigorous development of critical scenarios for tsunami hazard and risk assessments, which are particularly useful for tsunami hazard mapping and disaster preparedness planning.

  3. Observations and Modeling of the August 27, 2012 Earthquake and Tsunami affecting El Salvador and Nicaragua

    Science.gov (United States)

    Borrero, Jose C.; Kalligeris, Nikos; Lynett, Patrick J.; Fritz, Hermann M.; Newman, Andrew V.; Convers, Jaime A.

    2014-12-01

    On 27 August 2012 (04:37 UTC, 26 August 10:37 p.m. local time) a magnitude M w = 7.3 earthquake occurred off the coast of El Salvador and generated surprisingly large local tsunami. Following the event, local and international tsunami teams surveyed the tsunami effects in El Salvador and northern Nicaragua. The tsunami reached a maximum height of ~6 m with inundation of up to 340 m inland along a 25 km section of coastline in eastern El Salvador. Less severe inundation was reported in northern Nicaragua. In the far-field, the tsunami was recorded by a DART buoy and tide gauges in several locations of the eastern Pacific Ocean but did not cause any damage. The field measurements and recordings are compared to numerical modeling results using initial conditions of tsunami generation based on finite-fault earthquake and tsunami inversions and a uniform slip model.

  4. A long source area of the 1906 Colombia-Ecuador earthquake estimated from observed tsunami waveforms

    Science.gov (United States)

    Yamanaka, Yusuke; Tanioka, Yuichiro; Shiina, Takahiro

    2017-12-01

    The 1906 Colombia-Ecuador earthquake induced both strong seismic motions and a tsunami, the most destructive earthquake in the history of the Colombia-Ecuador subduction zone. The tsunami propagated across the Pacific Ocean, and its waveforms were observed at tide gauge stations in countries including Panama, Japan, and the USA. This study conducted slip inverse analysis for the 1906 earthquake using these waveforms. A digital dataset of observed tsunami waveforms at the Naos Island (Panama) and Honolulu (USA) tide gauge stations, where the tsunami was clearly observed, was first produced by consulting documents. Next, the two waveforms were applied in an inverse analysis as the target waveform. The results of this analysis indicated that the moment magnitude of the 1906 earthquake ranged from 8.3 to 8.6. Moreover, the dominant slip occurred in the northern part of the assumed source region near the coast of Colombia, where little significant seismicity has occurred, rather than in the southern part. The results also indicated that the source area, with significant slip, covered a long distance, including the southern, central, and northern parts of the region.[Figure not available: see fulltext.

  5. 1881 and 1949 earthquakes at the Chios-Cesme Strait (Aegean Sea and their relation to tsunamis

    Directory of Open Access Journals (Sweden)

    Y. Altinok

    2005-01-01

    Full Text Available The most earthquake-prone areas in the eastern central Aegean Sea are the Izmir Bay, the Karaburun peninsula and the island of Chios. The level of seismic activity and tsunami potential are influenced by the presence of normal faults around the region. There have been about 20 moderate-size earthquakes from 496 BC to 1949 AD. Among these earthquakes, the ones on the dates 20 March 1389, 13 November 1856, 19/22 January 1866, 3 April 1881 and 23 July 1949 produced tsunamis. The Chios-Cesme earthquake (1881, Mw 6.5 took place in the South of the Cesme strait while the Chios-Karaburun earthquake (1949, Mw 6.7 occurred in the North. The tsunamis caused by the earthquakes affected the coasts of Chios Island and Cesme. These waves are thought to be associated with the earthquakes and co-seismic underwater failures possibly occurred along the coasts of the Chios Island and Karaburun Peninsula or on the complex subaqueous morphology between these lands. Some sea waves or oscillations observed following the aftershocks are believed to be related to other natural phenomena; e.g. the seiches occurred mainly in open-narrow bays as triggered by the earthquakes.

  6. Evaluation of Seismic Rupture Models for the 2011 Tohoku-Oki Earthquake Using Tsunami Simulation

    Directory of Open Access Journals (Sweden)

    Ming-Da Chiou

    2013-01-01

    Full Text Available Developing a realistic, three-dimensional rupture model of the large offshore earthquake is difficult to accomplish directly through band-limited ground-motion observations. A potential indirect method is using a tsunami simulation to verify the rupture model in reverse because the initial conditions of the associated tsunamis are caused by a coseismic seafloor displacement correlating to the rupture pattern along the main faulting. In this study, five well-developed rupture models for the 2011 Tohoku-Oki earthquake were adopted to evaluate differences in simulated tsunamis and various rupture asperities. The leading wave of the simulated tsunamis triggered by the seafloor displacement in Yamazaki et al. (2011 model resulted in the smallest root-mean-squared difference (~0.082 m on average from the records of the eight DART (Deep-ocean Assessment and Reporting of Tsunamis stations. This indicates that the main seismic rupture during the 2011 Tohoku earthquake should occur in a large shallow slip in a narrow range adjacent to the Japan trench. This study also quantified the influences of ocean stratification and tides which are normally overlooked in tsunami simulations. The discrepancy between the simulations with and without stratification was less than 5% of the first peak wave height at the eight DART stations. The simulations, run with and without the presence of tides, resulted in a ~1% discrepancy in the height of the leading wave. Because simulations accounting for tides and stratification are time-consuming and their influences are negligible, particularly in the first tsunami wave, the two factors can be ignored in a tsunami prediction for practical purposes.

  7. Nowcasting Earthquakes and Tsunamis

    Science.gov (United States)

    Rundle, J. B.; Turcotte, D. L.

    2017-12-01

    . As another application, we can define large rectangular regions of subduction zones and shallow depths to compute the progress of the fault zone towards the next major tsunami-genic earthquake. We can then rank the relative progress of the major subduction zones of the world through their cycles of large earthquakes using this method to determine which zones are most at risk.

  8. THE POTENTIAL OF TSUNAMI GENERATION ALONG THE MAKRAN SUBDUCTION ZONE IN THE NORTHERN ARABIAN SEA. CASE STUDY: THE EARTHQUAKE AND TSUNAMI OF NOVEMBER 28, 1945

    Directory of Open Access Journals (Sweden)

    George Pararas-Carayannis

    2006-01-01

    Full Text Available Although large earthquakes along the Makran Subduction Zone are infrequent, the potential for the generation of destructive tsunamis in the Northern Arabian Sea cannot be overlooked. It is quite possible that historical tsunamis in this region have not been properly reported or documented. Such past tsunamis must have affected Southern Pakistan, India, Iran, Oman, the Maldives and other countries bordering the Indian Ocean.The best known of the historical tsunamis in the region is the one generated by the great earthquake of November 28, 1945 off Pakistan's Makran Coast (Balochistan in the Northern Arabian Sea. The destructive tsunami killed more than 4,000 people in Southern Pakistan but also caused great loss of life and devastation along the coasts of Western India, Iran, Oman and possibly elsewhere.The seismotectonics of the Makran subduction zone, historical earthquakes in the region, the recent earthquake of October 8, 2005 in Northern Pakistan, and the great tsunamigenic earthquakes of December 26, 2004 and March 28, 2005, are indicative of the active tectonic collision process that is taking place along the entire southern and southeastern boundary of the Eurasian plate as it collides with the Indian plate and adjacent microplates. Tectonic stress transference to other, stress loaded tectonic regions could trigger tsunamigenic earthquakes in the Northern Arabian Sea in the future.The northward movement and subduction of the Oman oceanic lithosphere beneath the Iranian micro-plate at a very shallow angle and at the high rate is responsible for active orogenesis and uplift that has created a belt of highly folded and densely faulted coastal mountain ridges along the coastal region of Makran, in both the Balochistan and Sindh provinces. The same tectonic collision process has created offshore thrust faults. As in the past, large destructive tsunamigenic earthquakes can occur along major faults in the east Makran region, near Karachi, as

  9. PRELIMINARY ANALYSIS OF THE EARTHQUAKE (MW 8.1 AND TSUNAMI OF APRIL 1, 2007, IN THE SOLOMON ISLANDS, SOUTHWESTERN PACIFIC OCEAN

    Directory of Open Access Journals (Sweden)

    Michael A. Fisher

    2007-01-01

    Full Text Available On April 1, 2007, a destructive earthquake (Mw 8.1 and tsunami struck the central Solomon Islands arc in the southwestern Pacific Ocean. The earthquake had a thrust-fault focal mechanism and occurred at shallow depth (between 15 km and 25 km beneath the island arc. The combined effects of the earthquake and tsunami caused dozens of fatalities and thousands remain without shelter. We present a preliminary analysis of the Mw-8.1 earthquake and resulting tsunami. Multichannel seismic- reflection data collected during 1984 show the geologic structure of the arc’s frontal prism within the earthquake’s rupture zone. Modeling tsunami-wave propagation indicates that some of the islands are so close to the earthquake epicenter that they were hard hit by tsunami waves as soon as 5 min. after shaking began, allowing people scant time to react.

  10. Impact of earthquake source complexity and land elevation data resolution on tsunami hazard assessment and fatality estimation

    Science.gov (United States)

    Muhammad, Ario; Goda, Katsuichiro

    2018-03-01

    This study investigates the impact of model complexity in source characterization and digital elevation model (DEM) resolution on the accuracy of tsunami hazard assessment and fatality estimation through a case study in Padang, Indonesia. Two types of earthquake source models, i.e. complex and uniform slip models, are adopted by considering three resolutions of DEMs, i.e. 150 m, 50 m, and 10 m. For each of the three grid resolutions, 300 complex source models are generated using new statistical prediction models of earthquake source parameters developed from extensive finite-fault models of past subduction earthquakes, whilst 100 uniform slip models are constructed with variable fault geometry without slip heterogeneity. The results highlight that significant changes to tsunami hazard and fatality estimates are observed with regard to earthquake source complexity and grid resolution. Coarse resolution (i.e. 150 m) leads to inaccurate tsunami hazard prediction and fatality estimation, whilst 50-m and 10-m resolutions produce similar results. However, velocity and momentum flux are sensitive to the grid resolution and hence, at least 10-m grid resolution needs to be implemented when considering flow-based parameters for tsunami hazard and risk assessments. In addition, the results indicate that the tsunami hazard parameters and fatality number are more sensitive to the complexity of earthquake source characterization than the grid resolution. Thus, the uniform models are not recommended for probabilistic tsunami hazard and risk assessments. Finally, the findings confirm that uncertainties of tsunami hazard level and fatality in terms of depth, velocity and momentum flux can be captured and visualized through the complex source modeling approach. From tsunami risk management perspectives, this indeed creates big data, which are useful for making effective and robust decisions.

  11. Sedimentary Signatures of Submarine Earthquakes: Deciphering the Extent of Sediment Remobilization from the 2011 Tohoku Earthquake and Tsunami and 2010 Haiti Earthquake

    Science.gov (United States)

    McHugh, C. M.; Seeber, L.; Moernaut, J.; Strasser, M.; Kanamatsu, T.; Ikehara, K.; Bopp, R.; Mustaque, S.; Usami, K.; Schwestermann, T.; Kioka, A.; Moore, L. M.

    2017-12-01

    The 2004 Sumatra-Andaman Mw9.3 and the 2011 Tohoku (Japan) Mw9.0 earthquakes and tsunamis were huge geological events with major societal consequences. Both were along subduction boundaries and ruptured portions of these boundaries that had been deemed incapable of such events. Submarine strike-slip earthquakes, such as the 2010 Mw7.0 in Haiti, are smaller but may be closer to population centers and can be similarly catastrophic. Both classes of earthquakes remobilize sediment and leave distinct signatures in the geologic record by a wide range of processes that depends on both environment and earthquake characteristics. Understanding them has the potential of greatly expanding the record of past earthquakes, which is critical for geohazard analysis. Recent events offer precious ground truth about the earthquakes and short-lived radioisotopes offer invaluable tools to identify sediments they remobilized. In the 2011 Mw9 Japan earthquake they document the spatial extent of remobilized sediment from water depths of 626m in the forearc slope to trench depths of 8000m. Subbottom profiles, multibeam bathymetry and 40 piston cores collected by the R/V Natsushima and R/V Sonne expeditions to the Japan Trench document multiple turbidites and high-density flows. Core tops enriched in xs210Pb,137Cs and 134Cs reveal sediment deposited by the 2011 Tohoku earthquake and tsunami. The thickest deposits (2m) were documented on a mid-slope terrace and trench (4000-8000m). Sediment was deposited on some terraces (600-3000m), but shed from the steep forearc slope (3000-4000m). The 2010 Haiti mainshock ruptured along the southern flank of Canal du Sud and triggered multiple nearshore sediment failures, generated turbidity currents and stirred fine sediment into suspension throughout this basin. A tsunami was modeled to stem from both sediment failures and tectonics. Remobilized sediment was tracked with short-lived radioisotopes from the nearshore, slope, in fault basins including the

  12. Tsunami Source Inversion Using Tide Gauge and DART Tsunami Waveforms of the 2017 Mw8.2 Mexico Earthquake

    Science.gov (United States)

    Adriano, Bruno; Fujii, Yushiro; Koshimura, Shunichi; Mas, Erick; Ruiz-Angulo, Angel; Estrada, Miguel

    2018-01-01

    On September 8, 2017 (UTC), a normal-fault earthquake occurred 87 km off the southeast coast of Mexico. This earthquake generated a tsunami that was recorded at coastal tide gauge and offshore buoy stations. First, we conducted a numerical tsunami simulation using a single-fault model to understand the tsunami characteristics near the rupture area, focusing on the nearby tide gauge stations. Second, the tsunami source of this event was estimated from inversion of tsunami waveforms recorded at six coastal stations and three buoys located in the deep ocean. Using the aftershock distribution within 1 day following the main shock, the fault plane orientation had a northeast dip direction (strike = 320°, dip = 77°, and rake =-92°). The results of the tsunami waveform inversion revealed that the fault area was 240 km × 90 km in size with most of the largest slip occurring on the middle and deepest segments of the fault. The maximum slip was 6.03 m from a 30 × 30 km2 segment that was 64.82 km deep at the center of the fault area. The estimated slip distribution showed that the main asperity was at the center of the fault area. The second asperity with an average slip of 5.5 m was found on the northwest-most segments. The estimated slip distribution yielded a seismic moment of 2.9 × 10^{21} Nm (Mw = 8.24), which was calculated assuming an average rigidity of 7× 10^{10} N/m2.

  13. Tsunami simulation method initiated from waveforms observed by ocean bottom pressure sensors for real-time tsunami forecast; Applied for 2011 Tohoku Tsunami

    Science.gov (United States)

    Tanioka, Yuichiro

    2017-04-01

    After tsunami disaster due to the 2011 Tohoku-oki great earthquake, improvement of the tsunami forecast has been an urgent issue in Japan. National Institute of Disaster Prevention is installing a cable network system of earthquake and tsunami observation (S-NET) at the ocean bottom along the Japan and Kurile trench. This cable system includes 125 pressure sensors (tsunami meters) which are separated by 30 km. Along the Nankai trough, JAMSTEC already installed and operated the cable network system of seismometers and pressure sensors (DONET and DONET2). Those systems are the most dense observation network systems on top of source areas of great underthrust earthquakes in the world. Real-time tsunami forecast has depended on estimation of earthquake parameters, such as epicenter, depth, and magnitude of earthquakes. Recently, tsunami forecast method has been developed using the estimation of tsunami source from tsunami waveforms observed at the ocean bottom pressure sensors. However, when we have many pressure sensors separated by 30km on top of the source area, we do not need to estimate the tsunami source or earthquake source to compute tsunami. Instead, we can initiate a tsunami simulation from those dense tsunami observed data. Observed tsunami height differences with a time interval at the ocean bottom pressure sensors separated by 30 km were used to estimate tsunami height distribution at a particular time. In our new method, tsunami numerical simulation was initiated from those estimated tsunami height distribution. In this paper, the above method is improved and applied for the tsunami generated by the 2011 Tohoku-oki great earthquake. Tsunami source model of the 2011 Tohoku-oki great earthquake estimated using observed tsunami waveforms, coseimic deformation observed by GPS and ocean bottom sensors by Gusman et al. (2012) is used in this study. The ocean surface deformation is computed from the source model and used as an initial condition of tsunami

  14. Indian Ocean Earthquake and Tsunami: Humanitarian Assistance and Relief Operations

    National Research Council Canada - National Science Library

    Margesson, Rhoda

    2005-01-01

    On December 26, 2004, a magnitude 9.0 undersea earthquake off the west coast of northern Sumatra, Indonesia, unleashed a tsunami that affected more than 12 countries throughout south and southeast Asia and stretched as far...

  15. Amplification of tsunami heights by delayed rupture of great earthquakes along the Nankai trough

    Science.gov (United States)

    Imai, K.; Satake, K.; Furumura, T.

    2010-04-01

    We investigated the effect of delayed rupture of great earthquakes along the Nankai trough on tsunami heights on the Japanese coast. As the tsunami source, we used a model of the 1707 Hoei earthquake, which consists of four segments: Tokai, Tonankai, and two Nankai segments. We first searched for the worst case, in terms of coastal tsunami heights, of rupture delay time on each segment, on the basis of superposition principle for the linear long wave theory. When the rupture starts on the Tonankai segment, followed by rupture on the Tokai segment 21 min later, as well as the eastern and western Nankai segments 15 and 28 min later, respectively, the average coastal tsunami height becomes the largest. To quantify the tsunami amplification, we compared the coastal tsunami heights from the delayed rupture with those from the simultaneous rupture model. Along the coasts of the sea of Hyu'uga and in the Bungo Channel, the tsunami heights become significantly amplified (>1.4 times larger) relative to the simultaneous rupture. Along the coasts of Tosa Bay and in the Kii Channel, the tsunami heights become amplified about 1.2 times. Along the coasts of the sea of Kumano and Ise Bay, and the western Enshu coast, the tsunami heights become slightly smaller for the delayed rupture. Along the eastern Enshu coast, the coast of Suruga Bay, and the west coast of Sagami Bay, the tsunami heights become amplified about 1.1 times.

  16. Predicting natural catastrophes tsunamis

    CERN Multimedia

    CERN. Geneva

    2005-01-01

    1. Tsunamis - Introduction - Definition of phenomenon - basic properties of the waves Propagation and dispersion Interaction with coasts - Geological and societal effects Origin of tsunamis - natural sources Scientific activities in connection with tsunamis. Ideas about simulations 2. Tsunami generation - The earthquake source - conventional theory The earthquake source - normal mode theory The landslide source Near-field observation - The Plafker index Far-field observation - Directivity 3. Tsunami warning - General ideas - History of efforts Mantle magnitudes and TREMOR algorithms The challenge of "tsunami earthquakes" Energy-moment ratios and slow earthquakes Implementation and the components of warning centers 4. Tsunami surveys - Principles and methodologies Fifteen years of field surveys and related milestones. Reconstructing historical tsunamis: eyewitnesses and geological evidence 5. Lessons from the 2004 Indonesian tsunami - Lessons in seismology Lessons in Geology The new technologies Lessons in civ...

  17. The El Asnam 1980 October 10 inland earthquake: a new hypothesis of tsunami generation

    Science.gov (United States)

    Roger, J.; Hébert, H.; Ruegg, J.-C.; Briole, P.

    2011-06-01

    The Western Mediterranean Sea is not considered as a high seismic region. Only several earthquakes with magnitude above five occur each year and only a handful have consequences on human beings and infrastructure. The El Asnam (Algeria) earthquake of 1980 October 10 with an estimated magnitude Ms= 7.3 is one of the most destructive earthquakes recorded in northern Africa and more largely in the Western Mediterranean Basin. Although it is located inland, it is known to have been followed by a small tsunami recorded on several tide gauges along the southeastern Spanish Coast. In 1954, a similar earthquake having occurred at the same location induced a turbidity current associated to a submarine landslide, which is widely known to have cut submarine phone cables far from the coast. This event was followed by a small tsunami attributed to the landslide. Thus the origin of the tsunami of 1980 was promptly attributed to the same kind of submarine slide. As no evidence of such mass movement was highlighted, and because the tsunami wave periods does not match with a landslide origin in both cases (1954 and 1980), this study considers two rupture scenarios, that the coseismic deformation itself (of about 10 cm off the Algerian coast near Ténès) is sufficient to produce a low amplitude (several centimetres) tsunami able to reach the Spanish southeastern coast from Alicante to Algeciras (Gibraltar strait to the west). After a discussion concerning the proposed rupture scenarios and their respective parameters, numerical tsunami modelling is performed on a set of bathymetric grids. Then the results of wave propagation and amplification (maximum wave height maps) are discussed, with a special attention to Alicante (Spain) Harbour where the location of two historical tide gauges allows the comparison between synthetic mareograms and historical records showing sufficient signal amplitude. This study is part of the active tsunami hazard assessment in Mediterranean Sea especially

  18. A Self-Consistent Fault Slip Model for the 2011 Tohoku Earthquake and Tsunami

    Science.gov (United States)

    Yamazaki, Yoshiki; Cheung, Kwok Fai; Lay, Thorne

    2018-02-01

    The unprecedented geophysical and hydrographic data sets from the 2011 Tohoku earthquake and tsunami have facilitated numerous modeling and inversion analyses for a wide range of dislocation models. Significant uncertainties remain in the slip distribution as well as the possible contribution of tsunami excitation from submarine slumping or anelastic wedge deformation. We seek a self-consistent model for the primary teleseismic and tsunami observations through an iterative approach that begins with downsampling of a finite fault model inverted from global seismic records. Direct adjustment of the fault displacement guided by high-resolution forward modeling of near-field tsunami waveform and runup measurements improves the features that are not satisfactorily accounted for by the seismic wave inversion. The results show acute sensitivity of the runup to impulsive tsunami waves generated by near-trench slip. The adjusted finite fault model is able to reproduce the DART records across the Pacific Ocean in forward modeling of the far-field tsunami as well as the global seismic records through a finer-scale subfault moment- and rake-constrained inversion, thereby validating its ability to account for the tsunami and teleseismic observations without requiring an exotic source. The upsampled final model gives reasonably good fits to onshore and offshore geodetic observations albeit early after-slip effects and wedge faulting that cannot be reliably accounted for. The large predicted slip of over 20 m at shallow depth extending northward to 39.7°N indicates extensive rerupture and reduced seismic hazard of the 1896 tsunami earthquake zone, as inferred to varying extents by several recent joint and tsunami-only inversions.

  19. Tsunami waves generated by dynamically triggered aftershocks of the 2010 Haiti earthquake

    Science.gov (United States)

    Ten Brink, U. S.; Wei, Y.; Fan, W.; Miller, N. C.; Granja, J. L.

    2017-12-01

    Dynamically-triggered aftershocks, thought to be set off by the passage of surface waves, are currently not considered in tsunami warnings, yet may produce enough seafloor deformation to generate tsunamis on their own, as judged from new findings about the January 12, 2010 Haiti earthquake tsunami in the Caribbean Sea. This tsunami followed the Mw7.0 Haiti mainshock, which resulted from a complex rupture along the north shore of Tiburon Peninsula, not beneath the Caribbean Sea. The mainshock, moreover, had a mixed strike-slip and thrust focal mechanism. There were no recorded aftershocks in the Caribbean Sea, only small coastal landslides and rock falls on the south shore of Tiburon Peninsula. Nevertheless, a tsunami was recorded on deep-sea DART buoy 42407 south of the Dominican Republic and on the Santo Domingo tide gauge, and run-ups of ≤3 m were observed along a 90-km-long stretch of the SE Haiti coast. Three dynamically-triggered aftershocks south of Haiti have been recently identified within the coda of the mainshock (stacks, and back-projecting the arrivals to the vicinity of the main shock (50-300 km). Two of the aftershocks, coming 20-40 s and 40-60 s after the mainshock, plot along NW-SE-trending submarine ridges in the Caribbean Sea south of Haiti. The third event, 120-140 s was located along the steep eastern slope of Bahoruco Peninsula, which is delineated by a normal fault. Forward tsunami models show that the arrival times of the DART buoy and tide gauge times are best fit by the earliest of the three aftershocks, with a Caribbean source 60 km SW of the mainshock rupture zone. Preliminary inversion of the DART buoy time series for fault locations and orientations confirms the location of the first source, but requires an additional unidentified source closer to shore 40 km SW of the mainshock rupture zone. This overall agreement between earthquake and tsunami analyses suggests that land-based earthquake ruptures and/or non-thrust main shocks can

  20. Physical Observations of the Tsunami during the September 8th 2017 Tehuantepec, Mexico Earthquake

    Science.gov (United States)

    Ramirez-Herrera, M. T.; Corona, N.; Ruiz-Angulo, A.; Melgar, D.; Zavala-Hidalgo, J.

    2017-12-01

    The September 8th 2017, Mw8.2 earthquake offshore Chiapas, Mexico, is the largest earthquake recorded history in Chiapas since 1902. It caused damage in the states of Oaxaca, Chiapas and Tabasco; it had more than 100 fatalities, over 1.5 million people were affected, and 41,000 homes were damaged in the state of Chiapas alone. This earthquake, a deep intraplate event on a normal fault on the oceanic subducting plate, generated a tsunami recorded at several tide gauge stations in Mexico and on the Pacific Ocean. Here we report the physical effects of the tsunami on the Chiapas coast and analyze the societal implications of this tsunami on the basis of our field observations. Tide gauge data indicate 11.3 and 8.2 cm of coastal subsidence at Salina Cruz and Puerto Chiapas stations. The associated tsunami waves were recorded first at Salina Cruz tide gauge station at 5:13 (GMT). We covered ground observations along 41 km of the coast of Chiapas, encompassing the sites with the highest projected wave heights based on the preliminary tsunami model (maximum tsunami amplitudes between -94.5 and -93.0 W). Runup and inundation distances were measured with an RTK GPS and using a Sokkia B40 level along 8 sites. We corrected runup data with estimated astronomical tide levels at the time of the tsunami. The tsunami occurred at low tide. The maximum runup was 3 m at Boca del Cielo, and maximum inundation distance was 190 m in Puerto Arista, corresponding to the coast directly opposite the epicenter and in the central sector of the Gulf of Tehuantepec. In general, our field data agree with the predicted results from the preliminary tsunami model. Tsunami scour and erosion was evident on the Chiapas coast. Tsunami deposits, mainly sand, reached up to 32 cm thickness thinning landwards up to 172 m distance. Even though the Mexican tsunami early warning system (CAT) issued several warnings, the tsunami arrival struck the Chiapas coast prior to the arrival of official warnings to the

  1. Evaluation of earthquake parameters used in the Indonesian Tsunami Early Warning System

    Science.gov (United States)

    Madlazim; Prastowo, Tjipto

    2016-02-01

    Twenty-two of a total of 30 earthquake events reported by the Indonesian Agency for Geophysics, Climatology and Meteorology during the time period 2007-2010 were falsely issued as tsunamigenic by the Indonesian Tsunami Early Warning System (Ina-TEWS). These 30 earthquakes were of different magnitudes and occurred in different locations. This study aimed to evaluate the performance of the Ina-TEWS using common earthquake parameters, including the earthquake magnitude, origin time, depth, and epicenter. In total, 298 datasets assessed by the Ina-TEWS and the global centroid moment tensor (CMT) method were assessed. The global CMT method is considered by almost all seismologists to be a reference for the determination of these parameters as they have been proved to be accurate. It was found that the earthquake magnitude, origin time, and depth provided by the Ina-TEWS were significantly different from those given in the global CMT catalog, whereas the latitude and longitude positions of the events provided by both tsunami assessment systems were coincident. The performance of the Ina-TEWS, particularly in terms of accuracy, remains questionable and needs to be improved.

  2. TSUNAMIS AND TSUNAMI-LIKE WAVES OF THE EASTERN UNITED STATES

    Directory of Open Access Journals (Sweden)

    James F. Lander

    2002-01-01

    Full Text Available The threat of tsunamis and tsunami-like waves hitting the eastern United States is very real despite a general impression to the contrary. We have cataloged 40 tsunamis and tsunami-like waves that have occurred in the eastern United States since 1600. Tsunamis were generated from such events as the 1755 Queen Anne’s earthquake, the Grand Banks event of 1929, the Charleston earthquake of 1886, and the New Madrid earthquakes of 1811-1812. The Queen Anne tsunami was observed as far away as St. Martin in the West Indies and is the only known teletsunami generated in this source region.Since subduction zones are absent around most of the Atlantic basin, tsunamis and tsunami-like waves along the United States East Coast are not generated from this traditional source, but appear, in most cases to be the result of slumping or landsliding associated with local earthquakes or with wave action associated with strong storms. Other sources of tsunamis and tsunami-like waves along the eastern seaboard have recently come to light including volcanic debris falls or catastrophic failure of volcanic slopes; explosive decompression of underwater methane deposits or oceanic meteor splashdowns. These sources are considered as well.

  3. Reconstruction of far-field tsunami amplitude distributions from earthquake sources

    Science.gov (United States)

    Geist, Eric L.; Parsons, Thomas E.

    2016-01-01

    The probability distribution of far-field tsunami amplitudes is explained in relation to the distribution of seismic moment at subduction zones. Tsunami amplitude distributions at tide gauge stations follow a similar functional form, well described by a tapered Pareto distribution that is parameterized by a power-law exponent and a corner amplitude. Distribution parameters are first established for eight tide gauge stations in the Pacific, using maximum likelihood estimation. A procedure is then developed to reconstruct the tsunami amplitude distribution that consists of four steps: (1) define the distribution of seismic moment at subduction zones; (2) establish a source-station scaling relation from regression analysis; (3) transform the seismic moment distribution to a tsunami amplitude distribution for each subduction zone; and (4) mix the transformed distribution for all subduction zones to an aggregate tsunami amplitude distribution specific to the tide gauge station. The tsunami amplitude distribution is adequately reconstructed for four tide gauge stations using globally constant seismic moment distribution parameters established in previous studies. In comparisons to empirical tsunami amplitude distributions from maximum likelihood estimation, the reconstructed distributions consistently exhibit higher corner amplitude values, implying that in most cases, the empirical catalogs are too short to include the largest amplitudes. Because the reconstructed distribution is based on a catalog of earthquakes that is much larger than the tsunami catalog, it is less susceptible to the effects of record-breaking events and more indicative of the actual distribution of tsunami amplitudes.

  4. Geological evidence of tsunamis and earthquakes at the Eastern Hellenic Arc: correlation with historical seismicity in the eastern Mediterranean Sea

    Directory of Open Access Journals (Sweden)

    Gerassimos Papadopoulos

    2012-12-01

    Full Text Available Sedimentary stratigraphy determined by trenching in Dalaman, south-western Turkey, revealed three sand layers at a distance of approximately 240 m from the shoreline and at elevations of +0.30, +0.55 and +0.90 cm. Storm surge action does not explain the features of these deposits that show instead typical characteristics of tsunami deposition. The sand layers correlate with historical tsunamis generated by large earthquakes which ruptured the eastern Hellenic Arc and Trench in 1303, 1481 and 1741. Accelerator mass spectrometry 14C dating of a wood sample from layer II indicated deposition in AD 1473±46, which fits the 1481 event. From an estimated average alluvium deposition rate of approximately 0.13 cm/year, layers I and III were dated at 1322 and 1724, which may represent the large 1303 and 1741 tsunamis. The geological record of the 1303 key event is very poor; therefore, sand layer I perhaps represents an important geological signature of the 1303 tsunami. However, the strong tsunami reported to have been generated by the 1609 earthquake is missing from Dalaman stratigraphy: this underlines the sensitivity of tsunami geological signatures to various local factors. The 1303 earthquake ruptured the trench between the islands of Crete and Rhodes. For the earthquakes of 1481, 1609 and 1741 we suggested that they were very likely generated in the Rhodes Abyssal Plain where sea depths of up to approximately 4200 m, together with the thrust component of seismotectonics, favor tsunami generation. Sand dykes directed upwards from layer I to layer II indicated that the 1481 earthquake triggered liquefaction of sand layer I. The results substantially widen our knowledge about the historical earthquake and tsunami activity in the eastern Mediterranean basin.

  5. Duration of Tsunami Generation Longer than Duration of Seismic Wave Generation in the 2011 Mw 9.0 Tohoku-Oki Earthquake

    Science.gov (United States)

    Fujihara, S.; Korenaga, M.; Kawaji, K.; Akiyama, S.

    2013-12-01

    We try to compare and evaluate the nature of tsunami generation and seismic wave generation in occurrence of the 2011 Tohoku-Oki earthquake (hereafter, called as TOH11), in terms of two type of moment rate functions, inferred from finite source imaging of tsunami waveforms and seismic waveforms. Since 1970's, the nature of "tsunami earthquakes" has been discussed in many researches (e.g. Kanamori, 1972; Kanamori and Kikuchi, 1993; Kikuchi and Kanamori, 1995; Ide et al., 1993; Satake, 1994) mostly based on analysis of seismic waveform data , in terms of the "slow" nature of tsunami earthquakes (e.g., the 1992 Nicaragura earthquake). Although TOH11 is not necessarily understood as a tsunami earthquake, TOH11 is one of historical earthquakes that simultaneously generated large seismic waves and tsunami. Also, TOH11 is one of earthquakes which was observed both by seismic observation network and tsunami observation network around the Japanese islands. Therefore, for the purpose of analyzing the nature of tsunami generation, we try to utilize tsunami waveform data as much as possible. In our previous studies of TOH11 (Fujihara et al., 2012a; Fujihara et al., 2012b), we inverted tsunami waveforms at GPS wave gauges of NOWPHAS to image the spatio-temporal slip distribution. The "temporal" nature of our tsunami source model is generally consistent with the other tsunami source models (e.g., Satake et al, 2013). For seismic waveform inversion based on 1-D structure, here we inverted broadband seismograms at GSN stations based on the teleseismic body-wave inversion scheme (Kikuchi and Kanamori, 2003). Also, for seismic waveform inversion considering the inhomogeneous internal structure, we inverted strong motion seismograms at K-NET and KiK-net stations, based on 3-D Green's functions (Fujihara et al., 2013a; Fujihara et al., 2013b). The gross "temporal" nature of our seismic source models are generally consistent with the other seismic source models (e.g., Yoshida et al

  6. Paleoseismic evidence of earthquakes and tsunamis along the southern part of the Japan Trench

    Science.gov (United States)

    Pilarczyk, Jessica; Sawai, Yuki; Horton, Ben; Namegaya, Yuichi; Shinozaki, Tetsuya; Tanigawa, Koichiro; Matsumoto, Dan; Dura, Tina; Fujiwara, Osamu; Shishikura, Masanobu

    2016-04-01

    The northern part of the Japan Trench has frequently generated tsunamigenic-earthquakes with magnitudes up to ~M 8.0. In contrast, the middle and southern parts of the Japan Trench were considered relatively inactive until the 2011 Tohoku (M 9.0) event generated one of the largest tsunamis in recorded history. Geologic evidence from the Sendai plain revealed an event in CE 869 that could have forecast the severity of the Tohoku tsunami in 2011. Seismic models indicate that the Tohoku earthquake may have transferred stress southwards down the fault to the potentially locked southern part of the Japan Trench. This transfer of stress towards a locked section of the trench could produce an earthquake in the near future that would be comparable in magnitude to the Tohoku event. Reconstructing the history of individual great earthquakes and accompanying tsunamis using geological records from the coastal zone adjacent to the southern part of the Japan Trench provides an assessment of the seismic hazard for metropolitan areas in east-central Japan. We have found two anomalous marine sand layers intercalated with muddy peat, which can be traced 3.8 km inland and 5.5 km along the present Kujukuri coastline, approximately 50 km east of Tokyo. Both sand layers have features consistent with tsunami deposits, such as a distinct erosional base, rip-up clasts, normal grading, a mud drape, and marine foraminifera. Results of radiocarbon dating constrain the age of the upper sand to 337 - 299 cal. yrs. BP, which likely corresponds to the only known southern Japan Trench rupture ever recorded, the Empo tsunami of CE 1677. The age of the lower sand is 979 - 903 cal. yrs. BP; marking an event for which there is no historical documentation at present. Preliminary tsunami simulation models indicate that a middle trench (Tohoku-style) rupture is not responsible for significant inundation of the Kujukuri coastline and would likely not have been capable of depositing either sand layer

  7. Survey Report on the Tsunami of the Michoacan, Mexico Earthquake of September 19, 1985

    OpenAIRE

    Abe, Katsuyuki; Hakuno, Motohiko; Takeuchi, Mikio; Katada, Toshiyuki

    1987-01-01

    The tsunami was caused by the Michoacan, Mexico earthquake (M. 8.1) of September 19, 1985. According to the site survey, sea water ran up to an elevation of 2 meters or more above sea level in the coastal areas of Mexico from Petatlan to Playa Azul. The tsunami was as high as 4 meters at Barra del Potosi and Playa Linda, where minor tsunami damages occurred; some thatched huts on the beaches were destroyed and pieces of furniture were swept out to sea. The tsunami magnitude Mt is estimated to...

  8. FIELD SURVEY REPORT OF TSUNAMI EFFECTS CAUSED BY THE AUGUST 2012 OFFSHORE EL SALAVADOR EARTHQUAKE

    Directory of Open Access Journals (Sweden)

    Francisco Gavidia-Medina

    2015-10-01

    Full Text Available This report describes the field survey of the western zone of El Salvador conducted by an international group of scientists and engineers following the earthquake and tsunami of 27 August 2012 (04:37 UTC, 26 August 10:37 pm local time. The earthquake generated a tsunami with a maximum height of ~ 6 m causing inundation of up to 300 m inland along a 40 km section of coastline in eastern El Salvador. * (Note: Presentation from the 6th International Tsunami Symposium of Tsunami Society International in Costa Rica in Sept. 2014 - based on the Field Survey Report of the tsunami effects caused by the August 2012 Earthquake which were compiled in a report by Jose C. Borrero of the University of California Tsunami Research Center. Contributors to that report and field survey participants included Hermann M. Fritz of the Georgia Institute of Technology, Francisco Gavidia-Medina, Jeniffer Larreynaga-Murcia, Rodolfo Torres-Cornejo, Manuel Diaz-Flores and Fabio Alvarad: of the Ministerio de Medio Ambiente y Recursos Naturales de El Salvador (MARN, Norwin Acosta: of the Instituto Nicaragüense de Estudios Territoriales( INOTER, Julie Leonard of the Office of Foreign Disaster Assistance (USAID, OFDA, Nic Arcos of the International Tsunami Information Center (ITIC and Diego Arcas of the Pacific Marine Environmental Laboratory (NOAA – PMEL The figures of this paper are from the report compiled by Jose C. Borrero and are numbered out of sequence out of sequence from the compiled joint report. The quality of figures 2.2, 2.3 and 2.4 is rather poor and the reader is referred to the original report, as shown in the references.

  9. Disaster mitigation science for Earthquakes and Tsunamis -For resilience society against natural disasters-

    Science.gov (United States)

    Kaneda, Y.; Takahashi, N.; Hori, T.; Kawaguchi, K.; Isouchi, C.; Fujisawa, K.

    2017-12-01

    Destructive natural disasters such as earthquakes and tsunamis have occurred frequently in the world. For instance, 2004 Sumatra Earthquake in Indonesia, 2008 Wenchuan Earthquake in China, 2010 Chile Earthquake and 2011 Tohoku Earthquake in Japan etc., these earthquakes generated very severe damages. For the reduction and mitigation of damages by destructive natural disasters, early detection of natural disasters and speedy and proper evacuations are indispensable. And hardware and software developments/preparations for reduction and mitigation of natural disasters are quite important. In Japan, DONET as the real time monitoring system on the ocean floor is developed and deployed around the Nankai trough seismogenic zone southwestern Japan. So, the early detection of earthquakes and tsunamis around the Nankai trough seismogenic zone will be expected by DONET. The integration of the real time data and advanced simulation researches will lead to reduce damages, however, in the resilience society, the resilience methods will be required after disasters. Actually, methods on restorations and revivals are necessary after natural disasters. We would like to propose natural disaster mitigation science for early detections, evacuations and restorations against destructive natural disasters. This means the resilience society. In natural disaster mitigation science, there are lots of research fields such as natural science, engineering, medical treatment, social science and literature/art etc. Especially, natural science, engineering and medical treatment are fundamental research fields for natural disaster mitigation, but social sciences such as sociology, geography and psychology etc. are very important research fields for restorations after natural disasters. Finally, to realize and progress disaster mitigation science, human resource cultivation is indispensable. We already carried out disaster mitigation science under `new disaster mitigation research project on Mega

  10. Investigating the March 28th 1875 and the September 20th 1920 earthquakes/tsunamis of the Southern Vanuatu arc, offshore Loyalty Islands, New Caledonia

    Science.gov (United States)

    Ioualalen, Mansour; Pelletier, Bernard; Solis Gordillo, Gabriela

    2017-07-01

    New Caledonia's Loyalty Islands are located in the southwest region of the Pacific ocean in the highly seismogenic southern Vanuatu subduction zone and therefore may be subject to devastating local tsunamis. Over the past 150 years, two large tsunamis were triggered by major earthquakes on March 28th 1875 and September 20th 1920. In this study, we use historical observations of these tsunamis (mostly in the form of testimonials), earthquake scenarios, and tsunami modeling to derive the magnitudes of these earthquakes, as well as tsunami runup and inundation maps. Assuming that these earthquakes were located on the interplate megathrust zone, the 1875 earthquake's magnitude was Mw8.1-8.2 and the 1920 event's magnitude was Mw7.5-7.8. The tsunami damage inflicted on the Lifou and Maré islands was approximately proportional to these magnitudes, with Maré being less impacted due to favorable wave directivity. Damage at Ouvéa island may have varied irregularly with the magnitude due to the effects of resonance. This study demonstrates that the quantitative characteristics of historical tsunamigenic earthquakes may be derived from qualitative estimates of tsunami runup.

  11. Proposal of methodology of tsunami accident sequence analysis induced by earthquake using DQFM methodology

    International Nuclear Information System (INIS)

    Muta, Hitoshi; Muramatsu, Ken

    2017-01-01

    Since the Fukushima-Daiichi nuclear power station accident, the Japanese regulatory body has improved and upgraded the regulation of nuclear power plants, and continuous effort is required to enhance risk management in the mid- to long term. Earthquakes and tsunamis are considered as the most important risks, and the establishment of probabilistic risk assessment (PRA) methodologies for these events is a major issue of current PRA. The Nuclear Regulation Authority (NRA) addressed the PRA methodology for tsunamis induced by earthquakes, which is one of the methodologies that should be enhanced step by step for the improvement and maturity of PRA techniques. The AESJ standard for the procedure of seismic PRA for nuclear power plants in 2015 provides the basic concept of the methodology; however, details of the application to the actual plant PRA model have not been sufficiently provided. This study proposes a detailed PRA methodology for tsunamis induced by earthquakes using the DQFM methodology, which contributes to improving the safety of nuclear power plants. Furthermore, this study also states the issues which need more research. (author)

  12. Tsunami geology in paleoseismology

    Science.gov (United States)

    Yuichi Nishimura,; Jaffe, Bruce E.

    2015-01-01

    The 2004 Indian Ocean and 2011 Tohoku-oki disasters dramatically demonstrated the destructiveness and deadliness of tsunamis. For the assessment of future risk posed by tsunamis it is necessary to understand past tsunami events. Recent work on tsunami deposits has provided new information on paleotsunami events, including their recurrence interval and the size of the tsunamis (e.g. [187–189]). Tsunamis are observed not only on the margin of oceans but also in lakes. The majority of tsunamis are generated by earthquakes, but other events that displace water such as landslides and volcanic eruptions can also generate tsunamis. These non-earthquake tsunamis occur less frequently than earthquake tsunamis; it is, therefore, very important to find and study geologic evidence for past eruption and submarine landslide triggered tsunami events, as their rare occurrence may lead to risks being underestimated. Geologic investigations of tsunamis have historically relied on earthquake geology. Geophysicists estimate the parameters of vertical coseismic displacement that tsunami modelers use as a tsunami's initial condition. The modelers then let the simulated tsunami run ashore. This approach suffers from the relationship between the earthquake and seafloor displacement, the pertinent parameter in tsunami generation, being equivocal. In recent years, geologic investigations of tsunamis have added sedimentology and micropaleontology, which focus on identifying and interpreting depositional and erosional features of tsunamis. For example, coastal sediment may contain deposits that provide important information on past tsunami events [190, 191]. In some cases, a tsunami is recorded by a single sand layer. Elsewhere, tsunami deposits can consist of complex layers of mud, sand, and boulders, containing abundant stratigraphic evidence for sediment reworking and redeposition. These onshore sediments are geologic evidence for tsunamis and are called ‘tsunami deposits’ (Figs. 26

  13. How Can Museum Exhibits Enhance Earthquake and Tsunami Hazard Resiliency?

    Science.gov (United States)

    Olds, S. E.

    2015-12-01

    Creating a natural disaster-ready community requires interoperating scientific, technical, and social systems. In addition to the technical elements that need to be in place, communities and individuals need to be prepared to react when a natural hazard event occurs. Natural hazard awareness and preparedness training and education often takes place through informal learning at science centers and formal k-12 education programs as well as through awareness raising via strategically placed informational tsunami warning signs and placards. Museums and science centers are influential in raising science literacy within a community, however can science centers enhance earthquake and tsunami resiliency by providing hazard science content and preparedness exhibits? Museum docents and informal educators are uniquely situated within the community. They are transmitters and translators of science information to broad audiences. Through interaction with the public, docents are well positioned to be informants of the knowledge beliefs, and feelings of science center visitors. They themselves are life-long learners, both constantly learning from the museum content around them and sharing this content with visitors. They are also members of a community where they live. In-depth interviews with museum informal educators and docents were conducted at a science center in coastal Pacific Northwest. This region has a potential to be struck by a great 9+ Mw earthquake and subsequent tsunami. During the interviews, docents described how they applied learning from natural hazard exhibits at a science visitor center to their daily lives. During the individual interviews, the museum docents described their awareness (knowledge, attitudes, and behaviors) of natural hazards where they live and work, the feelings evoked as they learned about their hazard vulnerability, the extent to which they applied this learning and awareness to their lives, such as creating an evacuation plan, whether

  14. Open-Ocean and Coastal Properties of Recent Major Tsunamis

    Science.gov (United States)

    Rabinovich, A.; Thomson, R.; Zaytsev, O.

    2017-12-01

    The properties of six major tsunamis during the period 2009-2015 (2009 Samoa; 2010 Chile; 2011 Tohoku; 2012 Haida Gwaii; 2014 and 2015 Chile) were thoroughly examined using coastal data from British Columbia, the U.S. West Coast and Mexico, and offshore open-ocean DART and NEPTUNE stations. Based on joint spectral analyses of the tsunamis and background noise, we have developed a method to suppress the influence of local topography and to use coastal observations to determine the underlying spectra of tsunami waves in the deep ocean. The "reconstructed" open-ocean tsunami spectra were found to be in close agreement with the actual tsunami spectra evaluated from the analysis of directly measured open-ocean tsunami records. We have further used the spectral estimates to parameterize tsunamis based on their integral open-ocean spectral characteristics. Three key parameters are introduced to describe individual tsunami events: (1) Integral open-ocean energy; (2) Amplification factor (increase of the mean coastal tsunami variance relative to the open-ocean variance); and (3) Tsunami colour, the frequency composition of the open-ocean tsunami waves. In particular, we found that the strongest tsunamis, associated with large source areas (the 2010 Chile and 2011 Tohoku) are "reddish" (indicating the dominance of low-frequency motions), while small-source events (the 2009 Samoa and 2012 Haida Gwaii) are "bluish" (indicating strong prevalence of high-frequency motions).

  15. Earthquake source parameters along the Hellenic subduction zone and numerical simulations of historical tsunamis in the Eastern Mediterranean

    Science.gov (United States)

    Yolsal-Çevikbilen, Seda; Taymaz, Tuncay

    2012-04-01

    We studied source mechanism parameters and slip distributions of earthquakes with Mw ≥ 5.0 occurred during 2000-2008 along the Hellenic subduction zone by using teleseismic P- and SH-waveform inversion methods. In addition, the major and well-known earthquake-induced Eastern Mediterranean tsunamis (e.g., 365, 1222, 1303, 1481, 1494, 1822 and 1948) were numerically simulated and several hypothetical tsunami scenarios were proposed to demonstrate the characteristics of tsunami waves, propagations and effects of coastal topography. The analogy of current plate boundaries, earthquake source mechanisms, various earthquake moment tensor catalogues and several empirical self-similarity equations, valid for global or local scales, were used to assume conceivable source parameters which constitute the initial and boundary conditions in simulations. Teleseismic inversion results showed that earthquakes along the Hellenic subduction zone can be classified into three major categories: [1] focal mechanisms of the earthquakes exhibiting E-W extension within the overriding Aegean plate; [2] earthquakes related to the African-Aegean convergence; and [3] focal mechanisms of earthquakes lying within the subducting African plate. Normal faulting mechanisms with left-lateral strike slip components were observed at the eastern part of the Hellenic subduction zone, and we suggest that they were probably concerned with the overriding Aegean plate. However, earthquakes involved in the convergence between the Aegean and the Eastern Mediterranean lithospheres indicated thrust faulting mechanisms with strike slip components, and they had shallow focal depths (h < 45 km). Deeper earthquakes mainly occurred in the subducting African plate, and they presented dominantly strike slip faulting mechanisms. Slip distributions on fault planes showed both complex and simple rupture propagations with respect to the variation of source mechanism and faulting geometry. We calculated low stress drop

  16. Identification of earthquakes that generate tsunamis in Java and Nusa Tenggara using rupture duration analysis

    Energy Technology Data Exchange (ETDEWEB)

    Pribadi, S., E-mail: sugengpribadimsc@gmail.com [Tsunami Warning Information Division, Indonesian Meteorological Climatological and Geophysical Agency (BMKG), Jalan Angkasa I No. 2, Jakarta13920 and Graduate Student of Earth Sciences, Faculty of Earth Sciences and Technology, Bandung Institute of T (Indonesia); Puspito, N. T.; Yudistira, T.; Afnimar,; Ibrahim, G. [Global Geophysics Research Group, Faculty of Mining and Petroleum Engineering, Bandung Institute of Technology (ITB), Jalan Ganesha 10, Bandung 40132 (Indonesia); Laksono, B. I. [Database Maintenance Division, Indonesian Meteorological Climatological and Geophysical Agency (BMKG), Jalan Angkasa I No.2, Jakarta 13920 (Indonesia); Adnan, Z. [Database Maintenance Division, Indonesian Meteorological Climatological and Geophysical Agency (BMKG), Jalan Angkasa I No. 2, Jakarta 13920 and Graduate Student of Earth Sciences, Faculty of Earth Sciences and Technology, Bandung Institute of Technol (Indonesia)

    2014-09-25

    Java and Nusa Tenggara are the tectonically active of Sunda arc. This study discuss the rupture duration as a manifestation of the power of earthquake-generated tsunami. We use the teleseismic (30° - 90°) body waves with high-frequency energy Seismometer is from IRIS network as amount 206 broadband units. We applied the Butterworth high bandpass (1 - 2 Hz) filtered. The arrival and travel times started from wave phase of P - PP which based on Jeffrey Bullens table with TauP program. The results are that the June 2, 1994 Banyuwangi and the July 17, 2006 Pangandaran earthquakes identified as tsunami earthquakes with long rupture duration (To > 100 second), medium magnitude (7.6 < Mw < 7.9) and located near the trench. The others are 4 tsunamigenic earthquakes and 3 inland earthquakes with short rupture duration start from To > 50 second which depend on its magnitude. Those events are located far from the trench.

  17. Probabilistic tsunami hazard assessment based on the long-term evaluation of subduction-zone earthquakes along the Sagami Trough, Japan

    Science.gov (United States)

    Hirata, K.; Fujiwara, H.; Nakamura, H.; Osada, M.; Ohsumi, T.; Morikawa, N.; Kawai, S.; Maeda, T.; Matsuyama, H.; Toyama, N.; Kito, T.; Murata, Y.; Saito, R.; Takayama, J.; Akiyama, S.; Korenaga, M.; Abe, Y.; Hashimoto, N.; Hakamata, T.

    2017-12-01

    For the forthcoming large earthquakes along the Sagami Trough where the Philippine Sea Plate is subducting beneath the northeast Japan arc, the Earthquake Research Committee(ERC) /Headquarters for Earthquake Research Promotion, Japanese government (2014a) assessed that M7 and M8 class earthquakes will occur there and defined the possible extent of the earthquake source areas. They assessed 70% and 0% 5% of the occurrence probability within the next 30 years (from Jan. 1, 2014), respectively, for the M7 and M8 class earthquakes. First, we set possible 10 earthquake source areas(ESAs) and 920 ESAs, respectively, for M8 and M7 class earthquakes. Next, we constructed 125 characterized earthquake fault models (CEFMs) and 938 CEFMs, respectively, for M8 and M7 class earthquakes, based on "tsunami receipt" of ERC (2017) (Kitoh et al., 2016, JpGU). All the CEFMs are allowed to have a large slip area for expression of fault slip heterogeneity. For all the CEFMs, we calculate tsunamis by solving a nonlinear long wave equation, using FDM, including runup calculation, over a nesting grid system with a minimum grid size of 50 meters. Finally, we re-distributed the occurrence probability to all CEFMs (Abe et al., 2014, JpGU) and gathered excess probabilities for variable tsunami heights, calculated from all the CEFMs, at every observation point along Pacific coast to get PTHA. We incorporated aleatory uncertainties inherent in tsunami calculation and earthquake fault slip heterogeneity. We considered two kinds of probabilistic hazard models; one is "Present-time hazard model" under an assumption that the earthquake occurrence basically follows a renewal process based on BPT distribution if the latest faulting time was known. The other is "Long-time averaged hazard model" under an assumption that earthquake occurrence follows a stationary Poisson process. We fixed our viewpoint, for example, on the probability that the tsunami height will exceed 3 meters at coastal points in next

  18. The Great 1787 Earthquake (M 8.6) and Tsunami along The Mexican Subduction Zone - History, Geology and Tsunami Hazard Assessment

    Science.gov (United States)

    Ramirez-Herrera, M. T.; Lagos, M.; Goguitchaichvili, A.; Machain-Castillo, M. L.; Caballero, M.; Ruiz-Fernandez, A. C.; Suarez, G.; Ortuño, M.

    2017-12-01

    The 1787 great earthquake (M 8.6) triggered a deadly tsunami that poured over the coast of Oaxaca, Guerrero, and Chiapas, along more than 500 km of the Mexican Pacific coast and up to 6 km inland. This tsunami, according with historical documents, destroyed mostly farmlands and livestock, and damaged few villages since the density of population was sparse at the time. We report first on geological evidence from the Corralero lagoon and adjacent coastal plain that seem in agreement with historical accounts. The deposit left by the 1787 tsunami can be traced along a transect of cores and test pits from the coastline and up to 1.6 km inland. The test pits showed an anomalous sand layer that was deposited in a single event in the swales of a series of beach ridges. The anomalous layer is almost continuous along the transect, about a 1000 m-long, and is formed of coarse to medium sand, at variable depths, with variable thickness, and pinching up with the distance from the coastline. We used stratigraphy, grain size, microfossils (foraminifera and diatoms), magnetic susceptibility and anisotropy of magnetic susceptibility proxies to reveal the nature of this anomalous sand layer. Stratigraphy, abrupt contacts, and magnetic properties support a sudden and rapid event, consisting of sands transported most probably by an extreme sea-wave far inland. Furthermore, based on the accounts of the 1787 earthquake (M 8.6) and tsunami, and estimates from 210Pb sedimentation rates, we suggest that this is the tsunami deposit left by the 1787 event. Tsunami modeling will further enhance the hazard and risk assessment of this area in Mexico.

  19. High-performance computing for structural mechanics and earthquake/tsunami engineering

    CERN Document Server

    Hori, Muneo; Ohsaki, Makoto

    2016-01-01

    Huge earthquakes and tsunamis have caused serious damage to important structures such as civil infrastructure elements, buildings and power plants around the globe.  To quantitatively evaluate such damage processes and to design effective prevention and mitigation measures, the latest high-performance computational mechanics technologies, which include telascale to petascale computers, can offer powerful tools. The phenomena covered in this book include seismic wave propagation in the crust and soil, seismic response of infrastructure elements such as tunnels considering soil-structure interactions, seismic response of high-rise buildings, seismic response of nuclear power plants, tsunami run-up over coastal towns and tsunami inundation considering fluid-structure interactions. The book provides all necessary information for addressing these phenomena, ranging from the fundamentals of high-performance computing for finite element methods, key algorithms of accurate dynamic structural analysis, fluid flows ...

  20. Excitation of tsunami by a pure strike-slip earthquake. ; Izu Oshima kinkai earthquake tsunami on Feb. 20, 1990. Yokozure danso jishin ni yoru tsunami no reiki. ; 1990 nen 2 gatsu 20 nichi Izu Oshima kinkai jishin tsunami

    Energy Technology Data Exchange (ETDEWEB)

    Abe, K. (Nippon Dental University, Tokyo (Japan). Niigata Junior College); Okada, M. (Meteorological Research Institute, Tsukuba (Japan))

    1993-06-24

    A numerical experiment was performed to reproduce the tsunami from the Izu-Oshima Kinkai Earthquake which occurred on February 20, 1990, using a tsunami excited by a pure strike-slip fault. An existence of a vertical fault with a length of 15 km and a width of 12 km was hypothesized in the south-north direction on the ocean bottom around the focal region. Then, a tsunami was assumed to have been excited when the fault was given a side-slip movement to create discrepancies of 1 m in the fault. Water level change for one hour after onset of the tsunami was calculated in one-second interval in each unit square with a side length of 1 km over an ocean area of 200 km from east to west and 150 km from north to south centering on the wave source. The results obtained from the calculation were harmonious with tsunami waveforms observed at five stations in the subject region and their spectral analytic results. Reproduced were the two predominant frequencies commonly observed at more than two stations, and difference in predominant cycles that appear according to azimuths of the observation points to the epicenter. These facts endorse the reasonability of the above hypothesis. 9 refs., 11 figs.

  1. Tsunami Research Status in IAEA after Fukushima Event

    International Nuclear Information System (INIS)

    Kim, Min Kyu; Choi, In Kil

    2012-01-01

    On March 11 th , 2011, a tremendous earthquake and tsunami occurred on the east coast of Japan. This 9.0 magnitude earthquake was the fifth greatest earthquake ever experienced on the planet. The most remarkable problem was that the Fukishima NPP sites. After Japan earthquake, many international researches about tsunami and earthquake event were started or revised. Especially, the most remarkable point of the great earthquake in east coast of Japan was tsunami event. Before this earthquake, the Niigata earthquake occurred in 2007 and the Kashiwazaki Kariwa nuclear power plant had little damaged. The research about the safety of nuclear power plant against earthquake events was activated by 2007 Niigata earthquake. However, the researches about a tsunami event were very few and only tsunami simulation was only focused. After the Fukushima accident, the international society became very interested in tsunami event as a major external event. Therefore in this study, the tsunami research status in IAEA after Fukushima event and the role of Korea are introduced

  2. Probabilistic Tsunami Hazard Analysis

    Science.gov (United States)

    Thio, H. K.; Ichinose, G. A.; Somerville, P. G.; Polet, J.

    2006-12-01

    The recent tsunami disaster caused by the 2004 Sumatra-Andaman earthquake has focused our attention to the hazard posed by large earthquakes that occur under water, in particular subduction zone earthquakes, and the tsunamis that they generate. Even though these kinds of events are rare, the very large loss of life and material destruction caused by this earthquake warrant a significant effort towards the mitigation of the tsunami hazard. For ground motion hazard, Probabilistic Seismic Hazard Analysis (PSHA) has become a standard practice in the evaluation and mitigation of seismic hazard to populations in particular with respect to structures, infrastructure and lifelines. Its ability to condense the complexities and variability of seismic activity into a manageable set of parameters greatly facilitates the design of effective seismic resistant buildings but also the planning of infrastructure projects. Probabilistic Tsunami Hazard Analysis (PTHA) achieves the same goal for hazards posed by tsunami. There are great advantages of implementing such a method to evaluate the total risk (seismic and tsunami) to coastal communities. The method that we have developed is based on the traditional PSHA and therefore completely consistent with standard seismic practice. Because of the strong dependence of tsunami wave heights on bathymetry, we use a full waveform tsunami waveform computation in lieu of attenuation relations that are common in PSHA. By pre-computing and storing the tsunami waveforms at points along the coast generated for sets of subfaults that comprise larger earthquake faults, we can efficiently synthesize tsunami waveforms for any slip distribution on those faults by summing the individual subfault tsunami waveforms (weighted by their slip). This efficiency make it feasible to use Green's function summation in lieu of attenuation relations to provide very accurate estimates of tsunami height for probabilistic calculations, where one typically computes

  3. Numerical tsunami simulations in the western Pacific Ocean and East China Sea from hypothetical M 9 earthquakes along the Nankai trough

    Science.gov (United States)

    Harada, Tomoya; Satake, Kenji; Furumura, Takashi

    2017-04-01

    We carried out tsunami numerical simulations in the western Pacific Ocean and East China Sea in order to examine the behavior of massive tsunami outside Japan from the hypothetical M 9 tsunami source models along the Nankai Trough proposed by the Cabinet Office of Japanese government (2012). The distribution of MTHs (maximum tsunami heights for 24 h after the earthquakes) on the east coast of China, the east coast of the Philippine Islands, and north coast of the New Guinea Island show peaks with approximately 1.0-1.7 m,4.0-7.0 m,4.0-5.0 m, respectively. They are significantly higher than that from the 1707 Ho'ei earthquake (M 8.7), the largest earthquake along the Nankai trough in recent Japanese history. Moreover, the MTH distributions vary with the location of the huge slip(s) in the tsunami source models although the three coasts are far from the Nankai trough. Huge slip(s) in the Nankai segment mainly contributes to the MTHs, while huge slip(s) or splay faulting in the Tokai segment hardly affects the MTHs. The tsunami source model was developed for responding to the unexpected occurrence of the 2011 Tohoku Earthquake, with 11 models along the Nanakai trough, and simulated MTHs along the Pacific coasts of the western Japan from these models exceed 10 m, with a maximum height of 34.4 m. Tsunami propagation was computed by the finite-difference method of the non-liner long-wave equations with the Corioli's force and bottom friction (Satake, 1995) in the area of 115-155 ° E and 8° S-40° N. Because water depth of the East China Sea is shallower than 200 m, the tsunami propagation is likely to be affected by the ocean bottom fiction. The 30 arc-seconds gridded bathymetry data provided by the General Bathymetric Chart of the Oceans (GEBCO-2014) are used. For long propagation of tsunami we simulated tsunamis for 24 hours after the earthquakes. This study was supported by the"New disaster mitigation research project on Mega thrust earthquakes around Nankai

  4. High resolution tsunami inversion for 2010 Chile earthquake

    Directory of Open Access Journals (Sweden)

    T.-R. Wu

    2011-12-01

    Full Text Available We investigate the feasibility of inverting high-resolution vertical seafloor displacement from tsunami waveforms. An inversion method named "SUTIM" (small unit tsunami inversion method is developed to meet this goal. In addition to utilizing the conventional least-square inversion, this paper also enhances the inversion resolution by Grid-Shifting method. A smooth constraint is adopted to gain stability. After a series of validation and performance tests, SUTIM is used to study the 2010 Chile earthquake. Based upon data quality and azimuthal distribution, we select tsunami waveforms from 6 GLOSS stations and 1 DART buoy record. In total, 157 sub-faults are utilized for the high-resolution inversion. The resolution reaches 10 sub-faults per wavelength. The result is compared with the distribution of the aftershocks and waveforms at each gauge location with very good agreement. The inversion result shows that the source profile features a non-uniform distribution of the seafloor displacement. The highly elevated vertical seafloor is mainly concentrated in two areas: one is located in the northern part of the epicentre, between 34° S and 36° S; the other is in the southern part, between 37° S and 38° S.

  5. High resolution tsunami inversion for 2010 Chile earthquake

    Science.gov (United States)

    Wu, T.-R.; Ho, T.-C.

    2011-12-01

    We investigate the feasibility of inverting high-resolution vertical seafloor displacement from tsunami waveforms. An inversion method named "SUTIM" (small unit tsunami inversion method) is developed to meet this goal. In addition to utilizing the conventional least-square inversion, this paper also enhances the inversion resolution by Grid-Shifting method. A smooth constraint is adopted to gain stability. After a series of validation and performance tests, SUTIM is used to study the 2010 Chile earthquake. Based upon data quality and azimuthal distribution, we select tsunami waveforms from 6 GLOSS stations and 1 DART buoy record. In total, 157 sub-faults are utilized for the high-resolution inversion. The resolution reaches 10 sub-faults per wavelength. The result is compared with the distribution of the aftershocks and waveforms at each gauge location with very good agreement. The inversion result shows that the source profile features a non-uniform distribution of the seafloor displacement. The highly elevated vertical seafloor is mainly concentrated in two areas: one is located in the northern part of the epicentre, between 34° S and 36° S; the other is in the southern part, between 37° S and 38° S.

  6. Identification of earthquakes that generate tsunamis in Java and Nusa Tenggara using rupture duration analysis

    International Nuclear Information System (INIS)

    Pribadi, S.; Puspito, N. T.; Yudistira, T.; Afnimar,; Ibrahim, G.; Laksono, B. I.; Adnan, Z.

    2014-01-01

    Java and Nusa Tenggara are the tectonically active of Sunda arc. This study discuss the rupture duration as a manifestation of the power of earthquake-generated tsunami. We use the teleseismic (30° - 90°) body waves with high-frequency energy Seismometer is from IRIS network as amount 206 broadband units. We applied the Butterworth high bandpass (1 - 2 Hz) filtered. The arrival and travel times started from wave phase of P - PP which based on Jeffrey Bullens table with TauP program. The results are that the June 2, 1994 Banyuwangi and the July 17, 2006 Pangandaran earthquakes identified as tsunami earthquakes with long rupture duration (To > 100 second), medium magnitude (7.6 50 second which depend on its magnitude. Those events are located far from the trench

  7. Earthquakes & Tsunamis flirting with the Ionosphere: the Sumatra gossip !!

    Science.gov (United States)

    Occhipinti, G.; Coïsson, P.; Rolland, L. M.; Lognonne, P.

    2009-12-01

    The December 26, 2004 Sumatra Earthquake and the related Indian Ocean Tsunami generated the largest remote sensing data-set observing natural hazards. The observations showed both, ground motion and ocean sea surface displacement, as well as the related strong ionospheric anomalies. Total electron content (TEC) perturbations have been observed on a global scale, using ground-based GPS receivers [DasGupta et al., 2006, Liu et al., 2006b] and dual-frequency altimeters (e.g., Jason-1 and Topex/Poseidon [Artru et al., 2005]); plasma velocity perturbation has been observed by Doppler soundings [Liu et al., 2006b, Occhipinti et al., 2009]. The observed perturbations may be characterized as two different waves: the first one is an atmospheric wave in the acoustic domain induced by propagation of Rayleigh waves on the Earth surface; the second one is a slower atmospheric wave in the gravity domain strongly coupled with the generated tsunami. Both waves are reproduced by our accurate modeling taking into account the earthquake/tsunami-neutral atmosphere coupling at the base of the atmosphere, as well as the neutral-plasma coupling in the overlying ionosphere [Occhipinti et al., 2006, 2006, 2009]. Here we present a review of the ionospheric observations related to the Sumatra event in the light of modeling to deeply investigate the coupling mechanism between Solid-Earth/Ocean/Atmosphere/Ionosphere. The matching between data and modeling opens new perspectives in the solid earth research as well as in the tsunami detection providing a new insight into the role of the remote sensing in the monitoring of natural hazard. [Artru et al., 2005] Geophys. J. Int., 160, 2005 [DasGupta et al., 2006] Earth Planet. Space, 35, 929-959. [Liu et al., 2006a] Geophys. Res. Lett., 33, L02103, 2006. [Liu et al., 2006b] J. Geophys. Res., 111, A05303. [Occhipinti et al., 2006] Geophys. Res. Lett., 33, L20104, 2006 [Occhipinti et al., 2008] Geophys. J. Int., 173, 3, 753-1135, 2008. [Occhipinti et

  8. The 1964 Great Alaska Earthquake and tsunamis: a modern perspective and enduring legacies

    Science.gov (United States)

    Brocher, Thomas M.; Filson, John R.; Fuis, Gary S.; Haeussler, Peter J.; Holzer, Thomas L.; Plafker, George; Blair, J. Luke

    2014-01-01

    The magnitude 9.2 Great Alaska Earthquake that struck south-central Alaska at 5:36 p.m. on Friday, March 27, 1964, is the largest recorded earthquake in U.S. history and the second-largest earthquake recorded with modern instruments. The earthquake was felt throughout most of mainland Alaska, as far west as Dutch Harbor in the Aleutian Islands some 480 miles away, and at Seattle, Washington, more than 1,200 miles to the southeast of the fault rupture, where the Space Needle swayed perceptibly. The earthquake caused rivers, lakes, and other waterways to slosh as far away as the coasts of Texas and Louisiana. Water-level recorders in 47 states—the entire Nation except for Connecticut, Delaware, and Rhode Island— registered the earthquake. It was so large that it caused the entire Earth to ring like a bell: vibrations that were among the first of their kind ever recorded by modern instruments. The Great Alaska Earthquake spawned thousands of lesser aftershocks and hundreds of damaging landslides, submarine slumps, and other ground failures. Alaska’s largest city, Anchorage, located west of the fault rupture, sustained heavy property damage. Tsunamis produced by the earthquake resulted in deaths and damage as far away as Oregon and California. Altogether the earthquake and subsequent tsunamis caused 129 fatalities and an estimated $2.3 billion in property losses (in 2013 dollars). Most of the population of Alaska and its major transportation routes, ports, and infrastructure lie near the eastern segment of the Aleutian Trench that ruptured in the 1964 earthquake. Although the Great Alaska Earthquake was tragic because of the loss of life and property, it provided a wealth of data about subductionzone earthquakes and the hazards they pose. The leap in scientific understanding that followed the 1964 earthquake has led to major breakthroughs in earth science research worldwide over the past half century. This fact sheet commemorates Great Alaska Earthquake and

  9. Radioactivity measurement of tsunami sediments due to the Great East Japan Earthquake in Miyagi prefecture

    International Nuclear Information System (INIS)

    Inoue, Chihiro; Joe, Seongjin

    2014-01-01

    The tsunami sediments and their directly under soils from 25 tsunami flooded areas in Miyagi prefecture after the Great East Japan Earthquake were analyzed quantitatively for radiocesium ( 134 Cs and 137 Cs) concentrations. It was found that the radiocesium released in the reactor accidents of the Fukushima Daiichi Nuclear Power Plant stayed for at least 6 months in the tsunami sediments layer of a few centimeter thickness. On the other hand, from the results of the radiocesium extraction test using the tsunami sediments and 3 kinds of inorganic solvents, it was also found that the radiocesium in the tsunami sediments passed ca. 6 months after fall was hardly eluted with rain water (pH 5.6 ∼ 7.0) and combined strongly with clay minerals in the tsunami sediments. (K. Kato)

  10. Simulation of a Dispersive Tsunami due to the 2016 El Salvador-Nicaragua Outer-Rise Earthquake (M w 6.9)

    Science.gov (United States)

    Tanioka, Yuichiro; Ramirez, Amilcar Geovanny Cabrera; Yamanaka, Yusuke

    2018-01-01

    The 2016 El Salvador-Nicaragua outer-rise earthquake (M w 6.9) generated a small tsunami observed at the ocean bottom pressure sensor, DART 32411, in the Pacific Ocean off Central America. The dispersive observed tsunami is well simulated using the linear Boussinesq equations. From the dispersive character of tsunami waveform, the fault length and width of the outer-rise event is estimated to be 30 and 15 km, respectively. The estimated seismic moment of 3.16 × 1019 Nm is the same as the estimation in the Global CMT catalog. The dispersive character of the tsunami in the deep ocean caused by the 2016 outer-rise El Salvador-Nicaragua earthquake could constrain the fault size and the slip amount or the seismic moment of the event.

  11. Simulation of a Dispersive Tsunami due to the 2016 El Salvador-Nicaragua Outer-Rise Earthquake ( M w 6.9)

    Science.gov (United States)

    Tanioka, Yuichiro; Ramirez, Amilcar Geovanny Cabrera; Yamanaka, Yusuke

    2018-04-01

    The 2016 El Salvador-Nicaragua outer-rise earthquake ( M w 6.9) generated a small tsunami observed at the ocean bottom pressure sensor, DART 32411, in the Pacific Ocean off Central America. The dispersive observed tsunami is well simulated using the linear Boussinesq equations. From the dispersive character of tsunami waveform, the fault length and width of the outer-rise event is estimated to be 30 and 15 km, respectively. The estimated seismic moment of 3.16 × 1019 Nm is the same as the estimation in the Global CMT catalog. The dispersive character of the tsunami in the deep ocean caused by the 2016 outer-rise El Salvador-Nicaragua earthquake could constrain the fault size and the slip amount or the seismic moment of the event.

