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1

Landslide-generated tsunamis in a perialpine lake: Historical events and numerical models  

Science.gov (United States)

Many of the perialpine lakes in Central Europe - the large, glacier-carved basins formed during the Pleistocene glaciations of the Alps - have proven to be environments prone to subaquatic landsliding. Among these, Lake Lucerne (Switzerland) has a particularly well-established record of subaquatic landslides and related tsunamis. Its sedimentary archive documents numerous landslides over the entire Holocene, which have either been triggered by earthquakes, or which occurred apparently spontaneously, possibly due to rapid sediment accumulation on delta slopes. Due to their controlled boundary conditions and the possibility to be investigated on a complete basinal scale, such lacustrine tsunamis may be used as textbook analogons for their marine counterparts. Two events in the 17th century illustrate these processes and their consequences: In AD 1601, an earthquake (Mw ~ 5.9) led to widespread failure of the sediment drape covering the lateral slopes in several basins. The resulting landslides generated tsunami waves that reached a runup of several metres, as reported in historical accounts. The waves caused widespread damage as well as loss of lives in communities along the shores. In AD 1687, the apparently spontaneous collapse of a river delta in the lake led to similar waves that damaged nearby villages. Based on detailed information on topography, bathymetry and the geometry of the landslide deposits, numerical simulations combining two-dimensional, depth-averaged models for landslide propagation, as well as for tsunami generation, propagation and inundation, are able to reproduce most of the reported tsunami effects for these events. Calculated maximum runup of the waves is 6 to >10 m in the directly affected lake basins, but significantly less in neighbouring basins. Flat alluvial plains adjacent to the most heavily affected areas are inundated over distances of several hundred metres. Taken as scenarios for possible future events, these past events suggest that tsunami hazard in these lake should not be neglected, although they are infrequent and the effects are naturally limited to the immediate surroundings of the affected basins. The shores of Lake Lucerne, as well as of many other perialpine lakes, are nowadays densely inhabited and host considerable infrastructure, so that events similar to those reported may have serious consequences. Identification and mapping of possible subaquatic landslide source areas, the inclusion of geotechnical data on potentially mobile sediments, as well as numerical modelling of tsunamis are thus important components of a proper hazard assessment for these lakes.

Hilbe, Michael; Anselmetti, Flavio S.

2014-05-01

2

Integrated Historical Tsunami Event and Deposit Database  

Science.gov (United States)

The National Geophysical Data Center (NGDC) provides integrated access to historical tsunami event, deposit, and proxy data. The NGDC tsunami archive initially listed tsunami sources and locations with observed tsunami effects. Tsunami frequency and intensity are important for understanding tsunami hazards. Unfortunately, tsunami recurrence intervals often exceed the historic record. As a result, NGDC expanded the archive to include the Global Tsunami Deposits Database (GTD_DB). Tsunami deposits are the physical evidence left behind when a tsunami impacts a shoreline or affects submarine sediments. Proxies include co-seismic subsidence, turbidite deposits, changes in biota following an influx of marine water in a freshwater environment, etc. By adding past tsunami data inferred from the geologic record, the GTD_DB extends the record of tsunamis backward in time. Although the best methods for identifying tsunami deposits and proxies in the geologic record remain under discussion, developing an overall picture of where tsunamis have affected coasts, calculating recurrence intervals, and approximating runup height and inundation distance provides a better estimate of a region’s true tsunami hazard. Tsunami deposit and proxy descriptions in the GTD_DB were compiled from published data found in journal articles, conference proceedings, theses, books, conference abstracts, posters, web sites, etc. The database now includes over 1,200 descriptions compiled from over 1,100 citations. Each record in the GTD_DB is linked to its bibliographic citation where more information on the deposit can be found. The GTD_DB includes data for over 50 variables such as: event description (e.g., 2010 Chile Tsunami), geologic time period, year, deposit location name, latitude, longitude, country, associated body of water, setting during the event (e.g., beach, lake, river, deep sea), upper and lower contacts, underlying and overlying material, etc. If known, the tsunami source mechanism (e.g., earthquake, landslide, volcanic eruption, asteroid impact) is also specified. Observations (grain size, sedimentary structure, bed thickness, number of layers, etc.) are stored along with the conclusions drawn from the evidence by the author (wave height, flow depth, flow velocity, number of waves, etc.). Geologic time periods in the GTD_DB range from Precambrian to Quaternary, but the majority (70%) are from the Quaternary period. This period includes events such as: the 2004 Indian Ocean tsunami, the Cascadia subduction zone earthquakes and tsunamis, the 1755 Lisbon tsunami, the A.D. 79 Vesuvius tsunami, the 3500 BP Santorini caldera collapse and tsunami, and the 7000 BP Storegga landslide-generated tsunami. Prior to the Quaternary period, the majority of the paleotsunamis are due to impact events such as: the Tertiary Chesapeake Bay Bolide, Cretaceous-Tertiary (K/T) Boundary, Cretaceous Manson, and Devonian Alamo. The tsunami deposits are integrated with the historical tsunami event database where applicable. For example, users can search for articles describing deposits related to the 1755 Lisbon tsunami and view those records, as well as link to the related historic event record. The data and information may be viewed using tools designed to extract and display data (selection forms, Web Map Services, and Web Feature Services).

Dunbar, P. K.; McCullough, H. L.

2010-12-01

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Tsunami Warning Criteria for Cascadia events based on Tsunami models  

Science.gov (United States)

Initial tsunami warning, advisory, and watch zones for potential Cascadia earthquakes have been revised based on maximum expected threat for tsunamis generated by earthquakes in this region. Presently, alert zones are initially based on travel time for earthquakes greater than magnitude 7.8 with all areas less than three hours away from the source being put into a tsunami warning. The impact of this change is to reduce the length of coastline which is immediately put it into a warning status. Tsunami Warning Centers often delineate initial tsunami alert zones based on pre-set criteria dependent on earthquake magnitude, location, depth, and tsunami travel time. In many cases, this approach can lead to over-warning. Over the last several years, the West Coast/Alaska Tsunami Warning Center (WCATWC) has attempted to refine the amount of coastline immediately placed in a warning status based on maximum expected threat instead of travel time. Tsunami forecast models used to predict impacts during events (for example, Alaska Tsunami Forecast Model (ATFM), Short-term Inundation Forecasting for Tsunamis (SIFT), and Rapid Inundation Forecasting of Tsunamis (RIFT)) can also be used a-priori to delineate zones at-risk for specified source zones. forecast models have proven reasonably accurate during recent events. For the Cascadia Subduction zone, several rupture scenarios ranging from magnitude 7.9 to 9.2, were computed. Forecasted wave heights at various points are then used to set the initial Warning/Watch/Advisory regions. This procedure is more efficient than a blanket warning - or a refined warning based on travel times - as appropriate threat levels are assigned based on expected impact. For example, after a magnitude 8.7 earthquake in the southern Cascadia Subduction zone, southern and most of central California can be left out of the warning zone and placed in an advisory, as none of this region contains expected impacts in the warning threshold (tsunami amplitude over 1m). Under previous criteria, these zones would have been placed in a warning. Several examples are shown which help refine criteria used by the Tsunami Warning Center during hypothetical Cascadia events.

Huang, P. Y.; Nyland, D. L.; Knight, W.; Gately, K.; Hale, D.; Urban, G.; Waddell, J.; Carrick, J.; Popham, C.; Bahng, B.; Kim, Y.; Burgy, M.; Langley, S.; Preller, C. C.; Whitmore, P.

2013-12-01

4

Tsunami  

Medline Plus

Full Text Available ... What's happening now? Tsunami YouTube videos Feature Archive Basics: The Tsunami Story : Generation, propagation, warning systems, forecasts and reduction of impacts. Basic information about Tsunamis Tsunami Terminology NOAA's Role NOAA's ...

5

Tsunami  

Medline Plus

Full Text Available ... the 50th anniversary of the 1964 Great Alaska Earthquake and Tsunamis Recent Tsunami Events Listen to the Honshu, Japan earthquake on YouTube Honshu, Japan tsunami, March 11, 2011 - ...

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Tsunami: Ocean dynamo generator  

Science.gov (United States)

Secondary magnetic fields are induced by the flow of electrically conducting seawater through the Earth's primary magnetic field (`ocean dynamo effect'), and hence it has long been speculated that tsunami flows should produce measurable magnetic field perturbations, although the signal-to-noise ratio would be small because of the influence of the solar magnetic fields. Here, we report on the detection of deep-seafloor electromagnetic perturbations of 10-micron-order induced by a tsunami, which propagated through a seafloor electromagnetometer array network. The observed data extracted tsunami characteristics, including the direction and velocity of propagation as well as sea-level change, first to verify the induction theory. Presently, offshore observation systems for the early forecasting of tsunami are based on the sea-level measurement by seafloor pressure gauges. In terms of tsunami forecasting accuracy, the integration of vectored electromagnetic measurements into existing scalar observation systems would represent a substantial improvement in the performance of tsunami early-warning systems.

Sugioka, Hiroko; Hamano, Yozo; Baba, Kiyoshi; Kasaya, Takafumi; Tada, Noriko; Suetsugu, Daisuke

2014-01-01

7

Tsunamis  

Science.gov (United States)

... with these terms to help identify a tsunami hazard: Warning A tsunami warning is issued when a tsunami with the potential to generate widespread inundation is imminent or expected. Warnings alert the public ...

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Nonlinear tsunami generation mechanism  

Directory of Open Access Journals (Sweden)

Full Text Available The nonlinear mechanism of long gravitational surface water wave generation by high-frequency bottom oscillations in a water layer of constant depth is investigated analytically. The connection between the surface wave amplitude and the parameters of bottom oscillations and source length is investigated.

M. A. Nosov

2001-01-01

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Detailed analysis of tsunami waveforms generated by the 1946 Aleutian tsunami earthquake  

Digital Repository Infrastructure Vision for European Research (DRIVER)

The 1946 Aleutian earthquake was a typical tsunami earthquake which generated abnormally larger tsunami than expected from its seismic waves. Previously, Johnson and Satake (1997) estimated the fault model of this earthquake using the tsunami waveforms observed at tide gauges. However, they did not model the second pulse of the tsunami at Honolulu although that was much larger than the first pulse. In this paper, we numerically computed the tsunami waveforms using the linear Boussinesq equati...

Tanioka, Y.; Seno, T.

2001-01-01

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VOLCANIC TSUNAMI GENERATING SOURCE MECHANISMS IN THE EASTERN CARIBBEAN REGION  

Directory of Open Access Journals (Sweden)

Full Text Available Earthquakes, volcanic eruptions, volcanic island flank failures and underwater slides have generated numerous destructive tsunamis in the Caribbean region. Convergent, compressional and collisional tectonic activity caused primarily from the eastward movement of the Caribbean Plate in relation to the North American, Atlantic and South American Plates, is responsible for zones of subduction in the region, the formation of island arcs and the evolution of particular volcanic centers on the overlying plate. The inter-plate tectonic interaction and deformation along these marginal boundaries result in moderate seismic and volcanic events that can generate tsunamis by a number of different mechanisms. The active geo-dynamic processes have created the Lesser Antilles, an arc of small islands with volcanoes characterized by both effusive and explosive activity. Eruption mechanisms of these Caribbean volcanoes are complex and often anomalous. Collapses of lava domes often precede major eruptions, which may vary in intensity from Strombolian to Plinian. Locally catastrophic, short-period tsunami-like waves can be generated directly by lateral, direct or channelized volcanic blast episodes, or in combination with collateral air pressure perturbations, nuéss ardentes, pyroclastic flows, lahars, or cascading debris avalanches. Submarine volcanic caldera collapses can also generate locally destructive tsunami waves. Volcanoes in the Eastern Caribbean Region have unstable flanks. Destructive local tsunamis may be generated from aerial and submarine volcanic edifice mass edifice flank failures, which may be triggered by volcanic episodes, lava dome collapses, or simply by gravitational instabilities. The present report evaluates volcanic mechanisms, resulting flank failure processes and their potential for tsunami generation. More specifically, the report evaluates recent volcanic eruption mechanisms of the Soufriere Hills volcano on Montserrat, of Mt. Pelée on Martinique, of Soufriere on St. Vincent and of the Kick’em Jenny underwater volcano near Grenada and provides an overall risk assessment of tsunami generation from volcanic sources in the Caribbean region.

George Pararas-Carayannis

2004-01-01

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Tsunami Impact from a 1755-like event in the Aveiro Region, Portugal  

Science.gov (United States)

In this study, we present 5m-resolution tsunami flooding maps for the Aveiro region, W. Central Portugal. Aveiro is known to have been impacted by the 1st November 1755 earthquake and tsunami. At that time this portion of the coast had almost no constructions nor population but eversince geomorphological changes took place, and there has been a very large population increase living in constructions extremely close to the shore. As such it is important to model and evaluate the potential impact that a similar event to the 1755 earthquake would have in this area at present. Tsunami flooding maps were computed using a digital elevation model produced from the present-day bathymetric and topographic data including bathymetric surveys, LiDAR and photogrammetric data. Tsunami scenarios were generated considering different solutions for the 1755 earthquake seismic source, in faults constrained by multibeam and multichannel seismic data. The modeling of the tsunami propagation was performed with a validated non-linear shallow water model. To compute inundation, we considered four levels of nested grids with resolutions ranging from 320m to 5m. The tsunami-associated flood is discussed in terms of flow depth, run-up height and maximum inundation area. The Ria de Aveiro is characterized by both flattened relief and significant tidal amplitude range, which can contribute to an important variation in flooding due to tsunami-tide interaction. Therefore, the effect of the tide variation on the extent of tsunami inundation is also discussed. Results are compared with the historical descriptions of the consequences in Aveiro. An event similar to the one from 1755 would cause tsunami run-up heights above one meter within the Ria de Aveiro. The Aveiro oceanic coast would also be strongly affected. The results obtained can be used to identify the potential tsunami inundation areas in Aveiro, which is important for the Portuguese tsunami emergency management system. Keywords: Inundation, DEM, Numerical Modeling, Ria de Aveiro, LiDAR

Lemos, Catarina R.; Omira, Rachid; Pinheiro, Luis M.; Baptista, Maria A.; Quaresma, Luis S.; Garrido, Carla

2014-05-01

12

Tsunami  

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Full Text Available ... primary responsibility for providing tsunami warnings to the Nation, and a leadership role in tsunami observations and research. Information! NOAAWatch Tsunami website United States East Coast Tsunami Threat Tracking Marine Debris ...

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Numerical modelling of historical landslide-generated tsunamis in the French Lesser Antilles  

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Full Text Available Two historical landslide-induced tsunamis that reached the coasts of the French Lesser Antilles are studied. First, the Martinique coast was hit by a tsunami down the western flank of Montagne Pelée at the beginning of the big eruption of May 1902. More recently, the northeastern coast of Guadeloupe was affected by a tsunami that had been generated around Montserrat by pyroclastic flows entering the sea, during the July 2003 eruption of the Soufrière Hills volcano. We use a modified version of the GEOWAVE model to compute numerical simulations of both events. Two source hypotheses are considered for each tsunami. The comparison of the simulation results with reported tsunami height data helps to discriminate between the tested source decriptions. In the Martinique case, we obtain a better fit to data when considering three successive lahars entering the sea, as a simplified single source leads to an overstimation of the tsunami wave heights at the coast. In the Montserrat case, the best model uses a unique source which volume corresponds to published data concerning the peak volume flow. These findings emphasize the importance of an accurate description of the relevant volume as well as the timing sequence of the source event in landslide-generated tsunami modelling. They also show that considering far-field effects in addition to near-field effects may significantly improve tsunami modelling.

B. Poisson

2010-06-01

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The TRIDEC Virtual Tsunami Atlas - customized value-added simulation data products for Tsunami Early Warning generated on compute clusters  

Science.gov (United States)

The development of new Tsunami Early Warning Systems (TEWS) requires the modelling of spatio-temporal spreading of tsunami waves both recorded from past events and hypothetical future cases. The model results are maintained in digital repositories for use in TEWS command and control units for situation assessment once a real tsunami occurs. Thus the simulation results must be absolutely trustworthy, in a sense that the quality of these datasets is assured. This is a prerequisite as solid decision making during a crisis event and the dissemination of dependable warning messages to communities under risk will be based on them. This requires data format validity, but even more the integrity and information value of the content, being a derived value-added product derived from raw tsunami model output. Quality checking of simulation result products can be done in multiple ways, yet the visual verification of both temporal and spatial spreading characteristics for each simulation remains important. The eye of the human observer still remains an unmatched tool for the detection of irregularities. This requires the availability of convenient, human-accessible mappings of each simulation. The improvement of tsunami models necessitates the changes in many variables, including simulation end-parameters. Whenever new improved iterations of the general models or underlying spatial data are evaluated, hundreds to thousands of tsunami model results must be generated for each model iteration, each one having distinct initial parameter settings. The use of a Compute Cluster Environment (CCE) of sufficient size allows the automated generation of all tsunami-results within model iterations in little time. This is a significant improvement to linear processing on dedicated desktop machines or servers. This allows for accelerated/improved visual quality checking iterations, which in turn can provide a positive feedback into the overall model improvement iteratively. An approach to set-up and utilize the CCE has been implemented by the project Collaborative, Complex, and Critical Decision Processes in Evolving Crises (TRIDEC) funded under the European Union's FP7. TRIDEC focuses on real-time intelligent information management in Earth management. The addressed challenges include the design and implementation of a robust and scalable service infrastructure supporting the integration and utilisation of existing resources with accelerated generation of large volumes of data. These include sensor systems, geo-information repositories, simulations and data fusion tools. Additionally, TRIDEC adopts enhancements of Service Oriented Architecture (SOA) principles in terms of Event Driven Architecture (EDA) design. As a next step the implemented CCE's services to generate derived and customized simulation products are foreseen to be provided via an EDA service for on-demand processing for specific threat-parameters and to accommodate for model improvements.

Löwe, P.; Hammitzsch, M.; Babeyko, A.; Wächter, J.

2012-04-01

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Impact Ejecta in a Possible Tsunami Layer in the Hudson River: Regional or Local Event?  

Science.gov (United States)

Recent discoveries point to a tsunami event in the New York metropolitan area approximately 2300 BP. Our discovery of impact ejecta deposited by the tsunami in the Hudson River suggests that the tsunami was caused by an impact in the Atlantic Ocean.

Cagen, K. T.; Abbott, D.; Nitsche, F.; West, A.; Bunch, T.; Breger, D.; Slagle, A.; Carbotte, S.

2009-03-01

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Hikurangi margin tsunami earthquake generated by slow seismic rupture over a subducted seamount  

Science.gov (United States)

Tsunami earthquakes generate much larger tsunami than their surface wave magnitude would suggest and are a problem for tsunami warning systems. They are often not accompanied by intense or even strong ground shaking and hence do not provide a natural warning for self-evacuation. The lesser-known 1947 Offshore Poverty Bay and Tolaga Bay earthquakes along the east coast of the North Island, New Zealand share many characteristics with other well-known tsunami earthquakes (including low amplitude shaking, long durations and anomalously large tsunami), however these two New Zealand events are rare in that their source area has been imaged directly by long-offset 2D seismic reflection profiles. In this contribution we propose a source model for the 1947 Offshore Poverty Bay tsunami earthquake, recognising that the hypocentre occurs in a region where seismic reflection and magnetic data support the existence of a shallow (earthquakes with complex, low velocity rupture scenarios that enhance tsunami waves, and their role in seismic hazard should not be under-estimated.

Bell, Rebecca; Holden, Caroline; Power, William; Wang, Xiaoming; Downes, Gaye

2014-07-01

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Tsunami hazard in La Réunion island from numerical modeling of historical events  

Digital Repository Infrastructure Vision for European Research (DRIVER)

Whereas major tsunamis have recently affected the southwest Indian Ocean, tsunami hazard in this basin has never been thoroughly examined. Our study contributes to fill in this lack and focuses on La Réunion island for which tsunami hazard related to great earthquakes is evaluated by modeling the scenarios of major historical events. Then, our numerical modeling allow us to compare the tsunami impact at regional scale according to the seismic sources; we thus identify earth...

Quentel, E.; Loevenbruck, A.; He?bert, H.; Allgeyer, S.

2013-01-01

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Tsunami Event - March 11, 2011 Honshu (northeastern Taiheiyou)  

Science.gov (United States)

This website, from NOAA, hosts a collection of links to images, animations, and videos related to the 2011 tsunami in Japan. The graphics display forecast results, showing qualitative and quantitative information about the tsunami, including tsunami wave interaction with ocean floor bathymetric features, and neighboring coastlines. Tsunami model amplitude information is shown color-coded according the scale bar.

Noaa

19

Tsunamis.  

Science.gov (United States)

'Tsunami' is the Japanese name for the gravity wave system formed in the sea following any large scale, short-duration disturbance of the free surface. American researchers now prefer 'tsunami' to 'tidal wave' because of the erroneous tidal connotation. B...

W. G. Van Dorn

1965-01-01

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Tsunami generation, propagation, and run-up with a high-order Boussinesq model  

DEFF Research Database (Denmark)

In this work we extend a high-order Boussinesq-type (finite difference) model, capable of simulating waves out to wavenumber times depth kh <25, to include a moving sea-bed, for the simulation of earthquake- and landslide-induced tsunamis. The extension is straight forward, requiring only an additional term within the kinematic bottom condition. As first test cases we simulate linear and nonlinear surface waves generated from both positive and negative impulsive bottom movements. The computed results compare well against earlier theoretical, numerical, and experimental values. Additionally, we show that the long-time (fully nonlinear) evolution of waves resulting from an upthrusted bottom can eventually result in true solitary waves, consistent with theoretical predictions. It is stressed, however, that the nonlinearity used far exceeds that typical of geophysical tsunamis in the open ocean. The Boussinesq-type model is then used to simulate numerous tsunami-type events generated from submerged landslides, inboth one and two horizontal dimensions. The results again compare well against previous experiments and/or numerical simulations. The new extension compliments recently developed run-up capabilities within this approach, and as demonstrated, the model can therefore treat tsunami events from their initial generation, through their later propagation, and final run-up phases. The developed model is shown to maintain reasonable computational efficiency, and is therefore attractive for the simulation of such events, especially in cases where dispersion is important.

Fuhrman, David R.; Madsen, Per A.

2009-01-01

 
 
 
 
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Identification of elements at risk for a credible tsunami event for Istanbul  

Digital Repository Infrastructure Vision for European Research (DRIVER)

Physical and social elements at risk are identified for a credible tsunami event for Istanbul. For this purpose, inundation maps resulting from probabilistic tsunami hazard analysis for a 10% probability of exceedance in 50 yr are utilised in combination with the geo-coded inventories of building stock, lifeline systems and demographic data. The built environment on Istanbul's shorelines that is exposed to tsunami inundation comprises residential, commercial, industrial, public (governmental/...

Hancilar, U.

2012-01-01

22

Reconstructing the Paleotsunami Event in the Southern Taiwan from the Tsunami Boulders  

Science.gov (United States)

Three tsunami boulders were found at the Jiupeng coast in the Southeastern Taiwan (Matta et al., 2013), and can be the evidence of a paleotsunami event happened within 5000 years. In this study, we intended to reconstruct this tsunami event and learn the potential large tsunami that might attack the southern Taiwan. The first step is to find the possible tsunami sources by means of tsunami reverse tracking method (TRTM). TRTM is developed based on the linear wave theory and dispersion relationship. By TRTM, we can also rule out the impossible ones. The theory and algorithm of TRTM will be introduced in the full paper. As the probable tsunami sources are located, the second step is to setup the tsunami scenarios, and to eliminate the cases with results contradicted with the geophysics evidences. The simulation results provide the information of velocity field, and the third step is to simulate the transportation of the tsunami boulders by BTT (Boulder Transport by Tsunami) model proposed by Immamura et al. (2008), and compare the results with the location of present tsunami boulders. The result of reverse tracking method shows that only the tsunamis from Ryukyu Manila, and Yap Trenches are able to reach the coast of Jiupeng (Fig. 1). However, different initial waveform plays an important role in boulder transportation (Goto et al., 2009). The BTT analysis shows that to move one of the boulder, B3, requires a tsunami with 6 m bore height and 8 m/s current velocity. To reach this criteria, an earthquake tsunami sourcing from Manila trench is the most-possible candidate, and the momentum magnitude of the earthquake has to reach Mw 8. From the result we can see that, if the event happened in the current time, not only Jiupeng will be attacked, but also the coast of southwestern Taiwan will be attacked by the tsunami with wave height up to 2 m (Fig. 1) at both Kaohsiung and Taitung cities with dense populations. Furthermore, the No. 3 nuclear power plant (NPP3) is also located within the dangerous zone with wave height up to 12 m. On the other hand, for the case of boulder B1 which is larger than boulder B3, it requires a tsunami with 14 m incoming wave height and 12 m/s current velocity which may be induced by a tsunami sourcing from the Yap trench, and the earthquake momentum magnitude has to reach Mw 9.5.

KO, L.; Lee, C.; Tsai, Y.; Wu, T.

2013-12-01

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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  

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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.

George Pararas-Carayannis

2012-01-01

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TSUNAMIS OF THE ARABIAN PENINSULA A GUIDE OF HISTORIC EVENTS  

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Full Text Available The Arabian Peninsula has been affected by tsunamis in the past. The Peninsula is bounded by the Persian Gulf on its northeast side, the Red Sea on its west side, and the Arabian Sea, the Gulf of Aden, and the Indian Ocean to its east and south. Each of these areas is very different geographically, tectonically, and bathymetrically.Only two, localized tsunamis have been recorded in the Red Sea and one, doubtful, tsunami in the Persian Gulf. Almost all of the recorded tsunamis along the Arabian Peninsula have occurred on its eastern and southern edge, some, such as the one formed by the 1945 Makran earthquake, were extremely destructive. The Indian Ocean is the most likely source area for future destructive tsunamis that would impact the Arabian Peninsula.

Benjamin R. Jordan

2008-01-01

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Catalogue of tsunamis generated in Italy and in Côte d'Azur, France: a step towards a unified catalogue of tsunamis in Europe  

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Full Text Available This work presents a catalogue of the tsunamis generated in the seas watering the Italian coasts, including the neighbouring area of Côte d'Azur (France. Events generated far from Italy and affecting the Italian coasts are not taken into account here. The catalogue, that we will also call the Quick-Look Catalog (QLC, is organised in three main sections that are named the Quick-Look Table, the Quick-Look Accounts File and the References File, having the respective abbreviations of QLT, QLAF and RF. The QLT is a synoptic table containing the relevant information available for each event, one table row corresponding to one event. More details are provided in the QLAF, where each event is dedicated a specific subsection: here the description of the tsunami includes all essential aspects that are suitably referenced and is preceded by a concise report concerning the tsunami cause. Lastly, the RF is the list of all the papers and publications quoted in the QLT and QLAF. Notice that efforts have been made to qualify each event by means of contemporaneous sources, although later sources and indirect sources, such as existing catalogues, have not been disregarded. Besides, specific recent studies on the events have been given special mention. In this work some general review of the past catalogues of tsunamis and of recent trends in the subject are expressed. Particularly, great attention is given to analysing the CFB of the Italian tsunamis due to Caputo and his collaborators (Caputo and Faita, 1984; Bedosti and Caputo, 1986, the acronym being formed by the ordered initials of the authors. Motivations clarifying the need for a new catalogue of the Italian tsunamis are illustrated circumstantially. The very different philosophies that are at the basis of the CFB and of the present QLC lead to quite diverse products and results, that are summarised by a table where the events included in the CFB and in the QLC are compared: the net effect of the rigorous scrutiny applied to the sources and of the coherent analysis applied to the data is that only 67 events are included in the QLC, which is about one third of the events that can be counted in the CFB.

A. Maramai

1996-06-01

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ASSESSMENT OF POTENTIAL TSUNAMI GENERATION IN CHINA'S BOHAI SEA FROM DIRECT GEOTECTONIC AND COLLATERAL SOURCE MECHANISMS  

Directory of Open Access Journals (Sweden)

Full Text Available The Bohai Sea borders northeastern China's most populous and highest economic valuecoastal areas where several megacities are located. Critical infrastructure facilities exist or areunder construction, including a nuclear power plant and super port facilities. Large reserves of oilhave been discovered and a number of offshore oil platforms have been built. The extent ofdevelopment along coastal areas requires a better assessment of potential tsunami risks. Althoughtsunamis do not pose as much of a threat as earthquakes in this region, locally destructive tsunamishave been generated in the past and future events could have significant impacts on coastalpopulations and China's economy, particularly because most of the development has taken place inlow-lying regions, including river deltas. The present study examines the geotectonics of the Bohaibasin region, the impact of past historical events, and the potential for local tsunami generationfrom a variety of direct and collateral source mechanisms triggered by intra plate earthquakes.More specifically, the present study examines: amajor active faults bounding the Bohai Basin; bthe resulting crustal deformation patterns of tectonic structures that have resulted in catastrophicearthquakes in recent years; c the basin-wide extension - with local inversion - extending into theBohai Sea that generated tsunamigenic earthquakes in 1888 and 1969; and d deformational futureseismic events with the potential to generate local tsunamis directly or by collateral mechanisms offolding, en-echelon bookshelf failures, or from destabilization/dissociation of structuralaccumulations of gas hydrate deposits within the basin's thick sedimentary stratigraphic layers.

G. Pararas Carayannis

2009-01-01

27

Tsunami Generated by a Two-Phase Submarine Debris Flow  

Science.gov (United States)

The general two-phase debris flow model proposed by Pudasaini (2011) is employed to study subaerial and submarine debris flows, and the tsunami generated by the debris impact at lakes and oceans. The model includes several essential physical aspects, including Mohr-Coulomb plasticity for the solid stress, while the fluid stress is modelled as a solid volume fraction gradient enhanced non-Newtonian viscous stress. The generalized interfacial momentum transfer includes the viscous drag, buoyancy, and the virtual mass. The generalized drag covers both the solid-like and fluid-like contributions, and can be applied to linear to quadratic drags. Strong couplings exist between the solid and the fluid momentum transfer. The advantage of the real two-phase debris flow model over classical single-phase or quasi-two-phase models is that by considering the solid (and/or the fluid) volume fraction appropriately, the initial mass can be divided into several (even mutually disjoint) parts; a dry (landslide or rock slide), a fluid (water or muddy water; e.g., dams, rivers), and a general debris mixture material as needed in real flow simulations. This offers a unique and innovative opportunity within a single framework to simultaneously simulate (a) the sliding debris (or landslide), (b) the water lake or ocean, (c) the debris impact at the lake or ocean, (d) tsunami generation and propagation, (e) mixing and separation between the solid and the fluid phases, and (f) sediment transport and deposition process in the bathymetric surface. The new model is applied to two-phase subaerial and submarine debris flows. Benchmark numerical simulations reveal that the dynamics of the debris impact induced tsunamis are fundamentally different than the tsunami generated by pure rock avalanche and landslides. Special attention is paid to study the basic features of the debris impact to the mountain lakes or oceans. This includes the generation, amplification and propagation of the multiple strong and bore-type tsunami waves and run-ups in the coastal lines, and debris slide and deposition at the bottom floor. Strong debris shock waves are generated that travel upstream. Once the debris supply ceases, the shock front is diffused. The model analysis also includes mixing and separation of phases, including inter-phase mass and momentum exchanges and generation and interactions of solid and fluid waves. The state of the solid volume fraction governs the evolution of the fluid extra stress and thus effectively dominates the entire flow dynamics. So, the actual knowledge of the solid volume fraction is essential for the prediction of the turbidity currents, sediment transport and deposition in the subaerial and submarine environments. Applications of this model include (i) the sediment transport on hill slopes, river streams, hydraulic channels (e.g., hydropower dams and plants); lakes, fjords, coastal lines, and aquatic ecology; and (ii) submarine debris impact and the rupture of fiber optic, submarine cables and pipelines in ocean floor, and damage to offshore drilling platforms. The Phase-Froude numbers (the solid and fluid Froude numbers) are introduced that change drastically as the debris mass hits the fluid dam. The Phase-Froude numbers can be subcritical or super-critical, suggesting that the tsunami may be following or preceding the wave generating submarine slide and thus enhancing or reducing the tsunami waves. It is observed that the submarine debris front speed can be faster than the tsunami wave speed. This information can be useful for the early warning strategy in the coastal regions. These findings substantially increase the dynamical understanding of complex multi-phase systems and flows, allowing proper modeling of landslide and debris induced tsunami, the dynamics of turbidity currents and sediment transport, with associated applications in hazard mitigation, geomorphology and sedimentology.

Pudasaini, S. P.

2012-04-01

28

OCEAN-WIDE TSUNAMIS, MAGNITUDE THRESHOLDS, AND 1946 TYPE EVENTS  

Directory of Open Access Journals (Sweden)

Full Text Available An analysis of magnitudes and runups in Hawaii for more than 200 tsunamigenic earthquakes along the margins of the Pacific reveals that all of the earthquakes with moment magnitudes of 8.6 or greater produced significant Pacific-wide tsunamis. Such findings can be used as a basis for early warnings of significant ocean-wide tsunamis as a supplement to, or in the absence of, more comprehensive data from other sources. Additional analysis of magnitude and runup data suggests that 1946 type earthquakes and tsunamis may be more common than previously believed.

Daniel A. Walker

2005-01-01

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Impact-generated Tsunamis: An Over-rated Hazard  

Science.gov (United States)

A number of authors have suggested that oceanic waves (tsunami) created by the impact of relatively small asteroids into the Earth's oceans might cause widespread devastation to coastal cities. If correct, this suggests that asteroids > 100 m in diameter may pose a serious hazard to humanity and could require a substantial expansion of the current efforts to identify earth-crossing asteroids > 1 km in diameter. The debate on this hazard was recently altered by the release of a document previously inaccessible to the scientific community. In 1968 the US Office of Naval Research commissioned a summary of several decades of research into the hazard proposed by waves generated by nuclear explosions in the ocean. Authored by tsunami expert William Van Dorn, this 173-page report entitled Handbook of Explosion-Generated Water Waves affords new insight into the process of impact wave formation, propagation, and run up onto the shoreline.

Melosh, H. J.

2003-01-01

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Numerical modelling of tsunami generation by deformable submarine slides using mesh adaptivity  

Science.gov (United States)

Tsunamis generated by submarine slides are often under considered in comparison to earthquake generated tsunami, despite several recent examples. Tsunamigenic slides have generated waves that have caused significant damage and loss of life, for example the 1998 Papua New Guinea submarine mass failure resulted in a tsunami that devastated coastal villages and killed over 2,100 people. Numerical simulations of submarine slide generated waves can help us understand the nature of the waves that are generated, and identify the important factors in determining wave characteristics. There have not been many studies of tsunami generation by deformable submarine slides, largely because of the complexities and computational expense involved in modelling these large scale events. At large, real world, scales modelling of tsunami waves by the generation of slides is computationally challenging. Fluidity is an open source finite element code that is ideally suited to tackle this type of problem as it uses unstructured, adaptive meshes, which help to reduce the computational expense without losing accuracy in the results. Adaptive meshes change topology and resolution based on the current simulation state and as such can focus or reduce resolution when and where it is required. The model also allows a number of different numerical approaches to be taken to simulate the same problem within the same numerical framework. In this example we use multi-material approach, with both two materials (slide and water) and three materials (slide, water and air), alongside a density-driven sediment model approach. We will present results of validating Fluidity against benchmarks from experimental and other numerical studies, at different scales, for deformable underwater slides, and consider the utility of mesh adaptivity. We show good agreement to both laboratory results and other numerical models, both with a fixed mesh and a dynamically adaptive mesh, tracking important features of the slide geometry as the simulation progresses. This is the first step in being able to simulate both the wave initiation, propagation, and inundation within the same numerical model at real-world scales for submarine slide generated tsunamis.

Smith, Rebecca; Parkinson, Samuel; Hill, Jon; Collins, Gareth; Piggott, Matthew

2014-05-01

31

Multi-scale modelling of submarine landslide-generated tsunamis  

Science.gov (United States)

Submarine landslides can be far larger than terrestrial landslides and many generate destructive tsunamis. The Storegga Slide, offshore Norway, covers an area larger than Scotland and contains 3,000 km3 of material (enough to cover Scotland to a depth of 80 m). This huge slide occurred at 8.2 ka and extends for 800 km down slope. It produced a tsunami with >20 m run-up around the Norwegian Sea, including the Shetlands, and run-ups were typically 3-4 m along the mainland coast of Scotland. The tsunami propagated as far as East Greenland. Northern Europe faces few, if any, other natural hazards that could cause damage on the scale of a repeat Storegga Slide tsunami. Modelling such vast natural disasters is not straightforward. In order to achieve accurate run-up, high resolution is required near the coastlines, but entire oceans must be modelled to account for the vast distances travelled by the wave. Here, we use the open-source, three-dimensional CFD model, Fluidity, to simulate the Storegga landslide-generated tsunami. Fluidity's unstructured meshing allows resolution to vary by orders of magnitude within a single numerical simulation. We present results from multi-scale simulations that capture fine-scale coastal details and at the same time cover a domain spanning the Arctic ocean to capture run-ups on the East Greenland coast. We also compare the effects of modern vs palaeo-bathymetry, which has been neglected in previous numerical modelling studies. Future work will include assessing other potential landslide sites and how landslide dynamics affect the resulting tsunami wave to be used in hazard assessment for Northern Europe. Close-up of the computational mesh around the UK coast, western Norway and as far east as Iceland. The shift in resolution from 750m at the coast to over 20km in open water is clearly visible. Note the high resolution area to the top left which is the Storegga Landslide region.

Hill, J.; Piggott, M. D.; Collins, G. S.; Smith, R. C.; Allison, P. A.

2013-12-01

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An approximate method of short-term tsunami forecast and the hindcasting of some recent events  

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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.

Yu. P. Korolev

2011-11-01

33

QCD event generators  

CERN Document Server

This report is a survey on QCD Event Generator issues of relevance for LEP 2. It contains four main sections: a summary of experience from LEP 1, extrapolations to LEP 2 energies, Monte Carlo descriptions and standardization issues.

Knowles, I G; Blondel, A; Böhrer, A; Buchanan, C D; Charlton, D G; Chu, S L; Chun, S; Dissertori, G; Duchesneau, D; Gary, J W; Gibbs, M; Grefrath, A; Gustafson, G; Häkkinen, J; Hamacher, K; Kato, K; Lönnblad, L; Metzger, W J; Møller, R; Munehisa, T; Odorico, R; Pei, Y; Rudolph, G; Sarkar, S; Seymour, Michael H; Thompson, J C; Todorova, S; Webber, Bryan R

1996-01-01

34

QCD Event Generators  

Digital Repository Infrastructure Vision for European Research (DRIVER)

This report is a survey on QCD Event Generator issues of relevance for LEP 2. It contains four main sections: a summary of experience from LEP 1, extrapolations to LEP 2 energies, Monte Carlo descriptions and standardization issues.

Knowles, I. G.; Sjostrand, T.; Blondel, A.; Boehrer, A.; Buchanan, C. D.; Charlton, D. G.; Chu, S. -l; Chun, S.; Dissertori, G.; Duchesneau, D.; Gary, J. W.; Gibbs, M.; Grefrath, A.; Gustafson, G.; Hakkinen, J.

1996-01-01

35

Identification of elements at risk for a credible tsunami event for Istanbul  

Directory of Open Access Journals (Sweden)

Full Text Available Physical and social elements at risk are identified for a credible tsunami event for Istanbul. For this purpose, inundation maps resulting from probabilistic tsunami hazard analysis for a 10% probability of exceedance in 50 yr are utilised in combination with the geo-coded inventories of building stock, lifeline systems and demographic data. The built environment on Istanbul's shorelines that is exposed to tsunami inundation comprises residential, commercial, industrial, public (governmental/municipal, schools, hospitals, sports and religious, infrastructure (car parks, garages, fuel stations, electricity transformer buildings and military buildings, as well as piers and ports, gas tanks and stations and other urban elements (e.g., recreational facilities. Along the Marmara Sea shore, Tuzla shipyards and important port and petrochemical facilities at Ambarl? are expected to be exposed to tsunami hazard. Significant lifeline systems of the city of Istanbul such as natural gas, electricity, telecommunication and sanitary and waste-water transmission, are also under the threat of tsunamis. In terms of social risk, it is estimated that there are about 32 000 inhabitants exposed to tsunami hazard.

U. Hancilar

2012-01-01

36

Identification of elements at risk for a credible tsunami event for Istanbul  

Science.gov (United States)

Physical and social elements at risk are identified for a credible tsunami event for Istanbul. For this purpose, inundation maps resulting from probabilistic tsunami hazard analysis for a 10% probability of exceedance in 50 yr are utilised in combination with the geo-coded inventories of building stock, lifeline systems and demographic data. The built environment on Istanbul's shorelines that is exposed to tsunami inundation comprises residential, commercial, industrial, public (governmental/municipal, schools, hospitals, sports and religious), infrastructure (car parks, garages, fuel stations, electricity transformer buildings) and military buildings, as well as piers and ports, gas tanks and stations and other urban elements (e.g., recreational facilities). Along the Marmara Sea shore, Tuzla shipyards and important port and petrochemical facilities at Ambarl? are expected to be exposed to tsunami hazard. Significant lifeline systems of the city of Istanbul such as natural gas, electricity, telecommunication and sanitary and waste-water transmission, are also under the threat of tsunamis. In terms of social risk, it is estimated that there are about 32 000 inhabitants exposed to tsunami hazard.

Hancilar, U.

2012-01-01

37

Tsunami Awareness  

Medline Plus

Full Text Available ... the sea surface. Tsunamis can be generated by landslides, volcanic eruptions, or even meteorite impacts in the ... The US Tsunami Warning Centers and NOAA All Hazards Radio. If you find yourself in a location ...

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Numerical modelling of tsunami generated by the 1650 eruption of Kolumbo, South Aegean Sea, Greece  

Science.gov (United States)

Historical 1650 tsunami generated by explosion of Kolumbo volcano was investigated. Using nonlinear shallow water equations implemented in COMCOT tsunami modelling package we simulate for the tsunami generation and propagation, and compute the inundation distances inland along the nearby Santorini island. Two tsunamigenic mechanisms are tested. First, we assume a scenario of phreatomagmatic explosion. Eruption is investigated using a model for shallow underwater explosions. A systematic study is performed for explosion energy range between 1014 and 1017~J. Second, we employed a caldera collapse scenario with duration up to 2~h. The first waves hit the coast of Santorini, the most populated island in the area and also the closest one to Kolumbo ( ˜~7~km), in about 3~min. Calculated inundation distances with predicted nearshore waves amplitudes provide insights into possible tsunami impact and help to assess the tsunami hazard for this region.

Ulvrova, M.; Paris, R.; Kelfoun, K.; Nomikou, P.

2013-12-01

39

Catalogue of reported tsunami events in the Adriatic Sea (from 58 B.C. to 1979 A.D.)  

International Nuclear Information System (INIS)

This catalogue furnishes a collection of the reported tsunamis within the Adriatic, i.e. Italian coasts from the Strait of Otranto to the gulf of Trieste, the coasts of Slovenia, Croatia, Serbia, Montenegro and Albania. The events are obtained by the cross-comparison between many existing catalogues, in order to extract all the available reported ones. For each tsunamigenic event, when available in a catalogue, we report: origin time, location, macroseismic intensity, magnitude and the areas (within Adriatic basin) where tsunamis have been reported. In the last column of the table, all the catalogues in which some information of the event (earthquake and tsunami) has been found, are listed; bold letters indicate the basic catalogue for that event (i.e. the catalogue where the origin time has been taken from). Since in the present catalogue more attention is paid to the tsunamis than to the seismic events, the bold reference indicates always the tsunami-catalogue, and not the seismic ones, when contemporarily available. For some events there are no records of a related tsunami (they are labelled as N.A.T.R.= not available tsunami report) but they are included since their location and magnitude suggest a tsunamigenic potential. (author)

2005-01-01

40

New evidence for the Storegga tsunami event in lake basins systems: western Norway  

Science.gov (United States)

Between 8180 and 8070 years ago, one of the largest known submarine slides occurred off the coast of mid-Norway. This event displaced about 3500 km3 of sediment, affected an area of 95,000 km2 and triggered a large tsunami that inundated coastal areas around the North Atlantic and the North Sea. In this contribution, we present first geological evidence from a high resolution geophysical survey and shallow sediment coring for the presence of a large tsunamite related to the Storegga event, in shallow lacustrine basins of Western Norway. A unique Rapidly Deposited Layer (RDL) discovered in the sedimentary infill of the lakes Nerfloen and Oppstrynsvatnet (29 m a.s.l.) is interpreted as a deposit from this tsunami. Two radiocarbon dates from within the deposit itself yield a combined age estimate of 8180-8030 cal a BP (2?) for the RDL, which is in agreement with robust age-depth modelling of the overlying sediments and strongly supporting the correlation with the Storegga event. In the outer lake basins, where both high-resolution seismic profiles and sediment cores are available, the up to 3.5 m thick RDL covers an area of ~1.1 km2 and features an estimated sediment volume of ~1.2x106 m3. More tentatively we suggest that a ~5x106 m3 semi-transparent seismic unit in the main Oppstrynsvatnet basin could also be connected to the tsunami. Tsunami deposits of this magnitude have not been documented previously in Norwegian lakes, suggesting that the physiographic setting of the study area may have significantly amplified the tsunami wave.