  12. Tohoku-Oki Earthquake Tsunami Runup and Inundation Data for Sites Around the Island of Hawaiʻi

    Science.gov (United States)

    Trusdell, Frank A.; Chadderton, Amy; Hinchliffe, Graham; Hara, Andrew; Patenge, Brent; Weber, Tom

    2012-01-01

    At 0546 U.t.c. March 11, 2011, a Mw 9.0 ("great") earthquake occurred near the northeast coast of Honshu Island, Japan, generating a large tsunami that devastated the east coast of Japan and impacted many far-flung coastal sites around the Pacific Basin. After the earthquake, the Pacific Tsunami Warning Center issued a tsunami alert for the State of Hawaii, followed by a tsunami-warning notice from the local State Civil Defense on March 10, 2011 (Japan is 19 hours ahead of Hawaii). After the waves passed the islands, U.S. Geological Survey (USGS) scientists from the Hawaiian Volcano Observatory (HVO) measured inundation (maximum inland distance of flooding), runup (elevation at maximum extent of inundation) and took photographs in coastal areas around the Island of Hawaiʻi. Although the damage in West Hawaiʻi is well documented, HVO's mapping revealed that East Hawaiʻi coastlines were also impacted by the tsunami. The intent of this report is to provide runup and inundation data for sites around the Island of Hawaiʻi.

  13. Appraising the Early-est earthquake monitoring system for tsunami alerting at the Italian Candidate Tsunami Service Provider

    Science.gov (United States)

    Bernardi, F.; Lomax, A.; Michelini, A.; Lauciani, V.; Piatanesi, A.; Lorito, S.

    2015-09-01

    In this paper we present and discuss the performance of the procedure for earthquake location and characterization implemented in the Italian Candidate Tsunami Service Provider at the Istituto Nazionale di Geofisica e Vulcanologia (INGV) in Rome. Following the ICG/NEAMTWS guidelines, the first tsunami warning messages are based only on seismic information, i.e., epicenter location, hypocenter depth, and magnitude, which are automatically computed by the software Early-est. Early-est is a package for rapid location and seismic/tsunamigenic characterization of earthquakes. The Early-est software package operates using offline-event or continuous-real-time seismic waveform data to perform trace processing and picking, and, at a regular report interval, phase association, event detection, hypocenter location, and event characterization. Early-est also provides mb, Mwp, and Mwpd magnitude estimations. mb magnitudes are preferred for events with Mwp ≲ 5.8, while Mwpd estimations are valid for events with Mwp ≳ 7.2. In this paper we present the earthquake parameters computed by Early-est between the beginning of March 2012 and the end of December 2014 on a global scale for events with magnitude M ≥ 5.5, and we also present the detection timeline. We compare the earthquake parameters automatically computed by Early-est with the same parameters listed in reference catalogs. Such reference catalogs are manually revised/verified by scientists. The goal of this work is to test the accuracy and reliability of the fully automatic locations provided by Early-est. In our analysis, the epicenter location, hypocenter depth and magnitude parameters do not differ significantly from the values in the reference catalogs. Both mb and Mwp magnitudes show differences to the reference catalogs. We thus derived correction functions in order to minimize the differences and correct biases between our values and the ones from the reference catalogs. Correction of the Mwp

  14. A Hybrid Tsunami Risk Model for Japan

    Science.gov (United States)

    Haseemkunju, A. V.; Smith, D. F.; Khater, M.; Khemici, O.; Betov, B.; Scott, J.

    2014-12-01

    Around the margins of the Pacific Ocean, denser oceanic plates slipping under continental plates cause subduction earthquakes generating large tsunami waves. The subducting Pacific and Philippine Sea plates create damaging interplate earthquakes followed by huge tsunami waves. It was a rupture of the Japan Trench subduction zone (JTSZ) and the resultant M9.0 Tohoku-Oki earthquake that caused the unprecedented tsunami along the Pacific coast of Japan on March 11, 2011. EQECAT's Japan Earthquake model is a fully probabilistic model which includes a seismo-tectonic model describing the geometries, magnitudes, and frequencies of all potential earthquake events; a ground motion model; and a tsunami model. Within the much larger set of all modeled earthquake events, fault rupture parameters for about 24000 stochastic and 25 historical tsunamigenic earthquake events are defined to simulate tsunami footprints using the numerical tsunami model COMCOT. A hybrid approach using COMCOT simulated tsunami waves is used to generate inundation footprints, including the impact of tides and flood defenses. Modeled tsunami waves of major historical events are validated against observed data. Modeled tsunami flood depths on 30 m grids together with tsunami vulnerability and financial models are then used to estimate insured loss in Japan from the 2011 tsunami. The primary direct report of damage from the 2011 tsunami is in terms of the number of buildings damaged by municipality in the tsunami affected area. Modeled loss in Japan from the 2011 tsunami is proportional to the number of buildings damaged. A 1000-year return period map of tsunami waves shows high hazard along the west coast of southern Honshu, on the Pacific coast of Shikoku, and on the east coast of Kyushu, primarily associated with major earthquake events on the Nankai Trough subduction zone (NTSZ). The highest tsunami hazard of more than 20m is seen on the Sanriku coast in northern Honshu, associated with the JTSZ.

  15. Near field earthquake sources scenarios and related tsunamis on the French-Italian Riviera (Western Mediterranean

    Science.gov (United States)

    Larroque, Christophe; Ioualalen, Mansour; Scotti, Oona

    2014-05-01

    The large system of thrust faults recently evidenced at the foot of the northern Ligurian margin accommodates the inversion of this ancient passive margin since at least 5 Ma (Messinian times). At depth, these faults are certainly connected to a major northward dipping thrust that accounts for the major part of the seismicity in the northern Ligurian Sea. The deformations of the Quaternary sediments along the faults attest to a compressive tectonic regime consistent with the focal mechanisms of earthquakes. The major event in the area (the Ligurian earthquake, 1887/02/23, Mw 6.7-6.9 and the related tsunami) could result from the activation of part of the Ligurian thrust. Starting from the Ligurian earthquake source characteristics (strike: N55°E, dip: 16°N, length: 35 km, width: 17 km, co-seismic slip: 1.5 m, focal depth: 15 km, Mw 6.9), we have built an exhaustive set of earthquake scenarios involving the 80 km long Ligurian thrust. (1) Two of these earthquake scenarios ruptured respectively the eastern (offshore Imperia) and western (offshore Nice) part of the Ligurian thrust. (2) As these scenarios must scan the range of potential events in accordance with the geology, a second group of scenarios tests an 80 km long rupture of the entire Ligurian thrust with different strikes (N55°E and N70°E) and different widths of the faulting surface (17 km and 27 km) and then co-seismic slips of 2 m and 3.3 m, respectively. As the Ligurian coast is a densely populated and industrial area, the vulnerability is high. We want to stress here that we are more concerned with tsunamis triggered by local earthquakes. This is because, considering their arrival times (a few minutes), the risk prevention cannot be handled by existing tsunami warning system. For all scenarios we evaluate the tsunami coastal impact. The spatial distribution of the maximum wave height (MWH) is provided with a tentative identification of the processes that are responsible for it. The predictions

  16. Significant Tsunami Events

    Science.gov (United States)

    Dunbar, P. K.; Furtney, M.; McLean, S. J.; Sweeney, A. D.

    2014-12-01

    Tsunamis have inflicted death and destruction on the coastlines of the world throughout history. The occurrence of tsunamis and the resulting effects have been collected and studied as far back as the second millennium B.C. The knowledge gained from cataloging and examining these events has led to significant changes in our understanding of tsunamis, tsunami sources, and methods to mitigate the effects of tsunamis. The most significant, not surprisingly, are often the most devastating, such as the 2011 Tohoku, Japan earthquake and tsunami. The goal of this poster is to give a brief overview of the occurrence of tsunamis and then focus specifically on several significant tsunamis. There are various criteria to determine the most significant tsunamis: the number of deaths, amount of damage, maximum runup height, had a major impact on tsunami science or policy, etc. As a result, descriptions will include some of the most costly (2011 Tohoku, Japan), the most deadly (2004 Sumatra, 1883 Krakatau), and the highest runup ever observed (1958 Lituya Bay, Alaska). The discovery of the Cascadia subduction zone as the source of the 1700 Japanese "Orphan" tsunami and a future tsunami threat to the U.S. northwest coast, contributed to the decision to form the U.S. National Tsunami Hazard Mitigation Program. The great Lisbon earthquake of 1755 marked the beginning of the modern era of seismology. Knowledge gained from the 1964 Alaska earthquake and tsunami helped confirm the theory of plate tectonics. The 1946 Alaska, 1952 Kuril Islands, 1960 Chile, 1964 Alaska, and the 2004 Banda Aceh, tsunamis all resulted in warning centers or systems being established.The data descriptions on this poster were extracted from NOAA's National Geophysical Data Center (NGDC) global historical tsunami database. Additional information about these tsunamis, as well as water level data can be found by accessing the NGDC website www.ngdc.noaa.gov/hazard/

  17. Holocene Tsunami Deposits From Large Tsunamis Along the Kuril Subduction Zone, Northeast Japan

    Science.gov (United States)

    Nanayama, F.; Furukawa, R.; Satake, K.; Soeda, Y.; Shigeno, K.

    2003-12-01

    Holocene tsunami deposits in eastern Hokkaido between Nemuro and Tokachi show that the Kuril subduction zone repeatedly produced earthquakes and tsunamis larger than those recorded in this region since AD 1804 (Nanayama et al., Nature, 424, 660-663, 2003). Twenty-two postulated tsunami sand layers from the past 9500 years are preserved on lake bottom near Kushiro City, and about ten postulated tsunami sand layers from the past 3000 years are preserved in peat layers on the coastal marsh of Kiritappu. We dated these ten tsunami deposits (named Ts1 to Ts10 from shallower to deeper) in peat layers by radiocarbon and tephrochronology, correlated them with historical earthquakes and tsunamis, and surveyed their spatial distribution to estimate the tsunamisO inland inundation limits. Ts10 and Ts9 are under regional tephra Ta-c2 (ca. 2.5 ka) and represent prehistorical events. Ts8 to Ts5 are between two regional tephra layers Ta-c2 and B-Tm (ca. 9th century). In particular, Ts5 is found just below B-Tm, so it is dated 9th century (Heian era). Ts4 is dated ca 13th century (Kamakura era), while Ts3, found just below Us-b and Ta-b (AD 1667-1663), is dated 17th century (Edo era). Ts2 is dated 19th century (Edo era) and may correspond to the AD 1843 Tempo Tokachi-oki earthquake (Mt 8.0) recorded in a historical document Nikkanki of Kokutai-ji temple at Akkeshi. Ts1 is inferred 20th century and may correspond to the tsunami from the AD 1960 Chilean earthquake (M 9.5) or the AD 1952 Tokachi-oki earthquake (Mt 8.2). Our detailed surveys indicate that Ts3 and Ts4 can be traced more than 3 km from the present coast line in Kirittapu marsh, much longer than the limits (< 1 km) of recent deposits Ts1 and Ts2 or documented inundation of the 19th and 20th century tsunamis. The recurrence intervals of great tsunami inundation are about 400 to 500 years, longer than that of typical interplate earthquakes along the Kuril subduction zone. The longer interval and the apparent large tsunami

  18. Geoethics and decision science issues in Japan's disaster management system: case study in the 2011 Tohoku earthquake and tsunami

    Science.gov (United States)

    Sugimoto, Megumi

    2015-04-01

    The March 11, 2011 Tohoku earthquake and its tsunami killed 18,508 people, including the missing (National Police Agency report as of April 2014) and raise the Level 7 accident at TEPCO's Fukushima Dai-ichi nuclear power station in Japan. The problems revealed can be viewed as due to a combination of risk-management, risk-communication, and geoethics issues. Japan's preparations for earthquakes and tsunamis are based on the magnitude of the anticipated earthquake for each region. The government organization coordinating the estimation of anticipated earthquakes is the "Headquarters for Earthquake Research Promotion" (HERP), which is under the Ministry of Education, Culture, Sports, Science and Technology (MEXT). Japan's disaster mitigation system is depicted schematically as consisting of three layers: seismology, civil engineering, and disaster mitigation planning. This research explains students in geoscience should study geoethics as part of their education related Tohoku earthquake and the Level 7 accident at TEPCO's Fukushima Dai-ichi nuclear power station. Only when they become practicing professionals, they will be faced with real geoethical dilemmas. A crisis such as the 2011 earthquake, tsunami, and Fukushima Dai-ichi nuclear accident, will force many geoscientists to suddenly confront previously unanticipated geoethics and risk-communication issues. One hopes that previous training will help them to make appropriate decisions under stress. We name it "decision science".

  19. Numerical modelling and evacuation strategies for tsunami awareness: lessons from the 2012 Haida Gwaii Tsunami

    OpenAIRE

    Santos, Angela; Tavares, Alexandre Oliveira; Queirós, Margarida

    2016-01-01

    On October 28, 2012, an earthquake occurred offshore Canada, with a magnitude Mw of 7.8, triggering a tsunami that propagated through the Pacific Ocean. The tsunami numerical model results show it would not be expected to generate widespread inundation on Hawaii. Yet, two hours after the earthquake, the Pacific Tsunami Warning Centre (PTWC) issued a tsunami warning to the state of Hawaii. Since the state was hit by several tsunamis in the past, regular siren exercises, tsuna...

  20. Two Cases of Tsunami Dust Pneumonia: Organizing Pneumonia Caused by the Inhalation of Dried Tsunami Sludge after the 2011 Great East Japan Earthquake

    Science.gov (United States)

    Yamanda, Shinsuke; Kobayashi, Seiichi; Hanagama, Masakazu; Sato, Hikari; Suzuki, Satoshi; Ueda, Shinsaku; Takahashi, Toru; Yanai, Masaru

    2016-01-01

    We report two cases of organizing pneumonia (OP) secondary to the inhalation of the dried tsunami sludge which formed during the 2011 Great East Japan Earthquake and the consequent tsunami. After the disaster, both of these patients had been engaged in the restoration work. About half a month later, they developed shortness of breath and pulmonary infiltrates. These patients were diagnosed with interstitial pneumonia. Their biopsy specimens revealed multifocal peribronchiolitis and OP. An electron probe microanalysis of these specimens demonstrated the presence of elements from the earth's crust in the inflammatory lesions. These two cases indicate that exposure to dried tsunami sludge can cause OP. PMID:27980267

  1. Five centuries of tsunamis and land-level changes in the overlapping rupture area of the 1960 and 2010 Chilean earthquakes

    Science.gov (United States)

    Ely, Lisa L.; Cisternas, Marco; Wesson, Robert L.; Dura, Tina

    2014-01-01

    A combination of geological and historical records from south-central Chile provides a means to address general questions about the stability of megathrust rupture patches and the range of variation expected among earthquakes and tsunamis along a particular stretch of a subduction zone. The Tirúa River estuary (38.3°S) records four large tsunamis and coseismic land-level changes over the past 450 years within the overlapping rupture zones of the great subduction-zone earthquakes of A.D. 1960 (Mw9.5) and 2010 (Mw 8.8). Sand layers 2 km up the Tirúa River represent the 2010 and 1960 tsunamis and two historical tsunamis, most likely in A.D. 1751 and 1575. Differing land-level changes during these earthquakes likely denote differences in the spatial distribution of slip on the megathrust in both the strike and dip directions within the overlapping rupture zone, with the uplift at Tirúa in 1751 and 2010 probably caused by slip extending farther landward and to greater depth than in 1575 and 1960, which showed subsidence or little change.

  2. Mediterranean megaturbidite triggered by the AD 365 Crete earthquake and tsunami

    Science.gov (United States)

    Polonia, Alina; Bonatti, Enrico; Camerlenghi, Angelo; Lucchi, Renata Giulia; Panieri, Giuliana; Gasperini, Luca

    2013-01-01

    Historian Ammianus Marcellinus documented the devastating effects of a tsunami hitting Alexandria, Egypt, on July 21, AD 365. "The solidity of the earth was made to shake … and the sea was driven away. The waters returning when least expected killed many thousands by drowning. Huge ships… perched on the roofs of houses… hurled miles from the shore….”. Other settlements around the Mediterranean were hit at roughly the same time. This scenario is similar to that of the recent Sumatra and Tohoku tsunamis. Based on geophysical surveys and sediment cores from the Ionian Sea we show that the 20–25 m thick megaturbidite known in the literature as Homogenite/Augias was triggered not by the Santorini caldera collapse but by the 365 AD Cretan earthquake/tsunami. An older similar megaturbidite was deposited after 14.590 ± 80 yr BP, implying a large recurrence time of such extreme sedimentary events in the Mediterranean Sea. PMID:23412517

  3. Report by the 'Mega-earthquakes and mega-tsunamis' subgroup; Rapport du sous-groupe Sismique 'Megaseismes et megatsunamis'

    Energy Technology Data Exchange (ETDEWEB)

    Friedel, Jacques; Courtillot, Vincent; Dercourt, Jean; Jaupart, Claude; Le Pichon, Xavier; Poirier, Jean-Paul; Salencon, Jean; Tapponnier, Paul; Dautray, Robert; Carpentier, Alain; Taquet, Philippe; Blanchet, Rene; Le Mouel, Jean-Louis [Academie des sciences, 23, quai de Conti, 75006 Paris (France); BARD, Pierre-Yves [Observatoire des sciences de l' Univers de l' universite de Grenoble - OSUG, Universite Joseph Fourier, BP 53, 38041 Grenoble Cedex 9 (France); Bernard, Pascal; Montagner, Jean-Paul; Armijo, Rolando; Shapiro, Nikolai; Tait, Steve [Institut de physique du globe de Paris, 1, rue Jussieu - 75238 Paris cedex 05 (France); Cara, Michel [Ecole et Observatoire des sciences de la Terre de l' universite de Strasbourg - EOST, F-67084 Strasbourg cedex (France); Madariaga, Raul [Ecole normale superieure, 45, rue d' Ulm / 29, rue d' Ulm, F-75230 Paris cedex 05 (France); Pecker, Alain [Academie des technologies, Grand Palais des Champs Elysees - Porte C - Avenue Franklin D. Roosevelt - 75008 Paris (France); Schindele, Francois [CEA/DAM, DIF/DASE/SLDG, 91297 ARPAJON Cedex (France); Douglas, John [BRGM, 3 avenue Claude-Guillemin - BP 36009 - 45060 Orleans Cedex 2 (France)

    2011-06-15

    This report comprises a presentation of scientific data on subduction earthquakes, on tsunamis and on the Tohoku earthquake. It proposes a detailed description of the French situation (in the West Indies, in metropolitan France, and in terms of soil response), and a discussion of social and economic issues (governance, seismic regulation and nuclear safety, para-seismic protection of constructions). The report is completed by other large documents: presentation of data on the Japanese earthquake, discussion on prediction and governance errors in the management of earthquake mitigation in Japan, discussions on tsunami prevention, on needs of research on accelerometers, and on the seismic risk in France

  4. An Earthquake Source Sensitivity Analysis for Tsunami Propagation in the Eastern Mediterranean

    Science.gov (United States)

    Necmioglu, Ocal; Meral Ozel, Nurcan

    2013-04-01

    An earthquake source parameter sensitivity analysis for tsunami propagation in the Eastern Mediterranean has been performed based on 8 August 1303 Crete and Dodecanese Islands earthquake resulting in destructive inundation in the Eastern Mediterranean. The analysis involves 23 cases describing different sets of strike, dip, rake and focal depth, while keeping the fault area and displacement, thus the magnitude, same. The main conclusions of the evaluation are drawn from the investigation of the wave height distributions at Tsunami Forecast Points (TFP). The earthquake vs. initial tsunami source parameters comparison indicated that the maximum initial wave height values correspond in general to the changes in rake angle. No clear depth dependency is observed within the depth range considered and no strike angle dependency is observed in terms of amplitude change. Directivity sensitivity analysis indicated that for the same strike and dip, 180° shift in rake may lead to 20% change in the calculated tsunami wave height. Moreover, an approximately 10 min difference in the arrival time of the initial wave has been observed. These differences are, however, greatly reduced in the far field. The dip sensitivity analysis, performed separately for thrust and normal faulting, has both indicated that an increase in the dip angle results in the decrease of the tsunami wave amplitude in the near field approximately 40%. While a positive phase shift is observed, the period and the shape of the initial wave stays nearly the same for all dip angles at respective TFPs. These affects are, however, not observed at the far field. The resolution of the bathymetry, on the other hand, is a limiting factor for further evaluation. Four different cases were considered for the depth sensitivity indicating that within the depth ranges considered (15-60 km), the increase of the depth has only a smoothing effect on the synthetic tsunami wave height measurements at the selected TFPs. The strike

  5. Stochastic evaluation of tsunami inundation and quantitative estimating tsunami risk

    International Nuclear Information System (INIS)

    Fukutani, Yo; Anawat, Suppasri; Abe, Yoshi; Imamura, Fumihiko

    2014-01-01

    We performed a stochastic evaluation of tsunami inundation by using results of stochastic tsunami hazard assessment at the Soma port in the Tohoku coastal area. Eleven fault zones along the Japan trench were selected as earthquake faults generating tsunamis. The results show that estimated inundation area of return period about 1200 years had good agreement with that in the 2011 Tohoku earthquake. In addition, we evaluated quantitatively tsunami risk for four types of building; a reinforced concrete, a steel, a brick and a wood at the Soma port by combining the results of inundation assessment and tsunami fragility assessment. The results of quantitative estimating risk would reflect properly vulnerability of the buildings, that the wood building has high risk and the reinforced concrete building has low risk. (author)

  6. The exposure of Sydney (Australia) to earthquake-generated tsunamis, storms and sea level rise: a probabilistic multi-hazard approach.

    Science.gov (United States)

    Dall'Osso, F; Dominey-Howes, D; Moore, C; Summerhayes, S; Withycombe, G

    2014-12-10

    Approximately 85% of Australia's population live along the coastal fringe, an area with high exposure to extreme inundations such as tsunamis. However, to date, no Probabilistic Tsunami Hazard Assessments (PTHA) that include inundation have been published for Australia. This limits the development of appropriate risk reduction measures by decision and policy makers. We describe our PTHA undertaken for the Sydney metropolitan area. Using the NOAA NCTR model MOST (Method for Splitting Tsunamis), we simulate 36 earthquake-generated tsunamis with annual probabilities of 1:100, 1:1,000 and 1:10,000, occurring under present and future predicted sea level conditions. For each tsunami scenario we generate a high-resolution inundation map of the maximum water level and flow velocity, and we calculate the exposure of buildings and critical infrastructure. Results indicate that exposure to earthquake-generated tsunamis is relatively low for present events, but increases significantly with higher sea level conditions. The probabilistic approach allowed us to undertake a comparison with an existing storm surge hazard assessment. Interestingly, the exposure to all the simulated tsunamis is significantly lower than that for the 1:100 storm surge scenarios, under the same initial sea level conditions. The results have significant implications for multi-risk and emergency management in Sydney.

  7. Rapid processing of data based on high-performance algorithms for solving inverse problems and 3D-simulation of the tsunami and earthquakes

    Science.gov (United States)

    Marinin, I. V.; Kabanikhin, S. I.; Krivorotko, O. I.; Karas, A.; Khidasheli, D. G.

    2012-04-01

    We consider new techniques and methods for earthquake and tsunami related problems, particularly - inverse problems for the determination of tsunami source parameters, numerical simulation of long wave propagation in soil and water and tsunami risk estimations. In addition, we will touch upon the issue of database management and destruction scenario visualization. New approaches and strategies, as well as mathematical tools and software are to be shown. The long joint investigations by researchers of the Institute of Mathematical Geophysics and Computational Mathematics SB RAS and specialists from WAPMERR and Informap have produced special theoretical approaches, numerical methods, and software tsunami and earthquake modeling (modeling of propagation and run-up of tsunami waves on coastal areas), visualization, risk estimation of tsunami, and earthquakes. Algorithms are developed for the operational definition of the origin and forms of the tsunami source. The system TSS numerically simulates the source of tsunami and/or earthquakes and includes the possibility to solve the direct and the inverse problem. It becomes possible to involve advanced mathematical results to improve models and to increase the resolution of inverse problems. Via TSS one can construct maps of risks, the online scenario of disasters, estimation of potential damage to buildings and roads. One of the main tools for the numerical modeling is the finite volume method (FVM), which allows us to achieve stability with respect to possible input errors, as well as to achieve optimum computing speed. Our approach to the inverse problem of tsunami and earthquake determination is based on recent theoretical results concerning the Dirichlet problem for the wave equation. This problem is intrinsically ill-posed. We use the optimization approach to solve this problem and SVD-analysis to estimate the degree of ill-posedness and to find the quasi-solution. The software system we developed is intended to

  8. A Review of Methodologies on Vulnerability Assessment of Buildings to Tsunami Damage

    Science.gov (United States)

    Gunasekera, R.; Rosetto, T.; Tabuchi, S.; Suppasri, A.; Futami, T.; Scott, I.; Maegawa, H.

    2012-04-01

    The infrequency, suddenness and violence tsunamis has led to a lack of knowledge on tsunami and lack of data available for the calibration of numerical models particularly in relation to tsunami damage. Therefore, there are very few tsunami structural vulnerability studies available. Of the available literature, most of these started after the disastrous 2004 Indian Ocean event. Most of fragility curves have been developed in some areas struck by the 2004 tsunami, which are very different in architecture and engineering respect to the US, Japanese or European ones. This review aims to highlight the strengths and weaknesses of current knowledge on tsunami fragility by critically assessing several fragility curves based on post tsunami damage surveys in Chile, Japan (including initial findings of the March 2011 event), Samoa, Sri Lanka and Thailand. It is observed that there is no consensus on how to derive tsunami fragility curves. Most of the examined relationships are seen to relate to residential buildings, and, due to the location of recent tsunami occurrences, they mostly represent non-engineered buildings (i.e. all use data from Thailand, Sri Lanka, Samoa, or Sumatra), which limits their usefulness. In the absence of a good understanding of tsunami actions on buildings most existing fragility relationships adopt inundation depth as the hazard parameter in the vulnerability function, which does not account for the other components of onshore flow contributing to tsunami loads on buildings, such as flow velocity.

  9. Seismogeodetic monitoring techniques for tsunami and earthquake early warning and rapid assessment of structural damage

    Science.gov (United States)

    Haase, J. S.; Bock, Y.; Saunders, J. K.; Goldberg, D.; Restrepo, J. I.

    2016-12-01

    As part of an effort to promote the use of NASA-sponsored Earth science information for disaster risk reduction, real-time high-rate seismogeodetic data are being incorporated into early warning and structural monitoring systems. Seismogeodesy combines seismic acceleration and GPS displacement measurements using a tightly-coupled Kalman filter to provide absolute estimates of seismic acceleration, velocity and displacement. Traditionally, the monitoring of earthquakes and tsunamis has been based on seismic networks for estimating earthquake magnitude and slip, and tide gauges and deep-ocean buoys for direct measurement of tsunami waves. Real-time seismogeodetic observations at subduction zones allow for more robust and rapid magnitude and slip estimation that increase warning time in the near-source region. A NASA-funded effort to utilize GPS and seismogeodesy in NOAA's Tsunami Warning Centers in Alaska and Hawaii integrates new modules for picking, locating, and estimating magnitudes and moment tensors for earthquakes into the USGS earthworm environment at the TWCs. In a related project, NASA supports the transition of this research to seismogeodetic tools for disaster preparedness, specifically by implementing GPS and low-cost MEMS accelerometers for structural monitoring in partnership with earthquake engineers. Real-time high-rate seismogeodetic structural monitoring has been implemented on two structures. The first is a parking garage at the Autonomous University of Baja California Faculty of Medicine in Mexicali, not far from the rupture of the 2011 Mw 7.2 El Mayor Cucapah earthquake enabled through a UCMexus collaboration. The second is the 8-story Geisel Library at University of California, San Diego (UCSD). The system has also been installed for several proof-of-concept experiments at the UCSD Network for Earthquake Engineering Simulation (NEES) Large High Performance Outdoor Shake Table. We present MEMS-based seismogeodetic observations from the 10 June

  10. Reducing Vulnerability of Ports and Harbors to Earthquake and Tsunami Hazards

    Science.gov (United States)

    Wood, Nathan J.; Good, James W.; Goodwin, Robert F.

    2002-01-01

    Recent scientific research suggests the Pacific Northwest could experience catastrophic earthquakes in the near future, both from distant and local sources, posing a significant threat to coastal communities. Damage could result from numerous earthquake-related hazards, such as severe ground shaking, soil liquefaction, landslides, land subsidence/uplift, and tsunami inundation. Because of their geographic location, ports and harbors are especially vulnerable to these hazards. Ports and harbors, however, are important components of many coastal communities, supporting numerous activities critical to the local and regional economy and possibly serving as vital post-event, response-recovery transportation links. A collaborative, multi-year initiative is underway to increase the resiliency of Pacific Northwest ports and harbors to earthquake and tsunami hazards, involving Oregon Sea Grant (OSG), Washington Sea Grant (WSG), the National Oceanic and Atmospheric Administration Coastal Services Center (CSC), and the U.S. Geological Survey Center for Science Policy (CSP). Specific products of this research, planning, and outreach initiative include a regional stakeholder issues and needs assessment, a community-based mitigation planning process, a Geographic Information System (GIS) — based vulnerability assessment methodology, an educational web-site and a regional data archive. This paper summarizes these efforts, including results of two pilot port-harbor community projects, one in Yaquina Bay, Oregon and the other in Sinclair Inlet, Washington. Finally, plans are outlined for outreach to other port and harbor communities in the Pacific Northwest and beyond, using "getting started" workshops and a web-based tutorial.

  11. Dense Ocean Floor Network for Earthquakes and Tsunamis; DONET/ DONET2, Part2 -Development and data application for the mega thrust earthquakes around the Nankai trough-

    Science.gov (United States)

    Kaneda, Y.; Kawaguchi, K.; Araki, E.; Matsumoto, H.; Nakamura, T.; Nakano, M.; Kamiya, S.; Ariyoshi, K.; Baba, T.; Ohori, M.; Hori, T.; Takahashi, N.; Kaneko, S.; Donet Research; Development Group

    2010-12-01

    Yoshiyuki Kaneda Katsuyoshi Kawaguchi*, Eiichiro Araki*, Shou Kaneko*, Hiroyuki Matsumoto*, Takeshi Nakamura*, Masaru Nakano*, Shinichirou Kamiya*, Keisuke Ariyoshi*, Toshitaka Baba*, Michihiro Ohori*, Narumi Takakahashi*, and Takane Hori** * Earthquake and Tsunami Research Project for Disaster Prevention, Leading Project , Japan Agency for Marine-Earth Science and Technology (JAMSTEC) **Institute for Research on Earth Evolution, Japan Agency for Marine-Earth Science and Technology (JAMSTEC) DONET (Dense Ocean Floor Network for Earthquakes and Tsunamis) is the real time monitoring system of the Tonankai seismogenic zones around the Nankai trough southwestern Japan. We were starting to develop DONET to perform real time monitoring of crustal activities over there and the advanced early warning system. DONET will provide important and useful data to understand the Nankai trough maga thrust earthquake seismogenic zones and to improve the accuracy of the earthquake recurrence cycle simulation. Details of DONET concept are as follows. 1) Redundancy, Extendable function and advanced maintenance system using the looped cable system, junction boxes and the ROV/AUV. DONET has 20 observatories and incorporated in a double land stations concept. Also, we are developed ROV for the 10km cable extensions and heavy weight operations. 2) Multi kinds of sensors to observe broad band phenomena such as long period tremors, very low frequency earthquakes and strong motions of mega thrust earthquakes over M8: Therefore, sensors such as a broadband seismometer, an accelerometer, a hydrophone, a precise pressure gauge, a differential pressure gauge and a thermometer are equipped with each observatory in DONET. 3) For speedy detections, evaluations and notifications of earthquakes and tsunamis: DONET system will be deployed around the Tonankai seismogenic zone. 4) Provide data of ocean floor crustal deformations derived from pressure sensors: Simultaneously, the development of data

  12. Tsunami source of the 2016 Muisne, Ecuador Earthquake inferred from tide gauge and DART records

    Science.gov (United States)

    Adriano, B.; Fujii, Y.; Koshimura, S.

    2016-12-01

    On April 16, 2016 an earthquake occurred in the central coast of Ecuador (0.382°N 79.922°W, Mw=7.8 at 23:58:36.980 UTC according to U.S. Geological Service). It was reported that widespread damage occurred at several towns of Monabi coastal province. According to reports from the Ecuador Government, more than 15,000 buildings were damaged. This earthquake generated a relatively small tsunami that was detected at several tide gauge station as well as offshore DARTs (Deep Ocean Tsunami Detection Buoys). This study aims to investigate the tsunami source of the 2016 Muisne Earthquake using inversion of recorded tsunami waveform signals. The INOCAR (Instituto Oceanográfico de la Armada in Spanish) of the Ecuador provided the tide records of Esmeraldas, Manta, and La Libertad ports. In addition, the DIMAR (Dirección General Marítima in Spanish) of Colombia provided the tide record of Tumaco port. Finally, waveform signal from two DARTs were also employed. These waveform records usually include ocean tides, which we removed by applying a high-pass filter. To estimate the extent of the tsunami source and the slip distribution, we divide the tsunami source into 4 subfaults that covers the aftershock area during one month after the mainshock. The subfault size is 30 km x 60 km with a top depth of 10 km. The focal mechanisms for all the subfaults were taken form the USGS solution of the mainshock. The inversion result showed that the largest slip was located around the epicenter with a maximum value of 3.1 m. The estimated moment magnitude was calculated as Mw=7.78 (5.89E+20 N-m), which is slightly smaller than the proposed by USGS (Mw7.8, moment 7.05E+20 N-m). The estimated slip distribution suggested that the fault rupture started near the epicenter and propagated from north to south. This evidence is supported by the aftershock distribution, which is higher to the south of the epicenter with a main aftershock of Mw=6.0 on April 22.

  13. Report on the 2010 Chilean earthquake and tsunami response

    Science.gov (United States)

    ,

    2011-01-01

    delegation, it was clear that a multidisciplinary approach was required to properly analyze the emergency response, technical, and social components of this disaster. A diverse and knowledgeable delegation was necessary to analyze the Chilean response in a way that would be beneficial to preparedness in California, as well as improve mitigation efforts around the United States. By most standards, the Maule earthquake was a catastrophe for Chile. The economic losses totaled $30 billion USD or 17% of the GDP of the country. Twelve million people, or ¾ of the population of the country, were in areas that felt strong shaking. Yet only 521 fatalities have been confirmed, with 56 people still missing and presumed dead in the tsunami. The Science and Technology Team evaluated the impacts of the earthquake on built environment with implications for the United States. The fires following the earthquake were minimal in part because of the shutdown of the national electrical grid early in the shaking. Only five engineer-designed buildings were destroyed during the earthquake; however, over 350,000 housing units were destroyed. Chile has a law that holds building owners liable for the first 10 years of a building’s existence for any losses resulting from inadequate application of the building code during construction. This law was cited by many our team met with as a prime reason for the strong performance of the built environment. Overall, this earthquake demonstrated that strict building codes and standards could greatly reduce losses in even the largest earthquakes. In the immediate response to the earthquake and tsunami, first responders, emergency personnel, and search and rescue teams handled many challenges. Loss of communications was significant; many lives were lost and effective coordination to support life-sustaining efforts was gravely impacted due to a lack of inter- and intra-agency coordination. The Health and Medical Services Team sought to understand the medical

  14. Design for tsunami barrier wall based on numerical analyses of tsunami inundation at Shimane Nuclear Power Plant

    International Nuclear Information System (INIS)

    Kiyoshige, Naoya; Yoshitsugu, Shinich; Kawahara, Kazufumi; Ookubo, Yoshimi; Nishihata, Takeshi; Ino, Hitoshi; Kotoura, Tsuyoshi

    2014-01-01

    The conventional tsunami assessment of the active fault beneath the Japan sea in front of the Shimane nuclear power plant and the earthquake feared to happen at the eastern margin of the Japan sea does not expect a huge tsunami as to be assumed on the Pacific sea coast. Hence, the huge tsunami observed at the power plant located near the source of the Tohoku Pacific sea earthquake tsunami whose run-up height reached TP+15m is regarded as the level 2 tsunami for the Shimane nuclear power plant and planned to construct the tsunami barrier walls to endure the supposed level 2 tsunami. In this study, the setting of the Level 2 tsunami by using the numerical analysis based on the non-linear shallow water theory and evaluation for the design tsunami wave pressure exerted on the counter measures by using CADMAS-SURF/3D are discussed. The designed tsunami barrier walls which are suitable to the power plant feasibility and decided from the design tsunami wave pressure distribution based on Tanimoto's formulae and standard earthquake ground motion Ss are also addressed. (author)

  15. Baseline geophysical data for hazard management in coastal areas in relation to earthquakes and tsunamis

    Digital Repository Service at National Institute of Oceanography (India)

    Murthy, K.S.R.

    is another factor for some of the intraplate earthquakes in the South Indian Shield, which includes the Eastern and Western Continental Margins of India. Baseline geophysical data for hazard management in coastal areas in relation to earthquakes... surge. Keywords Hazard management, marine geophysical data, geomorphology and tsunami surge, coastal seismicity Date received: 7 August 2015; accepted: 15 October 2015 CSIR – National Institute of Oceanography, Visakhapatnam, India Corresponding author...

  16. GEODYNAMICS OF NAZCA RIDGE’S OBLIQUE SUBDUCTION AND MIGRATION - IMPLICATIONS FOR TSUNAMI GENERATION ALONG CENTRAL AND SOUTHERN PERU: Earthquake and Tsunami of 23 June 2001

    Directory of Open Access Journals (Sweden)

    George Pararas-Carayannis

    2012-01-01

    Full Text Available Peru is in a region of considerable geologic and seismic complexity. Thrust faulting along the boundary where the Nazca plate subducts beneath the South American continent has created three distinct seismic zones. The angle of subduction of the Nazca oceanic plate beneath the South American plate is not uniform along the entire segment of the Peru-Chile Trench. Furthermore, subduction is affected by buoyancy forces of the bounding oceanic ridges and fractures - such as the Mendana Fracture Zone (MFZ to the North and the Nazca Ridge to the South. This narrow zone is characterized by shallow earthquakes that can generate destructive tsunamis of varied intensities. The present study examines the significance of Nazca Ridge’s oblique subduction and migration to the seismicity of Central/Southern Peru and to tsunami generation. The large tsunamigenic earthquake of 23 June 2001 is presented as a case study. This event generated a destructive, local tsunami that struck Peru’s southern coasts with waves ranging from 3 to 4.6 meters (10-15 feet and inland inundation that ranged from 1 to 3 km. In order to understand the near and far-field tsunamigenic efficiency of events along Central/Southern Peru and the significance of Nazca Ridge’s oblique subduction, the present study examines further the geologic structure of the region and this quake’s moment tensor analysis, energy release, fault rupture and the spatial distribution of aftershocks. Tsunami source mechanism characteristics for this event are presented, as inferred from seismic intensities, energy releases, fault plane solutions and the use of empirical relationships. The study concludes that the segment of subduction and faulting paralleling the Peru-Chile Trench from about 150 to 180 South, as well as the obliquity of convergent tectonic plate collision in this region, may be the reason for shorter rupture lengths of major earthquakes and the generation of only local destructive tsunamis.

  17. The raising of tsunami-wall based on tsunami evaluation at Onagawa nuclear power plant

    International Nuclear Information System (INIS)

    Takahashi, Jun; Hirata, Kazuo

    2017-01-01

    Onagawa nuclear power station (Onagawa NPS) is located on the Pacific coast of Tohoku district where several massive tsunamis had attacked in the past. Based on this natural condition, tsunami safety measures were planned and carried out since the planning of the unit 1. For example, we set appropriate site height for protecting important facilities from tsunamis. As a result, in the massive tsunami which was caused by the 2011 off the Pacific Tohoku Earthquake (3.11 earthquake) on March 11, 2011, all units of Onagawa NPS achieved the cold shutdown. After 3.11 earthquake, we revaluated tsunami considering latest knowledge. In the tsunami re-evaluation, we carried out documents investigation about all tsunami source factors and set the standard fault models which were thought to be appropriate as tsunami wave sources. As a result, the highest water level at the site front is evaluated as 23.1 m. Based on this examination result, we decided to raise the existing seawall (approximately 17 m) to 29 m in consideration of margin and so on. Because the space of the site was limited, we planned a combination of steel-pipe type vertical wall (L = 680 m) and embankment (L = 120 m) due to cement improved soil. (author)

  18. USGS SAFRR Tsunami Scenario: Potential Impacts to the U.S. West Coast from a Plausible M9 Earthquake near the Alaska Peninsula

    Science.gov (United States)

    Ross, S.; Jones, L. M.; Wilson, R. I.; Bahng, B.; Barberopoulou, A.; Borrero, J. C.; Brosnan, D.; Bwarie, J. T.; Geist, E. L.; Johnson, L. A.; Hansen, R. A.; Kirby, S. H.; Knight, E.; Knight, W. R.; Long, K.; Lynett, P. J.; Miller, K. M.; Mortensen, C. E.; Nicolsky, D.; Oglesby, D. D.; Perry, S. C.; Porter, K. A.; Real, C. R.; Ryan, K. J.; Suleimani, E. N.; Thio, H. K.; Titov, V. V.; Wein, A. M.; Whitmore, P.; Wood, N. J.

    2012-12-01

    The U.S. Geological Survey's Science Application for Risk Reduction (SAFRR) project, in collaboration with the California Geological Survey, the California Emergency Management Agency, the National Oceanic and Atmospheric Administration, and other agencies and institutions are developing a Tsunami Scenario to describe in detail the impacts of a tsunami generated by a hypothetical, but realistic, M9 earthquake near the Alaska Peninsula. The overarching objective of SAFRR and its predecessor, the Multi-Hazards Demonstration Project, is to help communities reduce losses from natural disasters. As requested by emergency managers and other community partners, a primary approach has been comprehensive, scientifically credible scenarios that start with a model of a geologic event and extend through estimates of damage, casualties, and societal consequences. The first product was the ShakeOut scenario, addressing a hypothetical earthquake on the southern San Andreas fault, that spawned the successful Great California ShakeOut, an annual event and the nation's largest emergency preparedness exercise. That was followed by the ARkStorm scenario, which addresses California winter storms that surpass hurricanes in their destructive potential. Some of the Tsunami Scenario's goals include developing advanced models of currents and inundation for the event; spurring research related to Alaskan earthquake sources; engaging the port and harbor decision makers; understanding the economic impacts to local, regional and national economy in both the short and long term; understanding the ecological, environmental, and societal impacts of coastal inundation; and creating enhanced communication products for decision-making before, during, and after a tsunami event. The state of California, through CGS and Cal EMA, is using the Tsunami Scenario as an opportunity to evaluate policies regarding tsunami impact. The scenario will serve as a long-lasting resource to teach preparedness and

  19. Real-time correction of tsunami site effect by frequency-dependent tsunami-amplification factor

    Science.gov (United States)

    Tsushima, H.

    2017-12-01

    For tsunami early warning, I developed frequency-dependent tsunami-amplification factor and used it to design a recursive digital filter that can be applicable for real-time correction of tsunami site response. In this study, I assumed that a tsunami waveform at an observing point could be modeled by convolution of source, path and site effects in time domain. Under this assumption, spectral ratio between offshore and the nearby coast can be regarded as site response (i.e. frequency-dependent amplification factor). If the amplification factor can be prepared before tsunamigenic earthquakes, its temporal convolution to offshore tsunami waveform provides tsunami prediction at coast in real time. In this study, tsunami waveforms calculated by tsunami numerical simulations were used to develop frequency-dependent tsunami-amplification factor. Firstly, I performed numerical tsunami simulations based on nonlinear shallow-water theory from many tsuanmigenic earthquake scenarios by varying the seismic magnitudes and locations. The resultant tsunami waveforms at offshore and the nearby coastal observing points were then used in spectral-ratio analysis. An average of the resulted spectral ratios from the tsunamigenic-earthquake scenarios is regarded as frequency-dependent amplification factor. Finally, the estimated amplification factor is used in design of a recursive digital filter that can be applicable in time domain. The above procedure is applied to Miyako bay at the Pacific coast of northeastern Japan. The averaged tsunami-height spectral ratio (i.e. amplification factor) between the location at the center of the bay and the outside show a peak at wave-period of 20 min. A recursive digital filter based on the estimated amplification factor shows good performance in real-time correction of tsunami-height amplification due to the site effect. This study is supported by Japan Society for the Promotion of Science (JSPS) KAKENHI grant 15K16309.

  20. Long-Term Effects of the 2011 Japan Earthquake and Tsunami on Incidence of Fatal and Nonfatal Myocardial Infarction.

    Science.gov (United States)

    Nakamura, Motoyuki; Tanaka, Kentarou; Tanaka, Fumitaka; Matsuura, Yuuki; Komi, Ryousuke; Niiyama, Masanobu; Kawakami, Mikio; Koeda, Yorihiko; Sakai, Toshiaki; Onoda, Toshiyuki; Itoh, Tomonori

    2017-08-01

    This study aimed to examine the long-term effects of the 2011 Japan earthquake and tsunami on the incidence of fatal and nonfatal myocardial infarction (MI). In the present study, the incidence of 2 types of cardiac events was comprehensively recorded. The study area was divided into 2 zones based on the severity of tsunami damage, which was determined by the percentage of the inundated area within the residential area (tsunami (r = 0.77; p tsunami was associated with a continual increase in the incidence of fatal MI among disaster survivors. Copyright © 2017 The Author(s). Published by Elsevier Inc. All rights reserved.

  1. Using GPS to Detect Imminent Tsunamis

    Science.gov (United States)

    Song, Y. Tony

    2009-01-01

    A promising method of detecting imminent tsunamis and estimating their destructive potential involves the use of Global Positioning System (GPS) data in addition to seismic data. Application of the method is expected to increase the reliability of global tsunami-warning systems, making it possible to save lives while reducing the incidence of false alarms. Tsunamis kill people every year. The 2004 Indian Ocean tsunami killed about 230,000 people. The magnitude of an earthquake is not always a reliable indication of the destructive potential of a tsunami. The 2004 Indian Ocean quake generated a huge tsunami, while the 2005 Nias (Indonesia) quake did not, even though both were initially estimated to be of the similar magnitude. Between 2005 and 2007, five false tsunami alarms were issued worldwide. Such alarms result in negative societal and economic effects. GPS stations can detect ground motions of earthquakes in real time, as frequently as every few seconds. In the present method, the epicenter of an earthquake is located by use of data from seismometers, then data from coastal GPS stations near the epicenter are used to infer sea-floor displacements that precede a tsunami. The displacement data are used in conjunction with local topographical data and an advanced theory to quantify the destructive potential of a tsunami on a new tsunami scale, based on the GPS-derived tsunami energy, much like the Richter Scale used for earthquakes. An important element of the derivation of the advanced theory was recognition that horizontal sea-floor motions contribute much more to generation of tsunamis than previously believed. The method produces a reliable estimate of the destructive potential of a tsunami within minutes typically, well before the tsunami reaches coastal areas. The viability of the method was demonstrated in computational tests in which the method yielded accurate representations of three historical tsunamis for which well-documented ground

  2. Tsunami Source Identification on the 1867 Tsunami Event Based on the Impact Intensity

    Science.gov (United States)

    Wu, T. R.

    2014-12-01

    The 1867 Keelung tsunami event has drawn significant attention from people in Taiwan. Not only because the location was very close to the 3 nuclear power plants which are only about 20km away from the Taipei city but also because of the ambiguous on the tsunami sources. This event is unique in terms of many aspects. First, it was documented on many literatures with many languages and with similar descriptions. Second, the tsunami deposit was discovered recently. Based on the literatures, earthquake, 7-meter tsunami height, volcanic smoke, and oceanic smoke were observed. Previous studies concluded that this tsunami was generated by an earthquake with a magnitude around Mw7.0 along the Shanchiao Fault. However, numerical results showed that even a Mw 8.0 earthquake was not able to generate a 7-meter tsunami. Considering the steep bathymetry and intense volcanic activities along the Keelung coast, one reasonable hypothesis is that different types of tsunami sources were existed, such as the submarine landslide or volcanic eruption. In order to confirm this scenario, last year we proposed the Tsunami Reverse Tracing Method (TRTM) to find the possible locations of the tsunami sources. This method helped us ruling out the impossible far-field tsunami sources. However, the near-field sources are still remain unclear. This year, we further developed a new method named 'Impact Intensity Analysis' (IIA). In the IIA method, the study area is divided into a sequence of tsunami sources, and the numerical simulations of each source is conducted by COMCOT (Cornell Multi-grid Coupled Tsunami Model) tsunami model. After that, the resulting wave height from each source to the study site is collected and plotted. This method successfully helped us to identify the impact factor from the near-field potential sources. The IIA result (Fig. 1) shows that the 1867 tsunami event was a multi-source event. A mild tsunami was trigged by a Mw7.0 earthquake, and then followed by the submarine

  3. Seismology on drifting icebergs: Catching earthquakes, tsunamis, swell, and iceberg music

    Science.gov (United States)

    Okal, E. A.; Macayeal, D. R.

    2006-12-01

    For the past 3 years, we have operated seismometers on large icebergs either parked or drifting in the Ross Sea, with an additional station at Nascent, where the next section of the Ross Ice Shelf is expected to calf. Apart from their primary goal of studying in situ tremor generated inside the ice, presumed to arise during collisions and fragmentation, our stations have functioned as teleseismic observatories, despite a noisy environment in the 20-100 mHz frequency band, corresponding to the free bobbing and rolling of the icebergs. As expected, both P and Rayleigh waves from distant earthquakes are recorded on the vertical channels as unperturbed ground motion, with acceptable values of energy flux (P) or magnitude (Rayleigh); however, due to noise level at mantle periods, only Rayleigh waves from the largest events (Sumatra 2004; Nias 2005) could be quantified meaningfully. T waves from distant earthquakes along the EPR can be recorded, but the acoustic-to-seismic transition at the ice boundary is less effcient than at typical island stations. The 2004 Sumatra tsunami was recorded on all 3 components at the 3 stations; the inferred amplitudes (about 15 cm vertical and 1.3 m horizontal, peak-to-peak) are in general agreement with global simulations, and suggest that the bergs rode the tsunami without intrinsic deformation; a small tsunami is also detected for the Macquarie earthquake of 23 Dec. 2004. Our stations regularly recorded long wavetrains in the 40-60 mHz range, dispersed under the deep-water approximation, and corresponding to sea swell propagating across the entire ocean from major storms in the Northern and Equatorial Pacific. In the case of a major depression in the Gulf of Alaska in Late October 2005, recorded on the ice 6 days later, Iceberg B-15A underwent at the same time a severe fragmentation, leading to legitimate speculation on the role of storm waves in triggering its break-up. Finally, our stations recorded a large number of local signals

  4. Large magnitude (M > 7.5) offshore earthquakes in 2012: few examples of absent or little tsunamigenesis, with implications for tsunami early warning

    Science.gov (United States)

    Pagnoni, Gianluca; Armigliato, Alberto; Tinti, Stefano

    2013-04-01

    We take into account some examples of offshore earthquakes occurred worldwide in year 2012 that were characterised by a "large" magnitude (Mw equal or larger than 7.5) but which produced no or little tsunami effects. Here, "little" is intended as "lower than expected on the basis of the parent earthquake magnitude". The examples we analyse include three earthquakes occurred along the Pacific coasts of Central America (20 March, Mw=7.8, Mexico; 5 September, Mw=7.6, Costa Rica; 7 November, Mw=7.5, Mexico), the Mw=7.6 and Mw=7.7 earthquakes occurred respectively on 31 August and 28 October offshore Philippines and offshore Alaska, and the two Indian Ocean earthquakes registered on a single day (11 April) and characterised by Mw=8.6 and Mw=8.2. For each event, we try to face the problem related to its tsunamigenic potential from two different perspectives. The first can be considered purely scientific and coincides with the question: why was the ensuing tsunami so weak? The answer can be related partly to the particular tectonic setting in the source area, partly to the particular position of the source with respect to the coastline, and finally to the focal mechanism of the earthquake and to the slip distribution on the ruptured fault. The first two pieces of information are available soon after the earthquake occurrence, while the third requires time periods in the order of tens of minutes. The second perspective is more "operational" and coincides with the tsunami early warning perspective, for which the question is: will the earthquake generate a significant tsunami and if so, where will it strike? The Indian Ocean events of 11 April 2012 are perfect examples of the fact that the information on the earthquake magnitude and position alone may not be sufficient to produce reliable tsunami warnings. We emphasise that it is of utmost importance that the focal mechanism determination is obtained in the future much more quickly than it is at present and that this

  5. Earthquake engineering for nuclear facilities

    CERN Document Server

    Kuno, Michiya

    2017-01-01

    This book is a comprehensive compilation of earthquake- and tsunami-related technologies and knowledge for the design and construction of nuclear facilities. As such, it covers a wide range of fields including civil engineering, architecture, geotechnical engineering, mechanical engineering, and nuclear engineering, for the development of new technologies providing greater resistance against earthquakes and tsunamis. It is crucial both for students of nuclear energy courses and for young engineers in nuclear power generation industries to understand the basics and principles of earthquake- and tsunami-resistant design of nuclear facilities. In Part I, "Seismic Design of Nuclear Power Plants", the design of nuclear power plants to withstand earthquakes and tsunamis is explained, focusing on buildings, equipment's, and civil engineering structures. In Part II, "Basics of Earthquake Engineering", fundamental knowledge of earthquakes and tsunamis as well as the dynamic response of structures and foundation ground...

  6. Integrating Caribbean Seismic and Tsunami Hazard into Public Policy and Action

    Science.gov (United States)

    von Hillebrandt-Andrade, C.

    2012-12-01

    The Caribbean has a long history of tsunamis and earthquakes. Over the past 500 years, more than 80 tsunamis have been documented in the region by the NOAA National Geophysical Data Center. Almost 90% of all these historical tsunamis have been associated with earthquakes. Just since 1842, 3510 lives have been lost to tsunamis; this is more than in the Northeastern Pacific for the same time period. With a population of almost 160 million and a heavy concentration of residents, tourists, businesses and critical infrastructure along the Caribbean shores (especially in the northern and eastern Caribbean), the risk to lives and livelihoods is greater than ever before. Most of the countries also have a very high exposure to earthquakes. Given the elevated vulnerability, it is imperative that government officials take steps to mitigate the potentially devastating effects of these events. Nevertheless, given the low frequency of high impact earthquakes and tsunamis, in comparison to hurricanes, combined with social and economic considerations, the needed investments are not made and disasters like the 2010 Haiti earthquake occur. In the absence of frequent significant events, an important driving force for public officials to take action, is the dissemination of scientific studies. When papers of this nature have been published and media advisories issued, public officials demonstrate heightened interest in the topic which in turn can lead to increased legislation and funding efforts. This is especially the case if the material can be easily understood by the stakeholders and there is a local contact. In addition, given the close link between earthquakes and tsunamis, in Puerto Rico alone, 50% of the high impact earthquakes have also generated destructive tsunamis, it is very important that earthquake and tsunami hazards studies demonstrate consistency. Traditionally in the region, earthquake and tsunami impacts have been considered independently in the emergency planning

  7. Three Kanto Earthquakes Inferred from the Tsunami Deposits and the Relative Sea Level Change in the Miura Peninsula, Central Japan

    Science.gov (United States)

    Kim, H.; Shimazaki, K.; Chiba, T.; Ishibe, T.; Okamura, M.; Matsuoka, H.; Tsuji, Y.; Satake, K.

    2010-12-01

    The Kanto earthquake is a great interplate earthquake caused by subduction of the Philippine Sea Plate beneath the Japan Island along the Sagami Trough. The 1923 Kanto earthquake (M=7.9) and the 1703 Kanto earthquake (M~8.0) are two of the most devastating earthquake those struck Tokyo Metropolitan area, respectively. These earthquakes brought large (~5 m) tsunami to the coast area and uplifted the Miura peninsula by ~1.4 m. The tide gauge station, moreover, records the subsidence during the interseismic period before and after the 1923 earthquake. Present study clarifies the past Kanto earthquake prior to the 1703 earthquake based on the sedimentary analysis in the Koajiro bay of the southern Miura Peninsula. The continuous samples of inner bay fine sediments were taken by the boring survey using 3-m-long geoslicer. Three layers of coarse sediments, T1, T2, and T3 units from top toward bottom, are observed in the bay sediments at almost all the sites. These units are composed of mixture of materials such as shell fragments, rock clasts and gravel, and some of units have eroded the lower fine sediments, indicating the event deposits by the strong traction flow. The grain sizes of the bay sediments are grading upward and abruptly become larger after the deposition of the T1, T2 and T3 units. Very little diatom is observed in these units, but the total number of diatoms increase in the bay sediments. The ratio of the marine planktonic species against the benthic species gradually rises from the lower part to the upper part in the bay sediment. In the tidal flat sediment, the freshwater planktonic species appear in place of the marine planktonic diatom. The changes of grain size and diatom species make a presumption that the sea depth suddenly becomes shallow by the event and deeper during the interseismic period. The T1, T2 and T3 units, thus, are correlated with the tsunami deposits conveyed by the Kanto earthquake. The T1 and T2 units are inferred to be the tsunami

  8. Research to Operations: From Point Positions, Earthquake and Tsunami Modeling to GNSS-augmented Tsunami Early Warning

    Science.gov (United States)

    Stough, T.; Green, D. S.

    2017-12-01

    This collaborative research to operations demonstration brings together the data and algorithms from NASA research, technology, and applications-funded projects to deliver relevant data streams, algorithms, predictive models, and visualization tools to the NOAA National Tsunami Warning Center (NTWC) and Pacific Tsunami Warning Center (PTWC). Using real-time GNSS data and models in an operational environment, we will test and evaluate an augmented capability for tsunami early warning. Each of three research groups collect data from a selected network of real-time GNSS stations, exchange data consisting of independently processed 1 Hz station displacements, and merge the output into a single, more accurate and reliable set. The resulting merged data stream is delivered from three redundant locations to the TWCs with a latency of 5-10 seconds. Data from a number of seismogeodetic stations with collocated GPS and accelerometer instruments are processed for displacements and seismic velocities and also delivered. Algorithms for locating and determining the magnitude of earthquakes as well as algorithms that compute the source function of a potential tsunami using this new data stream are included in the demonstration. The delivered data, algorithms, models and tools are hosted on NOAA-operated machines at both warning centers, and, once tested, the results will be evaluated for utility in improving the speed and accuracy of tsunami warnings. This collaboration has the potential to dramatically improve the speed and accuracy of the TWCs local tsunami information over the current seismometer-only based methods. In our first year of this work, we have established and deployed an architecture for data movement and algorithm installation at the TWC's. We are addressing data quality issues and porting algorithms into the TWCs operating environment. Our initial module deliveries will focus on estimating moment magnitude (Mw) from Peak Ground Displacement (PGD), within 2

  9. Ray Tracing for Dispersive Tsunamis and Source Amplitude Estimation Based on Green's Law: Application to the 2015 Volcanic Tsunami Earthquake Near Torishima, South of Japan

    Science.gov (United States)

    Sandanbata, Osamu; Watada, Shingo; Satake, Kenji; Fukao, Yoshio; Sugioka, Hiroko; Ito, Aki; Shiobara, Hajime

    2018-04-01

    Ray tracing, which has been widely used for seismic waves, was also applied to tsunamis to examine the bathymetry effects during propagation, but it was limited to linear shallow-water waves. Green's law, which is based on the conservation of energy flux, has been used to estimate tsunami amplitude on ray paths. In this study, we first propose a new ray tracing method extended to dispersive tsunamis. By using an iterative algorithm to map two-dimensional tsunami velocity fields at different frequencies, ray paths at each frequency can be traced. We then show that Green's law is valid only outside the source region and that extension of Green's law is needed for source amplitude estimation. As an application example, we analyzed tsunami waves generated by an earthquake that occurred at a submarine volcano, Smith Caldera, near Torishima, Japan, in 2015. The ray-tracing results reveal that the ray paths are very dependent on its frequency, particularly at deep oceans. The validity of our frequency-dependent ray tracing is confirmed by the comparison of arrival angles and travel times with those of observed tsunami waveforms at an array of ocean bottom pressure gauges. The tsunami amplitude at the source is nearly twice or more of that just outside the source estimated from the array tsunami data by Green's law.

  10. Scientific Animations for Tsunami Hazard Mitigation: The Pacific Tsunami Warning Center's YouTube Channel

    Science.gov (United States)

    Becker, N. C.; Wang, D.; Shiro, B.; Ward, B.

    2013-12-01

    Outreach and education save lives, and the Pacific Tsunami Warning Center (PTWC) has a new tool--a YouTube Channel--to advance its mission to protect lives and property from dangerous tsunamis. Such outreach and education is critical for coastal populations nearest an earthquake since they may not get an official warning before a tsunami reaches them and will need to know what to do when they feel strong shaking. Those who live far enough away to receive useful official warnings and react to them, however, can also benefit from PTWC's education and outreach efforts. They can better understand a tsunami warning message when they receive one, can better understand the danger facing them, and can better anticipate how events will unfold while the warning is in effect. The same holds true for emergency managers, who have the authority to evacuate the public they serve, and for the news media, critical partners in disseminating tsunami hazard information. PTWC's YouTube channel supplements its formal outreach and education efforts by making its computer animations available 24/7 to anyone with an Internet connection. Though the YouTube channel is only a month old (as of August 2013), it should rapidly develop a large global audience since similar videos on PTWC's Facebook page have reached over 70,000 viewers during organized media events, while PTWC's official web page has received tens of millions of hits during damaging tsunamis. These animations are not mere cartoons but use scientific data and calculations to render graphical depictions of real-world phenomena as accurately as possible. This practice holds true whether the animation is a simple comparison of historic earthquake magnitudes or a complex simulation cycling through thousands of high-resolution data grids to render tsunami waves propagating across an entire ocean basin. PTWC's animations fall into two broad categories. The first group illustrates concepts about seismology and how it is critical to

  11. Local Tsunami Warnings using GNSS and Seismic Data.

    Science.gov (United States)

    Hirshorn, B. F.

    2017-12-01

    Tsunami warning Centers (TWC's) must issue warnings based on imperfect and limited data. Uncertainties increase in the near field, where a tsunami reaches the closest coastal populations to the causative earthquake in a half hour or less. In the absence of a warning, the usual advice is "When the ground shakes so severely that it's difficult to stand, move uphill and away from the coast." But, what if the shaking is not severe? If, for example, the earthquake ruptures slowly (producing very little perceived shaking) this advice will fail. Unfortunately these "Tsunami" earthquakes are not rare: tsunamis from slow earthquakes off of Nicaragua in 1992, and Java in 1994 and 2006, killed 179, 250 and 637 people, respectively, even though very few nearby coastal residents felt any strong ground shaking. TWC's must therefore warn the closest coastal populations to the causative earthquake, where over 80% of the Tsunami based casualties typically occur, as soon possible after earthquake rupture begins. The NWS Tsunami Warning Centers (TWCs) currently issue local Tsunami Warnings for the US West Coast, Hawaii, and the Puerto Rico - Virgin Island region within 2-4 minutes after origin time. However, our initial short period Magnitude estimates saturate over about Mw 6.5, and Mwp underestimates Mw for events larger than about Mw 7.5 when using data in the 0 to 3 degree epicentral distance range, severely underestimating the danger of a potential Tsunami in the near field. Coastal GNSS networks complement seismic monitoring networks, and enable unsaturated estimates of Mw within 2-3 minutes of earthquake origin time. NASA/JPL, SIO, USGS, CWU, UCB and UW, with funding and guidance from NASA, and leveraging the USGS funded ShakeAlert development, have been working with the National Weather Service TWC's to incorporate real-time GNSS and seismogeodetic data into their operations. These data will soon provide unsaturated estimates of moment magnitude, Centroid Moment Tensor

  12. Mathematical Modelling of Tsunami Propagation | Eze | Journal of ...

    African Journals Online (AJOL)

    The generation of tsunamis with the help of a simple dislocation model of an earthquake and their propagation in the basin are discussed. In this study, we examined the formation of a tsunami wave from an initial sea surface displacement similar to those obtained from earthquakes that have generated tsunami waves and ...

  13. Improving the coastal record of tsunamis in the ESI-07 scale: Tsunami Environmental Effects Scale (TEE-16 scale)

    Energy Technology Data Exchange (ETDEWEB)

    Lario, J.; Bardaji, T.; Silva, P.G.; Zazo, C.; Goy, J.L.

    2016-07-01

    This paper discusses possibilities to improve the Environmental Seismic Intensity Scale (ESI-07 scale), a scale based on the effects of earthquakes in the environment. This scale comprises twelve intensity degrees and considers primary and secondary effects, one of them the occurrence of tsunamis. Terminology and physical tsunami parameters corresponding to different intensity levels are often misleading and confusing. The present work proposes: i) a revised and updated catalogue of environmental and geological effects of tsunamis, gathering all the available information on Tsunami Environmental Effects (TEEs) produced by recent earthquake-tsunamis; ii) a specific intensity scale (TEE-16) for the effects of tsunamis in the natural environment at coastal areas. The proposed scale could be used in future tsunami events and, in historic and paleo-tsunami studies. The new TEE- 16 scale incorporates the size specific parameters already considered in the ESI-07 scale, such as wave height, run-up and inland extension of inundation, and a comprehensive and more accurate terminology that covers all the different intensity levels identifiable in the geological record (intensities VI-XII). The TEE-16 scale integrates the description and quantification of the potential sedimentary and erosional features (beach scours, transported boulders and classical tsunamites) derived from different tsunami events at diverse coastal environments (e.g. beaches, estuaries, rocky cliffs,). This new approach represents an innovative advance in relation to the tsunami descriptions provided by the ESI-07 scale, and allows the full application of the proposed scale in paleoseismological studies. The analysis of the revised and updated tsunami environmental damage suggests that local intensities recorded in coastal areas do not correlate well with the TEE-16 intensity (normally higher), but shows a good correlation with the earthquake magnitude (Mw). Tsunamis generated by earthquakes can then be

  14. Study on business resilience factors toward earthquake and tsunami - A case study of Padang city

    Science.gov (United States)

    Rahayu, Harkunti P.; Aini, Qurrata; Putri, Amalia Novianti

    2017-07-01

    As as the Capital of West Sumatera Province and as the largest city at the West Coast of Sumatera, the City of Padang has been assigned as one of the National Activity Center for Regional Economic Development. The city will be developed as a metropolitan city, which will be very much relied on the multi sectoral support such as business, services, industry, and tourism sectors. However, the city is located at a very high-risk zone for earthquake and tsunami. After 2004 Indian Ocean Tsunami, the city has been stricken several times by large earthquake and tsunami threat, for example in 8.4 M September 2007 and 7.6 M September 2009 causing major casualties, severe damages, great economic loss as well as tsunami threat to the people. Without disaster risk reduction based development planning, the goal of Padang as metropolitan and National Activity Center is difficult to be achieved. Knowing the level of risk and its appropriate countermeasures from the perspective of business resilience becomes very important. Thus, this paper will present the detail study on business reliency for the Padang City, starting from (i) Earthquake and Tsunami Risk Assessment from the perspective of preparedness for Business in Padang Barat Subdistrict of Padang City, (ii) Assessment of resiliency level of Padang City Business after the 2009 event, and (iii) recommendation for considering the Business Resilience factors as part of DRR based CBD development Plan of Padang Barat sub district - Padang City. This study is not only able to identify physical and nonphusical aspect of business characteristic, but it has identified four major components of Bussiness Resiliency Indicators, i.e. Swift Recovery Factors (RR), Experience and Knowledge to Disaster (PP), Emergency Response Plan (RT) and Asset Protection (PA). Each major indicator consists of several indicators, with 19 total indicators. Further investigation on these indicators shown that total performance value of business resiliency is

  15. Improving tsunami resiliency: California's Tsunami Policy Working Group

    Science.gov (United States)

    Real, Charles R.; Johnson, Laurie; Jones, Lucile M.; Ross, Stephanie L.; Kontar, Y.A.; Santiago-Fandiño, V.; Takahashi, T.

    2014-01-01

    California has established a Tsunami Policy Working Group to facilitate development of policy recommendations for tsunami hazard mitigation. The Tsunami Policy Working Group brings together government and industry specialists from diverse fields including tsunami, seismic, and flood hazards, local and regional planning, structural engineering, natural hazard policy, and coastal engineering. The group is acting on findings from two parallel efforts: The USGS SAFRR Tsunami Scenario project, a comprehensive impact analysis of a large credible tsunami originating from an M 9.1 earthquake in the Aleutian Islands Subduction Zone striking California’s coastline, and the State’s Tsunami Preparedness and Hazard Mitigation Program. The unique dual-track approach provides a comprehensive assessment of vulnerability and risk within which the policy group can identify gaps and issues in current tsunami hazard mitigation and risk reduction, make recommendations that will help eliminate these impediments, and provide advice that will assist development and implementation of effective tsunami hazard risk communication products to improve community resiliency.

  16. Chapter two: Phenomenology of tsunamis II: scaling, event statistics, and inter-event triggering

    Science.gov (United States)

    Geist, Eric L.

    2012-01-01

    Observations related to tsunami catalogs are reviewed and described in a phenomenological framework. An examination of scaling relationships between earthquake size (as expressed by scalar seismic moment and mean slip) and tsunami size (as expressed by mean and maximum local run-up and maximum far-field amplitude) indicates that scaling is significant at the 95% confidence level, although there is uncertainty in how well earthquake size can predict tsunami size (R2 ~ 0.4-0.6). In examining tsunami event statistics, current methods used to estimate the size distribution of earthquakes and landslides and the inter-event time distribution of earthquakes are first reviewed. These methods are adapted to estimate the size and inter-event distribution of tsunamis at a particular recording station. Using a modified Pareto size distribution, the best-fit power-law exponents of tsunamis recorded at nine Pacific tide-gauge stations exhibit marked variation, in contrast to the approximately constant power-law exponent for inter-plate thrust earthquakes. With regard to the inter-event time distribution, significant temporal clustering of tsunami sources is demonstrated. For tsunami sources occurring in close proximity to other sources in both space and time, a physical triggering mechanism, such as static stress transfer, is a likely cause for the anomalous clustering. Mechanisms of earthquake-to-earthquake and earthquake-to-landslide triggering are reviewed. Finally, a modification of statistical branching models developed for earthquake triggering is introduced to describe triggering among tsunami sources.

  17. Washington Tsunami Hazard Mitigation Program

    Science.gov (United States)

    Walsh, T. J.; Schelling, J.

    2012-12-01

    Washington State has participated in the National Tsunami Hazard Mitigation Program (NTHMP) since its inception in 1995. We have participated in the tsunami inundation hazard mapping, evacuation planning, education, and outreach efforts that generally characterize the NTHMP efforts. We have also investigated hazards of significant interest to the Pacific Northwest. The hazard from locally generated earthquakes on the Cascadia subduction zone, which threatens tsunami inundation in less than hour following a magnitude 9 earthquake, creates special problems for low-lying accretionary shoreforms in Washington, such as the spits of Long Beach and Ocean Shores, where high ground is not accessible within the limited time available for evacuation. To ameliorate this problem, we convened a panel of the Applied Technology Council to develop guidelines for construction of facilities for vertical evacuation from tsunamis, published as FEMA 646, now incorporated in the International Building Code as Appendix M. We followed this with a program called Project Safe Haven (http://www.facebook.com/ProjectSafeHaven) to site such facilities along the Washington coast in appropriate locations and appropriate designs to blend with the local communities, as chosen by the citizens. This has now been completed for the entire outer coast of Washington. In conjunction with this effort, we have evaluated the potential for earthquake-induced ground failures in and near tsunami hazard zones to help develop cost estimates for these structures and to establish appropriate tsunami evacuation routes and evacuation assembly areas that are likely to to be available after a major subduction zone earthquake. We intend to continue these geotechnical evaluations for all tsunami hazard zones in Washington.

  18. Parallelization of the Coupled Earthquake Model

    Science.gov (United States)

    Block, Gary; Li, P. Peggy; Song, Yuhe T.

    2007-01-01

    This Web-based tsunami simulation system allows users to remotely run a model on JPL s supercomputers for a given undersea earthquake. At the time of this reporting, predicting tsunamis on the Internet has never happened before. This new code directly couples the earthquake model and the ocean model on parallel computers and improves simulation speed. Seismometers can only detect information from earthquakes; they cannot detect whether or not a tsunami may occur as a result of the earthquake. When earthquake-tsunami models are coupled with the improved computational speed of modern, high-performance computers and constrained by remotely sensed data, they are able to provide early warnings for those coastal regions at risk. The software is capable of testing NASA s satellite observations of tsunamis. It has been successfully tested for several historical tsunamis, has passed all alpha and beta testing, and is well documented for users.

  19. Tsunami Simulation Method Assimilating Ocean Bottom Pressure Data Near a Tsunami Source Region

    Science.gov (United States)

    Tanioka, Yuichiro

    2018-02-01

    A new method was developed to reproduce the tsunami height distribution in and around the source area, at a certain time, from a large number of ocean bottom pressure sensors, without information on an earthquake source. A dense cabled observation network called S-NET, which consists of 150 ocean bottom pressure sensors, was installed recently along a wide portion of the seafloor off Kanto, Tohoku, and Hokkaido in Japan. However, in the source area, the ocean bottom pressure sensors cannot observe directly an initial ocean surface displacement. Therefore, we developed the new method. The method was tested and functioned well for a synthetic tsunami from a simple rectangular fault with an ocean bottom pressure sensor network using 10 arc-min, or 20 km, intervals. For a test case that is more realistic, ocean bottom pressure sensors with 15 arc-min intervals along the north-south direction and sensors with 30 arc-min intervals along the east-west direction were used. In the test case, the method also functioned well enough to reproduce the tsunami height field in general. These results indicated that the method could be used for tsunami early warning by estimating the tsunami height field just after a great earthquake without the need for earthquake source information.

  20. Numerical modelling and evacuation strategies for tsunami awareness: lessons from the 2012 Haida Gwaii Tsunami

    Directory of Open Access Journals (Sweden)

    Angela Santos

    2016-07-01

    Full Text Available On October 28, 2012, an earthquake occurred offshore Canada, with a magnitude Mw of 7.8, triggering a tsunami that propagated through the Pacific Ocean. The tsunami numerical model results show it would not be expected to generate widespread inundation on Hawaii. Yet, two hours after the earthquake, the Pacific Tsunami Warning Centre (PTWC issued a tsunami warning to the state of Hawaii. Since the state was hit by several tsunamis in the past, regular siren exercises, tsunami hazard maps and other prevention measures are available for public use, revealing that residents are well prepared regarding tsunami evacuation procedures. Nevertheless, residents and tourists evacuated mostly by car, and because of that, heavy traffic was reported, showing that it was a non-viable option for evacuation. The tsunami caused minor damages on the coastline, and several car accidents were reported, with one fatality. In recent years, there has been a remarkable interest in tsunami impacts. However, if risk planners seem to be very knowledgeable about how to avoid or mitigate their potential harmful effects, they seem to disregard its integration with other sectors of human activity and other social factors.

  1. Changes in Tsunami Risk Perception in Northern Chile After the April 1 2014 Tsunami

    Science.gov (United States)

    Carvalho, L.; Lagos, M.

    2016-12-01

    Tsunamis are a permanent risk in the coast of Chile. Apart from that, the coastal settlements and the Chilean State, historically, have underestimated the danger of tsunamis. On April 1 2014, a magnitude Mw 8.2 earthquake and a minor tsunami occurred off the coast of northern Chile. Considering that over decades this region has been awaiting an earthquake that would generate a large tsunami, in this study we inquired if the familiarity with the subject tsunami and the lack of frequent tsunamis or occurrence of non-hazardous tsunamis for people could lead to adaptive responses to underestimate the danger. The purpose of this study was to evaluate the perceived risk of tsunami in the city of Arica, before and after the April 1 2014 event. A questionnaire was designed and applied in two time periods to 547 people living in low coastal areas in Arica. In the first step, the survey was applied in March 2014. While in step 2, new questions were included and the survey was reapplied, a year after the minor tsunami. A descriptive analysis of data was performed, followed by a comparison between means. We identified illusion of invulnerability, especially regarding to assessment that preparedness and education actions are enough. Answers about lack of belief in the occurrence of future tsunamis were also reported. At the same time, there were learning elements identified. After April 1, a larger number of participants described self-protection actions for emergency, as well as performing of preventive actions. In addition, we mapped answers about the tsunami danger degree in different locations in the city, where we observed a high knowledge of it. When compared with other hazards, the concern about tsunamis were very high, lower than earthquakes hazard, but higher than pollution, crime and rain. Moreover, we identified place attachment in answers about sense of security and affective bonds with home and their location. We discussed the relationship between risk perception

  2. S-net : Construction of large scale seafloor observatory network for tsunamis and earthquakes along the Japan Trench

    Science.gov (United States)

    Mochizuki, M.; Uehira, K.; Kanazawa, T.; Shiomi, K.; Kunugi, T.; Aoi, S.; Matsumoto, T.; Sekiguchi, S.; Yamamoto, N.; Takahashi, N.; Nakamura, T.; Shinohara, M.; Yamada, T.

    2017-12-01

    NIED has launched the project of constructing a seafloor observatory network for tsunamis and earthquakes after the occurrence of the 2011 Tohoku Earthquake to enhance reliability of early warnings of tsunamis and earthquakes. The observatory network was named "S-net". The S-net project has been financially supported by MEXT.The S-net consists of 150 seafloor observatories which are connected in line with submarine optical cables. The total length of submarine optical cable is about 5,500 km. The S-net covers the focal region of the 2011 Tohoku Earthquake and its vicinity regions. Each observatory equips two units of a high sensitive pressure gauges as a tsunami meter and four sets of three-component seismometers. The S-net is composed of six segment networks. Five of six segment networks had been already installed. Installation of the last segment network covering the outer rise area have been finally finished by the end of FY2016. The outer rise segment has special features like no other five segments of the S-net. Those features are deep water and long distance. Most of 25 observatories on the outer rise segment are located at the depth of deeper than 6,000m WD. Especially, three observatories are set on the seafloor of deeper than about 7.000m WD, and then the pressure gauges capable of being used even at 8,000m WD are equipped on those three observatories. Total length of the submarine cables of the outer rise segment is about two times longer than those of the other segments. The longer the cable system is, the higher voltage supply is needed, and thus the observatories on the outer rise segment have high withstanding voltage characteristics. We employ a dispersion management line of a low loss formed by combining a plurality of optical fibers for the outer rise segment cable, in order to achieve long-distance, high-speed and large-capacity data transmission Installation of the outer rise segment was finished and then full-scale operation of S-net has started

  3. The Study to Improve Tsunami Preparedness Education in Turkey

    Science.gov (United States)

    Sakamoto, Mayumi; Tanırcan, Gülüm; Kaneda, Yoshiyuki; Puskulcu, Seyhun; Kumamoto, Kunihiko

    2016-04-01

    Compared to its long history on disastrous earthquakes, disaster education history in Turkey is rather short. It has just started with an initiative of Disaster Preparedness Education Unit of Bogazici University (BU/DPEU) after 1999 Kocaeli Earthquake. Training modules and materials on disaster preparedness were prepared both for students, teachers and community. Regarding to the school education, the Ministry of National Education (MoNE) reformed their education plan in 2003, and disaster education became one of eight focused components for primary-middle education. In 2011-2014 MoNE had conducted "School-based Disaster Education Project" in collaboration with Japan International Cooperation Agency (JICA). The majority of the school education materials focus more on earthquake and there are very few education programs on tsunami. Within the MarDiM (Earthquake and Tsunami Disaster Mitigation in the Marmara Region and Disaster Education in Turkey) project between Turkey and Japan a multidisciplinary engineering research as well as development of disaster education, tsunami education booklet and video were newly developed in 2015. In order to investigate students' knowledge natural disasters and disaster preparedness with focus on tsunami, a questionnaire based survey was conducted. The survey aims to clarify following questions: 1) how students obtain natural disaster information, 2) how students prepare for natural disaster, 3) knowledge on tsunami (hazard mechanism, evacuation behavior, historical disaster). The study was conducted by BU/DPEU in 2015 and 375 students answered the questionnaire. Results showed that students have more interest on earthquake, flood, tsunami and landslide followed it. Most students have heard about tsunami and the school is a key resource of their information. They know relatively well about tsunami mechanism, however, they have less knowledge on tsunami evacuation behavior and tsunami history in Turkey. In order to let students have

  4. Highly variable recurrence of tsunamis in the 7,400 years before the 2004 Indian Ocean tsunami

    Science.gov (United States)

    Horton, B.; Rubin, C. M.; Sieh, K.; Jessica, P.; Daly, P.; Ismail, N.; Parnell, A. C.

    2017-12-01

    The devastating 2004 Indian Ocean tsunami caught millions of coastal residents and the scientific community off-guard. Subsequent research in the Indian Ocean basin has identified prehistoric tsunamis, but the timing and recurrence intervals of such events are uncertain. Here, we identify coastal caves as a new depositional environment for reconstructing tsunami records and present a 5,000 year record of continuous tsunami deposits from a coastal cave in Sumatra, Indonesia which shows the irregular recurrence of 11 tsunamis between 7,400 and 2,900 years BP. The data demonstrates that the 2004 tsunami was just the latest in a sequence of devastating tsunamis stretching back to at least the early Holocene and suggests a high likelihood for future tsunamis in the Indian Ocean. The sedimentary record in the cave shows that ruptures of the Sunda megathrust vary between large (which generated the 2004 Indian Ocean tsunami) and smaller slip failures. The chronology of events suggests the recurrence of multiple smaller tsunamis within relatively short time periods, interrupted by long periods of strain accumulation followed by giant tsunamis. The average time period between tsunamis is about 450 years with intervals ranging from a long, dormant period of over 2,000 years, to multiple tsunamis within the span of a century. The very long dormant period suggests that the Sunda megathrust is capable of accumulating large slip deficits between earthquakes. Such a high slip rupture would produce a substantially larger earthquake than the 2004 event. Although there is evidence that the likelihood of another tsunamigenic earthquake in Aceh province is high, these variable recurrence intervals suggest that long dormant periods may follow Sunda Megathrust ruptures as large as that of 2004 Indian Ocean tsunami. The remarkable variability of recurrence suggests that regional hazard mitigation plans should be based upon the high likelihood of future destructive tsunami demonstrated by

  5. Impacts of tides on tsunami propagation due to potential Nankai Trough earthquakes in the Seto Inland Sea, Japan

    Science.gov (United States)

    Lee, Han Soo; Shimoyama, Tomohisa; Popinet, Stéphane

    2015-10-01

    The impacts of tides on extreme tsunami propagation due to potential Nankai Trough earthquakes in the Seto Inland Sea (SIS), Japan, are investigated through numerical experiments. Tsunami experiments are conducted based on five scenarios that consider tides at four different phases, such as flood, high, ebb, and low tides. The probes that were selected arbitrarily in the Bungo and Kii Channels show less significant effects of tides on tsunami heights and the arrival times of the first waves than those that experience large tidal ranges in inner basins and bays of the SIS. For instance, the maximum tsunami height and the arrival time at Toyomaesi differ by more than 0.5 m and nearly 1 h, respectively, depending on the tidal phase. The uncertainties defined in terms of calculated maximum tsunami heights due to tides illustrate that the calculated maximum tsunami heights in the inner SIS with standing tides have much larger uncertainties than those of two channels with propagating tides. Particularly in Harima Nada, the uncertainties due to the impacts of tides are greater than 50% of the tsunami heights without tidal interaction. The results recommend simulate tsunamis together with tides in shallow water environments to reduce the uncertainties involved with tsunami modeling and predictions for tsunami hazards preparedness. This article was corrected on 26 OCT 2015. See the end of the full text for details.

  6. Tsunami hazard

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2013-08-15

    Tohoku Earthquake Tsunami on 11 March, 2011 has led the Fukushima Daiichi nuclear power plant to a serious accident, which highlighted a variety of technical issues such as a very low design tsunami height and insufficient preparations in case a tsunami exceeding the design tsunami height. Lessons such as to take measures to be able to maintain the important safety features of the facility for tsunamis exceeding design height and to implement risk management utilizing Probabilistic Safety Assessment are shown. In order to implement the safety assessment on nuclear power plants across Japan accordingly to the back-fit rule, Nuclear Regulatory Commission will promulgate/execute the New Safety Design Criteria in July 2013. JNES has positioned the 'enhancement of probabilistic tsunami hazard assessment' as highest priority issue and implemented in order to support technically the Nuclear Regulatory Authority in formulating the new Safety Design Criteria. Findings of the research had reflected in the 'Technical Review Guidelines for Assessing Design Tsunami Height based on tsunami hazards'. (author)

  7. Analysis of community tsunami evacuation time: An overview

    Science.gov (United States)

    Yunarto, Y.; Sari, A. M.

    2018-02-01

    Tsunami in Indonesia is defined as local tsunami due to its occurrences which are within a distance of 200 km from the epicenter of the earthquake. A local tsunami can be caused by an earthquake, landslide, or volcanic eruption. Tsunami arrival time in Indonesia is generally between 10-60 minutes. As the estimated time of the tsunami waves to reach the coast is 30 minutes after the earthquake, the community should go to the vertical or horizontal evacuation in less than 30 minutes. In an evacuation, the city frequently does the evacuation after obtaining official directions from the authorities. Otherwise, they perform an independent evacuation without correct instructions from the authorities. Both of these ways have several strengths and limitations. This study analyzes these methods regarding time as well as the number of people expected to be saved.

  8. A Tsunami Model for Chile for (Re) Insurance Purposes

    Science.gov (United States)

    Arango, Cristina; Rara, Vaclav; Puncochar, Petr; Trendafiloski, Goran; Ewing, Chris; Podlaha, Adam; Vatvani, Deepak; van Ormondt, Maarten; Chandler, Adrian

    2014-05-01

    Catastrophe models help (re)insurers to understand the financial implications of catastrophic events such as earthquakes and tsunamis. In earthquake-prone regions such as Chile,(re)insurers need more sophisticated tools to quantify the risks facing their businesses, including models with the ability to estimate secondary losses. The 2010 (M8.8) Maule (Chile) earthquake highlighted the need for quantifying losses from secondary perils such as tsunamis, which can contribute to the overall event losses but are not often modelled. This paper presents some key modelling aspects of a new earthquake catastrophe model for Chile developed by Impact Forecasting in collaboration with Aon Benfield Research partners, focusing on the tsunami component. The model has the capability to model tsunami as a secondary peril - losses due to earthquake (ground-shaking) and induced tsunamis along the Chilean coast are quantified in a probabilistic manner, and also for historical scenarios. The model is implemented in the IF catastrophe modelling platform, ELEMENTS. The probabilistic modelling of earthquake-induced tsunamis uses a stochastic event set that is consistent with the seismic (ground shaking) hazard developed for Chile, representing simulations of earthquake occurrence patterns for the region. Criteria for selecting tsunamigenic events (from the stochastic event set) are proposed which take into consideration earthquake location, depth and the resulting seabed vertical displacement and tsunami inundation depths at the coast. The source modelling software RuptGen by Babeyko (2007) was used to calculate static seabed vertical displacement resulting from earthquake slip. More than 3,600 events were selected for tsunami simulations. Deep and shallow water wave propagation is modelled using the Delft3D modelling suite, which is a state-of-the-art software developed by Deltares. The Delft3D-FLOW module is used in 2-dimensional hydrodynamic simulation settings with non-steady flow

  9. Seismically generated tsunamis.

    Science.gov (United States)

    Arcas, Diego; Segur, Harvey

    2012-04-13

    People around the world know more about tsunamis than they did 10 years ago, primarily because of two events: a tsunami on 26 December 2004 that killed more than 200,000 people around the shores of the Indian Ocean; and an earthquake and tsunami off the coast of Japan on 11 March 2011 that killed nearly 15,000 more and triggered a nuclear accident, with consequences that are still unfolding. This paper has three objectives: (i) to summarize our current knowledge of the dynamics of tsunamis; (ii) to describe how that knowledge is now being used to forecast tsunamis; and (iii) to suggest some policy changes that might protect people better from the dangers of future tsunamis.

  10. Chile Earthquake: U.S. and International Response

    Science.gov (United States)

    2010-03-11

    most regions far from the epicenter did not experience any serious damage. A tsunami caused significant damage to the city of Hilo , Hawaii ...Tsunami Warning Center for Hawaii , Japan, and other regions bordering the Pacific Ocean that may have been vulnerable to a damaging tsunami, although...earthquake. Why the 1960 earthquake generated a tsunami that caused damage and fatalities in Hawaii , Japan, and the Philippines while the 2010 earthquake did

  11. The possibility of a tsunami on Lake Baikal

    Science.gov (United States)

    Klyuchevskii, A. V.; Demyanovich, V. M.; Klyuchevskaya, A. A.

    2012-01-01

    Based on the general physical nature of tsunami generation, it is established that it is an attribute of seismically hazardous areas and regions adjacent to large water reservoirs and is threatening to the population and infrastructure of the coastal zones. The main preconditions and possibilities for the occurrence of tsunami on Lake Baikal are considered: the information on earthquakes in the Baikal hollow during the instrumental-historical period (1724-2011) is generalized in the map of epicenters of shocks of magnitude M ⩾ 5 and histograms of the distribution of numbers of shocks with respect to magnitude. It is shown that the tsunami waves start forming on Baikal if the earthquake magnitude M is ≈5, but since a system of tsunami monitoring on Baikal is absent, it can be observed only during the strongest earthquakes of M > 7. The catastrophic Tsagan earthquake (1861, M ≈ 7.5) is given as an example. It happened near the eastern coast of Lake Baikal and caused a tsunami with people's deaths.

  12. Tsunamis

    Science.gov (United States)

    ... created by an underwater disturbance. Causes include earthquakes, landslides, volcanic eruptions, or meteorites--chunks of rock from space that strike the surface of Earth. A tsunami can move hundreds of miles per ...

  13. NATURAL HAZARD ASSESSMENT OF SW MYANMAR - A CONTRIBUTION OF REMOTE SENSING AND GIS METHODS TO THE DETECTION OF AREAS VULNERABLE TO EARTHQUAKES AND TSUNAMI / CYCLONE FLOODING

    Directory of Open Access Journals (Sweden)

    George Pararas-Carayannis

    2009-01-01

    Full Text Available Myanmar, formerly Burma, is vulnerable to several natural hazards, such as earthquakes, cyclones, floods, tsunamis and landslides. The present study focuses on geomorphologic and geologic investigations of the south-western region of the country, based on satellite data (Shuttle Radar Topography Mission-SRTM, MODIS and LANDSAT. The main objective is to detect areas vulnerable to inundation by tsunami waves and cyclone surges. Since the region is also vulnerable to earthquake hazards, it is also important to identify seismotectonic patterns, the location of major active faults, and local site conditions that may enhance ground motions and earthquake intensities. As illustrated by this study, linear, topographic features related to subsurface tectonic features become clearly visible on SRTM-derived morphometric maps and on LANDSAT imagery. The GIS integrated evaluation of LANDSAT and SRTM data helps identify areas most susceptible to flooding and inundation by tsunamis and storm surges. Additionally, land elevation maps help identify sites greater than 10 m in elevation height, that would be suitable for the building of protective tsunami/cyclone shelters.

  14. Joko Tingkir program for estimating tsunami potential rapidly

    Energy Technology Data Exchange (ETDEWEB)

    Madlazim,, E-mail: m-lazim@physics.its.ac.id; Hariyono, E., E-mail: m-lazim@physics.its.ac.id [Department of Physics, Faculty of Mathematics and Natural Sciences, Universitas Negeri Surabaya (UNESA) , Jl. Ketintang, Surabaya 60231 (Indonesia)

    2014-09-25

    The purpose of the study was to estimate P-wave rupture durations (T{sub dur}), dominant periods (T{sub d}) and exceeds duration (T{sub 50Ex}) simultaneously for local events, shallow earthquakes which occurred off the coast of Indonesia. Although the all earthquakes had parameters of magnitude more than 6,3 and depth less than 70 km, part of the earthquakes generated a tsunami while the other events (Mw=7.8) did not. Analysis using Joko Tingkir of the above stated parameters helped understand the tsunami generation of these earthquakes. Measurements from vertical component broadband P-wave quake velocity records and determination of the above stated parameters can provide a direct procedure for assessing rapidly the potential for tsunami generation. The results of the present study and the analysis of the seismic parameters helped explain why the events generated a tsunami, while the others did not.

  15. Tsunami Evidence in South Coast Java, Case Study: Tsunami Deposit along South Coast of Cilacap

    Science.gov (United States)

    Rizal, Yan; Aswan; Zaim, Yahdi; Dwijo Santoso, Wahyu; Rochim, Nur; Daryono; Dewi Anugrah, Suci; Wijayanto; Gunawan, Indra; Yatimantoro, Tatok; Hidayanti; Herdiyani Rahayu, Resti; Priyobudi

    2017-06-01

    Cilacap Area is situated in coastal area of Southern Java and directly affected by tsunami hazard in 2006. This event was triggered by active subduction in Java Trench which active since long time ago. To detect tsunami and active tectonic in Southern Java, paleo-tsunami study is performed which is targeted paleo-tsunami deposit older than fifty years ago. During 2011 - 2016, 16 locations which suspected as paleo-tsunami location were visited and the test-pits were performed to obtain characteristic and stratigraphy of paleo-tsunami layers. Paleo-tsunami layer was identified by the presence of light-sand in the upper part of paleo-soil, liquefaction fine grain sandstone, and many rip-up clast of mudstone. The systematic samples were taken and analysis (micro-fauna, grainsize and dating analysis). Micro-fauna result shows that paleo-tsunami layer consist of benthonic foraminifera assemblages from different bathymetry and mixing in one layer. Moreover, grainsize shows random grain distribution which characterized as turbulence and strong wave deposit. Paleo-tsunami layers in Cilacap area are correlated using paleo-soil as marker. There are three paleo-tsunami layers and the distribution can be identified as PS-A, PS-B and PS-C. The samples which were taken in Glempang Pasir layer are being dated using Pb - Zn (Lead-Zinc) method. The result of Pb - Zn (Lead-Zinc) dating shows that PS-A was deposited in 139 years ago, PS-B in 21 years ago, and PS C in 10 years ago. This result indicates that PS -1 occurred in 1883 earthquake activity while PS B formed in 1982 earthquake and PS-C was formed by 2006 earthquake. For ongoing research, the older paleo-tsunami layers were determined in the Gua Nagaraja, close to Selok location and 6 layers of Paleo-tsunami suspect found which shown a similar characteristic with the layers from another location. The three layers deeper approximately have an older age than another location in Cilacap.

  16. Data- and Tool-rich Curriculum on Natural Catastrophes: Case Study of M9+ Earthquakes and Mega-tsunamis in Cascadia

    Science.gov (United States)

    Mayhew, M.; Hall, M.; Walker, C. S.; Butler, R. F.

    2008-12-01

    We report on one of four undergraduate curriculum units on natural catastrophes that make use of a wide range of geologic and geophysical data sets and data visualization and analysis tools. All units use My World GIS tools, Google Earth, Excel, animations, and video. In the Cascadia case study, students conduct a series of investigations concerning evidence of M9+ earthquakes in the past and evidence of present-day deformation consistent with the likelihood of another such earthquake some time in the future. The unit begins with Native oral traditions that predate European settlement of the region in the mid-18th century that tell of a huge earthquake and accompanying tsunami. The scene shifts to the great M9+ Sumatra earthquake of 2004 as a possible analog. Students analyze GPS and other data related to horizontal and vertical motions accompanying the earthquake. Comparisons of deformation patterns and rupture zone extent among the 2004 M9+ Sumatran, 1960 M9+ Chilean and the 1964 M9+ Alaskan earthquakes are made with a possible Cascadian analog. Students analyze Cascadia GPS data from the Plate Boundary Observatory and investigate strain accumulation patterns consistent with a locked zone at the shallow part of the subduction zone. They then use geologic evidence to evaluate the possibility of great earthquakes in the past. They do this much in the same way that geologists have, noting the distinctive stratigraphic evidence of catastrophic subsidence and tsunami inundation, directly analogous to the effects accompanying the other great earthquakes they have studied. They determine the year, date, and time of the last great earthquake that occurred here, by linking to the Japanese historical record of an "Orphan Tsunami" that devastated Japan in 1700. They note evidence from coastal estuarian stratigraphy and from deep sea cores in the Cascadia Basin of multiple great earthquakes over the last 10,000 years and compute recurrence intervals. They then conduct a

  17. REMOTE OPERATION OF THE WEST COAST AND ALASKA TSUNAMI WARNING CENTER

    Directory of Open Access Journals (Sweden)

    Alec H. Medbery

    2002-01-01

    Full Text Available The remote control of real time derivation of earthquake location and magnitude and the issuance of tsunami and earthquake bulletins was done using off-the-shelf remote control software and hardware. Such remote operation of the West Coast/Alaska Tsunami Warning Center can decrease the time needed to respond to an earthquake by eliminating travel from the duty standers’ home to the tsunami warning center.

  18. Synthetic tsunami waveform catalogs with kinematic constraints

    Science.gov (United States)

    Baptista, Maria Ana; Miranda, Jorge Miguel; Matias, Luis; Omira, Rachid

    2017-07-01

    In this study we present a comprehensive methodology to produce a synthetic tsunami waveform catalogue in the northeast Atlantic, east of the Azores islands. The method uses a synthetic earthquake catalogue compatible with plate kinematic constraints of the area. We use it to assess the tsunami hazard from the transcurrent boundary located between Iberia and the Azores, whose western part is known as the Gloria Fault. This study focuses only on earthquake-generated tsunamis. Moreover, we assume that the time and space distribution of the seismic events is known. To do this, we compute a synthetic earthquake catalogue including all fault parameters needed to characterize the seafloor deformation covering the time span of 20 000 years, which we consider long enough to ensure the representability of earthquake generation on this segment of the plate boundary. The computed time and space rupture distributions are made compatible with global kinematic plate models. We use the tsunami empirical Green's functions to efficiently compute the synthetic tsunami waveforms for the dataset of coastal locations, thus providing the basis for tsunami impact characterization. We present the results in the form of offshore wave heights for all coastal points in the dataset. Our results focus on the northeast Atlantic basin, showing that earthquake-induced tsunamis in the transcurrent segment of the Azores-Gibraltar plate boundary pose a minor threat to coastal areas north of Portugal and beyond the Strait of Gibraltar. However, in Morocco, the Azores, and the Madeira islands, we can expect wave heights between 0.6 and 0.8 m, leading to precautionary evacuation of coastal areas. The advantages of the method are its easy application to other regions and the low computation effort needed.

  19. Peru 2007 tsunami runup observations and modeling

    Science.gov (United States)

    Fritz, H. M.; Kalligeris, N.; Borrero, J. C.

    2008-05-01

    On 15 August 2007 an earthquake with moment magnitude (Mw) of 8.0 centered off the coast of central Peru, generated a tsunami with locally focused runup heights of up to 10 m. A reconnaissance team was deployed in the immediate aftermath and investigated the tsunami effects at 51 sites. The largest runup heights were measured in a sparsely populated desert area south of the Paracas Peninsula resulting in only 3 tsunami fatalities. Numerical modeling of the earthquake source and tsunami suggest that a region of high slip near the coastline was primarily responsible for the extreme runup heights. The town of Pisco was spared by the presence of the Paracas Peninsula, which blocked tsunami waves from propagating northward from the high slip region. The coast of Peru has experienced numerous deadly and destructive tsunamis throughout history, which highlights the importance of ongoing tsunami awareness and education efforts in the region. The Peru tsunami is compared against recent mega-disasters such as the 2004 Indian Ocean tsunami and Hurricane Katrina.

  20. Impacts of the June 23, 2001 Peru Tsunami

    Science.gov (United States)

    Dengler, L.

    2001-12-01

    The tsunami generated by the June 23, 2001 Peru earthquake caused significant damage to a 20-km long stretch of coastline in the Municipality of Camana, southern Peru. Over 3000 structures were damaged or destroyed and 2000 hectares of farmland flooded and covered with sand. 22 people were killed in the Municipality and 62 were reported missing. All of the casualties were attributed to the tsunami; in Camana the earthquake produced Modified Mercalli Intensities only of VI or VII. The International Tsunami Survey Team (ITST) were in Peru July 5 - 15 and measured inundation, spoke with City, Red Cross, and Health Department officials, and interviewed survivors. The preliminary ITST findings: All eyewitnesses described an initial draw-down that lasted a substantial amount of time (15 minutes or more). The initial positive wave was small, followed by two destructive waves of near similar impact. Observing the water recede was the key to self-evacuation. No one responded to the ground shaking even though all felt the earthquake strongly. Damage was concentrated along a flat coastal beach no higher than 5 m above sea level. The largest waves (5 to 8 meters) produced by this tsunami coincided with the most developed beach area along the southern Peruvian coast. Tsunami waves penetrated 1.2-km inland and damaged or destroyed nearly all of the structures in this zone. Poorly built adobe and infilled wall structures performed very poorly in the tsunami impacted area. The few structures that survived appeared to have deeper foundations and more reinforcing. The most tsunami-vulnerable populations were newcomers to the coast. Most victims were farm workers and domestic summerhouse sitters who had not grown up along the coast and were unaware of tsunami hazards. Economic impacts are likely to last a long time. The main industries in Camana are tourism and agriculture and the tsunami damaged both. While the extent of inundation and the number of structures damaged or destroyed

  1. Constraining the Source of the M w 8.1 Chiapas, Mexico Earthquake of 8 September 2017 Using Teleseismic and Tsunami Observations

    Science.gov (United States)

    Heidarzadeh, Mohammad; Ishibe, Takeo; Harada, Tomoya

    2018-04-01

    The September 2017 Chiapas (Mexico) normal-faulting intraplate earthquake (M w 8.1) occurred within the Tehuantepec seismic gap offshore Mexico. We constrained the finite-fault slip model of this great earthquake using teleseismic and tsunami observations. First, teleseismic body-wave inversions were conducted for both steep (NP-1) and low-angle (NP-2) nodal planes for rupture velocities (V r) of 1.5-4.0 km/s. Teleseismic inversion guided us to NP-1 as the actual fault plane, but was not conclusive about the best V r. Tsunami simulations also confirmed that NP-1 is favored over NP-2 and guided the V r = 2.5 km/s as the best source model. Our model has a maximum and average slips of 13.1 and 3.7 m, respectively, over a 130 km × 80 km fault plane. Coulomb stress transfer analysis revealed that the probability for the occurrence of a future large thrust interplate earthquake at offshore of the Tehuantepec seismic gap had been increased following the 2017 Chiapas normal-faulting intraplate earthquake.

  2. Tsunami hazard

    International Nuclear Information System (INIS)

    2013-01-01

    Tohoku Earthquake Tsunami on 11 March, 2011 has led the Fukushima Daiichi nuclear power plant to a serious accident, which highlighted a variety of technical issues such as a very low design tsunami height and insufficient preparations in case a tsunami exceeding the design tsunami height. Lessons such as to take measures to be able to maintain the important safety features of the facility for tsunamis exceeding design height and to implement risk management utilizing Probabilistic Safety Assessment are shown. In order to implement the safety assessment on nuclear power plants across Japan accordingly to the back-fit rule, Nuclear Regulatory Commission will promulgate/execute the New Safety Design Criteria in July 2013. JNES has positioned the 'enhancement of probabilistic tsunami hazard assessment' as highest priority issue and implemented in order to support technically the Nuclear Regulatory Authority in formulating the new Safety Design Criteria. Findings of the research had reflected in the 'Technical Review Guidelines for Assessing Design Tsunami Height based on tsunami hazards'. (author)

  3. Relationship between the Prediction Accuracy of Tsunami Inundation and Relative Distribution of Tsunami Source and Observation Arrays: A Case Study in Tokyo Bay

    Science.gov (United States)

    Takagawa, T.

    2017-12-01

    A rapid and precise tsunami forecast based on offshore monitoring is getting attention to reduce human losses due to devastating tsunami inundation. We developed a forecast method based on the combination of hierarchical Bayesian inversion with pre-computed database and rapid post-computing of tsunami inundation. The method was applied to Tokyo bay to evaluate the efficiency of observation arrays against three tsunamigenic earthquakes. One is a scenario earthquake at Nankai trough and the other two are historic ones of Genroku in 1703 and Enpo in 1677. In general, rich observation array near the tsunami source has an advantage in both accuracy and rapidness of tsunami forecast. To examine the effect of observation time length we used four types of data with the lengths of 5, 10, 20 and 45 minutes after the earthquake occurrences. Prediction accuracy of tsunami inundation was evaluated by the simulated tsunami inundation areas around Tokyo bay due to target earthquakes. The shortest time length of accurate prediction varied with target earthquakes. Here, accurate prediction means the simulated values fall within the 95% credible intervals of prediction. In Enpo earthquake case, 5-minutes observation is enough for accurate prediction for Tokyo bay, but 10-minutes and 45-minutes are needed in the case of Nankai trough and Genroku, respectively. The difference of the shortest time length for accurate prediction shows the strong relationship with the relative distance from the tsunami source and observation arrays. In the Enpo case, offshore tsunami observation points are densely distributed even in the source region. So, accurate prediction can be rapidly achieved within 5 minutes. This precise prediction is useful for early warnings. Even in the worst case of Genroku, where less observation points are available near the source, accurate prediction can be obtained within 45 minutes. This information can be useful to figure out the outline of the hazard in an early

  4. Interseismic Coupling-Based Earthquake and Tsunami Scenarios for the Nankai Trough

    Science.gov (United States)

    Baranes, H.; Woodruff, J. D.; Loveless, J. P.; Hyodo, M.

    2018-04-01

    Theoretical modeling and investigations of recent subduction zone earthquakes show that geodetic estimates of interseismic coupling and the spatial distribution of coseismic rupture are correlated. However, the utility of contemporary coupling in guiding construction of rupture scenarios has not been evaluated on the world's most hazardous faults. Here we demonstrate methods for scaling coupling to slip to create rupture models for southwestern Japan's Nankai Trough. Results show that coupling-based models produce distributions of ground surface deformation and tsunami inundation that are similar to historical and geologic records of the largest known Nankai earthquake in CE 1707 and to an independent, quasi-dynamic rupture model. Notably, these models and records all support focused subsidence around western Shikoku that makes the region particularly vulnerable to flooding. Results imply that contemporary coupling mirrors the slip distribution of a full-margin, 1707-type rupture, and Global Positioning System measurements of surface motion are connected with the trough's physical characteristics.

  5. Mega Tsunamis of the World Ocean and Their Implication for the Tsunami Hazard Assessment

    Science.gov (United States)

    Gusiakov, V. K.

    2014-12-01

    Mega tsunamis are the strongest tsunamigenic events of tectonic origin that are characterized by run-up heights up to 40-50 m measured along a considerable part of the coastline (up to 1000 km). One of the most important features of mega-tsunamis is their ability to cross the entire oceanic basin and to cause an essential damage to its opposite coast. Another important feature is their ability to penetrate into the marginal seas (like the Sea of Okhotsk, the Bering Sea) and cause dangerous water level oscillations along the parts of the coast, which are largely protected by island arcs against the impact of the strongest regional tsunamis. Among all known historical tsunamis (nearly 2250 events during the last 4000 years) they represent only a small fraction (less than 1%) however they are responsible for more than half the total tsunami fatalities and a considerable part of the overall tsunami damage. The source of all known mega tsunamis is subduction submarine earthquakes with magnitude 9.0 or higher having a return period from 200-300 years to 1000-1200 years. The paper presents a list of 15 mega tsunami events identified so far in historical catalogs with their basic source parameters, near-field and far-field impact effects and their generation and propagation features. The far-field impact of mega tsunamis is largely controlled by location and orientation of their earthquake source as well as by deep ocean bathymetry features. We also discuss the problem of the long-term tsunami hazard assessment when the occurrence of mega tsunamis is taken into account.

  6. Tsunami Loss Assessment For Istanbul

    Science.gov (United States)

    Hancilar, Ufuk; Cakti, Eser; Zulfikar, Can; Demircioglu, Mine; Erdik, Mustafa

    2010-05-01

    Tsunami risk and loss assessment incorporating with the inundation mapping in Istanbul and the Marmara Sea region are presented in this study. The city of Istanbul is under the threat of earthquakes expected to originate from the Main Marmara branch of North Anatolian Fault System. In the Marmara region the earthquake hazard reached very high levels with 2% annual probability of occurrence of a magnitude 7+ earthquake on the Main Marmara Fault. Istanbul is the biggest city of Marmara region as well as of Turkey with its almost 12 million inhabitants. It is home to 40% of the industrial facilities in Turkey and operates as the financial and trade hub of the country. Past earthquakes have evidenced that the structural reliability of residential and industrial buildings, as well as that of lifelines including port and harbor structures in the country is questionable. These facts make the management of earthquake risks imperative for the reduction of physical and socio-economic losses. The level of expected tsunami hazard in Istanbul is low as compared to earthquake hazard. Yet the assets at risk along the shores of the city make a thorough assessment of tsunami risk imperative. Important residential and industrial centres exist along the shores of the Marmara Sea. Particularly along the northern and eastern shores we see an uninterrupted settlement pattern with industries, businesses, commercial centres and ports and harbours in between. Following the inundation maps resulting from deterministic and probabilistic tsunami hazard analyses, vulnerability and risk analyses are presented and the socio-economic losses are estimated. This study is part of EU-supported FP6 project ‘TRANSFER'.

  7. Tsunami risk mapping simulation for Malaysia

    Science.gov (United States)

    Teh, S.Y.; Koh, H. L.; Moh, Y.T.; De Angelis, D. L.; Jiang, J.

    2011-01-01

    The 26 December 2004 Andaman mega tsunami killed about a quarter of a million people worldwide. Since then several significant tsunamis have recurred in this region, including the most recent 25 October 2010 Mentawai tsunami. These tsunamis grimly remind us of the devastating destruction that a tsunami might inflict on the affected coastal communities. There is evidence that tsunamis of similar or higher magnitudes might occur again in the near future in this region. Of particular concern to Malaysia are tsunamigenic earthquakes occurring along the northern part of the Sunda Trench. Further, the Manila Trench in the South China Sea has been identified as another source of potential tsunamigenic earthquakes that might trigger large tsunamis. To protect coastal communities that might be affected by future tsunamis, an effective early warning system must be properly installed and maintained to provide adequate time for residents to be evacuated from risk zones. Affected communities must be prepared and educated in advance regarding tsunami risk zones, evacuation routes as well as an effective evacuation procedure that must be taken during a tsunami occurrence. For these purposes, tsunami risk zones must be identified and classified according to the levels of risk simulated. This paper presents an analysis of tsunami simulations for the South China Sea and the Andaman Sea for the purpose of developing a tsunami risk zone classification map for Malaysia based upon simulated maximum wave heights. ?? 2011 WIT Press.

  8. Tsunami in the Arctic

    Science.gov (United States)

    Kulikov, Evgueni; Medvedev, Igor; Ivaschenko, Alexey

    2017-04-01

    The severity of the climate and sparsely populated coastal regions are the reason why the Russian part of the Arctic Ocean belongs to the least studied areas of the World Ocean. In the same time intensive economic development of the Arctic region, specifically oil and gas industry, require studies of potential thread natural disasters that can cause environmental and technical damage of the coastal and maritime infrastructure of energy industry complex (FEC). Despite the fact that the seismic activity in the Arctic can be attributed to a moderate level, we cannot exclude the occurrence of destructive tsunami waves, directly threatening the FEC. According to the IAEA requirements, in the construction of nuclear power plants it is necessary to take into account the impact of all natural disasters with frequency more than 10-5 per year. Planned accommodation in the polar regions of the Russian floating nuclear power plants certainly requires an adequate risk assessment of the tsunami hazard in the areas of their location. Develop the concept of tsunami hazard assessment would be based on the numerical simulation of different scenarios in which reproduced the hypothetical seismic sources and generated tsunamis. The analysis of available geological, geophysical and seismological data for the period of instrumental observations (1918-2015) shows that the highest earthquake potential within the Arctic region is associated with the underwater Mid-Arctic zone of ocean bottom spreading (interplate boundary between Eurasia and North American plates) as well as with some areas of continental slope within the marginal seas. For the Arctic coast of Russia and the adjacent shelf area, the greatest tsunami danger of seismotectonic origin comes from the earthquakes occurring in the underwater Gakkel Ridge zone, the north-eastern part of the Mid-Arctic zone. In this area, one may expect earthquakes of magnitude Mw ˜ 6.5-7.0 at a rate of 10-2 per year and of magnitude Mw ˜ 7.5 at a

  9. Evaluation of tsunami risk in the Lesser Antilles

    Directory of Open Access Journals (Sweden)

    N. Zahibo

    2001-01-01

    Full Text Available The main goal of this study is to give the preliminary estimates of the tsunami risks for the Lesser Antilles. We investigated the available data of the tsunamis in the French West Indies using the historical data and catalogue of the tsunamis in the Lesser Antilles. In total, twenty-four (24 tsunamis were recorded in this area for last 400 years; sixteen (16 events of the seismic origin, five (5 events of volcanic origin and three (3 events of unknown source. Most of the tsunamigenic earthquakes (13 occurred in the Caribbean, and three tsunamis were generated during far away earthquakes (near the coasts of Portugal and Costa Rica. The estimates of tsunami risk are based on a preliminary analysis of the seismicity of the Caribbean area and the historical data of tsunamis. In particular, we investigate the occurrence of historical extreme runup tsunami data on Guadeloupe, and these data are revised after a survey in Guadeloupe.

  10. The Boxing Day Tsunami: Could the Disaster have been Anticipated?

    Science.gov (United States)

    Cummins, P. R.; Burbdige, D.

    2005-05-01

    The occurrence of the 26 December, 2004 Sumatra-Andaman earthquake and the accompanying "Boxing Day" Tsunami, which killed over 280,00, has been described as one of the most lethal natural disasters in human history. Many lives could have been saved had a tsunami warning system, similar to that which exists for the Pacific Ocean, been in operation for the Indian Ocean. The former exists because great subduction zone earthquakes have generated destructive, Pacific-wide tsunami in the Pacific Ocean with some frequency. Prior to 26 December, 2004, all of the world's earthquakes with magnitude > 9 were widely thought to have occurred in the Pacific Ocean, where they caused destructive tsunami. Could the occurrence of similar earthquakes and tsunami in the Indian Ocean been predicted prior to the 2004 Box Day Tragedy? This presentation will argue that the answer is "Yes". Almost without exception (the exception being the 1952 Kamchatka earthquake) the massive subduction zone earthquakes and tsunami of the Pacific Ocean have been associated with the subduction of relatively young ocean lithosphere (Boxing day event, the effects in the Bay of Bengal would not have been as severe. Thus, it seems to this author that the Boxing Day event could and should have been anticipated. This presentation will further consider why it was not, and what steps can be taken to anticipate and mitigate the effects of future events that may occur in the Indian Ocean and elsewhere.

  11. Structural control on the Tohoku earthquake rupture process investigated by 3D FEM, tsunami and geodetic data.

    Science.gov (United States)

    Romano, F; Trasatti, E; Lorito, S; Piromallo, C; Piatanesi, A; Ito, Y; Zhao, D; Hirata, K; Lanucara, P; Cocco, M

    2014-07-09

    The 2011 Tohoku earthquake (Mw = 9.1) highlighted previously unobserved features for megathrust events, such as the large slip in a relatively limited area and the shallow rupture propagation. We use a Finite Element Model (FEM), taking into account the 3D geometrical and structural complexities up to the trench zone, and perform a joint inversion of tsunami and geodetic data to retrieve the earthquake slip distribution. We obtain a close spatial correlation between the main deep slip patch and the local seismic velocity anomalies, and large shallow slip extending also to the North coherently with a seismically observed low-frequency radiation. These observations suggest that the friction controlled the rupture, initially confining the deeper rupture and then driving its propagation up to the trench, where it spreads laterally. These findings are relevant to earthquake and tsunami hazard assessment because they may help to detect regions likely prone to rupture along the megathrust, and to constrain the probability of high slip near the trench. Our estimate of ~40 m slip value around the JFAST (Japan Trench Fast Drilling Project) drilling zone contributes to constrain the dynamic shear stress and friction coefficient of the fault obtained by temperature measurements to ~0.68 MPa and ~0.10, respectively.

  12. Application of Seismic Array Processing to Tsunami Early Warning

    Science.gov (United States)

    An, C.; Meng, L.

    2015-12-01

    Tsunami wave predictions of the current tsunami warning systems rely on accurate earthquake source inversions of wave height data. They are of limited effectiveness for the near-field areas since the tsunami waves arrive before data are collected. Recent seismic and tsunami disasters have revealed the need for early warning to protect near-source coastal populations. In this work we developed the basis for a tsunami warning system based on rapid earthquake source characterisation through regional seismic array back-projections. We explored rapid earthquake source imaging using onshore dense seismic arrays located at regional distances on the order of 1000 km, which provides faster source images than conventional teleseismic back-projections. We implement this method in a simulated real-time environment, and analysed the 2011 Tohoku earthquake rupture with two clusters of Hi-net stations in Kyushu and Northern Hokkaido, and the 2014 Iquique event with the Earthscope USArray Transportable Array. The results yield reasonable estimates of rupture area, which is approximated by an ellipse and leads to the construction of simple slip models based on empirical scaling of the rupture area, seismic moment and average slip. The slip model is then used as the input of the tsunami simulation package COMCOT to predict the tsunami waves. In the example of the Tohoku event, the earthquake source model can be acquired within 6 minutes from the start of rupture and the simulation of tsunami waves takes less than 2 min, which could facilitate a timely tsunami warning. The predicted arrival time and wave amplitude reasonably fit observations. Based on this method, we propose to develop an automatic warning mechanism that provides rapid near-field warning for areas of high tsunami risk. The initial focus will be Japan, Pacific Northwest and Alaska, where dense seismic networks with the capability of real-time data telemetry and open data accessibility, such as the Japanese HiNet (>800

  13. ESTIMATION OF DAMAGED AREAS DUE TO THE 2010 CHILE EARTHQUAKE AND TSUNAMI USING SAR IMAGERY OF ALOS/PALSAR

    Directory of Open Access Journals (Sweden)

    P. J. Ni Made

    2016-06-01

    Full Text Available A large-scale earthquake and tsunami affect thousands of people and cause serious damages worldwide every year. Quick observation of the disaster damage is extremely important for planning effective rescue operations. In the past, acquiring damage information was limited to only field surveys or using aerial photographs. In the last decade, space-borne images were used in many disaster researches, such as tsunami damage detection. In this study, SAR data of ALOS/PALSAR satellite images were used to estimate tsunami damage in the form of inundation areas in Talcahuano, the area near the epicentre of the 2010 Chile earthquake. The image processing consisted of three stages, i.e. pre-processing, analysis processing, and post-processing. It was conducted using multi-temporal images before and after the disaster. In the analysis processing, inundation areas were extracted through the masking processing. It consisted of water masking using a high-resolution optical image of ALOS/AVNIR-2 and elevation masking which built upon the inundation height using DEM image of ASTER-GDEM. The area result was 8.77 Km2. It showed a good result and corresponded to the inundation map of Talcahuano. Future study in another area is needed in order to strengthen the estimation processing method.

  14. September 2009 Samoa Islands, Samoa Images

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — At least 149 people killed in Samoa, 34 killed in American Samoa and 9 killed, 7 injured and 500 displaced on Niuatoputapu, Tonga. Widespread damage to...

  15. Did a submarine landslide contribute to the 2011 Tohoku tsunami?

    KAUST Repository

    Tappin, David R.

    2014-09-28

    Many studies have modeled the Tohoku tsunami of March 11, 2011 as being due entirely to slip on an earthquake fault, but the following discrepancies suggest that further research is warranted. (1) Published models of tsunami propagation and coastal impact underpredict the observed runup heights of up to 40 m measured along the coast of the Sanriku district in the northeast part of Honshu Island. (2) Published models cannot reproduce the timing and high-frequency content of tsunami waves recorded at three nearshore buoys off Sanriku, nor the timing and dispersion properties of the waveforms at offshore DART buoy #21418. (3) The rupture centroids obtained by tsunami inversions are biased about 60 km NNE of that obtained by the Global CMT Project. Based on an analysis of seismic and geodetic data, together with recorded tsunami waveforms, we propose that, while the primary source of the tsunami was the vertical displacement of the seafloor due to the earthquake, an additional tsunami source is also required. We infer the location of the proposed additional source based on an analysis of the travel times of higher-frequency tsunami waves observed at nearshore buoys. We further propose that the most likely additional tsunami source was a submarine mass failure (SMF—i.e., a submarine landslide). A comparison of pre- and post-tsunami bathymetric surveys reveals tens of meters of vertical seafloor movement at the proposed SMF location, and a slope stability analysis confirms that the horizontal acceleration from the earthquake was sufficient to trigger an SMF. Forward modeling of the tsunami generated by a combination of the earthquake and the SMF reproduces the recorded on-, near- and offshore tsunami observations well, particularly the high-frequency component of the tsunami waves off Sanriku, which were not well simulated by previous models. The conclusion that a significant part of the 2011 Tohoku tsunami was generated by an SMF source has important implications for

  16. Development of Real-time Tsunami Inundation Forecast Using Ocean Bottom Tsunami Networks along the Japan Trench

    Science.gov (United States)

    Aoi, S.; Yamamoto, N.; Suzuki, W.; Hirata, K.; Nakamura, H.; Kunugi, T.; Kubo, T.; Maeda, T.

    2015-12-01

    In the 2011 Tohoku earthquake, in which huge tsunami claimed a great deal of lives, the initial tsunami forecast based on hypocenter information estimated using seismic data on land were greatly underestimated. From this lesson, NIED is now constructing S-net (Seafloor Observation Network for Earthquakes and Tsunamis along the Japan Trench) which consists of 150 ocean bottom observatories with seismometers and pressure gauges (tsunamimeters) linked by fiber optic cables. To take full advantage of S-net, we develop a new methodology of real-time tsunami inundation forecast using ocean bottom observation data and construct a prototype system that implements the developed forecasting method for the Pacific coast of Chiba prefecture (Sotobo area). We employ a database-based approach because inundation is a strongly non-linear phenomenon and its calculation costs are rather heavy. We prepare tsunami scenario bank in advance, by constructing the possible tsunami sources, and calculating the tsunami waveforms at S-net stations, coastal tsunami heights and tsunami inundation on land. To calculate the inundation for target Sotobo area, we construct the 10-m-mesh precise elevation model with coastal structures. Based on the sensitivities analyses, we construct the tsunami scenario bank that efficiently covers possible tsunami scenarios affecting the Sotobo area. A real-time forecast is carried out by selecting several possible scenarios which can well explain real-time tsunami data observed at S-net from tsunami scenario bank. An advantage of our method is that tsunami inundations are estimated directly from the actual tsunami data without any source information, which may have large estimation errors. In addition to the forecast system, we develop Web services, APIs, and smartphone applications and brush them up through social experiments to provide the real-time tsunami observation and forecast information in easy way to understand toward urging people to evacuate.

  17. Tsunamis from strike-slip earthquakes in the Wharton Basin, northeast Indian Ocean: March 2016 Mw7.8 event and its relationship with the April 2012 Mw 8.6 event

    Science.gov (United States)

    Heidarzadeh, Mohammad; Harada, Tomoya; Satake, Kenji; Ishibe, Takeo; Takagawa, Tomohiro

    2017-12-01

    The Wharton Basin, off southwest Sumatra, ruptured to a large intraplate left-lateral strike-slip Mw 7.8 earthquake on 2016 March 2. The epicentre was located ∼800 km to the south of another similar-mechanism intraplate Mw 8.6 earthquake in the same basin on 2012 April 11. Small tsunamis from these strike-slip earthquakes were registered with maximum amplitudes of 0.5-1.5 cm on DARTs and 1-19 cm on tide gauges for the 2016 event, and the respective values of 0.5-6 and 6-40 cm for the 2012 event. By using both teleseismic body waves and tsunami observations of the 2016 event, we obtained optimum slip models with rupture velocity (Vr) in the range of 2.8-3.6 km s-1 belonging to both EW and NS faults. While the EW fault plane cannot be fully ruled out, we chose the best model as the NS fault plane with a Vr of 3.6 km s-1, a maximum slip of 7.7 m and source duration of 33 s. The tsunami energy period bands were 4-15 and 7-24 min for the 2016 and 2012 tsunamis, respectively, reflecting the difference in source sizes. Seismicity in the Wharton Basin is dominated by large strike-slip events including the 2012 (Mw 8.6 and 8.2) and 2016 (Mw 7.8) events, indicating that these events are possible tsunami sources in the Wharton Basin. Cumulative number and cumulative seismic-moment curves revealed that most earthquakes are of strike-slip mechanisms and the largest seismic-moment is provided by the strike-slip earthquakes in this basin.

  18. Introduction to "Tsunamis in the Pacific Ocean: 2011-2012"

    Science.gov (United States)

    Rabinovich, Alexander B.; Borrero, Jose C.; Fritz, Hermann M.

    2014-12-01

    With this volume of the Pure and Applied Geophysics (PAGEOPH) topical issue "Tsunamis in the Pacific Ocean: 2011-2012", we are pleased to present 21 new papers discussing tsunami events occurring in this two-year span. Owing to the profound impact resulting from the unique crossover of a natural and nuclear disaster, research into the 11 March 2011 Tohoku, Japan earthquake and tsunami continues; here we present 12 papers related to this event. Three papers report on detailed field survey results and updated analyses of the wave dynamics based on these surveys. Two papers explore the effects of the Tohoku tsunami on the coast of Russia. Three papers discuss the tsunami source mechanism, and four papers deal with tsunami hydrodynamics in the far field or over the wider Pacific basin. In addition, a series of five papers presents studies of four new tsunami and earthquake events occurring over this time period. This includes tsunamis in El Salvador, the Philippines, Japan and the west coast of British Columbia, Canada. Finally, we present four new papers on tsunami science, including discussions on tsunami event duration, tsunami wave amplitude, tsunami energy and tsunami recurrence.

  19. Preliminary Hazard Assessment for Tectonic Tsunamis in the Eastern Mediterranean

    Science.gov (United States)

    Aydin, B.; Bayazitoglu, O.; Sharghi vand, N.; Kanoglu, U.

    2017-12-01

    There are many critical industrial facilities such as energy production units and energy transmission lines along the southeast coast of Turkey. This region is also active on tourism, and agriculture and aquaculture production. There are active faults in the region, i.e. the Cyprus Fault, which extends along the Mediterranean basin in the east-west direction and connects to the Hellenic Arc. Both the Cyprus Fault and the Hellenic Arc are seismologically active and are capable of generating earthquakes with tsunamigenic potential. Even a small tsunami in the region could cause confusion as shown by the recent 21 July 2017 earthquake of Mw 6.6, which occurred in the Aegean Sea, between Bodrum, Turkey and Kos Island, Greece since region is not prepared for such an event. Moreover, the Mediterranean Sea is one of the most vulnerable regions against sea level rise due to global warming, according to the 5th Report of the Intergovernmental Panel on Climate Change. For these reasons, a marine hazard such as a tsunami can cause much worse damage than expected in the region (Kanoglu et al., Phil. Trans. R. Soc. A 373, 2015). Hence, tsunami hazard assessment is required for the region. In this study, we first characterize earthquakes which have potential to generate a tsunami in the Eastern Mediterranean. Such study is a prerequisite for regional tsunami mitigation studies. For fast and timely predictions, tsunami warning systems usually employ databases that store pre-computed tsunami propagation resulting from hypothetical earthquakes with pre-defined parameters. These pre-defined sources are called tsunami unit sources and they are linearly superposed to mimic a real event, since wave propagation is linear offshore. After investigating historical earthquakes along the Cyprus Fault and the Hellenic Arc, we identified tsunamigenic earthquakes in the Eastern Mediterranean and proposed tsunami unit sources for the region. We used the tsunami numerical model MOST (Titov et al

  20. Airburst-Generated Tsunamis

    Science.gov (United States)

    Berger, Marsha; Goodman, Jonathan

    2018-04-01

    This paper examines the questions of whether smaller asteroids that burst in the air over water can generate tsunamis that could pose a threat to distant locations. Such airburst-generated tsunamis are qualitatively different than the more frequently studied earthquake-generated tsunamis, and differ as well from tsunamis generated by asteroids that strike the ocean. Numerical simulations are presented using the shallow water equations in several settings, demonstrating very little tsunami threat from this scenario. A model problem with an explicit solution that demonstrates and explains the same phenomena found in the computations is analyzed. We discuss the question of whether compressibility and dispersion are important effects that should be included, and show results from a more sophisticated model problem using the linearized Euler equations that begins to addresses this.

  1. Rapid Determination of Appropriate Source Models for Tsunami Early Warning using a Depth Dependent Rigidity Curve: Method and Numerical Tests

    Science.gov (United States)

    Tanioka, Y.; Miranda, G. J. A.; Gusman, A. R.

    2017-12-01

    Recently, tsunami early warning technique has been improved using tsunami waveforms observed at the ocean bottom pressure gauges such as NOAA DART system or DONET and S-NET systems in Japan. However, for tsunami early warning of near field tsunamis, it is essential to determine appropriate source models using seismological analysis before large tsunamis hit the coast, especially for tsunami earthquakes which generated significantly large tsunamis. In this paper, we develop a technique to determine appropriate source models from which appropriate tsunami inundation along the coast can be numerically computed The technique is tested for four large earthquakes, the 1992 Nicaragua tsunami earthquake (Mw7.7), the 2001 El Salvador earthquake (Mw7.7), the 2004 El Astillero earthquake (Mw7.0), and the 2012 El Salvador-Nicaragua earthquake (Mw7.3), which occurred off Central America. In this study, fault parameters were estimated from the W-phase inversion, then the fault length and width were determined from scaling relationships. At first, the slip amount was calculated from the seismic moment with a constant rigidity of 3.5 x 10**10N/m2. The tsunami numerical simulation was carried out and compared with the observed tsunami. For the 1992 Nicaragua tsunami earthquake, the computed tsunami was much smaller than the observed one. For the 2004 El Astillero earthquake, the computed tsunami was overestimated. In order to solve this problem, we constructed a depth dependent rigidity curve, similar to suggested by Bilek and Lay (1999). The curve with a central depth estimated by the W-phase inversion was used to calculate the slip amount of the fault model. Using those new slip amounts, tsunami numerical simulation was carried out again. Then, the observed tsunami heights, run-up heights, and inundation areas for the 1992 Nicaragua tsunami earthquake were well explained by the computed one. The other tsunamis from the other three earthquakes were also reasonably well explained

  2. A review of tsunami simulation activities for NPPs safety

    International Nuclear Information System (INIS)

    Sharma, Pavan K.

    2011-01-01

    The tsunami generated on December 26, 2004 due to Sumatra earthquake of magnitude 9.3 resulted in inundation at the various coastal sites of India. The site selection and design of Indian nuclear power plants demand the evaluation of run up and the structural barriers for the coastal plants: Besides it is also desirable to evaluate the early warning system for tsunamigenic earthquakes. The tsunamis originate from submarine faults, underwater volcanic activities, sub-aerial landslides impinging on the sea and submarine landslides. In case of a submarine earthquake-induced tsunami the wave is generated in the fluid domain due to displacement of the seabed. There are three phases of tsunami: generation, propagation, and run-up. Reactor Safety Division (RSD) of Bhabha Atomic Research Centre (BARC), Trombay has initiated computational simulation for all the three phases of tsunami source generation, its propagation and finally run up evaluation for the protection of public life, property and various industrial infrastructures located on the coastal regions of India. These studies could be effectively utilized for design and implementation of early warning system for coastal region of the country apart from catering to the needs of Indian nuclear installations. This paper presents some results of tsunami waves based on finite difference numerical approaches with shallow water wave theory. The present paper evaluate the results of various simulation i.e. Single fault Sumatra model, four and five fault Sumatra Model, Nias insignificant tsunami and also some parametric studies results for tsunami waring system scenario generation. A study is carried for the tsunami due to Sumatra earthquake in 2004 with TUNAMI-N2 software. Bathymetry data available from the National Geophysical Data Center was used for this study. The single fault and detailed four and five fault data were used to calculate sea surface deformations which were subsequently used as initial conditions for

  3. Tsunami forecast by joint inversion of real-time tsunami waveforms and seismic of GPS data: application to the Tohoku 2011 tsunami

    Science.gov (United States)

    Yong, Wei; Newman, Andrew V.; Hayes, Gavin P.; Titov, Vasily V.; Tang, Liujuan

    2014-01-01

    Correctly characterizing tsunami source generation is the most critical component of modern tsunami forecasting. Although difficult to quantify directly, a tsunami source can be modeled via different methods using a variety of measurements from deep-ocean tsunameters, seismometers, GPS, and other advanced instruments, some of which in or near real time. Here we assess the performance of different source models for the destructive 11 March 2011 Japan tsunami using model–data comparison for the generation, propagation, and inundation in the near field of Japan. This comparative study of tsunami source models addresses the advantages and limitations of different real-time measurements with potential use in early tsunami warning in the near and far field. The study highlights the critical role of deep-ocean tsunami measurements and rapid validation of the approximate tsunami source for high-quality forecasting. We show that these tsunami measurements are compatible with other real-time geodetic data, and may provide more insightful understanding of tsunami generation from earthquakes, as well as from nonseismic processes such as submarine landslide failures.

  4. Near Source 2007 Peru Tsunami Runup Observations and Modeling

    Science.gov (United States)

    Borrero, J. C.; Fritz, H. M.; Kalligeris, N.; Broncano, P.; Ortega, E.

    2008-12-01

    On 15 August 2007 an earthquake with moment magnitude (Mw) of 8.0 centered off the coast of central Peru, generated a tsunami with locally focused runup heights of up to 10 m. A reconnaissance team was deployed two weeks after the event and investigated the tsunami effects at 51 sites. Three tsunami fatalities were reported south of the Paracas Peninsula in a sparsely populated desert area where the largest tsunami runup heights and massive inundation distances up to 2 km were measured. Numerical modeling of the earthquake source and tsunami suggest that a region of high slip near the coastline was primarily responsible for the extreme runup heights. The town of Pisco was spared by the Paracas Peninsula, which blocked tsunami waves from propagating northward from the high slip region. As with all near field tsunamis, the waves struck within minutes of the massive ground shaking. Spontaneous evacuations coordinated by the Peruvian Coast Guard minimized the fatalities and illustrate the importance of community-based education and awareness programs. The residents of the fishing village Lagunilla were unaware of the tsunami hazard after an earthquake and did not evacuate, which resulted in 3 fatalities. Despite the relatively benign tsunami effects at Pisco from this event, the tsunami hazard for this city (and its liquefied natural gas terminal) cannot be underestimated. Between 1687 and 1868, the city of Pisco was destroyed 4 times by tsunami waves. Since then, two events (1974 and 2007) have resulted in partial inundation and moderate damage. The fact that potentially devastating tsunami runup heights were observed immediately south of the peninsula only serves to underscore this point.

  5. What caused a large number of fatalities in the Tohoku earthquake?

    Science.gov (United States)

    Ando, M.; Ishida, M.; Nishikawa, Y.; Mizuki, C.; Hayashi, Y.

    2012-04-01

    The Mw9.0 earthquake caused 20,000 deaths and missing persons in northeastern Japan. 115 years prior to this event, there were three historical tsunamis that struck the region, one of which is a "tsunami earthquake" resulted with a death toll of 22,000. Since then, numerous breakwaters were constructed along the entire northeastern coasts and tsunami evacuation drills were carried out and hazard maps were distributed to local residents on numerous communities. However, despite the constructions and preparedness efforts, the March 11 Tohoku earthquake caused numerous fatalities. The strong shaking lasted three minutes or longer, thus all residents recognized that this is the strongest and longest earthquake that they had been ever experienced in their lives. The tsunami inundated an enormous area at about 560km2 over 35 cities along the coast of northeast Japan. To find out the reasons behind the high number of fatalities due to the March 11 tsunami, we interviewed 150 tsunami survivors at public evacuation shelters in 7 cities mainly in Iwate prefecture in mid-April and early June 2011. Interviews were done for about 30min or longer focused on their evacuation behaviors and those that they had observed. On the basis of the interviews, we found that residents' decisions not to evacuate immediately were partly due to or influenced by earthquake science results. Below are some of the factors that affected residents' decisions. 1. Earthquake hazard assessments turned out to be incorrect. Expected earthquake magnitudes and resultant hazards in northeastern Japan assessed and publicized by the government were significantly smaller than the actual Tohoku earthquake. 2. Many residents did not receive accurate tsunami warnings. The first tsunami warning were too small compared with the actual tsunami heights. 3. The previous frequent warnings with overestimated tsunami height influenced the behavior of the residents. 4. Many local residents above 55 years old experienced

  6. Real Time Earthquake Information System in Japan

    Science.gov (United States)

    Doi, K.; Kato, T.

    2003-12-01

    An early earthquake notification system in Japan had been developed by the Japan Meteorological Agency (JMA) as a governmental organization responsible for issuing earthquake information and tsunami forecasts. The system was primarily developed for prompt provision of a tsunami forecast to the public with locating an earthquake and estimating its magnitude as quickly as possible. Years after, a system for a prompt provision of seismic intensity information as indices of degrees of disasters caused by strong ground motion was also developed so that concerned governmental organizations can decide whether it was necessary for them to launch emergency response or not. At present, JMA issues the following kinds of information successively when a large earthquake occurs. 1) Prompt report of occurrence of a large earthquake and major seismic intensities caused by the earthquake in about two minutes after the earthquake occurrence. 2) Tsunami forecast in around three minutes. 3) Information on expected arrival times and maximum heights of tsunami waves in around five minutes. 4) Information on a hypocenter and a magnitude of the earthquake, the seismic intensity at each observation station, the times of high tides in addition to the expected tsunami arrival times in 5-7 minutes. To issue information above, JMA has established; - An advanced nationwide seismic network with about 180 stations for seismic wave observation and about 3,400 stations for instrumental seismic intensity observation including about 2,800 seismic intensity stations maintained by local governments, - Data telemetry networks via landlines and partly via a satellite communication link, - Real-time data processing techniques, for example, the automatic calculation of earthquake location and magnitude, the database driven method for quantitative tsunami estimation, and - Dissemination networks, via computer-to-computer communications and facsimile through dedicated telephone lines. JMA operationally

  7. Influence of Flow Velocity on Tsunami Loss Estimation

    Directory of Open Access Journals (Sweden)

    Jie Song

    2017-11-01

    Full Text Available Inundation depth is commonly used as an intensity measure in tsunami fragility analysis. However, inundation depth cannot be taken as the sole representation of tsunami impact on structures, especially when structural damage is caused by hydrodynamic and debris impact forces that are mainly determined by flow velocity. To reflect the influence of flow velocity in addition to inundation depth in tsunami risk assessment, a tsunami loss estimation method that adopts both inundation depth and flow velocity (i.e., bivariate intensity measures in evaluating tsunami damage is developed. To consider a wide range of possible tsunami inundation scenarios, Monte Carlo-based tsunami simulations are performed using stochastic earthquake slip distributions derived from a spectral synthesis method and probabilistic scaling relationships of earthquake source parameters. By focusing on Sendai (plain coast and Onagawa (ria coast in the Miyagi Prefecture of Japan in a case study, the stochastic tsunami loss is evaluated by total economic loss and its spatial distribution at different scales. The results indicate that tsunami loss prediction is highly sensitive to modelling resolution and inclusion of flow velocity for buildings located less than 1 km from the sea for Sendai and Onagawa of Miyagi Prefecture.

  8. Variability of tsunami inundation footprints considering stochastic scenarios based on a single rupture model: Application to the 2011 Tohoku earthquake

    KAUST Repository

    Goda, Katsuichiro

    2015-06-30

    The sensitivity and variability of spatial tsunami inundation footprints in coastal cities and towns due to a megathrust subduction earthquake in the Tohoku region of Japan are investigated by considering different fault geometry and slip distributions. Stochastic tsunami scenarios are generated based on the spectral analysis and synthesis method with regards to an inverted source model. To assess spatial inundation processes accurately, tsunami modeling is conducted using bathymetry and elevation data with 50 m grid resolutions. Using the developed methodology for assessing variability of tsunami hazard estimates, stochastic inundation depth maps can be generated for local coastal communities. These maps are important for improving disaster preparedness by understanding the consequences of different situations/conditions, and by communicating uncertainty associated with hazard predictions. The analysis indicates that the sensitivity of inundation areas to the geometrical parameters (i.e., top-edge depth, strike, and dip) depends on the tsunami source characteristics and the site location, and is therefore complex and highly nonlinear. The variability assessment of inundation footprints indicates significant influence of slip distributions. In particular, topographical features of the region, such as ria coast and near-shore plain, have major influence on the tsunami inundation footprints.

  9. Defining Tsunami Magnitude as Measure of Potential Impact

    Science.gov (United States)

    Titov, V. V.; Tang, L.

    2016-12-01

    The goal of tsunami forecast, as a system for predicting potential impact of a tsunami at coastlines, requires quick estimate of a tsunami magnitude. This goal has been recognized since the beginning of tsunami research. The work of Kajiura, Soloviev, Abe, Murty, and many others discussed several scales for tsunami magnitude based on estimates of tsunami energy. However, difficulties of estimating tsunami energy based on available tsunami measurements at coastal sea-level stations has carried significant uncertainties and has been virtually impossible in real time, before tsunami impacts coastlines. The slow process of tsunami magnitude estimates, including collection of vast amount of available coastal sea-level data from affected coastlines, made it impractical to use any tsunami magnitude scales in tsunami warning operations. Uncertainties of estimates made tsunami magnitudes difficult to use as universal scale for tsunami analysis. Historically, the earthquake magnitude has been used as a proxy of tsunami impact estimates, since real-time seismic data is available of real-time processing and ample amount of seismic data is available for an elaborate post event analysis. This measure of tsunami impact carries significant uncertainties in quantitative tsunami impact estimates, since the relation between the earthquake and generated tsunami energy varies from case to case. In this work, we argue that current tsunami measurement capabilities and real-time modeling tools allow for establishing robust tsunami magnitude that will be useful for tsunami warning as a quick estimate for tsunami impact and for post-event analysis as a universal scale for tsunamis inter-comparison. We present a method for estimating the tsunami magnitude based on tsunami energy and present application of the magnitude analysis for several historical events for inter-comparison with existing methods.

  10. A Tsunami Fragility Assessment for Nuclear Power Plants in Korea

    International Nuclear Information System (INIS)

    Kim, Min Kyu; Choi, In Kil; Kang, Keum Seok

    2009-01-01

    Although Tsunami events were defined as an external event in 'PRA Procedure Guide (NUREG/CR- 2300)'after 1982, a Tsunami event was not considered in a design and construction of NPP before the Sumatra earthquake in 2004. But the Madras Atomic Power Station, a commercial nuclear power plant owned and operated by the Nuclear Power Corporation of India Limited (NPCIL), and located near Chennai, India, was affected by the tsunami generated by the 2004 Sumatra earthquake (USNRC 2008). The condenser cooling pumps of Unit 2 of the installation were affected due to flooding of the pump house and subsequent submergence of the seawater pumps by tsunami waves. The turbine was tripped and the reactor shut down. The unit was brought to a cold-shutdown state, and the shutdown-cooling systems were reported as operating safely. After this event, Tsunami hazards were considered as one of the major natural disasters which can affect the safety of Nuclear Power Plants. The IAEA performed an Extrabudgetary project for Tsunami Hazard Assessment and finally an International Seismic Safety Center (ISSC) established in IAEA for protection from natural disasters like earthquake, tsunami etc. For this reason, a tsunami hazard assessment method determined in this study. At first, a procedure for tsunami hazard assessment method was established, and second target equipment and structures for investigation of Tsunami Hazard assessment were selected. Finally, a sample fragility calculation was performed for one of equipment in Nuclear Power Plant

  11. High tsunami frequency as a result of combined strike-slip faulting and coastal landslides

    Science.gov (United States)

    Hornbach, Matthew J.; Braudy, Nicole; Briggs, Richard W.; Cormier, Marie-Helene; Davis, Marcy B.; Diebold, John B.; Dieudonne, Nicole; Douilly, Roby; Frohlich, Cliff; Gulick, Sean P.S.; Johnson, Harold E.; Mann, Paul; McHugh, Cecilia; Ryan-Mishkin, Katherine; Prentice, Carol S.; Seeber, Leonardo; Sorlien, Christopher C.; Steckler, Michael S.; Symithe, Steeve Julien; Taylor, Frederick W.; Templeton, John

    2010-01-01

    Earthquakes on strike-slip faults can produce devastating natural hazards. However, because they consist predominantly of lateral motion, these faults are rarely associated with significant uplift or tsunami generation. And although submarine slides can generate tsunami, only a few per cent of all tsunami are believed to be triggered in this way. The 12 January Mw 7.0 Haiti earthquake exhibited primarily strike-slip motion but nevertheless generated a tsunami. Here we present data from a comprehensive field survey that covered the onshore and offshore area around the epicentre to document that modest uplift together with slope failure caused tsunamigenesis. Submarine landslides caused the most severe tsunami locally. Our analysis suggests that slide-generated tsunami occur an order-of-magnitude more frequently along the Gonave microplate than global estimates predict. Uplift was generated because of the earthquake's location, where the Caribbean and Gonave microplates collide obliquely. The earthquake also caused liquefaction at several river deltas that prograde rapidly and are prone to failure. We conclude that coastal strike-slip fault systems such as the Enriquillo-Plantain Garden fault produce relief conducive to rapid sedimentation, erosion and slope failure, so that even modest predominantly strike-slip earthquakes can cause potentially catastrophic slide-generated tsunami - a risk that is underestimated at present.

  12. Possible multihazard events (tsunamis, earthquakes, landslides) expected on the North Bulgarian Black sea coast

    Science.gov (United States)

    Ranguelov, B.; Gospodinopv, D.

    2009-04-01

    Earthquakes The area is famous with its seismic regime. The region usually shows non regular behavior of the strong events occurrence. There are episodes of activation and between them long periods of seismic quiescence. The most important one is at the I-st century BC when according to the chronicler Strabo, the ancient Greek colony "Bisone sank in the waters of the sea". The seismic source is known as Shabla-Kaliakra zone with the best documented seismic event of 31st March 1901. This event had a magnitude of 7.2 (estimated by the macroseismic transformation formula) with a source depth of about 10-20 km. The epicenter was located in the aquatory of the sea. The observed macroseismic intensity on the land reached the maximum value of X degree MSK. This event produced a number of secondary effects - landslides, rockfalls, subsidence, extensive destruction of the houses located around and tsunami (up to 3 meters height observed at Balchik port. This event is selected as referent one. Tsunamis Such earthquakes (magnitude greater then 7.0) almost always trigger tsunamis. They could be generated by the earthquake rupture process, or more frequently by the secondary triggered phenomena - landslides (submarine or surface) and/or other geodynamic phenomena - rock falls, degradation of gas hydrates, etc. the most famous water level change is described by Strabo - related to the great catastrophe. The area shows also some other expressions about tsunamis - the last one - a non seismic tsunami at 7th May, 2007 with maximum observed amplitudes of about 3 meters water level changes. Landslides The area on the north Bulgarian Black Sea coast is covered by many active landslides. They have different size, depth and activation time. Most of them are located near the coast line thus presenting huge danger about the beaches, tourist infrastructure, population and historical heritage. The most famous landslide (subsidence) is related with the I-st century BC seismic event, when a

  13. 2004 Sumatra Tsunami

    Directory of Open Access Journals (Sweden)

    Vongvisessomjai, S.