Waldmann, N.; Vasskog, K.; Nesje, A.; Chapron, E.; Ariztegui, D.; Bondevik, S.

2012-12-01

 
 
 
 
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The Tohoku Tsunami of 11 March 2011: The Key Event to Understanding Tsunami Sedimentation on the Coasts of Closed Bays of the Lesser Kuril Islands  

Science.gov (United States)

The Tohoku tsunami of 11 March 2011 manifested in the region of the South Kuril Islands, although, as a rule, the run-up heights in this region did not exceed 3 m. In closed bays that were covered with ice before the tsunami, the eroding capacity of tsunami waves was aggravated by the ice fragments they carried. Here, mud sheets formed, reaching up to 106 m inland. The 2012 studies have shown well-preserved tsunami deposits, evident 1.5 years after the event. A comparative analysis of tsunami deposits from the periphery and from the near-field area close to the tsunami source was performed; this was important for understanding the deposition mechanism during the event, as it had different strengths on different shores. The difference in run-up heights determined the considerable differences in erosion, sedimentation, distribution of tsunami deposits, the formation of sedimentary structures, grain-size composition, and diatom and foraminifera assemblages. The sources of the material also varied significantly from each other: the material came from offshore in closed bays located in the tsunami source periphery, while in the near-field region close to the epicenter, the most active erosion occurred in the inundation area. In the latter area, the main sources of sand were beaches and dunes, while soil erosion was the source of mud. Studies of the Tohoku tsunami on the coasts of the Lesser Kuril Islands demonstrated that mud layers in the sections of coastal lowlands in closed bays could contain preserved detailed geological records of paleotsunamis, even those with a small-height run-up. In the sections of coastal peatlands of closed bays on Shikotan Island, up to 7-9 layers of mud and silty sands were found, these can easily be traced for more than 500 m inland. The grain-size composition of the mud is similar to the deposits of the 2011 Tohoku tsunami. The marine origin of these deposits is confirmed by the diatom analysis data.

Razjigaeva, N. G.; Ganzey, L. A.; Grebennikova, T. A.; Ivanova, E. D.; Kharlamov, A. A.; Kaistrenko, V. M.; Arslanov, Kh. A.; Chernov, S. B.

2014-02-01

42

Tsunami Asymptotics  

Science.gov (United States)

Optical analogies, and some singularity theory, give new information about tsunamis. For most of their propagation, tsunamis are linear dispersive waves whose speed is limited by the depth of the ocean and which can be regarded as diffraction-decorated caustics in spacetime. For constant depth, uniform asymptotics gives a very accurate compact description of the tsunami profile generated by an arbitrary initial disturbance. Variations in depth act as lenses and can focus tsunamis onto cusped caustics, and this ``singularity on a singularity'' constitutes an unusual diffraction problem, whose solution indicates that focusing can amplify the tsunami energy by an order of magnitude.

Berry, Michael

2009-03-01

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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)

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 well as along the western end of the subduction zone. In fact, recent seismic activity indicates that a large earthquake is possible in the region west of the 1945 event. Such an earthquake can be expected to generate a destructive tsunami.Additionally, the on-going subduction of the two micro-plates has dragged tertiary marine sediments into an accretionary prism - thus forming the Makran coastal region, Thick sediments, that have accumulated along the deltaic coastlines from the erosion of the Himalayas, particularly along the eastern Sindh region near the Indus River delta, have the potential to fail and cause large underwater tsunamigenic slides. Even smaller magnitude earthquakes could trigger such underwater landslides. Finally, an earthquake similar to that of 1945 in the Makran zone of subduction, has the potential of generating a bookshelf type of failure within the compacted sediments – as that associated with the “silent” and slow 1992 Nicaragua earthquake – thus contributing to a more destructive tsunami. In conclusion, the Makran subduction zone has a relatively high potential for large tsunamigenic earthquakes.

George Pararas-Carayannis

2006-01-01

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Anatomy of Historical Tsunamis: Lessons Learned for Tsunami Warning  

Science.gov (United States)

Tsunamis are high-impact disasters that can cause death and destruction locally within a few minutes of their occurrence and across oceans hours, even up to a day, afterward. Efforts to establish tsunami warning systems to protect life and property began in the Pacific after the 1946 Aleutian Islands tsunami caused casualties in Hawaii. Seismic and sea level data were used by a central control center to evaluate tsunamigenic potential and then issue alerts and warnings. The ensuing events of 1952, 1957, and 1960 tested the new system, which continued to expand and evolve from a United States system to an international system in 1965. The Tsunami Warning System in the Pacific (ITSU) steadily improved through the decades as more stations became available in real and near-real time through better communications technology and greater bandwidth. New analysis techniques, coupled with more data of higher quality, resulted in better detection, greater solution accuracy, and more reliable warnings, but limitations still exist in constraining the source and in accurately predicting propagation of the wave from source to shore. Tsunami event data collected over the last two decades through international tsunami science surveys have led to more realistic models for source generation and inundation, and within the warning centers, real-time tsunami wave forecasting will become a reality in the near future. The tsunami warning system is an international cooperative effort amongst countries supported by global and national monitoring networks and dedicated tsunami warning centers; the research community has contributed to the system by advancing and improving its analysis tools. Lessons learned from the earliest tsunamis provided the backbone for the present system, but despite 45 years of experience, the 2004 Indian Ocean tsunami reminded us that tsunamis strike and kill everywhere, not just in the Pacific. Today, a global intergovernmental tsunami warning system is coordinated under the United Nations. This paper reviews historical tsunamis, their warning activities, and their sea level records to highlight lessons learned with the focus on how these insights have helped to drive further development of tsunami warning systems and their tsunami warning centers. While the international systems do well for teletsunamis, faster detection, more accurate evaluations, and widespread timely alerts are still the goals, and challenges still remain to achieving early warning against the more frequent and destructive local tsunamis.

Igarashi, Y.; Kong, L.; Yamamoto, M.; McCreery, C. S.

2011-11-01

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A BRIEF HISTORY OF TSUNAMIS IN THE CARIBBEAN SEA  

Digital Repository Infrastructure Vision for European Research (DRIVER)

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 tsunami...

2002-01-01

46

Model-based tsunami warnings derived from observed impacts  

Digital Repository Infrastructure Vision for European Research (DRIVER)

The Joint Australian Tsunami Warning Centre uses the T2 tsunami scenario database to provide forecast guidance for potential tsunami threats to the coastlines of mainland Australia and its external territories. This study describes a method for generating coastal tsunami warnings from model data obtained from the T2 scenario database. Consideration of observed coastal impacts for nine past events leads to retrospective or "ideal" warning schemes being designed. The 95th perc...

Allen, S. C. R.; Greenslade, D. J. M.

2010-01-01

47

Event generators for address event representation transmitters  

Science.gov (United States)

Address Event Representation (AER) is an emergent neuromorphic interchip communication protocol that allows for real-time virtual massive connectivity between huge number neurons located on different chips. By exploiting high speed digital communication circuits (with nano-seconds timings), synaptic neural connections can be time multiplexed, while neural activity signals (with mili-seconds timings) are sampled at low frequencies. Also, neurons generate 'events' according to their activity levels. More active neurons generate more events per unit time, and access the interchip communication channel more frequently, while neurons with low activity consume less communication bandwidth. In a typical AER transmitter chip, there is an array of neurons that generate events. They send events to a peripheral circuitry (let's call it "AER Generator") that transforms those events to neurons coordinates (addresses) which are put sequentially on an interchip high speed digital bus. This bus includes a parallel multi-bit address word plus a Rqst (request) and Ack (acknowledge) handshaking signals for asynchronous data exchange. There have been two main approaches published in the literature for implementing such "AER Generator" circuits. They differ on the way of handling event collisions coming from the array of neurons. One approach is based on detecting and discarding collisions, while the other incorporates arbitration for sequencing colliding events . The first approach is supposed to be simpler and faster, while the second is able to handle much higher event traffic. In this article we will concentrate on the second arbiter-based approach. Boahen has been publishing several techniques for implementing and improving the arbiter based approach. Originally, he proposed an arbitration squeme by rows, followed by a column arbitration. In this scheme, while one neuron was selected by the arbiters to transmit his event out of the chip, the rest of neurons in the array were freezed to transmit any further events during this time window. This limited the maximum transmission speed. In order to improve this speed, Boahen proposed an improved 'burst mode' scheme. In this scheme after the row arbitration, a complete row of events is pipelined out of the array and arbitered out of the chip at higher speed. During this single row event arbitration, the array is free to generate new events and communicate to the row arbiter, in a pipelined mode. This scheme significantly improves maximum event transmission speed, specially for high traffic situations were speed is more critical. We have analyzed and studied this approach and have detected some shortcomings in the circuits reported by Boahen, which may render some false situations under some statistical conditions. The present paper proposes some improvements to overcome such situations. The improved "AER Generator" has been implemented in an AER transmitter system

Serrano-Gotarredona, Rafael; Serrano-Gotarredona, Teresa; Linares Barranco, Bernabe

2005-06-01

48

EXPERIMENTAL MODELING OF TSUNAMI GENERATED BY UNDERWATER LANDSLIDES  

Directory of Open Access Journals (Sweden)

Full Text Available Preliminary results from a set of laboratory experiments aimed at producing a high-quality dataset for modeling underwater landslide-induced tsunami are presented. A unique feature of these experiments is the use of a method to measure water surface profiles continuously in both space and time rather than at discrete points. Water levels are obtained using an optical technique based on laser induced fluorescence, which is shown to be comparable in accuracy and resolution to traditional electrical point wave gauges. The ability to capture the spatial variations of the water surface along with the temporal changes has proven to be a powerful tool with which to study the wave generation process.In the experiments, the landslide density and initial submergence are varied and information of wave heights, lengths, propagation speeds, and shore run-up is measured. The experiments highlight the non- linear interaction between slider kinematics and initial submergence, and the wave field.The ability to resolve water levels spatially and temporally allows wave potential energy time histories to be calculated. Conversion efficiencies range from 1.1%-5.9% for landslide potential energy into wave potential energy. Rates for conversion between landslide kinetic energy and wave potential energy range between 2.8% and 13.8%.The wave trough initially generated above the rear end of the landslide propagates in both upstream and downstream directions. The upstream-travelling trough creates the large initial draw-down at the shore. A wave crest generated by the landslide as it decelerates at the bottom of the slope causes the maximum wave run-up height observed at the shore.

Langford P. Sue

2006-01-01

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TWO DECADES OF GLOBAL TSUNAMIS - 1982-2002  

Directory of Open Access Journals (Sweden)

Full Text Available The principal purpose of this catalog is to extend the cataloging of tsunami occurrences and effects begun in 1988 by Soloviev, Go, and Kim (Catalog of Tsunamis in the Pacific 1969 to 1982 to the period extending from 1982 through 2001, and to provide a convenient source of tsunami data and a reference list for tsunamis in this period. While the earlier catalogs by Soloviev were restricted to the Pacific region including Indonesia, this catalog reports on known tsunamis worldwide. The year 1982 was included in this catalog because the data in the Soloviev and Go catalog for that year was incomplete.The Pacific is by far the most active zone for tsunami generation but tsunamis have been generated in many other bodies of water including the Caribbean and Mediterranean Seas, and Indian and Atlantic Oceans and other bodies of water. There were no known tsunamis generated in the Atlantic Ocean in the period from 1982 to 2001 but they have occurred there historically. North Atlantic tsunamis include the tsunami associated with the 1755 Lisbon earthquake that caused up to 60,000 fatalities in Portugal, Spain, and North Africa. This tsunami generated waves of up to seven meters in height into the Caribbean. Since 1498 the Caribbean has had 37 verified tsunamis (local and remote sourced plus an additional 52 events that may have resulted in tsunamis. The death toll from these events is about 9,500 fatalities. In 1929, the Grand Banks tsunami off the coast of Labrador generated waves of up to 15 meters in Newfoundland, Canada, killing 26 people, and the waves were recorded along the New Jersey coast. Smaller Atlantic coast tsunamis have been generated in the Norwegian fjords, Iceland, and off the coast of the New England states of the United States. Major tsunamis have also occurred in the Marmara Sea in Turkey associated with the Izmit earthquake of August 17, 1999.

Patricia A. Lockridge

2003-01-01

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Numerical simulation of tsunami generation by cold volcanic mass flows at Augustine Volcano, Alaska  

Directory of Open Access Journals (Sweden)

Full Text Available Many of the world's active volcanoes are situated on or near coastlines. During eruptions, diverse geophysical mass flows, including pyroclastic flows, debris avalanches, and lahars, can deliver large volumes of unconsolidated debris to the ocean in a short period of time and thereby generate tsunamis. Deposits of both hot and cold volcanic mass flows produced by eruptions of Aleutian arc volcanoes are exposed at many locations along the coastlines of the Bering Sea, North Pacific Ocean, and Cook Inlet, indicating that the flows entered the sea and in some cases may have initiated tsunamis. We evaluate the process of tsunami generation by cold granular subaerial volcanic mass flows using examples from Augustine Volcano in southern Cook Inlet. Augustine Volcano is the most historically active volcano in the Cook Inlet region, and future eruptions, should they lead to debris-avalanche formation and tsunami generation, could be hazardous to some coastal areas. Geological investigations at Augustine Volcano suggest that as many as 12–14 debris avalanches have reached the sea in the last 2000 years, and a debris avalanche emplaced during an A.D. 1883 eruption may have initiated a tsunami that was observed about 80 km east of the volcano at the village of English Bay (Nanwalek on the coast of the southern Kenai Peninsula. Numerical simulation of mass-flow motion, tsunami generation, propagation, and inundation for Augustine Volcano indicate only modest wave generation by volcanic mass flows and localized wave effects. However, for east-directed mass flows entering Cook Inlet, tsunamis are capable of reaching the more populated coastlines of the southwestern Kenai Peninsula, where maximum water amplitudes of several meters are possible.

C. F. Waythomas

2006-01-01

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Evidence of tsunami events in the Paleolimnological record of Lake Pátzcuaro, Michoacán, Mexico  

Scientific Electronic Library Online (English)

Full Text Available SciELO Mexico | Language: English Abstract in spanish El actual lago de Pátzcuaro tiene una elevación de 2035 m sobre el nivel del mar. Históricamente, ha alcanzado una elevación de 2041 m, lo cual aislaba una porción de la isla cerca de la población de Jarácuaro en la parte sureste del lago. Dos trincheras realizadas en la antigua isla revelan secuenc [...] ias estratigráficas tripartitas similares. En una trinchera de 3.1 m de profundidad, la secuencia de la base a la cima está formada por la Unidad A que comprende arcillas y limos ricos en diatomeas plegados y fallados con capas de arena volcánica. Estos depósitos están fechados entre 24 y 10 mil años BP. Unidad B que comprende una mezcla caótica de arenas volcánicas y lapilli, con abundantes restos de peces, bivalvos, gasterópodos y ostrácodos, de 10 cm de espesor con un contacto erosivo sobre la Unidad A. Los ostrácodos incluyen valvas articuladas con una mezcla de especies pelágicas de agua profunda y especies litorales. Los fragmentos de artefactos cerámicos pertenecientes al Período Post-Clásico (900 a 1520 AD) son abundantes. La Unidad C comprende una unidad de 20 cm de espesor de limo arcilloso rico en materia orgánica con restos de gasterópodos, semillas, líticos angulares y fragmentos de piezas cerámicas del Post-Clásico. La Unidad B sugiere una resedimentación catastrófica de los depósitos del piso del lago atribuidos a un tsunami. La Unidad C es consistente con condiciones sublacustres que están históricamente documentadas de 1858 a 1947. Un tsunami en el Lago de Pátzcuaro en 1858 ha sido registrado históricamente. El tsunami pudo haber sido creado por movimientos de falla o colapso del flanco suroeste de la isla de Janitzio. La ola del tsunami pudo haber contribuido al rápido aumento del lago de Pátzcuaro después del evento sísmico de 1858. Abstract in english Modern Lake Pátzcuaro has a surface elevation of 2035 m a.s.l. Historically, it reached an elevation of 2041 m a.s.l., which isolated a portion of the island near the town of Jarácuaro in the southeastern part of the lake. Two trenches in the former island reveal similar tripartite stratigraphic seq [...] uences. In a 3.1 m deep trench, the sequence from bottom to top comprises Unit A constituted by folded and faulted diatom-rich clay and silt with beds of volcanic sand. These deposits are dated between 24 and 10 ky BP; Unit B constituted by a 10 of cm chaotic mixture of volcanic sand and lapilli with abundant remains of fish, bivalves, gastropods and ostracodes that is rests on above an erosional unconformity. The ostracodes include articulated valves with a mixture of deep-water pelagic species and attached littoral species. Highly fractured diatom shows a mixture of planktonic and benthic habitats. Fragments of ceramic artifacts dated to the Post-Classic Period (900 to 1520 AD) are abundant; Unit Cconstituted by a 20 cm thick unit of organic-rich argillaceous silt with remains of gastropods, seeds, angular lithoclasts and fragments of Post-Classic ceramic artifacts. Unit B suggests a catastrophic resedi mentation of lake floor deposits attributed to a tsunami. Unit C is consistent with sublacustrine conditions that are historically documented from 1858 to 1947. A tsunami in Lake Pátzcuaro in 1858 has been historically recorded. The tsunami was created either by fault movement or collapse of the SW flank of the island of Janitzio. The tsunami wave may have contributed to the rapid rise of Lake Pátzcuaro following the 1858 seismic event.

Victor Hugo, Garduño-Monroy; Diana Cinthia, Soria-Caballero; Isabel, Israde-Alcántara; Víctor Manuel, Hernández Madrigal; Alejandro, Rodríguez-Ramírez; Mikhail, Ostroumov; Miguel Ángel, Rodríguez-Pascua; Arturo, Chacon-Torres; Juan Carlos, Mora-Chaparro.

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The Tsunami Geology of the Bay of Bengal Shores and the Predecessors of the 2004 Indian Ocean Event  

Science.gov (United States)

The 2004 Aceh-Andaman earthquake exceeded the known Indian Ocean precedents by its 1,300-km long fault rupture and the height and reach of its tsunami. Literature of the ancient Chola dynasty (AD 9-11 centuries) of south India and the archeological excavations allude to a sea flood that crippled the historic port at Kaveripattinam, a trading hub for Southeast Asia. Here, we combine a variety of data from the rupture zone as well as the distant shores to build a tsunami history of the Bay of Bengal. A compelling set of geological proxies of possible tsunami inundation include boulder beds of Car Nicobar Island in the south and the East Island in the northernmost Andaman, a subsided fossil mangrove forest near Port Blair and a washover sedimentation identified in the Kaveripattinam coast of Tamil Nadu, south India. We have developed an extensive chronology for these geological proxies, and we analyze them in conjunction with the historical information culled from different sources for major sea surges along the Bay of Bengal shores. The age data and the depositional characteristics of these geological proxies suggest four major tsunamis in the last 2000 years in the Bay of Bengal, including the 1881 Car Nicobar tsunami. Among these, the evidence for the event of 800-1200 cal yr BP is fairly well represented on both sides of the Bay of Bengal shores. Thus, we surmise that the 800-1000-year old tsunami mimics the transoceanic reach of the 2004 Indian Ocean and the age constraints also agree with the sea surge during the Chola period. We also obtained clues for a possible medieval tsunami from the islands occurred probably a few hundred years after the Chola tsunami, but its size cannot constrained, nor its source. The convergence of ages and the multiplicity of sites would suggest at least one full size predecessor of the 2004 event 1000-800 years ago.

Rajendran, C.; Rajendran, K.; Seshachalam, S.; Andrade, V.

2010-12-01

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Numerical simulations of tsunamis generated by underwater volcanic explosions at Karymskoye lake (Kamchatka, Russia) and Kolumbo volcano (Aegean Sea, Greece)  

Science.gov (United States)

Increasing human activities along the coasts of the world provoke the necessity to assess tsunami hazard from different sources (earthquakes, landslides, volcanic activity). In this paper, we simulate tsunamis generated by underwater volcanic explosions from (1) a submerged vent in a shallow water lake (Karymskoye Lake, Kamchatka), and (2) from Kolumbo submarine volcano (7 km NE of Santorini, Aegean Sea, Greece). The 1996 tsunami in Karymskoye lake is a well-documented example and thus serves as a case study for validating the calculations. The numerical model reproduces realistically the tsunami run-ups measured onshore. Systematic numerical study of tsunamis generated by explosions of the Kolumbo volcano is then conducted for a wide range of energies. Results show that in case of reawakening, the Kolumbo volcano might represent a significant tsunami hazard for the northern, eastern and southern coasts of Santorini, even for small-power explosions.

Ulvrová, M.; Paris, R.; Kelfoun, K.; Nomikou, P.

2014-02-01

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Numerical simulations of tsunami generated by underwater volcanic explosions at Karymskoye lake (Kamchatka, Russia) and Kolumbo volcano (Aegean Sea, Greece)  

Science.gov (United States)

Increasing human activities along the coasts of the world arise the necessity to assess tsunami hazard from different sources (earthquakes, landslides, volcanic activity). In this paper, we simulate tsunamis generated by underwater volcanic explosions from (1) a submerged vent in a shallow water lake (Karymskoye Lake, Kamchatka), and (2) from Kolumbo submarine volcano (7 km NE of Santorini, Aegean Sea, Greece). The 1996 tsunami in Karymskoye lake is a well-documented example and thus serves as a case-study for validating the calculations. The numerical model reproduces realistically the tsunami runups measured onshore. Systematic numerical study of tsunamis generated by explosions of Kolumbo volcano is then conducted for a wide range of energies. Results show that in case of reawakening, Kolumbo volcano might represent a significant tsunami hazard for the northern, eastern and southern coasts of Santorini, even for small-power explosions.

Ulvrová, M.; Paris, R.; Kelfoun, K.; Nomikou, P.

2013-11-01

55

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

Science.gov (United States)

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 concerning its occidental part, that is, the Algerian, Spanish and French coasts.

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

2011-06-01

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Modeling the fate and transport of saltwater discharged into a well during a tsunami event  

Science.gov (United States)

The 2004 Asian tsunami caused considerable contamination of groundwater resources in Sri Lanka. Open wells are widely used in the coastal areas of Sri Lanka for accessing potable water and sea water inundation through these open wells was potentially a major source of groundwater contamination. Various organizations tried to remediate the contamination in these wells through pumping. However, these efforts were ill-coordinated and in most cases the pumping was done without any technical information or scientific basis. There were no guidelines available for pumping wells after a saltwater event at that time. Therefore, there is a strong need for understanding the saltwater migration processes in order to develop a set of guidelines for well cleanup. Our project, funded by international agencies was jointly conducted by a multi-disciplinary team of international scientists. We conducted field and laboratory experiments by simulating tsunami-type inundation events in wells. The field experiments were conducted at a pristine location, unaffected by the tsunami, on the west coast of Sri Lanka. Field experiments are hard to analyze without a supporting investigation, therefore we performed laboratory experiments. Since all real world scenarios cannot be modeled through physical experiments due to resource (time, money and manpower) constraints, well calibrated numerical models are often used to simulate various different cases. The widely used numerical code, SEAWAT, was used to numerically simulate the laboratory experiments and to develop a well-calibrated numerical model. The numerical model was further used to perform a scenario analysis by varying the hydraulic parameters. In the presentation we will discuss the results of the investigations conducted by the team based in the USA that assisted in the development of physical and numerical experiments. In particular, we will present the effect of varying hydraulic parameters on the fate and transport of saltwater discharged into a well.

Goswami, R. R.; Villholth, K. G.; Clement, P. T.

2007-12-01

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Evidence for a Mega-Tsunami Generated by Giant Flank Collapse of Fogo Volcano, Cape Verde  

Science.gov (United States)

Mega-tsunamis generated by ocean island flank collapses are expected to be some of the most hazardous forces of nature, yet evidence for their near-source effects and inferred high run-ups so far is scarce or hotly debated. A newly discovered deposit on the northern coast of Santiago Island (Cape Verde), however, documents the magnitude and run-up height associated with this kind of event. Additionally to chaotic conglomerates distributed from sea-level up to 100 m elevation standing on slopes as steep as 20°, the deposit comprises a number of scattered megaclasts of submarine lava flows, limestone and tuff. The megaclasts are presently located over a higher substructural slope built on younger subaerial lava flows and at elevations ranging 160-220 m a.s.l. All megaclasts correspond to lithologies that crop out exclusively in nearby cliff faces. The origin of this deposit is consequently attributed to an exceptional wave that plucked blocks from the cliff face, transported them inland and deposited them over the higher slopes of the volcanic edifice. The distribution of the megaclasts, together with the local geomorphology, is in agreement with a tsunami that approached the island edifice from the west and was refracted along its northern flank, flooding a series of northwest-oriented valleys. This suggests that the well-known flank collapse of Fogo volcano, located 55 km west of Santiago, is the most likely source, a hypothesis being tested with surface exposure dating. The inferred run-up exceeded 200 m and is consistent with numerical simulations by Paris et al. 2011, implying that the present Fogo island morphology probably developed by at least one giant flank collapse with devastating near-source effects.

Ramalho, R. S.; Madeira, J.; Helffrich, G. R.; Schaefer, J. M.; Winckler, G.; Quartau, R.; Adena, K.

2013-12-01

58

A Probabilistic Tsunami Hazard Assessment for Indonesia  

Science.gov (United States)

We present the first national probabilistic tsunami hazard assessment (PTHA) for Indonesia. This assessment considers tsunami generated from near-field earthquakes sources around Indonesia as well as regional and far-field sources, to define the tsunami hazard at the coastline. The PTHA methodology is based on the established stochastic event-based approach to probabilistic seismic hazard assessment (PSHA) and has been adapted for tsunami. The earthquake source information is primarily based on the recent Indonesian National Seismic Hazard Map and included a consensus-workshop with Indonesia's leading tsunami and earthquake scientists to finalize the seismic source models and logic trees to include epistemic uncertainty. Results are presented in the form of tsunami hazard maps showing the expected tsunami height at the coast for a given return period, and also as tsunami probability maps, showing the probability of exceeding a tsunami height of 0.5m and 3.0m at the coast. These heights define the thresholds for different tsunami warning levels in the Indonesian Tsunami Early Warning System (Ina-TEWS). The results show that for short return periods (100 years) the highest tsunami hazard is the west coast of Sumatra, the islands of Nias and Mentawai. For longer return periods (>500 years), the tsunami hazard in Eastern Indonesia (north Papua, north Sulawesi) is nearly as high as that along the Sunda Arc. A sensitivity analysis of input parameters is conducted by sampling branches of the logic tree using a monte-carlo approach to constrain the relative importance of each input parameter. The results from this assessment can be used to underpin evidence-based decision making by disaster managers to prioritize tsunami mitigation, such as developing detailed inundation simulations for evacuation planning.

Horspool, N.; Pranantyo, I.; Griffin, J.; Latief, H.; Natawidjaja, D.; Kongko, W.; Cipta, A.; Koetapangwa, B.; Anugrah, S.; Thio, H. K.

2012-12-01

59

Tohoku, Japan Tsunami Sets us West Coast Into Ringing  

Science.gov (United States)

Tsunamis can last a long time compared to the geophysical events that generate them. The Tohoku, Japan tsunami of March 11, 2011 was an extreme event that continued to disturb the Pacific Ocean for many days following its initiation. Historically Japan was considered a source of low tsunami wave energy for the US West Coast. However, damage in California from the last great Japan tsunami was second to that suffered during the 1964 Alaska earthquake. Computer animations of the catastrophic Japan tsunami and other recent significant tsunamis combined with seismological techniques help to identify multiple paths of tsunami waves refracted and reflected by complex bathymetry across the Pacific Ocean basin. Using recent large tsunamigenic earthquakes we demonstrate that the long duration and damage noticed during the last great Japan tsunami in the farfield is a result of several factors. Waveguides acting as tsunami lenses and mirrors, including continental margins, direct the tsunami wave energy to diverse locations around the ocean basin; directionality affected by islands and seamounts, large reflections off of South America, bathymetric features far and near the area of impact and shelf geometry may delay and further amplify the main tsunami energy. This has direct implications on the prediction of tsunami impacts since the US West Coast appears to receive maximum waves much later than first wave arrivals.

Barberopoulou, A.; Legg, M. R.; Gica, E.; Legg, G.

2011-12-01

60

Tsunami Modeling and Inundation Mapping in Southcentral Alaska  

Science.gov (United States)

The Alaska Earthquake Information Center (AEIC) participates in the National Tsunami Hazard Mitigation Program by evaluating and mapping potential tsunami inundation of coastal Alaska. We evaluate potential tsunami hazards for several coastal communities near the epicenter of the 1964 Great Alaska Earthquake and numerically model the extent of their inundation due to tsunamis generated by earthquake and landslide sources. Tsunami scenarios include a repeat of the tsunami triggered by the 1964 Great Alaska Earthquake, as well as hypothetical tsunamis generated by an extended 1964 rupture, a Cascadia megathrust earthquake, earthquakes from the Prince William Sound and Kodiak asperities of the 1964 rupture, and a hypothetical Tohoku-type rupture in the Gulf of Alaska region. Local underwater landslide events in several communities are also considered as credible tsunamigenic scenarios. We perform simulations for each of the source scenarios using AEIC's recently developed and tested numerical model of tsunami wave propagation and runup. Results of the numerical modeling are verified by simulating the tectonic and landslide-generated tsunamis observed during the 1964 earthquake. The tsunami scenarios are intended to provide guidance to local emergency management agencies in tsunami hazard assessment, evacuation planning, and public education for reducing future casualties and damage from tsunamis. During the 1964 earthquake, locally generated waves of unknown origin were identified at several communities, located in the western part of Prince William Sound. The waves appeared shortly after the shaking began and swept away most of the buildings while the shaking continued. We model the tectonic tsunami assuming different tsunami generation processes and claim the importance of including both vertical and horizontal displacement into the 1964 tsunami generation process.

Nicolsky, D.; Suleimani, E.; Koehler, R. D.

2013-12-01

 
 
 
 
61

Event generator for pp interactions  

International Nuclear Information System (INIS)

Phenomenological event generator for pp interactions at energy Elab=70 GeV was created. It is based on the Gaussian form of the matrix element of the interaction. The final states involve two protons and pions. Parameters of the generator are fitted for experimental cross-section data. The energy and momentum conservation laws are strongly satisfied. The event generator provides the smallness of the transverse momentum of the final particles

2006-01-01

62

The influence of landslide shape and continental shelf on landslide generated tsunamis along a plane beach  

Directory of Open Access Journals (Sweden)

Full Text Available This work proposes an advancement in analytical modelling of landslide tsunamis propagating along a plane beach. It is divided into two parts. In the first one, the analytical two-horizontal-dimension model of Sammarco and Renzi (2008 for tsunamis generated by a Gaussian-shaped landslide on a plane beach is revised and extended to realistic landslide shapes. The influence of finiteness and shape of the slide on the propagating waves is investigated and discussed. In the second part, a new model of landslide tsunamis propagating along a semi-plane beach is devised to analyse the role of the continental platform in attenuating the wave amplitude along the shoreline. With these parameters taken into account, the fit with available experimental data is enhanced and the model completed.

E. Renzi

2012-05-01

63

Parton Distributions for Event Generators  

CERN Document Server

In this paper, conventional Global QCD analysis is generalized to produce parton distributions optimized for use with event generators at the LHC. This optimization is accomplished by combining the constraints due to existing hard-scattering experimental data with those from anticipated cross sections for key representative SM processes at LHC (by the best available theory) as joint input to the global analyses. The PDFs obtained in these new type of global analyses using matrix elements calculated in any given order will be best suited to work with event generators of that order, for predictions at the LHC. This is most useful for LO event generators at present. Results obtained from a few candidate PDF sets (labeled as CT09MCS, CT09MC1 and CT09MC2) for LO event generators produced in this way are compared with those from other approaches.

Lai, Hung-Liang; Mrenna, Stephen; Nadolsky, Pavel; Stump, Daniel; Tung, Wu-Ki; Yuan, C -P

2009-01-01

64

Event generator for the LHC  

CERN Document Server

In this contribution the new event generation framework Sherpa will be presented. It aims at the full simulation of events at current and future high-energy experiments, in particular the LHC. Some results related to the production of jets at the Tevatron will be discussed.

Gleisberg, T; Krauss, F; Schälicke, A; Schumann, S; Winter, J

2006-01-01

65

Event generator for the LHC  

International Nuclear Information System (INIS)

In this contribution the new event generation framework SHERPA will be presented. It aims at the full simulation of events at current and future high-energy experiments, in particular the LHC. Some results related to the production of jets at the Tevatron will be discussed

2006-04-01

66

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)

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 Mw 7.8 ruptured an up-dip section of the 2007 rupture, west of the South Pagai of Mentawai Islands. It shook the region only gently but woke deadly tsunami up to 14 meter heights and killed about 500 people. Despite it has been a bit quite in the past three years but the amount of strain left on the Mentawai segment, especially under Siberut, Sipora and North Pagai Islands is about Mw 8.8 still, waiting to be released sometime in the near future. Beside Mentawai, stydies on prehistorical earthquakes and mapping off strain budget and releases along the Aceh-Andaman indicates that a Mw 8 or greater earthquake is still possible to occur in the next decades. Moreover, the status and characteristics of the megathrust section south of the Mentawai, the Sunda Strait to south Java Ocean, is largely unknown so far. Nonetheless, we do know that this southernmost section has been quite for the past several hundreds years, suggesting a possible seismic gap, and it is close to dense population of industrial and urban areas. Learning from experience, we should not just prepare for the expected of well known sources but also the unexpected ones.

Natawidjaja, D.

2013-12-01

67

Modeling propagation and inundation of the 11 March 2011 Tohoku tsunami  

Digital Repository Infrastructure Vision for European Research (DRIVER)

On 11 March 2011 the Tohoku tsunami devastated the east coast of Japan, claiming thousands of casualties and destroying coastal settlements and infrastructure. In this paper tsunami generation, propagation, and inundation are modeled to hindcast the event. Earthquake source models with heterogeneous slips are developed in order to match tsunami observations, including a best fit initial sea surface elevation with water levels up to 8 m. Tsunami simulations were compared to buoys in the Pacifi...

2012-01-01

68

Impact of a Cosmic Body into Earth's Ocean and the Generation of Large Tsunami Waves: Insight from Numerical Modeling  

Science.gov (United States)

The strike of a cosmic body into a marine environment differs in several respects from impact on land. Oceans cover approximately 70% of the Earth's surface, implying not only that oceanic impact is a very likely scenario for future impacts but also that most impacts in Earth's history must have happened in marine environments. Therefore, the study of oceanic impact is imperative in two respects: (1) to quantify the hazard posed by future oceanic impacts, including the potential threat of large impact-generated tsunami-like waves, and (2) to reconstruct Earth's impact record by accounting for the large number of potentially undiscovered crater structures in the ocean crust. Reconstruction of the impact record is of crucial importance both for assessing the frequency of collision events in the past and for better predicting the probability of future impact. We summarize the advances in the study of oceanic impact over the last decades and focus in particular on how numerical models have improved our understanding of cratering in the oceanic environment and the generation of waves by impact. We focus on insight gleaned from numerical modeling studies into the deceleration of the projectile by the water, cratering of the ocean floor, the late stage modification of the crater due to gravitational collapse, and water resurge. Furthermore, we discuss the generation and propagation of large tsunami-like waves as a result of a strike of a cosmic body in marine environments.

Wünnemann, K.; Collins, G. S.; Weiss, R.

2010-12-01

69

The Chiemgau Meteorite Impact And Tsunami Event (Southeast Germany): First Osl Dating  

Science.gov (United States)

A more exact dating of the Chiemgau meteorite impact in Bavaria, southeast Germany, that produced a large strewn field of more than 80 craters sized between a few meters and several hundred meters, may provide the indispensable fundament for evaluating its cultural implications and thus enable an extraordinary case study. A straightforward answer has not yet been provided due to e.g. scarce existence of diagnostic material, lack of specialised micromorphologists, absence of absolute dating data etc. Here we report on a first OSL dating applied to a catastrophic impact layer that features both impact ejecta and tsunami characteristics attributed to proposed falls of projectiles into Lake Chiemsee in the impact event. The OSL dating was conducted on a quartzite cobble and four sediment samples collected from an excavated archaeological stratigraphy at Lake Chiemsee that comprised also the impact layer. In a first approach the analyses were based on the assumption of zero luminescence resetting clock from the induced impact shock for the quartzite cobble, and a solar bleaching of tsunamigenerated sediments. Optically Stimulated Luminescence (OSL) was applied using the Single Aliquot Regeneration (SAR) protocol and relevant reliability criteria. For sediments the beta-TL method was also applied. Reported ages fall around the beginning of 2nd millennium BC. Special attention is given to the peculiar situation of OSL dating of material that may have been exposed to impact shock of strongly varying intensity, to excavation, ejection and ejecta emplacement, the latter overprinted by and mixed with tsunami transport processes resulting in possibly very complex bleaching scenarios largely differing from the original assumptions.

Liritzis, I.; Zacharias, N.; Polymeris, G. S.; Kitis, G.; Ernstson, K.; Sudhaus, D.; Neumair, A.; Mayer, W.; Rappenglück, M. A.; Rappenglück, B.

70

Tsunami: the Great Waves  

Science.gov (United States)

... brochure is to increase awareness and knowledge of tsunamis. Please share what you learn; knowing the right ... at the time the July 30, 1995, Chilean tsunami was generated. A is Antofagasta, Chile. Right: Computer ...

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

Science.gov (United States)

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., 2011; Ide at al., 2011; Yagi and Fukahata, 2011; Suzuki et al., 2011). The comparison of two type of moment rate functions, inferred from finite source imaging of tsunami waveforms and seismic waveforms, suggested that there was the time period common to both seismic wave generation and tsunami generation followed by the time period unique to tsunami generation. At this point, we think that comparison of the absolute values of moment rates is not so meaningful between tsunami waveform inversion and seismic waveform inversion, because of general ambiguity of rigidity values of each subfault in the fault region (assuming the rigidity value of 30 GPa of Yoshida et al (2011)). Considering this, the normalized value of moment rate function was also evaluated and it does not change the general feature of two moment rate functions in terms of duration property. Furthermore, the results suggested that tsunami generation process apparently took more time than seismic wave generation process did. Tsunami can be generated even by "extra" motions resulting from many suggested abnormal mechanisms. These extra motions may be attribute to the relatively larger-scale tsunami generation than expected from the magnitude level from seismic ground motion, and attribute to the longer duration of tsunami generation process.

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

2013-12-01

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A STUDY OF THE EFFECT OF PERMEABILITY OF ROCKS IN TSUNAMI GENERATION AND PROPAGATION BY SEISMIC FAULTING USING LINEARIZED SHALLOW – WATER WAVE THEORY  

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Full Text Available The effect of permeability of rocks inside the ocean on Tsunami generation and Propagation is investigated. We study the nature of Tsunami build up and propagation using realistic curvilinear source models. The models are used to study the effect of permeability on tsunami amplitude amplification as a function on spreading velocity and rise time. Effect of permeability on Tsunami waveforms within the frame of the linearized shallow water wave theory for constant water depth are analyzed analytically using Transform methods. It is observed that in the region of highly permeable rocks the tsunami wave run is fast in comparison to low permeable rocks. The amplitude as a function of the propagated uplift length and width are analyzed. The cases of Tsunami-2011 (Japan, Tsunami- 2006 (Srilanka, and Tsunami-2006 (Madras have been demonstrated in the study.

PARUL SAXENA

2012-01-01

73

Tsunami Awareness  

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Full Text Available ... Links: Tsunami.gov TsunamiReady Information from NWS NOAA Weather Radio Nat ional Tsunami Hazard Mitigation Program NOAA Center for Tsunami Research Credits: NOAA National Weather Service NOAA National Ocean Service NOAA National Tsunami ...

74

A BRIEF HISTORY OF TSUNAMIS IN THE CARIBBEAN SEA  

Directory of Open Access Journals (Sweden)

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.

Patricia A. Lockridge

2002-01-01

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Numerical simulation of tsunami generation by cold volcanic mass flows at Augustine Volcano, Alaska  

Digital Repository Infrastructure Vision for European Research (DRIVER)

Many of the world's active volcanoes are situated on or near coastlines. During eruptions, diverse geophysical mass flows, including pyroclastic flows, debris avalanches, and lahars, can deliver large volumes of unconsolidated debris to the ocean in a short period of time and thereby generate tsunamis. Deposits of both hot and cold volcanic mass flows produced by eruptions of Aleutian arc volcanoes are exposed at many locations along the coastlines of the Bering Sea, North Pacific Ocean, and ...

Waythomas, C. F.; Watts, P.; Walder, J. S.

2006-01-01

76

Lessons Learned from the 2011 Great East Japan Tsunami: Performance of Tsunami Countermeasures, Coastal Buildings, and Tsunami Evacuation in Japan  

Science.gov (United States)

In 2011, Japan was hit by a tsunami that was generated by the greatest earthquake in its history. The first tsunami warning was announced 3 min after the earthquake, as is normal, but failed to estimate the actual tsunami height. Most of the structural countermeasures were not designed for the huge tsunami that was generated by the magnitude M = 9.0 earthquake; as a result, many were destroyed and did not stop the tsunami. These structures included breakwaters, seawalls, water gates, and control forests. In this paper we discuss the performance of these countermeasures, and the mechanisms by which they were damaged; we also discuss damage to residential houses, commercial and public buildings, and evacuation buildings. Some topics regarding tsunami awareness and mitigation are discussed. The failures of structural defenses are a reminder that structural (hard) measures alone were not sufficient to protect people and buildings from a major disaster such as this. These defenses might be able to reduce the impact but should be designed so that they can survive even if the tsunami flows over them. Coastal residents should also understand the function and limit of the hard measures. For this purpose, non-structural (soft) measures, for example experience and awareness, are very important for promoting rapid evacuation in the event of a tsunami. An adequate communication system for tsunami warning messages and more evacuation shelters with evacuation routes in good condition might support a safe evacuation process. The combination of both hard and soft measures is very important for reducing the loss caused by a major tsunami. This tsunami has taught us that natural disasters can occur repeatedly and that their scale is sometimes larger than expected.

Suppasri, Anawat; Shuto, Nobuo; Imamura, Fumihiko; Koshimura, Shunichi; Mas, Erick; Yalciner, Ahmet Cevdet

2013-06-01

77

Lost tsunami  

Science.gov (United States)

Numerical simulations support the occurrence of a catastrophic tsunami impacting all of the eastern Mediterranean in early Holocene. The tsunami was triggered by a debris avalanche from Mt. Etna (Sicily, Italy) which entered the Ionian Sea in the order of minutes. Simulations show that the resulting tsunami waves were able to destabilize soft marine sediments across the Ionian Sea floor. This generated the well-known, sporadically located, ``homogenite'' deposits of the Ionian Sea, and the widespread megaturbidite deposits of the Ionian and Sirte Abyssal Plains. It is possible that, ~8 ka B.P., the Neolithic village of Atlit-Yam (Israel) was abandoned because of impact by the same Etna tsunami. Two other Pleistocenic megaturbidite deposits of the Ionian Sea can be explained by previous sector collapses from the Etna area.

Pareschi, Maria Teresa; Boschi, Enzo; Favalli, Massimiliano

2006-11-01

78

3D numerical investigation on landslide generated tsunamis around a conical island  

Science.gov (United States)

This paper presents numerical computations of tsunamis generated by subaerial and submerged landslides falling along the flank of a conical island. The study is inspired by the tsunamis that on 30th December 2002 attacked the coast of the volcanic island of Stromboli (South Tyrrhenian sea, Italy). In particular this paper analyzes the important feature of the lateral spreading of landside generated tsunamis and the associated flooding hazard. The numerical model used in this study is the full three dimensional commercial code FLOW-3D. The model has already been successfully used (Choi et al., 2007; 2008; Chopakatla et al, 2008) to study the interaction of waves and structures. In the simulations carried out in this work a particular feature of the code has been employed: the GMO (General Moving Object) algorithm. It allows to reproduce the interaction between moving objects, as a landslide, and the water. FLOW-3D has been firstly validated using available 3D experiments reproducing tsunamis generated by landslides at the flank of a conical island. The experiments have been carried out in the LIC laboratory of the Polytechnic of Bari, Italy (Di Risio et al., 2009). Numerical and experimental time series of run-up and sea level recorded at gauges located at the flanks of the island and offshore have been successfully compared. This analysis shows that the model can accurately represent the generation, the propagation and the inundation of landslide generated tsunamis and suggests the use of the numerical model as a tool for preparing inundation maps. At the conference we will present the validation of the model and parametric analyses aimed to investigate how wave properties depend on the landslide kinematic and on further parameters such as the landslide volume and shape, as well as the radius of the island. The expected final results of the research are precomputed inundation maps that depend on the characteristics of the landslide and of the island. Finally we will try to apply the code to a real life case i.e. the landslide tsunamis at the coast of the Stromboli island (Italy). SELECTED REFERENCES Choi, B.H. and D. C. Kim and E. Pelinovsky and S. B. Woo, 2007. Three dimensional simulation of tsunami run-up around conical island. Coastal Engineering 54,374 pp. 618-629. Chopakatla, S.C. and T.C. Lipmann and J.E. Richardson, 2008. Field verification of a computational fluid dynamics model for wave transformation and breaking in the surf zone. Journal of Waterway, Port, Coastal, and Ocean Engineering 134(2), pp. 71-80 Di Risio, M., P. De Girolamo, G. Bellotti, A. Panizzo, F. Aristodemo, M. G.Molfetta, and A. F. Petrillo (2009), Landslidegenerated tsunamis runup at the coast of a conical island: New physical model experiments. J. Geophys. Res., 114, C01009, doi:10.1029/2008JC004858 Flow Science, Inc, 2007. FLOW-3D User's Manual.