    2005-09-01

    Full Text Available A catastrophic tsunami on December 26, 2004 caused devastation in the coastal region of six southern provinces of Thailand on the Andaman Sea coast. This paper summaries the characteristics of tsunami with the aim of informing and warning the public and reducing future casualties and damage.The first part is a review of the records of past catastrophic tsunamis, namely those in Chile in 1960, Alaska in 1964, and Flores, Java, Indonesia, in 1992, and the lessons drawn from these tsunamis. An analysis and the impact of the 2004 Sumatra tsunami is then presented and remedial measures recommended.Results of this study are as follows:Firstly, the 2004 Sumatra tsunami ranked fourth in terms of earthquake magnitude (9.0 M after those in 1960 in Chile (9.5 M, 1899 in Alaska (9.2 M and 1964 in Alaska (9.1 M and ranked first in terms of damage and casualties. It was most destructive when breaking in shallow water nearshore.Secondly, the best alleviation measures are 1 to set up a reliable system for providing warning at the time of an earthquake in order to save lives and reduce damage and 2 to establish a hazard map and implement land-use zoning in the devastated areas, according to the following principles:- Large hotels located at an elevation of not less than 10 m above mean sea level (MSL- Medium hotels located at an elevation of not less than 6 m above MSL- Small hotel located at elevation below 6 m MSL, but with the first floor elevated on poles to allow passage of a tsunami wave- Set-back distances from shoreline established for various developments- Provision of shelters and evacuation directionsFinally, public education is an essential part of preparedness.

  14. Tsunami Hazard Analysis for the Eastern Mediterranean and its Connected Seas

    Science.gov (United States)

    Necmioglu, Ocal; Meral Ozel, Nurcan

    2015-04-01

    Accurate earthquake source parameters are essential for any tsunami hazard assessment and mitigation, including early warning systems. Complex tectonic setting makes the a priori accurate assumptions of earthquake source parameters difficult and characterization of the faulting type is a challenge. Information on tsunamigenic sources is of crucial importance in the Eastern Mediterranean and its Connected Seas, especially considering the short arrival times and lack of offshore sea-level measurements. In addition, the scientific community have had to abandon the paradigm of a ''maximum earthquake'' predictable from simple tectonic parameters (Ruff and Kanamori, 1980) in the wake of the 2004 Sumatra event (Okal, 2010) and one of the lessons learnt from the 2011 Tohoku event was that tsunami hazard maps may need to be prepared for infrequent gigantic earthquakes as well as more frequent smaller-sized earthquakes (Satake, 2011). We have initiated an extensive modeling study to perform a deterministic Tsunami Hazard Analysis for the Eastern Mediterranean and its Connected Seas. Characteristic earthquake source parameters (strike, dip, rake, depth, Mwmax) at each 0.5° x 0.5° size bin for 0-40 km depth (total of 310 bins) and for 40-100 km depth (total of 92 bins) in the Eastern Mediterranean, Aegean and Black Sea region (30°N-48°N and 22°E-44°E) have been assigned from the harmonization of the available databases and previous studies. These parameters have been used as input parameters for the deterministic tsunami hazard modeling. Nested Tsunami simulations of 6h duration with a coarse (2 arc-min) grid resolution have been simulated at EC-JRC premises for Black Sea and Eastern and Central Mediterranean (30°N-41.5°N and 8°E-37°E) for each source defined using shallow water finite-difference SWAN code (Mader, 2004) for the magnitude range of 6.5 - Mwmax defined for that bin with a Mw increment of 0.1. Results show that not only the earthquakes resembling the

  15. Toward tsunami early warning system in Indonesia by using rapid rupture durations estimation

    International Nuclear Information System (INIS)

    Madlazim

    2012-01-01

    Indonesia has Indonesian Tsunami Early Warning System (Ina-TEWS) since 2008. The Ina-TEWS has used automatic processing on hypocenter; Mwp, Mw (mB) and Mj. If earthquake occurred in Ocean, depth 7, then Ina-TEWS announce early warning that the earthquake can generate tsunami. However, the announcement of the Ina-TEWS is still not accuracy. Purposes of this research are to estimate earthquake rupture duration of large Indonesia earthquakes that occurred in Indian Ocean, Java, Timor sea, Banda sea, Arafura sea and Pasific ocean. We analyzed at least 330 vertical seismogram recorded by IRIS-DMC network using a direct procedure for rapid assessment of earthquake tsunami potential using simple measures on P-wave vertical seismograms on the velocity records, and the likelihood that the high-frequency, apparent rupture duration, T dur . T dur can be related to the critical parameters rupture length (L), depth (z), and shear modulus (μ) while T dur may be related to wide (W), slip (D), z or μ. Our analysis shows that the rupture duration has a stronger influence to generate tsunami than Mw and depth. The rupture duration gives more information on tsunami impact, Mo/μ, depth and size than Mw and other currently used discriminants. We show more information which known from the rupture durations. The longer rupture duration, the shallower source of the earthquake. For rupture duration greater than 50 s, the depth less than 50 km, Mw greater than 7, the longer rupture length, because T dur is proportional L and greater Mo/μ. Because Mo/μ is proportional L. So, with rupture duration information can be known information of the four parameters. We also suggest that tsunami potential is not directly related to the faulting type of source and for events that have rupture duration greater than 50 s, the earthquakes generated tsunami. With available real-time seismogram data, rapid calculation, rupture duration discriminant can be completed within 4–5 min after an earthquake

  16. The 15 August 2007 Peru tsunami runup observations and modeling

    Science.gov (United States)

    Fritz, Hermann M.; Kalligeris, Nikos; Borrero, Jose C.; Broncano, Pablo; Ortega, Erick

    2008-05-01

    On 15 August 2007 an earthquake with moment magnitude (Mw) of 8.0 centered off the coast of central Peru, generated a tsunami with locally focused runup heights of up to10 m. A reconnaissance team was deployed two weeks after the event and investigated the tsunami effects at 51 sites. Three tsunami fatalities were reported south of the Paracas Peninsula in a sparsely populated desert area where the largest tsunami runup heights were measured. Numerical modeling of the earthquake source and tsunami suggest that a region of high slip near the coastline was primarily responsible for the extreme runup heights. The town of Pisco was spared by the Paracas Peninsula, which blocked tsunami waves from propagating northward from the high slip region. The coast of Peru has experienced numerous deadly and destructive tsunamis throughout history, which highlights the importance of ongoing tsunami awareness and education efforts to ensure successful self-evacuation.

  17. Design and challenges for a tsunami early warning system in the Marmara Sea

    Science.gov (United States)

    Necmioğlu, Öcal

    2016-01-01

    Since 1900, around 90,000 people have lost their lives in 76 earthquakes in Turkey, with a total affected population of around 7 million and direct losses of around 25 billion USD. Based on a time-dependent model that includes coseismic and post-seismic effects of the 1999 Kocaeli earthquake with moment magnitude Mw = 7.4, Parsons (J Geophys Res. 109, 2004) concluded that the probability of an earthquake with Mw > 7 in the Sea of Marmara near Istanbul is 35 to 70 % in the next 30 years. According to a 2011 study, an earthquake with Mw = 7.25 on the Main Marmara Fault is expected to heavily damage or destroy 2 to 4 % of around 1,000,000 buildings in Istanbul with a population around 13 million, with 9 to 15 % of the buildings receiving medium damage and 20 to 34 % of the buildings damaged lightly (Erdik, Science 341:72, 2013). In the absence of adequate post-earthquake assembly areas especially in the heavily urbanized Istanbul, it is evident that after a major earthquake, especially in the coastal parts of the city, citizens would be storming to landfill assembly and recreational areas. Besides earthquakes, around 30 tsunamis have been reported by Altınok et al. (Natural Hazards Earth System Science 11:273-293, 2011) in the Marmara Sea. Among those, catastrophic earthquakes such as 1509, 1766, and 1894 resulted in considerable tsunamis and some damage. The latest tsunami observed in Marmara was due to a triggered submarine landslide of the 1999 Mw = 7.4 Kocaeli earthquake which led to reported run-up heights of 1-3 m in most places (Tinti et al., Marine Geology 225:311-330, 2006). In this study, I propose a design for a tsunami warning system specific for the Marmara region that is strongly coupled with the earthquake early warning system (due to the short arrival times of tsunami) and stakeholders of the tsunami mitigation activities, such as local and regional components of disaster and emergency management and civil protection units, to ensure that the citizens

  18. CARIBE WAVE/LANTEX Caribbean and Western Atlantic Tsunami Exercises

    Science.gov (United States)

    von Hillebrandt-Andrade, C.; Whitmore, P.; Aliaga, B.; Huerfano Moreno, V.

    2013-12-01

    Over 75 tsunamis have been documented in the Caribbean and Adjacent Regions over the past 500 years. While most have been generated by local earthquakes, distant generated tsunamis can also affect the region. For example, waves from the 1755 Lisbon earthquake and tsunami were observed in Cuba, Dominican Republic, British Virgin Islands, as well as Antigua, Martinique, Guadalupe and Barbados in the Lesser Antilles. Since 1500, at least 4484 people are reported to have perished in these killer waves. Although the tsunami generated by the 2010 Haiti earthquake claimed only a few lives, in the 1530 El Pilar, Venezuela; 1602 Port Royale, Jamaica; 1918 Puerto Rico; and 1946 Samaná, Dominican Republic tsunamis the death tolls ranged to over a thousand. Since then, there has been an explosive increase in residents, visitors, infrastructure, and economic activity along the coastlines, increasing the potential for human and economic loss. It has been estimated that on any day, upwards of more than 500,000 people could be in harm's way just along the beaches, with hundreds of thousands more working and living in the tsunamis hazard zones. Given the relative infrequency of tsunamis, exercises are a valuable tool to test communications, evaluate preparedness and raise awareness. Exercises in the Caribbean are conducted under the framework of the UNESCO IOC Intergovernmental Coordination Group for the Tsunami and other Coastal Hazards Warning System for the Caribbean and Adjacent Regions (CARIBE EWS) and the US National Tsunami Hazard Mitigation Program. On March 23, 2011, 34 countries and territories participated in the first CARIBE WAVE/LANTEX regional tsunami exercise, while in the second exercise on March 20, 2013 a total of 45 countries and territories participated. 481 organizations (almost 200 more than in 2011) also registered to receive the bulletins issued by the Pacific Tsunami Warning Center (PTWC), West Coast and Alaska Tsunami Warning Center and/or the Puerto Rico

  19. Near-field tsunami early warning and emergency planning in the Mediterranean Sea

    Directory of Open Access Journals (Sweden)

    Gerassimos A. Papadopoulos

    2013-04-01

    Full Text Available The new European project Near-field Tsunami Early Warning and Emergency Planning in the Mediterranean Sea (NEARTOWARN faces the need to develop operational tsunami early warning systems in near-field (local conditions where the travel time of the first tsunami wave is very short, that is less than 30 min, which is a typical case in the North East Atlantic and the Mediterranean Sea region but also elsewhere around the globe. The operational condition that should be fulfilled is that the time of tsunami detection, plus the time of warning transmitting, plus the time of evacuation should not exceed the travel time of the first tsunami wave from its source to the closest evacuation zone. To this goal the time to detect of the causative earthquake should be compressed at the very minimum. In this context the core of the proposed system is a network of seismic early warning devices, which activate and send alert in a few seconds after the generation of a near-field earthquake, when a seismic ground motion exceeding a prescribed threshold is detected. Then civil protection mobilizes to manage the earthquake crisis but also to detect and manage a possible tsunami through a geographical risk management system. For the tsunami detection the system is supported by tide-gauges of radar type, a database of presimulated tsunami scenarios, and a local tsunami decision matrix. The island of Rhodes in the eastern termination of the Hellenic Arc and Trench has been selected for a pilot and operational development of the local tsunami warning system given that the island is a highly popular tourist destination, historically it was hit by large tsunamigenic earthquakes and was recently the master test-site for the pan-European FP6 tsunami research project Tsunami Risk ANd Strategies For the European Region (TRANSFER.

  20. Development of an expert system for tsunami warning: a unit source approach

    International Nuclear Information System (INIS)

    Roshan, A.D.; Pisharady, Ajai S.; Bishnoi, L.R.; Shah, Meet

    2015-01-01

    Coastal region of India has been experiencing tsunamis since historical times. Many nuclear facilities including nuclear power plants (NPPs), located along the coast are thus exposed to the hazards of tsunami. For the safety of these facilities as well as the safety of the citizens it is necessary to predict the possibility of occurrence of tsunamis for a recorded earthquake event and evaluate the tsunami hazard posed by the earthquake. To address these concerns, this work aims to design an expert system for Tsunami Warning for the Indian Coast with emphasis on evaluation of tsunami heights and arrival times at various nuclear facility sites. The expert system identifies possibility or otherwise of a tsunamigenic event based on earthquake data inputs. Rupture parameters are worked out for the event and unit tsunami source estimations which are available as precomputed database are combined appropriately to estimate the wave heights and time of arrivals at desired locations along the coast. The system also predicts tsunami wave heights at some pre-defined locations such as Nuclear Power Plant (NPP) and other nuclear facility sites. Time of arrivals of first wave along Indian coast is also evaluated

  1. Tsunami hazard in the Caribbean: Regional exposure derived from credible worst case scenarios

    Science.gov (United States)

    Harbitz, C. B.; Glimsdal, S.; Bazin, S.; Zamora, N.; Løvholt, F.; Bungum, H.; Smebye, H.; Gauer, P.; Kjekstad, O.

    2012-04-01

    The present study documents a high tsunami hazard in the Caribbean region, with several thousands of lives lost in tsunamis and associated earthquakes since the XIXth century. Since then, the coastal population of the Caribbean and the Central West Atlantic region has grown significantly and is still growing. Understanding this hazard is therefore essential for the development of efficient mitigation measures. To this end, we report a regional tsunami exposure assessment based on potential and credible seismic and non-seismic tsunamigenic sources. Regional tsunami databases have been compiled and reviewed, and on this basis five main scenarios have been selected to estimate the exposure. The scenarios comprise two Mw8 earthquake tsunamis (north of Hispaniola and east of Lesser Antilles), two subaerial/submarine volcano flank collapse tsunamis (Montserrat and Saint Lucia), and one tsunami resulting from a landslide on the flanks of the Kick'em Jenny submarine volcano (north of Grenada). Offshore tsunami water surface elevations as well as maximum water level distributions along the shore lines are computed and discussed for each of the scenarios. The number of exposed people has been estimated in each case, together with a summary of the tsunami exposure for the earthquake and the landslide tsunami scenarios. For the earthquake scenarios, the highest tsunami exposure relative to the population is found for Guadeloupe (6.5%) and Antigua (7.5%), while Saint Lucia (4.5%) and Antigua (5%) have been found to have the highest tsunami exposure relative to the population for the landslide scenarios. Such high exposure levels clearly warrant more attention on dedicated mitigation measures in the Caribbean region.

  2. On The Computation Of The Best-fit Okada-type Tsunami Source

    Science.gov (United States)

    Miranda, J. M. A.; Luis, J. M. F.; Baptista, M. A.

    2017-12-01

    The forward simulation of earthquake-induced tsunamis usually assumes that the initial sea surface elevation mimics the co-seismic deformation of the ocean bottom described by a simple "Okada-type" source (rectangular fault with constant slip in a homogeneous elastic half space). This approach is highly effective, in particular in far-field conditions. With this assumption, and a given set of tsunami waveforms recorded by deep sea pressure sensors and (or) coastal tide stations it is possible to deduce the set of parameters of the Okada-type solution that best fits a set of sea level observations. To do this, we build a "space of possible tsunami sources-solution space". Each solution consists of a combination of parameters: earthquake magnitude, length, width, slip, depth and angles - strike, rake, and dip. To constrain the number of possible solutions we use the earthquake parameters defined by seismology and establish a range of possible values for each parameter. We select the "best Okada source" by comparison of the results of direct tsunami modeling using the solution space of tsunami sources. However, direct tsunami modeling is a time-consuming process for the whole solution space. To overcome this problem, we use a precomputed database of Empirical Green Functions to compute the tsunami waveforms resulting from unit water sources and search which one best matches the observations. In this study, we use as a test case the Solomon Islands tsunami of 6 February 2013 caused by a magnitude 8.0 earthquake. The "best Okada" source is the solution that best matches the tsunami recorded at six DART stations in the area. We discuss the differences between the initial seismic solution and the final one obtained from tsunami data This publication received funding of FCT-project UID/GEO/50019/2013-Instituto Dom Luiz.

  3. Tsunami-hazard assessment based on subaquatic slope-failure susceptibility and tsunami-inundation modeling

    Science.gov (United States)

    Anselmetti, Flavio; Hilbe, Michael; Strupler, Michael; Baumgartner, Christoph; Bolz, Markus; Braschler, Urs; Eberli, Josef; Liniger, Markus; Scheiwiller, Peter; Strasser, Michael

    2015-04-01

    Due to their smaller dimensions and confined bathymetry, lakes act as model oceans that may be used as analogues for the much larger oceans and their margins. Numerous studies in the perialpine lakes of Central Europe have shown that their shores were repeatedly struck by several-meters-high tsunami waves, which were caused by subaquatic slides usually triggered by earthquake shaking. A profound knowledge of these hazards, their intensities and recurrence rates is needed in order to perform thorough tsunami-hazard assessment for the usually densely populated lake shores. In this context, we present results of a study combining i) basinwide slope-stability analysis of subaquatic sediment-charged slopes with ii) identification of scenarios for subaquatic slides triggered by seismic shaking, iii) forward modeling of resulting tsunami waves and iv) mapping of intensity of onshore inundation in populated areas. Sedimentological, stratigraphical and geotechnical knowledge of the potentially unstable sediment drape on the slopes is required for slope-stability assessment. Together with critical ground accelerations calculated from already failed slopes and paleoseismic recurrence rates, scenarios for subaquatic sediment slides are established. Following a previously used approach, the slides are modeled as a Bingham plastic on a 2D grid. The effect on the water column and wave propagation are simulated using the shallow-water equations (GeoClaw code), which also provide data for tsunami inundation, including flow depth, flow velocity and momentum as key variables. Combining these parameters leads to so called «intensity maps» for flooding that provide a link to the established hazard mapping framework, which so far does not include these phenomena. The current versions of these maps consider a 'worst case' deterministic earthquake scenario, however, similar maps can be calculated using probabilistic earthquake recurrence rates, which are expressed in variable amounts of

  4. Real-time tsunami inundation forecasting and damage mapping towards enhancing tsunami disaster resiliency

    Science.gov (United States)

    Koshimura, S.; Hino, R.; Ohta, Y.; Kobayashi, H.; Musa, A.; Murashima, Y.

    2014-12-01

    With use of modern computing power and advanced sensor networks, a project is underway to establish a new system of real-time tsunami inundation forecasting, damage estimation and mapping to enhance society's resilience in the aftermath of major tsunami disaster. The system consists of fusion of real-time crustal deformation monitoring/fault model estimation by Ohta et al. (2012), high-performance real-time tsunami propagation/inundation modeling with NEC's vector supercomputer SX-ACE, damage/loss estimation models (Koshimura et al., 2013), and geo-informatics. After a major (near field) earthquake is triggered, the first response of the system is to identify the tsunami source model by applying RAPiD Algorithm (Ohta et al., 2012) to observed RTK-GPS time series at GEONET sites in Japan. As performed in the data obtained during the 2011 Tohoku event, we assume less than 10 minutes as the acquisition time of the source model. Given the tsunami source, the system moves on to running tsunami propagation and inundation model which was optimized on the vector supercomputer SX-ACE to acquire the estimation of time series of tsunami at offshore/coastal tide gauges to determine tsunami travel and arrival time, extent of inundation zone, maximum flow depth distribution. The implemented tsunami numerical model is based on the non-linear shallow-water equations discretized by finite difference method. The merged bathymetry and topography grids are prepared with 10 m resolution to better estimate the tsunami inland penetration. Given the maximum flow depth distribution, the system performs GIS analysis to determine the numbers of exposed population and structures using census data, then estimates the numbers of potential death and damaged structures by applying tsunami fragility curve (Koshimura et al., 2013). Since the tsunami source model is determined, the model is supposed to complete the estimation within 10 minutes. The results are disseminated as mapping products to

  5. Tsunami hazard assessment for the Azores archipelago: a historical review

    Science.gov (United States)

    Cabral, Nuno; Ferreira, Teresa; Queiroz, Maria Gabriela

    2010-05-01

    The Azores islands due to its complex geographical and geodynamic setting are exposed to tsunamigenic events associated to different triggering mechanisms, local or distant. Since the settlement of the Azores, in the fifteenth century, there are several documents that relate coastal areas flooding episodes with unusually high waves which caused death and destruction. This work had as main objective the characterization of the different events that can be associated with tsunamigenic phenomena, registered in the archipelago. With this aim, it was collected diverse documentation like chronics, manuscripts, newspaper articles and magazines, scientific publications, and international databases available online. From all the studied tsunami events it was identified the occurrence of some teletsunamis, among which the most relevant was triggered by the 1st November 1755 Lisbon earthquake, with an epicenter SW of Portugal, which killed 6 people in Terceira island. It is also noted the teletsunami generated by the 1761 earthquake, located in the same region as the latest, and the one generated in 1929 by an earthquake-triggered submarine landslide in the Grand Banks of Newfoundland. From the local events, originated in the Azores, the most significant were the tsunamis triggered by 1757 and 1980 earthquakes, both associated with the Terceira Rift dynamics. In the first case the waves may also be due to earthquake-triggered. With respect to tsunamis triggered by sea cliffs landslides it is important to mention the 1847 Quebrada Nova and the 1980 Rocha Alta events, both located in the Flores Island. The 1847 event is the deadliest tsunami recorded in Azores since 10 people died in Flores and Corvo islands in result of the propagated wave. The developed studies improve knowledge of the tsunami sources that affected the Azores during its history, also revealing the importance of awareness about this natural phenomenon. The obtained results showed that the tsunami hazard in the

  6. Tsunamigenik di Selat Sunda: Kajian terhadap katalog Tsunami Soloviev

    Directory of Open Access Journals (Sweden)

    Yudhicara Yudhicara

    2014-06-01

    Full Text Available http://dx.doi.org/10.17014/ijog.vol3no4.20086Tsunamigenic is a natural phenomena which is potential to generate a tsunami, such as water dis- turbance due to the presence of activities of volcanism, earthquakes, coastal and sub marine landslidse, or other causal factors . Historically, the Sunda Strait has experienced several tsunami events recorded in the tsunami catalog. Those tsunamies were caused by some geological phenomena such as eruptions of Krakatau submarine volcano in 416, 1883, and 1928; earthquakes in 1722, 1852, and 1958; and other causes which were suggested as a mass failure of coastal and submarine landslide in 1851, 1883, and 1889. Tectonic condition of the Sunda Strait is very complicated, because this region is located at the boundary of Indian-Australian and Eurasian Plates, where a unique island arc system occurs with its association such as trench, accretionary zone, volcanic arc and back-arc basin. Sunda trench as a plate boundary is the most potential region to produce big earthquakes. Existence of a seismic gap in the region can cause a stress accumulation and store energy, then it will be released any time as a big earthquake to generate a tsunami. Along eruption history, Krakatau volcanic arc has four stages of reconstruction and three stages of destruction, and every destruction stage produces tsunami which is suggested to be potentially repeated in the future in a period between 2500 to 2700. Seafloor of the Sunda Strait has an unstable geological condition due to geological structure development, which creates grabens and also enable to produce submarine landslides triggered by earthquake. Coastal condition around the Semangko and Lampung Bays consisting of steep topography with high intensity of weathering, is another factor to contribute landslide, particularly in the case of triggering be heavy rainfall between December to Februari. Furthermore, if landslide materials tumble into the water, even very small and

  7. TOWARD INDONESIAN TSUNAMI EARLY WARNING SYSTEM BY USING RAPID RUPTURE DURATIONS CALCULATION

    Directory of Open Access Journals (Sweden)

    M. Adlazim

    2011-01-01

    Full Text Available Indonesia has an Indonesian Tsunami Early Warning System (Ina-TEWS since 2008. The Ina-TEWS has used automatic processing on hypocenter; Mwp, Mw (mB and Mj. If earthquake occurred in Ocean, depth 7, then Ina-TEWS announce early warning that the earthquake can generate tsunami. However, the announcement of the Ina-TEWS is still not accuracy. Purpose of this study is to estimate earthquake rupture duration of large Indonesia earthquakes that occurred in Indian Ocean, Java, Timor Sea, Banda Sea, Arafura Sea and Pacific Ocean using a direct procedure and software developed Lomax and Michelini for rapid assessment of earthquake tsunami potential by deriving two simple measures from vertical component broadband P-wave velocity record. The first is the high-frequency apparent rupture duration, Tdur which may be related to can be related to the critical parameters rupture length (L, depth (z, and shear modulus (μ. The second is a confirmation of the earlier finding by Lomax and Michelini, namely that the rupture duration has a stronger influence to generate tsunami than Mw and Depth. We analyzed at least 510 vertical seismogram recorded by GEOFON-IA and IRIS-DMC networks. Our analysis shows that the seismic potency, LWD, which is more obviously related to capability to generate a tsunami than former. The larger Tdur the larger is the seismic potency LWD because Tdur is proportional to L/vr (with vr – rupture velocity. We also suggest that tsunami potential is not directly related to the faulting type of source and for events that have rupture duration greater than 50 s, the earthquakes generated tsunami. With available real-time seismogram data, rapid calculation, rupture duration discriminant can be completed within 3 to 8 min after the P-onset.

  8. POTENTIAL DEFICIENCIES IN EDUCATION, INSTRUMENTATION, AND WARNINGS FOR LOCALLY GENERATED TSUNAMIS

    Directory of Open Access Journals (Sweden)

    Daniel A. Walker

    2010-01-01

    Full Text Available A review of historical data for Hawaii reveals that significant tsunamis have been reported for only four of twenty-six potentially tsunamigenic earthquakes from 1868 through 2009 with magnitudes of 6.0 or greater. During the same time period, three significant tsunamis have been reported for substantially smaller earthquakes. This historical perspective, the fact that the last significant local tsunami occurred in 1975, and an understandable preoccupation with tsunamis generated around the margins of the Pacific, all combine to suggest apparent deficiencies in: (1 personal awareness of what to do in the event of a possible local tsunami; (2 the distribution of instrumentation capable of providing rapid confirmation that a local tsunami has been generated; and (3 the subsequent issuance of timely warnings for local tsunamis. With these deficiencies, far more lives may be lost in Hawaii due to local tsunamis than will result from tsunamis that have originated along the margins of the Pacific. Similar deficiencies may exist in other areas of the world threatened by local tsunamis.

  9. A new survey method of tsunami inundation area using chemical analysis of soil. Application to the field survey on the 2010 Chilean tsunami at Chile

    International Nuclear Information System (INIS)

    Yoshii, Takumi; Matsuyama, Masafumi; Koshimura, Shunichi; Mas, Erick; Matsuoka, Masashi; Jimenez, Cesar

    2011-01-01

    The severe earthquake of Mw 8.8 occurred on 27 Feb. 2010 at the center of Chile. The tsunami generated by the earthquake attacked the coast of Chile and it propagated to the Pacific Ocean coastline. The field survey on the disaster damages due to the tsunami was conducted near Talcahuano in Chile to prepare for the great tsunamis accompanied by the earthquakes predicted to occur near Japan within several decades. The aims of this field survey were to survey disaster damages especially relevant to electric equipments and to develop the survey method based on a chemical analysis of the inundated soil which supplies objective data with high accuracy compared to the conventional methods. In the survey area, the average of inundation heights was 6 m, however it locally reached up to 25 m. The maximum sea-level height of the series of the tsunamis was recorded in the third or fourth wave (roughly 3 hours after the earthquake occurrence). The first floors of houses were severely destroyed and some ships were carried and left on land by the tsunamis. Furthermore, the large amount of sediment was deposited in towns. Removing the drifted ships and tsunami deposit is important consideration for quick recovery from a disaster due to a tsunami. The soil samples were obtained from both the inundated and the not-inundated position. The stirred solution was made by the soil and ultrapure water, then, the content of water-soluble ions, electric conductivity (EC), and pH were measured. The soil obtained in the tsunami inundated area contains much water-soluble ions (Na + , Mg 2+ , Cl - , Br - , SO 4 2- ) compared to the samples obtained in the not-inundated area. The discriminant analysis of the tsunami inundation was conducted using the amount of ions in the soil. High discriminant accuracy (over 90%) was obtained with Na + , Mg 2+ , Cl - , Br - , SO 4 2- and EC. Br - , Cl - , Na + are believed to be suitable for the discriminant analysis about tsunamis considering the contaminant

  10. The potential role of real-time geodetic observations in tsunami early warning

    Science.gov (United States)

    Tinti, Stefano; Armigliato, Alberto

    2016-04-01

    Tsunami warning systems (TWS) have the final goal to launch a reliable alert of an incoming dangerous tsunami to coastal population early enough to allow people to flee from the shore and coastal areas according to some evacuation plans. In the last decade, especially after the catastrophic 2004 Boxing Day tsunami in the Indian Ocean, much attention has been given to filling gaps in the existing TWSs (only covering the Pacific Ocean at that time) and to establishing new TWSs in ocean regions that were uncovered. Typically, TWSs operating today work only on earthquake-induced tsunamis. TWSs estimate quickly earthquake location and size by real-time processing seismic signals; on the basis of some pre-defined "static" procedures (either based on decision matrices or on pre-archived tsunami simulations), assess the tsunami alert level on a large regional scale and issue specific bulletins to a pre-selected recipients audience. Not unfrequently these procedures result in generic alert messages with little value. What usually operative TWSs do not do, is to compute earthquake focal mechanism, to calculate the co-seismic sea-floor displacement, to assess the initial tsunami conditions, to input these data into tsunami simulation models and to compute tsunami propagation up to the threatened coastal districts. This series of steps is considered nowadays too time consuming to provide the required timely alert. An equivalent series of steps could start from the same premises (earthquake focal parameters) and reach the same result (tsunami height at target coastal areas) by replacing the intermediate steps of real-time tsunami simulations with proper selection from a large archive of pre-computed tsunami scenarios. The advantage of real-time simulations and of archived scenarios selection is that estimates are tailored to the specific occurring tsunami and alert can be more detailed (less generic) and appropriate for local needs. Both these procedures are still at an

  11. The tsunami's impact on mortality in a town severely damaged by the 2011 Great East Japan Earthquake.

    Science.gov (United States)

    Nagata, Satoko; Teramoto, Chie; Okamoto, Reiko; Koide, Keiko; Nishida, Masumi; Suzuki, Ruriko; Nomura, Michie; Tada, Toshiko; Kishi, Emiko; Sakai, Yoko; Jojima, Noriko; Kusano, Emiko; Iwamoto, Saori; Saito, Miki; Murashima, Sachiyo

    2014-07-01

    This study identifies the relationship between tsunami damage and mortality through a demographic pyramid of a town severely damaged by the tsunami following the Great East Japan Earthquake of 11 March 2011. It uses cross-sectional data collection. Volunteers visited all households, including shelters, and asked residents about the whereabouts of family members and neighbours. The information was collated with lists of evacuees and the dead to confirm the whereabouts of all residents about 50 days after the disaster. Demographic pyramids for the whole population based on pre- and post-disaster data were drawn. In all, 1,412 (8.8 per cent) were dead or missing, 60.2 per cent of whom were aged 65 and over and 37.5 per cent aged 75 and over, suggesting that the very old should be located beyond the reach of tsunamis. The mortality rate of children was lower than that in other studies, which may indicate the efficacy of disaster evacuation drills. © 2014 The Author(s). Disasters © Overseas Development Institute, 2014.

  12. Development of Physics and Control of Multiple Forcing Mechanisms for the Alaska Tsunami Forecast Model

    Science.gov (United States)

    Bahng, B.; Whitmore, P.; Macpherson, K. A.; Knight, W. R.

    2016-12-01

    The Alaska Tsunami Forecast Model (ATFM) is a numerical model used to forecast propagation and inundation of tsunamis generated by earthquakes or other mechanisms in either the Pacific Ocean, Atlantic Ocean or Gulf of Mexico. At the U.S. National Tsunami Warning Center (NTWC), the use of the model has been mainly for tsunami pre-computation due to earthquakes. That is, results for hundreds of hypothetical events are computed before alerts, and are accessed and calibrated with observations during tsunamis to immediately produce forecasts. The model has also been used for tsunami hindcasting due to submarine landslides and due to atmospheric pressure jumps, but in a very case-specific and somewhat limited manner. ATFM uses the non-linear, depth-averaged, shallow-water equations of motion with multiply nested grids in two-way communications between domains of each parent-child pair as waves approach coastal waters. The shallow-water wave physics is readily applicable to all of the above tsunamis as well as to tides. Recently, the model has been expanded to include multiple forcing mechanisms in a systematic fashion, and to enhance the model physics for non-earthquake events.ATFM is now able to handle multiple source mechanisms, either individually or jointly, which include earthquake, submarine landslide, meteo-tsunami and tidal forcing. As for earthquakes, the source can be a single unit source or multiple, interacting source blocks. Horizontal slip contribution can be added to the sea-floor displacement. The model now includes submarine landslide physics, modeling the source either as a rigid slump, or as a viscous fluid. Additional shallow-water physics have been implemented for the viscous submarine landslides. With rigid slumping, any trajectory can be followed. As for meteo-tsunami, the forcing mechanism is capable of following any trajectory shape. Wind stress physics has also been implemented for the meteo-tsunami case, if required. As an example of multiple

  13. A rapid estimation of near field tsunami run-up

    Science.gov (United States)

    Riqueime, Sebastian; Fuentes, Mauricio; Hayes, Gavin; Campos, Jamie

    2015-01-01

    Many efforts have been made to quickly estimate the maximum run-up height of tsunamis associated with large earthquakes. This is a difficult task, because of the time it takes to construct a tsunami model using real time data from the source. It is possible to construct a database of potential seismic sources and their corresponding tsunami a priori.However, such models are generally based on uniform slip distributions and thus oversimplify the knowledge of the earthquake source. Here, we show how to predict tsunami run-up from any seismic source model using an analytic solution, that was specifically designed for subduction zones with a well defined geometry, i.e., Chile, Japan, Nicaragua, Alaska. The main idea of this work is to provide a tool for emergency response, trading off accuracy for speed. The solutions we present for large earthquakes appear promising. Here, run-up models are computed for: The 1992 Mw 7.7 Nicaragua Earthquake, the 2001 Mw 8.4 Perú Earthquake, the 2003Mw 8.3 Hokkaido Earthquake, the 2007 Mw 8.1 Perú Earthquake, the 2010 Mw 8.8 Maule Earthquake, the 2011 Mw 9.0 Tohoku Earthquake and the recent 2014 Mw 8.2 Iquique Earthquake. The maximum run-up estimations are consistent with measurements made inland after each event, with a peak of 9 m for Nicaragua, 8 m for Perú (2001), 32 m for Maule, 41 m for Tohoku, and 4.1 m for Iquique. Considering recent advances made in the analysis of real time GPS data and the ability to rapidly resolve the finiteness of a large earthquake close to existing GPS networks, it will be possible in the near future to perform these calculations within the first minutes after the occurrence of similar events. Thus, such calculations will provide faster run-up information than is available from existing uniform-slip seismic source databases or past events of pre-modeled seismic sources.

  14. Towards Deep Learning from Twitter for Improved Tsunami Alerts and Advisories

    Science.gov (United States)

    Lumb, L. I.; Freemantle, J. R.

    2017-12-01

    Data from social-networking services increasingly complements that from traditional sources in scenarios that seek to 'cultivate' situational awareness. As false-positive alerts and retracted advisories appear to suggest, establishing a causal connection between earthquakes and tsunamis remains an extant challenge that could prove life-critical. Because posts regarding such natural disasters typically 'trend' in real time via social media, we extract tweets in an effort to elucidate this cause-effect relationship from a very different perspective. To extract content of potential geophysical value from a multiplicity of 140-character tweets streamed in real time, we apply Natural Language Processing (NLP) to the unstructured data and metadata available via Twitter. In Deep Learning from Twitter, words such as "earthquake" are represented as vectors embedded in a corpora of tweets, whose proximity to words such as "tsunami" can be subsequently quantified. Furthermore, when use is made of pre-trained word vectors available for various reference corpora, geophysically credible tweets are rendered distinguishable by quantifying similarities through use of a word-vector dot product. Finally, word-vector analogies are shown to be promising in terms of deconstructing the earthquake-tsunami relationship in terms of the cumulative effect of multiple, contributing factors (see figure). Because diction is anticipated to differ in tweets that follow a tsunami-producing earthquake, our emphasis here is on the re-analysis of actual event data extracted from Twitter that quantifies word sense relative to earthquake-only events. If proven viable, our approach could complement those measures already in place to deliver real-time alerts and advisories following tsunami-causing earthquakes. With climate change accelerating the frequency of glacial calving, and in so doing providing an alternate, potential source for tsunamis, our approach is anticipated to be of value in broader

  15. Emergency preparedness in the case of Makran tsunami: a case study on tsunami risk visualization for the western parts of Gujarat, India

    Directory of Open Access Journals (Sweden)

    V. M. Patel

    2016-03-01

    Full Text Available The west coast of India is affected by tsunamigenic earthquake along the Makran subduction zone. On 28 November 1945 at 21:56 coordinated universal time (UTC, a massive Makran earthquake (M8.0 generated a destructive tsunami that propagated across the Northern Arabian Sea and the Indian Ocean. This tsunamigenic earthquake was responsible for the loss of life and great destruction along the coasts of India, Pakistan, Iran and Oman. Modelling of tsunami stages has been made for the coasts of Pakistan, Iran, India and Oman using NAMI-DANCE computer code. The fault parameters of the earthquakes for the generation of tsunami are epicentre (25.15° N, 63.48° E, fault area (200 km length and 100 km width, angle of strike, dip and rake (246°, 7° and 90°, focal depth (15 km, slip magnitude (7 m. The bathymetry data are taken from General Bathymetric Chart of the Oceans (GEBCO and land topography data were collected using Shuttle Radar Topography Mission (SRTM. The present simulation is carried out for a duration of 360 min. It is observed that the maximum calculated tsunami run-ups were about 0.7–1.1 m along the coast of Oman, 0.5 m near Muscat, 0.1 m near Sur, 0.7–1.35 m along the western coast of India, 0.5–2.3 m along the southern coast of Iran and 1.2–5.8 m along the southern coast of Pakistan. After the tsunamigenic earthquake, the tsunami wave reached the Gulf of Kachchh in about 240 min, Okha in about 185 min, Dwarka in about 150 min, Porbandar in about 155 min, Mumbai in about 300 min and Goa in about 210 min. The calculated 2-hr tsunami travel time to the Indian coast is in good agreement with the available reports and published data. If the tsunami strikes during high tide, we should expect more serious hazards which would impact local coastal communities. The results obtained in this study are converted to be compatible with the geographic information system based applications for display and spatial analysis of

  16. A rapid estimation of tsunami run-up based on finite fault models

    Science.gov (United States)

    Campos, J.; Fuentes, M. A.; Hayes, G. P.; Barrientos, S. E.; Riquelme, S.

    2014-12-01

    Many efforts have been made to estimate the maximum run-up height of tsunamis associated with large earthquakes. This is a difficult task, because of the time it takes to construct a tsunami model using real time data from the source. It is possible to construct a database of potential seismic sources and their corresponding tsunami a priori. However, such models are generally based on uniform slip distributions and thus oversimplify our knowledge of the earthquake source. Instead, we can use finite fault models of earthquakes to give a more accurate prediction of the tsunami run-up. Here we show how to accurately predict tsunami run-up from any seismic source model using an analytic solution found by Fuentes et al, 2013 that was especially calculated for zones with a very well defined strike, i.e, Chile, Japan, Alaska, etc. The main idea of this work is to produce a tool for emergency response, trading off accuracy for quickness. Our solutions for three large earthquakes are promising. Here we compute models of the run-up for the 2010 Mw 8.8 Maule Earthquake, the 2011 Mw 9.0 Tohoku Earthquake, and the recent 2014 Mw 8.2 Iquique Earthquake. Our maximum rup-up predictions are consistent with measurements made inland after each event, with a peak of 15 to 20 m for Maule, 40 m for Tohoku, and 2,1 m for the Iquique earthquake. Considering recent advances made in the analysis of real time GPS data and the ability to rapidly resolve the finiteness of a large earthquake close to existing GPS networks, it will be possible in the near future to perform these calculations within the first five minutes after the occurrence of any such event. Such calculations will thus provide more accurate run-up information than is otherwise available from existing uniform-slip seismic source databases.

  17. The tsunami probabilistic risk assessment of nuclear power plant (3). Outline of tsunami fragility analysis

    International Nuclear Information System (INIS)

    Mihara, Yoshinori

    2012-01-01

    Tsunami Probabilistic Risk Assessment (PRA) standard was issued in February 2012 by Standard Committee of Atomic Energy Society of Japan (AESJ). This article detailed tsunami fragility analysis, which calculated building and structure damage probability contributing core damage and consisted of five evaluation steps: (1) selection of evaluated element and damage mode, (2) selection of evaluation procedure, (3) evaluation of actual stiffness, (4) evaluation of actual response and (5) evaluation of fragility (damage probability and others). As an application example of the standard, calculation results of tsunami fragility analysis investigation by tsunami PRA subcommittee of AESJ were shown reflecting latest knowledge of damage state caused by wave force and others acted by tsunami from the 'off the Pacific Coast of Tohoku Earthquake'. (T. Tanaka)

  18. Assessment of tsunami hazard for coastal areas of Shandong Province, China

    Science.gov (United States)

    Feng, Xingru; Yin, Baoshu

    2017-04-01

    Shandong province is located on the east coast of China and has a coastline of about 3100 km. There are only a few tsunami events recorded in the history of Shandong Province, but the tsunami hazard assessment is still necessary as the rapid economic development and increasing population of this area. The objective of this study was to evaluate the potential danger posed by tsunamis for Shandong Province. The numerical simulation method was adopted to assess the tsunami hazard for coastal areas of Shandong Province. The Cornell multi-grid coupled tsunami numerical model (COMCOT) was used and its efficacy was verified by comparison with three historical tsunami events. The simulated maximum tsunami wave height agreed well with the observational data. Based on previous studies and statistical analyses, multiple earthquake scenarios in eight seismic zones were designed, the magnitudes of which were set as the potential maximum values. Then, the tsunamis they induced were simulated using the COMCOT model to investigate their impact on the coastal areas of Shandong Province. The numerical results showed that the maximum tsunami wave height, which was caused by the earthquake scenario located in the sea area of the Mariana Islands, could reach up to 1.39 m off the eastern coast of Weihai city. The tsunamis from the seismic zones of the Bohai Sea, Okinawa Trough, and Manila Trench could also reach heights of >1 m in some areas, meaning that earthquakes in these zones should not be ignored. The inundation hazard was distributed primarily in some northern coastal areas near Yantai and southeastern coastal areas of Shandong Peninsula. When considering both the magnitude and arrival time of tsunamis, it is suggested that greater attention be paid to earthquakes that occur in the Bohai Sea. In conclusion, the tsunami hazard facing the coastal area of Shandong Province is not very serious; however, disasters could occur if such events coincided with spring tides or other

  19. Tsunami disaster risk management capabilities in Greece

    Science.gov (United States)

    Marios Karagiannis, Georgios; Synolakis, Costas

    2015-04-01

    Greece is vulnerable to tsunamis, due to the length of the coastline, its islands and its geographical proximity to the Hellenic Arc, an active subduction zone. Historically, about 10% of all world tsunamis occur in the Mediterranean region. Here we review existing tsunami disaster risk management capabilities in Greece. We analyze capabilities across the disaster management continuum, including prevention, preparedness, response and recovery. Specifically, we focus on issues like legal requirements, stakeholders, hazard mitigation practices, emergency operations plans, public awareness and education, community-based approaches and early-warning systems. Our research is based on a review of existing literature and official documentation, on previous projects, as well as on interviews with civil protection officials in Greece. In terms of tsunami disaster prevention and hazard mitigation, the lack of tsunami inundation maps, except for some areas in Crete, makes it quite difficult to get public support for hazard mitigation practices. Urban and spatial planning tools in Greece allow the planner to take into account hazards and establish buffer zones near hazard areas. However, the application of such ordinances at the local and regional levels is often difficult. Eminent domain is not supported by law and there are no regulatory provisions regarding tax abatement as a disaster prevention tool. Building codes require buildings and other structures to withstand lateral dynamic earthquake loads, but there are no provisions for resistance to impact loading from water born debris Public education about tsunamis has increased during the last half-decade but remains sporadic. In terms of disaster preparedness, Greece does have a National Tsunami Warning Center (NTWC) and is a Member of UNESCO's Tsunami Program for North-eastern Atlantic, the Mediterranean and connected seas (NEAM) region. Several exercises have been organized in the framework of the NEAM Tsunami Warning

  20. Correlation Equation of Fault Size, Moment Magnitude, and Height of Tsunami Case Study: Historical Tsunami Database in Sulawesi

    Science.gov (United States)

    Julius, Musa, Admiral; Pribadi, Sugeng; Muzli, Muzli

    2018-03-01

    Sulawesi, one of the biggest island in Indonesia, located on the convergence of two macro plate that is Eurasia and Pacific. NOAA and Novosibirsk Tsunami Laboratory show more than 20 tsunami data recorded in Sulawesi since 1820. Based on this data, determination of correlation between tsunami and earthquake parameter need to be done to proved all event in the past. Complete data of magnitudes, fault sizes and tsunami heights on this study sourced from NOAA and Novosibirsk Tsunami database, completed with Pacific Tsunami Warning Center (PTWC) catalog. This study aims to find correlation between moment magnitude, fault size and tsunami height by simple regression. The step of this research are data collecting, processing, and regression analysis. Result shows moment magnitude, fault size and tsunami heights strongly correlated. This analysis is enough to proved the accuracy of historical tsunami database in Sulawesi on NOAA, Novosibirsk Tsunami Laboratory and PTWC.

  1. Red semántica de terremoto y maremoto en personas expuestas directa y vicariamente Rede semântica de terremoto e tsunami em pessoas expostas diretamente e vicariamente Semantic networks of earthquake and tsunami in people exposed directly and vicariously

    Directory of Open Access Journals (Sweden)

    Emilio Moyano Díaz

    2012-12-01

    Full Text Available Se busca identificar el significado de los conceptos 'terremoto' y 'maremoto' en dos grupos diferentemente expuestos al evento acaecido en Chile el 27/02/2010, en una muestra no probabilística intencional, compuesta por 240 personas provenientes de las ciudades de Constitución (n=104 - expuestas directamente al terremoto y maremoto -, y de Punta Arenas (n=136 expuestas vicariamente. Mediante redes semánticas naturales (R.S. construidas ad-hoc, fue observado que terremoto y tsunami tienen significados semejantes, relacionados al miedo, muerte, destrucción, desesperación, desastre, pérdida, angustia, tristeza, pena, dolor y pánico. Adicionalmente, aquellos que vivieron directamente el fenómeno utilizan más definidoras de tipo emocional al definir terremoto que aquellos que fueron expuestos a él de modo vicario.Procurou-se identificar o significado dos conceitos 'terremoto' e 'tsunami' em dois grupos diferentemente expostos ao evento acontecido no Chile em 27/02/2010, em uma amostra não-probabilística intencional, composta por 240 pessoas provenientes das cidades de Constitución (n=104, expostas diretamente ao terremoto e ao maremoto, e de Punta Arenas (n=136, expostas vicariamente. Pelas redes semânticas naturais (R.S. construídas ad hoc, foi observado que terremoto e tsunami têm significados semelhantes, relacionadas a medo, morte, destruição, desespero, desastre, perda, angústia, tristeza, pena, dor e pânico. Além disso, aqueles que experimentaram diretamente o fenômeno tendem a usar mais palavras de cunho emocional para definir terremoto, do que aqueles que foram expostos a ele vicariamen.The purpose of this research was to describe the meaning of "earthquake" and "tsunami" in two groups with different exposures to the Chilean natural disaster on February 27th, 2010. A non-probabilistic sample of two-hundred-forty subjects from Constitución (n=104 and Punta Arenas (n=136 was selected. The first group was directly exposed

  2. Proposal of a method for evaluating tsunami risk using response-surface methodology

    Science.gov (United States)

    Fukutani, Y.

    2017-12-01

    Information on probabilistic tsunami inundation hazards is needed to define and evaluate tsunami risk. Several methods for calculating these hazards have been proposed (e.g. Løvholt et al. (2012), Thio (2012), Fukutani et al. (2014), Goda et al. (2015)). However, these methods are inefficient, and their calculation cost is high, since they require multiple tsunami numerical simulations, therefore lacking versatility. In this study, we proposed a simpler method for tsunami risk evaluation using response-surface methodology. Kotani et al. (2016) proposed an evaluation method for the probabilistic distribution of tsunami wave-height using a response-surface methodology. We expanded their study and developed a probabilistic distribution of tsunami inundation depth. We set the depth (x1) and the slip (x2) of an earthquake fault as explanatory variables and tsunami inundation depth (y) as an object variable. Subsequently, tsunami risk could be evaluated by conducting a Monte Carlo simulation, assuming that the generation probability of an earthquake follows a Poisson distribution, the probability distribution of tsunami inundation depth follows the distribution derived from a response-surface, and the damage probability of a target follows a log normal distribution. We applied the proposed method to a wood building located on the coast of Tokyo Bay. We implemented a regression analysis based on the results of 25 tsunami numerical calculations and developed a response-surface, which was defined as y=ax1+bx2+c (a:0.2615, b:3.1763, c=-1.1802). We assumed proper probabilistic distribution for earthquake generation, inundation height, and vulnerability. Based on these probabilistic distributions, we conducted Monte Carlo simulations of 1,000,000 years. We clarified that the expected damage probability of the studied wood building is 22.5%, assuming that an earthquake occurs. The proposed method is therefore a useful and simple way to evaluate tsunami risk using a response

  3. NOAA/West coast and Alaska Tsunami warning center Atlantic Ocean response criteria

    Science.gov (United States)

    Whitmore, P.; Refidaff, C.; Caropolo, M.; Huerfano-Moreno, V.; Knight, W.; Sammler, W.; Sandrik, A.

    2009-01-01

    West Coast/Alaska Tsunami Warning Center (WCATWC) response criteria for earthquakesoccurring in the Atlantic and Caribbean basins are presented. Initial warning center decisions are based on an earthquake's location, magnitude, depth, distance from coastal locations, and precomputed threat estimates based on tsunami models computed from similar events. The new criteria will help limit the geographical extent of warnings and advisories to threatened regions, and complement the new operational tsunami product suite. Criteria are set for tsunamis generated by earthquakes, which are by far the main cause of tsunami generation (either directly through sea floor displacement or indirectly by triggering of sub-sea landslides).The new criteria require development of a threat data base which sets warning or advisory zones based on location, magnitude, and pre-computed tsunami models. The models determine coastal tsunami amplitudes based on likely tsunami source parameters for a given event. Based on the computed amplitude, warning and advisory zones are pre-set.

  4. Real-time forecasting of the April 11, 2012 Sumatra tsunami

    Science.gov (United States)

    Wang, Dailin; Becker, Nathan C.; Walsh, David; Fryer, Gerard J.; Weinstein, Stuart A.; McCreery, Charles S.; ,

    2012-01-01

    The April 11, 2012, magnitude 8.6 earthquake off the northern coast of Sumatra generated a tsunami that was recorded at sea-level stations as far as 4800 km from the epicenter and at four ocean bottom pressure sensors (DARTs) in the Indian Ocean. The governments of India, Indonesia, Sri Lanka, Thailand, and Maldives issued tsunami warnings for their coastlines. The United States' Pacific Tsunami Warning Center (PTWC) issued an Indian Ocean-wide Tsunami Watch Bulletin in its role as an Interim Service Provider for the region. Using an experimental real-time tsunami forecast model (RIFT), PTWC produced a series of tsunami forecasts during the event that were based on rapidly derived earthquake parameters, including initial location and Mwp magnitude estimates and the W-phase centroid moment tensor solutions (W-phase CMTs) obtained at PTWC and at the U. S. Geological Survey (USGS). We discuss the real-time forecast methodology and how successive, real-time tsunami forecasts using the latest W-phase CMT solutions improved the accuracy of the forecast.

  5. A culture of tsunami preparedness and applying knowledge from recent tsunamis affecting California

    Science.gov (United States)

    Miller, K. M.; Wilson, R. I.

    2012-12-01

    It is the mission of the California Tsunami Program to ensure public safety by protecting lives and property before, during, and after a potentially destructive or damaging tsunami. In order to achieve this goal, the state has sought first to use finite funding resources to identify and quantify the tsunami hazard using the best available scientific expertise, modeling, data, mapping, and methods at its disposal. Secondly, it has been vital to accurately inform the emergency response community of the nature of the threat by defining inundation zones prior to a tsunami event and leveraging technical expertise during ongoing tsunami alert notifications (specifically incoming wave heights, arrival times, and the dangers of strong currents). State scientists and emergency managers have been able to learn and apply both scientific and emergency response lessons from recent, distant-source tsunamis affecting coastal California (from Samoa in 2009, Chile in 2010, and Japan in 2011). Emergency managers must understand and plan in advance for specific actions and protocols for each alert notification level provided by the NOAA/NWS West Coast/Alaska Tsunami Warning Center. Finally the state program has provided education and outreach information via a multitude of delivery methods, activities, and end products while keeping the message simple, consistent, and focused. The goal is a culture of preparedness and understanding of what to do in the face of a tsunami by residents, visitors, and responsible government officials. We provide an update of results and findings made by the state program with support of the National Tsunami Hazard Mitigation Program through important collaboration with other U.S. States, Territories and agencies. In 2009 the California Emergency Management Agency (CalEMA) and the California Geological Survey (CGS) completed tsunami inundation modeling and mapping for all low-lying, populated coastal areas of California to assist local jurisdictions on

  6. Posttraumatic symptoms in elementary and junior high school children after the 2011 Japan earthquake and tsunami: symptom severity and recovery vary by age and sex.

    Science.gov (United States)

    Iwadare, Yoshitaka; Usami, Masahide; Suzuki, Yuriko; Ushijima, Hirokage; Tanaka, Tetsuya; Watanabe, Kyota; Kodaira, Masaki; Saito, Kazuhiko

    2014-04-01

    To measure psychiatric symptoms exhibited by children in Ishinomaki City, Japan, an area severely damaged by the 2011 earthquake and tsunami, at 8 and 20 months post-tsunami to investigate differences in symptom severity and recovery rate by age, sex, and degree of trauma experienced. Prospective data were collected from children in elementary school (5th and 6th grades) and junior high school (8th and 9th grades). Students completed the Post-Traumatic Stress Symptoms for Children-15 (PTSSC-15) survey. Trauma severity was scored according to experiences of bereavement, home damage, and evacuation. In total, 3795 PTSSC-15 surveys were analyzed, yielding total scores, post-traumatic stress disorder (PTSD) factor subscores, and depression factor subscores, which were analyzed according to grade group, sex, and degree of trauma (trauma dose). In the elementary school children, mean total PTSSC-15 score, PTSD factor score, and depression factor score were significantly improved at 20 months post-tsunami compared with 8 months (P junior high school children. In females of the older group, the depression factor score at 20 months post-tsunami was significantly higher than at 8 months (P Elementary school and junior high school children living near the epicenter of the 2011 Japan earthquake and tsunami exhibited marked differences in PTSD and depressive symptoms. The mental health status of elementary school children improved, whereas that of junior high school children did not. Crown Copyright © 2014. Published by Mosby, Inc. All rights reserved.

  7. U.S. Tsunami Information technology (TIM) Modernization:Developing a Maintainable and Extensible Open Source Earthquake and Tsunami Warning System

    Science.gov (United States)

    Hellman, S. B.; Lisowski, S.; Baker, B.; Hagerty, M.; Lomax, A.; Leifer, J. M.; Thies, D. A.; Schnackenberg, A.; Barrows, J.

    2015-12-01

    Tsunami Information technology Modernization (TIM) is a National Oceanic and Atmospheric Administration (NOAA) project to update and standardize the earthquake and tsunami monitoring systems currently employed at the U.S. Tsunami Warning Centers in Ewa Beach, Hawaii (PTWC) and Palmer, Alaska (NTWC). While this project was funded by NOAA to solve a specific problem, the requirements that the delivered system be both open source and easily maintainable have resulted in the creation of a variety of open source (OS) software packages. The open source software is now complete and this is a presentation of the OS Software that has been funded by NOAA for benefit of the entire seismic community. The design architecture comprises three distinct components: (1) The user interface, (2) The real-time data acquisition and processing system and (3) The scientific algorithm library. The system follows a modular design with loose coupling between components. We now identify the major project constituents. The user interface, CAVE, is written in Java and is compatible with the existing National Weather Service (NWS) open source graphical system AWIPS. The selected real-time seismic acquisition and processing system is open source SeisComp3 (sc3). The seismic library (libseismic) contains numerous custom written and wrapped open source seismic algorithms (e.g., ML/mb/Ms/Mwp, mantle magnitude (Mm), w-phase moment tensor, bodywave moment tensor, finite-fault inversion, array processing). The seismic library is organized in a way (function naming and usage) that will be familiar to users of Matlab. The seismic library extends sc3 so that it can be called by the real-time system, but it can also be driven and tested outside of sc3, for example, by ObsPy or Earthworm. To unify the three principal components we have developed a flexible and lightweight communication layer called SeismoEdex.

  8. A BRIEF HISTORY OF TSUNAMIS IN THE CARIBBEAN SEA

    Directory of Open Access Journals (Sweden)

    Patricia A. Lockridge

    2002-01-01

    Full Text Available The area of the Caribbean Sea is geologically active. Earthquakes and volcanoes are common occurrences. These geologic events can generate powerful tsunamis some of which are more devastating than the earthquake or volcanic eruption itself. This document lists brief descriptions of 91 reported waves that might have been tsunamis within the Caribbean region. Of these, 27 are judged by the authors to be true, verified tsunamis and an additional nine are considered to be very likely true tsunamis. The additional 53 events either are not described with sufficient detail in the literature to verify their tsunami nature or are judged to be reports of other phenomenasuch as sea quakes or hurricane storm surges which may have been reported as tsunamis. Included in these 91 reports are teletsunamis, tectonic tsunamis, landslide tsunamis, and volcanic tsunamis that have caused major damage and deaths. Nevertheless, in recent history these events have been relatively rare. In the interim since the last major tsunami event in the Caribbean Sea the coastal regions have greatly increased in population. Coastal development has also increased. Today tourism is a major industry that exposes thousands of non-residents to the disastrous effects of a tsunami. These factors make the islands in this region much more vulnerable today than they were when the last major tsunami occurred in this area. This paper gives an overview of the tsunami history in the area. This history illustrates what can be expected in the future from this geologic hazard and provides information that will be useful for mitigation purposes.

  9. Sensitivity of the coastal tsunami simulation to the complexity of the 2011 Tohoku earthquake source model

    Science.gov (United States)

    Monnier, Angélique; Loevenbruck, Anne; Gailler, Audrey; Hébert, Hélène

    2016-04-01

    The 11 March 2011 Tohoku-Oki event, whether earthquake or tsunami, is exceptionally well documented. A wide range of onshore and offshore data has been recorded from seismic, geodetic, ocean-bottom pressure and sea level sensors. Along with these numerous observations, advance in inversion technique and computing facilities have led to many source studies. Rupture parameters inversion such as slip distribution and rupture history permit to estimate the complex coseismic seafloor deformation. From the numerous published seismic source studies, the most relevant coseismic source models are tested. The comparison of the predicted signals generated using both static and cinematic ruptures to the offshore and coastal measurements help determine which source model should be used to obtain the more consistent coastal tsunami simulations. This work is funded by the TANDEM project, reference ANR-11-RSNR-0023-01 of the French Programme Investissements d'Avenir (PIA 2014-2018).

  10. A 600-year-long stratigraphic record of tsunamis in south-central Chile

    Science.gov (United States)

    Hong, Isabel; Dura, Tina; Ely, Lisa L.; Horton, Benajamin P.; Nelson, Alan R.; Cisternas, Marco; Nikitina, Daria; Wesson, Robert L.

    2017-01-01

    The stratigraphy within coastal river valleys in south-central Chile clarifies and extends the region’s history of large, earthquakes and accompanying tsunamis. Our site at Quidico (38.1°S, 73.3°W) is located in an overlap zone between ruptures of magnitude 8–9 earthquakes in 1960 and 2010, and, therefore, records tsunamis originating from subduction-zone ruptures north and south of the city of Concepción. Hand-dug pits and cores in a 3-m-thick sequence of freshwater peat in an abandoned meander (a little-examined depositional environment for tsunami deposits) and exposures along the Quidico River show five sand beds that extend as much as 1.2 km inland. Evidence for deposition of the beds by tsunamis includes tabular sand beds that are laterally extensive (>100 m), well sorted, fine upward, have sharp lower contacts, and contain diatom assemblages dominated by brackish and marine taxa. Using eyewitness accounts of tsunami inundation, 137Cs analyses, and 14C dating, we matched the upper four sand beds with historical tsunamis in 2010, 1960, 1835, and 1751. The oldest prehistoric bed dates to 1445–1490 CE and correlates with lacustrine and coastal records of similar-aged earthquakes and tsunamis in south-central Chile.

  11. Field survey of the 16 September 2015 Chile tsunami

    Science.gov (United States)

    Lagos, Marcelo; Fritz, Hermann M.

    2016-04-01

    On the evening of 16 September, 2015 a magnitude Mw 8.3 earthquake occurred off the coast of central Chile's Coquimbo region. The ensuing tsunami caused significant inundation and damage in the Coquimbo or 4th region and mostly minor effects in neighbouring 3rd and 5th regions. Fortunately, ancestral knowledge from the past 1922 and 1943 tsunamis in the region along with the catastrophic 2010 Maule and recent 2014 tsunamis, as well as tsunami education and evacuation exercises prompted most coastal residents to spontaneously evacuate to high ground after the earthquake. There were a few tsunami victims; while a handful of fatalities were associated to earthquake induced building collapses and the physical stress of tsunami evacuation. The international scientist joined the local effort from September 20 to 26, 2015. The international tsunami survey team (ITST) interviewed numerous eyewitnesses and documented flow depths, runup heights, inundation distances, sediment deposition, damage patterns, performance of the navigation infrastructure and impact on the natural environment. The ITST covered a 500 km stretch of coastline from Caleta Chañaral de Aceituno (28.8° S) south of Huasco down to Llolleo near San Antonio (33.6° S). We surveyed more than 40 locations and recorded more than 100 tsunami and runup heights with differential GPS and integrated laser range finders. The tsunami impact peaked at Caleta Totoral near Punta Aldea with both tsunami and runup heights exceeding 10 m as surveyed on September 22 and broadcasted nationwide that evening. Runup exceeded 10 m at a second uninhabited location some 15 km south of Caleta Totoral. A significant variation in tsunami impact was observed along the coastlines of central Chile at local and regional scales. The tsunami occurred in the evening hours limiting the availability of eyewitness video footages. Observations from the 2015 Chile tsunami are compared against the 1922, 1943, 2010 and 2014 Chile tsunamis. The

  12. Amplification of drawdown and runup over Hawaii's insular shelves by tsunami N-waves from mega Aleutian earthquakes

    Science.gov (United States)

    Bai, Yefei; Yamazaki, Yoshiki; Cheung, Kwok Fai

    2018-04-01

    The latest tsunami evacuation maps of Hawaii include an extreme scenario triggered by an Mw 9.3 Aleutian earthquake with large near-trench rupture. The tectonic plate motion produces concentrated seafloor uplift toward the deepest part of the trench generating a tsunami with strong non-hydrostatic characters. A parametric study shows the skewed seafloor uplift produces a dispersive leading crest followed by a prominent trough in the form of an N-wave. The trough maintains its depth across the ocean in the absence of side lobes and dispersion. Shifting of the uplift toward the trench tends to deepen the trough, but has diminishing effects on the wave crest away from the source. While the attenuated leading crest produces relatively moderate runup on north-facing shores of the Hawaiian Islands, with matching of the N-wave and shelf resonance periods, the trough produces an impulsive drawdown followed by an energetic upswing with unprecedented runup for a far-field tsunami. A set of control computations without dispersion reaffirms that a non-hydrostatic model is essential to account for these complex wave processes from the source to the shore. This case study highlights the unique tsunami hazards posed by the Aleutians to Hawaii and the role of wave troughs in delineating the impacts for hazard assessment and engineering design.

  13. On The Source Of The 25 November 1941 - Atlantic Tsunami

    Science.gov (United States)

    Baptista, M. A.; Lisboa, F. B.; Miranda, J. M. A.

    2015-12-01

    In this study we analyze the tsunami recorded in the North Atlantic following the 25 November 1941 earthquake. The earthquake with a magnitude of 8.3, located on the Gloria Fault, was one of the largest strike slip events recorded. The Gloria fault is a 500 km long scarp in the North Atlantic Ocean between 19W and 24W known to be a segment of the Eurasia-Nubia plate boundary between Iberia and the Azores. Ten tide stations recorded the tsunami. Six in Portugal (mainland, Azores and Madeira Islands), two in Morocco, one in the United Kingdom and one in Spain (Tenerife-Canary Islands). The tsunami waves reached Azores and Madeira Islands less than one hour after the main shock. The tide station of Casablanca (in Morocco) recorded the maximum amplitude of 0.54 m. All amplitudes recorded are lower than 0.5 m but the tsunami reached Portugal mainland in high tide conditions where the sea flooded some streets We analyze the 25 November 1941 tsunami data using the tide-records in the coasts of Portugal, Spain, Morocco and UK to infer its source. The use of wavelet analysis to characterize the frequency content of the tide-records shows predominant periods of 9-13min e 18-22min. A preliminary location of the tsunami source location was obtained Backward Ray Tracing (BRT). The results of the BRT technique are compatible with the epicenter location of the earthquake. We compute empirical Green functions for the earthquake generation area, and use a linear shallow water inversion technique to compute the initial water displacement. The comparison between forward modeling with observations shows a fair agreement with available data. This work received funding from the European Union's Seventh Framework Programme (FP7/2007-2013) under grant agreement n° 603839 (Project ASTARTE - Assessment, Strategy and Risk Reduction for Tsunamis in Europe)"

  14. Tsunamis: stochastic models of occurrence and generation mechanisms

    Science.gov (United States)

    Geist, Eric L.; Oglesby, David D.

    2014-01-01

    The devastating consequences of the 2004 Indian Ocean and 2011 Japan tsunamis have led to increased research into many different aspects of the tsunami phenomenon. In this entry, we review research related to the observed complexity and uncertainty associated with tsunami generation, propagation, and occurrence described and analyzed using a variety of stochastic methods. In each case, seismogenic tsunamis are primarily considered. Stochastic models are developed from the physical theories that govern tsunami evolution combined with empirical models fitted to seismic and tsunami observations, as well as tsunami catalogs. These stochastic methods are key to providing probabilistic forecasts and hazard assessments for tsunamis. The stochastic methods described here are similar to those described for earthquakes (Vere-Jones 2013) and volcanoes (Bebbington 2013) in this encyclopedia.

  15. Assessment of the Initial Response from Tsunami Monitoring Services Provided to the Northeastern Caribbean

    Science.gov (United States)

    Soto-Cordero, L.; Meltzer, A.

    2014-12-01

    A mag 6.4 earthquake offshore northern Puerto Rico earlier this year (1/13/14) is a reminder of the high risk of earthquakes and tsunamis in the northeastern Caribbean. Had the magnitude of this event been 0.1 larger (M 6.5) a tsunami warning would have been issued for the Puerto Rico-Virgin Islands (PRVI) region based on the West Coast Alaska Tsunami Warning Center (WCATWC) and Puerto Rico Seismic Network (PRSN) response procedures at the time. Such an alert level would have led local authorities to issue evacuation orders for all PRVI coastal areas. Since the number of deaths associated with tsunamis in the Caribbean region is greater than the total casualties from tsunamis in the entire US (including Hawaii and Alaska coasts) having an effective and redundant warning system is critical in order to save lives and to minimize false alarms that could result in significant economic costs and loss of confidence of Caribbean residents. We are evaluating three fundamental components of tsunami monitoring protocols currently in place in the northeastern Caribbean: 1) preliminary earthquake parameters (used to determine the potential that a tsunami will be generated and the basis of tsunami alert levels), 2) adequacy of the tsunami alert levels, and 3) tsunami message dissemination. We compiled a catalog of earthquake locations (2007-2014) and dissemination times from the PTWC, WCATWC and NEIC (final locations). The events were classified into 3 categories: local [17°-20°N, 63.5°-69°W], regional (Caribbean basin) and distant/teleseismic (Atlantic basin). A total of 104 local earthquakes, 31 regional and 25 distant events were analyzed. We found that in general preliminary epicentral locations have an accuracy of 40 km. 64% of local events were located with an accuracy of 20 km. The depth accuracy of local events shallower than 50 km, regional and distant earthquakes is usually smaller than 30 km. For deeper local events the error distribution shows more variability

  16. Near Field Modeling for the Maule Tsunami from DART, GPS and Finite Fault Solutions (Invited)

    Science.gov (United States)

    Arcas, D.; Chamberlin, C.; Lagos, M.; Ramirez-Herrera, M.; Tang, L.; Wei, Y.

    2010-12-01

    The earthquake and tsunami of February, 27, 2010 in central Chile has rekindled an interest in developing techniques to predict the impact of near field tsunamis along the Chilean coastline. Following the earthquake, several initiatives were proposed to increase the density of seismic, pressure and motion sensors along the South American trench, in order to provide field data that could be used to estimate tsunami impact on the coast. However, the precise use of those data in the elaboration of a quantitative assessment of coastal tsunami damage has not been clarified. The present work makes use of seismic, Deep-ocean Assessment and Reporting of Tsunamis (DART®) systems, and GPS measurements obtained during the Maule earthquake to initiate a number of tsunami inundation models along the rupture area by expressing different versions of the seismic crustal deformation in terms of NOAA’s tsunami unit source functions. Translation of all available real-time data into a feasible tsunami source is essential in near-field tsunami impact prediction in which an impact assessment must be generated under very stringent time constraints. Inundation results from each different source are then contrasted with field and tide gauge data by comparing arrival time, maximum wave height, maximum inundation and tsunami decay rate, using field data collected by the authors.

  17. Seismic and tsunami safety margin assessment

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2013-08-15

    Nuclear Regulation Authority is going to establish new seismic and tsunami safety guidelines to increase the safety of NPPs. The main purpose of this research is testing structures/components important to safety and tsunami resistant structures/components, and evaluating the capacity of them against earthquake and tsunami. Those capacity data will be utilized for the seismic and tsunami back-fit review based on the new seismic and tsunami safety guidelines. The summary of the program in 2012 is as follows. 1. Component seismic capacity test and quantitative seismic capacity evaluation. PWR emergency diesel generator partial-model seismic capacity tests have been conducted and quantitative seismic capacities have been evaluated. 2. Seismic capacity evaluation of switching-station electric equipment. Existing seismic test data investigation, specification survey and seismic response analyses have been conducted. 3. Tsunami capacity evaluation of anti-inundation measure facilities. Tsunami pressure test have been conducted utilizing a small breakwater model and evaluated basic characteristics of tsunami pressure against seawall structure. (author)

  18. Seismic and tsunami safety margin assessment

    International Nuclear Information System (INIS)

    2013-01-01

    Nuclear Regulation Authority is going to establish new seismic and tsunami safety guidelines to increase the safety of NPPs. The main purpose of this research is testing structures/components important to safety and tsunami resistant structures/components, and evaluating the capacity of them against earthquake and tsunami. Those capacity data will be utilized for the seismic and tsunami back-fit review based on the new seismic and tsunami safety guidelines. The summary of the program in 2012 is as follows. 1. Component seismic capacity test and quantitative seismic capacity evaluation. PWR emergency diesel generator partial-model seismic capacity tests have been conducted and quantitative seismic capacities have been evaluated. 2. Seismic capacity evaluation of switching-station electric equipment. Existing seismic test data investigation, specification survey and seismic response analyses have been conducted. 3. Tsunami capacity evaluation of anti-inundation measure facilities. Tsunami pressure test have been conducted utilizing a small breakwater model and evaluated basic characteristics of tsunami pressure against seawall structure. (author)

  19. Tsunami Modeling and Prediction Using a Data Assimilation Technique with Kalman Filters

    Science.gov (United States)

    Barnier, G.; Dunham, E. M.

    2016-12-01

    Earthquake-induced tsunamis cause dramatic damages along densely populated coastlines. It is difficult to predict and anticipate tsunami waves in advance, but if the earthquake occurs far enough from the coast, there may be enough time to evacuate the zones at risk. Therefore, any real-time information on the tsunami wavefield (as it propagates towards the coast) is extremely valuable for early warning systems. After the 2011 Tohoku earthquake, a dense tsunami-monitoring network (S-net) based on cabled ocean-bottom pressure sensors has been deployed along the Pacific coast in Northeastern Japan. Maeda et al. (GRL, 2015) introduced a data assimilation technique to reconstruct the tsunami wavefield in real time by combining numerical solution of the shallow water wave equations with additional terms penalizing the numerical solution for not matching observations. The penalty or gain matrix is determined though optimal interpolation and is independent of time. Here we explore a related data assimilation approach using the Kalman filter method to evolve the gain matrix. While more computationally expensive, the Kalman filter approach potentially provides more accurate reconstructions. We test our method on a 1D tsunami model derived from the Kozdon and Dunham (EPSL, 2014) dynamic rupture simulations of the 2011 Tohoku earthquake. For appropriate choices of model and data covariance matrices, the method reconstructs the tsunami wavefield prior to wave arrival at the coast. We plan to compare the Kalman filter method to the optimal interpolation method developed by Maeda et al. (GRL, 2015) and then to implement the method for 2D.

  20. Source fault model of the 2011 off the pacific coast of Tohoku Earthquake, estimated from the detailed distribution of tsunami run-up heights

    International Nuclear Information System (INIS)

    Matsuta, Nobuhisa; Suzuki, Yasuhiro; Sugito, Nobuhiko; Nakata, Takashi; Watanabe, Mitsuhisa

    2015-01-01

    The distribution of tsunami run-up heights generally has spatial variations, because run-up heights are controlled by coastal topography including local-scale landforms such as natural levees, in addition to land use. Focusing on relationships among coastal topography, land conditions, and tsunami run-up heights of historical tsunamis—Meiji Sanriku (1896 A.D.), Syowa Sanriku (1933 A.D.), and Chilean Sanriku (1960 A.D.) tsunamis—along the Sanriku coast, it is found that the wavelength of a tsunami determines inundation areas as well as run-up heights. Small bays facing the Pacific Ocean are sensitive to short wavelength tsunamis, and large bays are sensitive to long wavelength tsunamis. The tsunami observed off Kamaishi during the 2011 off the Pacific coast of Tohoku Earthquake was composed of both short and long wavelength components. We examined run-up heights of the Tohoku tsunami, and found that: (1) coastal areas north of Kamaishi and south of Yamamoto were mainly attacked by short wavelength tsunamis; and (2) no evidence of short wavelength tsunamis was observed from Ofunato to the Oshika Peninsula. This observation coincides with the geomorphologically proposed source fault model, and indicates that the extraordinary large slip along the shallow part of the plate boundary off Sendai, proposed by seismological and geodesic analyses, is not needed to explain the run-up heights of the Tohoku tsunami. To better understand spatial variations of tsunami run-up heights, submarine crustal movements, and source faults, a detailed analysis is required of coastal topography, land conditions, and submarine tectonic landforms from the perspective of geomorphology. (author)

  1. Weight Gain in Survivors Living in Temporary Housing in the Tsunami-Stricken Area during the Recovery Phase following the Great East Japan Earthquake and Tsunami.

    Science.gov (United States)

    Takahashi, Shuko; Yonekura, Yuki; Sasaki, Ryohei; Yokoyama, Yukari; Tanno, Kozo; Sakata, Kiyomi; Ogawa, Akira; Kobayashi, Seichiro; Yamamoto, Taro

    2016-01-01

    Survivors who lost their homes in the Great East Japan Earthquake and Tsunami were forced to live in difficult conditions in temporary housing several months after the disaster. Body weights of survivors living in temporary housing for a long period might increase due to changes in their life style and psychosocial state during the medium-term and long-term recovery phases. The aim of this study was to determine whether there were differences between body weight changes of people living in temporary housing and those not living in temporary housing in a tsunami-stricken area during the medium-term and long-term recovery phases. Health check-ups were performed about 7 months after the disaster (in 2011) and about 18 months after the disaster (in 2012) for people living in a tsunami-stricken area (n = 6,601, mean age = 62.3 y). We compared the changes in body weight in people living in temporary housing (TH group, n = 2,002) and those not living in temporary housing (NTH group, n = 4,599) using a multiple linear regression model. While there was no significant difference between body weights in the TH and NTH groups in the 2011 survey, there was a significant difference between the mean changes in body weight in both sexes. We found that the changes in body weight were significantly greater in the TH group than in the NTH group in both sexes. The partial regression coefficients of mean change in body weight were +0.52 kg (P-value tsunami- stricken area had a significant increase in body weight.

  2. Assessing historical rate changes in global tsunami occurrence

    Science.gov (United States)

    Geist, E.L.; Parsons, T.

    2011-01-01

    The global catalogue of tsunami events is examined to determine if transient variations in tsunami rates are consistent with a Poisson process commonly assumed for tsunami hazard assessments. The primary data analyzed are tsunamis with maximum sizes >1m. The record of these tsunamis appears to be complete since approximately 1890. A secondary data set of tsunamis >0.1m is also analyzed that appears to be complete since approximately 1960. Various kernel density estimates used to determine the rate distribution with time indicate a prominent rate change in global tsunamis during the mid-1990s. Less prominent rate changes occur in the early- and mid-20th century. To determine whether these rate fluctuations are anomalous, the distribution of annual event numbers for the tsunami catalogue is compared to Poisson and negative binomial distributions, the latter of which includes the effects of temporal clustering. Compared to a Poisson distribution, the negative binomial distribution model provides a consistent fit to tsunami event numbers for the >1m data set, but the Poisson null hypothesis cannot be falsified for the shorter duration >0.1m data set. Temporal clustering of tsunami sources is also indicated by the distribution of interevent times for both data sets. Tsunami event clusters consist only of two to four events, in contrast to protracted sequences of earthquakes that make up foreshock-main shock-aftershock sequences. From past studies of seismicity, it is likely that there is a physical triggering mechanism responsible for events within the tsunami source 'mini-clusters'. In conclusion, prominent transient rate increases in the occurrence of global tsunamis appear to be caused by temporal grouping of geographically distinct mini-clusters, in addition to the random preferential location of global M >7 earthquakes along offshore fault zones.

  3. Optimum Sea Surface Displacement and Fault Slip Distribution of the 2017 Tehuantepec Earthquake (Mw 8.2) in Mexico Estimated From Tsunami Waveforms

    Science.gov (United States)

    Gusman, Aditya Riadi; Mulia, Iyan E.; Satake, Kenji

    2018-01-01

    The 2017 Tehuantepec earthquake (Mw 8.2) was the first great normal fault event ever instrumentally recorded to occur in the Middle America Trench. The earthquake generated a tsunami with an amplitude of 1.8 m (height = 3.5 m) in Puerto Chiapas, Mexico. Tsunami waveforms recorded at coastal tide gauges and offshore buoy stations were used to estimate the optimum sea surface displacement without assuming any fault. Our optimum sea surface displacement model indicated that the maximum uplift of 0.5 m is located near the trench and the maximum subsidence of 0.8 m on the coastal side near the epicenter. We then estimated the fault slip distribution that can best explain the optimum sea surface displacement assuming 10 different fault geometries. The best model suggests that a compact region of large slip (3-6 m) extends from a depth of 30 km to 90 km, centered at a depth of 60 km.

  4. Highly variable recurrence of tsunamis in the 7,400 years before the 2004 Indian Ocean tsunami.

    Science.gov (United States)

    Rubin, Charles M; Horton, Benjamin P; Sieh, Kerry; Pilarczyk, Jessica E; Daly, Patrick; Ismail, Nazli; Parnell, Andrew C

    2017-07-19

    The devastating 2004 Indian Ocean tsunami caught millions of coastal residents and the scientific community off-guard. Subsequent research in the Indian Ocean basin has identified prehistoric tsunamis, but the timing and recurrence intervals of such events are uncertain. Here we present an extraordinary 7,400 year stratigraphic sequence of prehistoric tsunami deposits from a coastal cave in Aceh, Indonesia. This record demonstrates that at least 11 prehistoric tsunamis struck the Aceh coast between 7,400 and 2,900 years ago. The average time period between tsunamis is about 450 years with intervals ranging from a long, dormant period of over 2,000 years, to multiple tsunamis within the span of a century. Although there is evidence that the likelihood of another tsunamigenic earthquake in Aceh province is high, these variable recurrence intervals suggest that long dormant periods may follow Sunda megathrust ruptures as large as that of the 2004 Indian Ocean tsunami.

  5. Field Survey of the 2015 Ilapel Tsunami in North Central Chile

    Science.gov (United States)

    Lagos, M.; Fritz, H. M.

    2016-12-01

    The magnitude Mw 8.3 earthquake in north-central Chile on September 16, 2015 generated a tsunami that rapidly flooded coastal areas. The tsunami impact was concentrated in Coquimbo region, while the regions of Valparaiso and Atacama were also affected. Fortunately, ancestral knowledge from the past tsunamis in the region, as well as tsunami education and evacuation exercises prompted most coastal residents to spontaneously evacuate to high ground after the earthquake. The event caused 11 fatalities: 8 were associated with the tsunami, while 3 were attributed to building collapses caused by the earthquake. The international scientist joined the local effort from September 20 to 26, 2015. The international tsunami survey team (ITST) interviewed numerous eyewitnesses and documented flow depths, runup heights, inundation distances, sediment deposition, damage patterns, performance of the navigation infrastructure and impact on the natural environment. The ITST covered a 500 km stretch of coastline from Caleta Chañaral de Aceituno (28.8° S) south of Huasco down to Llolleo near San Antonio (33.6° S). We surveyed more than 40 locations and recorded more than 100 tsunami and runup heights with differential GPS and integrated laser range finders. The tsunami impact peaked at Caleta Totoral near Punta Aldea with both tsunami and runup heights exceeding 10 m as surveyed on September 22. Runup exceeded 10 m at a second uninhabited location some 15 km south of Caleta Totoral. A significant variation in tsunami impact was observed along the coastlines of central Chile at local and regional scales. The tsunami occurred in the evening hours limiting the availability of eyewitness video footages. Observations from the 2015 Chile tsunami are compared with recent Chilean tsunamis. The tsunami was characterized by rapid arrival within minutes in the nearfield requiring spontaneous self-evacuation as warning messages did not reach some of the hardest hit fishing villages prior to

  6. Source mechanisms of volcanic tsunamis.

    Science.gov (United States)

    Paris, Raphaël

    2015-10-28

    Volcanic tsunamis are generated by a variety of mechanisms, including volcano-tectonic earthquakes, slope instabilities, pyroclastic flows, underwater explosions, shock waves and caldera collapse. In this review, we focus on the lessons that can be learnt from past events and address the influence of parameters such as volume flux of mass flows, explosion energy or duration of caldera collapse on tsunami generation. The diversity of waves in terms of amplitude, period, form, dispersion, etc. poses difficulties for integration and harmonization of sources to be used for numerical models and probabilistic tsunami hazard maps. In many cases, monitoring and warning of volcanic tsunamis remain challenging (further technical and scientific developments being necessary) and must be coupled with policies of population preparedness. © 2015 The Author(s).

  7. Characteristics of Recent Tsunamis

    Science.gov (United States)

    Sweeney, A. D.; Eble, M. C.; Mungov, G.

    2017-12-01

    How long do tsunamis impact a coast? How often is the largest tsunami wave the first to arrive? How do measurements in the far field differ from those made close to the source? Extending the study of Eblé et al. (2015) who showed the prevalence of a leading negative phase, we assimilate and summarize characteristics of known tsunami events recorded on bottom pressure and coastal water level stations throughout the world oceans to answer these and other questions. An extensive repository of data from the National Centers for Environmental Information (NCEI) archive for tsunami-ready U.S. tide gauge stations, housing more than 200 sites going back 10 years are utilized as are some of the more 3000 marigrams (analog or paper tide gauge records) for tsunami events. The focus of our study is on five tsunamis generated by earthquakes: 2010 Chile (Maule), 2011 East Japan (Tohoku), 2012 Haida Gwaii, 2014 Chile (Iquique), and 2015 Central Chile and one meteorologically generated tsunami on June 2013 along the U.S. East Coast and Caribbean. Reference: Eblé, M., Mungov, G. & Rabinovich, A. On the Leading Negative Phase of Major 2010-2014 Tsunamis. Pure Appl. Geophys. (2015) 172: 3493. https://doi.org/10.1007/s00024-015-1127-5

  8. Trauma, depression, and resilience of earthquake/tsunami/nuclear disaster survivors of Hirono, Fukushima, Japan.

    Science.gov (United States)

    Kukihara, Hiroko; Yamawaki, Niwako; Uchiyama, Kumi; Arai, Shoichi; Horikawa, Etsuo

    2014-07-01

    A mega-earthquake and tsunami struck the northeastern coast of Japan, and many survivors were forced to evacuate to temporary housing due to rising radiation levels. The aims of this study were to investigate the prevalence of symptoms of post-traumatic stress disorder (PTSD), depression, and poor general health among survivors, to test the predictive roles of resilience on mental and physical health, and to examine the predictive sociodemographic factors on resilience. Two hundred and forty-one evacuees (men/women: 116/125) from Hirono, Fukushima participated in the study. They were asked to complete the Connor-Davidson Resilience Scale, the Zung Self-Rating Depression Scale, the Impact of Events Scale-Revised, and a demographic questionnaire. Among all participants, 53.5% exhibited the clinically concerning symptoms of PTSD, and among them 33.2% indicated clinical PTSD symptoms. Additionally, 66.8% reported symptoms of depression, and among them 33.2% showed mildly depressive symptoms, while 19.1% and 14.5% demonstrated moderate and severe depressive symptoms, respectively. Resilience was a significant buffer for depression, PTSD, and general health. Additionally, employment status, eating/exercise habits, and drinking habits predicted resilience. The results indicated that depression and PTSD are prevalent among the survivors of massive earthquakes, tsunamis, and accidents from nuclear power plants. However, the results also showed that some survivors managed to endure the traumatic events relatively well, and resilience was a significant protective factor in dealing with such events. Therefore, it is crucial to assist survivors in improving their resilience by providing job opportunities and encouraging a healthy lifestyle. © 2014 The Authors. Psychiatry and Clinical Neurosciences © 2014 Japanese Society of Psychiatry and Neurology.

  9. Wavelet analysis of the seismograms for tsunami warning

    Directory of Open Access Journals (Sweden)

    A. Chamoli

    2010-10-01

    Full Text Available The complexity in the tsunami phenomenon makes the available warning systems not much effective in the practical situations. The problem arises due to the time lapsed in the data transfer, processing and modeling. The modeling and simulation needs the input fault geometry and mechanism of the earthquake. The estimation of these parameters and other aprior information increases the utilized time for making any warning. Here, the wavelet analysis is used to identify the tsunamigenesis of an earthquake. The frequency content of the seismogram in time scale domain is examined using wavelet transform. The energy content in high frequencies is calculated and gives a threshold for tsunami warnings. Only first few minutes of the seismograms of the earthquake events are used for quick estimation. The results for the earthquake events of Andaman Sumatra region and other historic events are promising.

  10. Revision of the tsunami catalogue affecting Turkish coasts and surrounding regions

    Directory of Open Access Journals (Sweden)

    Y. Altinok

    2011-02-01

    Full Text Available The coasts of Turkey have been hit by tsunamis in the past. The first national earthquake-tsunami catalogues were compiled in the early 1980s while the most up-to-date tsunami catalogues are mainly the products of recent European projects. The EU projects GITEC and GITEC-TWO (Genesis and Impact of Tsunamis on the European Coasts and TRANSFER (Tsunami Risk ANd Strategies For the European Region have added important contributions in establishing and developing unified criteria for tsunami parameterisation, standards for the quality of the data, the data format and the database general architecture. On the basis of these new aspects and based on recent marine geophysical data, tsunamigenic earthquakes, tsunami intensities and their reliability have been revised. The current version of the database contains 134 events, most of which have affected the Turkish coasts seriously during the last 3500 years. The reliability index of 76 events was "probable" and "definite", so that they could be used for assessment of the risk along the Turkish coastal region and for implementation of prevention policies.

  11. Performance of coastal sea-defense infrastructure at El Jadida (Morocco against tsunami threat: lessons learned from the Japanese 11 March 2011 tsunami

    Directory of Open Access Journals (Sweden)

    R. Omira

    2013-07-01

    Full Text Available This paper seeks to investigate the effectiveness of sea-defense structures in preventing/reducing the tsunami overtopping as well as evaluating the resulting tsunami impact at El Jadida, Morocco. Different tsunami wave conditions are generated by considering various earthquake scenarios of magnitudes ranging from Mw = 8.0 to Mw = 8.6. These scenarios represent the main active earthquake faults in the SW Iberia margin and are consistent with two past events that generated tsunamis along the Atlantic coast of Morocco. The behaviour of incident tsunami waves when interacting with coastal infrastructures is analysed on the basis of numerical simulations of near-shore tsunami waves' propagation. Tsunami impact at the affected site is assessed through computing inundation and current velocity using a high-resolution digital terrain model that incorporates bathymetric, topographic and coastal structures data. Results, in terms of near-shore tsunami propagation snapshots, waves' interaction with coastal barriers, and spatial distributions of flow depths and speeds, are presented and discussed in light of what was observed during the 2011 Tohoku-oki tsunami. Predicted results show different levels of impact that different tsunami wave conditions could generate in the region. Existing coastal barriers around the El Jadida harbour succeeded in reflecting relatively small waves generated by some scenarios, but failed in preventing the overtopping caused by waves from others. Considering the scenario highly impacting the El Jadida coast, significant inundations are computed at the sandy beach and unprotected areas. The modelled dramatic tsunami impact in the region shows the need for additional tsunami standards not only for sea-defense structures but also for the coastal dwellings and houses to provide potential in-place evacuation.

  12. National Geophysical Data Center Tsunami Data Archive

    Science.gov (United States)

    Stroker, K. J.; Dunbar, P. K.; Brocko, R.

    2008-12-01

    NOAA's National Geophysical Data Center (NGDC) and co-located World Data Center for Geophysics and Marine Geology long-term tsunami data archive provides data and derived products essential for tsunami hazard assessment, forecast and warning, inundation modeling, preparedness, mitigation, education, and research. As a result of NOAA's efforts to strengthen its tsunami activities, the long-term tsunami data archive has grown from less than 5 gigabyte in 2004 to more than 2 terabytes in 2008. The types of data archived for tsunami research and operation activities have also expanded in fulfillment of the P.L. 109-424. The archive now consists of: global historical tsunami, significant earthquake and significant volcanic eruptions database; global tsunami deposits and proxies database; reference database; damage photos; coastal water-level data (i.e. digital tide gauge data and marigrams on microfiche); bottom pressure recorder (BPR) data as collected by Deep-ocean Assessment and Reporting of Tsunamis (DART) buoys. The tsunami data archive comes from a wide variety of data providers and sources. These include the NOAA Tsunami Warning Centers, NOAA National Data Buoy Center, NOAA National Ocean Service, IOC/NOAA International Tsunami Information Center, NOAA Pacific Marine Environmental Laboratory, U.S. Geological Survey, tsunami catalogs, reconnaissance reports, journal articles, newspaper articles, internet web pages, and email. NGDC has been active in the management of some of these data for more than 50 years while other data management efforts are more recent. These data are openly available, either directly on-line or by contacting NGDC. All of the NGDC tsunami and related databases are stored in a relational database management system. These data are accessible over the Web as tables, reports, and interactive maps. The maps provide integrated web-based GIS access to individual GIS layers including tsunami sources, tsunami effects, significant earthquakes

  13. Safety goals for seismic and tsunami risks: Lessons learned from the Fukushima Daiichi disaster

    Energy Technology Data Exchange (ETDEWEB)

    Saji, Genn, E-mail: sajig@bd5.so-net.ne.jp

    2014-12-15

    Highlights: • Reviewed why the Fukushima disaster was not anticipated among seismologists. • Reviewed Fukushima Daiichi's preparedness against the earthquake and tsunami. • There was a large “cliff edge” in radiological consequences from the design basis tsunami. • By including earthquakes as an “external event” resulted in insufficient “defense in depths”. • Proposes a new probabilistic seismic and tsunami safety goal be developed. - Abstract: This paper first reviews why the potential occurrence of the Tohoku-oki earthquake with momentum magnitude M{sub w} of 9.0 earthquake was not anticipated by Japanese seismologists, and to clarify our limitations in predicting rare but severe earthquakes at our current knowledge in the field of geosciences. Although there was a large volume of historical records related to earthquakes and tsunamis, generally this data infer high plate coupling in regions where earthquakes were known to have already occurred, with only partial or even no coupling from the Japan Trench to a point approximately midway between the trench and the coastline—precisely the region where the 2011 Tohoku-Oki earthquake occurred. This phenomenon has been explained as a “silent earthquake” or a fault creep as observed at the San Andreas Faults in the US. Considering the large uncertainties in seismic events, nuclear power plants should be conservatively designed with adequate safety margins. TEPCO's preparedness against seismic and tsunami hazards were reviewed in order to clarify why the established safety margin was not sufficient during the Fukushima Daiichi. It was found that the plant incorporated the necessary safety margins against seismic oscillation however, there was a large “cliff edge” in which the radiological consequences surged by several orders of magnitude from the design basis tsunami. Since the tsunami's height was greater than the ground level of the turbine hall, a large amount of the

  14. Safety goals for seismic and tsunami risks: Lessons learned from the Fukushima Daiichi disaster

    International Nuclear Information System (INIS)

    Saji, Genn

    2014-01-01

    Highlights: • Reviewed why the Fukushima disaster was not anticipated among seismologists. • Reviewed Fukushima Daiichi's preparedness against the earthquake and tsunami. • There was a large “cliff edge” in radiological consequences from the design basis tsunami. • By including earthquakes as an “external event” resulted in insufficient “defense in depths”. • Proposes a new probabilistic seismic and tsunami safety goal be developed. - Abstract: This paper first reviews why the potential occurrence of the Tohoku-oki earthquake with momentum magnitude M w of 9.0 earthquake was not anticipated by Japanese seismologists, and to clarify our limitations in predicting rare but severe earthquakes at our current knowledge in the field of geosciences. Although there was a large volume of historical records related to earthquakes and tsunamis, generally this data infer high plate coupling in regions where earthquakes were known to have already occurred, with only partial or even no coupling from the Japan Trench to a point approximately midway between the trench and the coastline—precisely the region where the 2011 Tohoku-Oki earthquake occurred. This phenomenon has been explained as a “silent earthquake” or a fault creep as observed at the San Andreas Faults in the US. Considering the large uncertainties in seismic events, nuclear power plants should be conservatively designed with adequate safety margins. TEPCO's preparedness against seismic and tsunami hazards were reviewed in order to clarify why the established safety margin was not sufficient during the Fukushima Daiichi. It was found that the plant incorporated the necessary safety margins against seismic oscillation however, there was a large “cliff edge” in which the radiological consequences surged by several orders of magnitude from the design basis tsunami. Since the tsunami's height was greater than the ground level of the turbine hall, a large amount of the tsunami

  15. Correlation of Fault Size, Moment Magnitude, and Tsunami Height to Proved Paleo-tsunami Data in Sulawesi Indonesia

    Science.gov (United States)

    Julius, A. M.; Pribadi, S.

    2016-02-01

    Sulawesi (Indonesia) island is located in the meeting of three large plates i.e. Indo-Australia, Pacific, and Eurasia. This configuration surely make high risk on tsunami by earthquake and by sea floor landslide. NOAA and Russia Tsunami Laboratory show more than 20 tsunami data recorded in Sulawesi since 1820. Based on this data, determine of correlation between all tsunami parameter need to be done to proved all event in the past. Complete data of magnitudes, fault sizes and tsunami heights in this study sourced from NOAA and Russia Tsunami database and completed with Pacific Tsunami Warning Center (PTWC) catalog. This study aims to find correlation between fault area, moment magnitude, and tsunami height by simple regression in Sulawesi. The step of this research are data collect, processing, and regression analysis. Result shows very good correlation, each moment magnitude, tsunami heights, and fault parameter i.e. long, wide, and slip are correlate linier. In increasing of fault area, the tsunami height and moment magnitude value also increase. In increasing of moment magnitude, tsunami height also increase. This analysis is enough to proved all Sulawesi tsunami parameter catalog in NOAA, Russia Tsunami Laboratory and PTWC are correct. Keyword: tsunami, magnitude, height, fault

  16. Evaluation and Numerical Simulation of Tsunami for Coastal Nuclear Power Plants of India

    International Nuclear Information System (INIS)

    Sharma, Pavan K.; Singh, R.K.; Ghosh, A.K.; Kushwaha, H.S.

    2006-01-01

    Recent tsunami generated on December 26, 2004 due to Sumatra earthquake of magnitude 9.3 resulted in inundation at the various coastal sites of India. The site selection and design of Indian nuclear power plants demand the evaluation of run up and the structural barriers for the coastal plants: Besides it is also desirable to evaluate the early warning system for tsunami-genic earthquakes. The tsunamis originate from submarine faults, underwater volcanic activities, sub-aerial landslides impinging on the sea and submarine landslides. In case of a submarine earthquake-induced tsunami the wave is generated in the fluid domain due to displacement of the seabed. There are three phases of tsunami: generation, propagation, and run-up. Reactor Safety Division (RSD) of Bhabha Atomic Research Centre (BARC), Trombay has initiated computational simulation for all the three phases of tsunami source generation, its propagation and finally run up evaluation for the protection of public life, property and various industrial infrastructures located on the coastal regions of India. These studies could be effectively utilized for design and implementation of early warning system for coastal region of the country apart from catering to the needs of Indian nuclear installations. This paper presents some results of tsunami waves based on different analytical/numerical approaches with shallow water wave theory. (authors)

  17. Tsunami deposits in the Balearic Islands (western Mediterranean) and implications for hazard assessment.

    Science.gov (United States)

    Paris, Raphael; Wassmer, Patrick; Roger, Jean; Loevenbruck, Anne

    2010-05-01

    Significant earthquakes occur along the north Algerian and Carboneras faults (e.g. Djijelli 1865, Zemmouri 2003) and they may generate tsunamis in the western Mediterranean Basin and Alboran Sea, where tsunami hazard are poorly documented. The coast of southern Spain and Balearic Islands are densely populated, with touristic areas and important harbors. The 2003 event generated a small tsunami in the Balearic Islands (ships were moved by oscillations during more than 2 hours in some harbors). Reicherter et al. (2009) found evidences of two past tsunamis in lagoon of the Cabo de Gata (near Almeria), which they ascribed to the 1522 earthquake and an earlier event (islands revealed few evidences of past tsunamis. Thin sandy layers with marine bioclasts, possibly deposited by tsunamis, were found in three areas at altitudes always lower than 2m. Boulder clusters were found along the southern coast of Mallorca, but they could have been deposited by storms as well. These investigations are realized in the framework of the MAREMOTI project, funded by the French ANR and leaded by the CEA - DASE. Reicherter, K., Becker-Heidmann, P., 2009. Tsunami deposits in the western Mediterranean: remains of the 1522 Almeria earthquake? Geological Society Special Publications, London, 316, 217-235.

  18. Study of characteristic of tsunami base on the coastal morphology in north Donggala, Central Sulawesi

    Science.gov (United States)

    Rahmadaningsi, W. S. N.; Assegaf, A. H.; Setyonegoro, W.; Paharuddin

    2018-03-01

    The northern arm of Sulawesi potentials to generate earthquake and Tsunami due to the existence of subduction zone in sulawesi sea. It makes the North Donggala as an area with active seismicity. One of the earthquake and Tsunami events occurred is the earthquake and tsunami of Toli-Toli 1996 (M 7.9) causing 9 people are killed and severe damage in Tonggolobibi, Siboang, and Balukang. This earthquake induced tsunami runup of 3.4 m and inundated as far as 400 meters. The aims of this study is to predict runup and inundation area using numerical model and to find out the characteristics of Tsunami wave on straight, bay and cape shape coastal morphology and slopes of coastal. The data in this research consist of are the Etopo2 bathymetry data in data obtained from NOAA (National Oceanic and Atmospheric Administration), Toli-toli’s main earthquakes focal mechanism data 1st January1996 from GCMT (Global Centroid Moment Tensor), the data gained from the SRTM (Shuttle Radar Topography Mission) data 30 m and land cover data in 1996 from Ministry of environment and forestry . Single fault model is used to predict the high of tsunami run-up and to inundation area along Donggala coastal area. Its reviewed by morphology of coastal area that higher run up shows occurs at coastline type like bay have higher run up compare to area with cape and straight coastline. The result shows that the slopes have negative or contras correlation with Tsunami runup and its inundation area.

  19. Outreach to the Public on Earthquake and Tsunami Safety with Limited Human Resources: Train the Trainers Pilot Program in Puerto Rico

    Science.gov (United States)

    Gonzalez Ruiz, W.; Vanacore, E. A.; Gomez, G.; Martinez Colon, J. F.; Perez, F.; Baez-Sanchez, G.; Flores Hots, V. E.; Lopez, A. M.; Huerfano, V.; Figueroa, J. M.

    2017-12-01

    Given the limited human resources available to interact directly with the public and disseminate information on earthquake and tsunami safety, the Puerto Rico Seismic Network has developed the Train the Trainers course, designed exclusively for emergency management officers (EMOs). This three-day training course provides a complete package of educational tools that will allow EMOs to present standard conferences, and lectures, with the appropriate and accurate information for different audiences on earthquake and tsunami hazard and safety. Here we present preliminary observations and lessons learned from the pilot program that was offered in July 2017 to 20 EMOs from the twelve Puerto Rico Emergency Management Agency (PREMA) zones and two students from the University of Puerto Rico Mayaguez. To ensure sufficient preparation, the training course provided evaluation tools including written and practical exams that participants were required to score 80% or more to complete the training successfully. Of the 20 EMO participants, 18 EMOs passed the final exam. Preliminary analysis of the pre-test scores and the post-test scores, show a score improvement between 8% to 46% amongst the participants. These 18 participants will receive a certificate as well as tools and resources to offer earthquakes and tsunamis conferences for up to two years across Puerto Rico and its outlying islands. To ensure that the pilot participants will provide conferences to the public PRSN required a signed commitment to give at least 5 conferences in one year from each participant and PRSN will monitor the participants for the next two years to evaluate the efficacy of the program. However, based on the preliminary data this program appears to be an effective method to increase the amount of outreach professionals on the Island.

  20. ASSESSMENT OF THE TSUNAMIGENIC POTENTIAL ALONG THE NORTHERN CARIBBEAN MARGIN Case Study: Earthquake and Tsunamis of 12 January 2010 in Haiti.

    Directory of Open Access Journals (Sweden)

    George Pararas-Carayannis

    2010-01-01

    Full Text Available The potential tsunami risk for Hispaniola, as well as for the other Greater Antilles Islands is assessed by reviewing the complex geotectonic processes and regimes along the Northern Caribbean margin, including the convergent, compressional and collisional tectonic activity of subduction, transition, shearing, lateral movements, accretion and crustal deformation caused by the eastward movement of the Caribbean plate in relation to the North American plate. These complex tectonic interactions have created a broad, diffuse tectonic boundary that has resulted in an extensive, internal deformational sliver slab - the Gonâve microplate – as well as further segmentation into two other microplates with similarly diffused boundary characteristics where tsunamigenic earthquakes have and will again occur. The Gonâve microplate is the most prominent along the Northern Caribbean margin and extends from the Cayman Spreading Center to Mona Pass, between Puerto Rico and the island of Hispaniola, where the 1918 destructive tsunami was generated. The northern boundary of this sliver microplate is defined by the Oriente strike-slip fault south of Cuba, which appears to be an extension of the fault system traversing the northern part of Hispaniola, while the southern boundary is defined by another major strike-slip fault zone where the Haiti earthquake of 12 January 2010 occurred. Potentially tsunamigenic regions along the Northern Caribbean margin are located not only along the boundaries of the Gonâve microplate’s dominant western transform zone but particularly within the eastern tectonic regimes of the margin where subduction is dominant - particularly along the Puerto Rico trench. The Haiti earthquake of 12 January 2010 and its focal mechanism are examined, as they provide additional clues of potential tsunami generation that can occur along transform zones and, more specifically, from interplate and intraplate seismic events and subsequently induced

  1. Preliminary study on tsunami vulnerability assessment in south coast of Korean Peninsula

    International Nuclear Information System (INIS)

    Min, Byung Il; Suh, Kyung Suk; Lee, Gyumin; Jun, Kyoung Soo

    2015-01-01

    The potential impact on the coast by the Nankai trough earthquake has been reviewed in 2003 by the Japanese government. However, the magnitude-9.0 earthquake that occurred in March 2011, the Japanese government has decided to re-evaluation the event and extensive studies revealed that the occurrence of a magnitude-9.0 earthquake in the Nankai Trough. In this revealed result, the tsunami waves have been estimated approximately 50% bigger than previous results. A simulation of the tsunami that would be caused by an earthquake in the Nankai Trough was conducted to determine the effect on the Korean coast. The tsunami waves are simulated to propagate southeastward, diffract clockwise south of Kyushu and head for Cheju Island and the southern coast of Korea. The detailed coastal structures are not included in this research because the computational cost. Further simulation studies are underway to take into account coastal structure

  2. Preliminary study on tsunami vulnerability assessment in south coast of Korean Peninsula

    Energy Technology Data Exchange (ETDEWEB)

    Min, Byung Il; Suh, Kyung Suk [Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of); Lee, Gyumin; Jun, Kyoung Soo [Sungkyunkwan University, Suwon (Korea, Republic of)

    2015-05-15

    The potential impact on the coast by the Nankai trough earthquake has been reviewed in 2003 by the Japanese government. However, the magnitude-9.0 earthquake that occurred in March 2011, the Japanese government has decided to re-evaluation the event and extensive studies revealed that the occurrence of a magnitude-9.0 earthquake in the Nankai Trough. In this revealed result, the tsunami waves have been estimated approximately 50% bigger than previous results. A simulation of the tsunami that would be caused by an earthquake in the Nankai Trough was conducted to determine the effect on the Korean coast. The tsunami waves are simulated to propagate southeastward, diffract clockwise south of Kyushu and head for Cheju Island and the southern coast of Korea. The detailed coastal structures are not included in this research because the computational cost. Further simulation studies are underway to take into account coastal structure.

  3. Checking of seismic and tsunami hazard for coastal NPP of Chinese continent after Fukushima nuclear accident

    Institute of Scientific and Technical Information of China (English)

    Chang Xiangdong; Zhou Bengang; Zhao Lianda

    2013-01-01

    A checking on seismic and tsunami hazard for coastal nuclear power plant (NPP) of Chinese continent has been made after Japanese Fukushima nuclear accident caused by earthquake tsunami.The results of the checking are introduced briefly in this paper,including the evaluations of seismic and tsunami hazard in NPP siting period,checking results on seismic and tsunami hazard.Because Chinese coastal area belongs to the continental shelf and far from the boundary of plate collision,the tsunami hazard is not significant for coastal area of Chinese continent.However,the effect from tsunami still can' t be excluded absolutely since calculated result of Manila trench tsunami source although the tsunami wave is lower than water level from storm surge.The research about earthquake tsunami will continue in future.The tsunami warning system and emergency program of NPP will be established based on principle of defense in depth in China.

  4. Economic impacts of the SAFRR tsunami scenario in California: Chapter H in The SAFRR (Science Application for Risk Reduction) Tsunami Scenario

    Science.gov (United States)

    Wein, Anne; Rose, Adam; Sue Wing, Ian; Wei, Dan

    2013-01-01

    This study evaluates the hypothetical economic impacts of the SAFRR (Science Application for Risk Reduction) tsunami scenario to the California economy. The SAFRR scenario simulates a tsunami generated by a hypothetical magnitude 9.1 earthquake that occurs offshore of the Alaska Peninsula (Kirby and others, 2013). Economic impacts are measured by the estimated reduction in California’s gross domestic product (GDP), the standard economic measure of the total value of goods and services produced. Economic impacts are derived from the physical damages from the tsunami as described by Porter and others (2013). The principal physical damages that result in disruption of the California economy are (1) about $100 million in damages to the twin Ports of Los Angeles (POLA) and Long Beach (POLB), (2) about $700 million in damages to marinas, and (3) about $2.5 billion in damages to buildings and contents (properties) in the tsunami inundation zone on the California coast. The study of economic impacts does not include the impacts from damages to roads, bridges, railroads, and agricultural production or fires in fuel storage facilities because these damages will be minimal with respect to the California economy. The economic impacts of damage to other California ports are not included in this study because detailed evaluation of the physical damage to these ports was not available in time for this report. The analysis of economic impacts is accomplished in several steps. First, estimates are made for the direct economic impacts that result in immediate business interruption losses in individual sectors of the economy due to physical damage to facilities or to disruption of the flow of production units (commodities necessary for production). Second, the total economic impacts (consisting of both direct and indirect effects) are measured by including the general equilibrium (essentially quantity and price multiplier effects) of lost production in other sectors by ripple

  5. Scientific aspects of the Tohoku earthquake and Fukushima nuclear accident

    Science.gov (United States)

    Koketsu, Kazuki

    2016-04-01

    We investigated the 2011 Tohoku earthquake, the accident of the Fukushima Daiichi nuclear power plant, and assessments conducted beforehand for earthquake and tsunami potential in the Pacific offshore region of the Tohoku District. The results of our investigation show that all the assessments failed to foresee the earthquake and its related tsunami, which was the main cause of the accident. Therefore, the disaster caused by the earthquake, and the accident were scientifically unforeseeable at the time. However, for a zone neighboring the reactors, a 2008 assessment showed tsunamis higher than the plant height. As a lesson learned from the accident, companies operating nuclear power plants should be prepared using even such assessment results for neighboring zones.

  6. Preliminary numerical simulations of the 27 February 2010 Chile tsunami: first results and hints in a tsunami early warning perspective

    Science.gov (United States)

    Tinti, S.; Tonini, R.; Armigliato, A.; Zaniboni, F.; Pagnoni, G.; Gallazzi, Sara; Bressan, Lidia

    2010-05-01

    The tsunamigenic earthquake (M 8.8) that occurred offshore central Chile on 27 February 2010 can be classified as a typical subduction-zone earthquake. The effects of the ensuing tsunami have been devastating along the Chile coasts, and especially between the cities of Valparaiso and Talcahuano, and in the Juan Fernandez islands. The tsunami propagated across the entire Pacific Ocean, hitting with variable intensity almost all the coasts facing the basin. While the far-field propagation was quite well tracked almost in real-time by the warning centres and reasonably well reproduced by the forecast models, the toll of lives and the severity of the damage caused by the tsunami in the near-field occurred with no local alert nor warning and sadly confirms that the protection of the communities placed close to the tsunami sources is still an unresolved problem in the tsunami early warning field. The purpose of this study is two-fold. On one side we perform numerical simulations of the tsunami starting from different earthquake models which we built on the basis of the preliminary seismic parameters (location, magnitude and focal mechanism) made available by the seismological agencies immediately after the event, or retrieved from more detailed and refined studies published online in the following days and weeks. The comparison with the available records of both offshore DART buoys and coastal tide-gauges is used to put some preliminary constraints on the best-fitting fault model. The numerical simulations are performed by means of the finite-difference code UBO-TSUFD, developed and maintained by the Tsunami Research Team of the University of Bologna, Italy, which can solve both the linear and non-linear versions of the shallow-water equations on nested grids. The second purpose of this study is to use the conclusions drawn in the previous part in a tsunami early warning perspective. In the framework of the EU-funded project DEWS (Distant Early Warning System), we will

  7. Tsunami hazard assessment along Diba-Oman and Diba-Al-Emirates coasts

    Directory of Open Access Journals (Sweden)

    El-Hussain Issa

    2017-01-01

    Full Text Available Tsunami is among the most devastating natural hazards phenomenon responsible for significant loss of life and property throughout history. The Sultanate of Oman and United Arab Emirates are among the Indian Ocean countries that were subjected to one confirmed tsunami in November 27, 1945 due to an Mw 8.1 earthquake in Makran Subduction Zone. In this study, we present preliminary deterministic tsunami hazard assessment for the coasts of Diba Oman and Diba Al-Emirates, which are located on the western coast of the Oman Sea. The tsunami vulnerability of these cities increases due to the construction of many critical infrastructures and urban concentration along their coasts. Therefore, tsunami hazard assessment is necessary to mitigate the risk on the socio-economic system and sustainable developments. The major known source of tsunamis able to impact both coasts of Oman and United Arab Emirates is the Makran Subduction Zone (MSZ which extends for approximately 900 km. The deterministic approach uses specific scenarios considering the maximum credible earthquakes occurring in the MSZ and computes the ensuing tsunami impact in the coasts of the study area. The maximum wave height graphs and inundation maps are obtained for tsunami scenarios caused by 8.8 earthquake magnitude in eastern MSZ and 8.2 magnitude from western MSZ. The Mw8.8 eastern MSZ causes a maximum inundation distance of 447 meters and a maximum flow depth of 1.37 meter. Maximum inundation distance larger than 420 meters occurs due to the Mw8.2 western MSZ scenario. For this scenario, numerical simulations show a maximum flow depth of about 2.34 meters.

  8. Deterministic Tectonic Origin Tsunami Hazard Analysis for the Eastern Mediterranean and its Connected Seas

    Science.gov (United States)

    Necmioglu, O.; Meral Ozel, N.

    2014-12-01

    Accurate earthquake source parameters are essential for any tsunami hazard assessment and mitigation, including early warning systems. Complex tectonic setting makes the a priori accurate assumptions of earthquake source parameters difficult and characterization of the faulting type is a challenge. Information on tsunamigenic sources is of crucial importance in the Eastern Mediterranean and its Connected Seas, especially considering the short arrival times and lack of offshore sea-level measurements. In addition, the scientific community have had to abandon the paradigm of a ''maximum earthquake'' predictable from simple tectonic parameters (Ruff and Kanamori, 1980) in the wake of the 2004 Sumatra event (Okal, 2010) and one of the lessons learnt from the 2011 Tohoku event was that tsunami hazard maps may need to be prepared for infrequent gigantic earthquakes as well as more frequent smaller-sized earthquakes (Satake, 2011). We have initiated an extensive modeling study to perform a deterministic Tsunami Hazard Analysis for the Eastern Mediterranean and its Connected Seas. Characteristic earthquake source parameters (strike, dip, rake, depth, Mwmax) at each 0.5° x 0.5° size bin for 0-40 km depth (total of 310 bins) and for 40-100 km depth (total of 92 bins) in the Eastern Mediterranean, Aegean and Black Sea region (30°N-48°N and 22°E-44°E) have been assigned from the harmonization of the available databases and previous studies. These parameters have been used as input parameters for the deterministic tsunami hazard modeling. Nested Tsunami simulations of 6h duration with a coarse (2 arc-min) and medium (1 arc-min) grid resolution have been simulated at EC-JRC premises for Black Sea and Eastern and Central Mediterranean (30°N-41.5°N and 8°E-37°E) for each source defined using shallow water finite-difference SWAN code (Mader, 2004) for the magnitude range of 6.5 - Mwmax defined for that bin with a Mw increment of 0.1. Results show that not only the

  9. The Amorgos, Greece earthquake and tsunami of 09 July 1956: Focal mechanism and field survey

    Science.gov (United States)

    Okal, E. A.; Synolakis, C. E.; Yalciner, A. C.

    2004-12-01

    The earthquake of 09 July 1956 near the Greek island of Amorgos (M sub PAS = 7.8) is the largest event of the past 75 years in the Aegean. It created the most damaging tsunami to hit Greece in the past century, with reported run-up of 25 m on the Eastern coast of Amorgos. This prompted Ambraseys [1960] to propose that underwater landslides may have occurred. We use the PDFM method introduced by Reymond and Okal [2000] to invert a moment tensor from a limited set of spectral amplitudes of mantle waves. Our solution features a normal faulting mechanism (phi = 245 deg; delta = 67 deg; lambda = 281 deg.) and a moment of 3.9 * 10**27 dyn-cm. In parallel, we have started a systematic survey of tsunami run-up heights in the Aegean Islands and the Asia Minor coast of Turkey, through the interview of elderly witnesses of the tsunami. Our growing dataset presently includes 29 data points on seven islands and at eight villages on the Turkish Coast. We confirm a single run-up value of 20 m on Eastern Amorgos, with measured run-up limited to 8 m on Astypalea and at most 3 m at other locations (1 m on the Turkish coast). The uniqueness of the large run-up value, in the proximity of locales with milder values, does suggest that it could be due to the influence of a localized underwater landslide.

  10. NOAA/WEST COAST AND ALASKA TSUNAMI WARNING CENTER PACIFIC OCEAN RESPONSE CRITERIA

    Directory of Open Access Journals (Sweden)

    Garry Rogers

    2008-01-01

    Full Text Available New West Coast/Alaska Tsunami Warning Center (WCATWC response criteria for earthquakes occurring in the Pacific basin are presented. Initial warning decisions are based on earthquake location, magnitude, depth, and - dependent on magnitude - either distance from source or pre- computed threat estimates generated from tsunami models. The new criteria will help limit the geographical extent of warnings and advisories to threatened regions, and complement the new operational tsunami product suite.Changes to the previous criteria include: adding hypocentral depth dependence, reducing geographical warning extent for the lower magnitude ranges, setting special criteria for areas not well-connected to the open ocean, basing warning extent on pre-computed threat levels versus tsunami travel time for very large events, including the new advisory product, using the advisory product for far-offshore events in the lower magnitude ranges, and specifying distances from the coast for on-shore events which may be tsunamigenic.This report sets a baseline for response criteria used by the WCATWC considering its processing and observational data capabilities as well as its organizational requirements. Criteria are set for tsunamis generated by earthquakes, which are by far the main cause of tsunami generation (either directly through sea floor displacement or indirectly by triggering of slumps. As further research and development provides better tsunami source definition, observational data streams, and improved analysis tools, the criteria will continue to adjust. Future lines of research and development capable of providing operational tsunami warning centers with better tools are discussed.

  11. The tsunami phenomenon

    Science.gov (United States)

    Röbke, B. R.; Vött, A.

    2017-12-01

    With human activity increasingly concentrating on coasts, tsunamis (from Japanese tsu = harbour, nami = wave) are a major natural hazard to today's society. Stimulated by disastrous tsunami impacts in recent years, for instance in south-east Asia (2004) or in Japan (2011), tsunami science has significantly flourished, which has brought great advances in hazard assessment and mitigation plans. Based on tsunami research of the last decades, this paper provides a thorough treatise on the tsunami phenomenon from a geoscientific point of view. Starting with the wave features, tsunamis are introduced as long shallow water waves or wave trains crossing entire oceans without major energy loss. At the coast, tsunamis typically show wave shoaling, funnelling and resonance effects as well as a significant run-up and backflow. Tsunami waves are caused by a sudden displacement of the water column due to a number of various trigger mechanisms. Such are earthquakes as the main trigger, submarine and subaerial mass wastings, volcanic activity, atmospheric disturbances (meteotsunamis) and cosmic impacts, as is demonstrated by giving corresponding examples from the past. Tsunamis are known to have a significant sedimentary and geomorphological off- and onshore response. So-called tsunamites form allochthonous high-energy deposits that are left at the coast during tsunami landfall. Tsunami deposits show typical sedimentary features, as basal erosional unconformities, fining-upward and -landward, a high content of marine fossils, rip-up clasts from underlying units and mud caps, all reflecting the hydrodynamic processes during inundation. The on- and offshore behaviour of tsunamis and related sedimentary processes can be simulated using hydro- and morphodynamic numerical models. The paper provides an overview of the basic tsunami modelling techniques, including discretisation, guidelines for appropriate temporal and spatial resolution as well as the nesting method. Furthermore, the

  12. Tsunamigenic earthquake simulations using experimentally derived friction laws

    Science.gov (United States)

    Murphy, S.; Di Toro, G.; Romano, F.; Scala, A.; Lorito, S.; Spagnuolo, E.; Aretusini, S.; Festa, G.; Piatanesi, A.; Nielsen, S.

    2018-03-01

    Seismological, tsunami and geodetic observations have shown that subduction zones are complex systems where the properties of earthquake rupture vary with depth as a result of different pre-stress and frictional conditions. A wealth of earthquakes of different sizes and different source features (e.g. rupture duration) can be generated in subduction zones, including tsunami earthquakes, some of which can produce extreme tsunamigenic events. Here, we offer a geological perspective principally accounting for depth-dependent frictional conditions, while adopting a simplified distribution of on-fault tectonic pre-stress. We combine a lithology-controlled, depth-dependent experimental friction law with 2D elastodynamic rupture simulations for a Tohoku-like subduction zone cross-section. Subduction zone fault rocks are dominantly incohesive and clay-rich near the surface, transitioning to cohesive and more crystalline at depth. By randomly shifting along fault dip the location of the high shear stress regions ("asperities"), moderate to great thrust earthquakes and tsunami earthquakes are produced that are quite consistent with seismological, geodetic, and tsunami observations. As an effect of depth-dependent friction in our model, slip is confined to the high stress asperity at depth; near the surface rupture is impeded by the rock-clay transition constraining slip to the clay-rich layer. However, when the high stress asperity is located in the clay-to-crystalline rock transition, great thrust earthquakes can be generated similar to the Mw 9 Tohoku (2011) earthquake.

  13. EARLY DETECTION OF NEAR-FIELD TSUNAMIS USING UNDERWATER SENSOR NETWORKS

    Directory of Open Access Journals (Sweden)

    L. E. Freitag

    2012-01-01

    Full Text Available We propose a novel approach for near-field tsunami detection, specifically for the area near the city of Padang, Indonesia. Padang is located on the western shore of Sumatra, directly across from the Mentawai segment of the Sunda Trench, where accumulated strain has not been released since the great earthquake of 1797. Consequently, the risk of a major tsunamigenic earthquake on this segment is high. Currently, no ocean-bottom pressure sensors are deployed in the Mentawai basin to provide a definitive tsunami warning for Padang. Timely warnings are essential to initiate evacuation procedures and minimize loss of human life. Our approach augments existing technology with a network of underwater sensors to detect tsunamis generated by an earthquake or landslide fast enough to provide at least 15 minutes of warning. Data from the underwater sensor network would feed into existing decision support systems that accept input from land and sea-based sensors and provide warning information to city and regional authorities.

  14. Landslide tsunami hazard in the Indonesian Sunda Arc

    Directory of Open Access Journals (Sweden)

    S. Brune

    2010-03-01

    Full Text Available The Indonesian archipelago is known for the occurrence of catastrophic earthquake-generated tsunamis along the Sunda Arc. The tsunami hazard associated with submarine landslides however has not been fully addressed. In this paper, we compile the known tsunamigenic events where landslide involvement is certain and summarize the properties of published landslides that were identified with geophysical methods. We depict novel mass movements, found in newly available bathymetry, and determine their key parameters. Using numerical modeling, we compute possible tsunami scenarios. Furthermore, we propose a way of identifying landslide tsunamis using an array of few buoys with bottom pressure units.

  15. The First Real-Time Tsunami Animation

    Science.gov (United States)

    Becker, N. C.; Wang, D.; McCreery, C.; Weinstein, S.; Ward, B.

    2014-12-01

    For the first time a U.S. tsunami warning center created and issued a tsunami forecast model animation while the tsunami was still crossing an ocean. Pacific Tsunami Warning Center (PTWC) scientists had predicted they would have this ability (Becker et al., 2012) with their RIFT forecast model (Wang et al., 2009) by using rapidly-determined W-phase centroid-moment tensor earthquake focal mechanisms as tsunami sources in the RIFT model (Wang et al., 2012). PTWC then acquired its own YouTube channel in 2013 for its outreach efforts that showed animations of historic tsunamis (Becker et al., 2013), but could also be a platform for sharing future tsunami animations. The 8.2 Mw earthquake of 1 April 2014 prompted PTWC to issue official warnings for a dangerous tsunami in Chile, Peru and Ecuador. PTWC ended these warnings five hours later, then issued its new tsunami marine hazard product (i.e., no coastal evacuations) for the State of Hawaii. With the international warning canceled but with a domestic hazard still present PTWC generated a forecast model animation and uploaded it to its YouTube channel six hours before the arrival of the first waves in Hawaii. PTWC also gave copies of this animation to television reporters who in turn passed it on to their national broadcast networks. PTWC then created a version for NOAA's Science on a Sphere system so it could be shown on these exhibits as the tsunami was still crossing the Pacific Ocean. While it is difficult to determine how many people saw this animation since local, national, and international news networks showed it in their broadcasts, PTWC's YouTube channel provides some statistics. As of 1 August 2014 this animation has garnered more than 650,000 views. Previous animations, typically released during significant anniversaries, rarely get more than 10,000 views, and even then only when external websites share them. Clearly there is a high demand for a tsunami graphic that shows both the speed and the severity of a

  16. To enhance effectiveness of response to emergency situations following earthquakes, tsunamis, and nuclear disasters

    International Nuclear Information System (INIS)

    Shimada, Jiro; Tase, Choichiro; Tsukada, Yasuhiko; Hasegawa, Arifumi; Ikegami, Yukihiro; Iida, Hiroshi

    2013-01-01

    From the immediate aftermath of the 2011 Tohoku earthquake and tsunami and the ensuing Fukushima Daiichi nuclear disaster. Fukushima Medical University Hospital urgently needed to operate as both a core disaster hospital and a secondary radiation emergency hospital. The disaster drills and emergency simulation training that had been undertaken to prepare for such a scenario proved to be immensely helpful. However, due to the fact that the disaster caused much more damage than expected putting that preparation perfectly into practice was impossible. In any disaster, it is important to collect human intelligence. Therefore, simulating the collection of human intelligence is necessary in order to supplement drills and training and improve rapid response following a disaster. (author)

  17. Interviewing insights regarding the fatalities inflicted by the 2011 Great East Japan Earthquake

    Science.gov (United States)

    Ando, M.; Ishida, M.; Hayashi, Y.; Mizuki, C.; Nishikawa, Y.; Tu, Y.

    2013-09-01

    One hundred fifty survivors of the 11 March 2011 Great East Japan Earthquake (Tohoku-oki earthquake) (Mw = 9.0) were interviewed to study the causes of deaths from the associated tsunami in coastal areas of Tohoku. The first official tsunami warning underestimated the height of the tsunami and 40% of the interviewees did not obtain this warning due to immediate blackouts and a lack of communication after the earthquake. Many chose to remain in dangerous locations based on the underestimated warning and their experiences with previous smaller tsunamis and/or due to misunderstanding the mitigating effects of nearby breakwaters in blocking incoming tsunamis. Some delayed their evacuation to perform family safety checks, and in many situations, the people affected misunderstood the risks involved in tsunamis. In this area, three large tsunamis have struck in the 115 yr preceding the 2011 tsunami. These tsunamis remained in the collective memory of communities, and numerous measures against future tsunami damage, such as breakwaters and tsunami evacuation drills, had been implemented. Despite these preparedness efforts, approximately 18 500 deaths and cases of missing persons occurred. The death rate with the age of 65 and above was particularly high, four times higher than that with other age groups. These interviews indicate that deaths resulted from a variety of reasons, but if residents had taken immediate action after the major ground motion stopped, most residents might have been saved. Education about the science behind earthquakes and tsunamis could help save more lives in the future.

  18. Discrimination of tsunamigenic earthquakes by ionospheric sounding using GNSS observations of total electron content from the Sumatran GPS Array

    Science.gov (United States)

    Manta, F.; Feng, L.; Occhipinti, G.; Taisne, B.; Hill, E.

    2017-12-01

    Tsunami earthquakes generate tsunamis larger than expected for their seismic magnitude. They rupture the shallow megathrust, which is usually at significant distance from land-based monitoring networks. This distance presents a challenge in accurately estimating the magnitude and source extent of tsunami earthquakes. Whether these parameters can be estimated reliably is critical to the success of tsunami early warning systems. In this work, we investigate the potential role of using GNSS-observed ionospheric total electron content (TEC) to discriminate tsunami earthquakes, by introducing for the first time the TEC Intensity Index (TECII) for rapidly identify tsunamigenic earthquakes. We examine two Mw 7.8 megathrust events along the Sumatran subduction zone with data from the Sumatran GPS Array (SuGAr). Both events triggered a tsunami alert that was canceled later. The Banyaks event (April 6th, 2010) did not generate a tsunami and caused only minor earthquake-related damage to infrastructure. On the contrary, the Mentawai event (October 25th, 2010) produced a large tsunami with run-up heights of >16 m along the southwestern coasts of the Pagai Islands. The tsunami claimed more than 400 lives. The primary difference between the two events was the depth of rupture: the Mentawai event ruptured a very shallow (earthquake (TECII = 1.14) and a characteristic signature of a tsunami 40 minutes after the event. These two signals reveal the large surface displacement at the rupture, and the consequent destructive tsunami. This comparative study of two earthquakes with the same magnitude at different depths highlights the potential role of ionospheric monitoring by GNSS to tsunami early warning systems

  19. Source characteristics of the Nicaraguan tsunami earthquake of September 2, 1992

    Science.gov (United States)

    Ide, Satoshi; Imamura, Fumihiko; Yoshida, Yasuhiro; Abe, Katsuyuki

    1993-05-01

    The source mechanisms of the Nicaraguan tsunami earthquake of September 2, 1992 is studied via waveforms of body waves and surface waves recorded on global broadband seismographs. The possibility of a single force is ruled out from radiation patterns and the amplitude ratio of Rayleigh and Love waves. The main shock is interpreted as low-angle thrust fault with strike of 302 deg, dip of 16 deg, and slip of 87 deg, the Cocos plate underthrusting beneath the Caribbean plate. The seismic moment from surface wave analysis is 3.0 x 10 exp 20 Nm. The source dimension is estimated to be 200 x 100 km from the aftershock area. The inversion results of body waves suggest bilateral rupture with rupture velocity as low as 1.5 km/s and duration time of about 100 s. The source process time is unusually long, from which it is inferred that the associated crustal deformation has a long time constant.

  20. The elusive AD 1826 tsunami, South Westland, New Zealand

    International Nuclear Information System (INIS)

    Goff, J.R.; Wells, A.; Chague-Goff, C.; Nichol, S.L.; Devoy, R.J.N.

    2004-01-01

    In AD 1826 sealers reported earthquake and tsunami activity in Fiordland, although contemporary or near-contemporary accounts of tsunami inundation at the time are elusive. A detailed analysis of recent sediments fom Okarito Lagoon builds on contextual evidence provided by earlier research concerning past tsunami inundation. Sedimentological, geochemical, micropalaeontological and geochronological data are used to determine palaeoenvironments before, during and after what was most probably tsunami inundation in AD 1826. The most compelling chronological control is provided by a young cohort of trees growing on a raised shoreline bench stranded by a drop in the lagoon water level following tsunami inundation. (author). 42 refs., 9 figs., 1 tab

  1. A tsunami wave propagation analysis for the Ulchin Nuclear Power Plant considering the tsunami sources of western part of Japan

    International Nuclear Information System (INIS)

    Rhee, Hyun Me; Kim, Min Kyu; Sheen, Dong Hoon; Choi, In Kil

    2013-01-01

    The accident which was caused by a tsunami and the Great East-Japan earthquake in 2011 occurred at the Fukushima Nuclear Power Plant (NPP) site. It is obvious that the NPP accident could be incurred by the tsunami. Therefore a Probabilistic Tsunami Hazard Analysis (PTHA) for an NPP site should be required in Korea. The PTHA methodology is developed on the PSHA (Probabilistic Seismic Hazard Analysis) method which is performed by using various tsunami sources and their weights. In this study, the fault sources of northwestern part of Japan were used to analyze as the tsunami sources. These fault sources were suggested by the Atomic Energy Society of Japan (AESJ). To perform the PTHA, the calculations of maximum and minimum wave elevations from the result of tsunami simulations are required. Thus, in this study, tsunami wave propagation analysis were performed for developing the future study of the PTHA

  2. Real-time Tsunami Inundation Prediction Using High Performance Computers

    Science.gov (United States)

    Oishi, Y.; Imamura, F.; Sugawara, D.

    2014-12-01

    Recently off-shore tsunami observation stations based on cabled ocean bottom pressure gauges are actively being deployed especially in Japan. These cabled systems are designed to provide real-time tsunami data before tsunamis reach coastlines for disaster mitigation purposes. To receive real benefits of these observations, real-time analysis techniques to make an effective use of these data are necessary. A representative study was made by Tsushima et al. (2009) that proposed a method to provide instant tsunami source prediction based on achieving tsunami waveform data. As time passes, the prediction is improved by using updated waveform data. After a tsunami source is predicted, tsunami waveforms are synthesized from pre-computed tsunami Green functions of linear long wave equations. Tsushima et al. (2014) updated the method by combining the tsunami waveform inversion with an instant inversion of coseismic crustal deformation and improved the prediction accuracy and speed in the early stages. For disaster mitigation purposes, real-time predictions of tsunami inundation are also important. In this study, we discuss the possibility of real-time tsunami inundation predictions, which require faster-than-real-time tsunami inundation simulation in addition to instant tsunami source analysis. Although the computational amount is large to solve non-linear shallow water equations for inundation predictions, it has become executable through the recent developments of high performance computing technologies. We conducted parallel computations of tsunami inundation and achieved 6.0 TFLOPS by using 19,000 CPU cores. We employed a leap-frog finite difference method with nested staggered grids of which resolution range from 405 m to 5 m. The resolution ratio of each nested domain was 1/3. Total number of grid points were 13 million, and the time step was 0.1 seconds. Tsunami sources of 2011 Tohoku-oki earthquake were tested. The inundation prediction up to 2 hours after the

  3. PEMETAAN BAHAYA GEMPA BUMI DAN POTENSI TSU-NAMI DI BALI BERDASARKAN NILAI SEISMISITAS

    OpenAIRE

    Bayu Baskara; I Ketut Sukarasa; Ardhianto Septiadhi

    2017-01-01

    Bali is one of the areas prone to earthquake and tsunami as being at the junction of two plates, namely the Eurasian plate and the Indo-Australian plate is located in the south of Bali and back arc trust zones are located in the North of Bali. We need research on the potential dangers of earthquakes and tsunami in Bali are based on the value of seismicity which is interpreted by the value of b and a. This study uses earthquake data on the coordinates 6?-11? SLand 114?-116? EL with 339 data th...

  4. Mental health and related factors after the Great East Japan earthquake and tsunami.

    Directory of Open Access Journals (Sweden)

    Yukari Yokoyama

    Full Text Available Mental health is one of the most important issues facing disaster survivors. The purpose of this study is to determine the prevalence and correlates of mental health problems in survivors of the Great East Japan Earthquake and Tsunami at 6-11 months after the disaster. The questionnaire and notification were sent to the survivors in three municipalities in the Tohoku area of the Northern part of Honshu, Japan's largest island, between September 2011 and February 2012. Questionnaires were sent to 12,772, 11,411, and 18,648 residents in the Yamada, Otsuchi, and Rikuzentakata municipalities, respectively. Residents were asked to bring the completed questionnaires to their health check-ups. A total of 11,124 or (26.0% of them underwent health check-ups, and 10,198 were enrolled. We excluded 179 for whom a K6 score was missing and two who were both 17 years of age, which left 10,025 study participants (3,934 male and 6,091 female, mean age 61.0 years. K6 was used to measure mental health problems. The respondents were classified into moderate (5-12 of K6 and serious mental health problems (13+. A total of 42.6% of the respondents had moderate or serious mental health problems. Multivariate analysis showed that women were significantly associated with mental health problems. Other variables associated with mental health problems were: younger male, health complaints, severe economic status, relocations, and lack of a social network. An interaction effect of sex and economic status on severe mental health problems was statistically significant. Our findings suggest that mental health problems were prevalent in survivors of the Great East Japan Earthquake and Tsunami. For men and women, health complaints, severe economic status, relocations, and lack of social network may be important risk factors of poor mental health. For men, interventions focusing on economic support may be particularly useful in reducing mental health problems after the disaster.

  5. Issues of tsunami hazard maps revealed by the 2011 Tohoku tsunami

    Science.gov (United States)

    Sugimoto, M.

    2013-12-01

    Tsunami scientists are imposed responsibilities of selection for people's tsunami evacuation place after the 2011 Tohoku Tsunami in Japan. A lot of matured people died out of tsunami hazard zone based on tsunami hazard map though students made a miracle by evacuation on their own judgment in Kamaishi city. Tsunami hazard maps were based on numerical model smaller than actual magnitude 9. How can we bridge the gap between hazard map and future disasters? We have to discuss about using tsunami numerical model better enough to contribute tsunami hazard map. How do we have to improve tsunami hazard map? Tsunami hazard map should be revised included possibility of upthrust or downthrust after earthquakes and social information. Ground sank 1.14m below sea level in Ayukawa town, Tohoku. Ministry of Land, Infrastructure, Transport and Tourism's research shows around 10% people know about tsunami hazard map in Japan. However, people know about their evacuation places (buildings) through experienced drills once a year even though most people did not know about tsunami hazard map. We need wider spread of tsunami hazard with contingency of science (See the botom disaster handbook material's URL). California Emergency Management Agency (CEMA) team practically shows one good practice and solution to me. I followed their field trip in Catalina Island, California in Sep 2011. A team members are multidisciplinary specialists: A geologist, a GIS specialist, oceanographers in USC (tsunami numerical modeler) and a private company, a local policeman, a disaster manager, a local authority and so on. They check field based on their own specialties. They conduct an on-the-spot inspection of ambiguous locations between tsunami numerical model and real field conditions today. The data always become older. They pay attention not only to topographical conditions but also to social conditions: vulnerable people, elementary schools and so on. It takes a long time to check such field

  6. Tsunami recurrence in the eastern Alaska-Aleutian arc: A Holocene stratigraphic record from Chirikof Island, Alaska

    Science.gov (United States)

    Nelson, Alan R.; Briggs, Richard; Dura, Tina; Engelhart, Simon E.; Gelfenbaum, Guy; Bradley, Lee-Ann; Forman, S.L.; Vane, Christopher H.; Kelley, K.A.

    2015-01-01

    Despite the role of the Alaska-Aleutian megathrust as the source of some of the largest earthquakes and tsunamis, the history of its pre–twentieth century tsunamis is largely unknown west of the rupture zone of the great (magnitude, M 9.2) 1964 earthquake. Stratigraphy in core transects at two boggy lowland sites on Chirikof Island’s southwest coast preserves tsunami deposits dating from the postglacial to the twentieth century. In a 500-m-long basin 13–15 m above sea level and 400 m from the sea, 4 of 10 sandy to silty beds in a 3–5-m-thick sequence of freshwater peat were probably deposited by tsunamis. The freshwater peat sequence beneath a gently sloping alluvial fan 2 km to the east, 5–15 m above sea level and 550 m from the sea, contains 20 sandy to silty beds deposited since 3.5 ka; at least 13 were probably deposited by tsunamis. Although most of the sandy beds have consistent thicknesses (over distances of 10–265 m), sharp lower contacts, good sorting, and/or upward fining typical of tsunami deposits, the beds contain abundant freshwater diatoms, very few brackish-water diatoms, and no marine diatoms. Apparently, tsunamis traveling inland over low dunes and boggy lowland entrained largely freshwater diatoms. Abundant fragmented diatoms, and lake species in some sandy beds not found in host peat, were probably transported by tsunamis to elevations of >10 m at the eastern site. Single-aliquot regeneration optically stimulated luminescence dating of the third youngest bed is consistent with its having been deposited by the tsunami recorded at Russian hunting outposts in 1788, and with the second youngest bed being deposited by a tsunami during an upper plate earthquake in 1880. We infer from stratigraphy, 14C-dated peat deposition rates, and unpublished analyses of the island’s history that the 1938 tsunami may locally have reached an elevation of >10 m. As this is the first record of Aleutian tsunamis extending throughout the Holocene, we

  7. Assessment of the tsunami hazard on Moroccan coasts using numerical modeling

    Directory of Open Access Journals (Sweden)

    Amine Meriem

    2018-01-01

    This work can be considered as a first approach to the study and understanding tsunamis. Although Morocco has known since historical times, earthquakes and tsunamis along its coasts. This preliminary study is mainly intended to show the contribution of the numerical simulation of tsunamis, with a concrete application of the 1755 Tsunami of Lisbon based on the four source zones involving the five potentially tsunamigenic faults that are generally mentioned in the literature for this major event.

  8. Real-time earthquake source imaging: An offline test for the 2011 Tohoku earthquake

    Science.gov (United States)

    Zhang, Yong; Wang, Rongjiang; Zschau, Jochen; Parolai, Stefano; Dahm, Torsten

    2014-05-01

    In recent decades, great efforts have been expended in real-time seismology aiming at earthquake and tsunami early warning. One of the most important issues is the real-time assessment of earthquake rupture processes using near-field seismogeodetic networks. Currently, earthquake early warning systems are mostly based on the rapid estimate of P-wave magnitude, which contains generally large uncertainties and the known saturation problem. In the case of the 2011 Mw9.0 Tohoku earthquake, JMA (Japan Meteorological Agency) released the first warning of the event with M7.2 after 25 s. The following updates of the magnitude even decreased to M6.3-6.6. Finally, the magnitude estimate stabilized at M8.1 after about two minutes. This led consequently to the underestimated tsunami heights. By using the newly developed Iterative Deconvolution and Stacking (IDS) method for automatic source imaging, we demonstrate an offline test for the real-time analysis of the strong-motion and GPS seismograms of the 2011 Tohoku earthquake. The results show that we had been theoretically able to image the complex rupture process of the 2011 Tohoku earthquake automatically soon after or even during the rupture process. In general, what had happened on the fault could be robustly imaged with a time delay of about 30 s by using either the strong-motion (KiK-net) or the GPS (GEONET) real-time data. This implies that the new real-time source imaging technique is helpful to reduce false and missing warnings, and therefore should play an important role in future tsunami early warning and earthquake rapid response systems.

  9. Tsunami generation and associated waves in the water column and seabed due to an asymmetric earthquake motion within an anisotropic substratum

    Science.gov (United States)

    Bagheri, Amirhossein; Greenhalgh, Stewart; Khojasteh, Ali; Rahimian, Mohammad; Attarnejad, Reza

    2016-10-01

    In this paper, closed-form integral expressions are derived to describe how surface gravity waves (tsunamis) are generated when general asymmetric ground displacement (due to earthquake rupturing), involving both horizontal and vertical components of motion, occurs at arbitrary depth within the interior of an anisotropic subsea solid beneath the ocean. In addition, we compute the resultant hydrodynamic pressure within the seawater and the elastic wavefield within the seabed at any position. The method of potential functions and an integral transform approach, accompanied by a special contour integration scheme, are adopted to handle the equations of motion and produce the numerical results. The formulation accounts for any number of possible acoustic-gravity modes and is valid for both shallow and deep water situations as well as for any focal depth of the earthquake source. Phase and group velocity dispersion curves are developed for surface gravity (tsunami mode), acoustic-gravity, Rayleigh, and Scholte waves. Several asymptotic cases which arise from the general analysis are discussed and compared to existing solutions. The role of effective parameters such as hypocenter location and frequency of excitation is examined and illustrated through several figures which show the propagation pattern in the vertical and horizontal directions. Attention is directed to the unexpected contribution from the horizontal ground motion. The results have important application in several fields such as tsunami hazard prediction, marine seismology, and offshore and coastal engineering. In a companion paper, we examine the effect of ocean stratification on the appearance and character of internal and surface gravity waves.

  10. Public Perceptions of Tsunamis and the NOAA TsunamiReady Program in Los Angeles

    Science.gov (United States)

    Rosati, A.

    2010-12-01

    After the devastating December 2004 Indian Ocean Tsunami, California and other coastal states began installing "Tsunami Warning Zone" and "Evacuation Route" signs at beaches and major access roads. The geography of the Los Angeles area may not be conducive to signage alone for communication of the tsunami risk and safety precautions. Over a year after installation, most people surveyed did not know about or recognize the tsunami signs. More alarming is that many did not believe a tsunami could occur in the area even though earthquake generated waves have reached nearby beaches as recently as September 2009! UPDATE: FEB. 2010. Fifty two percent of the 147 people surveyed did not believe they would survive a natural disaster in Los Angeles. Given the unique geography of Los Angeles, how can the city and county improve the mental health of its citizens before and after a natural disaster? This poster begins to address the issues of community self-efficacy and resiliency in the face of tsunamis. Of note for future research, the data from this survey showed that most people believed climate change would increase the occurrence of tsunamis. Also, the public understanding of water inundation was disturbingly low. As scientists, it is important to understand the big picture of our research - how it is ultimately communicated, understood, and used by the public.

  11. Prototype Tsunami Evacuation Park in Padang, West Sumatra, Indonesia

    Science.gov (United States)

    Tucker, B. E.; Cedillos, V.; Deierlein, G.; Di Mauro, M.; Kornberg, K.