Montagna, Francesca; Bellotti, Giorgio

2010-05-01

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Probabilistic Hazard for Seismically-Induced Tsunamis in Complex Tectonic Contexts: Event Tree Approach to Seismic Source Variability and Practical Feasibility of Inundation Maps  

Science.gov (United States)

Probabilistic Tsunami Hazard Analysis (PTHA) rests on computationally demanding numerical simulations of the tsunami generation and propagation up to the inundated coastline. We here focus on tsunamis generated by the co-seismic sea floor displacement, which constitute the vast majority of the observed tsunami events, i.e. on Seismic PTHA (SPTHA). For incorporating the full expected seismic source variability, aiming at a complete SPTHA, a very large number of numerical tsunami scenarios is typically needed, especially for complex tectonic contexts, where SPTHA is not dominated by large subduction earthquakes only. Here, we propose a viable approach for reducing the number of simulations for a given set of input earthquakes representing the modelled aleatory uncertainties of the seismic rupture parameters. Our approach is based on a preliminary analysis of the SPTHA of maximum offshore wave height (HMax) at a given target location, and assuming computationally cheap linear propagation. We start with defining an operational SPTHA framework in which we then introduce a simplified Event Tree approach, combined with a Green's functions approach, for obtaining a first controlled sampling and reduction of the effective source parameter space size. We then apply a two-stage filtering procedure to the 'linear' SPTHA results. The first filter identifies and discards all the sources producing a negligible contribution at the target location, for example the smallest earthquakes or those directing most of tsunami energy elsewhere. The second filter performs a cluster analysis aimed at selecting groups of source parameters producing comparable HMax profiles for each earthquake magnitude at the given test site. We thus select a limited set of sources that is subsequently used for calculating 'nonlinear' probabilistic inundation maps at the target location. We find that the optimal subset of simulations needed for inundation calculations can be obtained basing on just the offshore HMax values, provided that the set of the offshore control points is representative of the inundation zone. The two-stage scenario filtering procedure is semi-automatic and it can be easily repeated for different target locations. We describe and test the performances of our approach on a case study in the Mediterranean, considering potential subduction earthquakes on a section of the Hellenic Arc, and for three target sites on the coast of eastern Sicily and one site on the coast of southern Crete. Comparing the filtered SPTHA results with the full set of inundation maps indicates that our approach allows a reduction factor of 75-80% of the numerical simulations needed for practical applications while preserving the consistency of results. The differences are indeed likely within potential epistemic uncertainties, not considered here, such as those related to tsunami generation and propagation models, bathymetric and topographic models, or other basic and less constrained unknowns related to earthquake activity rates or slip distribution probability.

Lorito, Stefano; Selva, Jacopo; Basili, Roberto; Romano, Fabrizio; Tiberti, Mara Monica; Piatanesi, Alessio

2014-05-01

80

Quakes and tsunamis detected by GOCE (Invited)  

Science.gov (United States)

The aerodynamic accelerations measured by GOCE are used to calculate air density variations and air velocity estimates along GOCE orbit track. The detection of infrasonic waves generated by seismic surface waves and gravity waves generated by tsunamis are presented for earthquakes and tsunamis generated in Tohoku (11/03/2011) and Samoa (29/09/2009) regions. For the seismic/infrasonic waves, a wave propagation modelling is presented and synthetic data are compared to GOCE measurements. The travel time and amplitude discrepancies are discussed in terms of lateral velocity variations in the solid Earth and the atmosphere. For the tsunami/gravity waves, a plane wave analysis is performed and relations between vertical velocity, cross-track velocity and density variations are deduced. By using these relations, an indicator of gravity wave presence is constructed. It allows scanning of the GOCE data to search for gravity wave crossings. Simulations of the gravity wave crossing space/time ranges, using models of tsunami and gravity wave propagation, demonstrate that the observed gravity waves coincide with model-predicted tsunami generated gravity waves for the Tohoku event. This study demonstrates that very low earth orbit spacecraft with high-resolution accelerometers are able to detect atmospheric waves generated by the tectonic activity. Such spacecraft may supply additional data to tsunami alert systems in order to validate some tsunami alerts.

Garcia, R.; Doornbos, E.; Bruinsma, S.; Hebert, H.

2013-12-01

 
 
 
 
81

Adaptive triangular discontinuous Galerkin schemes for tsunami propagation and inundation  

Science.gov (United States)

A tsunami simulation framework is presented, which is based on adaptive triangular meshes and a finite element discontiuous Galerkin discretization. This approach allows for high local resolution and geometric accuracy, while maintaining the opportunity to simulate large spatial domains. The dynamically adaptive mesh is generated by the grid library amatos, which is based on a conforming tree based refinement strategy. While the tsunami propagation in the deep ocean is well represented by the nonlinear shallow water equations, special interest is given to the near-shore characteristics of the flow. For this purpose a new mass-conservative well-balanced inundation scheme is developed. This work is part of the ASCETE (Advanced Simulation of Coupled Earthquake and Tsunami Events) project, which aims to better understand the generation of tsunami events. In this course, a simulation framework is developed which couples physics-based rupture generation with hydrodynamic tsunami propagation and inundation.

Vater, Stefan; Behrens, Jörn

2014-05-01

82

Landslide tsunami hazard in the Indonesian Sunda Arc  

Directory of Open Access Journals (Sweden)

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.

S. Brune

2010-03-01

83

Modeling of Tsunami Generation and Propagation by a Spreading Curvilinear Seismic Faulting in Linearized Shallow-Water Wave Theory  

Directory of Open Access Journals (Sweden)

Full Text Available The processes of tsunami evolution during its generation in search for possible amplification mechanisms resulting from unilateral spreading of the sea floor uplift is investigated. We study the nature of the tsunami build up and propagation during and after realistic curvilinear source models represented by a slowly uplift faulting and a spreading slip-fault model. The models are used to study the tsunami amplitude amplification as a function of the spreading velocity and rise time. Tsunami waveforms within the frame of the linearized shallow water theory for constant water depth are analyzed analytically by transform methods (Laplace in time and Fourier in space for the movable source models. We analyzed the normalized peak amplitude as a function of the propagated uplift length, width and the average depth of the ocean along the propagation path.

Hossam S. Hassan

2010-05-01

84

Developing Tsunami fragility curves using remote sensing and survey data of the 2010 Chilean Tsunami in Dichato  

Digital Repository Infrastructure Vision for European Research (DRIVER)

On 27 February 2010, a megathrust earthquake of Mw = 8.8 generated a destructive tsunami in Chile. It struck not only Chilean coast but propagated all the way to Japan. After the event occurred, the post-tsunami survey team was assembled, funded by the Japan Science and Technology Agency (JST), to survey the area severely affected by the tsunami. The tsunami damaged and destroyed numerous houses, especially in the town of Dichato. In order to estimate...

2012-01-01

85

On the moroccan tsunami catalogue  

Digital Repository Infrastructure Vision for European Research (DRIVER)

A primary tool for regional tsunami hazard assessment is a reliable historical and instrumental catalogue of events. Morocco by its geographical situation, with two marine sides, stretching along the Atlantic coast to the west and along the Mediterranean coast to the north, is the country of Western Africa most exposed to the risk of tsunamis. Previous information on tsunami events affecting Morocco are included in the Iberian and/or the Mediterranean lists of tsunami events...

Kaabouben, F.; Baptista, M. A.; Brahim, A. I.; Toto, A.; El Mouraouah, A.

2009-01-01

86

The Tsunami Triggered by the El Asnam (Algeria) Earthquake of 1980: a New Hypothesis of Generation  

Science.gov (United States)

On the 10th of October 1980, a Mw=7.1 earthquake destroyed the town of El Asnam (actual Ech Cheliff, Northern Algeria) causing several thousands of casualties and leading to considerable economic losses for Algeria. This is the biggest instrumentally recorded earthquake in Africa. A lot of measurement campaigns have been immediately set up in order to constrain the fault rupture mechanisms principally using the numerous aftershocks. Then these studies furnish important information concerning principally the focal mechanisms in this area, the length and width of the rupture zone, the depth and the coseismic slip. But although the epicenter has been located about 45 km from the sea, and 15 km east of El Asnam, in the same area of the 1954 Orléansville earthquake (Mw=6.6), it is known to have triggered a small tsunami which was able to reach the south-eastern Spanish Coast in several locations where it has been recorded on tide gages. Thus six maregrams are available from Alicante to Algeciras Several previous studies present this tsunami as the result of a submarine mass failure as the 1954 event which led to the rupture of submarine phone cables. In this work we propose a rupture scenario based on previous studies results as geodetic measurements of vertical movements, aftershocks localization, focal mechanisms determination and identification of geological features among other things. We show that the seismic initial deformation itself, using Okada’s formulae, is able to disturb the sea surface near the Algerian Coast by several centimeters, even at this distance from the epicenter, and propagate a tsunami wave toward the Spanish Coast. The results are compared with historical records in terms of arrival times, polarity and wave amplitudes and discussed, especially concerning the integration of such inland earthquake in the catalog of the future Western Mediterranean Tsunami Warning System. This study was partially funded by the European project TRANSFER which aimed at constraining tsunamigenic sources and hazard zones in Mediterranean Sea more particularly, and by the French ANR project MAREMOTI under contract ANR-08-RISKNAT-05-01c which aims to assess the tsunami hazard for the French Territories.

Roger, J.; Hebert, H.; Briole, P.

2009-12-01

87

International year of planet earth 7. Oceans, submarine land-slides and consequent tsunamis in Canada  

Science.gov (United States)

Canada has the longest coastline and largest continental margin of any nation in the World. As a result, it is more likely than other nations to experience marine geohazards such as submarine landslides and consequent tsunamis. Coastal landslides represent a specific threat because of their possible proximity to societal infrastructure and high tsunami potential; they occur without warning and with little time lag between failure and tsunami impact. Continental margin landslides are common in the geologic record but rare on human timescales. Some ancient submarine landslides are massive but more recent events indicate that even relatively small slides on continental margins can generate devastating tsunamis. Tsunami impact can occur hundreds of km away from the source event, and with less than 2 hours warning. Identification of high-potential submarine landslide regions, combined with an understanding of landslide and tsunami processes and sophisticated tsunami propagation models, are required to identify areas at high risk of impact.

Mosher, D. C.

2009-01-01

88

Event generation at hadron colliders  

International Nuclear Information System (INIS)

This work deals with the accurate simulation of high energy hadron-hadron-collision experiments, as they are currently performed at Fermilab Tevatron or as they are expected at the Large Hadron Collider at CERN. For a precise description of these experiments an algorithm is investigated, which enables the inclusion of exact multi-jet matrix elements in the simulation. The implementation of this algorithm in the event generator ''SHERPA'' and the extension of its parton shower is the main topic of this work. The results are compared with those of other simulation programs and with experimental data

2005-01-01

89

MODELING THE ASIAN TSUNAMI EVOLUTION AND PROPAGATION WITH A NEW GENERATION MECHANISM AND A NON-LINEAR DISPERSIVE WAVE MODEL  

Directory of Open Access Journals (Sweden)

Full Text Available A common approach in modeling the generation and propagation of tsunami is based on the assumption of a kinematic vertical displacement of ocean water that is analogous to the ocean bottom displacement during a submarine earthquake and the use of a non-dispersive long-wave model to simulate its physical transformation as it radiates outward from the source region. In this study, a new generation mechanism and the use of a highly-dispersive wave model to simulate tsunami inception, propagation and transformation are proposed. The new generation model assumes that transient ground motion during the earthquake can accelerate horizontal currents with opposing directions near the fault line whose successive convergence and divergence generate a series of potentially destructive oceanic waves. The new dynamic model incorporates the effects of earthquake moment magnitude, ocean compressibility through the buoyancy frequency, the effects of focal and water depths, and the orientation of ruptured fault line in the tsunami magnitude and directivity.For tsunami wave simulation, the nonlinear momentum-based wave model includes important wave propagation and transformation mechanisms such as refraction, diffraction, shoaling, partial reflection and transmission, back-scattering, frequency dispersion, and resonant wave-wave interaction. Using this model and a coarse-resolution bathymetry, the new mechanism is tested for the Indian Ocean tsunami of December 26, 2004. A new flooding and drying algorithm that consider waves coming from every direction is also proposed for simulation of inundation of low-lying coastal regions.It is shown in the present study that with the proposed generation model, the observed features of the Asian tsunami such as the initial drying of areas east of the source region and the initial flooding of western coasts are correctly simulated. The formation of a series of tsunami waves with periods and lengths comparable to observations are also well simulated with the new generation model. Furthermore, the shoaling behavior of the tsunami waves during flooding of dry land was also simulated by the new run-up algorithm. Finally, the new generation and propagation models can explain the combined and independent effects of various factors in tsunami generation and transformation taking into consideration the properties of the ocean and the geologic disturbance.

Paul C. Rivera

2006-01-01

90

Tsunami Awareness  

Medline Plus

Full Text Available ... Tsunami.gov TsunamiReady Information from NWS NOAA Weather Radio Nat ional Tsunami Hazard Mitigation Program NOAA Center ... US Tsunami Warning Centers and NOAA All Hazards Radio. If you find yourself in a location of ...

91

a Web-Based and Cloud Capable Tsunami Forecast Tool: Tweb  

Science.gov (United States)

With the move from historically desktop-based technologies towards the cloud, it was inevitable that some tsunami forecast applications would also follow this path. This talk describes Tweb, a web-based tsunami forecast application that is under development at the NOAA Center for Tsunami Research for use by domestic and international partners. While the Tweb tool will centralize forecast technology at a single data center, it will also build on existing distributed tools that allow for localized tsunami inundation product generation. Tweb will be an aggregator for these distributed generated tsunami products and will allow a central access point for tsunami event forecast tools and products. This talk describes the NOAA tsunami forecast methodology on which design of the Tweb application is based, the technologies, system architecture, challenges and implementation details of the application. We also discuss the use of Tweb as a model testbed, the distributed forecast tools and their integration into Tweb.

Burger, E. F.; Kamb, L.; Pells, C.; Nakamura, T.

2013-12-01

92

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

Science.gov (United States)

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.

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

2014-02-01

93

A Model Experiment on the Generation of the Tsunami of March 28, 1964 in Alaska.  

Science.gov (United States)

Analysis of the wave record for this tsunami, obtained from a special tsunami recording station at Wake Island, suggests that the tsunami originated from a line source in the form of a monopolar uplift of half-breadth about 20-30 km. Dispersive waves supe...

W. G. Van Dorn

1969-01-01

94

e+ e- event generator EPOCS  

International Nuclear Information System (INIS)

We present a Monte Carlo program EPOCS (Electron POsitron Collision Simulator), which generates e+e- events in high energy region that will be explored by TRISTAN project. Special emphasis is put on the effect of Z0 and possible top quark resonances. The user can control the simulation by selecting the energy and other parameters. Also he can easily incorpolate a new process and/or particles into the program. The central part of this report is a detailed description on the structure and the usage of the program. We would like to stress that the hadronization is based on a number of assumptions, which are made as clear as possible here. (author)

1985-01-01

95

Replacement Sequence of Events Generator  

Science.gov (United States)

The soeWINDOW program automates the generation of an ITAR (International Traffic in Arms Regulations)-compliant sub-RSOE (Replacement Sequence of Events) by extracting a specified temporal window from an RSOE while maintaining page header information. RSOEs contain a significant amount of information that is not ITAR-compliant, yet that foreign partners need to see for command details to their instrument, as well as the surrounding commands that provide context for validation. soeWINDOW can serve as an example of how command support products can be made ITAR-compliant for future missions. This software is a Perl script intended for use in the mission operations UNIX environment. It is designed for use to support the MRO (Mars Reconnaissance Orbiter) instrument team. The tool also provides automated DOM (Distributed Object Manager) storage into the special ITAR-okay DOM collection, and can be used for creating focused RSOEs for product review by any of the MRO teams.

Fisher, Forest; Gladden, Daniel Wenkert Roy; Khanampompan, Teerpat

2008-01-01

96

Development of an online tool for tsunami inundation simulation and tsunami loss estimation  

Science.gov (United States)

The devastating impacts of the 2004 Indian Ocean tsunami highlighted the need for an effective end-to-end tsunami early warning system in the region that connects the scientific components of warning with preparedness of institutions and communities to respond to an emergency. Essential to preparedness planning is knowledge of tsunami risks. In this study, development of an online tool named “INSPIRE” for tsunami inundation simulation and tsunami loss estimation is presented. The tool is designed to accommodate various accuracy levels of tsunami exposure data which will support the users to undertake preliminary tsunami risk assessment from the existing data with progressive improvement with the use of more detailed and accurate datasets. Sampling survey technique is introduced to improve the local vulnerability data with lower cost and manpower. The performance of the proposed methodology and the INSPIRE tool were tested against the dataset in Kamala and Patong municipalities, Phuket province, Thailand. The estimated building type ratios from the sampling survey show the satisfactory agreement with the actual building data at the test sites. Sub-area classification by land use can improve the accuracy of the building type ratio estimation. For the resulting loss estimation, the exposure data generated from detailed field survey can provide the agreeable results when comparing to the actual building damage recorded for the Indian Ocean tsunami event in 2004. However, lower accuracy exposure data derived from sampling survey and remote sensing can still provide a comparative overview of estimated loss.

Srivihok, P.; Honda, K.; Ruangrassamee, A.; Muangsin, V.; Naparat, P.; Foytong, P.; Promdumrong, N.; Aphimaeteethomrong, P.; Intavee, A.; Layug, J. E.; Kosin, T.

2014-05-01

97

Using Media in the Classroom: Learning and Teaching about the 2011 Japanese Earth-Quake, Tsunami and Nuclear Events from a Socio-Scientific and Science Literacy Perspective  

Science.gov (United States)

This article discusses using students' analysis of media coverage of the March 2011 Japanese earthquake, tsunami and nuclear events to develop their knowledge and understanding of geological concepts and related socio-scientific issues. It draws on news reported at that time, identifies themes in those reports, and suggests how this event can be…

Van Rooy, Wilhelmina; Moore, Leah

2012-01-01

98

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

Directory of Open Access Journals (Sweden)

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.

A. Suppasri

2012-01-01

99

Sediment transport on the inner shelf off Khao Lak (Andaman Sea, Thailand) during the 2004 Indian Ocean tsunami and former storm events: evidence from foraminiferal transfer functions  

Science.gov (United States)

We have investigated the benthic foraminiferal fauna from sediment event layers associated with the 2004 Indian Ocean tsunami and former storms that have been retrieved in short sediment cores from offshore environments of the Andaman Sea, off Khao Lak, western Thailand. Species composition and test preservation of the benthic foraminiferal faunas exhibit pronounced changes across the studied sections and provide information on the depositional history of the tsunami layer, particularly on the source water depth of the displaced foraminiferal tests. In order to obtain accurate bathymetric information on sediment provenance, we have mapped the distribution of modern faunas in non-tsunamigenic surface sediments and created a calibration data set for the development of a transfer function. Our quantitative reconstructions revealed that the resuspension of sediment particles by the tsunami wave was restricted to a maximum water depth of approximately 20 m. Similar values were obtained for former storm events, thus impeding an easy distinction of different high-energy events.

Milker, Y.; Wilken, M.; Schumann, J.; Sakuna, D.; Feldens, P.; Schwarzer, K.; Schmiedl, G.

2013-12-01

100

Elegent -- an elastic event generator  

CERN Document Server

Although elastic scattering of nucleons may look like a simple process, it presents a long-lasting challenge for theory. Due to missing hard energy scale, the perturbative QCD can not be applied. Instead, many phenomenological/theoretical models have emerged. In this paper we present a unified implementation of some of the most prominent models in a C++ library, moreover extended to account for effects of the electromagnetic interaction. The library is complemented with a number of utilities. For instance, programs to sample many distributions of interest in four-momentum transfer squared, t, impact parameter, b, and collision energy sqrt(s). These distributions at ISR, SppS, RHIC, Tevatron and LHC energies are available for download from the project web site. Both in the form of ROOT files and PDF figures providing comparisons among the models. The package includes also a tool for Monte-Carlo generation of elastic scattering events, which can easily be embedded in any other program framework.

Kašpar, Jan

2014-01-01

 
 
 
 
101

Tsunami Hazards in San Francisco Bay  

Science.gov (United States)

A prerequisite to probabilistic hazard assessment is a historic event database and identification of all potential sources. We review published and unpublished material to compile a history of tsunami events, peak tsunami heights and tsunami source regions for San Francisco Bay. Since 1850, 51 credible tsunamis have been recorded or observed within the San Francisco Bay area, all but 6 teletsunamis. Only the tsunamis generated by the 1960 Chile earthquake and the 1964 Alaska earthquake caused damage in San Francisco Bay. Both events are characterized by long duration (12 hours) short period oscillations (about 30 minutes) attributed to near-resonance within the Bay (Wilson and Torum, 1968). Magoon (1966) developed an attenuation relation based on the 1960 and 1964 events and shows an amplitude decay by 50 percent of the Presidio value at Alameda and a 90 percent decrease at the northern and southern ends of the Bay. The 1964 tsunami was the most damaging historic event and caused about 177,000 (US dollars) in damages to boats and floating structures, with 1.13 m amplitude waves recorded at the Presidio. Six credible local tsunami events were observed between 1851 and 1906, four attributed to earthquake sources and two to landslides. The largest (0.6 m near Benicia) was caused by the 1898 Mare Island earthquake and is attributed to slip on the Rogers Creep fault. Garcia and Houston (1975) made return estimates for San Francisco Bay, considering only Alaska sources and estimated 100- and 500-year heights of 2.5 and 4.8 meters respectively at the Presidio. These values need to be reassessed in light of other credible teletsunami sources, particularly the Cascadia subduction zone, and local sources including step-overs on regional strike-slip faults and landslides within the bay. We present the results of numerical modeling runs to test Magoon's attenuation models and to compare local and teletsunami source regions.

Dengler, L.; Borrero, J.; Patton, J.

2004-12-01

102

Building Damage and Business Continuity Management in the Event of Natural Hazards: Case Study of the 2004 Tsunami in Sri Lanka  

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Full Text Available The Sumatra Earthquake and Indian Ocean Tsunami event on the 26 December 2004 has provided a unique and valuable opportunity to evaluate the performance of various structures, facilities and lifeline systems during the tsunami wave attacks. There are especially meaningful observations concerning the structural changes due to the tsunami forces, which open up a wide area of research to develop the mitigation procedure. The business restoration process of business companies in terms of buildings, facilities and lifelines have shown greater research interest. In this study, we investigated the restoration process of business sectors in East and South coastal region in Sri Lanka after the 2004 Indian Ocean Tsunami. A field survey was conducted in East and South coast of Sri Lanka, in order to study the affecting parameters to damage assessment in the restoration process of the business companies. The results of the questionnaire-based field survey are then compared with the statistical analysis results. Finally, the factors affecting the restoration process after the tsunami are identified. As a main conclusion, financial support could be the most important reason for delays in restoration. Moreover, it has been observed that the tsunami inundation level of higher than one meter may have had more effect concerning the damage to the structures and requires additional time for restoration than other areas.

Masami Sugiura

2013-01-01

103

ALGERIA’S VULNERABILITY TO TSUNAMIS FROM NEAR-FIELD SEISMIC SOURCES  

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Full Text Available Evaluation of the effects of tsunami damage relative to earthquake damage may help to identify critical coastal zone structures and exposed populations for near field tsunami risk. In this work, we propose to define the ratio between tsunami intensity and earthquake intensity as a measure of near field tsunami vulnerability for coastal communities. This parameter is estimated for 13 tsunami events reported in North Algeria from the 14th century to present. Although the results show that there are no tsunamis that are unusually large for the size of the earthquake that generated them, coastal communities remain at risk from these periodic hazards.We also use tsunami modelling and published information to estimate maximum inundation in Northern Algeria. Then, we generate a flooding map, which reveals the communities, buildings and infrastructure that are exposed to the tsunami hazard. This map shows that the majority of the people in Algiers and Oran live above 5 meters in elevation, and are hence not exposed to the hazard. Despite this, the coastline remains vulnerable to tsunami as earthquakes can damage poorly constructed buildings and other infrastructure, weakening it prior to the arrival of the tsunami. To increase resilience in the coastal zone, tsunami and earthquake awareness, education and preparedness must become a priority in the context of regional early warning programs.

ALGERIA’S VULNERABILITY TO TSUNAMIS FROM NEAR-FIELD SEISMIC SOURCES

2012-01-01

104

Operational Performance of the Second Generation Deep-Ocean Assessment and Reporting of Tsunamis (DART (trademark) II).  

Science.gov (United States)

In March 2005, the National Oceanic and Atmospheric Administration (NOAA) completed the transition from research to operations of the second generation of the Deep-ocean Assessment and Reporting of Tsunamis (DART(TM) II). DART(TM) II systems are a part of...

K. J. Kern L. Locke R. Bouchard S. McArthur W. Hansen

2007-01-01

105

Improving Tsunami Resilience in Europe - ASTARTE  

Science.gov (United States)

The North East Atlantic, Mediterranean and Adjacent Seas (called NEAM by IOC-UNESCO) is known to be exposed to tsunamis and, like other regions of the world, faces increasing levels of risk due to i) the continuous development of coastal areas with critical infrastructures and accumulated values, and ii) the year-round presence of millions of tourists. In recent years, European researchers have greatly advanced knowledge of tsunami hazards and implementation of operational infrastructures, such as the creation of a regional system of candidate tsunami watch providers (CTWP) and national tsunami warning centers (NTWC). However, significant gaps remain and intensified efforts are needed. The ASTARTE (Assessment STrategy And Risk for Tsunami in Europe) is a three-year long EU-funded project, started in November 2013, that aims to develop a comprehensive strategy to mitigate tsunami impact in the NEAM region. To achieve this goal, an interdisciplinary consortium has been assembled. It includes all NEAM CTWPs and expert institutions across Europe and worldwide. ASTARTE will improve i) the basic knowledge on tsunami generation and recurrence with novel empirical data and new statistical analyses for assessing long-term recurrence and hazards of large events in sensitive areas within NEAM, ii) numerical techniques for tsunami simulation focusing on real-time codes, novel statistical emulation approaches, and experiments on damage analysis, and iii) methods for the assessment of hazard, vulnerability, and risk. ASTARTE will also provide i) guidelines for tsunami Eurocodes, ii) better forecasting and warning tools for CTWPs and NTWCs, and iii) guidelines for decision makers to increase the sustainability and resilience of coastal communities. In summary, ASTARTE will develop basic scientific and technical elements allowing for a significant enhancement of the Tsunami Warning System in the NEAM region in terms of monitoring, early warning,forecast, and resilience, with specific implementation in 9 tsunami test sites. Overall, this will lead to the goal of the European/NEAM Horizon 2020 strategy: to foster tsunami resilient communities. www.astarte-project.eu This work is funded by project ASTARTE - Assessment, STrategy And Risk Reduction for Tsunamis in Europe. Grant 603839, 7th FP (ENV.2013.6.4-3 ENV.2013.6.4-3).

Baptista, Maria Ana; Yalciner, Ahmet; Canals, Miquel; Behrens, Joern; Fuhrman, David; Gonzalez, Mauricio; Harbitz, Carl; Kanoglu, Utku; Karanci, Nurai; Lavigne, Franck; Lorito, Stefano; Meghraoui, Mustafa; Melis, Nikolaos S.; Necmioglu, Ocal; Papadopoulos, Gerassimos A.; Rudloff, Alexander; Schindele, François; Terrinha, Pedro; Tinti, Stefano

2014-05-01

106

THE FRENCH TSUNAMI WARNING CENTER FOR THE MEDITERRANEAN AND NORTHEAST ATLANTIC: CENALT  

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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.

H. Hébert

2013-01-01

107

Boulder Deposits on the Southern Spanish Atlantic Coast: Possible Evidence for the 1755 AD Lisbon Tsunami?  

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Full Text Available Field evidence of visible tsunami impacts in Europe is scarce. This research focused on an analysis of large littoral debris and accompanying geomorphic features and their rela- tionship to a tsunami event at Cabo de Trafalgar, located on the southern Spanish Atlantic coast. Relative dating of weathering features as well as minor bioconstructive forms in the littoral zone suggest the Lisbon tsunami of 1755 AD as the event responsible for the large deposits described. This tsunami had run up heights of more than 19 m and was generated at the Gorringe Bank, located 500 km west off the Cape. Tsunami deposits at Cabo de Tra- falgar are the first boulder deposits identified on the southern Spanish Atlantic coast and are located approximately 250 km southeast of the Algarve coast (Portugal, where other geo- morphic evidence for the Lisbon tsunami has been reported.

Dieter Kelletat

2005-01-01

108

Tsunami Awareness  

Medline Plus

Full Text Available ... to the NOAA Web site This site NOAA home ocean news ocean life sci & tech discoveries about locations contribute subscribe resources faqs Home Ocean News Tsunami Awareness Tsunami Awareness Links: Tsunami. ...

109

Dispersion of tsunamis: does it really matter?  

Directory of Open Access Journals (Sweden)

Full Text Available This article focuses on the effect of dispersion in the field of tsunami modeling. Frequency dispersion in the linear long-wave limit is first briefly discussed from a theoretical point of view. A single parameter, denoted as "dispersion time", for the integrated effect of frequency dispersion is identified. This parameter depends on the wavelength, the water depth during propagation, and the propagation distance or time. Also the role of long-time asymptotes is discussed in this context. The wave generation by the two main tsunami sources, namely earthquakes and landslides, are briefly discussed with formulas for the surface response to the bottom sources. Dispersive effects are then exemplified through a semi-idealized study of a moderate-strength inverse thrust fault. Emphasis is put on the directivity, the role of the "dispersion time", the significance of the Boussinesq model employed (dispersive effect, and the effects of the transfer from bottom sources to initial surface elevation. Finally, the experience from a series of case studies, including earthquake- and landslide-generated tsunamis, is presented. The examples are taken from both historical (e.g. the 2011 Japan tsunami and the 2004 Indian Ocean tsunami and potential tsunamis (e.g. the tsunami after the potential La Palma volcanic flank collapse. Attention is mainly given to the role of dispersion during propagation in the deep ocean and the way the accumulation of this effect relates to the "dispersion time". It turns out that this parameter is useful as a first indication as to when frequency dispersion is important, even though ambiguity with respect to the definition of the wavelength may be a problem for complex cases. Tsunamis from most landslides and moderate earthquakes tend to display dispersive behavior, at least in some directions. On the other hand, for the mega events of the last decade dispersion during deep water propagation is mostly noticeable for transoceanic propagation.

S. Glimsdal

2013-06-01

110

Tsunami generated by a granular collapse down a rough inclined plane  

Science.gov (United States)

In this letter, we experimentally investigate the collapse of initially dry granular media into water and the subsequent impulse waves. We systematically characterize the influence of the slope angle and the granular material on the initial amplitude of the generated leading wave and the evolution of its amplitude during the propagation. The experiments show that whereas the evolution of the leading wave during the propagation is well predicted by a solution of the linearized Korteweg-de Vries equation, the generation of the wave is more complicated to describe. Our results suggest that the internal properties of the granular media and the interplay with the surrounding fluid are important parameters for the generation of waves at low velocity impacts. Moreover, the amplitude of the leading wave reaches a maximum value at large slope angle. The runout distance of the collapse is also shown to be smaller in the presence of water than under totally dry conditions. This study provides a first insight into tsunamis generated by subaerial landslides at low Froude number.

Viroulet, S.; Sauret, A.; Kimmoun, O.

2014-02-01

111

A case study of sanitary survey on community drinking water supplies after a severe (post-Tsunami) flooding event.  

Science.gov (United States)

This report presents a case study of a comprehensive sanitary survey on ca. 160 community drinking water supplies after a severe (post-Tsunami) flooding event in Sri Lanka. Sanitary inspection and microbiological and chemical water quality analyses were performed according to specifically-designed procedures established on the World Health Organization (WHO) guidelines. Significant hazards and critical points were identified in almost all the investigated water supplies. The overall results showed a significant level of microbiological and chemical risk associated with drinking water consumption within the investigated areas. The criteria and methods practised in this study are proposed as a model to assure an effective and reliable monitoring in post-emergencies involving possible deterioration of water quality and to identify health priorities related to water consumption. PMID:20847455

Ferretti, Emanuele; Bonadonna, Lucia; Lucentini, Luca; Della Libera, Simonetta; Semproni, Maurizio; Ottaviani, Massimo

2010-01-01

112

Does MoSE cope with inland tsunamis hazard?  

CERN Document Server

In this work we use morphostructural zonation and pattern recognition techniques to identify a potential seismic source located inland very near Venice, and then we evaluate how a tsunami wave generated from this source can affect the MoSE gates if they are standing up (closed) during the tsunami event. From our simulation we get both peaks and troughs as first arrivals: the behavior of the barriers in these two situations could be a very important design matter.

Panza, Giuliano Francesco; Romanelli, Fabio

2014-01-01

113

New Operational Tsunami Forecast: Accuracy Assessment of Tsunami Amplitude Predictions  

Science.gov (United States)

NOAA has accepted a new tsunami forecast method in operational use to predict tsunami flooding, amplitudes and other tsunami parameters in real-time, while tsunami is still propagating. The method (called Short-term Inundation Forecast for Tsunamis -- SIFT) uses DART real-time data to improve the accuracy of coastal tsunami forecast, when compared with just the seismic data-based assessment. The main goal of the forecast system is to forecast flooding due to tsunami wave at specific coastal locations. Other tsunami parameters are also computed to estimate overall hazard at a given location for a specific tsunami event. Knowing the accuracy of the forecast is extremely important for making right decisions throughout tsunami warnings procedures. During operational testing of the system a comprehensive analysis of accuracy of the system has been performed. The presentation will present the accuracy analysis of the tsunami forecast and implications for future development and improvements of tsunami forecasting.The rapid development of computing technology allowed us to look into the tsunami impact caused by above hypotheses using high-resolution models with large coverage of Pacific Northwest. With the slab model of MaCrory et al. (2012) (as part of the USGS slab 1.0 model) for the Cascadia earthquake, we tested the above hypotheses to assess the tsunami hazards along the entire U.S. West Coast. The modeled results indicate these hypothetical scenarios may cause runup heights very similar to those observed along Japan's coastline during the 2011 Japan tsunami,. Comparing to a long rupture, the Tohoku-type rupture may cause more serious impact at the adjacent coastline, independent of where it would occur in the Cascadia subduction zone. These findings imply that the Cascadia tsunami hazard may be greater than originally thought.

Titov, V.

2013-12-01

114

Tsunami and Earthquake Research at the USGS  

Science.gov (United States)

This portal provides access to information on United States Geological Survey (USGS) research and resources on tsunamis and earthquakes. Materials include news and events in USGS tsunami research, an overview of the program, and basic information on the life of a tsunami. There are also links to individual research projects. The site also features an extensive set of tsunami animations of real and hypothetical events, and links to VRML models of real and hypothetical events.

2011-07-20

115

Sediment resuspension, transportation and redeposition by tsunami: Example from the 2011 Tohoku-oki tsunami on Sendai and Sanriku shelves  

Science.gov (United States)

Although it is accepted that large tsunami waves impact the sea floor, the response of surface sediments to tsunami is not yet fully understood. Tsunami by the 2011 off the Pacific coast of Tohoku earthquake caused considerable damage to Northeast Japan. Large friction velocity at sea floor by the tsunami waves might agitate and resuspend the surface sediments especially on the shallow shelf. Therefore, formation of event deposits is expected at the wide area off Sanriku region. To understand the phenomena by the 2011 Tohoku-oki tsunami at sea floor, we conducted several surveys on Sendai and Sanriku shelf to forearc area. Large resuspension, transportation and redeposition of shelf mud and sand by the 2011 tsunami was recognized on mid-inner shelf in Sendai Bay. Resuspension of shelf mud made highly turbid water on the shelf. Settling of the suspended mud formed upward-fining graded (sometimes parallel-laminated) mud on the inner-mid shelf. Collapse of such high turbid water mass generated the turbidity currents, and formed turbidite on the outer shelf. Sediment resuspension and turbidity current generation also occurred on Sanriku shelf. Benthic foraminifera assemblage of the uppermost layer of event deposit occurred on the forearc basin floor contained shelf to upper slope species. This also indicates transportation of tsunami-induced gravity flow from shelf to forearc basin. Low gradient of shelf suggests that tsunami is most possible origin of sediment resuspension and turbidity current generation. Therefore, the tsunami-related sediment resuspension occurred at least on shelf to upper slope area, and turbidity currents generated with relation to such sediment resuspension is an important process to transport sediment from shelf to offshore basins.

Ikehara, K.; Usami, K.; Irino, T.

2013-12-01

116

New Activities of the U.S. National Tsunami Hazard Mitigation Program, Mapping and Modeling Subcommittee  

Science.gov (United States)

The U.S. National Tsunami Hazard Mitigation Program (NTHMP) is comprised of representatives from coastal states and federal agencies who, under the guidance of NOAA, work together to develop protocols and products to help communities prepare for and mitigate tsunami hazards. Within the NTHMP are several subcommittees responsible for complimentary aspects of tsunami assessment, mitigation, education, warning, and response. The Mapping and Modeling Subcommittee (MMS) is comprised of state and federal scientists who specialize in tsunami source characterization, numerical tsunami modeling, inundation map production, and warning forecasting. Until September 2012, much of the work of the MMS was authorized through the Tsunami Warning and Education Act, an Act that has since expired but the spirit of which is being adhered to in parallel with reauthorization efforts. Over the past several years, the MMS has developed guidance and best practices for states and territories to produce accurate and consistent tsunami inundation maps for community level evacuation planning, and has conducted benchmarking of numerical inundation models. Recent tsunami events have highlighted the need for other types of tsunami hazard analyses and products for improving evacuation planning, vertical evacuation, maritime planning, land-use planning, building construction, and warning forecasts. As the program responsible for producing accurate and consistent tsunami products nationally, the NTHMP-MMS is initiating a multi-year plan to accomplish the following: 1) Create and build on existing demonstration projects that explore new tsunami hazard analysis techniques and products, such as maps identifying areas of strong currents and potential damage within harbors as well as probabilistic tsunami hazard analysis for land-use planning. 2) Develop benchmarks for validating new numerical modeling techniques related to current velocities and landslide sources. 3) Generate guidance and protocols for the production and use of new tsunami hazard analysis products. 4) Identify multistate collaborations and funding partners interested in these new products. Application of these new products will improve the overall safety and resilience of coastal communities exposed to tsunami hazards.

Wilson, R. I.; Eble, M. C.

2013-12-01

117

Developing Tsunami fragility curves using remote sensing and survey data of the 2010 Chilean Tsunami in Dichato  

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Full Text Available On 27 February 2010, a megathrust earthquake of Mw = 8.8 generated a destructive tsunami in Chile. It struck not only Chilean coast but propagated all the way to Japan. After the event occurred, the post-tsunami survey team was assembled, funded by the Japan Science and Technology Agency (JST, to survey the area severely affected by the tsunami. The tsunami damaged and destroyed numerous houses, especially in the town of Dichato. In order to estimate the structural fragility against tsunami hazard in this area, tsunami fragility curves were developed. Surveyed data of inundation depth and visual inspection of satellite images of Dichato were used to classify the damage to housing. A practical method suitable when there are limitations on available data for numerical simulation or damage evaluation from surveys is presented here. This study is the first application of tsunami fragility curves on the South American Pacific coast and it might be of practical use for communities with similar characteristics along the west Pacific coast. The proposed curve suggests that structures in Dichato will be severely damaged – with a 68% probability – already at 2 m tsunami inundation depth.

E. Mas

2012-08-01

118

Update of the U.S. States and Territories National Tsunami Hazard Assessment: Historical Record and Sources for Waves  

Science.gov (United States)

The NOAA-National Geophysical Data Center (NGDC) and the U.S. Geological Survey (USGS) collaborated to conduct the first qualitative United States tsunami hazard assessment, published in 2008 by the National Tsunami Hazard Mitigation Program (NTHMP). Since that time, significant events such as the 2009 Samoa and 2011 Tohoku tsunamis have affected the U.S. and reinforced the importance of considering all of the evidence when conducting an assessment. In addition, there has been progress in tsunami research that reduces some of the earlier uncertainties. In 2011, the National Academies released their assessment of the U.S. Tsunami Program recommending that NOAA and its NTHMP partners, in collaboration with researchers in social and physical sciences, should complete an initial national assessment of tsunami risk and should institute a periodic assessment of the sources of tsunamis that threaten the United States. Therefore, the NTHMP is updating the national tsunami hazard assessment. Although the second assessment will not be a national probabilistic tsunami hazard assessment, areas where there is progress in this methodology will be presented. As a result, a national tsunami vulnerability and risk assessment is not possible at this time, but examples of ongoing work will be presented. This paper looks at the data sources in the first report, including an examination of the NGDC historical tsunami database that resulted in a qualitative assessment based on the distribution of runup heights and the frequency of tsunami runups. Although tsunami deaths are a measure of risk rather than hazard, the known tsunami deaths were compared with the qualitative assessments based on frequency and amplitude. The 2009 American Samoa tsunami resulted in a change for the U.S. Pacific island territories qualitative tsunami hazard assessment from 'Moderate' to 'High'. The NGDC tsunami database contains reported tsunamis and is therefore limited to written records existing for an area. Some of the uncertainty in the completeness of the written record has been reduced by investigating the history of tide gauges in the different regions. The first tsunami hazard assessment also used the USGS National Seismic Hazard Map (NSHM) databases to partially extend the time interval. These databases are primarily meant to assess earthquakes affecting U.S. possessions and do not include all possible seismogenic tsunami sources in the Pacific and Atlantic Basins. However, the databases make it possible to estimate the rate of occurrence of larger magnitude earthquakes that could generate a tsunami. The USGS NSHM databases are based on tectonic models, and paleoseismic and paleotsunami data. These databases are periodically updated with new research. Inclusion of updated information can reduce uncertainties in tsunami sources such as the Cascadia subduction zone and others.

Dunbar, P. K.; Goldfinger, C.

2013-12-01

119

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

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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.

Garry Rogers

2008-01-01

120

Simulation of the trans-oceanic tsunami propagation due to the 1883 Krakatau volcanic eruption  

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Full Text Available The 1883 Krakatau volcanic eruption has generated a destructive tsunami higher than 40 m on the Indonesian coast where more than 36 000 lives were lost. Sea level oscillations related with this event have been reported on significant distances from the source in the Indian, Atlantic and Pacific Oceans. Evidence of many manifestations of the Krakatau tsunami was a subject of the intense discussion, and it was suggested that some of them are not related with the direct propagation of the tsunami waves from the Krakatau volcanic eruption. Present paper analyzes the hydrodynamic part of the Krakatau event in details. The worldwide propagation of the tsunami waves generated by the Krakatau volcanic eruption is studied numerically using two conventional models: ray tracing method and two-dimensional linear shallow-water model. The results of the numerical simulations are compared with available data of the tsunami registration.

B. H. Choi

2003-01-01

 
 
 
 
121

Development of tsunami early warning systems and future challenges  

Directory of Open Access Journals (Sweden)

Full Text Available Fostered by and embedded in the general development of information and communications technology (ICT, the evolution of tsunami warning systems (TWS shows a significant development from seismic-centred to multi-sensor system architectures using additional sensors (e.g. tide gauges and buoys for the detection of tsunami waves in the ocean.

Currently, the beginning implementation of regional tsunami warning infrastructures indicates a new phase in the development of TWS. A new generation of TWS should not only be able to realise multi-sensor monitoring for tsunami detection. Moreover, these systems have to be capable to form a collaborative communication infrastructure of distributed tsunami warning systems in order to implement regional, ocean-wide monitoring and warning strategies.

In the context of the development of the German Indonesian Tsunami Early Warning System (GITEWS and in the EU-funded FP6 project Distant Early Warning System (DEWS, a service platform for both sensor integration and warning dissemination has been newly developed and demonstrated. In particular, standards of the Open Geospatial Consortium (OGC and the Organization for the Advancement of Structured Information Standards (OASIS have been successfully incorporated.