    2012-12-01

    Padang, Indonesia, a city of some 900,000 people, half of whom live close to the coast and within a five-meter elevation above sea level, has one of the highest tsunami risks in the world due to its close offshore thrust-fault seismic hazard, flat terrain and dense population. There is a high probability that a tsunami will strike the shores of Padang, flooding half of the area of the city, within the next 30 years. If that tsunami occurred today, it is estimated that several hundred thousand people would die, as they could not reach safe ground in the ~30 minute interval between the earthquake's occurrence and the tsunami's arrival. Padang's needs have been amply demonstrated: after earthquakes in 2007, 2009, 2011 and 2012, citizens, thinking that those earthquakes might cause a tsunami, tried to evacuate in cars and motorbikes, which created traffic jams, and most could not reach safe ground in 30 minutes. Since 2008, GeoHazards International (GHI) and Stanford University have studied a range of options for improving this situation, including ways to accelerate evacuation to high ground with pedestrian bridges and widened roads, and means of "vertical" evacuation in multi-story buildings, mosques, pedestrian overpasses, and Tsunami Evacuation Parks (TEPs), which are man-made hills with recreation facilities on top. TEPs proved most practical and cost-effective for Padang, given the available budget, technology and time. The Earth Observatory Singapore (EOS) developed an agent-based model that simulates pedestrian and vehicular evacuation to assess tsunami risk and risk reduction interventions in Southeast Asia. EOS applied this model to analyze the effectiveness in Padang of TEPs over other tsunami risk management approaches in terms of evacuation times and the number of people saved. The model shows that only ~24,000 people (20% of the total population) in the northern part of Padang can reach safe ground within 30 minutes, if people evacuate using cars and

  12. An Evaluation of Infrastructure for Tsunami Evacuation in Padang, West Sumatra, Indonesia (Invited)

    Science.gov (United States)

    Cedillos, V.; Canney, N.; Deierlein, G.; Diposaptono, S.; Geist, E. L.; Henderson, S.; Ismail, F.; Jachowski, N.; McAdoo, B. G.; Muhari, A.; Natawidjaja, D. H.; Sieh, K. E.; Toth, J.; Tucker, B. E.; Wood, K.

    2009-12-01

    Padang has one of the world’s highest tsunami risks due to its high hazard, vulnerable terrain and population density. The current strategy to prepare for tsunamis in Padang is focused on developing early warning systems, planning evacuation routes, conducting evacuation drills, and raising local awareness. Although these are all necessary, they are insufficient. Padang’s proximity to the Sunda Trench and flat terrain make reaching safe ground impossible for much of the population. The natural warning in Padang - a strong earthquake that lasts over a minute - will be the first indicator of a potential tsunami. People will have about 30 minutes after the earthquake to reach safe ground. It is estimated that roughly 50,000 people in Padang will be unable to evacuate in that time. Given these conditions, other means to prepare for the expected tsunami must be developed. With this motivation, GeoHazards International and Stanford University’s Chapter of Engineers for a Sustainable World partnered with Indonesian organizations - Andalas University and Tsunami Alert Community in Padang, Laboratory for Earth Hazards, and the Ministry of Marine Affairs and Fisheries - in an effort to evaluate the need for and feasibility of tsunami evacuation infrastructure in Padang. Tsunami evacuation infrastructure can include earthquake-resistant bridges and evacuation structures that rise above the maximum tsunami water level, and can withstand the expected earthquake and tsunami forces. The choices for evacuation structures vary widely - new and existing buildings, evacuation towers, soil berms, elevated highways and pedestrian overpasses. This interdisciplinary project conducted a course at Stanford University, undertook several field investigations, and concluded that: (1) tsunami evacuation structures and bridges are essential to protect the people in Padang, (2) there is a need for a more thorough engineering-based evaluation than conducted to-date of the suitability of

  13. Evaluation of the impact of 1983 east sea tsunami at the site of Ulchin nuclear power plant

    International Nuclear Information System (INIS)

    Lee, H. K.; Lee, D. S.; Choi, S. H.

    2001-01-01

    In the past, we carried out the safety assessment study at the site of Ulchin NPP against tsunamis on the basis of maximum earthquake magnitude 7 3/4 and available tsunamigenic earthquake fault parameters. But, recently, based on the seismic gap theory some geologists and seismologists warned that the earthquakes with larger magnitude than was expected might occur in the East Sea region. And, the need of re-evaluation of safety is suggested. In this study, to investigate the applicability of a finite difference model, we simulated the 1983 East Sea Tsunami at the Imwon Harbor where the maximum run-up height of tsunami was observed. The general agreement was obtained in the viewpoint of maxium wave run-up height. Finally, we evaluated the rise and drop of sea water level at the site of Ulchin NPP and concluded that the site of Ulchin NPP is safe against tsunami of the same magnitude of 1983 East Sea Tsunami

  14. The seismic project of the National Tsunami Hazard Mitigation Program

    Science.gov (United States)

    Oppenheimer, D.H.; Bittenbinder, A.N.; Bogaert, B.M.; Buland, R.P.; Dietz, L.D.; Hansen, R.A.; Malone, S.D.; McCreery, C.S.; Sokolowski, T.J.; Whitmore, P.M.; Weaver, C.S.

    2005-01-01

    In 1997, the Federal Emergency Management Agency (FEMA), National Oceanic and Atmospheric Administration (NOAA), U.S. Geological Survey (USGS), and the five western States of Alaska, California, Hawaii, Oregon, and Washington joined in a partnership called the National Tsunami Hazard Mitigation Program (NTHMP) to enhance the quality and quantity of seismic data provided to the NOAA tsunami warning centers in Alaska and Hawaii. The NTHMP funded a seismic project that now provides the warning centers with real-time seismic data over dedicated communication links and the Internet from regional seismic networks monitoring earthquakes in the five western states, the U.S. National Seismic Network in Colorado, and from domestic and global seismic stations operated by other agencies. The goal of the project is to reduce the time needed to issue a tsunami warning by providing the warning centers with high-dynamic range, broadband waveforms in near real time. An additional goal is to reduce the likelihood of issuing false tsunami warnings by rapidly providing to the warning centers parametric information on earthquakes that could indicate their tsunamigenic potential, such as hypocenters, magnitudes, moment tensors, and shake distribution maps. New or upgraded field instrumentation was installed over a 5-year period at 53 seismic stations in the five western states. Data from these instruments has been integrated into the seismic network utilizing Earthworm software. This network has significantly reduced the time needed to respond to teleseismic and regional earthquakes. Notably, the West Coast/Alaska Tsunami Warning Center responded to the 28 February 2001 Mw 6.8 Nisqually earthquake beneath Olympia, Washington within 2 minutes compared to an average response time of over 10 minutes for the previous 18 years. ?? Springer 2005.

  15. Tsunami Early Warning via a Physics-Based Simulation Pipeline

    Science.gov (United States)

    Wilson, J. M.; Rundle, J. B.; Donnellan, A.; Ward, S. N.; Komjathy, A.

    2017-12-01

    Through independent efforts, physics-based simulations of earthquakes, tsunamis, and atmospheric signatures of these phenomenon have been developed. With the goal of producing tsunami forecasts and early warning tools for at-risk regions, we join these three spheres to create a simulation pipeline. The Virtual Quake simulator can produce thousands of years of synthetic seismicity on large, complex fault geometries, as well as the expected surface displacement in tsunamigenic regions. These displacements are used as initial conditions for tsunami simulators, such as Tsunami Squares, to produce catalogs of potential tsunami scenarios with probabilities. Finally, these tsunami scenarios can act as input for simulations of associated ionospheric total electron content, signals which can be detected by GNSS satellites for purposes of early warning in the event of a real tsunami. We present the most recent developments in this project.

  16. Seismic and tsunami hazard in Puerto Rico and the Virgin Islands

    Science.gov (United States)

    Dillon, William P.; Frankel, Arthur D.; Mueller, Charles S.; Rodriguez, Rafael W.; ten Brink, Uri S.

    1999-01-01

    Executive SummaryPuerto Rico and the Virgin Islands are located at an active plate boundary between the North American plate and the northeast corner of the Caribbean plate. The region was subject in historical times to large magnitude earthquakes and devastating tsunamis. A major downward tilt of the sea floor north of Puerto Rico and the Virgin Islands, large submarine rockslides, and an unusually large negative gravity anomaly are also indicative of a tectonically active region. Scientists have so far failed to explain the deformation of this region in a coherent and predictable picture, such as in California, and this has hampered their ability to assess seismic and tsunami hazards in the region. The NE corner of the Caribbean is unique among the seismically-active regions of the United States in that it is mostly covered by water. This fact presents an additional challenge for seismic and tsunami hazard assessment and mitigation.The workshop, convened in San Juan on March 23-24, 1999, was "historic" in that it brought together for the first time a broad spectrum of scientists, engineers, and public and private sector officials who deal with such diverse questions as tectonic models, probabilistic assessment of seismic hazard, prediction of tsunami runup, strong ground motion, building codes, stability of man-made structures, and the public’s preparedness for natural disasters. It was an opportunity for all the participants to find out how their own activity fit into the broad picture of science and how it aids society in hazard assessment and mitigation. In addition, the workshop was offered as a continuing education course at the Colegio de Ingenieros y Agrimensores de Puerto Rico, which assured a rapid dissemination of the results to the local community. A news conference which took place during the workshop alerted the public to the efforts of the USGS, other Federal agencies, the Commonwealth of Puerto Rico, universities and the private sector.During the

  17. Tsunami hazard maps of spanish coast at national scale from seismic sources

    Science.gov (United States)

    Aniel-Quiroga, Íñigo; González, Mauricio; Álvarez-Gómez, José Antonio; García, Pablo

    2017-04-01

    Tsunamis are a moderately frequent phenomenon in the NEAM (North East Atlantic and Mediterranean) region, and consequently in Spain, as historic and recent events have affected this area. I.e., the 1755 earthquake and tsunami affected the Spanish Atlantic coasts of Huelva and Cadiz and the 2003 Boumerdés earthquake triggered a tsunami that reached Balearic island coast in less than 45 minutes. The risk in Spain is real and, its population and tourism rate makes it vulnerable to this kind of catastrophic events. The Indian Ocean tsunami in 2004 and the tsunami in Japan in 2011 launched the worldwide development and application of tsunami risk reduction measures that have been taken as a priority in this field. On November 20th 2015 the directive of the Spanish civil protection agency on planning under the emergency of tsunami was presented. As part of the Spanish National Security strategy, this document specifies the structure of the action plans at different levels: National, regional and local. In this sense, the first step is the proper evaluation of the tsunami hazard at National scale. This work deals with the assessment of the tsunami hazard in Spain, by means of numerical simulations, focused on the elaboration of tsunami hazard maps at National scale. To get this, following a deterministic approach, the seismic structures whose earthquakes could generate the worst tsunamis affecting the coast of Spain have been compiled and characterized. These worst sources have been propagated numerically along a reconstructed bathymetry, built from the best resolution available data. This high-resolution bathymetry was joined with a 25-m resolution DTM, to generate continuous offshore-onshore space, allowing the calculation of the flooded areas prompted by each selected source. The numerical model applied for the calculation of the tsunami propagations was COMCOT. The maps resulting from the numerical simulations show not only the tsunami amplitude at coastal areas but

  18. Summary of Great East Japan Earthquake response at Onagawa Nuclear Power Station and further safety improvement measures

    International Nuclear Information System (INIS)

    Sato, Toru

    2013-01-01

    A large earthquake occurred on March 11, 2011 and tsunami was generated following it. The East Japan suffered serious damage by the earthquake and tsunami. This is called the Great East Japan Earthquake. Onagawa Nuclear Power Station (NPS) is located closest to the epicenter of Great East Japan Earthquake. We experienced intense shake by the earthquake and some flooding from the tsunami, however, we have succeeded safely cold shutdown of the reactors. In this paper, we introduce summary of Great East Japan Earthquake response a Onagawa NPS and safety improvement measures which are based on both experience of Onagawa NPS and lesson from Fukushima Daiichi NPS accident. (author)

  19. Variations in population vulnerability to tectonic and landslide-related tsunami hazards in Alaska

    Science.gov (United States)

    Wood, Nathan J.; Peters, Jeff

    2015-01-01

    Effective tsunami risk reduction requires an understanding of how at-risk populations are specifically vulnerable to tsunami threats. Vulnerability assessments primarily have been based on single hazard zones, even though a coastal community may be threatened by multiple tsunami sources that vary locally in terms of inundation extents and wave arrival times. We use the Alaskan coastal communities of Cordova, Kodiak, Seward, Valdez, and Whittier (USA), as a case study to explore population vulnerability to multiple tsunami threats. We use anisotropic pedestrian evacuation models to assess variations in population exposure as a function of travel time out of hazard zones associated with tectonic and landslide-related tsunamis (based on scenarios similar to the 1964 M w9.2 Good Friday earthquake and tsunami disaster). Results demonstrate that there are thousands of residents, employees, and business customers in tsunami hazard zones associated with tectonically generated waves, but that at-risk individuals will likely have sufficient time to evacuate to high ground before waves are estimated to arrive 30–60 min after generation. Tsunami hazard zones associated with submarine landslides initiated by a subduction zone earthquake are smaller and contain fewer people, but many at-risk individuals may not have enough time to evacuate as waves are estimated to arrive in 1–2 min and evacuations may need to occur during earthquake ground shaking. For all hazard zones, employees and customers at businesses far outnumber residents at their homes and evacuation travel times are highest on docks and along waterfronts. Results suggest that population vulnerability studies related to tsunami hazards should recognize non-residential populations and differences in wave arrival times if emergency managers are to develop realistic preparedness and outreach efforts.

  20. Tsunami Prediction and Earthquake Parameters Estimation in the Red Sea

    KAUST Repository

    Sawlan, Zaid A

    2012-01-01

    parameters and topography. This thesis introduces a real-time tsunami forecasting method that combines tsunami model with observations using a hybrid ensemble Kalman filter and ensemble Kalman smoother. The filter is used for state prediction while

  1. Ocean-bottom pressure changes above a fault area for tsunami excitation and propagation observed by a submarine dense network

    Science.gov (United States)

    Yomogida, K.; Saito, T.

    2017-12-01

    Conventional tsunami excitation and propagation have been formulated by incompressible fluid with velocity components. This approach is valid in most cases because we usually analyze tunamis as "long gravity waves" excited by submarine earthquakes. Newly developed ocean-bottom tsunami networks such as S-net and DONET have dramatically changed the above situation for the following two reasons: (1) tsunami propagations are now directly observed in a 2-D array manner without being suffered by complex "site effects" of sea shore, and (2) initial tsunami features can be directly detected just above a fault area. Removing the incompressibility assumption of sea water, we have formulated a new representation of tsunami excitation based on not velocity but displacement components. As a result, not only dynamics but static term (i.e., the component of zero frequency) can be naturally introduced, which is important for the pressure observed on the ocean floor, which ocean-bottom tsunami stations are going to record. The acceleration on the ocean floor should be combined with the conventional tsunami height (that is, the deformation of the sea level above a given station) in the measurement of ocean-bottom pressure although the acceleration exists only during fault motions in time. The M7.2 Off Fukushima earthquake on 22 November 2016 was the first event that excited large tsunamis within the territory of S-net stations. The propagation of tsunamis is found to be highly non-uniform, because of the strong velocity (i.e., sea depth) gradient perpendicular to the axis of Japan Trench. The earthquake was located in a shallow sea close to the coast, so that all the tsunami energy is reflected by the trench region of high velocity. Tsunami records (pressure gauges) within its fault area recorded clear slow motions of tsunamis (i.e., sea level changes) but also large high-frequency signals, as predicted by our theoretical result. That is, it may be difficult to extract tsunami

  2. Brief communication "Seismic and acoustic-gravity signals from the source of the 2004 Indian Ocean Tsunami"

    Directory of Open Access Journals (Sweden)

    A. Raveloson

    2012-02-01

    Full Text Available The great Sumatra-Andaman earthquake of 26 December 2004 caused seismic waves propagating through the solid Earth, tsunami waves propagating through the ocean and infrasound or acoustic-gravity waves propagating through the atmosphere. Since the infrasound wave travels faster than its associated tsunami, it is for warning purposes very intriguing to study the possibility of infrasound generation directly at the earthquake source. Garces et al. (2005 and Le Pichon et al. (2005 emphasized that infrasound was generated by mountainous islands near the epicenter and by tsunami propagation along the continental shelf to the Bay of Bengal. Mikumo et al. (2008 concluded from the analysis of travel times and amplitudes of first arriving acoustic-gravity waves with periods of about 400–700 s that these waves are caused by coseismic motion of the sea surface mainly to the west of the Nicobar islands in the open seas. We reanalyzed the acoustic-gravity waves and corrected the first arrival times of Mikumo et al. (2008 by up to 20 min. We found the source of the first arriving acoustic-gravity wave about 300 km to the north of the US Geological Survey earthquake epicenter. This confirms the result of Mikumo et al. (2008 that sea level changes at the earthquake source cause long period acoustic-gravity waves, which indicate that a tsunami was generated. Therefore, a denser local network of infrasound stations may be helpful for tsunami warnings, not only for very large earthquakes.

  3. Development of a decision support system for tsunami evacuation: application to the Jiyang District of Sanya city in China

    Science.gov (United States)

    Hou, Jingming; Yuan, Ye; Wang, Peitao; Ren, Zhiyuan; Li, Xiaojuan

    2017-03-01

    Major tsunami disasters often cause great damage in the first few hours following an earthquake. The possible severity of such events requires preparations to prevent tsunami disasters or mitigate them. This paper is an attempt to develop a decision support system for rapid tsunami evacuation for local decision makers. Based on the numerical results database of tsunami disasters, this system can quickly obtain the tsunami inundation and travel time. Because numerical models are calculated in advance, this system can reduce decision-making time. Population distribution, as a vulnerability factor, was analyzed to identify areas of high risk for tsunami disasters. Combined with spatial data, this system can comprehensively analyze the dynamic and static evacuation process and identify problems that negatively impact evacuation, thus supporting the decision-making for tsunami evacuation in high-risk areas. When an earthquake and tsunami occur, this system can rapidly obtain the tsunami inundation and travel time and provide information to assist with tsunami evacuation operations.

  4. A NEW TSUNAMI RISK SCALE FOR WARNING SYSTEMS - APPLICATION TO THE BAY OF ALGIERS IN ALGERIA, WEST MEDITERRANEAN SEA

    Directory of Open Access Journals (Sweden)

    L. A. Amir

    2013-01-01

    Full Text Available The city of Algiers and the surrounding coastal areas in northern Algeria are vulnerable to earthquakes which range from moderate to severe. In 2006, using several possible earthquake scenarios for the Western Mediterranean, the Japan International Cooperation Agency and the Algerian National Seismic Engineering Research Center predicted that heavy damage could occur in the Algiers region. Algerian Civil Defense authorities are particularly concerned by the threat of near-field earthquakes, associated slides and rock falls, as well as for tsunamis that can be generated. The present study proposes a new tsunami risk scale that provides information about the exposed communities and infrastructure, which can be used for regional tsunami alerts and warnings. Furthermore, it evaluates the vulnerability along the Bay of Algiers from tsunamigenic earthquakes. The JMA seismic intensity scale (Shindo scale and the corresponding seismic peak ground accelerations are used in the evaluation. The results of tsunami modeling studies and of earthquake vulnerability assessment described by the present study, emphasize the significance of public education and preparedness in efforts to mitigate loss of life and damage to property.

  5. The 2006 July 17 Java (Indonesia) tsunami from satellite imagery and numerical modelling: a single or complex source?

    Science.gov (United States)

    Hébert, H.; Burg, P.-E.; Binet, R.; Lavigne, F.; Allgeyer, S.; Schindelé, F.

    2012-12-01

    The Mw 7.8 2006 July 17 earthquake off the southern coast of Java, Indonesia, has been responsible for a very large tsunami causing more than 700 casualties. The tsunami has been observed on at least 200 km of coastline in the region of Pangandaran (West Java), with run-up heights from 5 to more than 20 m. Such a large tsunami, with respect to the source magnitude, has been attributed to the slow character of the seismic rupture, defining the event as a so-called tsunami earthquake, but it has also been suggested that the largest run-up heights are actually the result of a second local landslide source. Here we test whether a single slow earthquake source can explain the tsunami run-up, using a combination of new detailed data in the region of the largest run-ups and comparison with modelled run-ups for a range of plausible earthquake source models. Using high-resolution satellite imagery (SPOT 5 and Quickbird), the coastal impact of the tsunami is refined in the surroundings of the high-security Permisan prison on Nusa Kambangan island, where 20 m run-up had been recorded directly after the event. These data confirm the extreme inundation lengths close to the prison, and extend the area of maximum impact further along the Nusa Kambangan island (about 20 km of shoreline), where inundation lengths reach several hundreds of metres, suggesting run-up as high as 10-15 m. Tsunami modelling has been conducted in detail for the high run-up Permisan area (Nusa Kambangan) and the PLTU power plant about 25 km eastwards, where run-up reached only 4-6 m and a video recording of the tsunami arrival is available. For the Permisan prison a high-resolution DEM was built from stereoscopic satellite imagery. The regular basin of the PLTU plant was designed using photographs and direct observations. For the earthquake's mechanism, both static (infinite) and finite (kinematic) ruptures are investigated using two published source models. The models account rather well for the sea level

  6. Building strategies for tsunami scenarios databases to be used in a tsunami early warning decision support system: an application to western Iberia

    Science.gov (United States)

    Tinti, S.; Armigliato, A.; Pagnoni, G.; Zaniboni, F.

    2012-04-01

    One of the most challenging goals that the geo-scientific community is facing after the catastrophic tsunami occurred on December 2004 in the Indian Ocean is to develop the so-called "next generation" Tsunami Early Warning Systems (TEWS). Indeed, the meaning of "next generation" does not refer to the aim of a TEWS, which obviously remains to detect whether a tsunami has been generated or not by a given source and, in the first case, to send proper warnings and/or alerts in a suitable time to all the countries and communities that can be affected by the tsunami. Instead, "next generation" identifies with the development of a Decision Support System (DSS) that, in general terms, relies on 1) an integrated set of seismic, geodetic and marine sensors whose objective is to detect and characterise the possible tsunamigenic sources and to monitor instrumentally the time and space evolution of the generated tsunami, 2) databases of pre-computed numerical tsunami scenarios to be suitably combined based on the information coming from the sensor environment and to be used to forecast the degree of exposition of different coastal places both in the near- and in the far-field, 3) a proper overall (software) system architecture. The EU-FP7 TRIDEC Project aims at developing such a DSS and has selected two test areas in the Euro-Mediterranean region, namely the western Iberian margin and the eastern Mediterranean (Turkish coasts). In this study, we discuss the strategies that are being adopted in TRIDEC to build the databases of pre-computed tsunami scenarios and we show some applications to the western Iberian margin. In particular, two different databases are being populated, called "Virtual Scenario Database" (VSDB) and "Matching Scenario Database" (MSDB). The VSDB contains detailed simulations of few selected earthquake-generated tsunamis. The cases provided by the members of the VSDB are computed "real events"; in other words, they represent the unknowns that the TRIDEC

  7. Characterization of tsunamigenic earthquake in Java region based on seismic wave calculation

    Energy Technology Data Exchange (ETDEWEB)

    Pribadi, Sugeng, E-mail: sugengpribadimsc@gmail.com [Badan Meteorologi Klimatologi Geofisika, Jl Angkasa I No. 2 Jakarta (Indonesia); Afnimar,; Puspito, Nanang T.; Ibrahim, Gunawan [Institut Teknologi Bandung, Jl. Ganesha 10, Bandung 40132 (Indonesia)

    2014-03-24

    This study is to characterize the source mechanism of tsunamigenic earthquake based on seismic wave calculation. The source parameter used are the ratio (Θ) between the radiated seismic energy (E) and seismic moment (M{sub o}), moment magnitude (M{sub W}), rupture duration (T{sub o}) and focal mechanism. These determine the types of tsunamigenic earthquake and tsunami earthquake. We calculate the formula using the teleseismic wave signal processing with the initial phase of P wave with bandpass filter 0.001 Hz to 5 Hz. The amount of station is 84 broadband seismometer with far distance of 30° to 90°. The 2 June 1994 Banyuwangi earthquake with M{sub W}=7.8 and the 17 July 2006 Pangandaran earthquake with M{sub W}=7.7 include the criteria as a tsunami earthquake which distributed about ratio Θ=−6.1, long rupture duration To>100 s and high tsunami H>7 m. The 2 September 2009 Tasikmalaya earthquake with M{sub W}=7.2, Θ=−5.1 and To=27 s which characterized as a small tsunamigenic earthquake.

  8. Characterization of tsunamigenic earthquake in Java region based on seismic wave calculation

    International Nuclear Information System (INIS)

    Pribadi, Sugeng; Afnimar,; Puspito, Nanang T.; Ibrahim, Gunawan

    2014-01-01

    This study is to characterize the source mechanism of tsunamigenic earthquake based on seismic wave calculation. The source parameter used are the ratio (Θ) between the radiated seismic energy (E) and seismic moment (M o ), moment magnitude (M W ), rupture duration (T o ) and focal mechanism. These determine the types of tsunamigenic earthquake and tsunami earthquake. We calculate the formula using the teleseismic wave signal processing with the initial phase of P wave with bandpass filter 0.001 Hz to 5 Hz. The amount of station is 84 broadband seismometer with far distance of 30° to 90°. The 2 June 1994 Banyuwangi earthquake with M W =7.8 and the 17 July 2006 Pangandaran earthquake with M W =7.7 include the criteria as a tsunami earthquake which distributed about ratio Θ=−6.1, long rupture duration To>100 s and high tsunami H>7 m. The 2 September 2009 Tasikmalaya earthquake with M W =7.2, Θ=−5.1 and To=27 s which characterized as a small tsunamigenic earthquake

  9. Did a slump source cause the 1929 Grand Banks tsunami?

    Science.gov (United States)

    Løvholt, F.; Schulten, I.; Mosher, D.; Harbitz, C. B.; Krastel, S.

    2017-12-01

    On November 18, 1929, a Mw 7.2 earthquake occurred beneath the upper Laurentian Fan, south of Newfoundland. The earthquake displaced about 100 km3 of sediment volume that rapidly evolved into a turbidity current revealed by a series of successive telecommunication cable breaks. A tsunami with fatal consequences along the south coast of Newfoundland also resulted. This tsunami is attributed to sediment mass failure as no seafloor displacement due to the earthquake is observed or expected. Although sidescan sonar, sub-bottom profiler and modern multibeam data show surficial sediment slumping and translational slide activity in the upper part of the slope, no major headscarp, single evacuation area or large mass transport deposit are observed. Sediment mass failure has been interpreted as broadly distributed and shallow, likely occurring in a retrogressive fashion. The question remained, therefore, as to how such complex failure kinematics could generate a tsunami. The Grand Banks tsunami is the only landslide tsunami for which traces are found at transoceanic distances. Despite being a landmark event, only a couple of attempts to model the tsunami exist. None of these have been able to match tsunami observations. Recently acquired seismic reflection data suggest that rotational slumping of a thick sediment mass ( 500 m) on the St. Pierre Slope may have occurred, causing seafloor displacements (fault traces) up to 100 m in height. The previously mapped surficial failures were a consequence of slumping of the thicker mass. Here, we simulate tsunami generation using the new geophysical information to construct different tsunamigenic slump sources. In addition, we undertake simulations assuming a flowing surficial landslide. The numerical simulations shows that its large and rapid vertical displacements render the slump source more tsunamigenic than the alternative surficial landslide. The simulations using the slump source roughly complies with observations of large run

  10. 2011 Tohoku Earthquake and Japan's Nuclear Disaster - Implications for Indian Ocean Rim countries

    Science.gov (United States)

    Chadha, R. K.

    2011-12-01

    The Nuclear disaster in Japan after the M9.0 Tohoku earthquake on March 11, 2011 has elicited global response to have a relook at the safety aspects of the nuclear power plants from all angles including natural hazards like earthquakes and tsunami. Several countries have gone into safety audits of their nuclear programs in view of the experience in Japan. Tectonically speaking, countries located close to subduction zones or in direct line of impact of the subduction zones are the most vulnerable to earthquake or tsunami hazard, as these regions are the locale of great tsunamigenic earthquakes. The Japan disaster has also cautioned to the possibility of great impact to the critical structures along the coasts due to other ocean processes caused by ocean-atmosphere interactions and also due to global warming and sea level rise phenomena in future. This is particular true for island countries. The 2011 Tohoku earthquake in Japan will be remembered more because of its nuclear tragedy and tsunami rather than the earthquake itself. The disaster happened as a direct impact of a tsunami generated by the earthquake 130 km off the coast of Sendai in the Honshu region of Japan. The depth of the earthquake was about 25 km below the ocean floor and it occurred on a thrust fault causing a displacement of more than 20 meters. At few places, water is reported to have inundated areas up to 8-10 km inland. The height of the tsunami varied between 10 and 3 meters along the coast. Generally, during an earthquake damage to buildings or other structures occur due to strong shaking which is expressed in the form of ground accelerations 'g'. Although, Peak Ground Accelerations (PGA) consistently exceeded 2g at several places from Sendai down south, structures at the Fukushima Daiichi Nuclear Power Plant did not collapse due to the earthquake. In the Indian Ocean Rim countries, Indian, Pakistan and South Africa are the three countries where Nuclear power plants are operational, few of them

  11. Mangrove forest against dyke-break-induced tsunami on rapidly subsiding coasts

    Science.gov (United States)

    Takagi, Hiroshi; Mikami, Takahito; Fujii, Daisuke; Esteban, Miguel; Kurobe, Shota

    2016-07-01

    Thin coastal dykes typically found in developing countries may suddenly collapse due to rapid land subsidence, material ageing, sea-level rise, high wave attack, earthquakes, landslides, or a collision with vessels. Such a failure could trigger dam-break tsunami-type flooding, or "dyke-break-induced tsunami", a possibility which has so far been overlooked in the field of coastal disaster science and management. To analyse the potential consequences of one such flooding event caused by a dyke failure, a hydrodynamic model was constructed based on the authors' field surveys of a vulnerable coastal location in Jakarta, Indonesia. In a 2 m land subsidence scenario - which is expected to take place in the study area after only about 10-20 years - the model results show that the floodwaters rapidly rise to a height of nearly 3 m, resembling the flooding pattern of earthquake-induced tsunamis. The depth-velocity product criterion suggests that many of the narrow pedestrian paths behind the dyke could experience strong flows, which are far greater than the safe limits that would allow pedestrian evacuation. A couple of alternative scenarios were also considered to investigate how such flood impacts could be mitigated by creating a mangrove belt in front of the dyke as an additional safety measure. The dyke-break-induced tsunamis, which in many areas are far more likely than regular earthquake tsunamis, cannot be overlooked and thus should be considered in disaster management and urban planning along the coasts of many developing countries.

  12. Earthquake-associated events. Annual safety research report, JFY 2011

    International Nuclear Information System (INIS)

    2012-01-01

    For the tsunami and slope stability as the earthquake-associated events that increased with the revision of the regulatory guide for reviewing seismic design of nuclear power reactor facilities, related technical standard and analysis code were leveled up to support the safety examination of the country. For tsunami study, the original plan was changed due to the 2011 Tohoku earthquake tsunami, analysis code of river run-up, sedimentation, probabilistic tsunami hazard and tsunami trace database were developed. For slope study, in addition to conventional stress criteria, in order to build a slope stability evaluation method, incorporating new indicators, such as deformation and strain, the following study was conducted. The large-scale shaking table test for E-defense, the test data were obtained. The applicability of slope stability analysis code was examined by using the shaking table test data. (author)

  13. Numerical Study on the 1682 Tainan Historic Tsunami Event

    Science.gov (United States)

    Tsai, Y.; Wu, T.; Lee, C.; KO, L.; Chuang, M.

    2013-12-01

    We intend to reconstruct the tsunami source of the 1682/1782 tsunami event in Tainan, Taiwan, based on the numerical method. According to Soloviev and Go (1974), a strong earthquake shook the Tainan and caused severe damage, followed by tsunami waves. Almost the whole island was flooded by tsunami for over 120 km. More than 40,000 inhabitants were killed. Forts Zealand and Pigchingi were washed away. 1682/1782 event was the highest death toll in the Pacific Ocean regarded by Bryant (2001). However, the year is ambiguous in 1682 or 1782, and death toll is doubtful. We tend to believe that this event was happened in 1682 based on the evolution of the harbor name. If the 1682 tsunami event does exist, the hazard mitigation plan has to be modified, and restoring the 1682 event becomes important. In this study, we adopted the tsunami reverse tracking method (TRTM) to examine the possible tsunami sources. A series of numerical simulations were carried out by using COMCOT (Cornell Multi-grid Coupled Tsunami model), and nested grid with 30 m resolution was applied to the study area. According to the result of TRTM, the 1682 tsunami is most likely sourcing from the north segment of Manila Trench. From scenario study, we concluded that the 1682 event was triggered by an Mw >= 8.8 earthquake in north segment of Manila Trench, and 4 m wave height was observed in Tainan and its inundation range is agreeable with historical records. If this scenario occurred again, sever damage and death toll will be seen many high population cities, such as Tainan city, Kaohsiung city and Kenting, where No. 3 nuclear power plant is located. Detailed results will be presented in the full paper. Figure 1. Map of Tsunami Reverse Tracking Method (TRTM) in Tainan. Black arrow indicates direction of possible tsunami direction. The color bar denotes the magnitude of the maximum moment flux. Figure 2. Scenario result of Mw 8.8 in northern segment of Manila Trench. (Left: Initial free surface elevation

  14. Standardized procedure for tsunami PRA by AESJ

    International Nuclear Information System (INIS)

    Kirimoto, Yukihiro; Yamaguchi, Akira; Ebisawa, Katsumi

    2013-01-01

    After Fukushima Accident (March 11, 2011), the Atomic Energy Society of Japan (AESJ) started to develop the standard of Tsunami Probabilistic Risk Assessment (PRA) for nuclear power plants in May 2011. As Japan is one of the countries with frequent earthquakes, a great deal of efforts has been made in the field of seismic research since the early stage. To our regret, the PRA procedures guide for tsunami has not yet been developed although the importance is held in mind of the PRA community. Accordingly, AESJ established a standard to specify the standardized procedure for tsunami PRA considering the results of investigation into the concept, the requirements that should have and the concrete methods regarding tsunami PRA referring the opinions of experts in the associated fields in December 2011 (AESJ-SC-RK004:2011). (author)

  15. Tsunami Ionospheric warning and Ionospheric seismology

    Science.gov (United States)

    Lognonne, Philippe; Rolland, Lucie; Rakoto, Virgile; Coisson, Pierdavide; Occhipinti, Giovanni; Larmat, Carene; Walwer, Damien; Astafyeva, Elvira; Hebert, Helene; Okal, Emile; Makela, Jonathan

    2014-05-01

    The last decade demonstrated that seismic waves and tsunamis are coupled to the ionosphere. Observations of Total Electron Content (TEC) and airglow perturbations of unique quality and amplitude were made during the Tohoku, 2011 giant Japan quake, and observations of much lower tsunamis down to a few cm in sea uplift are now routinely done, including for the Kuril 2006, Samoa 2009, Chili 2010, Haida Gwai 2012 tsunamis. This new branch of seismology is now mature enough to tackle the new challenge associated to the inversion of these data, with either the goal to provide from these data maps or profile of the earth surface vertical displacement (and therefore crucial information for tsunami warning system) or inversion, with ground and ionospheric data set, of the various parameters (atmospheric sound speed, viscosity, collision frequencies) controlling the coupling between the surface, lower atmosphere and the ionosphere. We first present the state of the art in the modeling of the tsunami-atmospheric coupling, including in terms of slight perturbation in the tsunami phase and group velocity and dependance of the coupling strength with local time, ocean depth and season. We then show the confrontation of modelled signals with observations. For tsunami, this is made with the different type of measurement having proven ionospheric tsunami detection over the last 5 years (ground and space GPS, Airglow), while we focus on GPS and GOCE observation for seismic waves. These observation systems allowed to track the propagation of the signal from the ground (with GPS and seismometers) to the neutral atmosphere (with infrasound sensors and GOCE drag measurement) to the ionosphere (with GPS TEC and airglow among other ionospheric sounding techniques). Modelling with different techniques (normal modes, spectral element methods, finite differences) are used and shown. While the fits of the waveform are generally very good, we analyse the differences and draw direction of future

  16. Far-field tsunami magnitude determined from ocean-bottom pressure gauge data around Japan

    Science.gov (United States)

    Baba, T.; Hirata, K.; Kaneda, Y.

    2003-12-01

    \\hspace*{3mm}Tsunami magnitude is the most fundamental parameter to scale tsunamigenic earthquakes. According to Abe (1979), the tsunami magnitude, Mt, is empirically related to the crest to trough amplitude, H, of the far-field tsunami wave in meters (Mt = logH + 9.1). Here we investigate the far-field tsunami magnitude using ocean-bottom pressure gauge data. The recent ocean-bottom pressure measurements provide more precise tsunami data with a high signal-to-noise ratio. \\hspace*{3mm}Japan Marine Science and Technology Center is monitoring ocean bottom pressure fluctuations using two submarine cables of depths of 1500 - 2400 m. These geophysical observatory systems are located off Cape Muroto, Southwest Japan, and off Hokkaido, Northern Japan. The ocean-bottom pressure data recorded with the Muroto and Hokkaido systems have been collected continuously since March, 1997 and October, 1999, respectively. \\hspace*{3mm}Over the period from March 1997 to June 2003, we have observed four far-field tsunami signals, generated by earthquakes, on ocean-bottom pressure records. These far-field tsunamis were generated by the 1998 Papua New Guinea eq. (Mw 7.0), 1999 Vanuatu eq. (Mw 7.2), 2001 Peru eq. (Mw 8.4) and 2002 Papua New Guinea eq. (Mw 7.6). Maximum amplitude of about 30 mm was recorded by the tsunami from the 2001 Peru earthquake. \\hspace*{3mm}Direct application of the Abe's empirical relation to ocean-bottom pressure gauge data underestimates tsunami magnitudes by about an order of magnitude. This is because the Abe's empirical relation was derived only from tsunami amplitudes with coastal tide gauges where tsunami is amplified by the shoaling of topography and the reflection at the coastline. However, these effects do not work for offshore tsunami in deep oceans. In general, amplification due to shoaling near the coastline is governed by the Green's Law, in which the tsunami amplitude is proportional to h-1/4, where h is the water depth. Wave amplitude also is

  17. A plan for safety evaluation of tsunamis at the Uljin nuclear power plant site

    International Nuclear Information System (INIS)

    Lee, H. K.; Lee, D. S.

    1999-01-01

    The sites of many nuclear and thermal power plants are located along the coast line to obtain necessary cooling water. Therefore, they are vulnerable to coastal disasters like tsunamis. The safety evaluation on tsunamis of the site of Uljin nuclear power plants was performed with the maximum potential earthquake magnitude and related fault parameters in 1986. But according to the results of recent research, the possibility was suggested that the earthquake which has bigger magnitude than was expected is likely to happen in the seismic gaps near Akita, Japan. Therefore, a plan for safety evaluation of tsunamis at the Uljin nuclear power plants was laid out

  18. LOCAL SITE CONDITIONS INFLUENCING EARTHQUAKE INTENSITIES AND SECONDARY COLLATERAL IMPACTS IN THE SEA OF MARMARA REGION - Application of Standardized Remote Sensing and GIS-Methods in Detecting Potentially Vulnerable Areas to Earthquakes, Tsunamis and Other Hazards.

    Directory of Open Access Journals (Sweden)

    George Pararas-Carayannis

    2011-01-01

    Full Text Available The destructive earthquake that struck near the Gulf of Izmit along the North Anatolian fault in Northwest Turkey on August 17, 1999, not only generated a local tsunami that was destructive at Golcuk and other coastal cities in the eastern portion of the enclosed Sea of Marmara, but was also responsible for extensive damage from collateral hazards such as subsidence, landslides, ground liquefaction, soil amplifications, compaction and underwater slumping of unconsolidated sediments. This disaster brought attention in the need to identify in this highly populated region, local conditions that enhance earthquake intensities, tsunami run-up and other collateral disaster impacts. The focus of the present study is to illustrate briefly how standardized remote sensing techniques and GIS-methods can help detect areas that are potentially vulnerable, so that disaster mitigation strategies can be implemented more effectively. Apparently, local site conditions exacerbate earthquake intensities and collateral disaster destruction in the Marmara Sea region. However, using remote sensing data, the causal factors can be determined systematically. With proper evaluation of satellite imageries and digital topographic data, specific geomorphologic/topographic settings that enhance disaster impacts can be identified. With a systematic GIS approach - based on Digital Elevation Model (DEM data - geomorphometric parameters that influence the local site conditions can be determined. Digital elevation data, such as SRTM (Shuttle Radar Topography Mission, with 90m spatial resolution and ASTER-data with 30m resolution, interpolated up to 15 m is readily available. Areas with the steepest slopes can be identified from slope gradient maps. Areas with highest curvatures susceptible to landslides can be identified from curvature maps. Coastal areas below the 10 m elevation susceptible to tsunami inundation can be clearly delineated. Height level maps can also help locate

  19. A review on earthquake and tsunami hazards of the Sumatran plate boundary: Observing expected and unexpected events after the Aceh-Andaman Mw 9.15 event

    Science.gov (United States)

    Natawidjaja, D.

    2013-12-01

    The 600-km Mentawai megathrust had produced two giant historical earthquakes generating big tsunamies in 1797 and 1833. The SuGAr (Sumatran GPS continuous Array) network, first deployed in 2002, shows that the subduction interface underlying Mentawai Islands and the neighboring Nias section in the north are fully locked, thus confirming their potential hazards. Outreach activities to warn people about earthquake and tsunamies had been started since 4 months prior to the 26 December 2004 in Aceh-Andaman earthquake (Mw 9.15). Later in March 2005, the expected megathrust earthquake (Mw 8.7) hit Nias-Simelue area and killed about 2000 people, releasing the accumulated strain since the previous 1861 event (~Mw 8.5). After then many Mw 7s and smaller events occured in Sumatra, filling areas between and around two giant ruptures and heighten seismicities in neighboring areas. In March 2007, the twin earthquake disaster (Mw 6.3 and Mw 6.4) broke two consecutive segments of the transcurrent Sumatran fault in the Singkarak lake area. Only six month later, in September 2007, the rapid-fire-failures of three consecutive megathrust patches (Mw 8.5, Mw 7.9 and Mw 7.0) ruptured a 250-km-section of the southern part of the Mentawai. It was a big surprise since this particular section is predicted as a very-low coupled section from modelling the SuGAr data, and hence, bypassing the more potential fully coupled section of the Mentawai in between the 2005 and 2007 ruptures. In September 2009, a rare unexpected event (Mw 7.6) suddenly ruptured an intracrustal fault in the subducted slab down under Padang City and killed about 500 people. Padang had been in preparation for the next tsunami but not for strong shakes from near by major earthquake. This event seems to have remotely triggered another Mw 6.7 on the Sumatran fault near kerinci Lake, a few hundred kilometers south of Padang, in less than a day. Just a year later, in November 2010, again an unexpected large slow-slip event of

  20. Community exposure to tsunami hazards in Hawai‘i

    Science.gov (United States)

    Jones, Jamie L.; Jamieson, Matthew R.; Wood, Nathan J.

    2016-06-17

    Hawai‘i has experienced numerous destructive tsunamis and the potential for future inundation has been described over the years using various historical events and scenarios. To support tsunami preparedness and risk-reduction planning in Hawai‘i, this study documents the variations among 91 coastal communities and 4 counties in the amounts, types, and percentages of developed land, residents, employees, community-support businesses, dependent-care facilities, public venues, and critical facilities in a composite extreme tsunami-inundation zone associated with two great Aleutian moment magnitude (Mw) 9.3 and 9.6 earthquake scenarios. These earthquake scenarios are considered to provide the maximum tsunami scenario for the Hawaiian Islands. According to 2010 U.S. Census Bureau data, the Hawai‘i extreme tsunami-inundation zone contains approximately 248,749 residents and 91,528 households (18 and 20 percent, respectively, of State totals). The residential population in tsunami-prone areas is racially diverse, with most residents identifying themselves as White (47 percent of the total exposed population), Asian (48 percent), or Native Hawaiian and Other Pacific Islander (29 percent), either alone or in combination with one or more other races (note that race categories do not sum to 100 percent because individuals were able to report multiple races in the 2010 U.S. Census). A total of 50,016 households are renter-occupied, making up 55 percent of total households in the extreme inundation zone. The extreme tsunami-inundation zone contains 18,693 businesses (37 percent of State totals) and 245,827 employees (42 percent of the State labor force). The employee population in the extreme tsunami-inundation zone is largely in the accommodation and food services and retail-trade sectors. Although occupancy values are not known for each facility, the extreme tsunami-inundation zone also contains numerous community-support businesses (for example, religious organizations

  1. Engineering Applications Using Probabilistic Aftershock Hazard Analyses: Aftershock Hazard Map and Load Combination of Aftershocks and Tsunamis

    Directory of Open Access Journals (Sweden)

    Byunghyun Choi

    2017-12-01

    Full Text Available After the Tohoku earthquake in 2011, we observed that aftershocks tended to occur in a wide region after such a large earthquake. These aftershocks resulted in secondary damage or delayed rescue and recovery activities. In addition, it has been reported that there are regions where the intensity of the vibrations owing to the aftershocks was much stronger than those associated with the main shock. Therefore, it is necessary to consider the seismic risk associated with aftershocks. We used the data regarding aftershocks that was obtained from the Tohoku earthquake and various other historically large earthquakes. We investigated the spatial and temporal distribution of the aftershocks using the Gutenberg–Richter law and the modified Omori law. Subsequently, we previously proposed a probabilistic aftershock occurrence model that is expected to be useful to develop plans for recovery activities after future large earthquakes. In this study, the probabilistic aftershock hazard analysis is used to create aftershock hazard maps. We propose a hazard map focusing on the probability of aftershocks on the scale of the main shock for use with a recovery activity plan. Following the lessons learned from the 2011 Tohoku earthquake, we focus on the simultaneous occurrence of tsunamis and aftershocks just after a great subduction earthquake. The probabilistic aftershock hazard analysis is used to derive load combination equations of the load and resistance factor design. This design is intended to simultaneously consider tsunamis and aftershocks for tsunami-resistant designs of tsunami evacuation buildings.

  2. A Reverse Tracking Method to Analyze the 1867 Keelung Tsunami Event

    Science.gov (United States)

    Lee, C.; Wu, T.; Tsai, Y.; KO, L.; Chuang, M.

    2013-12-01

    The 1867 Keelung tsunami is the only tsunami event verified by Taiwan government. This event caused serious damage and hundreds death toll in northern Taiwan, including the Keelung city, Jinshan and Patoutzu areas (Fig. 1). This event is not only recorded in many literatures, but also unveiled by sedimentary evidence. In addition, this event also indicates that the three nuclear power plants nearby are prone to tsunami attacks (Fig. 1). The previous studies consider that this tsunami might be generated by a Mw 7.0 earthquake which might occur along the Shanchiao Fault (Zheng et al, 2011). However, there is no evidence showing the relationship between these geological activities and the tsunami event. In this study, we intend to find the potential tsunami source through numerical analysis. We conducted series of numerical experiments by using sets of fault parameters from Mw 7.0 to Mw 8.0. However, none of them was able to explain the 7 m tsunami height observed in history and the sedimentary evidence found on the Hoping Island. Considering the steep bathymetry and intense volcanic activity along the Keelung coast, one reasonable hypothesis is that the earthquake or volcanic eruption triggered a submarine landslide which increased the tsunami height dramatically. In order to confirm this scenario, we performed the Reverse Tracking Method (RTM), based on the linear hypothesis of tsunami wave propagation, to find the possible locations of the tsunami sources (Fig. 1). The Cornell Multi-grid Coupled Tsunami Model (COMCOT) was then used to perform the tsunami simulations. We followed the Mw 7.0 earthquake proposed by Lin et al. (2006) and added the landslide disturbance (Watts et al., 2005). The source-scaling relationship proposed by Yen and Ma (2011) was used to determine the fault parameters. In addition to the Shanchiao Fault, five submarine volcanos and three submarine canyons were considered as the potential tsunami sources. The result shows that the 1867 tsunami

  3. Development of a Tsunami Scenario Database for Marmara Sea

    Science.gov (United States)

    Ozer Sozdinler, Ceren; Necmioglu, Ocal; Meral Ozel, Nurcan

    2016-04-01

    Due to the very short travel times in Marmara Sea, a Tsunami Early Warning System (TEWS) has to be strongly coupled with the earthquake early warning system and should be supported with a pre-computed tsunami scenario database to be queried in near real-time based on the initial earthquake parameters. To address this problem, 30 different composite earthquake scenarios with maximum credible Mw values based on 32 fault segments have been identified to produce a detailed scenario database for all possible earthquakes in the Marmara Sea with a tsunamigenic potential. The bathy/topo data of Marmara Sea was prepared using GEBCO and ASTER data, bathymetric measurements along Bosphorus, Istanbul and Dardanelle, Canakkale and the coastline digitized from satellite images. The coarser domain in 90m-grid size was divided into 11 sub-regions having 30m-grid size in order to increase the data resolution and precision of the calculation results. The analyses were performed in nested domains with numerical model NAMIDANCE using non-linear shallow water equations. In order to cover all the residential areas, industrial facilities and touristic locations, more than 1000 numerical gauge points were selected along the coasts of Marmara Sea, which are located at water depth of 5 to 10m in finer domain. The distributions of tsunami hydrodynamic parameters were investigated together with the change of water surface elevations, current velocities, momentum fluxes and other important parameters at the gauge points. This work is funded by the project MARsite - New Directions in Seismic Hazard assessment through Focused Earth Observation in the Marmara Supersite (FP7-ENV.2012 6.4-2, Grant 308417 - see NH2.3/GMPV7.4/SM7.7) and supported by SATREPS-MarDim Project (Earthquake and Tsunami Disaster Mitigation in the Marmara Region and Disaster Education in Turkey) and JICA (Japan International Cooperation Agency). The authors would like to acknowledge Ms. Basak Firat for her assistance in

  4. PEMETAAN BAHAYA GEMPA BUMI DAN POTENSI TSU-NAMI DI BALI BERDASARKAN NILAI SEISMISITAS

    Directory of Open Access Journals (Sweden)

    Bayu Baskara

    2017-02-01

    Full Text Available Bali is one of the areas prone to earthquake and tsunami as being at the junction of two plates, namely the Eurasian plate and the Indo-Australian plate is located in the south of Bali and back arc trust zones are located in the North of Bali. We need research on the potential dangers of earthquakes and tsunami in Bali are based on the value of seismicity which is interpreted by the value of b and a. This study uses earthquake data on the coordinates 6?-11? SLand 114?-116? EL with 339 data that was processed using Zmap in order to obtain the value of b at 1.57 ± 0.008 and the value of a is 10.6 and maximum magnitude of 7.1 Mw. From mapping the values ??of b and a known area that has the highest value of b and a lies in the sea area to the south of Bali, Karangasem and Buleleng to the northern region of Bali. Furthermore, for mapping the tsunami in Bali using the TOAST application obtained tsunami prone areas of Bali, Kuta Beach, East Buleleng and Karangasem.

  5. Numerical modeling of the 1964 Alaska tsunami in western Passage Canal and Whittier, Alaska

    Directory of Open Access Journals (Sweden)

    D. J. Nicolsky

    2010-12-01

    Full Text Available A numerical model of the wave dynamics in Passage Canal, Alaska during the Mw 9.2 megathrust earthquake is presented. During the earthquake, several types of waves were identified at the city of Whittier, located at the head of Passage Canal. The first wave is thought to have been a seiche, while the other two waves were probably triggered by submarine landslides. We model the seiche wave, landslide-generated tsunami, and tectonic tsunami in Passage Canal and compute inundation by each type of wave during the 1964 event. Modeled results are compared with eyewitness reports and an observed inundation line. Results of the numerical experiments let us identify where the submarine landslides might have occurred during the 1964 event. We identify regions at the head and along the northern shore of Passage Canal, where landslides triggered a wave that caused most of the damage in Whittier. An explanation of the fact that the 1964 tectonic tsunami in Whittier was unnoticed is presented as well. The simulated inundation by the seiche, landslide-generated tsunami, and tectonic tsunami can help to mitigate tsunami hazards and prepare Whittier for a potential tsunami.

  6. Precise Positioning of BDS, BDS/GPS: Implications for Tsunami Early Warning in South China Sea

    Directory of Open Access Journals (Sweden)

    Kejie Chen

    2015-11-01

    Full Text Available Global Positioning System (GPS has been proved to be a powerful tool for measuring co-seismic ground displacements with an application to seismic source inversion. Whereas most of the tsunamis are triggered by large earthquakes, GPS can contribute to the tsunami early warning system (TEWS by helping to obtain tsunami source parameters in near real-time. Toward the end of 2012, the second phase of the BeiDou Navigation Satellite System (BDS constellation was accomplished, and BDS has been providing regional positioning service since then. Numerical results indicate that precision of BDS nowadays is equivalent to that of the GPS. Compared with a single Global Satellite Navigation System (GNSS, combined BDS/GPS real-time processing can improve accuracy and especially reliability of retrieved co-seismic displacements. In the present study, we investigate the potential of BDS to serve for the early warning system of tsunamis in the South China Sea region. To facilitate early warnings of tsunamis and forecasting capabilities in this region, we propose to distribute an array of BDS-stations along the Luzon Island (Philippines. By simulating an earthquake with Mw = 8 at the Manila trench as an example, we demonstrate that such an array will be able to detect earthquake parameters in real time with a high degree of accuracy and, hence, contribute to the fast and reliable tsunami early warning system in this region.

  7. Tsunami hazard assessment in La Reunion and Mayotte Islands in the Indian Ocean : detailed modeling of tsunami impacts for the PREPARTOI project

    Science.gov (United States)

    Quentel, E.; Loevenbruck, A.; Sahal, A.; Lavigne, F.

    2011-12-01

    Significant tsunamis have often affected the southwest Indian Ocean. The scientific project PREPARTOI (Prévention et REcherche pour l'Atténuation du Risque Tsunami dans l'Océan Indien), partly founded by the MAIF foundation, aims at assessing the tsunami risk on both french islands of this region, La Réunion and Mayotte. Further purpose of this project is the detailed hazard and vulnerability study for specific places of these islands, selected according to their environmental and human issues and observed impacts of past tsunamis. Tsunami hazard in this region, recently highlighted by major events in the southwest Indian Ocean, has never been thoroughly evaluated. Our study, within the PREPARTOI project, contributes to fill in this lack. It aims at examining transoceanic tsunami hazard related to earthquakes by modeling the scenarios of major historical events. We consider earthquakes with magnitude greater than Mw 7.7 located on the Sumatra (1833, 2004, 2010), Java (2006) and Makran (1945) subduction zones. First, our simulations allow us to compare the tsunami impact at regional scale according to the seismic sources; we thus identify earthquakes locations which most affect the islands and describe the impact distribution along their coastline. In general, we note that, for the same magnitude, events coming from the southern part of Sumatra subduction zone induce a larger impact than the north events. The studied tsunamis initiated along the Java and Makran subduction zones have limited effects on both French islands. Then, detailed models for the selected sites are performed based on high resolution bathymetric and topographic data; they provide estimations of the water currents, the water heights and the potential inundations. When available, field measurements and maregraphic records allow testing our models. Arrival time, amplitude of the first wave and impact on the tide gauge time series are well reproduced. Models are consistent with the observations

  8. Tsunami Disaster Risk Assessment and Prevention in West Java, Indonesia

    Science.gov (United States)

    Deng, H.; Harris, R. A.; Horns, D. M.; Yulianto, E.; Bunds, M. P.; Prasetyadi, C.; Emmett, C.; Hall, S.

    2016-12-01

    Java Island, Indonesia is the most populated area and one of the most tectonically active coastal nations on Earth. This island is the volcanic arc and accretionary wedge of the subduction zone of the Sunda and the Australia plate, where the Java Trench is located. However, the Java Trench hasn't had a mega or giant earthquake for at least 430 years according to historical records. Up to 30 m of slip may have accumulated on the subduction zone interface during this time, which is enough to produce a Mw 9.0 earthquake and large tsunami. One of the largest seismic gaps along the Sunda Arc is a 640 km section of the coast of west Java. The largest population center in this region is Pelabuhan Ratu, with is partially built on ridge and swale coastal plain topography. Candidate tsunami deposits were found in swales that may indicate inundation up to 1 km inland. Numerical modeling of various possible tsunami scenarios indicate that the configuration of the coastline may amplify a tsunami and cause high run-up in the most populated areas or the coast. Also, data from questionnaire surveys administered in Pelabuhan Ratu show a lack of awareness about how tsunamis threaten these communities and plans of action.

  9. Paleographical, Bathymetric and Numerical Investigations for a Tsunami Possibly Caused by Submarine Mass Failure in the Nankai Trough, Japan

    Science.gov (United States)

    Baba, T.; Ashi, J.; Kanamatsu, T.; Imai, K.; Yamashita, K.

    2017-12-01

    "SHINCHO-KI" is an ancient document that records tsunami damages caused by the 1512 Eisho earthquake, the 1605 Keicho earthquake, the 1707 Hoei earthquake and the 1854 Ansei-Nankai earthquake in Shishikui, where is located along the coast of the southeastern part of Shikoku, facing to the Nankai trough. According to SHINCHO-KI, 3700 people were dead in Shishikui by the tsunami during the 1512 Eisho earthquake. However, no evidence was found for the occurrence of the 1512 Eisho earthquake except for SHINCHO-KI, while the other earthquakes were recorded in many ancient documents in the southwestern Japan. To investigate the source mechanism of the 1512 Eisho earthquake, we carefully read a bathymetric chart and found a scarp with a height of about 400 m and a width of about 6000 m at a position about 24 km offshore in the southeastern direction from Shishikui. We also carried out a survey by using a deep-towed sub-bottom profiler (SBP) on ROV NSS during the R/V Hakuho-maru KH-16-5 cruise. The result shows detailed structures possibly caused by a recent landslide. The vertical displacement of the strata was measured to be about 50 m. By considering these results, we simulated the 1512 Eisho tsunami generated by a submarine mass failure. The topographic data in Shishikui which is needed in the calculation was made from the present data. But we removed the artificial structures such as wave breakers and altered coastlines by referring to old map images. In the numerical simulation, the initial sea surface deformation was obtained by the method proposed by Watts et al. (2005), and the tsunami propagation was calculated by solving the nonlinear shallow water equations with dispersive (Boussinesq) term on a finite difference scheme. We solved the advection terms by using the third-order upwind difference to avoid artificial viscosity. The numerical simulation estimated the maximum tsunami height of about 6m and moderate inundation on land in Shishikui by the 1512 Eisho

  10. The Hellenic National Tsunami Warning Centre (HL-NTWC): Recent updates and future developments

    Science.gov (United States)

    Melis, Nikolaos S.; Charalampakis, Marinos

    2014-05-01

    The Hellenic NTWC (HL-NTWC) was established officially by Greek Law in September 2010. HL-NTWC is hosted at the National Observatory of Athens, Institute of Geodynamics (NOA-IG), which also operates a 24/7 earthquake monitoring service in Greece and coordinates the newly established Hellenic Unified National Seismic Network. NOA-IG and HL-NTWC Operational Centre is linked to the Civil Protection Operational Centre and serves as the official alerting agency to the General Secretariat for Civil Protection in Greece, regarding earthquake events and tsunami watch. Since August 2012, HL-NTWC acts as Candidate Tsunami Watch Provider (CTWP) under the UNESCO IOC - ICG NEAMTWS tsunami warning system (NEAM: North-Eastern Atlantic, the Mediterranean and connected seas) and offers its services to the NEAMTWS system. HL-NTWC has participated in all Communication Test Exercises (CTE) under NEAMTWS and also it has provided tsunami scenarios for extended system testing exercises such as NEAMWAVE12. Some of the recent developments at HL-NTWC in Greece include: deployment of new tide gauge stations for tsunami watch purposes, computation of tsunami scenarios and extending the database in use, improving alerting response times, earthquake magnitude estimation and testing newly established software modules for tsunami and earthquake alerting (i.e. Early-Est, SeisComP3 etc.) in Greece and the Eastern Mediterranean. Although funding today is limited, an advantage of the participation in important EC funded research projects, i.e. NERIES, NERA, TRANSFER, NEAMTIC and ASTARTE, demonstrates that collaboration of top class Research Institutions that care to produce important and useful results in the research front in Europe, can facilitate towards developing and operating top class Operational Centers, useful for Civil Protection purposes in regions in need. Last, it is demonstrated that HL-NTWC collaboration with important key role Research Centers in the Security and Safety issues (e

  11. The 26 December 2004 Sumatra tsunami recorded on the coast of ...

    African Journals Online (AJOL)

    Analysis of sea-level data obtained from the Atlantic Global Sea Level Observing System (GLOSS) sea-level station at Takoradi, Ghana, West Africa, clearly reveals a tsunami signal associated with the Mw = 9.3 Sumatra earthquake of 26 December 2004 in the Indian Ocean. The tsunami arrived at this location on 27 ...

  12. A Preliminary Tsunami vulnerability analysis for Bakirkoy district in Istanbul

    Science.gov (United States)

    Tufekci, Duygu; Lutfi Suzen, M.; Cevdet Yalciner, Ahmet; Zaytsev, Andrey

    2016-04-01

    Resilience of coastal utilities after earthquakes and tsunamis has major importance for efficient and proper rescue and recovery operations soon after the disasters. Vulnerability assessment of coastal areas under extreme events has major importance for preparedness and development of mitigation strategies. The Sea of Marmara has experienced numerous earthquakes as well as associated tsunamis. There are variety of coastal facilities such as ports, small craft harbors, and terminals for maritime transportation, water front roads and business centers mainly at North Coast of Marmara Sea in megacity Istanbul. A detailed vulnerability analysis for Yenikapi region and a detailed resilience analysis for Haydarpasa port in Istanbul have been studied in previously by Cankaya et al., (2015) and Aytore et al., (2015) in SATREPS project. In this study, the methodology of vulnerability analysis under tsunami attack given in Cankaya et al., (2015) is modified and applied to Bakirkoy district of Istanbul. Bakirkoy district is located at western part of Istanbul and faces to the North Coast of Marmara Sea from 28.77oE to 28.89oE. High resolution spatial dataset of Istanbul Metropolitan Municipality (IMM) is used and analyzed. The bathymetry and topography database and the spatial dataset containing all buildings/structures/infrastructures in the district are collated and utilized for tsunami numerical modeling and following vulnerability analysis. The tsunami parameters from deterministically defined worst case scenarios are computed from the simulations using tsunami numerical model NAMI DANCE. The vulnerability assessment parameters in the district according to vulnerability and resilience are defined; and scored by implementation of a GIS based TVA with appropriate MCDA methods. The risk level is computed using tsunami intensity (level of flow depth from simulations) and TVA results at every location in Bakirkoy district. The preliminary results are presented and discussed

  13. Tsunami hazard map in eastern Bali

    International Nuclear Information System (INIS)

    Afif, Haunan; Cipta, Athanasius

    2015-01-01

    Bali is a popular tourist destination both for Indonesian and foreign visitors. However, Bali is located close to the collision zone between the Indo-Australian Plate and Eurasian Plate in the south and back-arc thrust off the northern coast of Bali resulted Bali prone to earthquake and tsunami. Tsunami hazard map is needed for better understanding of hazard level in a particular area and tsunami modeling is one of the most reliable techniques to produce hazard map. Tsunami modeling conducted using TUNAMI N2 and set for two tsunami sources scenarios which are subduction zone in the south of Bali and back thrust in the north of Bali. Tsunami hazard zone is divided into 3 zones, the first is a high hazard zones with inundation height of more than 3m. The second is a moderate hazard zone with inundation height 1 to 3m and the third is a low tsunami hazard zones with tsunami inundation heights less than 1m. Those 2 scenarios showed southern region has a greater potential of tsunami impact than the northern areas. This is obviously shown in the distribution of the inundated area in the south of Bali including the island of Nusa Penida, Nusa Lembongan and Nusa Ceningan is wider than in the northern coast of Bali although the northern region of the Nusa Penida Island more inundated due to the coastal topography

  14. Tsunami hazard map in eastern Bali

    Energy Technology Data Exchange (ETDEWEB)

    Afif, Haunan, E-mail: afif@vsi.esdm.go.id [Geological Agency, Bandung (Indonesia); Cipta, Athanasius [Geological Agency, Bandung (Indonesia); Australian National University, Canberra (Australia)

    2015-04-24

    Bali is a popular tourist destination both for Indonesian and foreign visitors. However, Bali is located close to the collision zone between the Indo-Australian Plate and Eurasian Plate in the south and back-arc thrust off the northern coast of Bali resulted Bali prone to earthquake and tsunami. Tsunami hazard map is needed for better understanding of hazard level in a particular area and tsunami modeling is one of the most reliable techniques to produce hazard map. Tsunami modeling conducted using TUNAMI N2 and set for two tsunami sources scenarios which are subduction zone in the south of Bali and back thrust in the north of Bali. Tsunami hazard zone is divided into 3 zones, the first is a high hazard zones with inundation height of more than 3m. The second is a moderate hazard zone with inundation height 1 to 3m and the third is a low tsunami hazard zones with tsunami inundation heights less than 1m. Those 2 scenarios showed southern region has a greater potential of tsunami impact than the northern areas. This is obviously shown in the distribution of the inundated area in the south of Bali including the island of Nusa Penida, Nusa Lembongan and Nusa Ceningan is wider than in the northern coast of Bali although the northern region of the Nusa Penida Island more inundated due to the coastal topography.

  15. Tsunami hazard map in eastern Bali

    Science.gov (United States)

    Afif, Haunan; Cipta, Athanasius

    2015-04-01

    Bali is a popular tourist destination both for Indonesian and foreign visitors. However, Bali is located close to the collision zone between the Indo-Australian Plate and Eurasian Plate in the south and back-arc thrust off the northern coast of Bali resulted Bali prone to earthquake and tsunami. Tsunami hazard map is needed for better understanding of hazard level in a particular area and tsunami modeling is one of the most reliable techniques to produce hazard map. Tsunami modeling conducted using TUNAMI N2 and set for two tsunami sources scenarios which are subduction zone in the south of Bali and back thrust in the north of Bali. Tsunami hazard zone is divided into 3 zones, the first is a high hazard zones with inundation height of more than 3m. The second is a moderate hazard zone with inundation height 1 to 3m and the third is a low tsunami hazard zones with tsunami inundation heights less than 1m. Those 2 scenarios showed southern region has a greater potential of tsunami impact than the northern areas. This is obviously shown in the distribution of the inundated area in the south of Bali including the island of Nusa Penida, Nusa Lembongan and Nusa Ceningan is wider than in the northern coast of Bali although the northern region of the Nusa Penida Island more inundated due to the coastal topography.

  16. Network Structure and Community Evolution on Twitter: Human Behavior Change in Response to the 2011 Japanese Earthquake and Tsunami

    Science.gov (United States)

    Lu, Xin; Brelsford, Christa

    2014-10-01

    To investigate the dynamics of social networks and the formation and evolution of online communities in response to extreme events, we collected three datasets from Twitter shortly before and after the 2011 earthquake and tsunami in Japan. We find that while almost all users increased their online activity after the earthquake, Japanese speakers, who are assumed to be more directly affected by the event, expanded the network of people they interact with to a much higher degree than English speakers or the global average. By investigating the evolution of communities, we find that the behavior of joining or quitting a community is far from random: users tend to stay in their current status and are less likely to join new communities from solitary or shift to other communities from their current community. While non-Japanese speakers did not change their conversation topics significantly after the earthquake, nearly all Japanese users changed their conversations to earthquake-related content. This study builds a systematic framework for investigating human behaviors under extreme events with online social network data and our findings on the dynamics of networks and communities may provide useful insight for understanding how patterns of social interaction are influenced by extreme events.

  17. A comparison between two inundation models for the 25 Ooctober 2010 Mentawai Islands Tsunami

    Science.gov (United States)

    Huang, Z.; Borrero, J. C.; Qiu, Q.; Hill, E. M.; Li, L.; Sieh, K. E.

    2011-12-01

    On 25 October 2010, an Mw~7.8 earthquake occurred on the Sumatra megathrust seaward of the Mentawai Islands, Indonesia, generating a tsunami which killed approximately 500 people. Following the event, the Earth Observatory of Singapore (EOS) initiated a post-tsunami field survey, collecting tsunami run-up data from more than 30 sites on Pagai Selatan, Pagai Utara and Sipora. The strongest tsunami effects were observed on several small islands offshore of Pagai Selatan, where runup exceeded 16 m. This presentation will focus on a detailed comparison between two tsunami propagation and inundation models: COMCOT (Cornell Multi-grid Coupled Tsunami model) and MOST (Method of Splitting Tsunami). Simulations are initialized using fault models based on data from a 1-hz GPS system that measured co-seismic deformation throughout the region. Preliminary simulations suggest that 2-m vertical seafloor deformation over a reasonably large area is required to recreate most of the observed tsunami effects. Since the GPS data suggest that subsidence of the islands is small, this implies that the tsunami source region is somewhat narrower and located further offshore than described in recently published earthquake source models based on teleseismic inversions alone. We will also discuss issues such as bathymetric and topographic data preparation and the uncertainty in the modeling results due to the lack of high resolution bathymetry and topography in the study area.

  18. Implementation Of Haversine Formula And Best First Search Method In Searching Of Tsunami Evacuation Route

    Science.gov (United States)

    Anisya; Yoga Swara, Ganda

    2017-12-01

    Padang is one of the cities prone to earthquake disaster with tsunami due to its position at the meeting of two active plates, this is, a source of potentially powerful earthquake and tsunami. Central government and most offices are located in the red zone (vulnerable areas), it will also affect the evacuation of the population during the earthquake and tsunami disaster. In this study, researchers produced a system of search nearest shelter using best-first-search method. This method uses the heuristic function, the amount of cost taken and the estimated value or travel time, path length and population density. To calculate the length of the path, researchers used method of haversine formula. The value obtained from the calculation process is implemented on a web-based system. Some alternative paths and some of the closest shelters will be displayed in the system.

  19. Introduction to "Global Tsunami Science: Past and Future, Volume II"

    Science.gov (United States)

    Rabinovich, Alexander B.; Fritz, Hermann M.; Tanioka, Yuichiro; Geist, Eric L.

    2017-08-01

    Twenty-two papers on the study of tsunamis are included in Volume II of the PAGEOPH topical issue "Global Tsunami Science: Past and Future". Volume I of this topical issue was published as PAGEOPH, vol. 173, No. 12, 2016 (Eds., E. L. Geist, H. M. Fritz, A. B. Rabinovich, and Y. Tanioka). Three papers in Volume II focus on details of the 2011 and 2016 tsunami-generating earthquakes offshore of Tohoku, Japan. The next six papers describe important case studies and observations of recent and historical events. Four papers related to tsunami hazard assessment are followed by three papers on tsunami hydrodynamics and numerical modelling. Three papers discuss problems of tsunami warning and real-time forecasting. The final set of three papers importantly investigates tsunamis generated by non-seismic sources: volcanic explosions, landslides, and meteorological disturbances. Collectively, this volume highlights contemporary trends in global tsunami research, both fundamental and applied toward hazard assessment and mitigation.

  20. Prediction of Tsunami Inundation in the City of Lisbon (portugal)

    Science.gov (United States)

    Baptista, M.; Miranda, J.; Omira, R.; Catalao Fernandes, J.

    2010-12-01

    Lisbon city is located inside the estuary of Tagus river, 20 km away from the Atlantic ocean. The city suffered great damage from tsunamis and its downtown was flooded at least twice in 1531 and 1755. Since the installation of the tide-gage network, in the area, three tsunamis caused by submarine earthquakes, were recorded in November 1941, February 1969 and May 1975. The most destructive tsunamis listed along Tagus Estuary are the 26th January 1531, a local tsunami event restricted to the Tagus Estuary, and the well known 1st November 1755 transoceanic event, both following highly destructive earthquakes, which deeply affected Lisbon. The economic losses due to the impact of the 1755 tsunami in one of Europe’s 18t century main harbor and commercial fleets were enormous. Since then the Tagus estuary suffered strong morphologic changes manly due to dredging works, construction of commercial and industrial facilities and recreational docks, some of them already projected to preserve Lisbon. In this study we present preliminary inundation maps for the Tagus estuary area in the Lisbon County, for conditions similar to the 1755 tsunami event, but using present day bathymetric and topographic maps. Inundation modelling is made using non linear shallow water theory and the numerical code is based upon COMCOT code. Nested grids resolutions used in this study are 800 m, 200 m and 50 m, respectively. The inundation is discussed in terms of flow depth, run up height, maximum inundation area and current flow velocity. The effects of estuary modifications on tsunami propagation are also investigated.

  1. Non-seismic tsunamis: filling the forecast gap

    Science.gov (United States)

    Moore, C. W.; Titov, V. V.; Spillane, M. C.

    2015-12-01

    Earthquakes are the generation mechanism in over 85% of tsunamis. However, non-seismic tsunamis, including those generated by meteorological events, landslides, volcanoes, and asteroid impacts, can inundate significant area and have a large far-field effect. The current National Oceanographic and Atmospheric Administration (NOAA) tsunami forecast system falls short in detecting these phenomena. This study attempts to classify the range of effects possible from these non-seismic threats, and to investigate detection methods appropriate for use in a forecast system. Typical observation platforms are assessed, including DART bottom pressure recorders and tide gauges. Other detection paths include atmospheric pressure anomaly algorithms for detecting meteotsunamis and the early identification of asteroids large enough to produce a regional hazard. Real-time assessment of observations for forecast use can provide guidance to mitigate the effects of a non-seismic tsunami.