In the FP7 project Collaborative, Complex and Critical Decision-Support in Evolving Crises (TRIDEC, new developments in ICT (e.g. complex event processing (CEP and event-driven architecture (EDA are used to extend the existing platform to realise a component-based technology framework for building distributed tsunami warning systems.

J. Wächter

2012-06-01

122

Probability-Based Design Criteria of the ASCE 7 Tsunami Loads and Effects Provisions (Invited)  

Science.gov (United States)

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 scenarios in the historical record, and should properly be based on the underlying seismicity of subduction zones. Therefore, Probabilistic Tsunami Hazard Analysis (PTHA) consistent with source seismicity must be performed in addition to consideration of historical event scenarios. A method of Probabilistic Tsunami Hazard Analysis has been established that is generally consistent with Probabilistic Seismic Hazard Analysis in the treatment of uncertainty. These new tsunami design zone maps will define the coastal zones where structures of greater importance would be designed for tsunami resistance and community resilience. Structural member acceptability criteria will be based on performance objectives for a 2,500-year Maximum Considered Tsunami. The approach developed by the ASCE Tsunami Loads and Effects Subcommittee of the ASCE 7 Standard would result in the first national unification of tsunami hazard criteria for design codes reflecting the modern approach of Performance-Based Engineering.

Chock, G.

2013-12-01

123

Combined effects of tectonic and landslide-generated Tsunami Runup at Seward, Alaska during the Mw 9.2 1964 earthquake  

Science.gov (United States)

We apply a recently developed and validated numerical model of tsunami propagation and runup to study the inundation of Resurrection Bay and the town of Seward by the 1964 Alaska tsunami. Seward was hit by both tectonic and landslide-generated tsunami waves during the Mw 9.2 1964 mega thrust earthquake. The earthquake triggered a series of submarine mass failures around the fjord, which resulted in land sliding of part of the coastline into the water, along with the loss of the port facilities. These submarine mass failures generated local waves in the bay within 5 min of the beginning of strong ground motion. Recent studies estimate the total volume of underwater slide material that moved in Resurrection Bay to be about 211 million m3 (Haeussler et al. in Submarine mass movements and their consequences, pp 269-278, 2007). The first tectonic tsunami wave arrived in Resurrection Bay about 30 min after the main shock and was about the same height as the local landslide-generated waves. Our previous numerical study, which focused only on the local land slide generated waves in Resurrection Bay, demonstrated that they were produced by a number of different slope failures, and estimated relative contributions of different submarine slide complexes into tsunami amplitudes (Suleimani et al. in Pure Appl Geophys 166:131-152, 2009). This work extends the previous study by calculating tsunami inundation in Resurrection Bay caused by the combined impact of landslide-generated waves and the tectonic tsunami, and comparing the composite inundation area with observations. To simulate landslide tsunami runup in Seward, we use a viscous slide model of Jiang and LeBlond (J Phys Oceanogr 24(3):559-572, 1994) coupled with nonlinear shallow water equations. The input data set includes a high resolution multibeam bathymetry and LIDAR topography grid of Resurrection Bay, and an initial thickness of slide material based on pre- and post-earthquake bathymetry difference maps. For simulation of tectonic tsunami runup, we derive the 1964 coseismic deformations from detailed slip distribution in the rupture area, and use them as an initial condition for propagation of the tectonic tsunami. The numerical model employs nonlinear shallow water equations formulated for depth-averaged water fluxes, and calculates a temporal position of the shoreline using a free-surface moving boundary algorithm. We find that the calculated tsunami runup in Seward caused first by local submarine landslide-generated waves, and later by a tectonic tsunami, is in good agreement with observations of the inundation zone. The analysis of inundation caused by two different tsunami sources improves our understanding of their relative contributions, and supports tsunami risk mitigation in south-central Alaska. The record of the 1964 earthquake, tsunami, and submarine landslides, combined with the high-resolution topography and bathymetry of Resurrection Bay make it an ideal location for studying tectonic tsunamis in coastal regions susceptible to underwater landslides. ?? 2010 Springer Basel AG.

Suleimani, E.; Nicolsky, D. J.; Haeussler, P. J.; Hansen, R.

2011-01-01

124

Integrated warning system for tsunami and storm surges in China  

International Nuclear Information System (INIS)

Tsunami and storm surges result in unusual oscillation of seal level, flooding the coastal zones and constitute the major marine disasters in China. Damage by storm surges occurs frequently. According to statistics there are 14 storm surge events exceeding 1 every year on the average. Six of them are typhoon surges and the other eight are extra-tropical surges. In general, in China, there is one severe disaster of storm surge every two years. Monitoring, forecasting and warning for storm surges, including the drop of water level, are the major part of the operational oceanographic services in China. Such a warning system has been set up and is operated by the State Oceanic Administration since 1974. The results of the historical study of tsunami in the last few years pointed out that the anomaly of sea level generated by tele-tsunamis originating in the Pacific Ocean Basin is less than 30 cm on the mainland coast, but local tsunami in the China Seas can be very dangerous. For example, more than 50,000 people were killed by a tsunami in Taiwan and in Taiwan Strait in 1781. It resulted in more deaths than any other tsunami in recorded history. However, the frequency of tsunami disaster is very low for the coast of China, averaging only one every 100 years. It is impossible to set up an independent tsunami warning system in China. It is more practical to set up an integrated warning system on tsunami and on storm surges consisting of: A sea level observing network with real time sea level data acquisition capability; A monitoring system of weather causing the storm surges and of seismic stations monitoring tsunamigenic earthquakes; A tidal prediction scheme for operational use; A forecasting scheme for storm surges and tsunami analysis; The means for warning dissemination. (author). 8 refs, 4 figs, 3 tabs

1989-08-04

125

Generation and Propagation of Tsunami by a Moving Realistic Curvilinear Slide Shape with Variable Velocities in Linearized Shallow-Water Wave Theory  

Directory of Open Access Journals (Sweden)

Full Text Available The process of tsunami evolution during its generation under the effect of the variable velocities of realistic submarine landslides based on a two-dimensional curvilinear slide model is investigated. Tsunami generation from submarine gravity mass flows is described in three stages. The first stage represented by a rapid curvilinear down and uplift faulting with rise time. The second stage represented by a unilaterally propagation in the positive x direction to a significant length to produce curvilinear two-dimensional models represented by a depression slump, and a displaced accumulation slide model. The last stage represented by the time variation in the velocity of the accumulation slide (block slide. By using transforms method, Laplace in time and Fourier in space, tsunami waveforms within the frame of the linearized shallow water theory for constant water depth are analyzed analytically for the movable source model. Effect of the water depths on the amplification factor of the tsunami generation by the submarine slump and slide for different propagation lengths and widths has been studied and the results are plotted. Comparison of tsunami peak amplitudes is discussed for different propagation lengths, widths and water depths. In addition, we demonstrated the tsunami propagation waveforms after the slide stops moving at different propagation times.

Sarwat Nageeb Hanna

2010-07-01

126

Generating tsunami risk knowledge at community level as a base for planning and implementation of risk reduction strategies  

Digital Repository Infrastructure Vision for European Research (DRIVER)

More than 4 million Indonesians live in tsunami-prone areas along the southern and western coasts of Sumatra, Java and Bali. Although a Tsunami Early Warning Center in Jakarta now exists, installed after the devastating 2004 tsunami, it is essential to develop tsunami risk knowledge within the exposed communities as a basis for tsunami disaster management. These communities need to implement risk reduction strategies to mitigate potential consequences.

The major aims of t...

Wegscheider, S.; Post, J.; Zosseder, K.; Mu?ck, M.; Strunz, G.; Riedlinger, T.; Muhari, A.; Anwar, H. Z.

2011-01-01

127

Local Bathymetry and Shelf Resonance Effects Observed for the Near-field Tsunami Generated by the 2010, Mw 8.8, Maule Earthquake  

Science.gov (United States)

The Chilean coast has been hit by several far- and near-field tsunamis, for instance the last recent destructive tsunami devastating the Chilean shore was caused by the 2010 Mw 8.8, Maule earthquake. Several long-period waves were recorded away by DART buoys and local eyewitness and field surveys also confirm that incoming waves have hit the shore several hours after the leading wave arrival time. In addition, few published numerical modeling of the Maule near-field tsunami show trapping waves and amplification of the energy over the continental shelf. To better understand the origin of the tsunami wave trains and the continental shelf features as a potential responsible of resonance, we perform tsunami modeling by improving the earthquake source parameters modeling. We generate realistic 3D static displacement of the seafloor to be used as input for tsunami passive generation, propagation and runup estimates along the shore. We meshed the seismogenic contact zone between the Nazca and Sudamerica plates along the Maule region, through a 3D surface. The co-seismic slip distribution solution published for the Maule earthquake were used to model the runup, and trapped waves were observed on the numerical simulations. To further study the hypothesis of that a large magnitude earthquake may generate same kind of hydrodynamic effect, such as, successive tsunami wave trains, we modeled several hypothetical physical-based slip distributions for a Mw 8.8 earthquake rupture. At every subfault we used the Okada's point-source formula to compute the co-seismic static 3D displacement field. Preliminary results, show that a complex geometry of the slab have important effects on the vertical static displacements. We are currently evaluating the tsunami propagation for these hypothetical earthquakes, the study include understanding specific aspects related to local bathymetry, and hydrodynamic effects, among which, flow direction, directivity, reflection, diffraction, focusing/defocussing of water waves, and local shelf resonance.

Ruiz-Paredes, J. A.; Fuentes, M.; Riquelme, S.; Contreras Reyes, E.; Ruiz, S.; Maksymowicz, A.

2013-12-01

128

Revision of the Portuguese catalog of tsunamis  

Directory of Open Access Journals (Sweden)

Full Text Available Catastrophic tsunamis are described in historical sources for all regions around the Gulf of Cadiz, at least since 60 BC. Most of the known events are associated with moderate to large earthquakes and among them the better studied is 1 November 1755. We present here a review of the events which effects, on the coasts of the Portuguese mainland and Madeira Island, are well described in historical documents or have been measured by tide gauges since the installation of these instruments. For a few we include new relevant information for the assessment of the tsunami generation or effects, and we discard events that are included in existing compilations but are not supported by quality historical sources or instrumental records. We quote the most relevant quantitative descriptions of tsunami effects on the Portuguese coast, including in all pertinent cases a critical review of the coeval sources, to establish a homogenous event list. When available, instrumental information is presented. We complement all this information with a summary of the conclusions established by paleo-tsunami research.

M. A. Baptista

2009-01-01

129

Earthquake and submarine landslide tsunamis: how can we tell the difference? (Invited)  

Science.gov (United States)

Several major recent events have shown the tsunami hazard from submarine mass failures (SMF), i.e., submarine landslides. In 1992 a small earthquake triggered landslide generated a tsunami over 25 meters high on Flores Island. In 1998 another small, earthquake-triggered, sediment slump-generated tsunami up to 15 meters high devastated the local coast of Papua New Guinea killing 2,200 people. It was this event that led to the recognition of the importance of marine geophysical data in mapping the architecture of seabed sediment failures that could be then used in modeling and validating the tsunami generating mechanism. Seabed mapping of the 2004 Indian Ocean earthquake rupture zone demonstrated, however, that large, if not great, earthquakes do not necessarily cause major seabed failures, but that along some convergent margins frequent earthquakes result in smaller sediment failures that are not tsunamigenic. Older events, such as Messina, 1908, Makran, 1945, Alaska, 1946, and Java, 2006, all have the characteristics of SMF tsunamis, but for these a SMF source has not been proven. When the 2011 tsunami struck Japan, it was generally assumed that it was directly generated by the earthquake. The earthquake has some unusual characteristics, such as a shallow rupture that is somewhat slow, but is not a 'tsunami earthquake.' A number of simulations of the tsunami based on an earthquake source have been published, but in general the best results are obtained by adjusting fault rupture models with tsunami wave gauge or other data so, to the extent that they can model the recorded tsunami data, this demonstrates self-consistency rather than validation. Here we consider some of the existing source models of the 2011 Japan event and present new tsunami simulations based on a combination of an earthquake source and an SMF mapped from offshore data. We show that the multi-source tsunami agrees well with available tide gauge data and field observations and the wave data from offshore buoys, and that the SMF generated the large runups in the Sanriku region (northern Tohoku). Our new results for the 2011 Tohoku event suggest that care is required in using tsunami wave and tide gauge data to both model and validate earthquake tsunami sources. They also suggest a potential pitfall in the use of tsunami waveform inversion from tide gauges and buoys to estimate the size and spatial characteristics of earthquake rupture. If the tsunami source has a significant SMF component such studies may overestimate earthquake magnitude. Our seabed mapping identifies other large SMFs off Sanriku that have the potential to generate significant tsunamis and which should be considered in future analyses of the tsunami hazard in Japan. The identification of two major SMF-generated tsunamis (PNG and Tohoku), especially one associated with a M9 earthquake, is important in guiding future efforts at forecasting and mitigating the tsunami hazard from large megathrust plus SMF events both in Japan and globally.

Tappin, D. R.; Grilli, S. T.; Harris, J.; Geller, R. J.; Masterlark, T.; Kirby, J. T.; Ma, G.; Shi, F.

2013-12-01

130

Field survey of the March 28, 2005 Nias-Simeulue earthquake and Tsunami  

Science.gov (United States)

On the evening of March 28, 2005 at 11:09 p.m. local time (16:09 UTC), a large earthquake occurred offshore of West Sumatra, Indonesia. With a moment magnitude (Mw) of 8.6, the event caused substantial shaking damage and land level changes between Simeulue Island in the north and the Batu Islands in the south. The earthquake also generated a tsunami, which was observed throughout the source region as well as on distant tide gauges. While the tsunami was not as extreme as the tsunami of December 26th, 2004, it did cause significant flooding and damage at some locations. The spatial and temporal proximity of the two events led to a unique set of observational data from the earthquake and tsunami as well as insights relevant to tsunami hazard planning and education efforts. ?? 2010 Springer Basel AG.

Borrero, J. C.; McAdoo, B.; Jaffe, B.; Dengler, L.; Gelfenbaum, G.; Higman, B.; Hidayat, R.; Moore, A.; Kongko, W.; Lukijanto; Peters, R.; Prasetya, G.; Titov, V.; Yulianto, E.

2011-01-01

131

Tsunami hazard assessment for the Azores archipelago: a historical review  

Science.gov (United States)

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 Azores is mostly driven from the events triggered by distant earthquakes and local earthquakes and landslides. In this context, were identified 12 tsunami events. In another context, it were identified 6 events associated with coastal areas flooding due to floods and/or extreme weather phenomena, hypothetically identified as meteotsunamis. It should be stressed that, despite the differences associated with their triggering mechanisms, both the tsunamis generated by geological factors and those related to atmospheric phenomena may have similar impact. Although the absence of reports identifying tsunamis associated with volcanic activity, the eruptive history of the Azores active volcanoes shows high magnitude eruptions with considerable tsunamigenic potential.

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

2010-05-01

132

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

Science.gov (United States)

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.

Cummins, P. R.; Burbdige, D.

2005-05-01

133

NOAA/WEST COAST AND ALASKA TSUNAMI WARNING CENTER ATLANTIC OCEAN RESPONSE CRITERIA  

Directory of Open Access Journals (Sweden)

Full Text Available West Coast/Alaska Tsunami Warning Center (WCATWC response criteria for earthquakes occurring 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 pre- computed 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.

Paul Whitmore

2009-01-01

134

MEtop - a top FCNC event generator  

CERN Document Server

We present a new Monte Carlo generator for Direct top and Single top production via flavour-changing neutral currents (FCNC). This new tool calculates the cross section and generates events with Next-to-Leading order precision for the Direct top process and Leading-Order precision for all other FCNC single top processes. A set of independent dimension six FCNC operators has been implemented - including four-fermion operators - where at least one top-quark is present in the interaction.

Coimbra, Rita; Santos, Rui; Won, Miguel

2013-01-01

135

EVENT GENERATOR FOR RHIC SPIN PHYSICS  

Energy Technology Data Exchange (ETDEWEB)

This volume archives the reports from the RIKEN BNL Research Center workshop on ``Event Generator for RHIC Spin Physics II'' held during the week March 15, 1999 at Brookhaven National Laboratory. It was the second meeting on the subject following a first one in last September. This workshop has been initiated to establish a firm collaboration between theorists and experimentalists involved in RHIC spin physics with the aim of developing a reliable, high-precision event generator for RHIC spin physics. Needless to say, adequate event generators are indispensable tools for high energy physics programs in general, especially in the process of: planning the experimental programs; developing algorithms to extract the physics signals of interest; estimating the background in the extracted results, and connecting the final particle kinematics to the fundamental i.e. partonic level processes. Since RHIC is the first polarized collider, dedicated efforts are required to obtain a full-fledged event generator which describes spin dependent reactions in great detail.

SAITO,N.; SCHAEFER,A.

1999-03-15

136

EVENT GENERATOR FOR RHIC SPIN PHYSICS  

International Nuclear Information System (INIS)

This volume archives the reports from the RIKEN BNL Research Center workshop on ''Event Generator for RHIC Spin Physics II'' held during the week March 15, 1999 at Brookhaven National Laboratory. It was the second meeting on the subject following a first one in last September. This workshop has been initiated to establish a firm collaboration between theorists and experimentalists involved in RHIC spin physics with the aim of developing a reliable, high-precision event generator for RHIC spin physics. Needless to say, adequate event generators are indispensable tools for high energy physics programs in general, especially in the process of: planning the experimental programs; developing algorithms to extract the physics signals of interest; estimating the background in the extracted results, and connecting the final particle kinematics to the fundamental i.e. partonic level processes. Since RHIC is the first polarized collider, dedicated efforts are required to obtain a full-fledged event generator which describes spin dependent reactions in great detail

1999-03-15

137

A comparison between two inundation models for the 25 Ooctober 2010 Mentawai Islands Tsunami  

Science.gov (United States)

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.

Huang, Z.; Borrero, J. C.; Qiu, Q.; Hill, E. M.; Li, L.; Sieh, K. E.

2011-12-01

138

The Redwood Coast Tsunami Work Group: a unique organization promoting earthquake and tsunami resilience on California's North Coast  

Science.gov (United States)

The Northern California counties of Del Norte, Humboldt, and Mendocino account for over 30% of California's coastline and is one of the most seismically active areas of the contiguous 48 states. The region is at risk from earthquakes located on- and offshore and from tsunamis generated locally from faults associated with the Cascadia subduction zone (CSZ) and from distant sources elsewhere in the Pacific. In 1995 the California Geological Survey (CGS) published a scenario for a CSZ earthquake that included both strong ground shaking effects and a tsunami. As a result of the scenario, the Redwood Coast Tsunami Work Group (RCTWG), an organization of government agencies, tribes, service groups, academia and the private sector, was formed to coordinate and promote earthquake and tsunami hazard awareness and mitigation in the three-county region. The RCTWG and its member agencies projects include education/outreach products and programs, tsunami hazard mapping, signage and siren planning. Since 2008, RCTWG has worked with the California Emergency Management Agency (Cal EMA) in conducting tsunami warning communications tests on the North Coast. In 2007, RCTWG members helped develop and carry out the first tsunami training exercise at FEMA's Emergency Management Institute in Emmitsburg, MD. The RCTWG has facilitated numerous multi-agency, multi-discipline coordinated exercises, and RCTWG county tsunami response plans have been a model for other regions of the state and country. Eight North Coast communities have been recognized as TsunamiReady by the National Weather Service, including the first National Park the first State Park and only tribe in California to be so recognized. Over 500 tsunami hazard zone signs have been posted in the RCTWG region since 2008. Eight assessment surveys from 1993 to 2010 have tracked preparedness actions and personal awareness of earthquake and tsunami hazards in the county and additional surveys have tracked public awareness and tourist concerns about tsunami hazard signs. Over the seventeen-year period covered by the surveys, the percent with houses secured to foundations has increased from 58 to 84 percent, respondents aware of a local tsunami hazard increased from 51 to 89 percent and knowing what the Cascadia subduction zone is from 16 to 57 percent. In 2009, the RCTWG was recognized by the Western States Seismic Policy Council (WSSPC) with an award for innovation and in 2010, the RCTWG-sponsored class "Living on Shaky Ground" was awarded WSSPC's overall Award in Excellence. The RCTWG works closely with CGS and Cal EMA on a number of projects including tsunami mapping, evacuation zone planning, siren policy, tsunami safety for boaters, and public education messaging. Current projects include working with CGS to develop a "playbook" tsunami mapping product to illustrate the expected effects from a range of tsunami source events and assist local governments in focusing future response actions to reflect the range expected impacts from distant source events. Preparedness efforts paid off on March 11, 2011 when a tsunami warning was issued for the region and significant damage occurred in harbor regions of Del Norte County and Mendocino County. Full-scale evacuations were carried out in a coordinated manner and the majority of the commercial fishing fleet in Crescent City was able to exit the harbor before the tsunami arrived.

Dengler, L.; Henderson, C.; Larkin, D.; Nicolini, T.; Ozaki, V.

2012-12-01

139

Test of TEDA, Tsunami Early Detection Algorithm  

Science.gov (United States)

Tsunami detection in real-time, both offshore and at the coastline, plays a key role in Tsunami Warning Systems since it provides so far the only reliable and timely proof of tsunami generation, and is used to confirm or cancel tsunami warnings previously issued on the basis of seismic data alone. Moreover, in case of submarine or coastal landslide generated tsunamis, which are not announced by clear seismic signals and are typically local, real-time detection at the coastline might be the fastest way to release a warning, even if the useful time for emergency operations might be limited. TEDA is an algorithm for real-time detection of tsunami signal on sea-level records, developed by the Tsunami Research Team of the University of Bologna. The development and testing of the algorithm has been accomplished within the framework of the Italian national project DPC-INGV S3 and the European project TRANSFER. The algorithm is to be implemented at station level, and it is based therefore only on sea-level data of a single station, either a coastal tide-gauge or an offshore buoy. TEDA's principle is to discriminate the first tsunami wave from the previous background signal, which implies the assumption that the tsunami waves introduce a difference in the previous sea-level signal. Therefore, in TEDA the instantaneous (most recent) and the previous background sea-level elevation gradients are characterized and compared by proper functions (IS and BS) that are updated at every new data acquisition. Detection is triggered when the instantaneous signal function passes a set threshold and at the same time it is significantly bigger compared to the previous background signal. The functions IS and BS depend on temporal parameters that allow the algorithm to be adapted different situations: in general, coastal tide-gauges have a typical background spectrum depending on the location where the instrument is installed, due to local topography and bathymetry, while offshore buoys are mainly characterized by the astronomical tide and white noise. TEDA has been tested on specific events recorded by Adak Island tide-gauge, in Alaska, and by DART buoys, located offshore Alaska, thanks to the collaboration with NCTR of PMEL/NOAA (NOAA Centre for Tsunami Research of Pacific and Marine Environmental Laboratory/National Oceanic and Atmospheric Administration). Three methods for the characterization of the background signal have been tested and compared with different characterization settings, in order to find the most appropriate calibration. To evaluate the algorithm performance, different indicators have been taken into account, such as the number of false detections, the number of events detected, the delay of detection and the duration of the tsunami alert state. Particular attention has been reserved to the number of false detections, which compromise heavily the reliability of a detection algorithm and undermine the usefulness of the algorithm itself. The method to test TEDA is presented here and is proposed as an example of procedure to evaluate the performance of the tsunami detection algorithms used in the Tsunami Early Warning Systems practice.

Bressan, Lidia; Tinti, Stefano

2010-05-01

140

EVENT GENERATOR FOR RHIC SPIN PHYSICS.  

Energy Technology Data Exchange (ETDEWEB)

This volume archives the reports from the RIKEN BNL Research Center workshop on ''Event Generator for RHIC Spin Physics II'' held during the week March 15, 1999 at Brookhaven National Laboratory. It was the second meeting on the subject following a first one in last September. This workshop has been initiated to establish a firm collaboration between theorists and experimentalists involved in RHIC spin physics with the aim of developing a reliable, high-precision event generator for RHIC spin physics. Needless to say, adequate event generators are indispensible tools for high energy physics programs in general, especially in the process of: planning the experimental programs, developing algorithms to extract the physics signals of interest, estimating the background in the extracted results, and connecting the final particle kinematics to the fundamental i.e. partonic level processes. Since RHIC is the first polarized collider, dedicated efforts are required to obtain a full-fledged event generator which describes spin dependent reactions in great detail. The RHIC spin project will be in the transition from R&D and construction phase to operation phase in the year 2000. As soon as data will be available, it should be analysed, interpreted and compared with theoretical predictions to extract its physical significance. Without mutual understanding between theorists and experimentalists on the technical details, it is hard to perform detailed comparisons in a consistent framework. The importance of this fact has been recognized especially during the analyses of hadron induced reactions observed at CERN, Fermilab and DESY. Since the use of event generator is indispensible for the analyses, it should be developed in a way that both experimentalists and theorists can agree upon.

SAITO,N.; SCHAEFER,A.

1999-03-15

 
 
 
 
141

Tsunamis in Cuba?  

International Nuclear Information System (INIS)

Cuba as neo tectonics structure in the southern of the North American plate had three tsunamis. One of them [local] occurred in the Central-Northern region [1931.10.01, Nortecubana fault], the other was a tele tsunami [1755.11.01, in the SW of the Iberian Peninsula] that hit the Bay of Santiago de Cuba, and the third took place at 1867.11.18, by the regional source of Virgin Islands, which produced waves in the Eastern Cuban region. This tsunami originated to the NE of Puerto Rico in 1918.10.11, with another earthquake of equal magnitude and at similar coordinates, produced a tsunami that did not affect Cuba. Information on the influence of regional tsunami in 1946.08.08 of the NE of the Dominican Republic [Matanzas] in Northwestern Cuba [beaches Guanabo-Baracoa] is contrary to expectations with the waves propagation. The local event of 1939.08.15 attributed to Central- Northern Cuba [Cayo Frances with M = 8.1] does not correspond at all with the maximum magnitude of earthquakes in this region and the potential of the Nortecubana fault. Tsunamis attributed to events such as 1766.06.11 and 1932.02.03 in the Santiago de Cuba Bay are not reflected in the original documents from experts and eyewitnesses. Tsunamis from Jamaica have not affected the coasts of Cuba, despite its proximity. There is no influence in Cuba of tsunamigenic sources of the southern and western parts of the Caribbean, or the Gulf of Mexico. Set out the doubts as to the influence of tsunamis from Haiti and Dominican Republic at Guantanamo Bay which is closer to and on the same latitude, and spatial orientation than the counterpart of Santiago de Cuba, that had impact. The number of fatalities by authors in the Caribbean is different and contradictory. (Author) 76 refs.

2011-01-01

142

Dynamics of tsunami waves  

Digital Repository Infrastructure Vision for European Research (DRIVER)

The life of a tsunami is usually divided into three phases: the generation (tsunami source), the propagation and the inundation. Each phase is complex and often described separately. A brief description of each phase is given. Model problems are identified. Their formulation is given. While some of these problems can be solved analytically, most require numerical techniques. The inundation phase is less documented than the other phases. It is shown that methods based on Smoo...

Dias, Fre?de?ric; Dutykh, Denys

2006-01-01

143

Note on the 1964 Alaska Tsunami Generation by Horizontal Displacements of Ocean Bottom. Numerical Modeling of the Runup in Chenega Cove, Alaska  

Science.gov (United States)

A numerical model of the wave dynamics in Chenega Cove, Alaska during the historic M w 9.2 megathrust earthquake is presented. During the earthquake, locally generated waves of unknown origin were identified at the village of Chenega, located in the western part of Prince William Sound. The waves appeared shortly after the shaking began and swept away most of the buildings while the shaking continued. We model the tectonic tsunami in Chenega Cove assuming different tsunami generation processes. Modeled results are compared with eyewitness reports and an observed runup. Results of the numerical experiments let us claim the importance of including both vertical and horizontal displacement into the 1964 tsunami generation process. We also present an explanation for the fact that arrivals of later waves in Chenega were unnoticed.

Nicolsky, D. J.; Suleimani, E. N.; Hansen, R. A.

2013-09-01

144

Status of Monte-Carlo Event Generators  

International Nuclear Information System (INIS)

Recent progress on general-purpose Monte-Carlo event generators is reviewed with emphasis on the simulation of hard QCD processes and subsequent parton cascades. Describing full final states of high-energy particle collisions in contemporary experiments is an intricate task. Hundreds of particles are typically produced, and the reactions involve both large and small momentum transfer. The high-dimensional phase space makes an exact solution of the problem impossible. Instead, one typically resorts to regarding events as factorized into different steps, ordered descending in the mass scales or invariant momentum transfers which are involved. In this picture, a hard interaction, described through fixed-order perturbation theory, is followed by multiple Bremsstrahlung emissions off initial- and final-state and, finally, by the hadronization process, which binds QCD partons into color-neutral hadrons. Each of these steps can be treated independently, which is the basic concept inherent to general-purpose event generators. Their development is nowadays often focused on an improved description of radiative corrections to hard processes through perturbative QCD. In this context, the concept of jets is introduced, which allows to relate sprays of hadronic particles in detectors to the partons in perturbation theory. In this talk, we briefly review recent progress on perturbative QCD in event generation. The main focus lies on the general-purpose Monte-Carlo programs HERWIG, PYTHIA and SHERPA, which will be the workhorses for LHC phenomenology. A detailed description of the physics models included in these generators can be found in (8). We also discuss matrix-element generators, which provide the parton-level input for general-purpose Monte Carlo.

2011-04-11

145

Tsunami Hazard Assessment along the Coast of Oman from Near- and Far-field Tectonic Sources  

Science.gov (United States)

Coastal areas of Oman are exposed to tsunami threat associated with earthquakes generated in two major subduction zones, namely Makran and Sumatra. Both zones were responsible of triggering tsunamis that reached/impacted Oman coast. The Mw8.1 earthquake event of 1945, occurred in Makran zone, has caused a tsunami that was reported to affect the coast of Oman. The Mw9.2 Indian Ocean event of 2004 triggered a tsunami that was recorded in various tide-gauges stations of Oman with wave amplitude reaching ~1.7m in the port of Salalah. This work aims to assess tsunami hazard along the Oman coast considering both deterministic and probabilistic approaches. Deterministic approach uses particular source scenarios (most credible and/or worst case) from Makran and Sumatra subduction zones and computes the tsunami coastal impact through numerical modeling of expected waveforms, maximum wave heights distribution, and site-specific inundations. While, probabilistic approach includes the contribution of small and large sources and employs the probabilistic seismic hazard assessment together with the numerical modeling to evaluate the likelihood that a certain level of tsunami threat is exceeded at a certain location of Oman coast within a certain period of time. We present deterministic results in terms of regional scale distribution of maximum wave heights, tsunami waveforms computation, and inundation maps for a selected coastal area. For probabilistic assessment, we derive 250- and 500-years probability hazard exceedance maps and hazard curves for the Oman coast. The hazard maps consist of computing the likelihood that tsunami waves exceed a specific amplitude for the entire coast of Oman, and the hazard curves describe the variation of cumulative probabilities as function of wave amplitudes at some critical coastal points. Finally, we discuss the usefulness of obtained results for tsunami mitigation in Oman. Keywords: Tsunami, Oman, Deterministic approach, Probabilistic approach.

El-Hussain, Issa; Baptista, Maria; Omira, Rachid; Al-Rawas, Ghazi; Deif, Ahmed; Al-Habsi, Zaid; Al-Jabri, Khalifa

2014-05-01

146

A short history of tsunami research and countermeasures in Japan  

Digital Repository Infrastructure Vision for European Research (DRIVER)

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...

Shuto, Nobuo; Fujima, Koji

2009-01-01

147

1854-2014: 160 years of far-field tsunami detection and warning  

Science.gov (United States)

The first scientific study of a tsunami as generated by a distant earthquake can be traced to Bache [1856] who correctly identified waves from the 1854 Nankai earthquake on California tidal gauges. We will review developments in the study of the relationship between earthquake source and far field tsunami, with their logical application to distant warning. Among the principal milestones, we discuss Hochstetter's [1869] work on the 1868 Arica tsunami, Jaggar's real-time, but ignored, warning of the 1923 Kamchatka tsunami in Hawaii, his much greater success with the 1933 Showa Sanriku event, the catastrophic 1946 Aleutian event, which led to the implementation of PTWC, the 1960 events in Hilo, and the 1964 Alaska tsunami, which led to the development of the A[now N]TWC. From the scientific standpoint, we will review the evolution of our attempts to measure the seismic source (in practice its seismic moment), always faster, and at always lower frequencies, culminating in the W-phase inversion, heralded by Kanamori and co-workers in the wake of the Sumatra disaster. Specific problems arise from events violating scaling laws, such as the so-called "tsunami earthquakes", and we will review methodologies to recognize them in real time, such as energy-to-moment ratios. Finally, we will discuss briefly modern technologies aimed at directly detecting the tsunami independently of the seismic source.

Okal, Emile

2014-05-01

148

MEtop – a top FCNC event generator  

International Nuclear Information System (INIS)

In this work we present a new Monte Carlo generator for Direct top and Single top production via flavour-changing neutral currents (FCNC). This new tool calculates the cross section and generates events with Next-to-Leading order precision for the Direct top process and Leading-Order precision for all other FCNC single top processes. A set of independent dimension six FCNC operators has been implemented – including four-fermion operators – where at least one top-quark is present in the interaction

2013-07-24

149

Event generation with SHERPA 1.1  

Digital Repository Infrastructure Vision for European Research (DRIVER)

In this paper the current release of the Monte Carlo event generator Sherpa, version 1.1, is presented. Sherpa is a general-purpose tool for the simulation of particle collisions at high-energy colliders. It contains a very flexible tree-level matrix-element generator for the calculation of hard scattering processes within the Standard Model and various new physics models. The emission of additional QCD partons off the initial and final states is described through a parton-shower model. To co...

2009-01-01

150

NLO-QCD Event Generators in GRACE  

International Nuclear Information System (INIS)

Automatic Feynman-amplitude calculation system, GRACE, has been extended to treat next-to-leading order (NLO) QCD calculations. Matrix elements of loop diagrams as well as those of tree level ones can be generated using the GRACE system. A soft/collinear singularity is treated using a leading-log subtraction method. Higher order re-summation of the soft/collinear correction by the parton shower method is combined with the NLO matrix element without any double-counting in this method. An example of the event generator for W+ jet and di-photon processes are given for demonstrating a validity of this method. (author)

2008-07-01

151

Holocene tsunamis from Mount Etna and the fate of Israeli Neolithic communities  

Science.gov (United States)

Field evidence reveals that the Neolithic village of Atlit-Yam (Israeli coast) was destroyed in an event which also caused the sudden death of tens of inhabitants. Archaeological evidence and numerical simulations support the notion that the village was destroyed, ~8.3 ka B.P., by a tsunami triggered by a known Holocene flank collapse of Mt. Etna volcano (Italy). The filling of a water well within the village confirms inundation by a tsunami wave train and a sediment layer, composed of a clayed-sandy matrix and other detritus including reworked marine sediment, indicates tsunami inundation. This scenario shows that tsunamis generated by sector collapses from coastal volcanoes can seriously threaten near-shore settlements thousands of kilometres distant from the tsunami source.

Pareschi, Maria Teresa; Boschi, Enzo; Favalli, Massimiliano

2007-08-01

152

TSUNAMI CATALOG AND VULNERABILITY OF MARTINIQUE (LESSER ANTILLES, FRANCE  

Directory of Open Access Journals (Sweden)

Full Text Available In addition to meteorological hazards (hurricanes, heavy rainfalls, long-period swells, etc., the Caribbean Islands are vulnerable to geological hazards such as earthquakes, landslides and volcanic eruptions caused by the complex tectonic activity and interactions in the region. Such events have generated frequently local or regional tsunamis, which often have affected the island of Martinique in the French West Indies. Over the past centuries, the island has been struck by destructive waves associated with local or regional events - such as those associated with the eruption of the Saint-Vincent volcano in 1902 and by tsunamis of distant origin as that generated by the 1755 Lisbon earthquake.The present study includes a classification of tsunamis that have affected Martinique since its discovery in 1502. It is based on international tsunami catalogs, historical accounts, and previous scientific studies and identifies tsunamigenic areas that could potentially generate destructive waves that could impact specific coastal areas of Martinique Island. The potential threat from tsunamis has been greatly increasing because of rapid urban expansion of coastal areas and development of tourism on the island.

Roger, J.

2010-01-01

153

Tsunami Research driven by Survivor Observations: Sumatra 2004, Tohoku 2011 and the Lituya Bay Landslide (Plinius Medal Lecture)  

Science.gov (United States)

The 10th anniversary of the 2004 Indian Ocean tsunami recalls the advent of tsunami video recordings by eyewitnesses. The tsunami of December 26, 2004 severely affected Banda Aceh along the North tip of Sumatra (Indonesia) at a distance of 250 km from the epicenter of the Magnitude 9.0 earthquake. The tsunami flow velocity analysis focused on two survivor videos recorded within Banda Aceh more than 3km from the open ocean. The exact locations of the tsunami eyewitness video recordings were revisited to record camera calibration ground control points. The motion of the camera during the recordings was determined. The individual video images were rectified with a direct linear transformation (DLT). Finally a cross-correlation based particle image velocimetry (PIV) analysis was applied to the rectified video images to determine instantaneous tsunami flow velocity fields. The measured overland tsunami flow velocities were within the range of 2 to 5 m/s in downtown Banda Aceh, Indonesia. The March 11, 2011, magnitude Mw 9.0 earthquake off the coast of Japan caused catastrophic damage and loss of life. Fortunately many survivors at evacuation sites recorded countless tsunami videos with unprecedented spatial and temporal coverage. Numerous tsunami reconnaissance trips were conducted in Japan. This report focuses on the surveys at selected tsunami eyewitness video recording locations along Japan's Sanriku coast and the subsequent tsunami video image analysis. Locations with high quality survivor videos were visited, eyewitnesses interviewed and detailed site topography scanned with a terrestrial laser scanner (TLS). The analysis of the tsunami videos followed the four step procedure developed for the analysis of 2004 Indian Ocean tsunami videos at Banda Aceh. Tsunami currents up to 11 m/s were measured in Kesennuma Bay making navigation impossible. Further tsunami height and runup hydrographs are derived from the videos to discuss the complex effects of coastal structures on inundation and outflow flow velocities. Tsunamis generated by landslides and volcanic island collapses account for some of the most catastrophic events. On July 10, 1958, an earthquake Mw 8.3 along the Fairweather fault triggered a major subaerial landslide into Gilbert Inlet at the head of Lituya Bay on the south coast of Alaska. The landslide impacted the water at high speed generating a giant tsunami and the highest wave runup in recorded history. This event was observed by eyewitnesses on board the sole surviving fishing boat, which managed to ride the tsunami. The mega-tsunami runup to an elevation of 524 m caused total forest destruction and erosion down to bedrock on a spur ridge in direct prolongation of the slide axis. A cross-section of Gilbert Inlet was rebuilt in a two dimensional physical laboratory model. Particle image velocimetry (PIV) provided instantaneous velocity vector fields of decisive initial phase with landslide impact and wave generation as well as the runup on the headland. Three dimensional source and runup scenarios based on real world events are physically modeled in the NEES tsunami wave basin (TWB) at Oregon State University (OSU). The measured landslide and tsunami data serve to validate and advance numerical landslide tsunami models. This lecture encompasses multi-hazard aspects and implications of recent tsunami and cyclonic events around the world such as the November 2013 Typhoon Haiyan (Yolanda) in the Philippines.

Fritz, Hermann M.

2014-05-01

154

Sediment Transport, Mixing, and Erosion by an Impact Generated Tsunami: Gulf of Carpentaria, Australia  

Science.gov (United States)

The Gulf of Carpentaria contains two impact crater candidates, the 18 km Tabban and 12 km Kanmare craters. We have identified an impact ejecta layer in cores from the Gulf of Carpentaria containing probable shocked quartz, magnetic iron oxide impact spherules with a bimodal size distribution, vitreous Ca phosphate with a few percent Na2O and MgO(whitlockite?), lithified glauconite microfossil casts with partial calcite rims, and other impact ejecta. The quartz grains have at least 3 different orientations of closely spaced linear fractures only a few micrometers apart (probable planar deformation features). As we have imaged these planar features using a scanning electron microscope, the shocked nature of the grains must be confirmed by measuring crystallographic directions on conventional thin sections. We found impact ejecta at the deepest depth of our sampling in six different cores (Table 1). The ejecta layer extends up into the top 2 cm of every core. However, the thickness of the layer in cm (Obs) is much greater than that predicted by simple air fall models(1) (Calc) of ejecta thickness as a function of kilometers from the nearest crater candidate (Dist). The concentration of impact ejecta is much too high to explain the layer thicknesses by bioturbation of a formerly thin layer of ejecta. Thus, we interpret these layers as a megatsunami deposit from the impact event that formed Tabban and Kanmare craters. As supporting evidence, core MD31 (also from the Gulf of Carpentaria) has 14C ages in the top 70 cm that do not increase uniformly with increasing depth, but instead fluctuate in a random manner(2). Although the dominant ostracod assemblage is marine, MD32 has a large percentage of reworked lacustrine fossils and broken shell in the top 38 cm(3). Many Holocene marine sequences from the deepest part of the Gulf of Carpentaria contain reworked lacustrine fossils(4). Because the Gulf of Carpentaria was a lake until around 10,400 yr B.P., the mixture of fossil types is suggestive of erosion and redeposition by a tsunami or other means. Table 1. Impact Ejecta in Deep Sea Cores Latitude Long. Core Calc Obs Dist -16.850 139.885 VC01 232 >245 31 -16.501 139.890 VC23 052 >69 69 -15.659 138.010 BC48 7.4 >20 151 -12.313 138.979 MD32 0.3 >37 471 -10.789 138.719 MD29 0.1 >32 641 -9.8395 135.348 GC04 0.1 >61 846 References. 1. G. S. Collins, H. J. Melosh, R. A. Marcus, Meteoritics and Planetary Science (2004). 2. J. M. Reeves, A. R. Chivas, A. Garcia, P. D. Deckker, Palaeogeography, Palaeoclimatology, Palaeoecology 246, 163 (2007). 3. J. M. Reeves, A. R. Chivas, S. Holt, M. J. J. Couapel, B. G. Jones, Quaternary International , (in press). 4. P. De Deckker, Palaeogeography, Palaeoclimatology, Palaeoecology 62, 463 (1988).

Abbott, D. H.; Tester, E. W.; Meyers, C. A.; Breger, D.; Chivas, A. R.

2007-12-01

155

Hydrodynamics of impact-induced tsunami over the Martian ocean  

Science.gov (United States)

Large bodies of liquid water ranging from lakes to oceans have been hypothesized to have occupied the surface of ancient Mars episodically. Such inferences have been founded largely on geomorphological observations of putative shoreline features during the period ranging from the 1980s to the early 2000s. High-resolution satellite images obtained during various Mars missions conducted since the early 2000s have enabled detailed sedimentological studies. One phenomenon that might leave sedimentological traces of the purported Martian paleo-oceans is a bolide impact and consequent generation of large tsunami waves. Numerical modeling of impact-induced tsunami waves on a hypothesized northern plains paleo-ocean was performed to elucidate their potential propagation characteristics on Mars, including the ranges of wave height and velocity. When considering a tsunami triggered by a 50 km-diameter impact cratering event, the offshore and shore-zone wave heights respectively reached 40-50 m and 120 m. In the same test scenario, the tsunami wave velocity reached 20 m/s near the crater and 16 m/s at the shore zone. The wave height and velocity in highly cratered regions, such as Arabia Terra, tend to be relatively low because tsunami inundation is diffused by impact crater rims existing along the tsunami passage.

Iijima, Yasutaka; Goto, Kazuhisa; Minoura, Koji; Komatsu, Goro; Imamura, Fumihiko

2014-05-01

156

What is the fault that has generated the earthquake on 8 September 1905 in Calabria, Italy? Source models compared by tsunami data  

Science.gov (United States)

The earthquake that the 8 September 1905 hit Calabria in southern Italy was the second Italian earthquake for magnitude in the last century. It destroyed many villages along the coast of the Gulf of Sant'Eufemia, caused more than 500 fatalities and has also generated a tsunami with non-destructive effects. The historical reports tell us that the tsunami caused major damage in the villages of Briatico, Bivona, Pizzo and Vibo Marina, located in the south part of the Sant'Eufemia gulf and minor damage to Tropea and to Scalea, this one being village located about 100 km far from the epicenter. Other reports include accounts of fishermen at sea during the tsunami. Further, the tsunami is visible on tide gauge records in Messina, Sicily, in Naples and in Civitavecchia, a harbour located to the north of Rome (Platania, 1907) In spite of the attention devoted by researchers to this case, until now, like for other tsunamigenic Italian earthquakes, the genetic structure of the earthquake is still not identified and debate is still open. In this context, tsunami simulations can provide contributions useful to find the source model more consistent with observational data. This approach was already followed by Piatanesi and Tinti (2002), who carried out numerical simulations of tsunamis from a number of local sources. In the last decade studies on this seismogenic area were int ensified resulting in new estimates for the 1905 earthquake magnitude (7.1 according to the CPTI11 catalogue) and in the suggestion of new source models. By using an improved tsunami simulation model, more accurate bathymetry data, this work tests the source models investigated by Piatanesi and Tinti (2002) and in addition the new fault models proposed by Cucci and Tertulliani (2010) and by Loreto et al. (2013). The simulations of the tsunami are calculated by means of the code, UBO-TSUFD, that solves the linear equations of Navier-Stokes in approximation of shallow water with the finite-difference technique, while the initial conditions are calculated via Okada's formula. The key-result used to test the models against the data is the maximum height of the tsunami calculated close to the shore at a minimum depth of 5m corrected using the values of the initial coseismic field deformation.