  2. Calculation of Tsunami Damage and preparation of Inundation Maps by 2D and 3D numerical modeling in Göcek, Turkey

    Science.gov (United States)

    Ozer Sozdinler, C.; Arikawa, T.; Necmioglu, O.; Ozel, N. M.

    2016-12-01

    The Aegean and its surroundings form the most active part of the Africa-Eurasia collision zone responsible for the high level of seismicity in this region. It constitutes more than 60% of the expected seismicity in Europe up to Mw=8.2 (Moratto et al., 2007; Papazachos, 1990). Shaw and Jackson (2010) argued that the existing system of Hellenic Arc subduction-zone is capable of allowing very large but rare earthquakes on splay faults, such as the one occurred in 365, together with the contribution of small earthquakes. Based on an extensive earthquake generated tsunami scenario database, Necmioğlu and Özel (2015) showed that maximum wave heights in the Eastern Mediterranean for shallow earthquakes defined is >3 m in locations in, around and orthogonal to the Hellenic Arc. Considering the seismicity and the tsunami potential in Eastern Mediterranean, the investigation and monitoring of earthquake and tsunami hazard, and the preparation of mitigation strategies and national resilience plans would become inevitable in Turkey. Gocek town, as one of the Tsunami Forecast Points having a unique geography with many small bays and islands and a very popular touristic destination especially for yachtsmen, is selected in this study for the tsunami modeling by using high resolution bathymetric and topographic data with less than 4m grid size. The tsunami analyses are performed by the numerical codes NAMIDANCE (NAMIDANCE,2011) for 2D modeling and STOC-CADMAS (Arikawa,2014) for 3D modeling for the calculations of tsunami hydrodynamic parameters. Froude numbers, as one of the most important indicators for tsunami damage (Ozer, 2012) and the directions of current velocities inside marinas are solved by NAMIDANCE while STOC-CADMAS determines the tsunami pressure and force exerted onto the sea and land structures with 3D and non-hydrostatic approaches. The results are then used to determine the tsunami inundation and structural resilience and establish the tsunami preparedness and

  3. Crowdsourced earthquake early warning

    Science.gov (United States)

    Minson, Sarah E.; Brooks, Benjamin A.; Glennie, Craig L.; Murray, Jessica R.; Langbein, John O.; Owen, Susan E.; Heaton, Thomas H.; Iannucci, Robert A.; Hauser, Darren L.

    2015-01-01

    Earthquake early warning (EEW) can reduce harm to people and infrastructure from earthquakes and tsunamis, but it has not been implemented in most high earthquake-risk regions because of prohibitive cost. Common consumer devices such as smartphones contain low-cost versions of the sensors used in EEW. Although less accurate than scientific-grade instruments, these sensors are globally ubiquitous. Through controlled tests of consumer devices, simulation of an Mw (moment magnitude) 7 earthquake on California’s Hayward fault, and real data from the Mw 9 Tohoku-oki earthquake, we demonstrate that EEW could be achieved via crowdsourcing.

  4. Geological and historical evidence of irregular recurrent earthquakes in Japan.

    Science.gov (United States)

    Satake, Kenji

    2015-10-28

    Great (M∼8) earthquakes repeatedly occur along the subduction zones around Japan and cause fault slip of a few to several metres releasing strains accumulated from decades to centuries of plate motions. Assuming a simple 'characteristic earthquake' model that similar earthquakes repeat at regular intervals, probabilities of future earthquake occurrence have been calculated by a government committee. However, recent studies on past earthquakes including geological traces from giant (M∼9) earthquakes indicate a variety of size and recurrence interval of interplate earthquakes. Along the Kuril Trench off Hokkaido, limited historical records indicate that average recurrence interval of great earthquakes is approximately 100 years, but the tsunami deposits show that giant earthquakes occurred at a much longer interval of approximately 400 years. Along the Japan Trench off northern Honshu, recurrence of giant earthquakes similar to the 2011 Tohoku earthquake with an interval of approximately 600 years is inferred from historical records and tsunami deposits. Along the Sagami Trough near Tokyo, two types of Kanto earthquakes with recurrence interval of a few hundred years and a few thousand years had been recognized, but studies show that the recent three Kanto earthquakes had different source extents. Along the Nankai Trough off western Japan, recurrence of great earthquakes with an interval of approximately 100 years has been identified from historical literature, but tsunami deposits indicate that the sizes of the recurrent earthquakes are variable. Such variability makes it difficult to apply a simple 'characteristic earthquake' model for the long-term forecast, and several attempts such as use of geological data for the evaluation of future earthquake probabilities or the estimation of maximum earthquake size in each subduction zone are being conducted by government committees. © 2015 The Author(s).

  5. Tsunamigenic earthquakes in the Gulf of Cadiz: fault model and recurrence

    Directory of Open Access Journals (Sweden)

    L. M. Matias

    2013-01-01

    Full Text Available The Gulf of Cadiz, as part of the Azores-Gibraltar plate boundary, is recognized as a potential source of big earthquakes and tsunamis that may affect the bordering countries, as occurred on 1 November 1755. Preparing for the future, Portugal is establishing a national tsunami warning system in which the threat caused by any large-magnitude earthquake in the area is estimated from a comprehensive database of scenarios. In this paper we summarize the knowledge about the active tectonics in the Gulf of Cadiz and integrate the available seismological information in order to propose the generation model of destructive tsunamis to be applied in tsunami warnings. The fault model derived is then used to estimate the recurrence of large earthquakes using the fault slip rates obtained by Cunha et al. (2012 from thin-sheet neotectonic modelling. Finally we evaluate the consistency of seismicity rates derived from historical and instrumental catalogues with the convergence rates between Eurasia and Nubia given by plate kinematic models.

  6. The Global Tsunami Model (GTM)

    Science.gov (United States)

    Lorito, S.; Basili, R.; Harbitz, C. B.; Løvholt, F.; Polet, J.; Thio, H. K.

    2017-12-01

    The tsunamis occurred worldwide in the last two decades have highlighted the need for a thorough understanding of the risk posed by relatively infrequent but often disastrous tsunamis and the importance of a comprehensive and consistent methodology for quantifying the hazard. In the last few years, several methods for probabilistic tsunami hazard analysis have been developed and applied to different parts of the world. In an effort to coordinate and streamline these activities and make progress towards implementing the Sendai Framework of Disaster Risk Reduction (SFDRR) we have initiated a Global Tsunami Model (GTM) working group with the aim of i) enhancing our understanding of tsunami hazard and risk on a global scale and developing standards and guidelines for it, ii) providing a portfolio of validated tools for probabilistic tsunami hazard and risk assessment at a range of scales, and iii) developing a global tsunami hazard reference model. This GTM initiative has grown out of the tsunami component of the Global Assessment of Risk (GAR15), which has resulted in an initial global model of probabilistic tsunami hazard and risk. Started as an informal gathering of scientists interested in advancing tsunami hazard analysis, the GTM is currently in the process of being formalized through letters of interest from participating institutions. The initiative has now been endorsed by the United Nations International Strategy for Disaster Reduction (UNISDR) and the World Bank's Global Facility for Disaster Reduction and Recovery (GFDRR). We will provide an update on the state of the project and the overall technical framework, and discuss the technical issues that are currently being addressed, including earthquake source recurrence models, the use of aleatory variability and epistemic uncertainty, and preliminary results for a probabilistic global hazard assessment, which is an update of the model included in UNISDR GAR15.

  7. Process, practice and priorities — key lessons learnt undertaking sensitive social reconnaissance research as part of an (UNESCO-IOC) International Tsunami Survey Team

    Science.gov (United States)

    van Zijll de Jong, Shona L.; Dominey-Howes, Dale; Roman, Carolina E.; Calgaro, Emma; Gero, Anna; Veland, Siri; Bird, Deanne K.; Muliaina, Tolu; Tuiloma-Sua, Dawn; Afioga, Taulagi Latu

    2011-07-01

    The 29 September 2009 South Pacific tsunami has had a lasting impact upon local coastal villages and global collaborative research efforts. Locally, the impact of the tsunami is one of the most severe disasters Samoa has experienced in the last several decades. Within one week of the event, 143 people died. Approximately 6000 traumatized men, women and children - terrified of the sea - refused to return to live or work in their rural, coastal villages, which in turn has had broad consequences for humanitarian emergency relief distribution networks and early recovery planning efforts. Researchers came from all over the world to participate in the UNESCO International Oceanographic Commission (IOC) Samoa International Tsunami Survey Team (ITST). Focusing on the need for interdisciplinary research, for the first time, a social impact assessment team (SIT) was expressly invited to participate. Within days of the tsunami, a group of Australian, New Zealand, American, Fijian, and Japanese disaster researchers began to discuss how they might develop a social science reconnaissance research plan using innovative approaches and best practice. This paper presents an overview of challenges faced by the social impact assessment team with a focus on lessons to be learnt from this experience. We discuss the need to clarify project boundaries, develop a core research agenda and project milestones, and develop day-to-day fieldwork work plans and at the same time be sensitive to the emotional needs of the interviewees as well as the researchers. We also make several practical suggestions for future social reconnaissance research with a set of recommendations to support disaster researchers as they plan their own research projects. The inclusion of a social impacts assessment group within a UNESCO-IOC ITST was a valuable response to the increasing need for responsible social research in sensitive topics of post-disaster analysis. Social scientists are aware that disaster social

  8. The quest for wisdom: lessons from 17 tsunamis, 2004-2014.

    Science.gov (United States)

    Okal, Emile A

    2015-10-28

    Since the catastrophic Sumatra-Andaman tsunami took place in 2004, 16 other tsunamis have resulted in significant damage and 14 in casualties. We review the fundamental changes that have affected our command of tsunami issues as scientists, engineers and decision-makers, in the quest for improved wisdom in this respect. While several scientific paradigms have had to be altered or abandoned, new algorithms, e.g. the W seismic phase and real-time processing of fast-arriving seismic P waves, give us more powerful tools to estimate in real time the tsunamigenic character of an earthquake. We assign to each event a 'wisdom index' based on the warning issued (or not) during the event, and on the response of the population. While this approach is admittedly subjective, it clearly shows several robust trends: (i) we have made significant progress in our command of far-field warning, with only three casualties in the past 10 years; (ii) self-evacuation by educated populations in the near field is a key element of successful tsunami mitigation; (iii) there remains a significant cacophony between the scientific community and decision-makers in industry and government as documented during the 2010 Maule and 2011 Tohoku events; and (iv) the so-called 'tsunami earthquakes' generating larger tsunamis than expected from the size of their seismic source persist as a fundamental challenge, despite scientific progress towards characterizing these events in real time. © 2015 The Author(s).

  9. Advances in coastal disasters risk management : Lessons from the 2011 Tohoku tsunami

    NARCIS (Netherlands)

    Jonkman, S.N.; Yasuda, T.; Tsimopoulou, V.; Kawai, H.; Kato, F.

    2012-01-01

    The earthquake and tsunami of March 2011 led to death and destruction in coastal areas in Japan. A seminar was held in June 2012 for Japanese and Dutch coastal researchers to discuss lessons for the management of the risks in coastal areas associated with tsunamis, typhoons and storm surges. The

  10. New method to determine initial surface water displacement at tsunami source

    Science.gov (United States)

    Lavrentyev, Mikhail; Romanenko, Alexey; Tatarintsev, Pavel

    2013-04-01

    Friday, March 11, 2011 at 05:46:23 UTC, Japan was struck by an 8.9-magnitude earthquake near its Northeastern coast. This is one of the largest earthquakes that Japan has ever experienced. Tsunami waves swept away houses and cars and caused massive human losses. To predict tsunami wave parameters better and faster, we propose to improve data inversion scheme and achieve the performance gain of data processing. One of the reasons of inaccurate predictions of tsunami parameters is that very little information is available about the initial disturbance of the sea bed at tsunami source. In this paper, we suggest a new way of improving the quality of tsunami source parameters prediction. Modern computational technologies can accurately calculate tsunami wave propagation over the deep ocean provided that the initial displacement (perturbation of the sea bed at tsunami source) is known [4]. Direct geophysical measurements provide the location of an earthquake hypocenter and its magnitude (the released energy evaluation). Among the methods of determination of initial displacement the following ones should be considered. Calculation through the known fault structure and available seismic information. This method is widely used and provides useful information. However, even if the exact knowledge about rock blocks shifts is given, recalculation in terms of sea bed displacement is needed. This results in a certain number of errors. GPS data analysis. This method was developed after the December 2004 event in the Indian Ocean. A good correlation between dry land based GPS sensors and tsunami wave parameters was observed in the particular case of the West coast of Sumatra, Indonesia. This approach is very unique and can hardly been used in other geo locations. Satellite image analysis. The resolution of modern satellite images has dramatically improved. In the future, correct data of sea surface displacement will probably be available in real time, right after a tsunamigenic

  11. A contribution to the selection of tsunami human vulnerability indicators: conclusions from tsunami impacts in Sri Lanka and Thailand (2004), Samoa (2009), Chile (2010) and Japan (2011)

    Science.gov (United States)

    González-Riancho, P.; Aliaga, B.; Hettiarachchi, S.; González, M.; Medina, R.

    2015-07-01

    After several tsunami events with disastrous consequences around the world, coastal countries have realized the need to be prepared to minimize human mortality and damage to coastal infrastructures, livelihoods and resources. The international scientific community is striving to develop and validate methodologies for tsunami hazard and vulnerability and risk assessments. The vulnerability of coastal communities is usually assessed through the definition of sets of indicators based on previous literature and/or post-tsunami reports, as well as on the available data for the study site. The aim of this work is to validate, in light of past tsunami events, the indicators currently proposed by the scientific community to measure human vulnerability, to improve their definition and selection as well as to analyse their validity for different country development profiles. The events analysed are the 2011 Great Tohoku tsunami, the 2010 Chilean tsunami, the 2009 Samoan tsunami and the 2004 Indian Ocean tsunami. The results obtained highlight the need for considering both permanent and temporal human exposure, the former requiring some hazard numerical modelling, while the latter is related to site-specific livelihoods, cultural traditions and gender roles. The most vulnerable age groups are the elderly and children, the former having much higher mortality rates. Female mortality is not always higher than male mortality and not always related to dependency issues. Higher numbers of disabled people do not always translate into higher numbers of victims. Besides, it is clear that mortality is not only related to the characteristics of the population but also of the buildings. A high correlation has been found between the affected buildings and the number of victims, being very high for completely damaged buildings. Distance to the sea, building materials and expected water depths are important determining factors regarding the type of damage to buildings.

  12. Elders recall an earlier tsunami on Indian Ocean shores

    Science.gov (United States)

    Kakar, Din Mohammad; Naeem, Ghazala; Usman, Abdullah; Hasan, Haider; Lohdi, Hira; Srinivasalu, Seshachalam; Andrade, Vanessa; Rajendran, C.P.; Naderi Beni, Abdolmajid; Hamzeh, Mohammad Ali; Hoffmann, Goesta; Al Balushi, Noora; Gale, Nora; Kodijat, Ardito; Fritz, Hermann M.; Atwater, Brian F.

    2014-01-01

    Ten years on, the Indian Ocean tsunami of 26 December 2004 still looms large in efforts to reduce coastal risk. The disaster has spurred worldwide advances in tsunami detection and warning, tsunami-risk assessment, and tsunami awareness [Satake, 2014]. Nearly a lifetime has passed since the northwestern Indian Ocean last produced a devastating tsunami. Documentation of this tsunami, in November 1945, was hindered by international instability in the wake of the Second World War and, in British India, by the approach of independence and partition. The parent earthquake, of magnitude 8.1, was widely recorded, and the tsunami registered on tide gauges, but intelligence reports and newspaper articles say little about inundation limits while permitting a broad range of catalogued death tolls. What has been established about the 1945 tsunami falls short of what's needed today for ground-truthing inundation models, estimating risk to enlarged populations, and anchoring awareness campaigns in local facts. Recent efforts to reduce coastal risk around the Arabian Sea include a project in which eyewitnesses to the 1945 tsunami were found and interviewed (Fig. 1), and related archives were gathered. Results are being made available through UNESCO's Indian Ocean Tsunami Information Center in hopes of increasing scientific understanding and public awareness of the region's tsunami hazards.

  13. Tsunami excitation by inland/coastal earthquakes: the Green function approach

    Directory of Open Access Journals (Sweden)

    T. B. Yanovskaya

    2003-01-01

    Full Text Available In the framework of the linear theory, the representation theorem is derived for an incompressible liquid layer with a boundary of arbitrary shape and in a homogeneous gravity field. In addition, the asymptotic representation for the Green function, in a layer of constant thickness is obtained. The validity of the approach for the calculation of the tsunami wavefield based on the Green function technique is verified comparing the results with those obtained from the modal theory, for a liquid layer of infinite horizontal dimensions. The Green function approach is preferable for the estimation of the excitation spectra, since in the case of an infinite liquid layer it leads to simple analytical expressions. From this analysis it is easy to describe the peculiarities of tsunami excitation by different sources. The method is extended to the excitation of tsunami in a semiinfinite layer with a sloping boundary. Numerical modelling of the tsunami wavefield, excited by point sources at different distances from the coastline, shows that when the source is located at a distance from the coastline equal or larger than the source depth, the shore presence does not affect the excitation of the tsunami. When the source is moved towards thecoastline, the low frequency content in the excitation spectrum ecreases, while the high frequencies content increases dramatically. The maximum of the excitation spectra from inland sources, located at a distance from the shore like the source depth, becomes less than 10% of that radiated if the same source is located in the open ocean. The effect of the finiteness of the source is also studied and the excitation spectrum is obtained by integration over the fault area. Numerical modelling of the excitation spectra for different source models shows that, for a given seismic moment, the spectral level, as well as the maximum value of the spectra, decreases with increasing fault size. When the sources are located in the

  14. Historical and paleo-tsunami deposits on Kamchatka, Russia: long-term chronologies and long-distance correlations

    Directory of Open Access Journals (Sweden)

    T. K. Pinegina

    2001-01-01

    Full Text Available Along the eastern coast of Kamchatka, at a number of localities, we have identified and attempted to assign ages to deposits of both historic and prehistoric (paleo- tsunamis. These deposits are dated and correlated using tephrochronology from Holocene marker tephra and local volcanic ash layers. Because the historical record of earthquakes and tsunamis on Kamchatka is so short, these investigations can make important contributions to evaluating tsunami hazards. Moreover, because even the historical record is spotty, our work helps add to and evaluate tsunami catalogues for Kamchatka. Furthermore, tsunami deposits provide a proxy record for large earthquakes and thus are important paleoseismological tools. The combined, preserved record of tsunami deposits and of numerous marker tephra on Kamchatka offers an unprecedented opportunity to study tsunami frequency. Using combined stratigraphic sections, we can examine both the average frequency of events for each locality, and also changes in frequency through time. Moreover, using key marker tephra as time lines, we can compare tsunami frequency and intensity records along the Kamchatka subduction zone. Preliminary results suggest real variations in frequency on a millennial time scale, with the period from about 0 to 1000 A.D. being particularly active at some localities.

  15. The Moneron Tsunami of September 5, 1971, and Its Manifestation on the Sakhalin Island Coast: Numerical Simulation Results

    Science.gov (United States)

    Kostenko, I. S.; Zaytsev, A. I.; Minaev, D. D.; Kurkin, A. A.; Pelinovsky, E. N.; Oshmarina, O. E.

    2018-01-01

    Observation data on the September 5, 1971, earthquake that occurred near the Moneron Island (Sakhalin) have been analyzed and a numerical simulation of the tsunami induced by this earthquake is conducted. The tsunami source identified in this study indicates that the observational data are in good agreement with the results of calculations performed on the basis of shallow-water equations.

  16. Challenges in Defining Tsunami Wave Height

    Science.gov (United States)

    Stroker, K. J.; Dunbar, P. K.; Mungov, G.; Sweeney, A.; Arcos, N. P.

    2017-12-01

    The NOAA National Centers for Environmental Information (NCEI) and co-located World Data Service for Geophysics maintain the global tsunami archive consisting of the historical tsunami database, imagery, and raw and processed water level data. The historical tsunami database incorporates, where available, maximum wave heights for each coastal tide gauge and deep-ocean buoy that recorded a tsunami signal. These data are important because they are used for tsunami hazard assessment, model calibration, validation, and forecast and warning. There have been ongoing discussions in the tsunami community about the correct way to measure and report these wave heights. It is important to understand how these measurements might vary depending on how the data were processed and the definition of maximum wave height. On September 16, 2015, an 8.3 Mw earthquake located 48 km west of Illapel, Chile generated a tsunami that was observed all over the Pacific region. We processed the time-series water level data for 57 tide gauges that recorded this tsunami and compared the maximum wave heights determined from different definitions. We also compared the maximum wave heights from the NCEI-processed data with the heights reported by the NOAA Tsunami Warning Centers. We found that in the near field different methods of determining the maximum tsunami wave heights could result in large differences due to possible instrumental clipping. We also found that the maximum peak is usually larger than the maximum amplitude (½ peak-to-trough), but the differences for the majority of the stations were Warning Centers. Since there is currently only one field in the NCEI historical tsunami database to store the maximum tsunami wave height, NCEI will consider adding an additional field for the maximum peak measurement.

  17. REWSET: A prototype seismic and tsunami early warning system in Rhodes island, Greece

    Science.gov (United States)

    Papadopoulos, Gerasimos; Argyris, Ilias; Aggelou, Savvas; Karastathis, Vasilis

    2014-05-01

    Tsunami warning in near-field conditions is a critical issue in the Mediterranean Sea since the most important tsunami sources are situated within tsunami wave travel times starting from about five minutes. The project NEARTOWARN (2012-2013) supported by the EU-DG ECHO contributed substantially to the development of new tools for the near-field tsunami early warning in the Mediterranean. One of the main achievements is the development of a local warning system in the test-site of Rhodes island (Rhodes Early Warning System for Earthquakes and Tsunamis - REWSET). The system is composed by three main subsystems: (1) a network of eight seismic early warning devices installed in four different localities of the island, one in the civil protection, another in the Fire Brigade and another two in municipality buildings; (2) two radar-type (ultrasonic) tide-gauges installed in the eastern coastal zine of the island which was selected since research on the historical earthquake and tsunami activity has indicated that the most important, near-field tsunami sources are situated offshore to the east of Rhodes; (3) a crisis Geographic Management System (GMS), which is a web-based and GIS-based application incorporating a variety of thematic maps and other information types. The seismic early warning devices activate by strong (magnitude around 6 or more) earthquakes occurring at distances up to about 100 km from Rhodes, thus providing immediate mobilization of the civil protection. The tide-gauges transmit sea level data, while during the crisis the GMS supports decisions to be made by civil protection. In the near future it is planned the REWSET system to be integrated with national and international systems. REWSET is a prototype which certainly could be developed in other coastal areas of the Mediterranean and beyond.

  18. Educating and Preparing for Tsunamis in the Caribbean

    Science.gov (United States)

    von Hillebrandt-Andrade, C.; Aliaga, B.; Edwards, S.

    2013-12-01

    The Caribbean and Adjacent Regions has a long history of tsunamis and earthquakes. Over the past 500 years, more than 75 tsunamis have been documented in the region by the NOAA National Geophysical Data Center. Just since 1842, 3446 lives have been lost to tsunamis; this is more than in the Northeastern Pacific for the same time period. With a population of almost 160 million, over 40 million visitors a year and a heavy concentration of residents, tourists, businesses and critical infrastructure along its shores (especially in the northern and eastern Caribbean), the risk to lives and livelihoods is greater than ever before. The only way to survive a tsunami is to get out of harm's way before the waves strike. In the Caribbean given the relatively short distances from faults, potential submarine landslides and volcanoes to some of the coastlines, the tsunamis are likely to be short fused, so it is imperative that tsunami warnings be issued extremely quickly and people be educated on how to recognize and respond. Nevertheless, given that tsunamis occur infrequently as compared with hurricanes, it is a challenge for them to receive the priority they require in order to save lives when the next one strikes the region. Close cooperation among countries and territories is required for warning, but also for education and public awareness. Geographical vicinity and spoken languages need to be factored in when developing tsunami preparedness in the Caribbean, to make sure citizens receive a clear, reliable and sound science based message about the hazard and the risk. In 2006, in the wake of the Indian Ocean tsunami and after advocating without success for a Caribbean Tsunami Warning System since the mid 90's, the Intergovernmental Oceanographic Commission of UNESCO established the Intergovernmental Coordination Group for the Tsunami and other Coastal Hazards Warning System for the Caribbean and Adjacent Regions (CARIBE EWS). Its purpose is to advance an end to end tsunami

  19. Numerical reconstruction of tsunami source using combined seismic, satellite and DART data

    Science.gov (United States)

    Krivorotko, Olga; Kabanikhin, Sergey; Marinin, Igor

    2014-05-01

    function, the adjoint problem is solved. The conservative finite-difference schemes for solving the direct and adjoint problems in the approximation of shallow water are constructed. Results of numerical experiments of the tsunami source reconstruction are presented and discussed. We show that using a combination of three different types of data allows one to increase the stability and efficiency of tsunami source reconstruction. Non-profit organization WAPMERR (World Agency of Planetary Monitoring and Earthquake Risk Reduction) in collaboration with Informap software development department developed the Integrated Tsunami Research and Information System (ITRIS) to simulate tsunami waves and earthquakes, river course changes, coastal zone floods, and risk estimates for coastal constructions at wave run-ups and earthquakes. The special scientific plug-in components are embedded in a specially developed GIS-type graphic shell for easy data retrieval, visualization and processing. This work was supported by the Russian Foundation for Basic Research (project No. 12-01-00773 'Theory and Numerical Methods for Solving Combined Inverse Problems of Mathematical Physics') and interdisciplinary project of SB RAS 14 'Inverse Problems and Applications: Theory, Algorithms, Software'.

  20. Prevalence and risk factors for depressive reaction among resident survivors after the tsunami following the Great East Japan Earthquake, March 11, 2011.

    Directory of Open Access Journals (Sweden)

    Chieko Matsubara

    Full Text Available The Great East Japan Earthquake caused a gigantic tsunami which devastated coastal areas of northern Japan on 11 March 2011. Despite the large number of 'resident survivors' who continued to reside in their damaged houses on the second or upper floors, research on the mental health of these individuals has been limited. This study explored the prevalence of depressive reaction and risk factors for depressive reaction among these resident survivors.A cross-sectional household health support needs screening was conducted for resident survivors in Higashi-Matsushima city, Miyagi prefecture, two to four months after the tsunami. The health interview that was conducted including mental status, assessed by the Patient Health Questionnaire-2 (PHQ-2.Of 5,454 respondents, 8.1% had depressive reaction. After adjustment by the number of weeks from the tsunami and the mortality rate at each respondent's place of residence, depressive reaction was significantly associated with house flooding below or above the ground floor (odds ratios of 1.92, 2.36, respectively, the unavailability of gas supply (odds ratio, 1.67, being female (odds ratio, 1.47, middle aged or elderly (odds ratios of 2.41, 2.42, respectively, regular intake of psychotropic medicine(s since before the tsunami (odds ratio, 2.53 and the presence of one to five or more than six cohabiters (odds ratios of 0.61, 0.52, respectively.The results suggest a considerable psychological burden (depressive reaction following the tsunami among resident survivors. Special supports for families with psychiatric problems need to be considered among resident survivors. Restoration of lifeline utilities and the strengthening of social ties of persons living alone may help prevent depressive reaction among resident survivors after a tsunami.

  1. Prevalence and risk factors for depressive reaction among resident survivors after the tsunami following the Great East Japan Earthquake, March 11, 2011.

    Science.gov (United States)

    Matsubara, Chieko; Murakami, Hitoshi; Imai, Koubun; Mizoue, Tetsuya; Akashi, Hidechika; Miyoshi, Chiaki; Nakasa, Tamotsu

    2014-01-01

    The Great East Japan Earthquake caused a gigantic tsunami which devastated coastal areas of northern Japan on 11 March 2011. Despite the large number of 'resident survivors' who continued to reside in their damaged houses on the second or upper floors, research on the mental health of these individuals has been limited. This study explored the prevalence of depressive reaction and risk factors for depressive reaction among these resident survivors. A cross-sectional household health support needs screening was conducted for resident survivors in Higashi-Matsushima city, Miyagi prefecture, two to four months after the tsunami. The health interview that was conducted including mental status, assessed by the Patient Health Questionnaire-2 (PHQ-2). Of 5,454 respondents, 8.1% had depressive reaction. After adjustment by the number of weeks from the tsunami and the mortality rate at each respondent's place of residence, depressive reaction was significantly associated with house flooding below or above the ground floor (odds ratios of 1.92, 2.36, respectively), the unavailability of gas supply (odds ratio, 1.67), being female (odds ratio, 1.47), middle aged or elderly (odds ratios of 2.41, 2.42, respectively), regular intake of psychotropic medicine(s) since before the tsunami (odds ratio, 2.53) and the presence of one to five or more than six cohabiters (odds ratios of 0.61, 0.52, respectively). The results suggest a considerable psychological burden (depressive reaction) following the tsunami among resident survivors. Special supports for families with psychiatric problems need to be considered among resident survivors. Restoration of lifeline utilities and the strengthening of social ties of persons living alone may help prevent depressive reaction among resident survivors after a tsunami.

  2. Database of tsunami scenario simulations for Western Iberia: a tool for the TRIDEC Project Decision Support System for tsunami early warning

    Science.gov (United States)

    Armigliato, Alberto; Pagnoni, Gianluca; Zaniboni, Filippo; Tinti, Stefano

    2013-04-01

    TRIDEC is a EU-FP7 Project whose main goal is, in general terms, to develop suitable strategies for the management of crises possibly arising in the Earth management field. The general paradigms adopted by TRIDEC to develop those strategies include intelligent information management, the capability of managing dynamically increasing volumes and dimensionality of information in complex events, and collaborative decision making in systems that are typically very loosely coupled. The two areas where TRIDEC applies and tests its strategies are tsunami early warning and industrial subsurface development. In the field of tsunami early warning, TRIDEC aims at developing a Decision Support System (DSS) that integrates 1) a set of seismic, geodetic and marine sensors devoted to the detection and characterisation of possible tsunamigenic sources and to monitoring the time and space evolution of the generated tsunami, 2) large-volume databases of pre-computed numerical tsunami scenarios, 3) a proper overall system architecture. Two test areas are dealt with in TRIDEC: the western Iberian margin and the eastern Mediterranean. In this study, we focus on the western Iberian margin with special emphasis on the Portuguese coasts. The strategy adopted in TRIDEC plans to populate two different databases, called "Virtual Scenario Database" (VSDB) and "Matching Scenario Database" (MSDB), both of which deal only with earthquake-generated tsunamis. In the VSDB we simulate numerically few large-magnitude events generated by the major known tectonic structures in the study area. Heterogeneous slip distributions on the earthquake faults are introduced to simulate events as "realistically" as possible. The members of the VSDB represent the unknowns that the TRIDEC platform must be able to recognise and match during the early crisis management phase. On the other hand, the MSDB contains a very large number (order of thousands) of tsunami simulations performed starting from many different

  3. Multi-GPGPU Tsunami simulation at Toyama-bay

    Science.gov (United States)

    Furuyama, Shoichi; Ueda, Yuki

    2017-07-01

    Accelerated multi General Purpose Graphics Processing Unit (GPGPU) calculation for Tsunami run-up simulation was achieved at the wide area (whole Toyama-bay in Japan) by faster computation technique. Toyama-bay has active-faults at the sea-bed. It has a high possibility to occur earthquakes and Tsunami waves in the case of the huge earthquake, that's why to predict the area of Tsunami run-up is important for decreasing damages to residents by the disaster. However it is very hard task to achieve the simulation by the computer resources problem. A several meter's order of the high resolution calculation is required for the running-up Tsunami simulation because artificial structures on the ground such as roads, buildings, and houses are very small. On the other hand the huge area simulation is also required. In the Toyama-bay case the area is 42 [km] × 15 [km]. When 5 [m] × 5 [m] size computational cells are used for the simulation, over 26,000,000 computational cells are generated. To calculate the simulation, a normal CPU desktop computer took about 10 hours for the calculation. An improvement of calculation time is important problem for the immediate prediction system of Tsunami running-up, as a result it will contribute to protect a lot of residents around the coastal region. The study tried to decrease this calculation time by using multi GPGPU system which is equipped with six NVIDIA TESLA K20xs, InfiniBand network connection between computer nodes by MVAPICH library. As a result 5.16 times faster calculation was achieved on six GPUs than one GPU case and it was 86% parallel efficiency to the linear speed up.

  4. Geothermal energy for American Samoa

    Energy Technology Data Exchange (ETDEWEB)

    1980-03-01

    The geothermal commercialization potential in American Samoa was investigated. With geothermal energy harnessed in American Samoa, a myriad of possibilities would arise. Existing residential and business consumers would benefit from reduced electricity costs. The tuna canneries, demanding about 76% of the island's process heat requirements, may be able to use process heat from a geothermal source. Potential new industries include health spas, aquaculture, wood products, large domestic and transhipment refrigerated warehouses, electric cars, ocean nodule processing, and a hydrogen economy. There are no territorial statutory laws of American Samoa claiming or reserving any special rights (including mineral rights) to the territorial government, or other interests adverse to a land owner, for subsurface content of real property. Technically, an investigation has revealed that American Samoa does possess a geological environment conducive to geothermal energy development. Further studies and test holes are warranted.

  5. Development of an Android App for notification and reporting of natural disaster such as earthquakes and tsunamis

    Science.gov (United States)

    Richter, Steffen; Hammitzsch, Martin

    2013-04-01

    Disasters like the Tohoku tsunami in March 2011 and the earthquake in Haiti in January 2010, have shown clearly that the rapid detection of possible negative impact on population and infrastructure is crucial for the rapid organization of effective counter measures integration activities. It has turned out that effective planning of relief and rescue measures requires both information provided by governmental authorities and feedback of the general public. Every citizen experiencing the events directly on site becomes a potential witness and can provide valuable information about the disaster. Citizens can use various information channels to communicate and share their experiences. During the last years, the crowdsourcing approach has gained the attention of users of modern communication and information systems. The term crowdsourcing describes the interactive collaboration of voluntary users on the Internet, working on a common topic. A similar approach is mobile crowdsourcing which evolved in the quickly growing community of smartphone users: Crowdsourcing platforms provide additional application scenarios for modern smartphone. Smartphone users are enabled to compose and share reports immediately at the scene of the disaster. A growing number of modern smartphones also includes sensors for taking pictures and to determine the current geographical position. This additional content can significantly enhance the value of a disaster event report. The project Collaborative, Complex, and Critical Decision-Support in Evolving Crises (TRIDEC), co-funded by the European Commission in its Seventh Framework Programme, is focused on the management of crisis situations. Part of the project is the development of an application for the Android smartphone platform. This application enables access to an continuously updated situation report for current natural disasters like earthquakes and tsunamis based on incoming crowdsourced reports. The App is used to immediately sent

  6. Paleo-tsunami history along the northern Japan Trench: evidence from Noda Village, northern Sanriku coast, Japan

    Science.gov (United States)

    Inoue, Taiga; Goto, Kazuhisa; Nishimura, Yuichi; Watanabe, Masashi; Iijima, Yasutaka; Sugawara, Daisuke

    2017-12-01

    Throughout history, large tsunamis have frequently affected the Sanriku area of the Pacific coast of the Tohoku region, Japan, which faces the Japan Trench. Although a few studies have examined paleo-tsunami deposits along the Sanriku coast, additional studies of paleo-earthquakes and tsunamis are needed to improve our knowledge of the timing, recurrence interval, and size of historical and pre-historic tsunamis. At Noda Village, in Iwate Prefecture on the northern Sanriku coast, we found at least four distinct gravelly sand layers based on correlation and chronological data. Sedimentary features such as grain size and thickness suggest that extreme waves from the sea formed these layers. Numerical modeling of storm waves further confirmed that even extremely large storm waves cannot account for the distribution of the gravelly sand layers, suggesting that these deposits are highly likely to have formed by tsunami waves. The numerical method of storm waves can be useful to identify sand layers as tsunami deposits if the deposits are observed far inland or at high elevations. The depositional age of the youngest tsunami deposit is consistent with the AD 869 Jogan earthquake tsunami, a possible predecessor of the AD 2011 Tohoku-oki tsunami. If this is the case, then the study site currently defines the possible northern extent of the AD 869 Jogan tsunami deposit, which is an important step in improving the tsunami source model of the AD 869 Jogan tsunami. Our results suggest that four large tsunamis struck the Noda site between 1100 and 2700 cal BP. The local tsunami sizes are comparable to the AD 2011 and AD 1896 Meiji Sanriku tsunamis, considering the landward extent of each tsunami deposit.

  7. The Tsunami Project: Integrating engineering, natural and social sciences into post-tsunami surveys

    Science.gov (United States)

    McAdoo, B. G.; Goff, J. R.; Fritz, H. M.; Cochard, R.; Kong, L. S.

    2009-12-01

    Complexities resulting from recent tsunamis in the Solomon Islands (2007), Java (2006) and Sumatra (2004, 2005) have demonstrated the need for an integrated, interdisciplinary team of engineers, natural and social scientists to better understand the nature of the disaster. Documenting the complex interactions in the coupled human-environment system necessitate a coordinated, interdisciplinary approach that combines the strengths of engineering, geoscience, ecology and social science. Engineers, modelers and geoscientists untangle the forces required to leave an imprint of a tsunami in the geologic record. These same forces affect ecosystems that provide services from buffers to food security; therefore coastal ecologists play a vital role. It is also crucial to understand the social structures that contribute to disasters, so local or regional policy experts, planners, economists, etc. should be included. When these experts arrive in a disaster area as part of an Interdisciplinary Tsunami Survey Team, the interactions between the systems can be discussed in the field, and site-specific data can be collected. A diverse team in the field following a tsunami shares critical resources and discoveries in real-time, making the survey more efficient. Following the 2006 Central Java earthquake and tsunami, civil engineers covered broad areas quickly, collecting ephemeral water level data and communicating areas of interest to the geologists, who would follow to do the slower sediment data collection. The 2007 Solomon Islands earthquake and tsunami caused extensive damage to the coral reef, which highlighting the need to have an ecologist on the team who was able to identify species and their energy tolerance. Rather than diluting the quality of post-tsunami data collection, this approach in fact strengthens it- engineers and geoscientists no longer have to indentify coral or mangrove species, nor do ecologists evaluate the velocity of a wave as it impacted a forested

  8. Investigation on tsunami effects in the central Adriatic Sea during the last century – a contribution

    Directory of Open Access Journals (Sweden)

    A. Maramai

    2007-01-01

    Full Text Available In this work we present the result of a study aimed at examining the Italian earthquake sequences that occurred in the area of the central Adriatic sea with the purpose of understanding whether some of them were accompanied by tsunami effects. The motivation for this research was the update and enrichment of the Italian Tsunami Catalogue. The result was that evidence was found for two new cases of earthquake-induced tsunamis: these are the August 1916 Rimini and the October 1930 Ancona events. The bulk of the present research consisted in collecting all the available data on the earthquakes that affected the selected area in the past century and in identifying those potentially capable of generating tsunamis. During the study all the available material was gathered, which includes specific monographs and scientific papers, articles available in contemporary chronicles and in local and national newspapers. The final result of this research will improve our knowledge of the tsunamigenic activity of the central Adriatic sea and contribute to the assessment of the tsunami hazard and risk along these coasts, that especially in the peak season form one of the most densely populated areas of the Italian peninsula with flat and large beaches and water front resorts crowded of tourists.

  9. Transformation of tsunami waves passing through the Straits of the Kuril Islands

    Science.gov (United States)

    Kostenko, Irina; Kurkin, Andrey; Pelinovsky, Efim; Zaytsev, Andrey

    2015-04-01

    Pacific ocean and themselves Kuril Islands are located in the zone of high seismic activity, where underwater earthquakes cause tsunamis. They propagate across Pacific ocean and penetrates into the Okhotsk sea. It is natural to expect that the Kuril Islands reflect the Okhotsk sea from the Pacific tsunami waves. It has long been noted that the historical tsunami appeared less intense in the sea of Okhotsk in comparison with the Pacific coast of the Kuril Islands. Despite the fact that in the area of the Kuril Islands and in the Pacific ocean earthquakes with magnitude more than 8 occur, in the entire history of observations on the Okhotsk sea coast catastrophic tsunami was not registered. The study of the peculiarities of the propagation of historical and hypothetical tsunami in the North-Eastern part of the Pacific ocean was carried out in order to identify level of effect of the Kuril Islands and Straits on them. Tsunami sources were located in the Okhotsk sea and in the Pacific ocean. For this purpose, we performed a series of computational experiments using two bathymetries: 1) with use Kuril Islands; 2) without Kuril Islands. Magnitude and intensity of the tsunami, obtained during numerical simulation of height, were analyzed. The simulation results are compared with the observations. Numerical experiments have shown that in the simulation without the Kuril Islands tsunamis in the Okhotsk sea have higher waves, and in the Central part of the sea relatively quickly damped than in fact. Based on shallow-water equation tsunami numerical code NAMI DANCE was used for numerical simulations. This work was supported by ASTARTE project.

  10. Tsunami hazard and risk assessment in El Salvador

    Science.gov (United States)

    González, M.; González-Riancho, P.; Gutiérrez, O. Q.; García-Aguilar, O.; Aniel-Quiroga, I.; Aguirre, I.; Alvarez, J. A.; Gavidia, F.; Jaimes, I.; Larreynaga, J. A.

    2012-04-01

    Tsunamis are relatively infrequent phenomena representing a greater threat than earthquakes, hurricanes and tornadoes, causing the loss of thousands of human lives and extensive damage to coastal infrastructure around the world. Several works have attempted to study these phenomena in order to understand their origin, causes, evolution, consequences, and magnitude of their damages, to finally propose mechanisms to protect coastal societies. Advances in the understanding and prediction of tsunami impacts allow the development of adaptation and mitigation strategies to reduce risk on coastal areas. This work -Tsunami Hazard and Risk Assessment in El Salvador-, funded by AECID during the period 2009-12, examines the state of the art and presents a comprehensive methodology for assessing the risk of tsunamis at any coastal area worldwide and applying it to the coast of El Salvador. The conceptual framework is based on the definition of Risk as the probability of harmful consequences or expected losses resulting from a given hazard to a given element at danger or peril, over a specified time period (European Commission, Schneiderbauer et al., 2004). The HAZARD assessment (Phase I of the project) is based on propagation models for earthquake-generated tsunamis, developed through the characterization of tsunamigenic sources -sismotectonic faults- and other dynamics under study -tsunami waves, sea level, etc.-. The study area is located in a high seismic activity area and has been hit by 11 tsunamis between 1859 and 1997, nine of them recorded in the twentieth century and all generated by earthquakes. Simulations of historical and potential tsunamis with greater or lesser affection to the country's coast have been performed, including distant sources, intermediate and close. Deterministic analyses of the threats under study -coastal flooding- have been carried out, resulting in different hazard maps (maximum wave height elevation, maximum water depth, minimum tsunami

  11. An improvement of the GPS buoy system for detecting tsunami at far offshore

    Science.gov (United States)

    Kato, T.; Terada, Y.; Nagai, T.; Kawaguchi, K.; Koshimura, S.; Matsushita, Y.

    2012-12-01

    We have developed a GPS buoy system for detecting a tsunami before its arrival at coasts and thereby mitigating tsunami disaster. The system was first deployed in 1997 for a short period in the Sagami bay, south of Tokyo, for basic experiments, and then deployed off Ofunato city, northeastern part of Japan, for the period 2001-2004. The system was then established at about 13km south of Cape Muroto, southwestern part of Japan, since 2004. Five tsunamis of about 10cm have been observed in these systems, including 2001 Peru earthquake (Mw8.3), 2003 Tokachi-oki earthquake (Mw8.3), 2004 Off Kii Peninsula earthquake (Mw7.4), 2010 Chile earthquake (Mw8.8), and 2011 Tohoku-Oki earthquake (Mw9.0). These experiments clearly showed that GPS buoy is capable of detecting tsunami with a few centimeter accuracy and can be monitored in near real time by applying an appropriate filter, real-time data transmission using radio and dissemination of obtained records of sea surface height changes through internet. Considering that the system is a powerful tool to monitor sea surface variations due to wind as well as tsunami, the Ministry of Land, Infrastructure, Transport and Tourism implemented the system in a part of the Nationwide Ocean Wave information network for Ports and HArbourS (NOWPHAS) system and deployed the system at 15 sites along the coasts around the Japanese Islands. The system detected the tsunami due to the 11th March 2011 Tohoku-Oki earthquake with higher than 6m of tsunami height at the site Off South Iwate (Kamaishi). The Japan Meteorological Agency that was monitoring the record updated the level of the tsunami warning to the greatest value due to the result. Currently, the GPS buoy system uses a RTK-GPS which requires a land base for obtaining precise location of the buoy by a baseline analysis. This algorithm limits the distance of the buoy to, at most, 20km from the coast as the accuracy of positioning gets much worse as the baseline distance becomes longer

  12. A short history of tsunami research and countermeasures in Japan.

    Science.gov (United States)

    Shuto, Nobuo; Fujima, Koji

    2009-01-01

    The tsunami science and engineering began in Japan, the country the most frequently hit by local and distant tsunamis. The gate to the tsunami science was opened in 1896 by a giant local tsunami of the highest run-up height of 38 m that claimed 22,000 lives. The crucial key was a tide record to conclude that this tsunami was generated by a "tsunami earthquake". In 1933, the same area was hit again by another giant tsunami. A total system of tsunami disaster mitigation including 10 "hard" and "soft" countermeasures was proposed. Relocation of dwelling houses to high ground was the major countermeasures. The tsunami forecasting began in 1941. In 1960, the Chilean Tsunami damaged the whole Japanese Pacific coast. The height of this tsunami was 5-6 m at most. The countermeasures were the construction of structures including the tsunami breakwater which was the first one in the world. Since the late 1970s, tsunami numerical simulation was developed in Japan and refined to become the UNESCO standard scheme that was transformed to 22 different countries. In 1983, photos and videos of a tsunami in the Japan Sea revealed many faces of tsunami such as soliton fission and edge bores. The 1993 tsunami devastated a town protected by seawalls 4.5 m high. This experience introduced again the idea of comprehensive countermeasures, consisted of defense structure, tsunami-resistant town development and evacuation based on warning.

  13. American Samoa Energy Action Plan

    Energy Technology Data Exchange (ETDEWEB)

    Haase, Scott [National Renewable Energy Lab. (NREL), Golden, CO (United States); Esterly, Sean [National Renewable Energy Lab. (NREL), Golden, CO (United States); Herdrich, David [National Renewable Energy Lab. (NREL), Golden, CO (United States); Bodell, Tim [National Renewable Energy Lab. (NREL), Golden, CO (United States); Visser, Charles [National Renewable Energy Lab. (NREL), Golden, CO (United States)

    2013-08-01

    Describes the five near-term strategies selected by the American Samoa Renewable Energy Committee (ASREC) during action planning workshops conducted in May 2013, and outlines the actions being taken to implement those strategies. Each option is tied to a priority identified in the earlier draft American Samoa Strategic Energy Plan as being an essential component of reducing American Samoa'spetroleum energy consumption. The actions described for each strategy provide a roadmap to facilitate the implementation of each strategy. This document is intended to evolve along with the advancement of the projects, and will be updated to reflect progress.

  14. Modelling of historical tsunami in Eastern Indonesia: 1674 Ambon and 1992 Flores case studies

    Science.gov (United States)

    Pranantyo, Ignatius Ryan; Cummins, Phil; Griffin, Jonathan; Davies, Gareth; Latief, Hamzah

    2017-07-01

    In order to reliably assess tsunami hazard in eastern Indonesia, we need to understand how historical events were generated. Here we consider two such events: the 1674 Ambon and the 1992 Flores tsunamis. Firstly, Ambon Island suffered a devastating earthquake that generated a tsunami with 100 m run-up height on the north coast of the island in 1674. However, there is no known active fault around the island capable of generating such a gigantic wave. Rumphius' report describes that the initial wave was coming from three villages that collapsed immediately after the earthquake with width as far as a musket shot. Moreover, a very high tsunami was only observed locally. We suspect that a submarine landslide was the main cause of the gigantic tsunami on the north side of Ambon Island. Unfortunately, there is no data available to confirm if landslide have occurred in this region. Secondly, several tsunami source models for the 1992 Flores event have been suggested. However, the fault strike is quite different compare to the existing Flores back-arc thrust and has not been well validated against a tide gauge waveform at Palopo, Sulawesi. We considered a tsunami model based on Griffin, et al., 2015, extended with high resolution bathymetry laround Palopo, in order to validate the latest tsunami source model available. In general, the model produces a good agreement with tsunami waveforms, but arrives 10 minutes late compared to observed data. In addition, the source overestimates the tsunami inundation west of Maumere, and does not account for the presumed landslide tsunami on the east side of Flores Island.

  15. KESIAPAN JALUR DAN LOKASI EVAKUASI PUBLIK MENGHADAPI RESIKO BENCANA GEMPA DAN TSUNAMI DI KOTA PADANG (Studi Manajemen Bencana

    Directory of Open Access Journals (Sweden)

    Zikri Alhadi

    2014-06-01

    Full Text Available This article discusses about the preparedness of the evacuation lanes and sites for Padang citizens in facing earthquake and tsunami. In disaster management, the proper evacuation lanes and sites to be used for self-rescue plan is crucial to be fulfilled by stakeholders. In Padang city, some evacuation lanes and sites have not met the needs of the number of people predicted to evacuate when the disaster comes. This can be seen when several potential-tsunami-triggered quakes struck Padang, the citizens’ evacuation process, vertically or horizontally, were significantly challenged. The speed of reaching the evacuation site is important in saving many lives when tsunami really happens in Padang. Key words: disaster management, evacuation, earthquake and tsunami

  16. Coastal Tsunami and Risk Assessment for Eastern Mediterranean Countries

    Science.gov (United States)

    Kentel, E.; Yavuz, C.

    2017-12-01

    Tsunamis are rarely experienced events that have enormous potential to cause large economic destruction on the critical infrastructures and facilities, social devastation due to mass casualty, and environmental adverse effects like erosion, accumulation and inundation. Especially for the past two decades, nations have encountered devastating tsunami events. The aim of this study is to investigate risks along the Mediterranean coastline due to probable tsunamis based on simulations using reliable historical data. In order to do this, 50 Critical Regions, CRs, (i.e. city centers, agricultural areas and summer villages) and 43 Critical Infrastructures, CIs, (i.e. airports, ports & marinas and industrial structures) are determined to perform people-centered risk assessment along Eastern Mediterranean region covering 7 countries. These countries include Turkey, Syria, Lebanon, Israel, Egypt, Cyprus, and Libya. Bathymetry of the region is given in Figure 1. In this study, NAMI-DANCE is used to carry out tsunami simulations. Source of a sample tsunami simulation and maximum wave propagation in the study area for this sample tsunami are given in Figures 2 and 3, respectively.Richter magnitude,, focal depth, time of occurrence in a day and season are considered as the independent parameters of the earthquake. Historical earthquakes are used to generate reliable probability distributions for these parameters. Monte Carlo (MC) Simulations are carried out to evaluate overall risks at the coastline. Inundation level, population density, number of passenger or employee, literacy rate, annually income level and existence of human are used in risk estimations. Within each MC simulation and for each grid in the study area, people-centered tsunami risk for each of the following elements at risk is calculated: i. City centers ii. Agricultural areas iii. Summer villages iv. Ports and marinas v. Airports vi. Industrial structures Risk levels at each grid along the shoreline are

  17. Japan Catastrophic Earthquake and Tsunami in Fukushima Daiichi NPP; Is it Beyond Design Basis Accident or a Design Deficiency and Operator Unawareness?

    International Nuclear Information System (INIS)

    Gaafar, M.A.; Refeat, R.M.; EL-Kady, A.A.

    2012-01-01

    On March 11, 2011 a catastrophic earthquake and tsunami struck the north east coast of Japan. This catastrophe damaged fully or partially the six units of the Fukushima Daiichi Nuclear Power Plant.Questions were raised following the aftermath, whether it is beyond design basis accident caused by severe natural event or a failure by the Japanese authorities to plan to deal with such accident. There are many indications that the Utility of Fukushima Daiichi NPP, Tokyo Electric Power Company (TEPCO), did not pay enough attention to numerous facts about the incompatibility of the site and several design defects in the plant units. In fact there are three other NPP sites nearby Fukushima Daiichi Plant (about 30 to 60 Km far from Fukushima Daiichi NPP), with different site characteristics, which survived the same catastrophic earthquake and tsunami, but they were automatically turned into a safe shutdown state. These plants sites are Fukushima Daini Plant (4 units), Onagawa Plant (3 units) and Tokai Daini (II) Plant (one unit). In this paper, the aftermath Fukushima Daiichi plant integrity is pointed out. Some facts about the site and design concerns which could have implications on the accident are discussed. The response of Japan Authority is outlined and some remarks about their actions are underlined. The impacts of this disaster on the Nuclear Power Program worldwide are also discussed.

  18. Playing against nature: improving earthquake hazard mitigation

    Science.gov (United States)

    Stein, S. A.; Stein, J.

    2012-12-01

    The great 2011 Tohoku earthquake dramatically demonstrated the need to improve earthquake and tsunami hazard assessment and mitigation policies. The earthquake was much larger than predicted by hazard models, and the resulting tsunami overtopped coastal defenses, causing more than 15,000 deaths and $210 billion damage. Hence if and how such defenses should be rebuilt is a challenging question, because the defences fared poorly and building ones to withstand tsunamis as large as March's is too expensive,. A similar issue arises along the Nankai Trough to the south, where new estimates warning of tsunamis 2-5 times higher than in previous models raise the question of what to do, given that the timescale on which such events may occur is unknown. Thus in the words of economist H. Hori, "What should we do in face of uncertainty? Some say we should spend our resources on present problems instead of wasting them on things whose results are uncertain. Others say we should prepare for future unknown disasters precisely because they are uncertain". Thus society needs strategies to mitigate earthquake and tsunami hazards that make economic and societal sense, given that our ability to assess these hazards is poor, as illustrated by highly destructive earthquakes that often occur in areas predicted by hazard maps to be relatively safe. Conceptually, we are playing a game against nature "of which we still don't know all the rules" (Lomnitz, 1989). Nature chooses tsunami heights or ground shaking, and society selects the strategy to minimize the total costs of damage plus mitigation costs. As in any game of chance, we maximize our expectation value by selecting the best strategy, given our limited ability to estimate the occurrence and effects of future events. We thus outline a framework to find the optimal level of mitigation by balancing its cost against the expected damages, recognizing the uncertainties in the hazard estimates. This framework illustrates the role of the

  19. Resource utilization in the emergency department of a tertiary care university-based hospital in Tokyo before and after the 2011 Great East Japan earthquake and tsunami.

    Science.gov (United States)

    Shimada, Mai; Tanabe, Aska; Gunshin, Masataka; Riffenburgh, Robert H; Tanen, David A

    2012-12-01

    The objective of this study was to determine the resource utilization of a tertiary care Japanese emergency department (ED) that was not immediately adjacent to the area of the 2011 Great East Japan earthquake and tsunami. A retrospective chart review was performed at a tertiary care university-based urban ED located approximately 290 km from the primary site of destruction secondary to an earthquake measuring 9.0 on the Richter Scale and the resulting tsunami. All patients who presented for a period of twelve days before and twelve days after the disaster were included. Data were collected using preformed data collection sheets, and stored in an Excel file. Abstracted data included gender, time in the ED, intravenous fluid administration, blood transfusion, oxygen, laboratories, electrocardiograms (ECGs), radiographs, ultrasound, diagnoses, surgical and medical referrals, and prescriptions written. Ten percent of the charts were reviewed for accuracy, and an error rate reported. Data were analyzed using 2-tailed t-tests, Fisher's exact tests or rank sum tests. Bonferroni correction was used to adjust P values for multiple comparisons. Charts for 1193 patients were evaluated. The error rate for the abstracted data was 3.2% (95% CI, 2.4%-4.1%). Six hundred fifty-seven patients (53% male) were evaluated in the ED after the earthquake, representing a 23% increase in patient volume. Mean patient time spent in the ED decreased from 61 minutes to 52 minutes (median decrease from 35 minutes to 32 minutes; P = .005). Laboratory utilization decreased from 51% to 43% (P = .006). The percentage of patients receiving prescriptions increased from 48% to 54% (P = .002). There was no change in the number of patients evaluated for surgical complaints, but there was an increase in the number treated for medical or psychiatric complaints. There was a significant increase in the number of people utilizing the ED in Tokyo after the Great East Japan earthquake and tsunami. Time spent

  20. THE FRENCH TSUNAMI WARNING CENTER FOR THE MEDITERRANEAN AND NORTHEAST ATLANTIC: CENALT

    Directory of Open Access Journals (Sweden)

    H. Hébert

    2013-01-01

    Full Text Available CENALT (CENtre d’ALerte aux Tsunamis is responsible for the French National Tsunami Warning Centre (NTWC. The CENALT is established in the framework of the Unesco/IOC/ICG/NEAMTWS. Its objective is to transmit a warning message in less than fifteen minutes for any events that could trigger a tsunami in the Western Mediterranean Sea and the North- Eastern Atlantic Ocean. The data collected from French installations and from institutions of European and North African countries is processed with software that permits early epicenter location of seismic events and measurements of expected tsunami impacts on the shore. On-duty analysts revise interactively all the generated information and use references of historical tsunami and earthquake databases - as well as computed tsunami scenarios – in order to disseminate the more comprehensive message possible.

  1. How much does geometry of seismic sources matter in tsunami modeling? A sensitivity analysis for the Calabrian subduction interface

    Science.gov (United States)

    Tonini, R.; Maesano, F. E.; Tiberti, M. M.; Romano, F.; Scala, A.; Lorito, S.; Volpe, M.; Basili, R.

    2017-12-01

    The geometry of seismogenic sources could be one of the most important factors concurring to control the generation and the propagation of earthquake-generated tsunamis and their effects on the coasts. Since the majority of potentially tsunamigenic earthquakes occur offshore, the corresponding faults are generally poorly constrained and, consequently, their geometry is often oversimplified as a planar fault. The rupture area of mega-thrust earthquakes in subduction zones, where most of the greatest tsunamis have occurred, extends for tens to hundreds of kilometers both down dip and along strike, and generally deviates from the planar geometry. Therefore, the larger the earthquake size is, the weaker the planar fault assumption become. In this work, we present a sensitivity analysis aimed to explore the effects on modeled tsunamis generated by seismic sources with different degrees of geometric complexities. We focused on the Calabrian subduction zone, located in the Mediterranean Sea, which is characterized by the convergence between the African and European plates, with rates of up to 5 mm/yr. This subduction zone has been considered to have generated some past large earthquakes and tsunamis, despite it shows only in-slab significant seismic activity below 40 km depth and no relevant seismicity in the shallower portion of the interface. Our analysis is performed by defining and modeling an exhaustive set of tsunami scenarios located in the Calabrian subduction and using different models of the subduction interface with increasing geometrical complexity, from a planar surface to a highly detailed 3D surface. The latter was obtained from the interpretation of a dense network of seismic reflection profiles coupled with the analysis of the seismicity distribution. The more relevant effects due to the inclusion of 3D complexities in the seismic source geometry are finally highlighted in terms of the resulting tsunami impact.

  2. Tsunami Amplitude Estimation from Real-Time GNSS.

    Science.gov (United States)

    Jeffries, C.; MacInnes, B. T.; Melbourne, T. I.

    2017-12-01

    Tsunami early warning systems currently comprise modeling of observations from the global seismic network, deep-ocean DART buoys, and a global distribution of tide gauges. While these tools work well for tsunamis traveling teleseismic distances, saturation of seismic magnitude estimation in the near field can result in significant underestimation of tsunami excitation for local warning. Moreover, DART buoy and tide gauge observations cannot be used to rectify the underestimation in the available time, typically 10-20 minutes, before local runup occurs. Real-time GNSS measurements of coseismic offsets may be used to estimate finite faulting within 1-2 minutes and, in turn, tsunami excitation for local warning purposes. We describe here a tsunami amplitude estimation algorithm; implemented for the Cascadia subduction zone, that uses continuous GNSS position streams to estimate finite faulting. The system is based on a time-domain convolution of fault slip that uses a pre-computed catalog of hydrodynamic Green's functions generated with the GeoClaw shallow-water wave simulation software and maps seismic slip along each section of the fault to points located off the Cascadia coast in 20m of water depth and relies on the principle of the linearity in tsunami wave propagation. The system draws continuous slip estimates from a message broker, convolves the slip with appropriate Green's functions which are then superimposed to produce wave amplitude at each coastal location. The maximum amplitude and its arrival time are then passed into a database for subsequent monitoring and display. We plan on testing this system using a suite of synthetic earthquakes calculated for Cascadia whose ground motions are simulated at 500 existing Cascadia GPS sites, as well as real earthquakes for which we have continuous GNSS time series and surveyed runup heights, including Maule, Chile 2010 and Tohoku, Japan 2011. This system has been implemented in the CWU Geodesy Lab for the Cascadia

  3. Modelling of Charles Darwin's tsunami reports

    Science.gov (United States)

    Galiev, Shamil

    2010-05-01

    Darwin landed at Valdivia and Concepcion, Chile, just before, during, and after a great 1835 earthquake. He described his impressions and results of the earthquake-induced natural catastrophe in The Voyage of the Beagle. His description of the tsunami could easily be read as a report from Indonesia or Sri Lanka, after the catastrophic tsunami of 26 December 2004. In particular, Darwin emphasised the dependence of earthquake-induced waves on a form of the coast and the coastal depth: ‘… Talcuhano and Callao are situated at the head of great shoaling bays, and they have always suffered from this phenomenon; whereas, the town of Valparaiso, which is seated close on the border of a profound ocean... has never been overwhelmed by one of these terrific deluges…' . He reports also, that ‘… the whole body of the sea retires from the coast, and then returns in great waves of overwhelming force ...' (we cite the Darwin's sentences following researchspace. auckland. ac. nz/handle/2292/4474). The coastal evolution of a tsunami was analytically studied in many publications (see, for example, Synolakis, C.E., Bernard, E.N., 2006. Philos. Trans. R. Soc., Ser. A, 364, 2231-2265; Tinti, S., Tonini, R. 205. J.Fluid Mech., 535, 11-21). However, the Darwin's reports and the influence of the coastal depth on the formation and the evolution of the steep front and the profile of tsunami did not practically discuss. Recently, a mathematical theory of these phenomena was presented in researchspace. auckland. ac. nz/handle/2292/4474. The theory describes the waves which are excited due to nonlinear effects within a shallow coastal zone. The tsunami elevation is described by two components: . Here is the linear (prime) component. It describes the wave coming from the deep ocean. is the nonlinear component. This component may become very important near the coastal line. After that the theory of the shallow waves is used. This theory yields the linear equation for and the weakly

  4. Introduction to thematic collection "Historical and geological studies of earthquakes"

    Science.gov (United States)

    Satake, Kenji; Wang, Jian; Hammerl, Christa; Malik, Javed N.

    2017-12-01

    This thematic collection contains eight papers mostly presented at the 2016 AOGS meeting in Beijing. Four papers describe historical earthquake studies in Europe, Japan, and China; one paper uses modern instrumental data to examine the effect of giant earthquakes on the seismicity rate; and three papers describe paleoseismological studies using tsunami deposit in Japan, marine terraces in Philippines, and active faults in Himalayas. Hammerl (Geosci Lett 4:7, 2017) introduced historical seismological studies in Austria, starting from methodology which is state of the art in most European countries, followed by a case study for an earthquake of July 17, 1670 in Tyrol. Albini and Rovida (Geosci Lett 3:30, 2016) examined 114 historical records for the earthquake on April 6, 1667 on the east coast of the Adriatic Sea, compiled 37 Macroseismic Data Points, and estimated the epicenter and the size of the earthquake. Matsu'ura (Geosci Lett 4:3, 2017) summarized historical earthquake studies in Japan which resulted in about 8700 Intensity Data Points, assigned epicenters for 214 earthquakes between AD 599 and 1872, and estimated focal depth and magnitudes for 134 events. Wang et al. (Geosci Lett 4:4, 2017) introduced historical seismology in China, where historical earthquake archives include about 15,000 sources, and parametric catalogs include about 1000 historical earthquakes between 2300 BC and AD 1911. Ishibe et al. (Geosci Lett 4:5, 2017) tested the Coulomb stress triggering hypothesis for three giant (M 9) earthquakes that occurred in recent years, and found that at least the 2004 Sumatra-Andaman and 2011 Tohoku earthquakes caused the seismicity rate change. Ishimura (2017) re-estimated the ages of 11 tsunami deposits in the last 4000 years along the Sanriku coast of northern Japan and found that the average recurrence interval of those tsunamis as 350-390 years. Ramos et al. (2017) studied 1000-year-old marine terraces on the west coast of Luzon Island, Philippines

  5. An approximate method of short-term tsunami forecast and the hindcasting of some recent events

    Directory of Open Access Journals (Sweden)

    Yu. P. Korolev

    2011-11-01

    Full Text Available The paper presents a method for a short-term tsunami forecast based on sea level data from remote sites. This method is based on Green's function for the wave equation possessing the fundamental property of symmetry. This property is well known in acoustics and seismology as the reciprocity principle. Some applications of this principle on tsunami research are considered in the current study. Simple relationships and estimated transfer functions enabled us to simulate tsunami waveforms for any selected oceanic point based only on the source location and sea level data from a remote reference site. The important advantage of this method is that it is irrespective of the actual source mechanism (seismic, submarine landslide or other phenomena. The method was successfully applied to hindcast several recent tsunamis observed in the Northwest Pacific. The locations of the earthquake epicenters and the tsunami records from one of the NOAA DART sites were used as inputs for the modelling, while tsunami observations at other DART sites were used to verify the model. Tsunami waveforms for the 2006, 2007 and 2009 earthquake events near Simushir Island were simulated and found to be in good agreement with the observations. The correlation coefficients between the predicted and observed tsunami waveforms were from 0.50 to 0.85. Thus, the proposed method can be effectively used to simulate tsunami waveforms for the entire ocean and also for both regional and local tsunami warning services, assuming that they have access to the real-time sea level data from DART stations.

  6. American Samoa: Energy Action Plan

    Energy Technology Data Exchange (ETDEWEB)

    Ness, J. Erik [National Renewable Energy Lab. (NREL), Golden, CO (United States); Haase, Scott [National Renewable Energy Lab. (NREL), Golden, CO (United States); Conrad, Misty [National Renewable Energy Lab. (NREL), Golden, CO (United States)

    2016-09-01

    This document outlines actions being taken to reduce American Samoa's petroleum consumption. It describes the four near-term strategies selected by the American Samoa Renewable Energy Committee during action-planning workshops conducted in May 2016, and describes the steps that will need to be taken to implement those strategies.

  7. The SAFRR Tsunami Scenario: Improving Resilience for California from a Plausible M9 Earthquake near the Alaska Peninsula

    Science.gov (United States)

    Ross, S.; Jones, L.; Wilson, R. I.; Bahng, B.; Barberopoulou, A.; Borrero, J. C.; Brosnan, D.; Bwarie, J.; Geist, E. L.; Johnson, L.; Kirby, S. H.; Knight, W.; Long, K.; Lynett, P. J.; Miller, K.; Mortensen, C. E.; Nicolsky, D.; Oglesby, D. D.; Perry, S. C.; Plumlee, G. S.; Porter, K. A.; Real, C. R.; Ryan, K. J.; Suleimani, E.; Thio, H. K.; Titov, V.; Wein, A. M.; Whitmore, P.; Wood, N. J.

    2013-12-01

    The SAFRR Tsunami Scenario models a hypothetical but plausible tsunami, created by an Mw9.1 earthquake occurring offshore from the Alaskan peninsula, and its impacts on the California coast. We present the likely inundation areas, current velocities in key ports and harbors, physical damage and repair costs, economic consequences, environmental impacts, social vulnerability, emergency management, and policy implications for California associated with the tsunami scenario. The intended users are those who must make mitigation decisions before and rapid decisions during future tsunamis. Around a half million people would be present in the scenario's inundation area in residences, businesses, public venues, parks and beaches. Evacuation would likely be ordered for the State of California's maximum mapped tsunami inundation zone, evacuating an additional quarter million people from residences and businesses. Some island and peninsula communities would face particular evacuation challenges because of limited access options and short warning time, caused by the distance between Alaska and California. Evacuations may also be a challenge for certain dependent-care populations. One third of the boats in California's marinas could be damaged or sunk, costing at least 700 million in repairs to boats and docks, and potentially much more to address serious issues due to sediment transport and environmental contamination. Fires would likely start at many sites where fuel and petrochemicals are stored in ports and marinas. Tsunami surges and bores may travel several miles inland up coastal rivers. Debris clean-up and recovery of inundated and damaged areas will take days, months, or years depending on the severity of impacts and the available resources for recovery. The Ports of Los Angeles and Long Beach (POLA/LB) would be shut down for a miniμm of two days due to strong currents. Inundation of dry land in the ports would result in 100 million damages to cargo and additional

  8. Predicting the impact of tsunami in California under rising sea level

    Science.gov (United States)

    Dura, T.; Garner, A. J.; Weiss, R.; Kopp, R. E.; Horton, B.

    2017-12-01

    The flood hazard for the California coast depends not only on the magnitude, location, and rupture length of Alaska-Aleutian subduction zone earthquakes and their resultant tsunamis, but also on rising sea levels, which combine with tsunamis to produce overall flood levels. The magnitude of future sea-level rise remains uncertain even on the decadal scale, with future sea-level projections becoming even more uncertain at timeframes of a century or more. Earthquake statistics indicate that timeframes of ten thousand to one hundred thousand years are needed to capture rare, very large earthquakes. Because of the different timescales between reliable sea-level projections and earthquake distributions, simply combining the different probabilities in the context of a tsunami hazard assessment may be flawed. Here, we considered 15 earthquakes between Mw 8 to Mw 9.4 bound by -171oW and -140oW of the Alaska-Aleutian subduction zone. We employed 24 realizations at each magnitude with random epicenter locations and different fault length-to-width ratios, and simulated the tsunami evolution from these 360 earthquakes at each decade from the years 2000 to 2200. These simulations were then carried out for different sea-level-rise projections to analyze the future flood hazard for California. Looking at the flood levels at tide gauges, we found that the flood level simulated at, for example, the year 2100 (including respective sea-level change) is different from the flood level calculated by adding the flood for the year 2000 to the sea-level change prediction for the year 2100. This is consistent for all sea-level rise scenarios, and this difference in flood levels range between 5% and 12% for the larger half of the given magnitude interval. Focusing on flood levels at the tide gauge in the Port of Los Angeles, the most probable flood level (including all earthquake magnitudes) in the year 2000 was 5 cm. Depending on the sea-level predictions, in the year 2050 the most probable

  9. Social Participation and Disaster Risk Reduction Behaviors in Tsunami Prone Areas

    Science.gov (United States)

    Witvorapong, Nopphol; Muttarak, Raya; Pothisiri, Wiraporn

    2015-01-01

    This paper examines the relationships between social participation and disaster risk reduction actions. A survey of 557 households in tsunami prone areas in Phang Nga, Thailand was conducted following the 2012 Indian Ocean earthquakes. We use a multivariate probit model to jointly estimate the likelihood of undertaking three responses to earthquake and tsunami hazards (namely, (1) following disaster-related news closely, (2) preparing emergency kits and/or having a family emergency plan, and (3) having an intention to migrate) and community participation. We find that those who experienced losses from the 2004 tsunami are more likely to participate in community activities and respond to earthquake hazards. Compared to men, women are more likely to prepare emergency kits and/or have an emergency plan and have a greater intention to migrate. Living in a community with a higher proportion of women with tertiary education increases the probability of engaging in community activities and carrying out disaster risk reduction measures. Individuals who participate in village-based activities are 5.2% more likely to undertake all three risk reduction actions compared to those not engaging in community activities. This implies that encouraging participation in community activities can have positive externalities in disaster mitigation. PMID:26153891

  10. Fractal Analysis on the Correlation of Coastal Line Geometry and Tsunami Impact in Maumere, Flores, Indonesia

    Directory of Open Access Journals (Sweden)

    SARI BAHAGIARTI KUSUMAYUDHA

    2011-12-01

    Full Text Available Almost all of the Indonesian territories are high potential of geologic disaster, such as earthquake, tsunami, volcanic eruptions and landslides, because the country belongs to tectonically active areas of the world. There are three big lithosperic plates interacting one with one another and influencing the tectonic setting of Indonesia. The plates are Indo-Australia plate, Eurasia plate and Pacific plate. Indo-Australia plate moves relatively northward by about 9 cm/year, Eurasia plate creeps south eastward with approximately 7 cm/year speed, and Pacific plate moves to the west with around 11 cm/year velocity. In the meeting line of the plates, about 300 km to the south of Indonesian islands, there is the subduction zone that become places, where earthquake focuses are generated. Earthquakes from submarine source with more than 6.5 magnitude have the potential to generate tsunami. Areas situated along the south coast of Indonesia islands are vulnerable to tsunami, because directly facing the boundary lines between Eurasia plate and Indo-Australia plate. This study verified that there is positive correlation between coastal line geometry and the tsunami impact, based on fractal analysis. The case study is Maumere, Flores island, East Nusa Tenggara, Indonesia. Result of the study is expected to be used for predicting the tsunami impact intensiveness at other areas.