Pagnoni, Gianluca; Armigliato, Alberto; Tinti, Stefano; Loreto, Maria Filomena; Facchin, Lorenzo

2014-05-01

157

Next generation multi-particle event generators for the MSSM  

International Nuclear Information System (INIS)

We present a next generation of multi-particle Monte Carlo (MC) Event generators for LHC and ILC for the MSSM, namely the three program packages Madgraph/MadEvent, WHiZard/O'Mega and Sherpa/Amegic++. The interesting but difficult phenomenology of supersymmetric models at the upcoming colliders demands a corresponding complexity and maturity from simulation tools. This includes multi-particle final states, reducible and irreducible backgrounds, spin correlations, real emission of photons and gluons, etc., which are incorporated in the programs presented here. The framework of a model with such a huge particle content and as complicated as the MSSM makes strenuous tests and comparison of codes inevitable. Various tests show agreement among the three different programs; the tables of cross sections produced in these tests may serve as a future reference for other codes. Furthermore, first MSSM physics analyses performed with these programs are presented here. (orig.)

2005-01-01

158

Next Generation Multi-particle event generators for the MSSM  

CERN Multimedia

We present a next generation of multi-particle Monte Carlo (MC) Event generators for LHC and ILC for the MSSM, namely the three program packages Madgraph/MadEvent, WHiZard/O'Mega and Sherpa/Amegic++. The interesting but difficult phenomenology of supersymmetric models at the upcoming colliders demands a corresponding complexity and maturity from simulation tools. This includes multi-particle final states, reducible and irreducible backgrounds, spin correlations, real emission of photons and gluons, etc., which are incorporated in the programs presented here. The framework of a model with such a huge particle content and as complicated as the MSSM makes strenuous tests and comparison of codes inevitable. Various tests show agreement among the three different programs; the tables of cross sections produced in these tests may serve as a future reference for other codes. Furthermore, first MSSM physics analyses performed with these programs are presented here.

Reuter, J; Kilian, W; Krauss, F; Ohl, T; Plehn, T; Rainwater, D L; Schumann, S

2005-01-01

159

Does the source of the 28 December 1908 Messina Straits tsunami coincide with the earthquake source? Hints from tsunami numerical modelling  

Science.gov (United States)

Together with eastern Sicily and Calabria, the Messina Straits is the region with the highest tsunamigenic occurrence rate in Italy. Tsunami catalogues indicate that the tsunami hazard in the Messina Straits is related to both local and remote sources, where remote refers to sources placed just outside the Straits (i.e. southern Tyrrhenian and eastern Sicily), and also to sources found at great distances, like the Western Hellenic Arc. Moreover, the Straits has historically been impacted by tsunamis generated by earthquakes as well as by landslides. The most recent and probably most famous event of catastrophic dimensions is the 28 December 1908 tsunami which followed a M=7.1-7.2 earthquake that razed to the ground the cities of Messina and Reggio Calabria, placed on the two opposite sides of the Straits. The effects of the tsunami are described in a large number of contemporary reports and have been recently revised by different authors to produce a set of data comprising run-up measurements, time delays between the earthquake occurrence and the first tsunami arrival, and first tsunami polarities in several coastal places located inside and outside the Straits. Similarly to other historical tsunamis contained in the Italian tsunami catalogue and following large earthquakes, the source for the 1908 event is debated, both as regards the earthquake and the tsunami. Several fault models have been proposed through the years based on the inversion or analysis of different kind of data. But usually the fault models retrieved by inverting macroseismic, seismological or geodetic data do not reproduce satisfactorily the tsunami observations. Recently it has been proposed (Billi et al., 2008) that a submarine landslide and not the earthquake was the responsible for the tsunami generation. In the framework of the EU-funded project TRANSFER (Tsunami Risk and Strategies For the European Region), coordinated by the Department of Physics of the University of Bologna, Italy, and of the Italian DPC-INGV-S1 project, we simulate numerically the generation, propagation and impact of the tsunami waves generated by earthquake and landslide sources taken from the available literature, with the goal of understanding which of the hypotheses proposed so far best reproduces the tsunami first arrival polarities, the first arrival timings and the run-up heights. From the modelling point of view, the initial condition for earthquake-generated tsunamis is taken to coincide with the vertical coseismic displacement and is computed through the analytical formulas by Okada (1992). The generation by landslides is simulated by means of the Lagrangian numerical model UBO-BLOCK2, developed and maintained by the Tsunami Research Team at the University of Bologna, Italy. The finite difference model UBO-TSUFD, developed by the same research group, is used to compute the tsunami propagation and impact.

Armigliato, A.; Tinti, S.; Zaniboni, F.; Pagnoni, G.; Tonini, R.; Gallazzi, S.; Manucci, A.

2009-04-01

160

Event generation with SHERPA 1.1  

Energy Technology Data Exchange (ETDEWEB)

In this paper the current release of the Monte Carlo event generator Sherpa, version 1.1, is presented. Sherpa is a general-purpose tool for the simulation of particle collisions at high-energy colliders. It contains a very flexible tree-level matrix-element generator for the calculation of hard scattering processes within the Standard Model and various new physics models. The emission of additional QCD partons off the initial and final states is described through a parton-shower model. To consistently combine multi-parton matrix elements with the QCD parton cascades the approach of Catani, Krauss, Kuhn and Webber is employed. A simple model of multiple interactions is used to account for underlying events in hadron-hadron collisions. The fragmentation of partons into primary hadrons is described using a phenomenological cluster-hadronization model. A comprehensive library for simulating tau-lepton and hadron decays is provided. Where available form-factor models and matrix elements are used, allowing for the inclusion of spin correlations; effects of virtual and real QED corrections are included using the approach of Yennie, Frautschi and Suura.

Gleisberg, T.; Hoche, Stefan.; Krauss, F.; Schoenherr, M.; Schumann, S.; Siegert, F.; Winter, J.

2008-12-18

 
 
 
 
161

Event generation with SHERPA 1.1  

CERN Document Server

In this paper the current release of the Monte Carlo event generator Sherpa, version 1.1, is presented. Sherpa is a general-purpose tool for the simulation of particle collisions at high-energy colliders. It contains a very flexible tree-level matrix-element generator for the calculation of hard scattering processes within the Standard Model and various new physics models. The emission of additional QCD partons off the initial and final states is described through a parton-shower model. To consistently combine multi-parton matrix elements with the QCD parton cascades the approach of Catani, Krauss, Kuhn and Webber is employed. A simple model of multiple interactions is used to account for underlying events in hadron--hadron collisions. The fragmentation of partons into primary hadrons is described using a phenomenological cluster-hadronisation model. A comprehensive library for simulating tau-lepton and hadron decays is provided. Where available form-factor models and matrix elements are used, allowing for th...

Gleisberg, T; Krauss, F; Schoenherr, M; Schumann, S; Siegert, F; Winter, J

2009-01-01

162

Event generation with SHERPA 1.1  

International Nuclear Information System (INIS)

In this paper the current release of the Monte Carlo event generator Sherpa, version 1.1, is presented. Sherpa is a general-purpose tool for the simulation of particle collisions at high-energy colliders. It contains a very flexible tree-level matrix-element generator for the calculation of hard scattering processes within the Standard Model and various new physics models. The emission of additional QCD partons off the initial and final states is described through a parton-shower model. To consistently combine multi-parton matrix elements with the QCD parton cascades the approach of Catani, Krauss, Kuhn and Webber is employed. A simple model of multiple interactions is used to account for underlying events in hadron-hadron collisions. The fragmentation of partons into primary hadrons is described using a phenomenological cluster-hadronization model. A comprehensive library for simulating tau-lepton and hadron decays is provided. Where available form-factor models and matrix elements are used, allowing for the inclusion of spin correlations; effects of virtual and real QED corrections are included using the approach of Yennie, Frautschi and Suura

2008-01-01

163

Event generation with SHERPA 1.1  

Science.gov (United States)

In this paper the current release of the Monte Carlo event generator Sherpa, version 1.1, is presented. Sherpa is a general-purpose tool for the simulation of particle collisions at high-energy colliders. It contains a very flexible tree-level matrix-element generator for the calculation of hard scattering processes within the Standard Model and various new physics models. The emission of additional QCD partons off the initial and final states is described through a parton-shower model. To consistently combine multi-parton matrix elements with the QCD parton cascades the approach of Catani, Krauss, Kuhn and Webber is employed. A simple model of multiple interactions is used to account for underlying events in hadron-hadron collisions. The fragmentation of partons into primary hadrons is described using a phenomenological cluster-hadronisation model. A comprehensive library for simulating tau-lepton and hadron decays is provided. Where available form-factor models and matrix elements are used, allowing for the inclusion of spin correlations; effects of virtual and real QED corrections are included using the approach of Yennie, Frautschi and Suura.

Gleisberg, T.; Höche, S.; Krauss, F.; Schönherr, M.; Schumann, S.; Siegert, F.; Winter, J.

2009-02-01

164

The UBO-TSUFD tsunami inundation model: validation and application to a tsunami case study focused on the city of Catania, Italy  

Digital Repository Infrastructure Vision for European Research (DRIVER)

Nowadays numerical models are a powerful tool in tsunami research since they can be used (i) to reconstruct modern and historical events, (ii) to cast new light on tsunami sources by inverting tsunami data and observations, (iii) to build scenarios in the frame of tsunami mitigation plans, and (iv) to produce forecasts of tsunami impact and inundation in systems of early warning. In parallel with the general recognition of the importance of numerical tsunami simulations, the...

Tinti, S.; Tonini, R.

2013-01-01

165

The UBO-TSUFD tsunami inundation model: validation and application to a tsunami case study focused on the city of Catania, Italy  

Digital Repository Infrastructure Vision for European Research (DRIVER)

Nowadays numerical models are a powerful tool in tsunami research since they can be used (i) to reconstruct modern and historical events, (ii) to cast new light on tsunami sources by inverting tsunami data and observations, (iii) to build scenarios in the frame of tsunami mitigation plans, and (iv) to produce forecasts of tsunami impact and inundation in systems of early warning. In parallel with the general recognition of the importance of numerical tsunami simulations, the demand has grown ...

Tinti, S.; Tonini, R.

2013-01-01

166

Simulations of Tsunami Triggered by the 1883 Krakatau Volcanic Eruption: Implications for Tsunami Hazard in the South China Sea  

Science.gov (United States)

The 1883 Krakatau eruption in Indonesia is one of the largest recorded volcanic eruptions in recent history. The associated tsunami claimed about 36,000 lives and recorded run-up heights up to 30 m along the coastal regions in the Sunda Straits between the Indian Ocean and the South China Sea. Our study aims to better understand the generation and propagation mechanisms of this volcano-induced tsunami through modeling quantitatively the tsunami triggering processes at the source region. Comparison of non-linear simulations using the Cornell Multi-grid Coupled Tsunami Model (COMCOT) with observations reveals that a donut-shape 'hole and ring' initial condition for the tsunami source is able to explain the key characteristics of the observed tsunami: A 'hole' of about 6 km in diameter and 270 m in depth corresponds to the collapse of the Krakatau volcano on August 27, 1883, while a 'ring' of uplift corresponds to the deposition of the erupted volcanic materials. We found that the shallowness and narrowness of the entrance pathway of the Sunda Straits limited the northward transfer of the tsunami energy from the source region into the South China Sea. Instead, the topographic and bathymetric characteristics favored the southward transfer of the energy into the Indian Ocean. This might explain why Sri Lanka and India suffered casualties from this event, while areas inside the South China Sea, such as Singapore, did not record significant tsunami signals. Modeling results further suggest that the shallow topography of the surrounding islands around the Krakatau source region might have contributed to a reduction in maximum run-up heights in the coastal regions of the Sunda Straits.

Tan, Y.; Lin, J.

2013-12-01

167

TSUNAMI HAZARD IN NORTHERN VENEZUELA  

Directory of Open Access Journals (Sweden)

Full Text Available Based on LANDSAT ETM and Digital Elevation Model (DEM data derived by the Shuttle Radar Topography Mission (SRTM, 2000 of the coastal areas of Northern Venezuela were investigated in order to detect traces of earlier tsunami events. Digital image processing methods used to enhance LANDSAT ETM imageries and to produce morphometric maps (such as hillshade, slope, minimum and maximum curvature maps based on the SRTM DEM data contribute to the detection of morphologic traces that might be related to catastrophic tsunami events. These maps combined with various geodata such as seismotectonic data in a GIS environment allow the delineation of coastal regions with potential tsunami risk. The LANDSAT ETM imageries merged with digitally processed and enhanced SRTM data clearly indicate areas that might be prone by flooding in case of catastrophic tsunami events.

B. Theilen-Willige

2006-01-01

168

Elegent—An elastic event generator  

Science.gov (United States)

Although elastic scattering of nucleons may look like a simple process, it presents a long-lasting challenge for theory. Due to missing hard energy scale, the perturbative QCD cannot be applied. Instead, many phenomenological/theoretical models have emerged. In this paper we present a unified implementation of some of the most prominent models in a C++ library, moreover extended to account for effects of the electromagnetic interaction. The library is complemented with a number of utilities. For instance, programs to sample many distributions of interest in four-momentum transfer squared, t, impact parameter, b, and collision energy s. These distributions at ISR, Spp¯S, RHIC, Tevatron and LHC energies are available for download from the project web site. Both in the form of ROOT files and PDF figures providing comparisons among the models. The package includes also a tool for Monte-Carlo generation of elastic scattering events, which can easily be embedded in any other program framework.

Kašpar, J.

2014-03-01

169

The earthquake and tsunami of 1865 November 17: evidence for far-field tsunami hazard from Tonga  

Science.gov (United States)

Historical reports of an earthquake in Tonga in 1865 November identify it as the only event from that subduction zone which generated a far-field tsunami observable without instruments. Run-up heights reached 2 m in Rarotonga and 80 cm in the Marquesas Islands. Hydrodynamic simulations require a moment of 4 × 1028 dyn cm, a value significantly larger than previous estimates of the maximum size of earthquake to be expected at the Tonga subduction zone. This warrants an upwards re-evaluation of the tsunami risk from Tonga to the Cook Islands and the various Polynesian chains, which had hitherto been regarded as minor.

Okal, Emile A.; Borrero, José; Synolakis, Costas E.

2004-04-01

170

Tsunami Simulations for Regional Sources in the South China and Adjoining Seas  

Science.gov (United States)

The tsunami potential from sources located in the South China Sea and its adjoining basins, Sulu and Sulawesi Seas, is examined. Tsunami numerical modeling was performed using the MOST code [Titov and Synolakis, 1998] for a number of possible earthquake scenarios at the various local subduction zones. For the Sulawesi Sea, we consider the events of 1918 at the Mindanao subduction zone, and the 1996 at the Northern end of the Makassar Strait. For the Sulu Sea, we consider a scenario inspired by the 1948 Panay earthquake (because of the fractured nature of the plate system in those areas, it is not feasible to consider much larger earthquakes). Tsunami simulations of these events show that the tsunami is contained within the relevant marginal seas and does not penetrate significantly the greater South China Basin. However, tsunami hazard that could cause significant damage was found for the Eastern coast of Borneo. Farther North, we consider as worst case scenarios events reaching 10**29 dyn*cm with rupture lengths of 400 km, both off Luzon Island and, under a slightly different geometry, off the Luzon Straits separating the Philippines and Taiwan. These scenarios show very significant hazard to all coastlines bordering the South China Sea, including Indochina and Borneo. Finally, two landslide-generated tsunami scenarios are presented, inspired from the event of 14 February 1934 off the Luzon Strait, and the presumably Holocene Brunei mega-slide.

Kalligeris, N.; Okal, E. A.; Synolakis, C. E.

2009-04-01

171

Identification of Forerunners and Transmission of Energy to Tsunami Waves Generated by Instanteneous Ground Motion on a Non-Uniformly Sloping Beach  

Digital Repository Infrastructure Vision for European Research (DRIVER)

The problem of generation and propagation of tsunami waves is mainly focused on plane beach, there are very few analytical works where wave generation is considered on non-uniformly sloping beach and as a result those works might have failed to capture important facts which are influenced by bottom-slope of the beach. Some researchers provided solution to the forced long linear waves but on a beac...

Arghya Bandyopadhyay

2013-01-01

172

Puerto Rico Tsunami Warning and Mitigation Program-LANTEX 09 Survey  

Science.gov (United States)

Tsunami warning, assessment, education, mitigation and preparedness efforts seek to reduce losses related to tsunamis in Puerto Rico (PR). The PR Seismic Network (PRSN) works with governmental agencies and local communities to implement these tsunami hazard risk reduction programs. The Caribbean has a a history of destructive tsunamis such as Virgin Islands (1867), PR (1918) and Dominican Republic (1946). Tsunamis originating near PR are a near-field hazard for as they can reach coastal areas within minutes of a generating event. Sources for regional and tele tsunamis have been identified. To mitigate these risks to communities, the PR Tsunami Warning and Mitigation Program (PRTWMP) was established in 2000 with funding from FEMA, the University of Puerto Rico (UPR) and the PR State Emergency Management Agency (PRSEMA). With the support of NTHMP and TsunamiReady (TR), PR continues to seek to mitigate possible tsunami damages and increase community resilience by helping communities meet the TR guidelines by providing them inundation maps, helping them develop evacuation maps and emergency plans, assisting them with community outreach efforts and conducting evacuation drills. Currently 6 of 44 tsunami threatened communities in PR have been recognized as TsunamiReady. As part of this process, the PRSN, PRSEMA and various communities participated in the LANTEX 2009 tsunami exercise. This exercise took place on April 2, 2009 and was based on a scenario in which an earthquake northeast of PR generates a major tsunami which impacts PR and the USVI and threatens the states along the continental US eastern coast. The municipality of Mayagüez, a TsunamiReady community since 2006, participated in the exercise by activating its Emergency Operations Center , conducting evacuation drills in schools located within its tsunami exposed area, and activating its warning siren. This presentation highlights findings of UPRM social scientists collaborating with the PRTWMP who conducted a sample survey of residents of the Mayagüez tsunami evacuation area to serve as an assessment of the effectiveness of TsunamiReady outreach efforts and of the drill's warning efforts. 166 20-30 minute interviews were conducted during the month of April. Questions explored residents' perceptions of coastal hazards they may face; knowledge about tsunamis and how to react to them; use of mass media to obtain information about potential hazards; tsunami preparation efforts, including knowledge of the existence and location of assembly areas; and whether and how they received and understood the drill's warning messages. The sample's answers to the risk perception questions is compared to those obtained for the same questions from a sample of residents of storm surge areas in 8 municipalities along PR's west coast. This allows comparing tsunami hazard awareness among individuals exposed to the Tsunami Ready program efforts with that of residents of municipalities that are not part of it. This effort serves as an example of the multidisciplinary collaboration between physical and social scientists needed to increase the effectiveness and value of scientific knowledge as a tool to mitigate damages from natural hazards.

Diaz, W.; von Hillebrandt-Andrade, C.

2009-12-01

173

A hydro-acoustic solution to the local tsunami warning problem  

Science.gov (United States)

We demonstrate the potential for using the spectral content of T-phases from earthquakes to identify events involves a component of splay faulting. There is significant evidence indicating that splay faulting explains extreme local tsunamis in events with more moderate distant tsunamis. For example, the distant tsunami from the Dec. 26, 2004 Megathrust is fully explained by the primary rupture. However, the local tsunami was significantly (3 to 4x larger) than predicted and 10 minutes early. The discrepancy can be explained by significant rupture along a splay fault approximately 90km west of Banda Aceh. The secondary rupture produces a high amplitude, short wavelength tsunami that is not resolvable seismically, as the softer sediments would produce significantly (1/40th to 1/100th) less seismic radiation than the primary rupture. However, the secondary rupture appears to generate observable hydroacoustic signals. The shallow rupture of the secondary source results in less anelastic attenuation, producing a shallower spectral slope of the T- phase than the much larger primary rupture. The observed signal is the combination of the weaker shallow secondary rupture and the much larger (and deeper) primary rupture. At low frequencies, the primary rupture dominates the spectral shape. At higher frequencies, the weaker shallow source predominates. We are able resolve the dual rupture in the case of Northern Sumatra. This is significant because, in the 378 earthquakes analyzed, only three events showed this pattern for more than 50 seconds; two of those events had anomalously large local Tsunamis: Northern Sumatra and Nias Island. The third event was an Mw 7.6 strike slip fault. It is thus likely that a significantly curved T-phase spectrum is indicative of secondary (possibly splay) sources, and increased likelihood of local tsunamis. A prototype system to identify the signatures of the secondary faulting has been developed and installed at the Pacific Tsunami Warning Center in Ewa Beach, HI.

Salzberg, D. H.

2008-12-01

174

Tsunami Awareness  

Medline Plus

Full Text Available ... But they are most often caused by an earthquake where there's a sudden displacement of the ocean ... warning signs of an incoming tsunami: a strong earthquake that causes difficulty standing; a rapid rise or ...

175

Tsunami Awareness  

Medline Plus

Full Text Available ... 100 feet high, traveling at 400 miles per hour. This ocean monster is known as a tsunami ... force. The series of waves may continue for hours. The first one may not be the last ...

176

Tsunami Awareness  

Medline Plus

Full Text Available ... floor. When that happens, there's a transfer of energy from the seafloor to the ocean, causing waves ... or the largest. For your safety, know the potential warning signs of an incoming tsunami: a strong ...

177

Tsunami Awareness  

Medline Plus

Full Text Available ... a series of ocean waves caused by any large and sudden disturbance of the sea surface. Tsunamis ... water along the coast may recede noticeably. A large wall of turbulent water, called a "bore," may ...

178

TSUNAMI HAZARD AND TOTAL RISK IN THE CARIBBEAN BASIN  

Digital Repository Infrastructure Vision for European Research (DRIVER)

Deadly western North Atlantic Ocean tsunami events in the last centuries have occurred along the east coast of Canada, the United States, most Caribbean islands, and the North Atlantic Coast of South America. The catastrophic Indian Ocean tsunami of 2004 reminded natural hazards managers that tsunami risk is endemic to all oceans. Total Risk is defined as hazard (frequency of tsunami events) times measures of elements at risk (human exposure) times measures of vulnerability (preparedness) in ...

2010-01-01

179

A deterministic analysis of tsunami hazard and risk for the southwest coast of Sri Lanka  

Science.gov (United States)

This paper describes a multi-scenario, deterministic analysis carried out as a pilot study to evaluate the tsunami hazard and risk distribution in the southwest coast of Sri Lanka. The hazard and risk assessment procedure adopted was also assessed against available field records of the impact of the Indian Ocean tsunami in 2004. An evaluation of numerically simulated nearshore tsunami amplitudes corresponding to ‘maximum-credible' scenarios from different subduction segments in the Indian Ocean surrounding Sri Lanka suggests that a seismic event similar to that generated the tsunami in 2004 can still be considered as the ‘worst-case' scenario for the southwest coast. Furthermore, it appears that formation of edge waves trapped by the primary waves diffracting around the southwest significantly influences the nearshore tsunami wave field and is largely responsible for relatively higher tsunami amplitudes in certain stretches of the coastline under study. The extent of inundation from numerical simulations corresponding to the worst-case scenario shows good overall agreement with the points of maximum penetration of inundation from field measurements in the aftermath of the 2004 tsunami. It can also be seen that the inundation distribution is strongly influenced by onshore topography. The present study indicates that the mean depth of inundation could be utilised as a primary parameter to quantify the spatial distribution of the tsunami hazard. The spatial distribution of the risk of the tsunami hazard to the population and residential buildings computed by employing the standard risk formula shows satisfactory correlation with published statistics of the affected population and the damage to residential property during the tsunami in 2004.

Wijetunge, J. J.

2014-05-01

180

Developing tsunami fragility curves based on the satellite remote sensing and the numerical modeling of the 2004 Indian Ocean tsunami in Thailand  

Digital Repository Infrastructure Vision for European Research (DRIVER)

The 2004 Indian Ocean tsunami damaged and destroyed numerous buildings and houses in Thailand. Estimation of tsunami impact to buildings from this event and evaluation of the potential risks are important but still in progress. The tsunami fragility curve is a function used to estimate the structural fragility against tsunami hazards. This study was undertaken to develop fragility curves using visual inspection of high-resolution satellite images (IKONOS) taken before and after tsunami events...

Suppasri, A.; Koshimura, S.; Imamura, F.

2011-01-01

 
 
 
 
181

First applications of the HIPSE event generator  

International Nuclear Information System (INIS)

The predictions of an event generator, HIPSE (Heavy-Ion Phase-Space Exploration), dedicated to the description of nuclear collisions in the intermediate energy range, are compared with experimental data collected by the INDRA and INDRA-ALADIN collaborations. Special emphasis is put on the kinematical characteristics of fragments and light particles at all impact parameters for the system Xe+Sn between 25 and 80 MeV/u. Considering the kinematical characteristics of the fragments, we have shown that the collective motion finds its origin both in the intrinsic motion of the nucleon and in the relative momentum between the two partners of the reaction suggesting a fragmentation process with a strong memory of the entrance channel. Moreover, the model gives information on the phase space explored during the collision as for example pre-equilibrium emission. It also allows a direct access of the partition at freeze-out (in terms of excitation energy, angular momentum, impact parameter...) before secondary decay

2003-11-05

182

First applications of the HIPSE event generator  

Energy Technology Data Exchange (ETDEWEB)

The predictions of an event generator, HIPSE (Heavy-Ion Phase-Space Exploration), dedicated to the description of nuclear collisions in the intermediate energy range, are compared with experimental data collected by the INDRA and INDRA-ALADIN collaborations. Special emphasis is put on the kinematical characteristics of fragments and light particles at all impact parameters for the system Xe+Sn between 25 and 80 MeV/u. Considering the kinematical characteristics of the fragments, we have shown that the collective motion finds its origin both in the intrinsic motion of the nucleon and in the relative momentum between the two partners of the reaction suggesting a fragmentation process with a strong memory of the entrance channel. Moreover, the model gives information on the phase space explored during the collision as for example pre-equilibrium emission. It also allows a direct access of the partition at freeze-out (in terms of excitation energy, angular momentum, impact parameter...) before secondary decay.

Van Lauwe, A.; Lacroix, D.; Durand, D. [Caen Univ., LPC (IN2P3-CNRS/ENSI), 14 - Caen (France)

2003-07-01

183

Historic Tsunami in the Indian Ocean  

Science.gov (United States)

The 2004 Boxing Day Tsunami dramatically highlighted the need for a better understanding of the tsunami hazard in the Indian Ocean. One of the most important foundations on which to base such an assessment is knowledge of tsunami that have affected the region in the historical past. We present a summary of the previously published catalog of Indian Ocean tsunami and the results of a preliminary search of archival material held at the India Records Office at the British Library in London. We demonstrate that in some cases, normal tidal movements and floods associated with tropical cyclones have been erroneously listed as tsunami. We summarise interesting archival material for tsunami that occurred in 1945, 1941, 1881, 1819, 1762 and a tsunami in 1843 not previously identified or reported. We also note the recent discovery, by a Canadian team during a post-tsunami survey following the 2004 Boxing Day Tsunami, of archival evidence that the Great Sumatra Earthquake of 1833 generated a teletsunami. Open ocean wave heights are calculated for some of the historical tsunami and compared with those of the Boxing Day Tsunami.

Dominey-Howes, D.; Cummins, P. R.; Burbidge, D.

2005-12-01

184

Assessment of Nearshore Hazard due to Tsunami-Induced Currents (Invited)  

Science.gov (United States)

The California Tsunami Program coordinated by CalOES and CGS in cooperation with NOAA and FEMA has begun implementing a plan to increase awareness of tsunami generated hazards to the maritime community (both ships and harbor infrastructure) through the development of in-harbor hazard maps, offshore safety zones for boater evacuation, and associated guidance for harbors and marinas before, during and following tsunamis. The hope is that the maritime guidance and associated education and outreach program will help save lives and reduce exposure of damage to boats and harbor infrastructure. An important step in this process is to understand the causative mechanism for damage in ports and harbors, and then ensure that the models used to generate hazard maps are able to accurately simulate these processes. Findings will be used to develop maps, guidance documents, and consistent policy recommendations for emergency managers and port authorities and provide information critical to real-time decisions required when responding to tsunami alert notifications. The goals of the study are to (1) evaluate the effectiveness and sensitivity of existing numerical models for assessing maritime tsunami hazards, (2) find a relationship between current speeds and expected damage levels, (3) evaluate California ports and harbors in terms of tsunami induced hazards by identifying regions that are prone to higher current speeds and damage and to identify regions of relatively lower impact that may be used for evacuation of maritime assets, and (4) determine ';safe depths' for evacuation of vessels from ports and harbors during a tsunami event. This presentation will focus on the results from five California ports and harbors, and will include feedback we have received from initial discussion with local harbor masters and port authorities. This work in California will form the basis for tsunami hazard reduction for all U.S. maritime communities through the National Tsunami Hazard Mitigation Program.

Lynett, P. J.; Borrero, J. C.; Son, S.; Wilson, R. I.; Miller, K.

2013-12-01

185

The Source Mechanism of 1939 Black Sea Tsunami  

Science.gov (United States)

The Black sea is surrounded by Turkey at South, Bulgaria, Romania and Moldovia at west, Russia and Ukraine at North, Georgia at East. The Great Erzincan Earthquake occurred on December 26, 1939 at 23:57 (GMT) in Turkey. This earthquake is remarkable not only because of its devastating casualties (39000), but also because of the tsunami generation in the Black sea [Richter, 1958]. The recorded epicenter coordinates (39.51oE, 39.80oN) was on land and approximately 60 km away from the south coast of the Black sea. The earthquake was shallow (26 km). The surface magnitude was 8 (maximal value for tsunami-generic earthquake in the Black Sea), and intensity of the earthquake was 11-12 [Nikonov, 1997]. Tsunami waves were observed at south coast of the Black sea near Fatsa, Ordu and Giresun towns in Turkey and recorded at North coast near Sebastopol, Yalta, Novorossiysk, Tuapse, and at East near poti and Batumi. The sea receded 50m, and then advanced 20m near Fatsa town. The sea also receded 50-60 m in Giresun, moreover in Ordu, the eyewitnesses at the harbor observed that sea initially was calm, then receded about 15 m. and returned its original position in 5-10 minutes [Altynok and Ersoy, 2000]. The tsunami crossed the Black Sea and was recorded on tide-gauges in Soviet harbors with height 50 cm in Sevastopol and Novorossiysk, and 40 cm in Tuapse. The intensity of this tsunami can be considered as intensity III-V according to new tsunami intensity scale of [Papadopoulos and Imamura, 2001]. Since the epicenter of the earthquake is far from the sea, the source mechanism of this tsunami is uncertain. The wave might have originated by either directly from rupture, or by the secondary fault in the Black sea, or by a submarine landslide triggered by the earthquake. The available data of tide gauge measurements, and observations can be used to compare the model results with different source mechanisms and initial conditions. The initial wave with different assumptions of source mechanisms for 1939 event are used in simulation. The arrival times of the tsunami waves, the initial sign of the wave form, the wave period and the nearshore tsunami amplitudes are computed at selected coastal stations. The computed tsunami records at the coastal locations are compared with the available data. The comparison of the observational, instrumental and numerical data at the shore locations are used for analysis and comparison of the assumed source mechanisms. The probable source mechanism of 1939 Black sea Tsunami is also discussed. Altynok, Y. and _. Ersoy (2000), Tsunamis observed on and near the Turkish coast. Natural Hazards, 21, 185-20. Nikonov, A. A. (1997), Tsunami occurrence on the coasts of the Black Sea and the Sea of Azov. Izvestiya, Physics of Solid Earth, 33, 72 - 87. Papadopoulos, G.A. and F. Imamura (2001), A proposal for a new tsunami intensity scale, Proceedings of International Tsunami Symposium 2001, Seattle, Washington, Aug. 7 -10, 2001, 569- 577. Richter C. F. (1958), Elementary Seismology, W. H, Freeman and Co., San Francisco, California, 1958

Yalciner, A. C.; Pelinovsky, E. N.

2004-05-01

186

Integrating Caribbean Seismic and Tsunami Hazard into Public Policy and Action  

Science.gov (United States)

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 processes. For example, earthquake and tsunami exercises are conducted separately, without taking into consideration the compounding effects. Recognizing this deficiency, the UNESCO IOC Intergovernmental Coordination Group for the Tsunami and other Coastal Hazards Warning System for the Caribbean and Adjacent Regions (CARIBE EWS) which was established in 2005, decided to include the tsunami and earthquake impacts for the upcoming March 20, 2013 regional CARIBE WAVE/LANTEX tsunami exercise. In addition to the tsunami wave heights predicted by the National Weather Service Tsunami Warning Centers in Alaska and Hawaii, the USGS PAGER and SHAKE MAP results for the M8.5 scenario earthquake in the southern Caribbean were also integrated into the manual. Additionally, in recent catastrophic planning for Puerto Rico, FEMA did request the local researchers to determine both the earthquake and tsunami impacts for the same source. In the US, despite that the lead for earthquakes and tsunamis lies within two different agencies, USGS and NOAA/NWS, it has been very beneficial that the National Tsunami Hazard Mitigation Program partnership includes both agencies. By working together, the seismic and tsunami communities can achieve an even better understanding of the hazards, but also foster more actions on behalf of government officials and the populations at risk.

von Hillebrandt-Andrade, C.

2012-12-01

187

Generating tsunami risk knowledge at community level as a base for planning and implementation of risk reduction strategies  

Directory of Open Access Journals (Sweden)

Full Text Available More than 4 million Indonesians live in tsunami-prone areas along the southern and western coasts of Sumatra, Java and Bali. Although a Tsunami Early Warning Center in Jakarta now exists, installed after the devastating 2004 tsunami, it is essential to develop tsunami risk knowledge within the exposed communities as a basis for tsunami disaster management. These communities need to implement risk reduction strategies to mitigate potential consequences.

The major aims of this paper are to present a risk assessment methodology which (1 identifies areas of high tsunami risk in terms of potential loss of life, (2 bridges the gaps between research and practical application, and (3 can be implemented at community level. High risk areas have a great need for action to improve people's response capabilities towards a disaster, thus reducing the risk. The methodology developed here is based on a GIS approach and combines hazard probability, hazard intensity, population density and people's response capability to assess the risk.

Within the framework of the GITEWS (German-Indonesian Tsunami Early Warning System project, the methodology was applied to three pilot areas, one of which is southern Bali. Bali's tourism is concentrated for a great part in the communities of Kuta, Legian and Seminyak. Here alone, about 20 000 people live in high and very high tsunami risk areas. The development of risk reduction strategies is therefore of significant interest. A risk map produced for the study area in Bali can be used for local planning activities and the development of risk reduction strategies.

S. Wegscheider

2011-02-01

188

The chronology of prehistoric high-energy wave events (tropical cyclones, tsunamis) in the southern Caribbean and their impact on coastal geo-ecosystems – a case study from Bonaire (Leeward Antilles)  

Digital Repository Infrastructure Vision for European Research (DRIVER)

By using sediment archives along the coast of Bonaire (Leeward Antilles; political status: special municipality of the Netherlands), such as bokas (enclosed lagoons), narrow floodplains and mangrove swamps, and by investigating supralittoral blocks and boulders, the goal of this thesis is (i) to identify prehistoric high-energy wave events, (ii) to differentiate between extraordinary storms and tsunamis, and (iii) to date these events. Furthermore, the spatio-temporal impact of high-energy wa...

2012-01-01

189

SEDIMENT CHARACTERISTICS OF THE M-9 TSUNAMI EVENT BETWEEN RAMESWARAM AND THOOTHUKUDI, GULF OF MANNAR, SOUTHEAST COAST OF INDIA  

Directory of Open Access Journals (Sweden)

Full Text Available On 26th December, 2004, a massive earthquake occurred NW of Sumatra in the seismically active zone close to Sunda Trench at a water depth of about 1300m and with an epicenter located at a shallow depth of 10km below the ocean floor. This earthquake triggered tsunami waves in the Indian Ocean and hit most of the Tamilnadu coast, with wave height varying from 3 to 10m. In the study area dunes were breached. Erosional channels were created. Inundation in the study area ranges between 10 and 600m from the shoreline. The inundated sediment thickness varies from 1 to 30cm and was well preserved. Sediments thickness gets reduced landwards and occurs as set of layers. The sediments were fresh, grey to dark grey in color.

S.R.Singarasubramanian

2006-01-01

190

Concept study of radar sensors for near-field tsunami early warning  

Digital Repository Infrastructure Vision for European Research (DRIVER)

Off-shore detection of tsunami waves is a critical component of an effective tsunami early warning system (TEWS). Even more critical is the off-shore detection of local tsunamis, namely tsunamis that strike coastal areas within minutes after generation. In this paper we propose new concepts for near-field tsunami early detection, based on innovative and up-to-date microwave remote sensing techniques. We particularly introduce the NESTRAD (NEar-Space Tsunami RADar) concept, which consists of a...

Bo?rner, T.; Galletti, M.; Marquart, N. P.; Krieger, G.

2010-01-01

191

Concept study of radar sensors for near-field tsunami early warning  

Digital Repository Infrastructure Vision for European Research (DRIVER)

Off-shore detection of tsunami waves is a critical component of an effective tsunami early warning system (TEWS). Even more critical is the off-shore detection of local tsunamis, namely tsunamis that strike coastal areas within minutes after generation. In this paper we propose new concepts for near-field tsunami early detection, based on innovative and up-to-date microwave remote sensing techniques. We particularly introduce the NESTRAD (NEar-Space Tsunami RADar) concept, w...

Bo?rner, T.; Galletti, M.; Marquart, Np; Krieger, G.

2010-01-01

192

Tsunami Risk Management in Pacific Island Countries and Territories (PICTs): Some Issues, Challenges and Ways Forward  

Science.gov (United States)

The Pacific is well known for producing tsunamis, and events such as the 2011 T?hoku-oki, Japan disaster demonstrate the vulnerability of coastal communities. We review what is known about the current state of tsunami risk management for Pacific Island countries and territories (PICTs), identify the issues and challenges associated with affecting meaningful tsunami disaster risk reduction (DRR) efforts and outline strategies and possible ways forward. Small island states are scattered across the vast Pacific region and these states have to varying degrees been affected by not only large tsunamis originating in circum-Pacific subduction zones, but also more regionally devastating events. Having outlined and described what is meant by the risk management process, the various problems associated with our current understanding of this process are examined. The poorly understood hazard related to local, regional and distant sources is investigated and the dominant focus on seismic events at the expense of other tsunami source types is noted. We reflect on the challenges of undertaking numerical modelling from generation to inundation and specifically detail the problems as they relate to PICTs. This is followed by an exploration of the challenges associated with mapping exposure and estimating vulnerability in low-lying coastal areas. The latter part of the paper is devoted to exploring what mitigation of the tsunami risk can look like and draw upon good practice cases as exemplars of the actions that can be taken from the local to regional level. Importantly, given the diversity of PICTs, no one approach will suit all places. The paper closes by making a series of recommendations to assist PICTs and the wider tsunami research community in thinking through improvements to their tsunami risk management processes and the research that can underpin these efforts.

Dominey-Howes, Dale; Goff, James

2013-09-01

193

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

Directory of Open Access Journals (Sweden)

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. The post-event calculations indicated medium-high humanitarian impacts.

E. Ulutas

2012-06-01

194

Historical tsunami database for France and its overseas territories  

Digital Repository Infrastructure Vision for European Research (DRIVER)

A search and analysis of a large number of historical documents has made it possible: (i) to discover so-far unknown tsunamis that have hit the French coasts during the last centuries, and (ii) conversely, to disprove the tsunami nature of several events referred to in recent catalogues. This information has been structured into a database and also made available as a website (tsunamis.f/" target="_blank">http://www.tsunamis.fr) that is acces...

2011-01-01

195

MODELING THE 1958 LITUYA BAY MEGA-TSUNAMI, II  

Directory of Open Access Journals (Sweden)

Full Text Available Lituya Bay, Alaska is a T-Shaped bay, 7 miles long and up to 2 miles wide. The two arms at the head of the bay, Gilbert and Crillon Inlets, are part of a trench along the Fairweather Fault. On July 8, 1958, an 7.5 Magnitude earthquake occurred along the Fairweather fault with an epicenter near Lituya Bay.A mega-tsunami wave was generated that washed out trees to a maximum altitude of 520 meters at the entrance of Gilbert Inlet. Much of the rest of the shoreline of the Bay was denuded by the tsunami from 30 to 200 meters altitude.In the previous study it was determined that if the 520 meter high run-up was 50 to 100 meters thick, the observed inundation in the rest of Lituya Bay could be numerically reproduced. It was also concluded that further studies would require full Navier-Stokes modeling similar to those required for asteroid generated tsunami waves.During the Summer of 2000, Hermann Fritz conducted experiments that reproduced the Lituya Bay 1958 event. The laboratory experiments indicated that the 1958 Lituya Bay 524 meter run-up on the spur ridge of Gilbert Inlet could be caused by a landslide impact.The Lituya Bay impact landslide generated tsunami was modeled with the full Navier- Stokes AMR Eulerian compressible hydrodynamic code called SAGE with includes the effect of gravity.

Charles L. Mader

2002-01-01

196

Selection and Design of a Bore Generator for the Hilo Harbor Tsunami Model: Hydraulic Model Investigation.  

Science.gov (United States)

Theoretical and experimental investigations were made of the generation of a bore by the three following types of bore generator: (a) piston type, (b) gate type, and (c) pneumatic type. The analyses were based on nonlinear shallow-water theory incorporate...

C. C. Shen

1965-01-01

197

The STAR "plug and play" event generator framework  

Science.gov (United States)

The STAR experiment pursues a broad range of physics topics in pp,pA and AA collisions produced by the Relativistic Heavy Ion Collider (RHIC). Such a diverse experimental program demands a simulation framework capable of supporting an equally diverse set of event generators, and a flexible event record capable of storing the (common) particle-wise and (varied) event-wise information provided by the external generators. With planning underway for the next round of upgrades to exploit ep and eA collisions from the electron-ion collider (or eRHIC), these demands on the simulation infrastructure will only increase and requires a versatile framework. STAR has developed a new event-generator framework based on the best practices in the community (a survey of existing approach had been made and the "best of all worlds" kept in mind in our design). It provides a common set of base classes which establish the interface between event generators and the simulation and handles most of the bookkeeping associated with a simulation run. This streamlines the process of integrating and configuring an event generator within our software chain. Developers implement two classes: the interface for their event generator, and their event record. They only need to loop over all particles in their event and push them out into the event record. The framework is responsible for vertex assignment, stacking the particles out for simulation, and event persistency. Events from multiple generators can be merged together seamlessly, with an event record which is capable of tracing each particle back to its parent generator. We present our work and approach in detail and illustrate its usefulness by providing examples of event generators implemented within the STAR framework covering for very diverse physics topics. We will also discuss support for event filtering, allowing users to prune the event record of particles which are outside of our acceptance, and/or abort events prior to the more computationally expensive digitization and reconstruction phases. Event filtering has been supported in the previous framework and showed to save enormous amount of resources – the approach within the new framework is a generalization of filtering.

Webb, J.; Novak, J.; Lauret, J.; Perevoztchikov, V.

2014-06-01

198

Early Detection of Tsunami Scales using GPS  

Science.gov (United States)

This talk reviews how tsunamis form from earthquakes and how GPS technologies can be used to detect tsunami energy scales in real time. Most tsunami fatalities occur in near-field communities of earthquakes at offshore faults. Tsunami early warning is key for reducing the number of fatalities. Unfortunately, an earthquake's magnitude often does not gauge the resulting tsunami power. Here we show that real-time GPS stations along coastlines are able to detect seafloor motions due to big earthquakes, and that the detected seafloor displacements are able to determine tsunami energy and scales instantaneously for early warnings. Our method focuses on estimating tsunami energy directly from seafloor motions because a tsunami's potential or scale, no matter how it is defined, has to be proportional to the tsunami energy. Since seafloor motions are the only source of a tsunami, their estimation directly relates to the mechanism that generates tsunamis; therefore, it is a proper way of identifying earthquakes that are capable of triggering tsunamis, while being able to discriminate those particular earthquakes from false alarms. Examples of detecting the tsunami energy scales for the 2004 Sumatra M9.1 earthquake, the 2005 Nias M8.7 earthquake, the 2010 M8.8 Chilean earthquake, and the 2011 M9.0 Tohoku-Oki earthquake will be presented. Related reference: 1. Xu, Z. and Y. T. Song (2013), Combining the all-source Green's functions and the GPS-derived source for fast tsunami prediction - illustrated by the March 2011 Japan tsunami, J. Atmos. Oceanic Tech., jtechD1200201. 2. Song, Y. T., I. Fukumori, C. K. Shum, and Y. Yi (2012), Merging tsunamis of the 2011 Tohoku-Oki earthquake detected over the open ocean, Geophys. Res. Lett., doi:10.1029/2011GL050767. 3. Song, Y. T. and S.C. Han (2011) Satellite observations defying the long-held tsunami genesis theory, D.L. Tang (ed.), Remote Sensing of the Changing Oceans, DOI 10.1007/978-3-642-16541-2, Springer-Verlag Berlin Heidelberg. 4. Song, Y. T. (2007) Detecting tsunami genesis and scales directly from coastal GPS stations, Geophys. Res. Lett., 34, L19602, doi:10.1029/2007GL031681.