  11. Tsunami-tendenko and morality in disasters.

    Science.gov (United States)

    Kodama, Satoshi

    2015-05-01

    Disaster planning challenges our morality. Everyday rules of action may need to be suspended during large-scale disasters in favour of maxims that that may make prudential or practical sense and may even be morally preferable but emotionally hard to accept, such as tsunami-tendenko. This maxim dictates that the individual not stay and help others but run and preserve his or her life instead. Tsunami-tendenko became well known after the great East Japan earthquake on 11 March 2011, when almost all the elementary and junior high school students in one city survived the tsunami because they acted on this maxim that had been taught for several years. While tsunami-tendenko has been praised, two criticisms of it merit careful consideration: one, that the maxim is selfish and immoral; and two, that it goes against the natural tendency to try to save others in dire need. In this paper, I will explain the concept of tsunami-tendenko and then respond to these criticisms. Such ethical analysis is essential for dispelling confusion and doubts about evacuation policies in a disaster. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://group.bmj.com/group/rights-licensing/permissions.

  12. Identification of tsunami deposits and liquefaction features in the Gargano area (Italy: paleoseismological implication

    Directory of Open Access Journals (Sweden)

    L. Graziani

    2003-06-01

    Full Text Available The Gargano region (Southeastern Italy was hit by a M = 6.8 earthquake and inundated by a subsequent tsunami in 1627. To better define the hazard in the region, we searched for evidence of this and prior earthquakes in the geologic record. We identified potential earthquake-related liquefaction features and tsunami deposits in the stratigraphic sequences of the marsh areas both north and south of the Gargano promontory. We recognized clear liquefaction features and possible tsunamigenic sands that can be related to the 1627 seismic event in irrigation ditch exposures and gouge cores along the Northern Gargano coast. In total, six potential tsunami sand deposits have been recognized in two areas located close to the northern and southern coasts of the Gargano promontory. However, ambiguous evidence comes from the paleontological analysis of these sands. Although fragments of marine shells have been found in the coarser portion of the sand samples, foraminifera and ostracods assemblages are typical of brackish water condition. Radiocarbon dating of three of these deposits from the Northern Gargano coast, near the town of Lesina, suggests an average recurrence interval of 1700 years for tsunami events in this area. Assuming that all the paleotsunamis are related to the same seismogenic source responsible for the 1627 earthquake, this average recurrence interval may be typical for that source. Radiocarbon dating of three sand layers observed on the southern coast, close to the city of Manfredonia, suggests that the average recurrence time for violent sea inundation there is about 1200 years.

  13. Survey of the July 17, 2006 Central Javan tsunami reveals 21m runup heights

    Science.gov (United States)

    Fritz, H.; Goff, J.; Harbitz, C.; McAdoo, B.; Moore, A.; Latief, H.; Kalligeris, N.; Kodjo, W.; Uslu, B.; Titov, V.; Synolakis, C.

    2006-12-01

    The Monday, July 17, 2006 Central Javan 7.7 earthquake triggered a substantial tsunami that killed 600 people along a 200km stretch of coastline. The earthquake was not reported felt along the coastline. While there was a warning issued by the PTWC, it did not trigger an evacuation warning (Synolakis, 2006). The Indian Ocean Tsunami Warning System announced by UNESCO as operational in a press release two weeks before the event did not function as promised. There were no seismic recordings transmitted to the PTWC, and two German tsunameter buoys had broken off their moorings and were not operational. Lifeguards along a tourist beach reported that while the observed the harbinger shoreline recession, they attributed to exteme storm waves that were pounding the beaches that day. Had the tsunami struck on the preceding Sunday, instead of Monday, the death toll would had been far higher. The International Tsunami Survey Team (ITST) surveyed the coastline measuring runup, inundation, flow depths and sediment deposition, with standard methods (Synolakis and Okal, 2004). Runup values ranged up to 21m with several readings over 10m, while sand sheets up to 15cm were deposited. The parent earthquake was similar, albeit of smaller magnitude, to the 1994 East Javan tsunami, which struck about 200km east (Synolakis, et al, 1995) and reached a maximum of 11m runup height only at one location on steep cliffs. The unusual distribution of runup heights, and the pronounced extreme values near Nusa Kambangan, suggest a local coseismic landslide may have triggered an additional tsunami (Okal and Synolakis, 2005). The ITST observed that many coastal villages were completely abandoned after the tsunami, even in locales where there were no casualties. Whether residents will return is uncertain, but it is clear that an education campaign in tsunami hazard mitigation is urgently needed. In the aftermath of the tsunami, the Government of Indonesia enforced urgent emergency preparedness

  14. Study of tsunami propagation in the Ligurian Sea

    Directory of Open Access Journals (Sweden)

    E. Pelinovsky

    2001-01-01

    Full Text Available Tsunami propagation is analyzed for the Ligurian Sea with particular attention on the French coasts of the Mediterranean. Historical data of tsunami manifestation on the French coast are analyzed for the period 2000 B.C.–1991 A.D. Numerical simulations of potential and historical tsunamis in the Ligurian Sea are done in the context of the nonlinear shallow water theory. Tsunami wave heights as well as their distribution function is calculated for historical tsunamis and it is shown that the log-normal distribution describes reasonably the simulated data. This demonstrates the particular role of bottom irregularities for the wave height distribution function near the coastlines. Also, spectral analysis of numerical tide-gauge records is done for potential tsunamis, revealing the complex resonant interactions between the tsunami waves and the bottom oscillations. It is shown that for an earthquake magnitude of 6.8 (averaged value for the Mediterranean Sea the tsunami phenomenon has a very local character but with long duration. For sources located near the steep continental slope in the vicinity of the French-Italian Rivera, the tsunami tide-gauge records in the vicinity of Cannes – Imperia present irregular oscillations with a characteristic period of 20–30 min and a total duration of 10–20 h. For the western French coasts the amplitudes are significantly less with characteristic low-frequency oscillations (period of 40 min–1 h.

  15. A probabilistic tsunami hazard assessment for Indonesia

    Science.gov (United States)

    Horspool, N.; Pranantyo, I.; Griffin, J.; Latief, H.; Natawidjaja, D. H.; Kongko, W.; Cipta, A.; Bustaman, B.; Anugrah, S. D.; Thio, H. K.

    2014-11-01

    Probabilistic hazard assessments are a fundamental tool for assessing the threats posed by hazards to communities and are important for underpinning evidence-based decision-making regarding risk mitigation activities. Indonesia has been the focus of intense tsunami risk mitigation efforts following the 2004 Indian Ocean tsunami, but this has been largely concentrated on the Sunda Arc with little attention to other tsunami prone areas of the country such as eastern Indonesia. We present the first nationally consistent probabilistic tsunami hazard assessment (PTHA) for Indonesia. This assessment produces time-independent forecasts of tsunami hazards at the coast using data from tsunami generated by local, regional and distant earthquake sources. The methodology is based on the established monte carlo approach to probabilistic seismic hazard assessment (PSHA) and has been adapted to tsunami. We account for sources of epistemic and aleatory uncertainty in the analysis through the use of logic trees and sampling probability density functions. For short return periods (100 years) the highest tsunami hazard is the west coast of Sumatra, south coast of Java and the north coast of Papua. For longer return periods (500-2500 years), the tsunami hazard is highest along the Sunda Arc, reflecting the larger maximum magnitudes. The annual probability of experiencing a tsunami with a height of > 0.5 m at the coast is greater than 10% for Sumatra, Java, the Sunda islands (Bali, Lombok, Flores, Sumba) and north Papua. The annual probability of experiencing a tsunami with a height of > 3.0 m, which would cause significant inundation and fatalities, is 1-10% in Sumatra, Java, Bali, Lombok and north Papua, and 0.1-1% for north Sulawesi, Seram and Flores. The results of this national-scale hazard assessment provide evidence for disaster managers to prioritise regions for risk mitigation activities and/or more detailed hazard or risk assessment.

  16. A~probabilistic tsunami hazard assessment for Indonesia

    Science.gov (United States)

    Horspool, N.; Pranantyo, I.; Griffin, J.; Latief, H.; Natawidjaja, D. H.; Kongko, W.; Cipta, A.; Bustaman, B.; Anugrah, S. D.; Thio, H. K.

    2014-05-01

    Probabilistic hazard assessments are a fundamental tool for assessing the threats posed by hazards to communities and are important for underpinning evidence based decision making on risk mitigation activities. Indonesia has been the focus of intense tsunami risk mitigation efforts following the 2004 Indian Ocean Tsunami, but this has been largely concentrated on the Sunda Arc, with little attention to other tsunami prone areas of the country such as eastern Indonesia. We present the first nationally consistent Probabilistic Tsunami Hazard Assessment (PTHA) for Indonesia. This assessment produces time independent forecasts of tsunami hazard at the coast from tsunami generated by local, regional and distant earthquake sources. The methodology is based on the established monte-carlo approach to probabilistic seismic hazard assessment (PSHA) and has been adapted to tsunami. We account for sources of epistemic and aleatory uncertainty in the analysis through the use of logic trees and through sampling probability density functions. For short return periods (100 years) the highest tsunami hazard is the west coast of Sumatra, south coast of Java and the north coast of Papua. For longer return periods (500-2500 years), the tsunami hazard is highest along the Sunda Arc, reflecting larger maximum magnitudes along the Sunda Arc. The annual probability of experiencing a tsunami with a height at the coast of > 0.5 m is greater than 10% for Sumatra, Java, the Sunda Islands (Bali, Lombok, Flores, Sumba) and north Papua. The annual probability of experiencing a tsunami with a height of >3.0 m, which would cause significant inundation and fatalities, is 1-10% in Sumatra, Java, Bali, Lombok and north Papua, and 0.1-1% for north Sulawesi, Seram and Flores. The results of this national scale hazard assessment provide evidence for disaster managers to prioritise regions for risk mitigation activities and/or more detailed hazard or risk assessment.

  17. Observation-based Quantitative Uncertainty Estimation for Realtime Tsunami Inundation Forecast using ABIC and Ensemble Simulation

    Science.gov (United States)

    Takagawa, T.

    2016-12-01

    An ensemble forecasting scheme for tsunami inundation is presented. The scheme consists of three elemental methods. The first is a hierarchical Bayesian inversion using Akaike's Bayesian Information Criterion (ABIC). The second is Montecarlo sampling from a probability density function of multidimensional normal distribution. The third is ensamble analysis of tsunami inundation simulations with multiple tsunami sources. Simulation based validation of the model was conducted. A tsunami scenario of M9.1 Nankai earthquake was chosen as a target of validation. Tsunami inundation around Nagoya Port was estimated by using synthetic tsunami waveforms at offshore GPS buoys. The error of estimation of tsunami inundation area was about 10% even if we used only ten minutes observation data. The estimation accuracy of waveforms on/off land and spatial distribution of maximum tsunami inundation depth is demonstrated.

  18. Role of Compressibility on Tsunami Propagation

    Science.gov (United States)

    Abdolali, Ali; Kirby, James T.

    2017-12-01

    In the present paper, we aim to reduce the discrepancies between tsunami arrival times evaluated from tsunami models and real measurements considering the role of ocean compressibility. We perform qualitative studies to reveal the phase speed reduction rate via a modified version of the Mild Slope Equation for Weakly Compressible fluid (MSEWC) proposed by Sammarco et al. (2013). The model is validated against a 3-D computational model. Physical properties of surface gravity waves are studied and compared with those for waves evaluated from an incompressible flow solver over realistic geometry for 2011 Tohoku-oki event, revealing reduction in phase speed.Plain Language SummarySubmarine earthquakes and submarine mass failures (SMFs), can generate long gravitational waves (or tsunamis) that propagate at the free surface. Tsunami waves can travel long distances and are known for their dramatic effects on coastal areas. Nowadays, numerical models are used to reconstruct the tsunamigenic events for many scientific and socioeconomic aspects i.e. Tsunami Early Warning Systems, inundation mapping, risk and hazard analysis, etc. A number of typically neglected parameters in these models cause discrepancies between model outputs and observations. Most of the tsunami models predict tsunami arrival times at distant stations slightly early in comparison to observations. In this study, we show how ocean compressibility would affect the tsunami wave propagation speed. In this framework, an efficient two-dimensional model equation for the weakly compressible ocean has been developed, validated and tested for simplified and real cases against three dimensional and incompressible solvers. Taking the effect of compressibility, the phase speed of surface gravity waves is reduced compared to that of an incompressible fluid. Then, we used the model for the case of devastating Tohoku-Oki 2011 tsunami event, improving the model accuracy. This study sheds light for future model development

  19. The EarthScope Plate Boundary Observatory and allied networks, the makings of nascent Earthquake and Tsunami Early Warning System in Western North America.

    Science.gov (United States)

    Mattioli, Glen; Mencin, David; Hodgkinson, Kathleen; Meertens, Charles; Phillips, David; Blume, Fredrick; Berglund, Henry; Fox, Otina; Feaux, Karl

    2016-04-01

    The NSF-funded GAGE Facility, managed by UNAVCO, operates approximately ~1300 GNSS stations distributed across North and Central America and in the circum-Caribbean. Following community input starting in 2011 from several workshops and associated reports,UNAVCO has been exploring ways to increase the capability and utility of the geodetic resources under its management to improve our understanding in diverse areas of geophysics including properties of seismic, volcanic, magmatic and tsunami deformation sources. Networks operated by UNAVCO for the NSF have the potential to profoundly transform our ability to rapidly characterize events, provide rapid characterization and warning, as well as improve hazard mitigation and response. Specific applications currently under development include earthquake early warning, tsunami early warning, and tropospheric modeling with university, commercial, non-profit and government partners on national and international scales. In the case of tsunami early warning, for example, an RT-GNSS network can provide multiple inputs in an operational system starting with rapid assessment of earthquake sources and associated deformation, which leads to the initial model of ocean forcing and tsunami generation. In addition, terrestrial GNSScan provide direct measurements of the tsunami through the associated traveling ionospheric disturbance from several 100's of km away as they approach the shoreline,which can be used to refine tsunami inundation models. Any operational system like this has multiple communities that rely on a pan-Pacific real-time open data set. Other scientific and operational applications for high-rate GPS include glacier and ice sheet motions, tropospheric modeling, and better constraints on the dynamics of space weather. Combining existing data sets and user communities, for example seismic data and tide gauge observations, with GNSS and Met data products has proven complicated because of issues related to metadata

  20. Locating the Tohoku-Oki 2011 tsunami source using acoustic-gravity waves

    OpenAIRE

    Andriamiranto Raveloson; Rainer Kind; Xiaohui Yuan; L. Cerana

    2012-01-01

    The giant Tohoku-Oki earthquake of 11 March 2011 in offshore Japan did not only generate tsunami waves in the ocean but also infrasound (or acoustic-gravity) waves in the atmosphere. We indentified ultra-long-period signals (>500s) in the recordings of infrasound stations in northeast Asia, the northwest Pacific, and Alaska. Their source was fond close to the earthquake epicenter. Therefore, we conclude that in general, infrasound observations after a large offshore earthquake are evidence th...

  1. An automatic tsunami warning system: TREMORS application in Europe

    Science.gov (United States)

    Reymond, D.; Robert, S.; Thomas, Y.; Schindelé, F.

    1996-03-01

    An integrated system named TREMORS (Tsunami Risk Evaluation through seismic Moment of a Real-time System) has been installed in EVORA station, in Portugal which has been affected by historical tsunamis. The system is based on a three component long period seismic station linked to a compatible IBM_PC with a specific software. The goals of this system are the followings: detect earthquake, locate them, compute their seismic moment, give a seismic warning. The warnings are based on the seismic moment estimation and all the processing are made automatically. The finality of this study is to check the quality of estimation of the main parameters of interest in a goal of tsunami warning: the location which depends of azimuth and distance, and at last the seismic moment, M 0, which controls the earthquake size. The sine qua non condition for obtaining an automatic location is that the 3 main seismic phases P, S, R must be visible. This study gives satisfying results (automatic analysis): ± 5° errors in azimuth and epicentral distance, and a standard deviation of less than a factor 2 for the seismic moment M 0.

  2. GPS water level measurements for Indonesia's Tsunami Early Warning System

    Directory of Open Access Journals (Sweden)

    T. Schöne

    2011-03-01

    Full Text Available On Boxing Day 2004, a severe tsunami was generated by a strong earthquake in Northern Sumatra causing a large number of casualties. At this time, neither an offshore buoy network was in place to measure tsunami waves, nor a system to disseminate tsunami warnings to local governmental entities. Since then, buoys have been developed by Indonesia and Germany, complemented by NOAA's Deep-ocean Assessment and Reporting of Tsunamis (DART buoys, and have been moored offshore Sumatra and Java. The suite of sensors for offshore tsunami detection in Indonesia has been advanced by adding GPS technology for water level measurements.

    The usage of GPS buoys in tsunami warning systems is a relatively new approach. The concept of the German Indonesian Tsunami Early Warning System (GITEWS (Rudloff et al., 2009 combines GPS technology and ocean bottom pressure (OBP measurements. Especially for near-field installations where the seismic noise may deteriorate the OBP data, GPS-derived sea level heights provide additional information.

    The GPS buoy technology is precise enough to detect medium to large tsunamis of amplitudes larger than 10 cm. The analysis presented here suggests that for about 68% of the time, tsunamis larger than 5 cm may be detectable.

  3. Evidence of Past Large Storms or Tsunamis from an Uplifted Section of the Southern Hikurangi Margin, Wairarapa Coast, New Zealand

    Science.gov (United States)

    Mitchell, S. P.; Jessica, P.; Clark, K.; Kosciuch, T. J.; Reinhardt, E. G.

    2017-12-01

    Evidence of past large storms or tsunamis from an uplifted section of the southern Hikurangi margin, Wairarapa coast, New Zealand Stephen Mitchell1, Jessica Pilarczyk1, Kate Clark2, Thomas Kosciuch1, Eduard Reinhardt31University of Southern Mississippi, Department of Marine Science 2GNS Science, New Zealand 3McMaster University The Hikurangi margin, located along the east coast of New Zealand, has generated multiple tsunamigenic-earthquakes in the historic times that have impacted coastlines of the North Island. Knowledge of the possible magnitudes and recurrence intervals associated with Hikurangi earthquakes and tsunamis is necessary to understand and mitigate hazards facing New Zealand's coasts. Events such as the 1931 Napier earthquake, which caused severe ground shaking, and the Gisborne tsunami of 1947 that reached 10 meters high, demonstrate the earthquake and tsunami hazards associated with the Hikurangi margin. To better understand these hazards, longer-term geologic records are needed. Along the Wairarapa coast of the North Island of New Zealand, marine terraces provide evidence for multiple Hikurangi earthquakes over the past 7,000 years. Evidence for possible tsunami inundation in this area has also been discovered, but the record is patchy in spatial and temporal extent. We found three anomalous sand layers preserved within an uplifted beach exposure along the Wairarapa coast. The sand layers, consisting of very fine to coarse sand (3.5-0.8 Φ), sharply overlie paleosols containing fine to medium sized silt (6.1-7.1 Φ) in a sequence that extends for approximately 400 meters along shore. We assign a marine origin to the sand layers because they contain relatively high elemental concentrations of calcium and barium. By contrast, the paleosols contained relatively high elemental concentrations of iron. The marine sands contain evidence in support of tsunami inundation; rip-up clasts, coarse pulses, fining upward sequences, and erosive contacts were

  4. High tsunami risk at northern tip of Sumatra as a result of the activity of the Sumatra Fault Zone (SFZ) combined with coastal landslides

    Science.gov (United States)

    Haridhi, H. A.; Huang, B. S.; Wen, K. L.; Mirza, A.; Rizal, S.; Purnawan, S.; Fajri, I.; Klingelhoefer, F.; Liu, C. S.; Lee, C. S.; Wilson, C. R.

    2017-12-01

    The lesson learned from the 12 January 2010, Mw 7.0 Haiti earthquake has shown that an earthquake with strike-slip faulting can produce a significant tsunami. This occasion is rare since in the fact of the fault consist predominantly of lateral motion, which is rarely associated with significant uplift or tsunami generation. Yet, another hint from this event, that this earthquake was accompanied by a coastal landslide. Again, there were only few records of a submarine slides as a primary source that generate a tsunami. Hence, the Haiti Mw 7.0 earthquake was generated by these combined mechanisms, i.e. strike-slip faulting earthquake and coastal landslide. In reflecting this event, the Sumatra region exhibit almost identical situation, where the right lateral strike-slip faulting of Sumatra Fault Zone (SFZ) is located. In this study, we are focusing at the northern tip of SFZ at Aceh Province. The reason we focused our study at its northern tip is that, since the Sumatra-Andaman mega earthquake and tsunami on 26 December 2004, which occurred at the subduction zone, there were no records of significant earthquake along the SFZ, where at this location the SFZ is divided into two faults, i.e. Aceh and Seulimeum faults. This study aimed as a mitigation effort, if an earthquake happened at these faults, do we observe a similar result as that happened at Haiti or not. To do so, we access the high-resolution shallow bathymetry data that acquired through a Community-Based Bathymetric Survey (CBBS), examines five scanned Single Channel Seismic (SCS) reflections data, perform the slope stability analysis and that simulate the tsunami using Cornell Multi-grid Coupled Tsunami Model (COMCOT) model with a combined source of fault activity and submarine landslide. The result shows that, by these combined mechanisms, if the earthquake as large as 7 Mw or larger, it could produce a tsunami as high as 6 meters along the coast. The detailed shallow bathymetric and the slope stability

  5. Earthquake-triggered landslides along the Hyblean-Malta Escarpment (off Augusta, eastern Sicily, Italy) - assessment of the related tsunamigenic potential

    Science.gov (United States)

    Ausilia Paparo, Maria; Armigliato, Alberto; Pagnoni, Gianluca; Zaniboni, Filippo; Tinti, Stefano

    2017-02-01

    Eastern Sicily is affected by earthquakes and tsunamis of local and remote origin, which is known through numerous historical chronicles. Recent studies have put emphasis on the role of submarine landslides as the direct cause of the main local tsunamis, envisaging that earthquakes (in 1693 and 1908) did produce a tsunami, but also that they triggered mass failures that were able to generate an even larger tsunami. The debate is still open, and though no general consensus has been found among scientists so far, this research had the merit to attract attention on possible generation of tsunamis by landslides off Sicily. In this paper we investigate the tsunami potential of mass failures along one sector of the Hyblean-Malta Escarpment (HME). facing Augusta. The HME is the main offshore geological structure of the region running almost parallel to the coast, off eastern Sicily. Here, bottom morphology and slope steepness favour soil failures. In our work we study slope stability under seismic load along a number of HME transects by using the Minimun Lithostatic Deviation (MLD) method, which is based on the limit-equilibrium theory. The main goal is to identify sectors of the HME that could be unstable under the effect of realistic earthquakes. We estimate the possible landslide volume and use it as input for numerical codes to simulate the landslide motion and the consequent tsunami. This is an important step for the assessment of the tsunami hazard in eastern Sicily and for local tsunami mitigation policies. It is also important in view of tsunami warning system since it can help to identify the minimum earthquake magnitude capable of triggering destructive tsunamis induced by landslides, and therefore to set up appropriate knowledge-based criteria to launch alert to the population.

  6. A submarine landslide source for the devastating 1964 Chenega tsunami, southern Alaska

    Science.gov (United States)

    Brothers, Daniel; Haeussler, Peter J.; Lee Liberty,; David Finlayson,; Geist, Eric L.; Labay, Keith A.; Michael Byerly,

    2016-01-01

    During the 1964 Great Alaska earthquake (Mw 9.2), several fjords, straits, and bays throughout southern Alaska experienced significant tsunami runup of localized, but unexplained origin. Dangerous Passage is a glacimarine fjord in western Prince William Sound, which experienced a tsunami that devastated the village of Chenega where 23 of 75 inhabitants were lost – the highest relative loss of any community during the earthquake. Previous studies suggested the source of the devastating tsunami was either from a local submarine landslide of unknown origin or from coseismic tectonic displacement. Here we present new observations from high-resolution multibeam bathymetry and seismic reflection surveys conducted in the waters adjacent to the village of Chenega. The seabed morphology and substrate architecture reveal a large submarine landslide complex in water depths of 120–360 m. Analysis of bathymetric change between 1957 and 2014 indicates the upper 20–50 m (∼0.7 km3) of glacimarine sediment was destabilized and evacuated from the steep face of a submerged moraine and an adjacent ∼21 km2 perched sedimentary basin. Once mobilized, landslide debris poured over the steep, 130 m-high face of a deeper moraine and then blanketed the terminal basin (∼465 m water depth) in 11 ± 5 m of sediment. These results, combined with inverse tsunami travel-time modeling, suggest that earthquake- triggered submarine landslides generated the tsunami that struck the village of Chenega roughly 4 min after shaking began. Unlike other tsunamigenic landslides observed in and around Prince William Sound in 1964, the failures in Dangerous Passage are not linked to an active submarine delta. The requisite environmental conditions needed to generate large submarine landslides in glacimarine fjords around the world may be more common than previously thought. 

  7. Evaluation of tsunami risk in Heraklion city, Crete, Greece, by using GIS methods

    Science.gov (United States)

    Triantafyllou, Ioanna; Fokaefs, Anna; Novikova, Tatyana; Papadopoulos, Gerasimos A.; Vaitis, Michalis

    2016-04-01

    The Hellenic Arc is the most active seismotectonic structure in the Mediterranean region. The island of Crete occupies the central segment of the arc which is characterized by high seismic and tsunami activity. Several tsunamis generated by large earthquakes, volcanic eruptions and landslides were reported that hit the capital city of Heraklion in the historical past. We focus our tsunami risk study in the northern coastal area of Crete (ca. 6 km in length and 1 km in maximum width) which includes the western part of the city of Heraklion and a large part of the neighboring municipality of Gazi. The evaluation of tsunami risk included calculations and mapping with QGIS of (1) cost for repairing buildings after tsunami damage, (2) population exposed to tsunami attack, (3) optimum routes and times for evacuation. To calculate the cost for building reparation after a tsunami attack we have determined the tsunami inundation zone in the study area after numerical simulations for extreme tsunami scenarios. The geographical distribution of buildings per building block, obtained from the 2011 census data of the Hellenic Statistical Authority (EL.STAT) and satellite data, was mapped. By applying the SCHEMA Damage Tool we assessed the building vulnerability to tsunamis according to the types of buildings and their expected damage from the hydrodynamic impact. A set of official cost rates varying with the building types and the damage levels, following standards set by the state after the strong damaging earthquakes in Greece in 2014, was applied to calculate the cost of rebuilding or repairing buildings damaged by the tsunami. In the investigation of the population exposed to tsunami inundation we have used the interpolation method to smooth out the population geographical distribution per building block within the inundation zone. Then, the population distribution was correlated with tsunami hydrodynamic parameters in the inundation zone. The last approach of tsunami risk

  8. Unusually large tsunamis frequent a currently creeping part of the Aleutian megathrust

    Science.gov (United States)

    Witter, Robert C.; Carver, G.A.; Briggs, Richard; Gelfenbaum, Guy R.; Koehler, R.D.; La Selle, SeanPaul M.; Bender, Adrian M.; Engelhart, S.E.; Hemphill-Haley, E.; Hill, Troy D.

    2016-01-01

    Current models used to assess earthquake and tsunami hazards are inadequate where creep dominates a subduction megathrust. Here we report geological evidence for large tsunamis, occurring on average every 300–340 years, near the source areas of the 1946 and 1957 Aleutian tsunamis. These areas bookend a postulated seismic gap over 200 km long where modern geodetic measurements indicate that the megathrust is currently creeping. At Sedanka Island, evidence for large tsunamis includes six sand sheets that blanket a lowland facing the Pacific Ocean, rise to 15 m above mean sea level, contain marine diatoms, cap terraces, adjoin evidence for scour, and date from the past 1700 years. The youngest sheet, and modern drift logs found as far as 800 m inland and >18 m elevation, likely record the 1957 tsunami. Modern creep on the megathrust coexists with previously unrecognized tsunami sources along this part of the Aleutian Subduction Zone.

  9. A review of potential tsunami impacts to the Suez Canal

    Science.gov (United States)

    Finkl, C.; Pelinovsky, E.

    2012-04-01

    Destructive tsunamis in the eastern Mediterranean and Red seas, induced by earthquakes and/or volcanic activity, pose potential hazards to docked seaport shipping and fixed harbor infrastructure as well as to in-transit international shipping within the Suez Canal. Potential vulnerabilities of the Suez Canal to possible tsunami impacts are reviewed by reference to geological, historical, archaeoseismological, and anecdotal data. Tsunami catalogues and databases compiled by earlier researchers are perused to estimate potential return periods for tsunami events that could affect directly the Suez Canal and its closely associated operational infrastructures. Analysis of these various records indicates a centurial return period, or multiples thereof, for long-wave repetition that could generally affect the Nile Delta. It is estimated that tsunami waves 2 m high would have a breaking length about 5 km down Canal whereas a 10 m wave break would occur about 1 km into the Canal. Should a tsunami strike the eastern flanks of the Nile Delta, it would damage Egypt's maritime infrastructure and multi-national commercial vessels and military ships then using the Canal.

  10. Do Earthquakes Shake Stock Markets?

    Science.gov (United States)

    Ferreira, Susana; Karali, Berna

    2015-01-01

    This paper examines how major earthquakes affected the returns and volatility of aggregate stock market indices in thirty-five financial markets over the last twenty years. Results show that global financial markets are resilient to shocks caused by earthquakes even if these are domestic. Our analysis reveals that, in a few instances, some macroeconomic variables and earthquake characteristics (gross domestic product per capita, trade openness, bilateral trade flows, earthquake magnitude, a tsunami indicator, distance to the epicenter, and number of fatalities) mediate the impact of earthquakes on stock market returns, resulting in a zero net effect. However, the influence of these variables is market-specific, indicating no systematic pattern across global capital markets. Results also demonstrate that stock market volatility is unaffected by earthquakes, except for Japan.

  11. Observations and Modeling of the 27 February 2010 Tsunami in Chile

    Science.gov (United States)

    Synolakis, C. E.; Fritz, H. M.; Petroff, C. M.; Catalan, P. A.; Cienfuegos, R.; Winckler, P.; Kalligeris, N.; Weiss, R.; Meneses, G.; Valderas-Bermejo, C.; Ebeling, C. W.; Papadopoulos, A.; Contreras, M.; Almar, R.; Dominguez, J. C.; Barrientos, S. E.

    2010-12-01

    On 27 February 2010, a magnitude Mw 8.8 earthquake occurred just off the coast of Chile, 100km N of Concepción, causing substantial damage and loss of life on Chile’s mainland and the Juan Fernandez archipelago. The tsunami accounts for 124 victims out of about 500 fatalities. Fortunately, ancestral knowledge from past tsunamis such as the giant 1960 event and tsunami education and evacuation exercises prompted most coastal residents to spontaneously evacuate to high ground after the earthquake. The majority of the tsunami victims were tourists staying overnight in low lying camp grounds along the coast. A multi-disciplinary ITST was deployed within days of the event to document flow depths, runup heights, inundation distances, sediment deposition, damage patterns at various scales, performance of the man-made infrastructure and impact on the natural environment per established protocols. The 3-25 March ITST covered an 800km stretch of coastline from Quintero to Mehuín in various subgroups the Pacific Islands of Santa María, Juan Fernández Archipelago, and Rapa Nui (Easter Island), while Mocha Island was surveyed 21-23 May, 2010. The collected survey data includes more than 400 tsunami runup and flow depth measurements. The tsunami impact peaked with a localized maximum runup of 29m on a coastal bluff at Constitución and 23 m on marine terraces on Mocha. A significant variation in tsunami impact was observed along Chile’s mainland both at local and regional scales. Inundation and damage also occurred several kilometers inland along rivers. Observations from the Chile tsunami are compared against the 2004 Indian Ocean tsunami. The tsunamigenic seafloor displacements were partially characterized based on coastal uplift measurements along a 100 km stretch of coastline between Caleta Chome and Punta Morguilla. More than 2 m vertical uplift were measured on Santa Maria Island. Coastal uplift measurements in Chile are compared with tectonic land level changes

  12. The SAFRR (Science Application for Risk Reduction) Tsunami Scenario

    Science.gov (United States)

    Ross, Stephanie L.; Jones, Lucile M.

    2013-01-01

    The Science Application for Risk Reduction (SAFRR) tsunami scenario depicts a hypothetical but plausible tsunami created by an earthquake offshore from the Alaska Peninsula and its impacts on the California coast. The tsunami scenario is a collaboration between the U.S. Geological Survey (USGS), the California Geological Survey (CGS), the California Governor’s Office of Emergency Services (Cal OES), the National Oceanic and Atmospheric Administration (NOAA), other Federal, State, County, and local agencies, private companies, and academic and other institutions. This document presents evidence for past tsunamis, the scientific basis for the source, likely inundation areas, current velocities in key ports and harbors, physical damage and repair costs, economic consequences, environmental and ecological impacts, social vulnerability, emergency management and evacuation challenges, and policy implications for California associated with this hypothetical tsunami. We also discuss ongoing mitigation efforts by the State of California and new communication products. The intended users are those who need to make mitigation decisions before future tsunamis, and those who will need to make rapid decisions during tsunami events. The results of the tsunami scenario will help managers understand the context and consequences of their decisions and how they may improve preparedness and response. An evaluation component will assess the effectiveness of the scenario process for target stakeholders in a separate report to improve similar efforts in the future.

  13. Can mine tremors be predicted? Observational studies of earthquake nucleation, triggering and rupture in South African mines

    CSIR Research Space (South Africa)

    Durrheim, RJ

    2012-05-01

    Full Text Available Earthquakes, and the tsunamis and landslides they trigger, pose a serious risk to people living close to plate boundaries, and a lesser but still significant risk to inhabitants of stable continental regions where destructive earthquakes are rare... of experiments that seek to identify reliable precursors of damaging seismic events. 1. Introduction Earthquakes, and the tsunamis and landslides they trigger, pose a serious risk to people living close to plate boundaries, and a lesser but still significant...

  14. The El Salvador and Philippines Tsunamis of August 2012: Insights from Sea Level Data Analysis and Numerical Modeling

    Science.gov (United States)

    Heidarzadeh, Mohammad; Satake, Kenji

    2014-12-01

    We studied two tsunamis from 2012, one generated by the El Salvador earthquake of 27 August ( Mw 7.3) and the other generated by the Philippines earthquake of 31 August ( Mw 7.6), using sea level data analysis and numerical modeling. For the El Salvador tsunami, the largest wave height was observed in Baltra, Galapagos Islands (71.1 cm) located about 1,400 km away from the source. The tsunami governing periods were around 9 and 19 min. Numerical modeling indicated that most of the tsunami energy was directed towards the Galapagos Islands, explaining the relatively large wave height there. For the Philippines tsunami, the maximum wave height of 30.5 cm was observed at Kushimoto in Japan located about 2,700 km away from the source. The tsunami governing periods were around 8, 12 and 29 min. Numerical modeling showed that a significant part of the far-field tsunami energy was directed towards the southern coast of Japan. Fourier and wavelet analyses as well as numerical modeling suggested that the dominant period of the first wave at stations normal to the fault strike is related to the fault width, while the period of the first wave at stations in the direction of fault strike is representative of the fault length.

  15. Real-time Inversion of Tsunami Source from GNSS Ground Deformation Observations and Tide Gauges.

    Science.gov (United States)

    Arcas, D.; Wei, Y.

    2017-12-01

    Over the last decade, the NOAA Center for Tsunami Research (NCTR) has developed an inversion technique to constrain tsunami sources based on the use of Green's functions in combination with data reported by NOAA's Deep-ocean Assessment and Reporting of Tsunamis (DART®) systems. The system has consistently proven effective in providing highly accurate tsunami forecasts of wave amplitude throughout an entire basin. However, improvement is necessary in two critical areas: reduction of data latency for near-field tsunami predictions and reduction of maintenance cost of the network. Two types of sensors have been proposed as supplementary to the existing network of DART®systems: Global Navigation Satellite System (GNSS) stations and coastal tide gauges. The use GNSS stations to provide autonomous geo-spatial positioning at specific sites during an earthquake has been proposed in recent years to supplement the DART® array in tsunami source inversion. GNSS technology has the potential to provide substantial contributions in the two critical areas of DART® technology where improvement is most necessary. The present study uses GNSS ground displacement observations of the 2011 Tohoku-Oki earthquake in combination with NCTR operational database of Green's functions, to produce a rapid estimate of tsunami source based on GNSS observations alone. The solution is then compared with that obtained via DART® data inversion and the difficulties in obtaining an accurate GNSS-based solution are underlined. The study also identifies the set of conditions required for source inversion from coastal tide-gauges using the degree of nonlinearity of the signal as a primary criteria. We then proceed to identify the conditions and scenarios under which a particular gage could be used to invert a tsunami source.

  16. Lessons from the Tōhoku tsunami: A model for island avifauna conservation prioritization

    Science.gov (United States)

    Reynolds, Michelle H.; Berkowitz, Paul; Klavitter, John; Courtot, Karen

    2017-01-01

    Earthquake-generated tsunamis threaten coastal areas and low-lying islands with sudden flooding. Although human hazards and infrastructure damage have been well documented for tsunamis in recent decades, the effects on wildlife communities rarely have been quantified. We describe a tsunami that hit the world's largest remaining tropical seabird rookery and estimate the effects of sudden flooding on 23 bird species nesting on Pacific islands more than 3,800 km from the epicenter. We used global positioning systems, tide gauge data, and satellite imagery to quantify characteristics of the Tōhoku earthquake-generated tsunami (11 March 2011) and its inundation extent across four Hawaiian Islands. We estimated short-term effects of sudden flooding to bird communities using spatially explicit data from Midway Atoll and Laysan Island, Hawai'i. We describe variation in species vulnerability based on breeding phenology, nesting habitat, and life history traits. The tsunami inundated 21%–100% of each island's area at Midway Atoll and Laysan Island. Procellariformes (albatrosses and petrels) chick and egg losses exceeded 258,500 at Midway Atoll while albatross chick losses at Laysan Island exceeded 21,400. The tsunami struck at night and during the peak of nesting for 14 colonial seabird species. Strongly philopatric Procellariformes were vulnerable to the tsunami. Nonmigratory, endemic, endangered Laysan Teal (Anas laysanensis) were sensitive to ecosystem effects such as habitat changes and carcass-initiated epizootics of avian botulism, and its populations declined approximately 40% on both atolls post-tsunami. Catastrophic flooding of Pacific islands occurs periodically not only from tsunamis, but also from storm surge and rainfall; with sea-level rise, the frequency of sudden flooding events will likely increase. As invasive predators occupy habitat on higher elevation Hawaiian Islands and globally important avian populations are concentrated on low-lying islands

  17. Modeling for the SAFRR Tsunami Scenario-generation, propagation, inundation, and currents in ports and harbors: Chapter D in The SAFRR (Science Application for Risk Reduction) Tsunami Scenario

    Science.gov (United States)

    ,

    2013-01-01

    This U.S. Geological Survey (USGS) Open-File report presents a compilation of tsunami modeling studies for the Science Application for Risk Reduction (SAFRR) tsunami scenario. These modeling studies are based on an earthquake source specified by the SAFRR tsunami source working group (Kirby and others, 2013). The modeling studies in this report are organized into three groups. The first group relates to tsunami generation. The effects that source discretization and horizontal displacement have on tsunami initial conditions are examined in section 1 (Whitmore and others). In section 2 (Ryan and others), dynamic earthquake rupture models are explored in modeling tsunami generation. These models calculate slip distribution and vertical displacement of the seafloor as a result of realistic fault friction, physical properties of rocks surrounding the fault, and dynamic stresses resolved on the fault. The second group of papers relates to tsunami propagation and inundation modeling. Section 3 (Thio) presents a modeling study for the entire California coast that includes runup and inundation modeling where there is significant exposure and estimates of maximum velocity and momentum flux at the shoreline. In section 4 (Borrero and others), modeling of tsunami propagation and high-resolution inundation of critical locations in southern California is performed using the National Oceanic and Atmospheric Administration’s (NOAA) Method of Splitting Tsunami (MOST) model and NOAA’s Community Model Interface for Tsunamis (ComMIT) modeling tool. Adjustments to the inundation line owing to fine-scale structures such as levees are described in section 5 (Wilson). The third group of papers relates to modeling of hydrodynamics in ports and harbors. Section 6 (Nicolsky and Suleimani) presents results of the model used at the Alaska Earthquake Information Center for the Ports of Los Angeles and Long Beach, as well as synthetic time series of the modeled tsunami for other selected

  18. New Approaches to Tsunami Hazard Mitigation Demonstrated in Oregon

    Science.gov (United States)

    Priest, G. R.; Rizzo, A.; Madin, I.; Lyles Smith, R.; Stimely, L.

    2012-12-01

    methods were: (1) door-to-door (person-to-person) education, (2) evacuation drills, (3) outreach to K-12 schools, (4) media events, and (5) workshops targeted to key audiences (lodging facilities, teachers, and local officials). Community organizers were hired to apply these five methods to clusters of small communities, measuring performance by before and after polling. Organizers were encouraged to approach the top priority, person-to-person education, by developing Community Emergency Response Teams (CERT) or CERT-like organizations in each community, thereby leaving behind a functioning volunteer-based group that will continue the outreach program and build long term resiliency. One of the most effective person-to-person educational tools was the Map Your Neighborhood program that brings people together so they can sketch the basic layout of their neighborhoods to depict key earthquake and tsunami hazards and mitigation solutions. The various person-to-person volunteer efforts and supporting outreach activities are knitting communities together and creating a permanent culture of tsunami and earthquake preparedness. All major Oregon coastal population centers will have been covered by this intensive outreach program by ~2014.

  19. Tsunami simulation using submarine displacement calculated from simulation of ground motion due to seismic source model

    Science.gov (United States)

    Akiyama, S.; Kawaji, K.; Fujihara, S.

    2013-12-01

    Since fault fracturing due to an earthquake can simultaneously cause ground motion and tsunami, it is appropriate to evaluate the ground motion and the tsunami by single fault model. However, several source models are used independently in the ground motion simulation or the tsunami simulation, because of difficulty in evaluating both phenomena simultaneously. Many source models for the 2011 off the Pacific coast of Tohoku Earthquake are proposed from the inversion analyses of seismic observations or from those of tsunami observations. Most of these models show the similar features, which large amount of slip is located at the shallower part of fault area near the Japan Trench. This indicates that the ground motion and the tsunami can be evaluated by the single source model. Therefore, we examine the possibility of the tsunami prediction, using the fault model estimated from seismic observation records. In this study, we try to carry out the tsunami simulation using the displacement field of oceanic crustal movements, which is calculated from the ground motion simulation of the 2011 off the Pacific coast of Tohoku Earthquake. We use two fault models by Yoshida et al. (2011), which are based on both the teleseismic body wave and on the strong ground motion records. Although there is the common feature in those fault models, the amount of slip near the Japan trench is lager in the fault model from the strong ground motion records than in that from the teleseismic body wave. First, the large-scale ground motion simulations applying those fault models used by the voxel type finite element method are performed for the whole eastern Japan. The synthetic waveforms computed from the simulations are generally consistent with the observation records of K-NET (Kinoshita (1998)) and KiK-net stations (Aoi et al. (2000)), deployed by the National Research Institute for Earth Science and Disaster Prevention (NIED). Next, the tsunami simulations are performed by the finite

  20. SAFRR Tsunami Scenarios and USGS-NTHMP Collaboration

    Science.gov (United States)

    Ross, S.; Wood, N. J.; Cox, D. A.; Jones, L.; Cheung, K. F.; Chock, G.; Gately, K.; Jones, J. L.; Lynett, P. J.; Miller, K.; Nicolsky, D.; Richards, K.; Wein, A. M.; Wilson, R. I.

    2015-12-01

    Hazard scenarios provide emergency managers and others with information to help them prepare for future disasters. The SAFRR Tsunami Scenario, published in 2013, modeled a hypothetical but plausible tsunami, created by an Mw9.1 earthquake occurring offshore from the Alaskan peninsula, and its impacts on the California coast. It presented the modeled inundation areas, current velocities in key ports and harbors, physical damage and repair costs, economic consequences, environmental impacts, social vulnerability, emergency management, and policy implications for California associated with the scenario tsunami. The intended users were those responsible for making mitigation decisions before and those who need to make rapid decisions during future tsunamis. It provided the basis for many exercises involving, among others, NOAA, the State of Washington, several counties in California, and the National Institutes of Health. The scenario led to improvements in the warning protocol for southern California and highlighted issues that led to ongoing work on harbor and marina safety. Building on the lessons learned in the SAFRR Tsunami Scenario, another tsunami scenario is being developed with impacts to Hawaii and to the source region in Alaska, focusing on the evacuation issues of remote communities with primarily shore parallel roads, and also on the effects of port closures. Community exposure studies in Hawaii (Ratliff et al., USGS-SIR, 2015) provided background for selecting these foci. One complicated and important aspect of any hazard scenario is defining the source event. The USGS is building collaborations with the National Tsunami Hazard Mitigation Program (NTHMP) to consider issues involved in developing a standardized set of tsunami sources to support hazard mitigation work. Other key USGS-NTHMP collaborations involve population vulnerability and evacuation modeling.

  1. Geological evidence of recurrent great Kanto earthquakes at the Miura Peninsula, Japan

    Science.gov (United States)

    Shimazaki, K.; Kim, H. Y.; Chiba, T.; Satake, K.

    2011-12-01

    The Tokyo metropolitan area's well-documented earthquake history is dominated by the 1703 and 1923 great Kanto earthquakes produced by slip on the boundary between the subducting Philippine Sea plate and the overlying plate. Both earthquakes caused ˜1.5 m of uplift at the Miura Peninsula directly above the inferred fault rupture, and both were followed by tsunamis with heights of ˜5 m. We examined cores ˜2 m long from 8 tidal flat sites at the head of a small bay on the peninsula. The cores penetrated two to four layers of shelly gravel, as much as 0.5 m thick, with abundant shell fragments and mud clasts. The presence of gravel indicates strong tractive currents. Muddy bay deposits that bound the gravel layers show vertical changes in grain size and diatom assemblages consistent with abrupt shoaling at the times of the currents. The changes may further suggest gradual deepening of the bay during the intervals between the strong currents. We infer, based on 137Cs, 14C, and 210Pb dating, that the top two shelly gravel layers represent tsunamis associated with the 1703 and 1923 great Kanto earthquakes, and that the third layer was deposited by a tsunami during an earlier earthquake. The age range of this layer, AD 1060-1400, includes the time of an earthquake that occurred in 1293 according to a historical document. If so, the recurrence interval before the 1703 earthquake was almost twice as long as the interval between the 1703 and 1923 earthquakes.

  2. SAFRR (Science Application for Risk Reduction) Tsunami Scenario--Executive Summary and Introduction: Chapter A in The SAFRR (Science Application for Risk Reduction) Tsunami Scenario

    Science.gov (United States)

    Ross, Stephanie L.; Jones, Lucile M.; Miller, Kevin H.; Porter, Keith A.; Wein, Anne; Wilson, Rick I.; Bahng, Bohyun; Barberopoulou, Aggeliki; Borrero, Jose C.; Brosnan, Deborah M.; Bwarie, John T.; Geist, Eric L.; Johnson, Laurie A.; Kirby, Stephen H.; Knight, William R.; Long, Kate; Lynett, Patrick; Mortensen, Carl E.; Nicolsky, Dmitry J.; Perry, Suzanne C.; Plumlee, Geoffrey S.; Real, Charles R.; Ryan, Kenneth; Suleimani, Elena; Thio, Hong Kie; Titov, Vasily V.; Whitmore, Paul M.; Wood, Nathan J.

    2013-01-01

    The Science Application for Risk Reduction (SAFRR) tsunami scenario depicts a hypothetical but plausible tsunami created by an earthquake offshore from the Alaska Peninsula and its impacts on the California coast. The tsunami scenario is a collaboration between the U.S. Geological Survey (USGS), the California Geological Survey, the California Governor’s Office of Emergency Services (Cal OES), the National Oceanic and Atmospheric Administration (NOAA), other Federal, State, County, and local agencies, private companies, and academic and other institutions. This document presents evidence for past tsunamis, the scientific basis for the source, likely inundation areas, current velocities in key ports and harbors, physical damage and repair costs, economic consequences, environmental and ecological impacts, social vulnerability, emergency management and evacuation challenges, and policy implications for California associated with this hypothetical tsunami. We also discuss ongoing mitigation efforts by the State of California and new communication products. The intended users are those who need to make mitigation decisions before future tsunamis, and those who will need to make rapid decisions during tsunami events. The results of the tsunami scenario will help managers understand the context and consequences of their decisions and how they may improve preparedness and response. An evaluation component will assess the effectiveness of the scenario process for target stakeholders in a separate report to improve similar efforts in the future.

  3. Rescue, Archival and Discovery of Tsunami Events on Marigrams

    Science.gov (United States)

    Eble, M. C.; Wright, L. M.; Stroker, K. J.; Sweeney, A.; Lancaster, M.

    2017-12-01

    The Big Earth Data Initiative made possible the reformatting of paper marigram records on which were recorded measurements of the 1946, 1952, 1960, and 1964 tsunamis generated in the Pacific Ocean. Data contained within each record were determined to be invaluable for tsunami researchers and operational agencies with a responsibility for issuing warnings during a tsunami event. All marigrams were carefully digitized and metadata were generated to form numerical datasets in order to provide the tsunami and other research and application-driven communities with quality data. Data were then packaged as CF-compliant netCDF datafiles and submitted to the NOAA Centers for Environmental Information for long-term stewardship, archival, and public discovery of both original scanned images and data in digital netCDF and CSC formats. The PNG plots of each time series were generated and included with data packages to provide a visual representation of the numerical data sets. ISO-compliant metadata were compiled for the collection at the event level and individual DOIs were minted for each of the four events included in this project. The procedure followed to reformat each record in this four-event subset of the larger NCEI scanned marigram inventory is presented and discussed. The practical use of these data is presented to highlight that even infrequent measurements of tsunamis hold information that may potentially help constrain earthquake rupture area, provide estimates of earthquake co-seismic slip distribution, identify subsidence or uplift, and significantly increase the holdings of situ data available for tsunami model validation. These same data may also prove valuable to the broader global tide community for validation and further development of tide models and for investigation into the stability of tidal harmonic constants. Data reformatted as part of this project are PARR compliant and meet the requirements for Data Management, Discoverability, Accessibility

  4. THE RESPONSE OF MONTEREY BAY TO THE 2010 CHILEAN EARTHQUAKE

    Directory of Open Access Journals (Sweden)

    Laurence C. Breaker

    2011-01-01

    Full Text Available The primary frequencies contained in the arrival sequence produced by the tsunami from the Chilean earthquake of 2010 in Monterey Bay were extracted to determine the seiche modes that were produced. Singular Spectrum Analysis (SSA and Ensemble Empirical Mode Decomposition (EEMD were employed to extract the primary frequencies of interest. The wave train from the Chilean tsunami lasted for at least four days due to multipath arrivals that may not have included reflections from outside the bay but most likely did include secondary undulations, and energy trapping in the form of edge waves, inside the bay. The SSA decomposition resolved oscillations with periods of 52-57, 34-35, 26-27, and 21-22 minutes, all frequencies that have been predicted and/or observed in previous studies. The EEMD decomposition detected oscillations with periods of 50-55 and 21-22 minutes. Periods in the range of 50-57 minutes varied due to measurement uncertainties but almost certainly correspond to the first longitudinal mode of oscillation for Monterey Bay, periods of 34-35 minutes correspond to the first transverse mode of oscillation that assumes a nodal line across the entrance of the bay, a period of 26- 27 minutes, although previously observed, may not represent a fundamental oscillation, and a period of 21-22 minutes has been predicted and observed previously. A period of ~37 minutes, close to the period of 34-35 minutes, was generated by the Great Alaskan Earthquake of 1964 in Monterey Bay and most likely represents the same mode of oscillation. The tsunamis associated with the Great Alaskan Earthquake and the Chilean Earthquake both entered Monterey Bay but initially arrived outside the bay from opposite directions. Unlike the Great Alaskan Earthquake, however, which excited only one resonant mode inside the bay, the Chilean Earthquake excited several modes suggesting that the asymmetric shape of the entrance to Monterey Bay was an important factor and that the

  5. Scenario based tsunami wave height estimation towards hazard evaluation for the Hellenic coastline and examples of extreme inundation zones in South Aegean

    Science.gov (United States)

    Melis, Nikolaos S.; Barberopoulou, Aggeliki; Frentzos, Elias; Krassanakis, Vassilios

    2016-04-01

    A scenario based methodology for tsunami hazard assessment is used, by incorporating earthquake sources with the potential to produce extreme tsunamis (measured through their capacity to cause maximum wave height and inundation extent). In the present study we follow a two phase approach. In the first phase, existing earthquake hazard zoning in the greater Aegean region is used to derive representative maximum expected earthquake magnitude events, with realistic seismotectonic source characteristics, and of greatest tsunamigenic potential within each zone. By stacking the scenario produced maximum wave heights a global maximum map is constructed for the entire Hellenic coastline, corresponding to all expected extreme offshore earthquake sources. Further evaluation of the produced coastline categories based on the maximum expected wave heights emphasizes the tsunami hazard in selected coastal zones with important functions (i.e. touristic crowded zones, industrial zones, airports, power plants etc). Owing to its proximity to the Hellenic Arc, many urban centres and being a popular tourist destination, Crete Island and the South Aegean region are given a top priority to define extreme inundation zoning. In the second phase, a set of four large coastal cities (Kalamata, Chania, Heraklion and Rethymno), important for tsunami hazard, due i.e. to the crowded beaches during the summer season or industrial facilities, are explored towards preparedness and resilience for tsunami hazard in Greece. To simulate tsunamis in the Aegean region (generation, propagation and runup) the MOST - ComMIT NOAA code was used. High resolution DEMs for bathymetry and topography were joined via an interface, specifically developed for the inundation maps in this study and with similar products in mind. For the examples explored in the present study, we used 5m resolution for the topography and 30m resolution for the bathymetry, respectively. Although this study can be considered as

  6. Village Level Tsunami Threat Maps for Tamil Nadu, SE Coast of India: Numerical Modeling Technique

    Science.gov (United States)

    MP, J.; Kulangara Madham Subrahmanian, D.; V, R. M.

    2014-12-01

    The Indian Ocean tsunami (IOT) devastated several countries of North Indian Ocean. India is one of the worst affected countries after Indonesia and Sri Lanka. In India, Tamil Nadu suffered maximum with fatalities exceeding 8,000 people. Historical records show that tsunami has invaded the shores of Tamil Nadu in the past and has made people realize that the tsunami threat looms over Tamil Nadu and it is necessary to evolve strategies for tsunami threat management. The IOT has brought to light that tsunami inundation and runup varied within short distances and for the disaster management for tsunami, large scale maps showing areas that are likely to be affected by future tsunami are identified. Therefore threat assessment for six villages including Mamallapuram (also called Mahabalipuram) which is famous for its rock-cut temples, from the northern part of Tamil Nadu state of India has been carried out and threat maps categorizing the coast into areas of different degree of threat are prepared. The threat was assessed by numerical modeling using TUNAMI N2 code considering different tsunamigenic sources along the Andaman - Sumatra trench. While GEBCO and C-Map data was used for bathymetry and for land elevation data was generated by RTK - GPS survey for a distance of 1 km from shore and SRTM for the inland areas. The model results show that in addition to the Sumatra source which generated the IOT in 2004, earthquakes originating in Car Nicobar and North Andaman can inflict more damage. The North Andaman source can generate a massive tsunami and an earthquake of magnitude more than Mw 9 can not only affect Tamil Nadu but also entire south east coast of India. The runup water level is used to demarcate the tsunami threat zones in the villages using GIS.

  7. Global Tsunami Database: Adding Geologic Deposits, Proxies, and Tools

    Science.gov (United States)

    Brocko, V. R.; Varner, J.

    2007-12-01

    display data from the Oracle database (selection forms, Web Map Services, and Web Feature Services). In addition, the historic tsunami archive (along with related earthquakes and volcanic eruptions) is available in KML (Keyhole Markup Language) format for use with Google Earth and similar geo-viewers.

  8. Applying the natural disasters vulnerability evaluation model to the March 2011 north-east Japan earthquake and tsunami.

    Science.gov (United States)

    Ruiz Estrada, Mario Arturo; Yap, Su Fei; Park, Donghyun

    2014-07-01

    Natural hazards have a potentially large impact on economic growth, but measuring their economic impact is subject to a great deal of uncertainty. The central objective of this paper is to demonstrate a model--the natural disasters vulnerability evaluation (NDVE) model--that can be used to evaluate the impact of natural hazards on gross national product growth. The model is based on five basic indicators-natural hazards growth rates (αi), the national natural hazards vulnerability rate (ΩT), the natural disaster devastation magnitude rate (Π), the economic desgrowth rate (i.e. shrinkage of the economy) (δ), and the NHV surface. In addition, we apply the NDVE model to the north-east Japan earthquake and tsunami of March 2011 to evaluate its impact on the Japanese economy. © 2014 The Author(s). Disasters © Overseas Development Institute, 2014.

  9. TSUNAMIGENIC SOURCE MECHANISM AND EFFICIENCY OF THE MARCH 11, 2011 SANRIKU EARTHQUAKE IN JAPAN

    Directory of Open Access Journals (Sweden)

    George Pararas-Carayannis

    2011-01-01

    Full Text Available The great Tohoku earthquake of March 11, 2011 generated a very destructive and anomalously high tsunami. To understand its source mechanism, an examination was undertaken of the seismotectonics of the region and of the earthquake’ focal mechanism, energy release, rupture patterns and spatial and temporal sequencing and clustering of major aftershocks. It was determined that the great tsunami resulted from a combination of crustal deformations of the ocean floor due to up-thrust tectonic motions, augmented by additional uplift due to the quake’s slow and long rupturing process, as well as to large coseismic lateral movements which compressed and deformed the compacted sediments along the accretionary prism of the overriding plane. The deformation occurred randomly and non-uniformly along parallel normal faults and along oblique, en-echelon faults to the earthquake’s overall rupture direction – the latter failing in a sequential bookshelf manner with variable slip angles. As the 1992 Nicaragua and the 2004 Sumatra earthquakes demonstrated, such bookshelf failures of sedimentary layers could contribute to anomalously high tsunamis. As with the 1896 tsunami, additional ocean floor deformation and uplift of the sediments was responsible for the higher waves generated by the 2011 earthquake. The efficiency of tsunami generation was greater along the shallow eastern segment of the fault off the Miyagi Prefecture where most of the energy release of the earthquake and the deformations occurred, while the segment off the Ibaraki Prefecture – where the rupture process was rapid – released less seismic energy, resulted in less compaction and deformation of sedimentary layers and thus to a tsunami of lesser offshore height. The greater tsunamigenic efficiency of the 2011 earthquake and high degree of the tsunami’s destructiveness along Honshu’s coastlines resulted from vertical crustal displacements of more than 10 meters due to up

  10. Probabilistic Tsunami Hazard Assessment: the Seaside, Oregon Pilot Study

    Science.gov (United States)

    Gonzalez, F. I.; Geist, E. L.; Synolakis, C.; Titov, V. V.

    2004-12-01

    A pilot study of Seaside, Oregon is underway, to develop methodologies for probabilistic tsunami hazard assessments that can be incorporated into Flood Insurance Rate Maps (FIRMs) developed by FEMA's National Flood Insurance Program (NFIP). Current NFIP guidelines for tsunami hazard assessment rely on the science, technology and methodologies developed in the 1970s; although generally regarded as groundbreaking and state-of-the-art for its time, this approach is now superseded by modern methods that reflect substantial advances in tsunami research achieved in the last two decades. In particular, post-1990 technical advances include: improvements in tsunami source specification; improved tsunami inundation models; better computational grids by virtue of improved bathymetric and topographic databases; a larger database of long-term paleoseismic and paleotsunami records and short-term, historical earthquake and tsunami records that can be exploited to develop improved probabilistic methodologies; better understanding of earthquake recurrence and probability models. The NOAA-led U.S. National Tsunami Hazard Mitigation Program (NTHMP), in partnership with FEMA, USGS, NSF and Emergency Management and Geotechnical agencies of the five Pacific States, incorporates these advances into site-specific tsunami hazard assessments for coastal communities in Alaska, California, Hawaii, Oregon and Washington. NTHMP hazard assessment efforts currently focus on developing deterministic, "credible worst-case" scenarios that provide valuable guidance for hazard mitigation and emergency management. The NFIP focus, on the other hand, is on actuarial needs that require probabilistic hazard assessments such as those that characterize 100- and 500-year flooding events. There are clearly overlaps in NFIP and NTHMP objectives. NTHMP worst-case scenario assessments that include an estimated probability of occurrence could benefit the NFIP; NFIP probabilistic assessments of 100- and 500-yr

  11. The threat of silent earthquakes

    Science.gov (United States)

    Cervelli, Peter

    2004-01-01

    Not all earthquakes shake the ground. The so-called silent types are forcing scientists to rethink their understanding of the way quake-prone faults behave. In rare instances, silent earthquakes that occur along the flakes of seaside volcanoes may cascade into monstrous landslides that crash into the sea and trigger towering tsunamis. Silent earthquakes that take place within fault zones created by one tectonic plate diving under another may increase the chance of ground-shaking shocks. In other locations, however, silent slip may decrease the likelihood of destructive quakes, because they release stress along faults that might otherwise seem ready to snap.

  12. American Samoa Initial Technical Assessment Report

    Energy Technology Data Exchange (ETDEWEB)

    Busche, S.; Conrad, M.; Funk, K.; Kandt, A.; McNutt, P.

    2011-09-01

    This document is an initial energy assessment for American Samoa, the first of many steps in developing a comprehensive energy strategy. On March 1, 2010, Assistant Secretary of the Interior Tony Babauta invited governors and their staff from the Interior Insular Areas to meet with senior principals at the National Renewable Energy Laboratory (NREL). Meeting discussions focused on ways to improve energy efficiency and increase the deployment of renewable energy technologies in the U.S. Pacific Territories. In attendance were Governors Felix Camacho (Guam), Benigno Fitial (Commonwealth of the Northern Mariana Islands), and Togiola Tulafono, (American Samoa). This meeting brought together major stakeholders to learn and understand the importance of developing a comprehensive strategic plan for implementing energy efficiency measures and renewable energy technologies. For several decades, dependence on fossil fuels and the burden of high oil prices have been a major concern but never more at the forefront as today. With unstable oil prices, the volatility of fuel supply and the economic instability in American Samoa, energy issues are a high priority. In short, energy security is critical to American Samoa's future economic development and sustainability. Under an interagency agreement, funded by the Department of Interior's Office of Insular Affairs, NREL was tasked to deliver technical assistance to the islands of American Samoa. Technical assistance included conducting an initial technical assessment to define energy consumption and production data, establish an energy consumption baseline, and assist with the development of a strategic plan. The assessment and strategic plan will be used to assist with the transition to a cleaner energy economy. NREL provided an interdisciplinary team to cover each relevant technical area for the initial energy assessments. Experts in the following disciplines traveled to American Samoa for on-island site assessments: (1

  13. The Indian Ocean disaster: Tsunami physics and early warning dilemmas

    Science.gov (United States)

    Lomnitz, Cinna; Nilsen-Hofseth, Sara

    Understanding the physics of tsunamis may save lives, especially near the epicenter of a large earthquake where the danger is highest and early warning is least likely to be effective.Normal modes of Earth are standing waves of the Love (toroidal) or the Rayleigh (spheroidal) variety. The Indian Ocean tsunami may have been partly or wholly caused by low-order spheroidal modes of the Earth such as 0S2, 0S3, and 0S4, that may have excited a waveguide—a layer that confines and guides a propagating wave—in the ocean.

  14. A Preliminary Tsunami Vulnerability Analysis for Yenikapi Region in Istanbul

    Science.gov (United States)

    Ceren Cankaya, Zeynep; Suzen, Lutfi; Cevdet Yalciner, Ahmet; Kolat, Cagil; Aytore, Betul; Zaytsev, Andrey

    2015-04-01

    One of the main requirements during post disaster recovery operations is to maintain proper transportation and fluent communication at the disaster areas. Ports and harbors are the main transportation hubs which must work with proper performance at all times especially after the disasters. Resilience of coastal utilities after earthquakes and tsunamis have major importance for efficient and proper rescue and recovery operations soon after the disasters. Istanbul is a mega city with its various coastal utilities located at the north coast of the Sea of Marmara. At Yenikapi region of Istanbul, there are critical coastal utilities and vulnerable coastal structures and critical activities occur daily. Fishery ports, commercial ports, small craft harbors, passenger terminals of intercity maritime transportation, water front commercial and/or recreational structures are some of the examples of coastal utilization which are vulnerable against marine disasters. Therefore their vulnerability under tsunami or any other marine hazard to Yenikapi region of Istanbul is an important issue. In this study, a methodology of vulnerability analysis under tsunami attack is proposed with the applications to Yenikapi region. In the study, high resolution (1m) GIS database of Istanbul Metropolitan Municipality (IMM) is used and analyzed by using GIS implementation. The bathymetry and topography database and the vector dataset containing all buildings/structures/infrastructures in the study area are obtained for tsunami numerical modeling for the study area. GIS based tsunami vulnerability assessment is conducted by applying the Multi-criteria Decision Making Analysis (MCDA). The tsunami parameters from deterministically defined worst case scenarios are computed from the simulations using tsunami numerical model NAMI DANCE. The vulnerability parameters in the region due to two different classifications i) vulnerability of buildings/structures and ii) vulnerability of (human) evacuation

  15. Probability-Based Design Criteria of the ASCE 7 Tsunami Loads and Effects Provisions (Invited)

    Science.gov (United States)

    Chock, G.

    2013-12-01

    Mitigation of tsunami risk requires a combination of emergency preparedness for evacuation in addition to providing structural resilience of critical facilities, infrastructure, and key resources necessary for immediate response and economic and social recovery. Critical facilities would include emergency response, medical, tsunami refuges and shelters, ports and harbors, lifelines, transportation, telecommunications, power, financial institutions, and major industrial/commercial facilities. The Tsunami Loads and Effects Subcommittee of the ASCE/SEI 7 Standards Committee is developing a proposed new Chapter 6 - Tsunami Loads and Effects for the 2016 edition of the ASCE 7 Standard. ASCE 7 provides the minimum design loads and requirements for structures subject to building codes such as the International Building Code utilized in the USA. In this paper we will provide a review emphasizing the intent of these new code provisions and explain the design methodology. The ASCE 7 provisions for Tsunami Loads and Effects enables a set of analysis and design methodologies that are consistent with performance-based engineering based on probabilistic criteria. . The ASCE 7 Tsunami Loads and Effects chapter will be initially applicable only to the states of Alaska, Washington, Oregon, California, and Hawaii. Ground shaking effects and subsidence from a preceding local offshore Maximum Considered Earthquake will also be considered prior to tsunami arrival for Alaska and states in the Pacific Northwest regions governed by nearby offshore subduction earthquakes. For national tsunami design provisions to achieve a consistent reliability standard of structural performance for community resilience, a new generation of tsunami inundation hazard maps for design is required. The lesson of recent tsunami is that historical records alone do not provide a sufficient measure of the potential heights of future tsunamis. Engineering design must consider the occurrence of events greater than

  16. Model validation and error estimation of tsunami runup using high resolution data in Sadeng Port, Gunungkidul, Yogyakarta

    Science.gov (United States)

    Basith, Abdul; Prakoso, Yudhono; Kongko, Widjo

    2017-07-01

    A tsunami model using high resolution geometric data is indispensable in efforts to tsunami mitigation, especially in tsunami prone areas. It is one of the factors that affect the accuracy results of numerical modeling of tsunami. Sadeng Port is a new infrastructure in the Southern Coast of Java which could potentially hit by massive tsunami from seismic gap. This paper discusses validation and error estimation of tsunami model created using high resolution geometric data in Sadeng Port. Tsunami model validation uses the height wave of Tsunami Pangandaran 2006 recorded by Tide Gauge of Sadeng. Tsunami model will be used to accommodate the tsunami numerical modeling involves the parameters of earthquake-tsunami which is derived from the seismic gap. The validation results using t-test (student) shows that the height of the tsunami modeling results and observation in Tide Gauge of Sadeng are considered statistically equal at 95% confidence level and the value of the RMSE and NRMSE are 0.428 m and 22.12%, while the differences of tsunami wave travel time is 12 minutes.

  17. Analyses of surface motions caused by the magnitude 9.0 2004 Sumatra earthquake

    DEFF Research Database (Denmark)

    Khan, Shfaqat Abbas; Gudmundsson, Ó.

    The Sumatra, Indonesia, earthquake on December 26th was one of the most devastating earthquakes in history. With a magnitude of Mw = 9.0 it is the forth largest earthquake recorded since 1900. It occurred about one hundred kilometers off the west coast of northern Sumatra, where the relatively thin...... of years. The result was a devastating tsunami hitting coastlines across the Indian Ocean killing more than 225,000 people in Sri Lanka, India, Indonesia, Thailand and Malaysia. An earthquake of this magnitude is expected to involve a displacement on the fault on the order of 10 meters. But, what...... was the actual amplitude of the surface motions that triggered the tsunami? This can be constrained using the amplitudes of elastic waves radiated from the earthquake, or by direct measurements of deformation. Here we present estimates of the deformation based on continuous Global Positioning System (GPS...

  18. The effect analysis of 1741 Oshima-Oshima tsunami in the West Coast of Japan to Korea

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Minkyu; Rhee, Hyunme; Choi, Inkil [Korea Atomic Energy Research institute, Daejeon (Korea, Republic of)

    2013-05-15

    It is very difficult to determine and assessment for tsunami hazard. For determining a tsunami risk for NPP site, a development of tsunami hazard is one of the most important. Through the tsunami hazard analysis, a tsunami return period can be determined. For the performing a tsunami hazard analysis, empirical method and numerical method should be needed. Kim et al, already developed tsunami hazard for east coast of Korea for the calculation of tsunami risk of nuclear power plant. In the case of tsunami hazard analysis, a development of tsunami catalog should be performed. In the previous research of Kim et al, the maximum wave height was assumed by the author's decision based on historical record in the annals of Chosun dynasty for evaluating the tsunami catalog. Therefore, in this study, a literature survey was performed for a quantitative measure of historical tsunami record transform to qualitative tsunami wave height for the evaluation of tsunami catalog. In this study, the 1741 tsunami was determined by using a literature review for the evaluation of tsunami hazard. The 1741 tsunami reveals a same tsunami between the historical records in Korea and Japan. The tsunami source of 1741 tsunami was not an earthquake and volcanic. Using the numerical analysis, the wave height of 1741 tsunami can be determined qualitatively.

  19. The effect analysis of 1741 Oshima-Oshima tsunami in the West Coast of Japan to Korea

    International Nuclear Information System (INIS)

    Kim, Minkyu; Rhee, Hyunme; Choi, Inkil

    2013-01-01

    It is very difficult to determine and assessment for tsunami hazard. For determining a tsunami risk for NPP site, a development of tsunami hazard is one of the most important. Through the tsunami hazard analysis, a tsunami return period can be determined. For the performing a tsunami hazard analysis, empirical method and numerical method should be needed. Kim et al, already developed tsunami hazard for east coast of Korea for the calculation of tsunami risk of nuclear power plant. In the case of tsunami hazard analysis, a development of tsunami catalog should be performed. In the previous research of Kim et al, the maximum wave height was assumed by the author's decision based on historical record in the annals of Chosun dynasty for evaluating the tsunami catalog. Therefore, in this study, a literature survey was performed for a quantitative measure of historical tsunami record transform to qualitative tsunami wave height for the evaluation of tsunami catalog. In this study, the 1741 tsunami was determined by using a literature review for the evaluation of tsunami hazard. The 1741 tsunami reveals a same tsunami between the historical records in Korea and Japan. The tsunami source of 1741 tsunami was not an earthquake and volcanic. Using the numerical analysis, the wave height of 1741 tsunami can be determined qualitatively

  20. Scedosporium aurantiacum brain abscess after near-drowning in a survivor of a tsunami in Japan.

    Science.gov (United States)

    Nakamura, Yutaka; Suzuki, Naomi; Nakajima, Yoshio; Utsumi, Yu; Murata, Okinori; Nagashima, Hiromi; Saito, Heisuke; Sasaki, Nobuhito; Fujimura, Itaru; Ogino, Yoshinobu; Kato, Kanako; Terayama, Yasuo; Miyamoto, Shinya; Yarita, Kyoko; Kamei, Katsuhiko; Nakadate, Toshihide; Endo, Shigeatsu; Shibuya, Kazutoshi; Yamauchi, Kohei

    2013-12-01

    Many victims of the tsunami that occurred following the Great East Japan Earthquake on March 11, 2011 developed systemic disorders owing to aspiration pneumonia. Herein, we report a case of tsunami lung wherein Scedosporium aurantiacum was detected in the respiratory tract. A magnetic resonance image of the patient's head confirmed multiple brain abscesses and lateral right ventricle enlargement. In this case report, we describe a potential refractory multidrug-resistant infection following a tsunami disaster. Copyright © 2013 The Japanese Respiratory Society. Published by Elsevier B.V. All rights reserved.