Song, Y.

2013-12-01

199

Pliocene mass failure deposits mistaken as submarine tsunami backwash sediments - An example from Hornitos, northern Chile  

Science.gov (United States)

In this study we question the former interpretation of a shallow marine backwash tsunami origin of a conspicuous Pliocene coarse clastic unit at Hornitos, northern Chile, and instead argue for a debris flow origin for this unit. We exclude a relation to a tsunami in general and to the Eltanin impact in particular. The observed deposit at Hornitos was not generated either directly (impact-triggered tsunami) or indirectly (submarine mass flow caused by seismic shaking) by an impact. Re-calculation of the alleged impact tsunami including consideration of the Van Dorn effect shows that an impact in the Southern Ocean did not cause a significant tsunami at Hornitos. Impact-related seismic shaking was not able to trigger slides several thousands of kilometers away because the Eltanin event was a deep sea-impact that did not create a crater. Additionally, the biostratigraphic age of 5.1-2.8 Ma of the associated La Portada Formation is not concurrent with the newly established age of 2.511 ± 0.07 Ma for the Eltanin impact. Instead, we argue for an origin of the conspicuous unit at Hornitos as a debris flow deposit caused by an earthquake in the Andean subduction zone in northern Chile. Our re-interpretation considers the local synsedimentary tectonic background, a comparison to recent submarine tsunami sediments, and recent examples of mass wasting deposits along the Chilean margin. The increased uplift during the Pliocene caused oversteepening of the coastal scarp and entailed a contemporaneous higher frequency of seismic events that triggered slope failures and cliff collapses. The coarse clastic unit at Hornitos represents an extraordinary, potentially tsunami-generating mass wasting event that is intercalated with mass wasting deposits on a smaller scale.

Spiske, Michaela; Bahlburg, Heinrich; Weiss, Robert

2014-05-01

200

TSUNAMI CATALOG AND VULNERABILITY OF MARTINIQUE (LESSER ANTILLES, FRANCE)  

Digital Repository Infrastructure Vision for European Research (DRIVER)

In addition to meteorological hazards (hurricanes, heavy rainfalls, long-period swells, etc.), the Caribbean Islands are vulnerable to geological hazards such as earthquakes, landslides and volcanic eruptions caused by the complex tectonic activity and interactions in the region. Such events have generated frequently local or regional tsunamis, which often have affected the island of Martinique in the French West Indies. Over the past centuries, the island has been struck by destructive waves...

2010-01-01

 
 
 
 
201

Response of Coastal Structures against Earthquake Forces Considering Soil-Structure Interaction and Tsunami Run-Up Forces  

Directory of Open Access Journals (Sweden)

Full Text Available The catastrophic tsunamis generated by the great Indonesia earthquake triggered on December 26th, 2004, warned the coastal community on preparedness and constructing safe structures to resist against such events. Earthquake occurs suddenly without warning and bulk of destruction takes place within a short period of time. Similarly, when tsunami strikes, there will be a tremendous loss and damage in coastal regions. Apart from having a sound warning system in case of tsunamis, it is necessary to build Earthquake–Tsunami Resistant (ETR shelters, where residents living in coastal plain regions cannot move to farther distances before tsunami arrives the coast. Hence it is necessary to establish analytical methods for obtaining the response of coastal structures subjected to earthquake forces considering soil-structure interaction and also against tsunami run-up forces. A three storied shelter building with four different cases of structural configurations and another typical structure, an elevated water tank of 6 lakh liters capacity are chosen for the analysis. A comparative study is made on the response of these structures against earthquake forces, when they rest on different soil/rock media. In the analysis, IS 1893-2002 seismic code for determining the base shear values against earthquake loads and FEMA 55 to calculate hydrodynamic and impact forces against tsunami impact are used. From the results, it is observed that the refuge shelters that are chosen are more vulnerable to high tide tsunami loads compared to earthquake loads. In general, it is noticed that Base shears and Displacements increase with the decreases in stiffness of the soil and this increase attributes more due to rocking effect of the soil. Buildings with open storey at bottom and upper stories with heavy mass give significant rise to time period of these structures causing early failures during an earthquake before tsunami arrives. In this study, a useful guideline is evaluated demarcating the heights below which earthquake forces and above which tsunami forces are predominant in the structure.

Prof.P.Kodanda Ramarao,

2013-06-01

202

Generation of surface waves by an underwater moving bottom: Experiments and application to tsunami modelling  

Digital Repository Infrastructure Vision for European Research (DRIVER)

We report laboratory experiments on surface waves generated in a uniform fluid layer whose bottom undergoes a sudden upward motion. Simultaneous measurements of the free-surface deformation and the fluid velocity field are focused on the role of the bottom kinematics in wave generation. We observe that the fluid layer transfers bottom motion to the free surface as a temporal high-pass filter coupled with a spatial low-pass filter. Both filter effects are usually neglected in...

Jamin, Timothe?e; Gordillo, Leonardo; Ruiz-chavarri?a, Gerardo; Berhanu, Michael; Falcon, Eric

2014-01-01

203

A Monte Carlo Approach for Estimating Tsunami Hazard from Submarine Mass Failure Along the U.S. East Coast  

Science.gov (United States)

This work is being conducted as part of the development of tsunami inundation maps for the U.S. East Coast (USEC), as mandated by the National Tsunami Hazard Mitigation Program (NTHMP). Along the USEC, which borders the Atlantic Ocean Basin, tsunami hazard may result from large distant co-seismic sources (e.g., in the Puerto Rico Trench or the Azores convergence zone) or volcanic flank collapse sources (e.g., in the Canary Islands). More importantly, however, tsunami hazard may result from Submarine Mass Failures (SMFs) occurring along the nearby continental shelf break and slope (e.g., 1929 Grand Bank). Indeed, potentially large tsunamigenic SMFs can be triggered by moderate seismic activity, such as could occur along the USEC, and cause large local tsunamis. While many past SMFs have been identified along the USEC and described in various publications (e.g., by USGS), due to the paucity of historical tsunami observations in this area, the associated tsunami hazard and its recurrence probability are largely unknown. To estimate the latter, in earlier work, we developed, validated with field data, and applied a Monte Carlo simulation (MCS) approach (Grilli et al., Marine Geology, vol. 264, p74, 2009) to the upper USEC (north of New Jersey). Here, a similar methodology is applied to the entire USEC. In the present MCSs, distributions of relevant parameters (e.g., seismicity, sediment properties, type and location, volume, and dimensions of slide, water depth) are used to perform large numbers (O(105)) of stochastic stability analyses of submerged slopes (along actual shelf transects), based on standard pseudo-static limit equilibrium methods. The predicted SMF types (i.e., translational or rotational), surface area, and slope angle are found to match published field data quite well along the USEC. For each parameter configuration found to be unstable under a specified ground acceleration (of given return period), the tsunami source characteristic height, and corresponding runup distribution on nearby shores, are calculated using empirical equations based on earlier numerical simulation work. A final statistical analysis of generated runup values yields estimates of overall coastal hazard, from 100 and 500-yr SMF tsunami events. The latter allows identifying regions of the USEC with elevated hazard (and related SMF parameters), where complete and detailed SMF tsunami simulations should be performed. The latter will be the object of the continuation of this NTHMP work, in which inundation from SMF tsunamis thus identified will be combined with that from other tsunami sources, to develop a series of tsunami inundation maps for areas of elevated tsunami hazard along the USEC.

Baxter, C. D.; Krause, T.; Grilli, S. T.

2011-12-01

204

THE TSUNAMI HISTORY OF GUAM: 1849-1993  

Directory of Open Access Journals (Sweden)

Full Text Available The great (Mw 8.1 tsunamigenic earthquake of August 8, 1993, about 50 km to the east of Guam, has created renewed interest in the tsunami hazard for the island of Guam. We examine this hazard from two perspectives--historical and mechanistic. Guam has had only three tsunamis causing damage at more than one location--in 1849, 1892, and in 1993, and only two to six other locally-generated tsunamis which were observed on the island in the past 200 years. Five of these six events have low validities and may not be reports of true tsunami. On the other hand, dozens of storm surges related to typhoons have caused millions of dollars of damage on Guam. The island of Guam is located west of the Marianas Trench. The trench is caused by the subduction of old, cold, and dense lithosphere of the Pacific plate under the Philippine plate. Steeply dipping old material is unlikely to trigger tsunamis because (1 the two plates are decoupled and (2 the motion is too slow to allow large amounts of stress to build up before earthquakes occur, resulting in less violent earthquakes. A small section of the Marianas Trench near Guam, however, has shallow subduction. This is where the 1993 event occurred, and a quiet area south of this may be the site of a similar future tsunamigenic earthquake. Most of the damage from a local tsunami would occur on the relatively unpopulated east coast; the likelihood of a local tsunami from the west is minimal. However, a repeat of the 1848 tsunami with a southern source could affect both the east and west coasts. The 1993 earthquake occurred coincident with the passage of Typhoon Steve. We show that this may not be coincidental as there is a substantial statistical correlation between earthquakes and typhoons at Guam. The close encounter of a typhoon with Guam doubles the probability of an earthquake with magnitude greater than 5.0 occurring on that day.

James F. Lander

2002-01-01

205

PROFESSOR: Systematic tuning of Monte Carlo event generators  

International Nuclear Information System (INIS)

The non-perturbative part of an event in a Monte Carlo event generator is described by certain models that are approximations to the actually happening physics processes. These models comprise a large number of partly strongly correlated and relatively free parameters. In addition, the machinery of attaching perturbative and non-perturbative regimes together is steered by parameters that have no physical meaning. The quality of the model description can be tested by comparing experimental data with the observables derived from the generated events. So far, the tuning of Monte Carlo event generators was attempted by means of trial and error or enormous computing time. In this talk the software PROFESSOR (PROcedure For Estimating SyStematic errORs) is presented which represents a systematic approach to find optimal parameter values by fitting a parameterisation of the generator's description of observables to high-precision data. Examples of the application to models of fragmentation and the underlying event are being presented

2009-03-09

206

The 1945 Balochistan earthquake and probabilistic tsunami hazard assessment for the Makran subduction zone  

Science.gov (United States)

Iran and Pakistan are countries quite frequently affected by destructive earthquakes. For instance, the magnitude 6.6 Bam earthquake in 2003 in Iran with about 30'000 casualties, or the magnitude 7.6 Kashmir earthquake 2005 in Pakistan with about 80'000 casualties. Both events took place inland, but in terms of magnitude, even significantly larger events can be expected to happen offshore, at the Makran subduction zone. This small subduction zone is seismically rather quiescent, but a tsunami caused by a thrust event in 1945 (Balochistan earthquake) led to about 4000 casualties. Nowadays, the coastal regions are more densely populated and vulnerable to similar events. Additionally, some recent publications raise the question of the possiblity of rare but huge magnitude 9 events at the Makran subduction zone. We first model the historic Balochistan event and its effect in terms of coastal wave heights, and then generate various synthetic earthquake and tsunami catalogs including the possibility of large events in order to asses the tsunami hazard at the affected coastal regions. Finally, we show how an effective tsunami early warning could be achieved by the use of an array of high-precision real-time GNSS (Global Navigation Satellite System) receivers along the coast.

Höchner, Andreas; Babeyko, Andrey; Zamora, Natalia

2014-05-01

207

Tsunami diaries  

Digital Repository Infrastructure Vision for European Research (DRIVER)

Inspired by recent discussion on how Serbian media influenced allegedly indifferent reaction of the public to the aftermath of tsunami, this paper examines the role of electronic media in Serbia, television in particular, in regard to their function as a central communication channel for acquiring knowledge about world surroundings. With a premise of having cultural and discursive power, Dnevnik, the central news program of the Serbian public broadcaster, is taken as a paradigmatic media text...

Radovi? Sr?an

2005-01-01

208

ALGERIA’S VULNERABILITY TO TSUNAMIS FROM NEAR-FIELD SEISMIC SOURCES  

Digital Repository Infrastructure Vision for European Research (DRIVER)

Evaluation of the effects of tsunami damage relative to earthquake damage may help to identify critical coastal zone structures and exposed populations for near field tsunami risk. In this work, we propose to define the ratio between tsunami intensity and earthquake intensity as a measure of near field tsunami vulnerability for coastal communities. This parameter is estimated for 13 tsunami events reported in North Algeria from the 14th century to present. Although the results show that there...

2012-01-01

209

Simulation of space-borne tsunami detection using GNSS-Reflectometry applied to tsunamis in the Indian Ocean  

Directory of Open Access Journals (Sweden)

Full Text Available Within the German-Indonesian Tsunami Early Warning System project GITEWS (Rudloff et al., 2009, a feasibility study on a future tsunami detection system from space has been carried out. The Global Navigation Satellite System Reflectometry (GNSS-R is an innovative way of using reflected GNSS signals for remote sensing, e.g. sea surface altimetry. In contrast to conventional satellite radar altimetry, multiple height measurements within a wide field of view can be made simultaneously. With a dedicated Low Earth Orbit (LEO constellation of satellites equipped with GNSS-R, densely spaced sea surface height measurements could be established to detect tsunamis. This simulation study compares the Walker and the meshed comb constellation with respect to their global reflection point distribution. The detection performance of various LEO constellation scenarios with GPS, GLONASS and Galileo as signal sources is investigated. The study concentrates on the detection performance for six historic tsunami events in the Indian Ocean generated by earthquakes of different magnitudes, as well as on different constellation types and orbit parameters. The GNSS-R carrier phase is compared with the PARIS or code altimetry approach. The study shows that Walker constellations have a much better reflection point distribution compared to the meshed comb constellation. Considering simulation assumptions and assuming technical feasibility it can be demonstrated that strong tsunamis with magnitudes (M ?8.5 can be detected with certainty from any orbit altitude within 15–25 min by a 48/8 or 81/9 Walker constellation if tsunami waves of 20 cm or higher can be detected by space-borne GNSS-R. The carrier phase approach outperforms the PARIS altimetry approach especially at low orbit altitudes and for a low number of LEO satellites.

R. Stosius

2010-06-01

210

Tsunami magnetic signals in the Northwestern Pacific seafloor magnetic measurements  

Science.gov (United States)

In the past two decades, underwater cables and seafloor magnetometers have observed motional inductance from ocean tsunamis. This study aimed to characterize the electromagnetic signatures of tsunamis from seafloor stations to assist in the long-term goal of real-time tsunami detection and warning systems. Four ocean seafloor stations (T13, T14, T15, T18) in the Northeastern Philippine Sea collected vector measurements of the electric and magnetic fields every minute during the period of 10/05/2005 to 11/30/2007 (Baba et al., 2010 PEPI). During this time, four major tsunamis occurred as a result of moment magnitude 8.0-8.1 earthquakes. These tsunamis include the 05/03/2006 Tonga event, the 01/13/2007 Kuril Islands event, the 04/01/2007 Solomon Islands event, and the 08/15/2007 Peru event. The Cornell Multi-grid Coupled Tsunami model (COMCOT) was used to predict the arrival time of the tsunamis at each of the seafloor stations. The stations' raw magnetic field signals underwent a high pass filter to then be examined for signals of the tsunami arrival. The high pass filtering showed clear tsunami signals for the Tonga event, but a clear signal was not seen for the other events. This may be due to signals from near Earth space with periods similar to tsunamis. To remove extraneous atmospheric magnetic signals, a cross-wavelet analysis was conducted using the horizontal field components from three INTERMAGNET land stations and the vertical component from the seafloor stations. The cross-wavelet analysis showed that for three of the six stations (two of the four tsunami events) the peak in wavelet amplitude matched the arrival of the tsunami. We discuss implications of our finding in magnetic monitoring of tsunamis.

Schnepf, N. R.; An, C.; Nair, M. C.; Maus, S.

2013-12-01

211

EL TERREMOTO Y POSTERIOR TSUNAMI DEL 26 DE DICIEMBRE DE 2004 EN INDONESIA  

Scientific Electronic Library Online (English)

Full Text Available SciELO Colombia | Language: Spanish Abstract in english A short compilation of the cause, characteristics and effects of the tsunami generated on the 26 of December of 2004 in Indonesia is presented here. The general context of generation of this phenomena is illustrated together with the tectonic environment in which this tsunami in particular was produ [...] ced. Finally, a brief introduction to tsunamis in Colombia including tsunami cases and areas of higher tsunami hazard is considered.

ESTRADA ROLDÁN, BEATRIZ ELENA; FARBIARZ FARBIARZ, JOSEF.

212

The open ocean energy decay of three recent trans-Pacific tsunamis  

Science.gov (United States)

The 2009 Samoa (Mw 8.1), 2010 Chile (8.8), and 2011 Tohoku (9.0) earthquakes generated destructive tsunamis recorded by a large number of DART stations in the Pacific Ocean. High-resolution (15 s) DART records yield mean energy decay times for these events of 17.3, 24.7, and 24.6 h, respectively. We attribute these differences to the frequency content of the tsunamis. Specifically, the Samoa tsunami was a "high-frequency" event with periods of 2-30 min whereas the Chile and Tohoku tsunamis were "broad-band" events with periods of 2-180 min. Differences in frequency content are linked to differences in the source parameters: Samoa was a relatively small deep-water earthquake while Chile and Tohoku were extensive shallow-water earthquakes. Frequency-dependent analysis of the Chile and Tohoku tsunamis indicates that shorter period waves attenuate much faster than longer-period waves (decay times range from 15 h for 2-6 min waves to 29 h for 60-180 min waves).

Rabinovich, Alexander B.; Candella, RogéRio N.; Thomson, Richard E.

2013-06-01

213

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)

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 platform must be able to recognise and match during the early crisis management phase. The MSDB contains a very large number (order of thousands) of tsunami simulations performed starting from many different simple earthquake sources of different magnitudes and located in the "vicinity" of the virtual scenario earthquake. Examples from both databases will be presented.

Tinti, S.; Armigliato, A.; Pagnoni, G.; Zaniboni, F.

2012-04-01

214

Simulation and event generation in high-energy physics  

International Nuclear Information System (INIS)

A basic introduction to the physics modeling, the event generation and the detector simulation as designed for the upcoming high-energy physics experiments is presented. Requirements on software developments and computing performances are stressed. (author)

2002-07-01

215

SAFRR Tsunami Scenario. Preparedness and Resilience for California's ecosystems, natural resources, and the communities that depend on them  

Science.gov (United States)

The SAFRR Tsunami Scenario models a plausible 9.1MP earthquake occuring off the Alaskan coast, that generates a tsunami forecast to strike California between 4-6 hour after the event. California's diverse ecosystems, natural resources, and sensitive species will be significantly affected. Although often overlooked in disaster risk reduction, damage to ecosystems and natural resources during hazards including tsunamis, has often resulted in serious impacts to natural systems and on humans who depend on them. SAFRR tsunami scenario forecasts of wave amplitude, water velocity and inundation and overlain on GIS maps were analyzed to identify plausible impacts on California's ecosystems including beaches, marshes, nearshore subtidal habitats, as well as parks and reserves. The effect on natural resources including fisheries was evaluated. Recovery times and consequences were analyzed. The results illustrate the value and vulnerability of these resources and guidelines for preparation and mitigation are discussed.

Brosnan, D. M.

2013-12-01

216

Introduction to "Historical and Recent Catastrophic Tsunamis in the World: Volume II. Tsunamis from 1755 to 2010"  

Science.gov (United States)

Eighteen papers on past and recent destructive tsunamis are included in Volume II of the PAGEOPH topical issue "Historical and Recent Catastrophic Tsunamis in the World." Three papers discuss deep-sea (DART) and coastal tsunami observations, warning systems and risk management in the Pacific Ocean. Four papers examine the 1755 Lisbon, 1964 Alaska, 2003 Algeria, and 2011 Haiti tsunamis. Four more papers, as well as some papers in Volume I, report on various aspects of the 2010 Chile tsunami. Two papers present some results of field survey and modelling investigation of the 2010 Mentawai, Indonesia, tsunami. Three papers report on modelling efforts of tsunami generation by earthquake and landslide, and of tsunami propagation. Finally, two papers discuss hazard assessment using a probabilistic approach.

Satake, Kenji; Rabinovich, Alexander B.; Dominey-Howes, Dale; Borrero, José C.

2013-09-01

217

How to learn and develop from both good and bad lessons- the 2011Tohoku tsunami case -  

Science.gov (United States)

The 2011 Tohoku tsunami revealed Japan has repeated same mistakes in a long tsunami disaster history. After the disaster Japanese remember many old lessons and materials: an oral traditional evacuation method 'Tsunami TENDENKO' which is individual independent quick evacuation, a tsunami historical memorial stone "Don't construct houses below this stone to seaside" in Aneyoshi town Iwate prefecture, Namiwake-shrine naming from the story of protect people from tsunami in Sendai city, and so on. Tohoku area has created various tsunami historical cultures to descendent. Tohoku area had not had a tsunami disaster for 50 years after the 1960 Chilean tsunami. The 2010 Chilean tsunami damaged little fish industry. People gradually lost tsunami disaster awareness. At just the bad time the magnitude (M) 9 scale earthquake attacked Tohoku. It was for our generations an inexperienced scale disaster. People did not make use of the ancestor's lessons to survive. The 2004 Sumatra tsunami attacked just before 7 years ago. The magnitude scale is almost same as M 9 scale. Why didn't Tohoku people and Japanese tsunami experts make use of the lessons? Japanese has a character outside Japan. This lesson shows it is difficult for human being to learn from other countries. As for Three mile island accident case in US, it was same for Japan. To addition to this, there are similar types of living lessons among different hazards. For examples, nuclear power plantations problem occurred both the 2012 Hurricane Sandy in US and the 2011 Tohoku tsunami. Both local people were not informed about the troubles though Oyster creek nuclear power station case in US did not proceed seriously all. Tsunami and Hurricane are different hazard. Each exparts stick to their last. 1. It is difficult for human being to transfer living lessons through next generation over decades. 2. It is difficult for human being to forecast inexperienced events. 3. It is usually underestimated the danger because human being have a tendency to judge based on own experience. 4. It is difficult for human being to make use of lessons from different countries because human being would not like to think own self suffer victim for a self-preservation mind. 5. It is usual for experts not to pay attention to other fields even if similar case occurs in different fields. We started collecting 18 hazards of such historical living lessons all over the world before the 2011 Tohoku tsunami. We adapted to this project collecting lessons from Tohoku tsunami and will publish for small children in developing countries in March 2013. This will be translated in at least 10 languages. This disaster lessons guide books are free. We will introduce some lessons in the presentations. We believe education is one of useful countermeasures to prevent from repeating same mistakes and transfer directly living lessons to new generations.

Sugimoto, Megumi; Okazumi, Toshio

2013-04-01

218

Advanced Planning for Tsunamis in California  

Science.gov (United States)

The California Tsunami Program is comprised of the California Governor's Office of Emergency Services (CalOES) and the California Geological Survey (CGS) and funded through the National Tsunami Hazard Mitigation Program (NTHMP) and the Federal Emergency Management Agency (FEMA). The program works closely with the 20 coastal counties in California, as well as academic, and industry experts to improve tsunami preparedness and mitigation in shoreline communities. Inundation maps depicting 'worst case' inundation modeled from plausible sources around the Pacific were released in 2009 and have provided a foundation for public evacuation and emergency response planning in California. Experience during recent tsunamis impacting the state (Japan 2011, Chile 2010, Samoa 2009) has brought to light the desire by emergency managers and decision makers for even more detailed information ahead of future tsunamis. A solution to provide enhanced information has been development of 'playbooks' to plan for a variety of expected tsunami scenarios. Elevation 'playbook' lines can be useful for partial tsunami evacuations when enough information about forecast amplitude and arrival times is available to coastal communities and there is sufficient time to make more educated decisions about who to evacuate for a given scenario or actual event. NOAA-issued Tsunami Alert Bulletins received in advance of a distant event will contain an expected wave height (a number) for each given section of coast. Provision of four elevation lines for possible inundation enables planning for different evacuation scenarios based on the above number potentially alleviating the need for an 'all or nothing' decision with regard to evacuation. Additionally an analytical tool called FASTER is being developed to integrate storm, tides, modeling errors, and local tsunami run-up potential with the forecasted tsunami amplitudes in real-time when a tsunami Alert is sent out. Both of these products will help communities better implement evacuations and response activities for minor to moderate (less than maximum) tsunami events. A working group comprised of federal, state, and local governmental scientists, emergency managers, first responders, and community planners has explored details and delivery of the above tools for incorporation into emergency management protocols. The eventual outcome will be inclusion in plans, testing of protocols and methods via drills and exercises and application, as appropriate, during an impending tsunami event.

Miller, K.; Wilson, R. I.; Larkin, D.; Reade, S.; Carnathan, D.; Davis, M.; Nicolini, T.; Johnson, L.; Boldt, E.; Tardy, A.

2013-12-01

219

Les Houches Squared Event Generator for the NMSSM  

Energy Technology Data Exchange (ETDEWEB)

We present a generic framework for event generation in the Next-to-Minimal Supersymmetric Standard Model (NMSSM), including the full chain of production process, resonance decays, parton showering, hadronization, and hadron decays. The framework at present uses NMHDECAY to compute the NMSSM spectrum and resonance widths, CALCHEP for the generation of hard scattering processes, and PYTHIA for resonance decays and fragmentation. The interface between the codes is organized by means of two Les Houches Accords, one for supersymmetric mass and coupling spectra (SLHA,2003) and the other for the event generator interface (2000).

Pukhov, A.; /Moscow State U.; Skands, P.; /Fermilab

2005-12-01

220

Les Houches Squared Event Generator for the NMSSM  

International Nuclear Information System (INIS)

We present a generic framework for event generation in the Next-to-Minimal Supersymmetric Standard Model (NMSSM), including the full chain of production process, resonance decays, parton showering, hadronization, and hadron decays. The framework at present uses NMHDECAY to compute the NMSSM spectrum and resonance widths, CALCHEP for the generation of hard scattering processes, and PYTHIA for resonance decays and fragmentation. The interface between the codes is organized by means of two Les Houches Accords, one for supersymmetric mass and coupling spectra (SLHA,2003) and the other for the event generator interface (2000)

2005-01-01

 
 
 
 
221

Washington Tsunami Hazard Mitigation Program  

Science.gov (United States)

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.

Walsh, T. J.; Schelling, J.

2012-12-01

222

Concerning the Perturbations Generated by Flux Transfer Events  

Science.gov (United States)

The interaction of the solar wind with the Earth's magnetosphere is often highly unsteady. Bursts of magnetic reconnection at multiple locations on the dayside equatorial magnetopause generate flux transfer events or FTEs: twisted ropes of interconnected magnetosheath and magnetospheric magnetic field lines. Once formed, the events move antisunward, displacing and perturbing the ambient media. This talk explores the perturbations predicted by both global numerical simulations and analytical models. Results from global hybrid code simulation confirm the predictions of analytical models indicating that the events generate standing forward slow mode waves as their speeds relative to the magnetosheath flow approach the Alfven velocity. Geometric considerations lead to the conclusion that events generated by component reconnection on the dayside magnetopause move poleward and exhibit strong signatures during intervals of southward IMF orientation, but move towards the flanks and exhibit weak signatures during intervals of northward IMF orientation. Changing event orientations and magnetosheath/magnetospheric magnetic field orientation can enhance the amplitudes of events reaching the flanks. Although the orientations of events on the flanks inferred from multispacecraft timing techniques are consistent with the predictions of the component reconnection model, occurrence patterns versus latitude and IMF orientation require an explanation in terms of both the component and antiparallel reconnection models.

Sibeck, David G.

2010-01-01

223

Event generator mode introduced in the PHITS code  

International Nuclear Information System (INIS)

Particle and Heavy Ion Transport code System (PHITS) for general purposes has been used in different fields related to accelerators, space aeronautics, and medical applications including particle beam cancer therapy. Event Generator Mode which was recently added to this code expanded the application field further by making it possible to analyze intensity distribution which is important to investigate radiation behavior in microscopic scales. This is the first attempt in the world to study the radiation effects based from the microscopic viewpoint, and is expected to build bridges to the microdosimetry of materials, life science and so on. In this report, the general concept of event generator is explained following a brief introduction of PHITS. Then the event generator model is introduced and its verification is shown by comparing cross sections of photons and charged particles calculated by using the event generator model with experimental ones available. Finally an application of the event generator mode to boron neutron capture therapy (BNCT) is presented illustrating the ?m-scale radiation effect figures which show different distribution of tracks of Li and ? within the cell according to different position of boron carrier adhesion. (S. Funahashi)

2008-05-01

224

The Hawaiian Islands - Integrated Approach to Understanding the Tsunami Risk in the Pacific (Invited)  

Science.gov (United States)

The Hawaiian Islands, because of their location in the middle of the Pacific Ocean, act as natural ';barometers' for tsunamis generated along the Pacific Ring of Fire, which is the most seismically active area in the world. A multi-proxy study in the remote Pololu valley on the Big Island provided the first evidence for two trans-Pacific events, namely the 1946 and 1957 Aleutian tsunamis. These were identified using radiometric, stratigraphic, microfossil, pollen and geochemical proxies and were corroborated by historical accounts. The islands have been impacted repeatedly by tsunamis in historical times (inc. the recent 2010 Maule and 2011 Tohoku-oki events), and there is strong archaeological evidence for large events affecting humans in prehistory. However, no geological research has yet been carried out, except for some associated with a palaeoecological study on Kauai. Historical evidence shows that tsunamis emanating from the Pacific Ring of Fire have run up to different elevations on different islands within the island chain depending upon their source. Here there is a possible key to understanding some of the key questions about the magnitude and frequency of tsunamis from various parts of the Pacific. Tsunamis from Japan are large on the SW side of the Big Island, those from Alaska seem to have been large in the NE of the island and so on throughout the island chain. A careful site selection from throughout the islands offers a unique opportunity to chart the palaeotsunami record of the Hawaiian Islands while at the same time matching and enhancing the palaeoseismic record of sources in the Pacific Ring of Fire. How big and how often events have occurred in circum-Pacific locations, and how badly they affected other Pacific nations may therefore be addressed by looking in the middle of the Pacific Ocean.

Chague-Goff, C.

2013-12-01

225

Tsunamis: Detecting, Simulating, and Chasing Them  

Energy Technology Data Exchange (ETDEWEB)

Tsunamis are gravitational oscillations of the water mass of an ocean basin set up by earthquakes, landslides, volcanic eruptions, or bolide impacts. They represent an exceptional hazard capable of inflicting death and destruction on a global scale. Because their waves travel at a relatively slow speed (typically 200 m/s or the speed of a jetliner), there exists an opportunity for warning, at least in the far field. We will review the basic physics of the tsunami wave, the relationship between seismic source and tsunami excitation, and the scientific bases underlying the mitigation, warning, computer simulation, and real time detection of tsunami waves. In particular, we will describe the development of robust discriminants in the near and far fields for tsunamis generated by earthquakes and landslides, and will give examples of field methods for the recovery of quantitative databases of inundation measurements.

Okal, Emile A. (Northwestern University)

2005-02-23

226

Evaluation of tsunami vulnerability along northeast coast of India  

Science.gov (United States)

The Sumatra tsunami of 26 December 2004 with a moment magnitude of 9.3 Mw caused colossal damage to the south-southeastern Indian coast and Andaman-Nicobar group of Islands. However, the northeastern coastline bordering the northwestern Bay of Bengal remained unaffected although a tidal station located in the region recorded the highest water level (~2.5 m) for the entire east coast of India on the eventful day. As a part of hazard mitigation and planning for the northeastern coast, four major settlements, viz., Gopalpur, Puri, Paradip and Digha were evaluated for tsunami vulnerability. Inundation and run-up scenarios were generated for Bay of Bengal earthquake sources such as Arakan-1762, Car Nicobar-1881, North Andaman-1941 and Sumatra 2004 using TUNAMI N2 model. The paper describes computed run-up heights and landward inundation for 20-25 km coastal stretch with different geomorphologies and topographical characteristics. Simulation results indicate that the model is able to generate a comparable run-up of 2-4.5 m for 2004 Sumatra event for Paradip region while at other locations of the coastline, it was largely unnoticed as the inundation remained within the beach limit; however water entered inland mainly through the waterways and inundated low-lying areas. It is concluded that northeast coast of India is relatively safe from the tsunami originating in Bay of Bengal region.

Mishra, Pravakar; Usha, Tune; Ramanamurthy, M. V.

2014-05-01

227

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)

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.

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

2014-01-01

228

Tsunami Forecast by Joint Inversion of Real-Time Tsunami Waveforms and Seismic or GPS Data: Application to the Tohoku 2011 Tsunami  

Science.gov (United States)

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.

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

2014-04-01

229

Overview of the BlockNormal Event Trigger Generator  

CERN Document Server

In the search for unmodeled gravitational wave bursts, there are a variety of methods that have been proposed to generate candidate events from time series data. Block Normal is a method of identifying candidate events by searching for places in the data stream where the characteristic statistics of the data change. These change-points divide the data into blocks in which the characteristics of the block are stationary. Blocks in which these characteristics are inconsistent with the long term characteristic statistics are marked as Event-Triggers which can then be investigated by a more computationally demanding multi-detector analysis.

McNabb, J W C; Finn, L S; Rotthoff, E; Stuver, A; Summerscales, T; Sutton, P; Tibbits, M; Thorne, K; Zaleski, K D

2004-01-01

230

How volcanic eruptions cause tsunamis  

Science.gov (United States)

This study investigates the effect of pyroclastic flows on tsunami generation. The authors analyzed several possible mechanisms that occur when the particle rich flows encounter water and conclude that the volume and density of the basal flow has a close correlation with the wave's amplitude and wavelength, which can be used to model the water movement in lakes, bays and oceans.

Watts, Phil; Waythomas, C. F.; Agu

231

General-purpose event generators for LHC physics  

Science.gov (United States)

We review the physics basis, main features and use of general-purpose Monte Carlo event generators for the simulation of proton-proton collisions at the Large Hadron Collider. Topics included are: the generation of hard scattering matrix elements for processes of interest, at both leading and next-to-leading QCD perturbative order; their matching to approximate treatments of higher orders based on the showering approximation; the parton and dipole shower formulations; parton distribution functions for event generators; non-perturbative aspects such as soft QCD collisions, the underlying event and diffractive processes; the string and cluster models for hadron formation; the treatment of hadron and tau decays; the inclusion of QED radiation and beyond Standard Model processes. We describe the principal features of the ARIADNE, Herwig++, PYTHIA 8 and SHERPA generators, together with the Rivet and Professor validation and tuning tools, and discuss the physics philosophy behind the proper use of these generators and tools. This review is aimed at phenomenologists wishing to understand better how parton-level predictions are translated into hadron-level events as well as experimentalists seeking a deeper insight into the tools available for signal and background simulation at the LHC.

Buckley, Andy; Butterworth, Jonathan; Gieseke, Stefan; Grellscheid, David; Höche, Stefan; Hoeth, Hendrik; Krauss, Frank; Lönnblad, Leif; Nurse, Emily; Richardson, Peter; Schumann, Steffen; Seymour, Michael H.; Sjöstrand, Torbjörn; Skands, Peter; Webber, Bryan

2011-07-01

232

General-purpose event generators for LHC physics  

Energy Technology Data Exchange (ETDEWEB)

We review the physics basis, main features and use of general-purpose Monte Carlo event generators for the simulation of proton-proton collisions at the Large Hadron Collider. Topics included are: the generation of hard-scattering matrix elements for processes of interest, at both leading and next-to-leading QCD perturbative order; their matching to approximate treatments of higher orders based on the showering approximation; the parton and dipole shower formulations; parton distribution functions for event generators; non-perturbative aspects such as soft QCD collisions, the underlying event and diffractive processes; the string and cluster models for hadron formation; the treatment of hadron and tau decays; the inclusion of QED radiation and beyond-Standard-Model processes. We describe the principal features of the Ariadne, Herwig++, Pythia 8 and Sherpa generators, together with the Rivet and Professor validation and tuning tools, and discuss the physics philosophy behind the proper use of these generators and tools. This review is aimed at phenomenologists wishing to understand better how parton-level predictions are translated into hadron-level events as well as experimentalists wanting a deeper insight into the tools available for signal and background simulation at the LHC.

Buckley, Andy; /Edinburgh U.; Butterworth, Jonathan; /University Coll. London; Gieseke, Stefan; /Karlsruhe U., ITP; Grellscheid, David; /Durham U., IPPP; Hoche, Stefan; /SLAC; Hoeth, Hendrik; Krauss, Frank; /Durham U., IPPP; Lonnblad, Leif; /Lund U., Dept. Theor. Phys. /CERN; Nurse, Emily; /University Coll. London; Richardson, Peter; /Durham U., IPPP; Schumann, Steffen; /Heidelberg U.; Seymour, Michael H.; /Manchester U.; Sjostrand, Torbjorn; /Lund U., Dept. Theor. Phys.; Skands, Peter; /CERN; Webber, Bryan; /Cambridge U.

2011-03-03

233

General-purpose event generators for LHC physics  

Energy Technology Data Exchange (ETDEWEB)

We review the physics basis, main features and use of general-purpose Monte Carlo event generators for the simulation of proton-proton collisions at the Large Hadron Collider. Topics included are: the generation of hard scattering matrix elements for processes of interest, at both leading and next-to-leading QCD perturbative order; their matching to approximate treatments of higher orders based on the showering approximation; the parton and dipole shower formulations; parton distribution functions for event generators; non-perturbative aspects such as soft QCD collisions, the underlying event and diffractive processes; the string and cluster models for hadron formation; the treatment of hadron and tau decays; the inclusion of QED radiation and beyond Standard Model processes. We describe the principal features of the ARIADNE, Herwig++, PYTHIA 8 and SHERPA generators, together with the Rivet and Professor validation and tuning tools, and discuss the physics philosophy behind the proper use of these generators and tools. This review is aimed at phenomenologists wishing to understand better how parton-level predictions are translated into hadron-level events as well as experimentalists seeking a deeper insight into the tools available for signal and background simulation at the LHC.

Buckley, Andy [PPE Group, School of Physics and Astronomy, University of Edinburgh, EH25 9PN (United Kingdom); Butterworth, Jonathan [Department of Physics and Astronomy, University College London, WC1E 6BT (United Kingdom); Gieseke, Stefan [Institute for Theoretical Physics, Karlsruhe Institute of Technology, D-76128 Karlsruhe (Germany); Grellscheid, David [Institute for Particle Physics Phenomenology, Durham University, DH1 3LE (United Kingdom); Hoeche, Stefan [SLAC National Accelerator Laboratory, Menlo Park, CA 94025 (United States); Hoeth, Hendrik; Krauss, Frank [Institute for Particle Physics Phenomenology, Durham University, DH1 3LE (United Kingdom); Loennblad, Leif [Department of Astronomy and Theoretical Physics, Lund University (Sweden); PH Department, TH Unit, CERN, CH-1211 Geneva 23 (Switzerland); Nurse, Emily [Department of Physics and Astronomy, University College London, WC1E 6BT (United Kingdom); Richardson, Peter [Institute for Particle Physics Phenomenology, Durham University, DH1 3LE (United Kingdom); Schumann, Steffen [Institute for Theoretical Physics, University of Heidelberg, 69120 Heidelberg (Germany); Seymour, Michael H. [School of Physics and Astronomy, University of Manchester, M13 9PL (United Kingdom); Sjoestrand, Torbjoern [Department of Astronomy and Theoretical Physics, Lund University (Sweden); Skands, Peter [PH Department, TH Unit, CERN, CH-1211 Geneva 23 (Switzerland); Webber, Bryan, E-mail: webber@hep.phy.cam.ac.uk [Cavendish Laboratory, J.J. Thomson Avenue, Cambridge CB3 0HE (United Kingdom)

2011-07-15

234

Tsunami propagation modelling ? a sensitivity study  

Digital Repository Infrastructure Vision for European Research (DRIVER)

Indian Ocean (2004) Tsunami and following tragic consequences demonstrated lack of relevant experience and preparedness among involved coastal nations. After the event, scientific and forecasting circles of affected countries have started a capacity building to tackle similar problems in the future. Different approaches have been used for tsunami propagation, such as Boussinesq and Nonlinear Shallow Water Equations (NSWE). These approximations were obtained assuming different relevant importa...

Dao, M. H.; Tkalich, P.

2007-01-01

235

Development of a Probabilistic Tsunami Hazard Analysis Method and Application to an NPP in Korea  

Energy Technology Data Exchange (ETDEWEB)

A methodology of tsunami PSA was developed in this study. A tsunami PSA consists of tsunami hazard analysis, tsunami fragility analysis and system analysis. In the case of tsunami hazard analysis, evaluation of tsunami return period is a major task. For the evaluation of tsunami return period was evaluated with empirical method using historical tsunami record and tidal gauge record. For the performing a tsunami fragility analysis, procedure of tsunami fragility analysis was established and target equipment and structures for investigation of tsunami fragility assessment were selected. A sample fragility calculation was performed for the equipment in a Nuclear Power Plant. For the system analysis, accident sequence of tsunami event was developed according to the tsunami run-up and draw down, and tsunami induced core damage frequency (CDF) is determined. For the application to the real nuclear power plant, the Ulchin 56 NPP which is located on the east coast of Korean peninsula was selected. Through this study, whole tsunami PSA (Probabilistic Safety Assessment) working procedure was established and an example calculation was performed for one nuclear power plant in Korea.

Kim, M. K.; Choi, Ik [Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of)

2012-03-15

236

Development of a Probabilistic Tsunami Hazard Analysis Method and Application to an NPP in Korea  

International Nuclear Information System (INIS)

A methodology of tsunami PSA was developed in this study. A tsunami PSA consists of tsunami hazard analysis, tsunami fragility analysis and system analysis. In the case of tsunami hazard analysis, evaluation of tsunami return period is a major task. For the evaluation of tsunami return period was evaluated with empirical method using historical tsunami record and tidal gauge record. For the performing a tsunami fragility analysis, procedure of tsunami fragility analysis was established and target equipment and structures for investigation of tsunami fragility assessment were selected. A sample fragility calculation was performed for the equipment in a Nuclear Power Plant. For the system analysis, accident sequence of tsunami event was developed according to the tsunami run-up and draw down, and tsunami induced core damage frequency (CDF) is determined. For the application to the real nuclear power plant, the Ulchin 56 NPP which is located on the east coast of Korean peninsula was selected. Through this study, whole tsunami PSA (Probabilistic Safety Assessment) working procedure was established and an example calculation was performed for one nuclear power plant in Korea

2012-03-01

237

Hadron level event generation at NLO accuracy with Sherpa  

International Nuclear Information System (INIS)

Sherpa is a fully equipped tool for hadron level event generation for collider experiments. Using automated tree-level matrix element generators for the hard interaction and an automated matching with parton showers via the CKKW method, its accuracy is essentially limited to LO+NLL. Therefore, the next step is to extend the framework for computations at NLO accuracy in the hard interaction. While automatic generation of dipole subtraction terms is already available, the virtual contribution either is limited to a set of hard coded processes or needs to be fed in externally. Further, the parton showers need to be attached consistently, suitable also for multileg matching. In the talk a short review of the status of the framework for hadron level event generation at NLO+NLL accuracy will be given.

2010-03-15

238

Event-by-event generation of electromagnetic fields in heavy-ion collisions  

CERN Document Server

We compute the electromagnetic fields generated in heavy-ion collisions by using HIJING model. Although after averaging over many events only the magnetic field perpendicular to the reaction plane is sizable, we find very strong magnetic and electric fields both parallel and perpendicular to the reaction plane on the event-by-event basis. We study the time evolution and the spatial distribution of these fields. Especially, the electromagnetic response of the QGP can give non-trivial evolution of the electromagnetic fields. The implications of the strong electromagnetic fields on the hadronic observables are also discussed

Deng, Wei-Tian

2012-01-01

239

Event tree analysis for steam generator tube ruptures  

International Nuclear Information System (INIS)

The probabilistic safety analysis on steam generator tube ruptures in nuclear power plants is presented. The reactor core melt frequencies 1.26 x 10-6/a reactor resulted from 1 to 2 steam generator tube ruptures during power operation are shown, and the dominant accident sequences are also given. The importance of simulation training on timely operators' interventions in the event is stressed

1999-04-01

240

Developing tsunami fragility curves based on the satellite remote sensing and the numerical modeling of the 2004 Indian Ocean tsunami in Thailand  

Digital Repository Infrastructure Vision for European Research (DRIVER)

The 2004 Indian Ocean tsunami damaged and destroyed numerous buildings and houses in Thailand. Estimation of tsunami impact to buildings from this event and evaluation of the potential risks are important but still in progress. The tsunami fragility curve is a function used to estimate the structural fragility against tsunami hazards. This study was undertaken to develop fragility curves using visual inspection of high-resolution satellite images (IKONOS) taken before and af...

Suppasri, A.; Koshimura, S.; Imamura, F.

2011-01-01

 
 
 
 
241

Monte Carlo event generators for hadron-hadron collisions  

International Nuclear Information System (INIS)

A brief review of Monte Carlo event generators for simulating hadron-hadron collisions is presented. Particular emphasis is placed on comparisons of the approaches used to describe physics elements and identifying their relative merits and weaknesses. This review summarizes a more detailed report

1993-06-02

242

Tsunami Risk and Vulnerability  

Digital Repository Infrastructure Vision for European Research (DRIVER)

The research focuses on providing reliable spatial information in support of tsunami risk and vulnerability assessment within the framework of the German-Indonesian Tsunami Early Warning System (GITEWS) project. It contributes to three major components of the project: (1) the provision of spatial information on surface roughness as an important parameter for tsunami inundation modeling and hazard assessment; (2) the modeling of population distribution, which is an essential factor in tsunami ...

2010-01-01

243

Input in Tsunami Hazard for Far-East Coast of Russia from Regional and Far-Field Sources  

Science.gov (United States)

The Probabilistic Tsunami Hazard Assessment (PTHA) methodology, having many features similar to the Probabilistic Seismic Hazard Assessment (PSHA) methodology, differs from the latter in one important relation - far-field sources, ignored in PSHA, in some cases can be of great importance in PTHA. Tsunami hazard assessment for the Far East coast of Russia gives a typical example of this situation. While regional tsunamigenic earthquakes located along the Kuril-Kamchatka subduction zone and in the eastern part of the Sea of Japan represent the major hazard, most part of this coast is open to tsunami impact from other tsunamigenic regions of the Pacific, and, first of all, from the sources near South America. Analysis of real historical data shows that during the last 50 years only three far-field tsunamis (1960 Chilean, 1964 Alaska and 2011Tohoku) produced dangerous impact along the Far East coast of Russia. However, during this period 19 regional tsunami warnings were issued in relation to far-field tsunamigenic sources, 16 of them turned out to be false. This statistic shows that the problem of far-field sources is worth of a special consideration in relation to Far-East coast of Russia. The results of numerical modeling show that the real threat can come only from M9 class mega-events in the far-field. Tsunami run-up height expected from such events along the Kurile-Kamchatka coast can reach 4-5 m, however, its actual value strongly depends on the position and orientation of a far-field source relatively the region. In general, the expected maximum heights from far-field sources (up to 6 m) are not so large as possible maximum heights from the regional earthquakes with magnitudes M7.5-8.5 (15-20 m), however, the waves from trans-Pacific tsunamis affect all parts of the Far-East coastline. Another feature of far-field tsunamis is that the duration of dangerous sea level oscillations can be considerably longer (up to 48 hours) and the maximum height can be observed much later (on 12-24 hours) the ETA (Expected Tsunami Arrival) time. This affect (delay of maximum height against the ETA time) is most common for the coast of marginal seas, like Okhotsk and Bering Seas. The paper analyses historical cases of impact of far-field tsunamis on the Kuril-Kamchatka coast of Russia and statistics of warnings issued by the regional TWS in 1958-2012. We compare these data with the results of numerical modeling of trans-Pacific tsunamis generated by Mw9.0 model sources distributed over the main Pacific tsunamigenic zones.

Gusiakov, V. K.; Beisel, S. A.; Chubarov, L. B.

2013-12-01

244

Feasibility of Tsunami Early Warning Systems for small volcanic islands  

Digital Repository Infrastructure Vision for European Research (DRIVER)

This paper investigates the feasibility of Tsunami Early Warning Systems for small volcanic islands focusing on warning of waves generated by landslides at the coast of the island itself. The critical concern is if there is enough time to spread the alarm once the system has recognized that a tsunami has been generated. We use the results of a large scale physical model experiment in order to estimate the time that tsunamis take to travel around the island inundating the coa...

Bellotti, G.; Di Risio, M.; Girolamo, P.

2009-01-01

245

Plate Boundary Observatory Strain Recordings of the February 27, 2010, M8.8 Chile Tsunami  

Science.gov (United States)

In the hours that followed the February 27, 2010 M8.8 Chile earthquake a tsunami swept across the Pacific Ocean causing alerts to be issued from Antarctica to Alaska. PBO borehole strainmeters, at Ucluelet, Bamfield and Port Alberni, on Vancouver Island, Canada, recorded the arrival of the tsunami along the British Columbia coastline. In this presentation we describe the nature of the strain signal generated by the February 27, 2010 tsunami and compare it to seismic, GPS, pore-pressure, barometric pressure and tide gauge measurements made at or near the PBO borehole installations. The Ucluelet and Bamfield strainmeters, on the west coast of Vancouver Island, recorded the arriving waves ~ 16.5 hours after the M8.8 earthquake. The Port Alberni strainmeter, located on the northeast end of Alberni Inlet, a 1-2 km wide and 40 km long fjord recorded the first waves ~45 minutes later. The Ucluelet and Bamfield strainmeter arrival times are consistent with tide gauge measurements made at Tofino, 30 km north of Ucluelet. Areal strain amplitudes of up to 15 to 20 nanostrain were recorded at the three strainmeters and significant tsunami oscillations persisted for days. A PBO strainmeter 2.5 km from the Oregon coast did record a tsunami related signal though it was much smaller than at the three Vancouver Island sites. The Oregon site thus provides information on the attenuation of the signal with distance from the coastline. The ability of the strainmeters to record the tsunami signals following the 2010 M8.8 Chile and 2009 M8.1 Samoa events suggest they, or possibly less costly borehole tiltmeters, could be used as land-based instruments to record tsunami arrival times and provide estimates of wave heights.

Hodgkinson, Kathleen; Mencin, Dave; Borsa, Adrian; Jackson, Mike

2010-05-01

246

Plate Boundary Observatory Borehole Strainmeter Recordings Of The 29 September 2009 Tsunami  

Science.gov (United States)

On 29 September 2009 a M8.3 earthquake on the Australian-Pacific plate boundary generated a tsunami that caused widespread damage in Samoa, American Samoa, and Tonga. Peak to trough wave heights of 314 cm were recorded 250 km from the epicenter at Pago-Pago, American Samoa approximately 20 minutes after the event. NOAA's West Coast and Alaska Tsunami Warning Center predicted the tsunami would arrive at Tofino, Vancouver Island, British Columbia, at 05:12 UTC, 30 September 2009. The Plate Boundary Observatory has installed 74 borehole strainmeters along the western United States for the purpose of recording short-term strain transients associated with plate boundary deformation. Two of these strainmeters, Ucluelet and Bamfield, are located on the west coast of Vancouver Island within a few hundred meters of the shore. A third, Port Alberni, is located at the eastern end of Port Alberni Inlet, ~ 50 km inland. The Ucluelet and Bamfield strainmeters recorded signals associated with the arriving tsunami at times consistent with that recorded by tide gauges at Tofino and Bamfield, ~05:45 UTC. A much smaller signal was recorded about 24 minutes later at Port Alberni. The tsunami strain signals were below the detection level of PBO GPS on the Oregon coast and seismometers in the strainmeter boreholes. Strainmeters, or lower coast tiltmeters, could potentially, provide a reliable onshore detection of a tsunami. In this presentation we document the nature and frequency content of the tsunami signal as recorded by PBO strainmeters and compare these strain measurements against the crustal loading signature predicted by water height changes at nearby tide gauges

Hodgkinson, Kathleen; Mencin, David; Borsa, Adrian; Jackson, Mike

2010-05-01

247

IMPACT OF TSUNAMI 2004 IN COASTAL VILLAGES OF NAGAPATTINAM DISTRICT, INDIA  

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Full Text Available ABSTRACTA quake-triggered tsunami lashed the Nagapattinam coast of southern India on December 26, 2004 at around 9.00 am (IST. The tsunami caused heavy damage to houses, tourist resorts, fishing boats, prawn culture ponds, soil and crops, and consequently affected the livelihood of large numbers of the coastal communities. The study was carried out in the Tsunami affected villages in the coastal Nagapattinam with the help of remote sensing and geographical information science tools. Through the use of the IRS 1D PAN and LISS 3 merged data and quick bird images, it was found that 1,320 ha of agricultural and non-agricultural lands were affected by the tsunami. The lands were affected by soil erosion, salt deposition, water logging and other deposited sediments and debris. The maximum run-up height of 6.1 m and the maximum seawater inundation distance of 2.2 km were observed at Vadakkupoyyur village in coastal Nagapattinam.Pre and Post Tsunami survey on soil quality showed an increase in pH and EC values, irrespectiveof distance from the sea. The water reaction was found to be in alkaline range (> 8.00 in most of the -1wells. Salinity levels are greater than 4 dS m in all the wells except the ring well. The effect of summer rainfall on soil and water quality showed the dilution of soluble salts. Pumping of water has reduced the salinity levels in the well water samples and as well as in the open ponds. Following the 2004 event, it has become apparent to know the relative tsunami hazard for this coastal Nagapattinam. So, the Tsunami hazard maps are generated using a geographical information systems (GIS approach and the results showed 20.6 per cent, 63.7 per cent and 15.2 per cent of the study area fall under high hazard, medium hazard and low hazard category respectively.

R. Kumaraperumal

2007-01-01

248

Tsunami hazard and risk assessment in El Salvador  

Science.gov (United States)

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 arrival time, maximum flooding level or "Run-up", hazard degree for people based on incipient velocity for people instability) along the coast of El Salvador and at some relevant locations (high resolution analysis). The VULNERABILITY assessment of the exposed elements (Phase II of the project) is based on an integrated approach which is essential given the complexity of coastal areas. A set of indices and indicators have been developed supported by a Geographic Information System that allows graphical representation of physical, environmental, social, economic and infrastructure characteristics of the coast. Different spatial and temporal scales have been also considered in this project to calculate the risk, since both factors would change the amount and type of exposed elements and their vulnerability. A final global RISK analysis (hazard, exposure and vulnerability analysis for each dimension -human, environmental, socioeconomic and infrastructure- and both temporal and spatial scales) allows identifying weaknesses, gaps and special needs to cope with a tsunami event and, therefore, will result in a set of risk reduction measures, including adaptation and mitigation measures.

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

249

MARINE CONGLOMERATE AND REEF MEGACLASTS AT MAURITUS ISLAND: Evidences of a tsunami generated by a flank collapse of the PITON DE LA Fournaise volcano, Reunion Island?  

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Full Text Available Tsunamis related to volcano flank collapse are typically a high-magnitude, low frequency hazard for which evaluation and mitigation are difficult to address. In this short communication, we present field evidences of a large tsunami along the southern coast of Mauritius Island ca. 4400 years ago. Tsunami deposits described include both marine conglomerates and coral boulders up to 90 m3 (> 100 tons. The most probable origin of the tsunami is a flank collapse of Piton de la Fournaise volcano, Réunion Island.

R. Paris

2014-05-01

250

Transient Tsunamis in Lakes  

Science.gov (United States)

A large number of lakes are surrounded by steep and unstable mountains with slopes prone to failure. As a result, landslides are likely to occur and impact water sitting in closed reservoirs. These rare geological phenomena pose serious threats to dam reservoirs and nearshore facilities because they can generate unexpectedly large tsunami waves. In fact, the tallest wave experienced by contemporary humans occurred because of a landslide in the narrow bay of Lituya in 1958, and five years later, a deadly landslide tsunami overtopped Lake Vajont's dam, flooding and damaging villages along the lakefront and in the Piave valley. If unstable slopes and potential slides are detected ahead of time, inundation maps can be drawn to help people know the risks, and mitigate the destructive power of the ensuing waves. These maps give the maximum wave runup height along the lake's vertical and sloping boundaries, and can be obtained by numerical simulations. Keeping track of the moving shorelines along beaches is challenging in classical Eulerian formulations because the horizontal extent of the fluid domain can change over time. As a result, assuming a solid slide and nonbreaking waves, here we develop a nonlinear shallow-water model equation in the Lagrangian framework to address the problem of transient landslide-tsunamis. In this manner, the shorelines' three-dimensional motion is part of the solution. The model equation is hyperbolic and can be solved numerically by finite differences. Here, a 4th order Runge-Kutta method and a compact finite-difference scheme are implemented to integrate in time and spatially discretize the forced shallow-water equation in Lagrangian coordinates. The formulation is applied to different lake and slide geometries to better understand the effects of the lake's finite lengths and slide's forcing mechanism on the generated wavefield. Specifically, for a slide moving down a plane beach, we show that edge-waves trapped by the shoreline and free-waves moving away from it coexist. On an open coast, these two types of waves would never interact, but because of the lake's finite dimensions, here we show that local inundation height maxima are due to wave superposition on the shoreline. These interactions can be dramatic near the lake's corners. For instance, in a rectangular lake delimited by two opposite and plane beaches and two vertical walls, we find that a landslide tsunami results in an inundation height at a corner 50% larger than anywhere else. The nonlinear and linear models produce different inundation maps, and here we show that maximum wave runups can be increased by up to 56% when nonlinear terms are included.

Couston, L.; Mei, C.; Alam, M.

2013-12-01

251

Quakes and tsunamis detected by GOCE  

Science.gov (United States)

The aerodynamic accelerations measured by GOCE are used to calculate air density variations and air velocity estimates along GOCE orbit track. The detection of infrasonic waves generated by seismic surface waves and gravity waves generated by tsunamis are presented for earthquakes and tsunamis generated by the great Tohoku quake (11/03/2011). For the seismic/infrasonic waves, a wave propagation modelling is presented and synthetic data are compared to GOCE measurements. The travel time and amplitude discrepancies are discussed in terms of lateral velocity variations in the solid Earth and the atmosphere. For the tsunami/gravity waves, a plane wave analysis is performed and relations between vertical velocity, cross-track velocity and density variations are deduced. From theoretical relations between air density, and vertical and horizontal velocities inside the gravity wave, we demonstrate that the measured perturbations are consistent with a gravity wave generated by the tsunami, and provide a way to estimate the propagation azimuth of the gravity wave. By using these relations, an indicator of gravity wave presence is constructed. It will allow to scan the GOCE data set to search for gravity wave crossings. This study demonstrates that very low earth orbit spacecraft with high-resolution accelerometers are able to detect atmospheric waves generated by the tectonic activity. Such spacecraft may supply additional data to tsunami alert systems in order to validate some tsunami alerts.

Garcia, Raphael F.; Doornbos, Eelco; Bruinsma, Sean; Hebert, Hélène

2014-05-01

252

Two new ESSEA Modules: (1) Pacific Influences on Climatic Change and Variability and (2) Assessment of Tsunami Hazards  

Science.gov (United States)

The CSULA Departments of Geography and Geological Sciences, in cooperation with the Charter College of Education at CSULA, propose to introduce the Earth System Science Education Alliance (ESSEA) On-line course for middle school teachers as a section of our undergraduate pre-service teacher course, PSCI 183: Earth Science for Elementary Teachers. Physical Science 183 was proposed as an activities and inquiry- based course for students needing an earth science foundation, but in an active learning environment. We have developed two ESSEA education modules centered on climate change and natural variability and on tsunami. The climate change module is based on a scenario in which students are part of a climate change advisory committee charged with providing the scientific framework for climate change. Students learn to distinguish between natural variability in the Pacific Ocean and trends in global climate change. Components of the module focus on interpreting trends in temperature, precipitation, and sea surface temperatures and heights using datasets using NOAA websites. Quantitative analysis of the trends reveals patterns related to the Pacific Decadal Oscillation, El Niño/La Niña events, and global climate change. Identification of patterns and trends facilitate forecasting of southern California temperature and precipitation and allow policy development addressing the changing climate. Tsunami are repetitive, potentially destructive natural hazards impacting people across the globe. The tsunami module asks student to provide representatives of western US states with an assessment of tsunami risks. Through the exercise students learn what tsunami are, the tectonic connection to tsunami generation, tsunami wave characteristics and strategies for the development of a tsunami warning system.

Ladochy, S.; Ramirez, P.; Patzert, W. C.

2008-12-01

253

Geomorphic Environments of Tsunami Deposits, Southeastern India  

Science.gov (United States)

As paleotsunami research progresses around the Indian Ocean, it is increasingly evident that tsunamis have occurred in this region in the past. The largest of these could have traversed the ocean and reached the southeastern coast of India, which highlights the importance of identifying key preservation sites in this potential repository of catastrophic basin-wide events. However, geologically enduring sites where tsunami deposits dependably survive are not yet well defined in India and other tropical environments. The purpose of this project was to identify the settings conducive to long-term preservation of tsunami deposits in tropical India and develop criteria for distinguishing them in the stratigraphic record. We documented the post- depositional fate of the tsunami deposits from the 2004 Sumatra-Andaman earthquake in various geomorphic environments along the southeastern coast of Tamil Nadu, India from 10.5-13° N. Latitude. Deposits from the 2004 tsunami were mapped, described and surveyed at locations where they had been described immediately after the event, as well as at previously unstudied sites. At many sites, the tsunami deposits were recognizable in the stratigraphic column by characteristic fine mafic laminations, debris and an organic layer at the lower boundary. Field observations and initial grain-size analysis indicated a distinct difference between tsunami deposits and underlying sedimentary layers. For example, at Mamallapuram (12.5° N. Lat.) the mean grain size of the tsunami deposits was 0.25 phi finer than that of the underlying layers. However, only three years after the event, deposits in some locations had already been altered significantly by erosion, bioturbation and incipient weathering and were not readily recognizable in the stratigraphy. Although the 2004 tsunami deposits were thicker and more extensive in the hard-hit southern half of the study area, the degree of bioturbation and weathering was greater there than in the drier northern portion, where some thin tsunami sand layers behind coastal dunes remained unaltered since the original post- tsunami surveys. To date, no conclusive evidence of paleotsunami deposits has been found at the sites included in this study, but the results will guide the search for key settings that best satisfy the balance between sediment volume and preservation.

Johnston, P.; Ely, L.; Achyuthan, H.; Srinivasalu, S.

2008-12-01

254

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

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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.

Giovanni Franchello

2012-01-01

255

SAGE CALCULATIONS OF THE TSUNAMI THREAT FROM LA PALMA  

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Full Text Available With the LANL multiphysics hydrocode SAGE, we have performed several two-dimensional calculations and one three-dimensional calculation using the full Navier-Stokes equations, of a hypothetical landslide resembling the event posited by Ward and Day (2001, a lateral flank collapse of the Cumbre Vieja Volcano on La Palma that would produce a tsunami. The SAGE code has previously been used to model the Lituya Bay landslide-generated tsunami (Mader & Gittings, 2002, and has also been used to examine tsunami generation by asteroid impacts (Gisler, Weaver, Mader, & Gittings, 2003. This code uses continuous adaptive mesh refinement to focus computing resources where they are needed most, and accurate equations of state for water, air, and rock. We find that while high-amplitude waves are produced that would be highly dangerous to nearby communities (in the Canary Islands, and the shores of Morocco, Spain, and Portugal, the wavelengths and periods of these waves are relatively short, and they will not propagate efficiently over long distances.

Galen Gisler

2006-01-01

256

The 2010 Chilean Tsunami Off the West Coast of Canada and the Northwest Coast of the United States  

Science.gov (United States)

The major ( M w = 8.8) Chilean earthquake of 27 February 2010 generated a trans-oceanic tsunami that was observed throughout the Pacific Ocean. Waves associated with this event had features similar to those of the 1960 tsunami generated in the same region by the Great ( M w = 9.5) 1960 Chilean Earthquake. Both tsunamis were clearly observed on the coast of British Columbia. The 1960 tsunami was measured by 17 analog pen-and-paper tide gauges, while the 2010 tsunami was measured by 11 modern digital coastal tide gauges, four NEPTUNE-Canada bottom pressure recorders located offshore from southern Vancouver Island, and two nearby open-ocean DART stations. The 2010 records were augmented by data from seven NOAA tide gauges on the coast of Washington State. This study examines the principal characteristics of the waves from the 2010 event (height, period, duration, and arrival and travel times) and compares these properties for the west coast of Canada with corresponding properties of the 1960 tsunami. Results show that the 2010 waves were approximately 3.5 times smaller than the 1960 waves and reached the British Columbia coast 1 h earlier. The maximum 2010 wave heights were observed at Port Alberni (98.4 cm) and Winter Harbour (68.3 cm); the observed periods ranged from 12 min at Port Hardy to 110-120 min at Prince Rupert and Port Alberni and 150 min at Bamfield. The open-ocean records had maximum wave heights of 6-11 cm and typical periods of 7 and 15 min. Coastal and open-ocean tsunami records revealed persistent oscillations that "rang" for 3-4 days. Tsunami energy occupied a broad band of periods from 3 to 300 min. Estimation of the inverse celerity vectors from cross-correlation analysis of the deep-sea tsunami records shows that the tsunami waves underwent refraction as they approached the coast of Vancouver Island with the direction of the incoming waves changing from an initial direction of 340° True to a direction of 15° True for the second train of waves that arrived 7 h later after possible reflection from the Marquesas and Hawaiian islands.

Rabinovich, Alexander B.; Thomson, Richard E.; Fine, Isaac V.

2013-09-01

257

Optical Dating of Tsunami-Laid Sands  

Science.gov (United States)

The ages of some tsunami deposits can be determined by optical dating, a key requirement being that the deposits are derived from sediment that was reworked and exposed to daylight by tidal currents, waves, wind, or bioturbation during the last years before the tsunami. Measurements have been made using 1.4 eV (infrared) excitation of K-feldspar grains separated from samples of prehistoric tsunami sand sheets and modern analogs of tsunami source sediments at four sites in Washington state and British Columbia. Source sands gave equivalent doses indicative of recent exposure to daylight. Tsunami sand at Cultus Bay, Washington, yielded an optical age of 1285 ± 95 yr (calendric years before A.D. 1995, ±1?). At 2?, this age overlaps the range of from 1030 to 1100 yr determined through a combination of high-precision radiocarbon dating and stratigraphic correlation. Tsunami sands at three sites near Tofino and Port Alberni on Vancouver Island, British Columbia, have optical ages of 260 ± 20, 325 ± 25, and 335 ± 45 yr. Historical records and radiocarbon dating show that the sand at each of the three sites is between 150 and 400 yr old. These optical ages support the hypothesis that the Vancouver Island sands were deposited by a tsunami generated by a large earthquake on the Cascadia subduction zone about 300 yr ago.

Huntley, David J.; Clague, John J.

1996-09-01

258

Title: Dispersive tsunamis; does it really matter?  

Science.gov (United States)

Most tsunami modelers rely on the shallow water equations for predictions of propagation and runup, either by using one of the standard codes or by means of an in-house code. Some groups, on the other hand, insist on applying dispersive wave models, sometimes even with enhanced nonlinear properties. Dispersive models are also available as standard code, free or commercial, and some of these are fairly well suited for implementation of tsunami applications. Whereas the employment of dispersive codes for tsunami computation certainly boost the CPU times and memory requirements the gains are regarded as more uncertain by many in the tsunami community. It is clear that physical effects like frequency dispersion and formation of undular bores are beyond the shallow water theory. In this talk we draw on the experience from a series of earthquake and landslide tsunamis to address the significance of dispersion. While frequency dispersion is generally important for tsunamis generated by both submarine and subaerial landslides, the effect is apparent also for tsunamis of seismic origin, albeit to a lesser extent. The source dimensions, water depth and propagation distance all combine to determine the effect of dispersion in deep water propagation. Undular bores do also evolve under given conditions. However, their effect on inundation is still uncertain.

Pedersen, G. K.; Løvholt, F.; Glimsdal, S.; Harbitz, C. B.

2012-04-01

259

Towards a certification process for tsunami early warning systems  

Science.gov (United States)

The natural disaster of the Boxing Day Tsunami of 2004 was followed by an information catastrophe. Crucial early warning information could not be delivered to the communities under imminent threat, resulting in over 240,000 casualties in 14 countries. This tragedy sparked the development of a new generation of integrated modular Tsunami Early Warning Systems (TEWS). While significant advances were accomplished in the past years, recent events, like the Chile 2010 and the Tohoku 2011 tsunami demonstrate that the key technical challenge for Tsunami Early Warning research on the supranational scale still lies in the timely issuing of status information and reliable early warning messages in a proven workflow. A second challenge stems from the main objective of the Intergovernmental Oceanographic Commission of UNESCO (IOC) Tsunami Programme, the integration of national TEWS towards ocean-wide networks: Each of the increasing number of integrated Tsunami Early Warning Centres has to cope with the continuing evolution of sensors, hardware and software while having to maintain reliable inter-center information exchange services. To avoid future information catastrophes, the performance of all components, ranging from individual sensors, to Warning Centers within their particular end-to-end Warning System Environments, and up to federated Systems of Tsunami Warning Systems has to be regularly validated against defined criteria. Since 2004, GFZ German Research Centre for Geosciences (GFZ) has built up expertise in the field of TEWS. Within GFZ, the Centre for GeoInformation Technology (CeGIT) has focused its work on the geoinformatics aspects of TEWS in two projects already, being the German Indonesian Tsunami Early Warning System (GITEWS) and the Distant Early Warning System (DEWS). This activity is continued in the TRIDEC project (Collaborative, Complex, and Critical Decision Processes in Evolving Crises) funded under the European Union's seventh Framework Programme (FP7). TRIDEC focuses on real-time intelligent information management in Earth management and its long-term application: The technical development is based on mature system architecture models and industry standards. The use of standards already applies to the operation of individual TRIDEC reference installations and their interlinking into an integrated service infrastructure for supranational warning services. This is a first step towards best practices and service lifecycles for Early Warning Centre IT service management, including Service Level Agreements (SLA) and Service Certification. While on a global scale the integration of TEWS progresses towards Systems of Systems (SoS), there is still an absence of accredited and reliable certifications for national TEWS or regional Tsunami Early Warning Systems of Systems (TEWSoS). Concepts for TEWS operations have already been published under the guidance of the IOC, and can now be complemented by the recent research advances concerning SoS architecture. Combined with feedback from the real world, such as the NEAMwave 2012 Tsunami exercise in the Mediterranean, this can serve as a starting point to formulate initial requirements for TEWS and TEWSoS certification: Certification activities will cover the establishment of new TEWS and TEWSoS, and also both maintenance and enhancement of existing TEWS/TEWSoS. While the IOC is expected to take a central role in the development of the certification strategy, it remains to be defined which bodies will actually conduct the certification process. Certification requirements and results are likely to become a valuable information source for various target groups, ranging from national policy decision makers, government agency planners, national and local government preparedness officials, TWC staff members, Disaster Responders, the media and the insurance industry.

Löwe, Peter; Wächter, Jochen; Hammitzsch, Martin

2013-04-01

260

DID A SUBMARINE SLIDE TRIGGER THE 1918 PUERTO RICO TSUNAMI?  

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Full Text Available The 1918 tsunami that inundated northwest Puerto Rico with up to 6 m waves has been attributed to seafloor faulting associated with the 1918 Mona Canyon earthquake. During the earthquake a series of submarine cable breaks occurred directly off the northwest coast of Puerto Rico where the largest tsunami waves came ashore. Here, we use a recently compiled geophysical data set to reveal that a 9 km long landslide headwall exists in the region where cable breaks occurred during the 1918 earthquake. We incorporate our interpretations into a near-field tsunami wave model to evaluate whether the slide may have triggered the observed 1918 tsunami. Our analysis indicates that this slide could generate a tsunami with phase, arrival times, and run-ups similar to observations along the northwest coast of Puerto Rico. We therefore suggest that a submarine slide offers a plausible alternative explanation for generation of this large tsunami.

Matthew J. Hornbach

2008-01-01

 
 
 
 
261

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

Science.gov (United States)

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.

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

2013-12-01

262

Specification of Tectonic Tsunami Sources Along the Eastern Aleutian Island Arc and Alaska Peninsula for Inundation Mapping and Hazard Assessment  

Science.gov (United States)

The Alaska Earthquake Information Center conducts tsunami inundation mapping for coastal communities in Alaska along several segments of the Aleutian Megathrust, each having a unique seismic history and tsunami generation potential. Accurate identification and characterization of potential tsunami sources is a critical component of our project. As demonstrated by the 2011 Tohoku-oki tsunami, correct estimation of the maximum size event for a given segment of the subduction zone is particularly important. In that event, unexpectedly large slip occurred approximately updip of the epicenter of the main shock, based on seafloor GPS and seafloor pressure gage observations, generating a much larger tsunami than anticipated. This emphasizes the importance of the detailed knowledge of the region-specific subduction processes, and using the most up-to-date geophysical data and research models that define the magnitude range of possible future tsunami events. Our study area extends from the eastern half of the 1957 rupture zone to Kodiak Island, covering the 1946 and 1938 rupture areas, the Shumagin gap, and the western part of the 1964 rupture area. We propose a strategy for generating worst-case credible tsunami scenarios for locations that have a short or nonexistent paleoseismic/paleotsunami record, and in some cases lack modern seismic and GPS data. The potential tsunami scenarios are built based on a discretized plate interface model fit to the Slab 1.0 model geometry. We employ estimates of slip deficit along the Aleutian Megathrust from GPS campaign surveys, the Slab 1.0 interface surface, empirical magnitude-slip relationships, and a numerical code that distributes slip among the subfault elements, calculates coseismic deformations and solves the shallow water equations of tsunami propagation and runup. We define hypothetical asperities along the megathrust and in down-dip direction, and perform a set of sensitivity model runs to identify coseismic deformation patterns resulting in highest runup at a given community. Because of the extra fine discretization of the interface, we can prescribe variable slip patterns, using simple parameters to describe slip variations in the along-strike and down-dip directions. Since it was demonstrated by studies of the 1964 tsunami that changes in slip distribution result in significant variations in the local tsunami wave field, we expect that the near-field tsunami runup in target communities will be highly sensitive to variability of slip along the rupture area. We perform simulations for each source scenario using AEIC's numerical model of tsunami propagation and runup, which is validated through a set of analytical benchmarks and tested against laboratory and field data. Results of numerical modeling combined with historical observations are compiled on inundation maps and used for site-specific tsunami hazard assessment by local emergency planners.

Suleimani, E.; Nicolsky, D.; Freymueller, J. T.; Koehler, R.

2013-12-01

263

UNDERSTANDING TSUNAMI RISK TO STRUCTURES: A CANADIAN PERSPECTIVE  

Directory of Open Access Journals (Sweden)

Full Text Available The potential catastrophic effects of tsunami-induced loading on built infrastructure in the vicinity of shorelines have been brought to the fore by recent global events. However, state- of-the-art building codes remain silent or provide conflicting guidance on designing near- shoreline structures in tsunami-prone areas. This paper focuses on tsunami-induced loading and its effect on structures within the Canadian context. The mechanics of tsunami-induced loading is described based on knowledge gained during reconnaissance visits after the 2004 south-east Asia Tsunami, as well as post-construction visits to countries significantly affected by the destructive forces of the tsunami. To gain an appreciation of the magnitude of tsunami-induced bores for a given seismic event along the western coastal region of Canada, structural analysis of a simple near-shoreline structure was performed considering a proposed loading protocol for tsunami-induced hydraulic bores. These loads were further compared to seismic loading in order to provide an estimation of the tsunami risk and its impact. The work was complemented by experimental results from a large-scale testing program conducted with the purpose of estimating the forces experienced on structural components. Square-, rectangular-, and diamond-shaped columns were used to study the influence of shape. Furthermore, results from debris impact testing are also discussed.

D. Palermo

2008-01-01

264

Art Therapy with Child Tsunami Survivors in Sri Lanka  

Science.gov (United States)

This paper details art therapy with children affected by the December 2004 tsunami in Sri Lanka. Over 30,000 Sri Lankans lost their lives when the tsunami decimated coastal areas. The child survivors witnessed horrific traumatic events and the loss of loved ones, but had not been given opportunity to express their grief and pain. A 4-week art…

Chilcote, Rebekah L.

2007-01-01

265

Simulation of multiple Steam Generator Tube Rupture (SGTR) event scenario  

Energy Technology Data Exchange (ETDEWEB)

The multiple Steam Generator Tube Rupture (SGTR) event scenario with available safety systems was experimentally and analytically evaluated. The experiment was conducted on the large scaled test facility to simulate the multiple SGTR event and investigate the effectiveness of operator actions. As a result, it indicated that the opening of pressurizer power operated relief valve was significantly effective in quickly terminating the primary-to-secondary break flow even for the 6.5 tubes rupture. In the analysis, the recent version of RELAP5 code was assessed with the test data. It indicated that the calculations agreed well with the measured data and that the plant responses such as the water level and relief valve cycling in the damaged steam generator were reasonably predicted. Finally, sensitivity study on the number of ruptured tubes up to 10 tubes was performed to investigate the coolant release into atmosphere. It indicated that the integrated steam mass released was not significantly varied with the number of ruptured tubes although the damaged steam generator was overfilled for more than 3 tubes rupture. These findings are expected to provide useful information in understanding and evaluating the plant ability to mitigate the consequence of multiple SGTR event.

Seul, Kwang Won; Bang, Young Seok; Kim, In Goo [KINS, Taejon (Korea, Republic of); Yonomoto, Taisuke; Anoda, Yoshinari [Japan Atomic Energy Research Institute, Ibaraki (Japan)

2003-06-01

266

Simulation of multiple Steam Generator Tube Rupture (SGTR) event scenario  

International Nuclear Information System (INIS)

The multiple Steam Generator Tube Rupture (SGTR) event scenario with available safety systems was experimentally and analytically evaluated. The experiment was conducted on the large scaled test facility to simulate the multiple SGTR event and investigate the effectiveness of operator actions. As a result, it indicated that the opening of pressurizer power operated relief valve was significantly effective in quickly terminating the primary-to-secondary break flow even for the 6.5 tubes rupture. In the analysis, the recent version of RELAP5 code was assessed with the test data. It indicated that the calculations agreed well with the measured data and that the plant responses such as the water level and relief valve cycling in the damaged steam generator were reasonably predicted. Finally, sensitivity study on the number of ruptured tubes up to 10 tubes was performed to investigate the coolant release into atmosphere. It indicated that the integrated steam mass released was not significantly varied with the number of ruptured tubes although the damaged steam generator was overfilled for more than 3 tubes rupture. These findings are expected to provide useful information in understanding and evaluating the plant ability to mitigate the consequence of multiple SGTR event

2003-06-01

267

e+e- event generator EPOCS user's manual  

International Nuclear Information System (INIS)

EPOCS(Electron POsitron Collision Simulator) is a Monte-Carlo event generator for high energy e+e- annihilation. This program generates events based on the standard model, i.e., quantum chromodynamics (QCD) and electro-weak theory. It works at the center-of-mass energy below W+W- production, i.e., in the energy region of TRISTAN, SLC and LEP. For these high energy machines one of the important subjects is the exploration for the top quark. The production and hadronization of the top quark is included in EPOCS. Besides the top quark, we expect 'new' physics in this high energy region. EPOCS has enough flexibility for users to cope with a new idea. Users can register a new particle, modify the built-in particle data, define new primary interactions and so on. The event generator has a number of parameters, both physical parameters and control parameters. Users can control most of these parameters in EPOCS at will. (author)

1987-01-01

268

New Tsunami Inundation Maps for California  

Science.gov (United States)

California is the first US State to complete its tsunami inundation mapping. A new generation of tsunami inundation maps is now available for 17 coastal counties.. The new maps offer improved coverage for many areas, they are based on the most recent descriptions of potential tsunami farfield and nearfield sources and use the best available bathymetric and topographic data for modelling. The need for new tsunami maps for California became clear since Synolakis et al (1998) described how inundation projections derived with inundation models that fully calculate the wave evolution over dry land can be as high as twice the values predicted with earlier threshold models, for tsunamis originating from tectonic source. Since the 1998 Papua New Guinea tsunami when the hazard from offshore submarine landslides was better understood (Bardet et al, 2003), the State of California funded the development of the first generation of maps, based on local tectonic and landslide sources. Most of the hazard was dominated by offshore landslides, whose return period remains unknown but is believed to be higher than 1000 years for any given locale, at least in Southern California. The new generation of maps incorporates local and distant scenarios. The partnership between the Tsunami Research Center at USC, the California Emergency Management Agency and the California Seismic Safety Commission let the State to be the first among all US States to complete the maps. (Exceptions include the offshore islands and Newport Beach, where higher resolution maps are under way). The maps were produced with the lowest cost per mile of coastline, per resident or per map than all other States, because of the seamless integration of the USC and NOAA databases and the use of the MOST model. They are a significant improvement over earlier map generations. As part of a continuous improvement in response, mitigation and planning and community education, the California inundation maps can contribute in reducing tsunami risk. References -Bardet, JP et al (2003), Landslide tsunamis: Recent findings and research directions, Pure and Applied Geophysics, 160, (10-11), 1793-1809. -Eisner, R., Borrero, C., Synolakis, C.E. (2001) Inundation Maps for the State of California, International Tsunami Symposium, ITS 2001 Proceedings, NHTMP Review Paper #4, 67-81. -Synolakis, C.E., D. McCarthy, V.V. Titov, J.C. Borrero, (1998) Evaluating the Tsunami Risk in California, CALIFORNIA AND THE WORLD OCEAN '97, 1225-1236, Proceedings ASCE, ISBN: 0-7844-0297-3.

Barberopoulou, Aggeliki; Borrero, Jose; Uslu, Burak; Kanoglu, Utku; Synolakis, Costas

2010-05-01

269

TIDE-TSUNAMI INTERACTIONS  

Directory of Open Access Journals (Sweden)

Full Text Available In this paper we investigate important dynamics defining tsunami enhancement in the coastal regions and related to interaction with tides. Observations and computations of the Indian Ocean Tsunami usually show amplifications of the tsunami in the near-shore regions due to water shoaling. Additionally, numerous observations depicted quite long ringing of tsunami oscillations in the coastal regions, suggesting either local resonance or the local trapping of the tsunami energy. In the real ocean, the short-period tsunami wave rides on the longer-period tides. The question is whether these two waves can be superposed linearly for the purpose of determining the resulting sea surface height (SSH or rather in the shallow water they interact nonlinearly, enhancing/reducing the total sea level and currents. Since the near–shore bathymetry is important for the run-up computation, Weisz and Winter (2005 demonstrated that the changes of depth caused by tides should not be neglected in tsunami run-up considerations. On the other hand, we hypothesize that much more significant effect of the tsunami-tide interaction should be observed through the tidal and tsunami currents. In order to test this hypothesis we apply a simple set of 1-D equations of motion and continuity to demonstrate the dynamics of tsunami and tide interaction in the vicinity of the shelf break for two coastal domains: shallow waters of an elongated inlet and narrow shelf typical for deep waters of the Gulf of Alaska.

Zygmunt Kowalik

2006-01-01

270

Tsunami Prediction and Earthquake Parameters Estimation in the Red Sea  

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.

Sawlan, Zaid A

2012-12-01

271

Event trees and dynamic event trees: Applications to steam generator tube rupture accidents  

International Nuclear Information System (INIS)

The dynamic event tree analysis method (DETAM) is a simulation based approach that models the integrated, dynamic response of the plant/operating crew system to an accident. It extends the conventional event tree/fault tree methodology for accident sequence analysis in two ways. First, it allows for tree branchings at discrete points in time. Second, the tree sequences explicitly track changes in the operating crew state, as well as changes in the plant hardware state. Process variable calculations and operating procedures are used in linking the crew and hardware behaviour. - The paper compares the conventional event tree/fault tree methodology for accident sequence analysis with the dynamic event tree method in the analysis of a pressurized water reactor steam generator tube rupture. Two previous PSA analyses are used for the comparison. The first employs the ''event tree with boundary conditions'' approach and uses fairly detailed top event headings. The second employs the ''linked fault tree'' approach and uses a relatively small event tree. - A quantitative comparison of the results of the three analyses shows that, in this particularly case study, the DETAM results appear to be less conservative. This is due, in part, to DETAM's treatment of recovery actions embedded in the emergency operating procedures. The quantitative results, however, should be viewed with some caution, since: (a) the three analyses have different scopes and employ different assumptions, and (b) a number of the parameters used in the DETAM analysis are highly uncertain. - A qualitative comparison of results shows that the dominant sequences predicted by each methodology are similar. However, the DETAM scenario descriptions are more detailed and allow better definition of steps to reduce risk. Further, the DETAM models deal with the variety of human error forms and their consequences; this provides a better capability of identifying and quantifying complex accident scenarios that may not be treated in conventional PSA models. (author). 8 refs, 3 figs, 1 tab

1991-06-03

272

Computational Particle Physics for Event Generators and Data Analysis  

CERN Document Server

High-energy physics data analysis relies heavily on the comparison between experimental and simulated data as stressed lately by the Higgs search at LHC and the recent identification of a Higgs-like new boson. The first link in the full simulation chain is the event generation both for background and for expected signals. Nowadays event generators are based on the automatic computation of matrix element or amplitude for each process of interest. Moreover, recent analysis techniques based on the matrix element likelihood method assign probabilities for every event to belong to any of a given set of possible processes. This method originally used for the top mass measurement, although computing intensive, has shown its power at LHC to extract the new boson signal from the background. Serving both needs, the automatic calculation of matrix element is therefore more than ever of prime importance for particle physics. Initiated in the eighties, the techniques have matured for the lowest order calculations (tree-le...

Perret-Gallix, Denis

2013-01-01

273

Tsunami Hazard Assessment: Source regions of concern to U.S. interests derived from NOAA Tsunami Forecast Model Development  

Science.gov (United States)

Synthetic tsunamis generated from source regions around the Pacific Basin are analyzed in terms of their relative impact on United States coastal locations.. The region of tsunami origin is as important as the expected magnitude and the predicted inundation for understanding tsunami hazard. The NOAA Center for Tsunami Research has developed high-resolution tsunami models capable of predicting tsunami arrival time and amplitude of waves at each location. These models have been used to conduct tsunami hazard assessments to assess maximum impact and tsunami inundation for use by local communities in education and evacuation map development. Hazard assessment studies conducted for Los Angeles, San Francisco, Crescent City, Hilo, and Apra Harbor are combined with results of tsunami forecast model development at each of seventy-five locations. Complete hazard assessment, identifies every possible tsunami variation from a pre-computed propagation database. Study results indicate that the Eastern Aleutian Islands and Alaska are the most likely regions to produce the largest impact on the West Coast of the United States, while the East Philippines and Mariana trench regions impact Apra Harbor, Guam. Hawaii appears to be impacted equally from South America, Alaska and the Kuril Islands.

Eble, M. C.; uslu, B. U.; Wright, L.

2013-12-01

274

Simulation systems for tsunami wave propagation forecasting within the French tsunami warning center  

Directory of Open Access Journals (Sweden)

Full Text Available A model-based tsunami prediction system has been developed as part of the French Tsunami Warning Center (operational since 1 July 2012. It involves a precomputed unit source functions database (i.e., a number of tsunami model runs that are calculated ahead of time and stored. For the Mediterranean basin, the faults of the unit functions are placed adjacent to each other, following the discretization of the main seismogenic faults. An automated composite scenarios calculation tool is implemented to allow the simulation of any tsunami propagation scenario (i.e., of any seismic moment. Uncertainty on the magnitude of the detected event and inaccuracy of the epicenter location are taken into account in the composite scenarios calculation. Together with this forecasting system, another operational tool based on real time computing is implemented as part of the French Tsunami Warning Center. This second tsunami simulation tool takes advantage of multiprocessor approaches and more realistic seismological parameters, once the focal mechanism is established. Three examples of historical earthquakes are presented, providing warning refinement compared to the rough tsunami risk map given by the model-based decision matrix.

A. Gailler

2013-10-01

275

Events analysis of the main generator using reliability block diagram  

International Nuclear Information System (INIS)

Generator failure events at overseas and Japanese nuclear power plants were analyzed in detail through a reliability block diagram. This analysis not only took note of the total number of component failure and part failures but also focused on age-related degradation phenomena. Components or parts that were found to have failed most frequently included stator cooling system pipes, stator cooling system valves, automatic voltage regulators, and alternating-current exciters. Event reports on these components or parts were reexamined one by one. Because these components or parts have been adequately inspected, it was confirmed that there are no additional maintenance measures that should be reflected in Japanese pressurized water reactor (PWR) power plants. A comparison of the frequency of failures between Japanese and American power plants revealed that Japanese power plants suffered approximately one-tenth of the frequency of failures experienced in American plants, suggesting that higher levels of maintenance work are achieved at Japanese plants. (author)

2006-10-01

276

Tool for Generating Realistic Residential Hot Water Event Schedules: Preprint  

Energy Technology Data Exchange (ETDEWEB)

The installed energy savings for advanced residential hot water systems can depend greatly on detailed occupant use patterns. Quantifying these patterns is essential for analyzing measures such as tankless water heaters, solar hot water systems with demand-side heat exchangers, distribution system improvements, and recirculation loops. This paper describes the development of an advanced spreadsheet tool that can generate a series of year-long hot water event schedules consistent with realistic probability distributions of start time, duration and flow rate variability, clustering, fixture assignment, vacation periods, and seasonality. This paper also presents the application of the hot water event schedules in the context of an integral-collector-storage solar water heating system in a moderate climate.

Hendron, B.; Burch, J.; Barker, G.

2010-08-01

277

Marin Tsunami (video)  

Science.gov (United States)

Tsunamis are a constant threat to the coasts of our world. Although tsunamis are infrequent along the West coast of the United States, it is possible and necessary to prepare for potential tsunami hazards to minimize loss of life and property. Community awareness programs are important, as they strive to create an informed society by providing education and training. The Marin coast could be struck by a tsunami. Whether you live in Marin County, visit the beaches, or rent or own a home near the coast, it is vital to understand the tsunami threat and take preparation seriously. Marin Tsunami tells the story of what several West Marin communities are doing to be prepared. This video was produced by the US Geological Survey (USGS) in cooperation with the Marin Office of Emergency Services.

Filmed and edited by: Loeffler, Kurt; Gesell, Justine

2010-01-01

278

Preliminary Probabilistic Tsunami Hazard Assessment of Canadian Coastlines  

Science.gov (United States)

We present a preliminary probabilistic tsunami hazard assessment of Canadian coastlines from local and far-field, earthquake and large landslide sources. Our multifaceted analysis is based on published historical, paleotsunami and paleoseismic data, modelling, and empirical relations between fault area, earthquake magnitude and tsunami runup. We consider geological sources with known tsunami impacts on Canadian coasts (e.g., Cascadia and other Pacific subduction zones; the 1755 Lisbon tsunami source; Atlantic continental slope failures) as well as potential sources with previously unknown impact (e.g., Explorer plate subduction; Caribbean subduction zones; crustal faults). The cumulative estimated tsunami hazard for potentially damaging runup (? 1.5 m) of the outer Canadian Pacific coastline is ~40-80% in 50 y, respectively one and two orders of magnitude greater than the outer Atlantic (~1-15%) and the Arctic (River delta requires further study. We highlight areas susceptible to locally-damaging landslide-generated tsunamis, but do not quantify the hazard.

Leonard, L. J.; Rogers, G. C.; Mazzotti, S.

2012-12-01

279

Assessment of the tsunami-induced current hazard  

Science.gov (United States)

occurrence of tsunami damage is not limited to events causing coastal inundation. Even without flooding, maritime assets are vulnerable to significant damage from strong currents and associated drag forces. While such impacts have been observed in the past, they have not been well studied in any context. Nearshore tsunami currents are governed by nonlinear and turbulent physics and often have large spatial and temporal variability making high-fidelity modeling particularly challenging. Furthermore, measured data for the validation of numerical simulations is limited, with few quality data sets appearing after recent tsunami events. In this paper, we present a systematic approach for the interpretation of measured tsunami-induced current impacts as well as a validation approach for simulation tools. The methods and results provided here lay the foundation for much needed efforts to assess tsunami hazards in ports and harbors.

Lynett, Patrick J.; Borrero, Jose; Son, Sangyoung; Wilson, Rick; Miller, Kevin

2014-03-01

280

2006: STATUS OF TSUNAMI SCIENCE RESEARCH AND FUTURE DIRECTIONS OF RESEARCH  

Directory of Open Access Journals (Sweden)

Full Text Available In 2005, Dr. Robert Wiegel compiled “Tsunami Information Sources”. The compilation has been made available via a website and has been published as an issue in Science of Tsunami Hazards. The compiled references have been assigned keyword descriptions, and compiled in order to review the breath and depth of Tsunami Science publications.The review indicates that tsunami research involves eight major scientific disciplines: Geology, Seismology, Tsunami Science, Engineering, Disaster Management, Meteorology and Communications. These disciplines were subdivided into many topical subjects and the results were tabulated.The topics having the largest number of publications include: tsunamigenic earthquakes, numerical modeling, field surveys, engineering models, harbor, bay, and canal modeling and observations, energy of tsunamis, workshops, tsunami warning centers, instrumentation, tsunami catalogs, tsunami disaster mitigation, evaluation of hazards, the aftermath of tsunamis on humans, and AID provided to Tsunami Damaged Communities.Several areas of research were identified as likely directions for future research, including: paleotsunami studies, risk assessments, instrumentation, numerical modeling of earthquakes and tsunami, particularly the 2004 Indian Ocean event. There is a dearth of recent publications available on tsunami hazards education for the general public.

Barbara H. Keating

2006-01-01

 
 
 
 
281

Computational particle physics for event generators and data analysis  

Science.gov (United States)

High-energy physics data analysis relies heavily on the comparison between experimental and simulated data as stressed lately by the Higgs search at LHC and the recent identification of a Higgs-like new boson. The first link in the full simulation chain is the event generation both for background and for expected signals. Nowadays event generators are based on the automatic computation of matrix element or amplitude for each process of interest. Moreover, recent analysis techniques based on the matrix element likelihood method assign probabilities for every event to belong to any of a given set of possible processes. This method originally used for the top mass measurement, although computing intensive, has shown its efficiency at LHC to extract the new boson signal from the background. Serving both needs, the automatic calculation of matrix element is therefore more than ever of prime importance for particle physics. Initiated in the 80's, the techniques have matured for the lowest order calculations (tree-level), but become complex and CPU time consuming when higher order calculations involving loop diagrams are necessary like for QCD processes at LHC. New calculation techniques for next-to-leading order (NLO) have surfaced making possible the generation of processes with many final state particles (up to 6). If NLO calculations are in many cases under control, although not yet fully automatic, even higher precision calculations involving processes at 2-loops or more remain a big challenge. After a short introduction to particle physics and to the related theoretical framework, we will review some of the computing techniques that have been developed to make these calculations automatic. The main available packages and some of the most important applications for simulation and data analysis, in particular at LHC will also be summarized (see CCP2012 slides [1]).

Perret-Gallix, Denis

2013-08-01

282

New Edition of the UNESCO-IOC International Tsunami Survey Team (ITST) Post-Tsunami Survey Field Guide  

Science.gov (United States)

A subcommittee of the IUGG International Tsunami Commission was convened in 2010 to revise and update the 1998 UNESCO-IOC Post-Tsunami Survey Field Guide. The revised Guide addresses the developments in the tsunami field since 1998, the need to accommodate vastly increased amounts of data, and to incorporate disciplines that were not covered in the original guide. The Guide also advocates a systems-approach to assessing tsunami impacts that examines the full range of physical, environmental, and socio-economic effects and their interrelationship, bringing tsunami research efforts into a closer alignment with the UN International Strategy for Disaster Reduction (UNISDR). This Field Guide is intended to provide a flexible framework to facilitate the acquisition of critical data in the immediate aftermath of significant tsunamis and to balance the needs of international researchers with those of communities and agencies involved with response and recovery. It will be of use to a variety of people and organizations who may either participate in, assist in coordination, or host post-tsunami field surveys. It is hoped that this Guide will promote pre-event planning in countries at risk of tsunamis to reduce the stresses of developing organizational logistics in the post-emergency response phase and make the process of conducting an ITST easier and more productive for both participating researchers and host country organizations. A complete draft of the Guide will be presented at the meeting and members of the tsunami community invited to comment.

Dengler, L.; Dominey-Howes, D.; Yamamoto, M.; Borrero, J. C.; Dunbar, P. K.; Fritz, H. M.; Imamura, F.; Kong, L. S.; Koshimura, S.; McAdoo, B. G.; Satake, K.; Yalciner, A. C.; Yulianto, E.

2011-12-01

283

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)

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 simple earthquake sources of different magnitudes and located in the "vicinity" of the virtual scenario earthquake. In the DSS perspective, the members of the MSDB have to be suitably combined based on the information coming from the sensor networks, and the results are used during the crisis evolution phase to forecast the degree of exposition of different coastal areas. We provide examples from both databases whose members are computed by means of the in-house software called UBO-TSUFD, implementing the non-linear shallow-water equations and solving them over a set of nested grids that guarantee a suitable spatial resolution (few tens of meters) in specific, suitably chosen, coastal areas.

Armigliato, Alberto; Pagnoni, Gianluca; Zaniboni, Filippo; Tinti, Stefano

2013-04-01

284

Potential inundation of Lisbon downtown by a 1755-like tsunami  

Directory of Open Access Journals (Sweden)

Full Text Available In this study, we present 10 m resolution tsunami flooding maps for Lisbon downtown and the Tagus estuary. To compute these maps we use the present bathymetry and topographic maps and a reasonable estimate for the maximum credible tsunami scenario. Tsunami modeling was made with a non-linear shallow water model using four levels of nested grids. The tsunami flood is discussed in terms of flow depth, run-up height and maximum inundation area. The results show that, even today, in spite of the significant morphologic changes in the city river front after the 1755 earthquake, a similar event would cause tsunami flow depths larger than one meter in a large area along the Tagus estuary and Lisbon downtown. Other areas along the estuary with a high population density would also be strongly affected. The impact of the tide on the extent of tsunami inundation is discussed, due to the large amplitude range of the tide in Lisbon, and compared with the historical descriptions of the 1755 event. The results presented here can be used to identify the potential tsunami inundation areas in Lisbon; this identification comprises a key element of the Portuguese tsunami emergency management system.

M. A. Baptista

2011-12-01

285

The Solomon Islands Tsunami of 6 February 2013 in the Santa Cruz Islands: Field Survey and Modeling  

Science.gov (United States)

On February 6, 2013 at 01:12:27 UTC (local time: UTC+11), a magnitude Mw 8.0 earthquake occurred 70 km to the west of Ndendo Island (Santa Cruz Island) in the Solomon Islands. The under-thrusting earthquake near a 90° bend, where the Australian plate subducts beneath the Pacific plate generated a locally focused tsunami in the Coral Sea and the South Pacific Ocean. The tsunami claimed the lives of 10 people and injured 15, destroyed 588 houses and partially damaged 478 houses, affecting 4,509 people in 1,066 households corresponding to an estimated 37% of the population of Santa Cruz Island. A multi-disciplinary international tsunami survey team (ITST) was deployed within days of the event to document flow depths, runup heights, inundation distances, sediment and coral boulder depositions, land level changes, damage patterns at various scales, performance of the man-made infrastructure and impact on the natural environment. The 19 to 23 February 2013 ITST covered 30 locations on 4 Islands: Ndendo (Santa Cruz), Tomotu Noi (Lord Howe), Nea Tomotu (Trevanion, Malo) and Tinakula. The reconnaissance completely circling Ndendo and Tinakula logged 240 km by small boat and additionally covered 20 km of Ndendo's hard hit western coastline by vehicle. The collected survey data includes more than 80 tsunami runup and flow depth measurements. The tsunami impact peaked at Manoputi on Ndendo's densely populated west coast with maximum tsunami height exceeding 11 m and local flow depths above ground exceeding 7 m. A fast tide-like positive amplitude of 1 m was recorded at Lata wharf inside Graciosa Bay on Ndendo Island and misleadingly reported in the media as representative tsunami height. The stark contrast between the field observations on exposed coastlines and the Lata tide gauge recording highlights the importance of rapid tsunami reconnaissance surveys. Inundation distance and damage more than 500 m inland were recorded at Lata airport on Ndendo Island. Landslides were observed on volcanic Tinakula Island and on Ndendo Island. Observations from the 2013 Santa Cruz tsunami are compared against the 2007 and 2010 Solomon Islands tsunamis. The field observations in the Santa Cruz Islands present an important dataset to assess tsunami impact in the near-source region. The tsunami was also recorded at deep-ocean tsunameters and tide gauges throughout the Pacific. These observations allow us to further investigate the physics of tsunami generation caused by the seismic process (or other non-seismic mechanisms). We use numerical model MOST to analyze the large runup and complex impact distribution caused by the Santa Cruz tsunami. Source models obtained using seismic data / tsunami data are carried out to initialize the tsunami model. MOST uses two sets of numerical grids to investigate both the near- and far-field aspects of the tsunami. The basin-scale modeling results are computed using a spatial resolution of 4 arc min (approx. 7,200 m) and compared with measurements at deep-ocean tsunameters. The near-field modeling is carried out using a series of telescoped grids up to a grid resolution of tens of meters to compare with the tsunami runup and flooding extent obtained through the field survey in the Solomon Islands. The modeling results emphasize the contrast between the tsunami impact on the exposed coastline and the sheltered Lata Bay stressing the problematic interpretation of a tsunami in progress based solely on near-source tide-gauge measurements. The team also interviewed eyewitnesses and educated residents about the tsunami hazard in numerous ad hoc presentations and discussions. The combination of ancestral knowledge and recent Solomon Islands wide geohazards education programs triggered an immediate spontaneous self-evacuation containing the death toll in the small evacuation window of few minutes between the end of the ground shaking and the onslaught of the tsunami. Fortunately school children were shown a video on the 1 April 2007 Solomon Islands tsunami 3 months prior to the Santa Cruz event and the headmaster of the

Fritz, Hermann M.; Papantoniou, Antonios; Biukoto, Litea; Albert, Gilly; Wei, Yong

2014-05-01

286

A Walk through TRIDEC's intermediate Tsunami Early Warning System  

Science.gov (United States)

The management of natural crises is an important application field of the technology developed in the project Collaborative, Complex, and Critical Decision-Support in Evolving Crises (TRIDEC), co-funded by the European Commission in its Seventh Framework Programme. TRIDEC is based on the development of the German Indonesian Tsunami Early Warning System (GITEWS) and the Distant Early Warning System (DEWS) providing a service platform for both sensor integration and warning dissemination. In TRIDEC new developments in Information and Communication Technology (ICT) are used to extend the existing platform realising a component-based technology framework for building distributed tsunami warning systems for deployment, e.g. in the North-eastern Atlantic, the Mediterranean and Connected Seas (NEAM) region. The TRIDEC system will be implemented in three phases, each with a demonstrator. Successively, the demonstrators are addressing challenges, such as the design and implementation of a robust and scalable service infrastructure supporting the integration and utilisation of existing resources with accelerated generation of large volumes of data. These include sensor systems, geo-information repositories, simulation tools and data fusion tools. In addition to conventional sensors also unconventional sensors and sensor networks play an important role in TRIDEC. The system version presented is based on service-oriented architecture (SOA) concepts and on relevant standards of the Open Geospatial Consortium (OGC), the World Wide Web Consortium (W3C) and the Organization for the Advancement of Structured Information Standards (OASIS). In this way the system continuously gathers, processes and displays events and data coming from open sensor platforms to enable operators to quickly decide whether an early warning is necessary and to send personalized warning messages to the authorities and the population at large through a wide range of communication channels. The system integrates OGC Sensor Web Enablement (SWE) compliant sensor systems for the rapid detection of hazardous events, like earthquakes, sea level anomalies, ocean floor occurrences, and ground displacements. Using OGC Web Map Service (WMS) and Web Feature Service (WFS) spatial data are utilized to depict the situation picture. The integration of a simulation system to identify affected areas is considered using the OGC Web Processing Service (WPS). Warning messages are compiled and transmitted in the OASIS Common Alerting Protocol (CAP) together with addressing information defined via the OASIS Emergency Data Exchange Language - Distribution Element (EDXL-DE). The first system demonstrator has been designed and implemented to support plausible scenarios demonstrating the treatment of simulated tsunami threats with an essential subset of a National Tsunami Warning Centre (NTWC). The feasibility and the potentials of the implemented approach are demonstrated covering standard operations as well as tsunami detection and alerting functions. The demonstrator presented addresses information management and decision-support processes in a hypothetical natural crisis situation caused by a tsunami in the Eastern Mediterranean. Developments of the system are based to the largest extent on free and open source software (FOSS) components and industry standards. Emphasis has been and will be made on leveraging open source technologies that support mature system architecture models wherever appropriate. All open source software produced is foreseen to be published on a publicly available software repository thus allowing others to reuse results achieved and enabling further development and collaboration with a wide community including scientists, developers, users and stakeholders. This live demonstration is linked with the talk "TRIDEC Natural Crisis Management Demonstrator for Tsunamis" (EGU2012-7275) given in the session "Architecture of Future Tsunami Warning Systems" (NH5.7/ESSI1.7).

Hammitzsch, M.; Reißland, S.; Lendholt, M.

2012-04-01

287

Quantification of Monte Carlo event generator scale-uncertainties with an example ATLAS analysis studying underlying event properties  

Energy Technology Data Exchange (ETDEWEB)

Monte Carlo (MC) event generators are widely employed in the analysis of experimental data also for LHC in order to predict the features of observables and test analyses with them. These generators rely on phenomenological models containing various parameters which are free in certain ranges. Variations of these parameters relative to their default lead to uncertainties on the predictions of the event generators and, in turn, on the results of any experimental data analysis making use of the event generator. A Generalized method for quantifying a certain class of these generator based uncertainties will be presented in this talk. We study for the SHERPA event generator the effect on the analysis results from uncertainties in the choice of the merging and factorization scale. The quantification is done within an example ATLAS analysis measuring underlying event UE properties in Z-boson production limited to low transverse momenta (p{sub T}{sup Z}<3 GeV) of the Z-boson. The analysis extracts event-shape distributions from charged particles in the event that do not belong to the Z decay for generate Monte Carlo event and data which are unfolded back to the generator level.

Brandt, Gerhard [University of Oxford (United Kingdom); Krauss, Frank [IPPP Durham (United Kingdom); Lacker, Heiko; Leyton, Michael; Mamach, Martin; Schulz, Holger; Weyh, Daniel [Humboldt University of Berlin (Germany)

2012-07-01

288

Quantification of Monte Carlo event generator scale-uncertainties with an example ATLAS analysis studying underlying event properties  

International Nuclear Information System (INIS)

Monte Carlo (MC) event generators are widely employed in the analysis of experimental data also for LHC in order to predict the features of observables and test analyses with them. These generators rely on phenomenological models containing various parameters which are free in certain ranges. Variations of these parameters relative to their default lead to uncertainties on the predictions of the event generators and, in turn, on the results of any experimental data analysis making use of the event generator. A Generalized method for quantifying a certain class of these generator based uncertainties will be presented in this talk. We study for the SHERPA event generator the effect on the analysis results from uncertainties in the choice of the merging and factorization scale. The quantification is done within an example ATLAS analysis measuring underlying event UE properties in Z-boson production limited to low transverse momenta (pTZ<3 GeV) of the Z-boson. The analysis extracts event-shape distributions from charged particles in the event that do not belong to the Z decay for generate Monte Carlo event and data which are unfolded back to the generator level.

2012-03-02

289

GPS water level measurements for Indonesia's Tsunami Early Warning System  

Directory of Open Access Journals (Sweden)

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.

T. Schöne

2011-03-01

290

Chicxulub Tsunami Animation  

Science.gov (United States)

An animation that simulates the tsunami created by the Chicxulub impact off the coast of Mexico. The model simulates the height of the tsunami waves as they reached the surrounding parts of North, Central, South America as they are projected to have looked at the time of the impact.

Ward, Steven N.; Cruz, University O.

291

Sedimentological Evidence of the 1812 Santa Barbara Tsunami in Carpinteria Marsh, CA  

Science.gov (United States)

The Santa Barbara coast is at risk for tsunamis generated from tectonic movement in areas of compression and extension associated with the San Andreas Fault, as well as from submarine landslide movement in the Santa Barbara channel. Historical documents and other records indicate Santa Barbara has experienced approximately sixteen historical tsunamis, the largest of which may have occurred on Dec 21, 1812, following a magnitude ~7.1 earthquake. We propose that an anomalous sand deposit, Sand Facies One (SF1), which is found within the first meter of sediment throughout Carpinteria Marsh in Carpinteria, CA, may represent deposition related to this event. We have collected 23 vibracores, up to 4.1 m in length, and three Geoprobe cores to ~14 m depth in Carpinteria Marsh. SF1 occurs in 20 of the 23 vibracores and exhibits sedimentological characteristics associated with a tsunami genesis such as: fining upward grain size, sharp or erosional basal contact, and thinning of the deposit landward. Mineralogy, deposit geometry, and X-Ray Florescence (XRF) data are used to determine a marine versus terrestrial origin for the layer. It is difficult, however, to differentiate between storm and tsunami deposits based purely on the sedimentary characteristics of a deposit. We show that an improved age chronology which includes exotic pollen stratigraphy and radiocarbon data indicates an age range appropriate for the 1812 event but does not exclude regional flooding events documented in the 1860s. We use the characteristics of SF1 to determine if similar layers occur at other depths in the Geoprobe cores. Preliminary core descriptions indicate that there is at least one layer which exhibits characteristics similar to SF1and may indicate the occurrence of a similar inundation event. We conclude that tsunami deposition related to the 1812 event is a possible explanation for SF1, but additional analyses are needed to rule out other flooding events. Whether storm or tsunami, the deposit's characteristics imply inundation at a scale and intensity that would be detrimental to the low lying areas of the Santa Barbara coast--the presence of similar layers at greater depths imply this degree of inundation has recurred over time and is an important process to understand for risk assessment for the Santa Barbara coast.

Reynolds, L.; Simms, A.; King, B. L.; Rockwell, T. K.; Ejarque, A.; Anderson, R.; Peters, R. B.

2013-12-01

292

Next-Generation Navigational Infrastructure and the ATLAS Event Store  

CERN Document Server

The ATLAS event store employs a persistence framework with extensive navigational capabilities. These include real-time back navigation to upstream processing stages, externalizable data object references, navigation from any data object to any other both within a single file and across files, and more. The 2013-2014 shutdown of the Large Hadron Collider provides an opportunity to enhance this infrastructure in several ways that both extend these capabilities and allow the collaboration to better exploit emerging computing platforms. Enhancements include redesign with efficient file merging in mind, content-based indices in optimized reference types, and support for forward references. The latter provide the potential to construct valid references to data before those data are written, a capability that is useful in a variety of multithreading, multiprocessing, distributed processing, and deferred processing scenarios. This paper describes the architecture and design of the next generation of ATLAS navigation...

van Gemmeren, P; The ATLAS collaboration; Nowak, M

2013-01-01

293

Numerical tsunami simulation including elastic loading and seawater density stratification  

Science.gov (United States)

Systemic discrepancies between observed and modeled tsunami wave speeds were previously identified for two recent major tsunamis: the 2010 Maule and 2011 Tohoku events. To account for these discrepancies, we developed a numerical tsunami propagation code solving the shallow water equation and including the effects of elastic loading of the seafloor by the tsunami as well as a linear density profile in the seawater column. We show here that both effects are important to explain the commonly observed difference between observations and simulations. We conclude that the density variation in the seawater column affects the wave speed without changing the waveform, whereas the loading effect has an effect on the wave speed and the waveform showing a negative phase before the main arrival due to the depression of the seafloor surrounding the tsunami wave. The combination of both effects is needed to achieve a better match between observations and simulations.

Allgeyer, Sébastien; Cummins, Phil

2014-04-01

294

THE TSUNAMI ASSESSMENT MODELLING SYSTEM BY THE JOINT RESEARCH CENTRE  

Directory of Open Access Journals (Sweden)

Full Text Available The Tsunami Assessment Modeling System was developed by the European Commission, Joint Research Centre, in order to serve Tsunami early warning systems such as the Global Disaster Alerts and Coordination System (GDACS in the evaluation of possible consequences by a Tsunami of seismic nature. The Tsunami Assessment Modeling System is currently operational and is calculating in real time all the events occurring in the world, calculating the expected Tsunami wave height and identifying the locations where the wave height should be too high. The first part of the paper describes the structure of the system, the underlying analytical models and the informatics arrangement; the second part shows the activation of the system and the results of the calculated analyses. The final part shows future development of this modeling tool.

Alessandro Annunziato

2007-01-01

295

Interfacing GoSam with Monte Carlo Event Generators  

CERN Document Server

In this talk the most recent results obtained by interfacing GoSam with external Monte Carlo event generators are presented and summarized. In the last year the automatic one-loop amplitude generator GoSam has been used for the computation of several processes relevant for the LHC physics program. In the first part of the talk the latest results are summarized and the status of the interfaces to several external Monte Carlo programs, based on the Binoth-Les-Houches-Accord, is reported. The second part is dedicated to two selected computations. One concerning the associated production of a Higgs and a vector boson in association with 0 and 1 jet computed with GoSam+Powheg, and one focusing on the analysis of the forward-backward asymmetry in the production of top quark pairs using 0 and 1 jet merged samples with GoSam+Sherpa. Finally some recent results on Beyond-Standard-Model physics are also presented.

Luisoni, Gionata

2013-01-01

296

Foam A General Purpose Cellular Monte Carlo Event Generator  

CERN Multimedia

A general purpose, self-adapting, Monte Carlo (MC) event generator (simulator) is described. The high efficiency of the MC, that is small maximum weight or variance of the MC weight is achieved by means of dividing the integration domain into small cells. The cells can be $n$-dimensional simplices, hyperrectangles or Cartesian product of them. The grid of cells, called ``foam'', is produced in the process of the binary split of the cells. The choice of the next cell to be divided and the position/direction of the division hyper-plane is driven by the algorithm which optimizes the ratio of the maximum weight to the average weight or (optionally) the total variance. The algorithm is able to deal, in principle, with an arbitrary pattern of the singularities in the distribution. As any MC generator, it can also be used for the MC integration. With the typical personal computer CPU, the program is able to perform adaptive integration/simulation at relatively small number of dimensions ($\\leq 16$). With the continu...

Jadach, Stanislaw

2003-01-01

297

Test of TEDA (Tsunami Early Detection Algorithm) on the 11 March 2011 Tohoku tsunami marigrams  

Science.gov (United States)

The records of the 11 March 2011 Tohoku tsunami have been used to test TEDA, a Tsunami Early Detection Algorithm (Bressan and Tinti, 2011) that aims to detect tsunamis and potentially dangerous long period oscillations on sea level data. TEDA is composed of two parallel detection algorithms: the tsunami detection algorithm is built on the detided slope of the sea-level signal and it triggers a detection based on a dynamic threshold that varies according to the level of the previous background signal, while the secure detection activates an alert according to a filtered sea-level amplitude threshold. Both modules are designed to work at a station level after being calibrated for the station's site, i.e. their performance should be optimized to the local typical background by carefully setting the temporal parameters that define TEDA functions and the thresholds that define the detection. In this work the performance of TEDA has first been evaluated by testing TEDA with the calibration found best for Adak, USA, on 123 tsunami records from the 11 March 2011 Tohoku event located along the coasts around the Pacific Ocean, characterized by different background oscillations and tsunami response. The main goal was to evaluate the efficiency of TEDA and to assess whether a particular calibration could have a general validity for different situations. To further check the sensitivity of TEDA, additional tests have been performed by slightly increasing and decreasing the threshold for detection. The results are positive and show that TEDA is able to detect the majority of the tsunami signals in a robust way and therefore it could be used within a Tsunami Warning System.

Bressan, L.; Tinti, S.

2012-04-01

298

TRIDEC Natural Crisis Management Demonstrator for Tsunamis  

Science.gov (United States)

The management of natural crises is an important application field of the technology developed in the project Collaborative, Complex, and Critical Decision-Support in Evolving Crises (TRIDEC), co-funded by the European Commission in its Seventh Framework Programme. TRIDEC is based on the development of the German Indonesian Tsunami Early Warning System (GITEWS) and the Distant Early Warning System (DEWS) providing a service platform for both sensor integration and warning dissemination. In TRIDEC new developments in Information and Communication Technology (ICT) are used to extend the existing platform realising a component-based technology framework for building distributed tsunami warning systems for deployment, e.g. in the North-eastern Atlantic, the Mediterranean and Connected Seas (NEAM) region. The Kandilli Observatory and Earthquake Research Institute (KOERI), representing the Tsunami National Contact (TNC) and Tsunami Warning Focal Point (TWFP) for Turkey, is one of the key partners in TRIDEC. KOERI is responsible for the operation of a National Tsunami Warning Centre (NTWC) for Turkey and establishes Candidate Tsunami Watch Provider (CTWP) responsibilities for the NEAM region. Based on this profound experience, KOERI is contributing valuable requirements to the overall TRIDEC system and is responsible for the definition and development of feasible tsunami-related scenarios. However, KOERI's most important input focuses on testing and evaluating the TRIDEC system according to specified evaluation and validation criteria. The TRIDEC system will be implemented in three phases, each with a demonstrator. Successively, the demonstrators are addressing challenges, such as the design and implementation of a robust and scalable service infrastructure supporting the integration and utilisation of existing resources with accelerated generation of large volumes of data. These include sensor systems, geo-information repositories, simulation tools and data fusion tools. In addition to conventional sensors also unconventional sensors and sensor networks play an important role in TRIDEC. The first system demonstrator, deployed at KOERI's crisis management room, has been designed and implemented to support plausible scenarios for the Turkish NTWC and to demonstrate the treatment of simulated tsunami threats with an essential subset of a NTWC. The feasibility and the potentials of the implemented approach are demonstrated covering standard operations as well as tsunami detection and alerting functions. The demonstrator presented addresses information management and decision-support processes in a hypothetical natural crisis situation caused by a tsunami in the Eastern Mediterranean.

Hammitzsch, M.; Necmioglu, O.; Reißland, S.; Lendholt, M.; Comoglu, M.; Ozel, N. M.; Wächter, J.

2012-04-01

299

Broadband Analysis of the Energetics of Earthquakes and Tsunamis in the Sunda Forearc from 1987-2012  

Science.gov (United States)

In the eighteen years before the 2004 Sumatra Mw 9.1 earthquake, the forearc off Sumatra experienced only one large (Mw > 7.0) thrust event and experienced no earthquakes that generated measurable tsunami wave heights. In the subsequent eight years, twelve large thrust earthquakes occurred of which half generated measurable tsunamis. The number of broadband earthquakes (those events with Mw > 5.5 for which broadband teleseismic waveforms have sufficient signal to compute depths, focal mechanisms, moments and radiated energies) jumped six fold after 2004. The progression of tsunami earthquakes, as well as the profuse increase in broadband activity, strongly suggests regional stress adjustments following the Sumatra 2004 megathrust earthquake. Broadband source parameters, published routinely in the Source Parameters (SOPAR) database of the USGS's NEIC (National Earthquake Information Center), have provided the most accurate depths and locations of big earthquakes since the implementation of modern digital seismographic networks. Moreover, radiated energy and seismic moment (also found in SOPAR) are related to apparent stress which is a measure of fault maturity. In mapping apparent stress as a function of depth and focal mechanism, we find that about 12% of broadband thrust earthquakes in the subduction zone are unequivocally above or below the slab interface. Apparent stresses of upper-plate events are associated with failure on mature splay faults, some of which generated measurable tsunamis. One unconventional source for local wave heights was a large intraslab earthquake. High-energy upper-plate events, which are dominant in the Aceh Basin, are associated with immature faults, which may explain why the region was bypassed by significant rupture during the 2004 Sumatra earthquake. The majority of broadband earthquakes are non-randomly concentrated under the outer-arc high. They appear to delineate the periphery of the contiguous rupture zones of large earthquakes. A not uncommon occurrence at the outer-arc high is that of a large (Mw >7.0) earthquake followed by another event, also of large magnitude, in very close spatial (<50 km) proximity within a short time (days to months). The physical separation between these events provides constraints on the nature of barriers to rupture propagation. Some of the glaring disparities in seismic damage and tsunami excitation for earthquakes with the same magnitude can be attributed to differences between rupture properties landward and seaward of the outer-arc high. Although most of the studied broadband earthquakes occurred in the wake of the Sumatra 2004 megathrust event, they illuminate tectonic features that exert a strong influence on rupture growth and extent. The application of broadband analysis to other island arcs will complement current criteria for evaluating seismic and tsunami potential

Choy, G. L.; Kirby, S. H.; Hayes, G. P.

2013-12-01

300

SEVERAL TSUNAMI SCENARIOS AT THE NORTH SEA AND THEIR CONSEQUENCES AT THE GERMAN BIGHT  

Directory of Open Access Journals (Sweden)

Full Text Available Tsunamis occurred in the past at the North Sea, but not frequently. There are historical and geological records of several tsunamis: the Storegga tsunami caused sediment deposits in Scotland 8,000 years ago and records of at least six earthquake-generated tsunamis exist from 842 to 1761 AC. The highest tsunami height witnessed at the German Bight is comparable to the maximum storm surge recorded and could thus cause similar or higher damage. However, there is little research on tsunami modeling in the North Sea. Here, we performed ten numerical experiments imposing N-waves at the open boundaries of a North Sea model system to study the potential consequences of tsunamis for the German Bight. One of the experiments simulated the second Storegga slide tsunami, seven more explored the influence of the incidence direction of the tsunami when entering the North Sea domain, and the other two explored the influence of tides on tsunami heights. We found that the German Bight is not exempt from tsunami risk. The main impact was from waves entering the North Sea from the north, even for tsunamis with sources south of the North Sea. Waves entering from the English Channel were attenuated after crossing the Dover strait. For some scenarios, the tsunami energy got focused directly at the Frisian Islands. The tidal phase had a strong influence on tsunami heights, although in this study the highest heights were obtained in the absence of tides. The duration of tsunamis is significantly smaller than that of storm surges, even though their flow velocities were found to be comparable or larger, thus increasing their possible damage. Therefore, tsunamis should not be dismissed as a threat at the North Sea basin and particularly at the German Bight.

Silvia Chacón-Barrantes

2013-01-01

 
 
 
 
301

A~probabilistic tsunami hazard assessment for Indonesia  

Science.gov (United States)

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.

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

302

A~probabilistic tsunami hazard assessment for Indonesia  

Directory of Open Access Journals (Sweden)

Full Text Available 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.

N. Horspool

2014-05-01

303

Simulations of Tsunami Hazard from Regional Sources in the South China and Adjoining Seas  

Science.gov (United States)

We examine the tsunami potential from sources located in the South China Sea and its adjoining basins, the Sulu and Sulawezi Seas, by running simulations using the MOST code for a number of scenarios of possible earthquakes at the various local subduction zones. In the Sulawezi Sea, we consider the events of 1918 at the Mindanao subduction zone, and 1996 at the Northern end of the Makassar Strait. In the Sulu Sea, we consider a scenario inspired by the 1948 Panay earthquake (because of the fractured nature of the plate system in those areas, it is not feasible to consider much larger earthquakes). In all three cases, we find that the tsunami is contained within the relevant marginal sea and does not penetrate significantly the greater South China Basin, but could cause significant damage to the Eastern coast of Borneo. Farther North, we consider as worst case scenarios events reaching 10**29 dyn*cm with rupture lengths of 400 km, both off Luzon Island and, under a slightly different geometry, off the Luzon Straits separating the Philippines and Taiwan. Such scenarios carry very significant hazard to all coastlines bordering the South China Sea, including Indochina and Borneo. We will also present models of landslide-generated tsunamis, inspired from the event of 14 February 1934 off the Luzon Strait, and the presumably Holocene Brunei mega-slide.

Kalligeris, N.; Synolakis, C. E.; Okal, E. A.

2008-12-01

304

Re-evaluation of Probable Maximum Tsunamis for Korean Nuclear Power Plant Sites  

Science.gov (United States)

Most of tsunami-triggering earthquakes occur in subduction zones around the Pacific Ocean area including the East Sea surrounded by Korea, Japan and Russia. In the East Sea, there were three major historical tsunami events occurred in 1964, 1983 and 1993. Among them, the Central East Sea Tsunami occurred in 1983, in special, caused huge losses of human lives and property damage at Korean coastal communities. There are several nuclear power plants under operation and several more plants will be built along the eastern coast of the Korean Peninsula. These historical tsunamis were considered individually to evaluate the probable maximum tsunamis for Korean nuclear power plant sites. Recently, several catastrophic tsunamis have been occurred around the Pacific Ocean rim. Among them, the East Japan Tsunami occurred on March 11, 2011 has attracted social attention due to the accident at Fukushima Dai-ichi nuclear power plant site. The accident is still going on. Therefore, new approach to evaluate the probable maximum tsunamis for the Korean sites is investigated in this study. Joint rupture of historical tsunami sources and hypothetical tsunami sources is employed to define the new source parameters of the probable maximum tsunami. The hypothetical tsunamis are inferred from the seismic gap theories. The numerical model using the modified leap-frog finite difference scheme is used to simulate the propagation of the new probable maximum tsunami across the East Sea and the numerical model simulating the associated run-up process of tsunamis is then employed to estimate the maximum run-up heights. Predicted results will be used to make a measure against unexpected tsunami attacks.

Jin, Sobeom; Hyun, Seung Gyu; Park, Sang ho; Bae, Jae Seok; Cho, Yong-Sik; Yoon, Sung Bum

2014-05-01

305

Tsunami Travel Time Approximation  

Science.gov (United States)

Eric Grosfils, Pomona College Summary Students are asked to calculate approximate tsunami travel times across the Pacific basin. The assignment builds off of a lab introducing students to Spatial Analyst, and ...

Grosfils, Eric

306

Tsunami-induced groundwater salinization in southeastern India  

Science.gov (United States)

On 26 December 2004, a northern Indonesia earthquake generated a tsunami that devastated coastal Indian Ocean regions. The impact of the tsunami on groundwater quality was unexpected as inundation and retreat of the tsunami wave lasted just 5 min. We report data showing salinization of the regionally extensive "Dune aquifer" in southeastern India. We present evidence that tsunami inundation resulted in contamination of groundwater supplies by locally raising salinity from potable levels up to 13,000 ?S/cm, which is approximately one quarter the salinity of seawater. Peak salinity occurred within 1 month as the saline water infiltrated. Salinization persisted for more than 10 months in the contaminated coastal region delimited by half of the run-up distance of the tsunami. Then, during the subsequent monsoon season, a second salinity peak was recorded. The timing and extent of natural attenuation of the saline groundwater is greatly influenced by recharge occurring from semiannual monsoons. Given the tsunami damage, our results highlight the fragile nature of water resources in this subsistence-level environment, which is densely populated within 500 m of the coast. We suggest guidelines for future protection of vulnerable coastal groundwater resources based on the tsunami experience. India has at least 750 km of coast bordered by the sand-dune aquifer that was flooded by the tsunami.

Violette, Sophie; Boulicot, Gilles; Gorelick, Steven M.

2009-04-01

307

Historical Tsunami Deposits on the Sanriku Coast, Japan  

Science.gov (United States)

At least six layers of tsunami deposit during the recent 500 years were found in a small valley on the Sanriku coast, just north of Taro (Miyako city, Iwate prefecture), where the 2011 tsunami heights from the Tohoku earthquake ranged from 17 to 34 m. The Sanriku coast is a Ria coast characterized by sawtooth-shaped coastline. Because of the steep-sloped valleys, alluvial deposits are very limited and tsunami traces are difficult to be preserved. Around the survey site, however, a marsh is separated from open sea by a beach ridge with the maximum altitude of about 4.5 m above mean sea level. In the marsh, well-decomposed peat has been developed. The sand deposits were brought by large tsunamis over the beach ridge and preserved in the marsh peat. We conducted drilling survey using the 3-m long Geo-slicer, trench survey, and outcrop observations. We sketch the sedimentary structure, conduct grain size analysis, reconstruct paleo-environment from microfossils, estimate the deposition age on the basis of radiocarbon dating and 210Pb/137Cs analysis, and correlate them with historical tsunamis. The uppermost sand layer which covers the ground surface is probably due to the 2011 tsunami. At least six event deposit layers can be identified in Geo-slicer's sample. Some sandy layers show normal or inverse grading structures and/or lamination, indicating a strong water flow. Some sand layers can be traced up to 400 m inland from the coast, while others can be identified only near the coast. The sandy layers well correlate with abrupt increases in marine microfossils floating near the sea surface. We use it as indicators of inflow of sea water into the marsh. The bottom peat layer of Geo-slicer's sample shows the AD 15th century, indicating that all the sand layers are from tsunamis in historical age during the recent 500 years. These tsunami deposits can be correlated with local tsunamis or distant tsunamis on the basis of radiocarbon dating and 210Pb/137Cs analysis. According to Japanese historical documents, candidates of tsunamis are from the 2011 Tohoku earthquake, the 1933 and 1896 Sanriku earthquakes, the 1793 Miyagi-oki earthquake, the 1763 Aomori-oki earthquake, the 1677 Boso-oki earthquake, and the 1611 Sanriku earthquake. Some trans-Pacific tsunamis such as the 1700 Cascadia and 1960 Chilean tsunamis also caused severe damage along the Sanriku coast and these tsunami deposits may be also preserved.

Goto, T.; Satake, K.; Sugai, T.; Ishibe, T.; Harada, T.; Murotani, S.

2013-12-01

308

The 1888 shoreline landslide and tsunami in Trondheimsfjorden, central Norway  

Science.gov (United States)

The 1888 landslide and tsunami along the shore of the bay of Trondheim, central Norway, killed one person and caused major damage to port facilities. Recent bathymetric surveys, high-resolution seismic profiles and CPTU piezocone tests provide detail information about the morphology of the seafloor and landslide mechanisms, which can be used in tsunami simulations. Based on our integrated data set we suggest the 1888 sequence of events started with an initial underwater landslide near-shore, by detachment along a weak clayey sediment layer. Geomorphology indicates the landslide transformed rapidly into a debris flow, which subsequently triggered slope failures on the flanks of a deep underwater channel. One of the slope failures is associated with the triggering of the 1888 tsunami wave, with documented run-up heights of several meters. The interpreted sequence of events is supported by eyewitness testimony and further validated by slope stability analysis, slide dynamics modelling and 2D tsunami simulations.

L'Heureux, J.-S.; Glimsdal, S.; Longva, O.; Hansen, L.; Harbitz, C. B.

2011-03-01

309

TSUNAMI HAZARD ASSESSMENT IN THE NORTHERN AEGEAN SEA  

Directory of Open Access Journals (Sweden)

Full Text Available Emergency planning for the assessment of tsunami hazard inundation and of secondary effects of erosion and landslides, requires mapping that can help identify coastal areas that are potentially vulnerable. The present study reviews tsunami susceptibility mapping for coastal areas of Turkey and Greece in the Aegean Sea. Potential tsunami vulnerable locations were identified from LANDSAT ETM imageries, Shuttle Radar Topography Mission (SRTM, 2000 data and QuickBird imageries and from a GIS integrated spatial database. LANDSAT ETM and Digital Elevation Model (DEM data derived by the SRTM-Mission were investigated to help detect traces of past flooding events. LANDSAT ETM imageries, merged with digitally processed and enhanced SRTM data, clearly indicate the areas that may be prone to flooding if catastrophic tsunami events or storm surges occur.

Barbara Theilen-Willige

2008-01-01

310

Assessing tsunami vulnerability, an example from Herakleio, Crete  

Digital Repository Infrastructure Vision for European Research (DRIVER)

Recent tsunami have caused massive loss of life, destruction of coastal infrastructures and disruption to economic activity. To date, tsunami hazard studies have concentrated on determining the frequency and magnitude of events and in the production of simplistic flood maps. In general, such maps appear to have assumed a uniform vulnerability of population, infrastructure and business. In reality however, a complex set of factors interact to produce a pattern of vulnerability that vari...

2003-01-01

311

Assessing tsunami vulnerability, an example from Herakleio, Crete  

Digital Repository Infrastructure Vision for European Research (DRIVER)

Recent tsunami have caused massive loss of life, destruction of coastal infrastructures and disruption to economic activity. To date, tsunami hazard studies have concentrated on determining the frequency and magnitude of events and in the production of simplistic flood maps. In general, such maps appear to have assumed a uniform vulnerability of population, infrastructure and business. In reality however, a complex set of factors interact to produce a pattern of vulnerability that varies spat...

2003-01-01

312

Field Survey on The Coastal Impacts of March 11, 2011 Great East Japan Tsunami  

Science.gov (United States)

The March 11, 2011 Great East Japan Earthquake triggered a tsunami and caused massive damage in NE coast of Japan. A field survey has been performed in the tsunami hit areas. A filed survey has been performed in Sendai Airport, Yuriage, Natori, Sendai port, Taro, Miyako, Yamada, Kamaishi, Rikuzentakata, Ofunato and Kesennuma. The tsunami energy focused inside narrow bays and huge volumes of water overtopped tsunami walls, penetrated from the estuaries and propagated along the rivers inland and on the low lands with the extensive damage on the coastal settlements. The measurements and observations on tsunami nearshore amplitude, flow and overtopping characteristics, current velocities, flow depth, damage levels are presented. A series of simulations covering the generation, propagation and coastal amplification of the tsunami is performed. The simulation resuts are used for comparisons with deep water measurement data and used to input the incoming tsunami characteristics to the selected bays (i.e. Kamaishi and Miyako) in order to investigate and visualize the tsunami behaviour in the bays. The fine grid simulations of the tsunami in Kamaishi bay are performed using the bathymetric data with and without breakwater. Hence the existance of the protection structures and their performance are compared by using the modeling results. Furthermore, the tsunami impact, building response and tsunami mitigation strategies are discussed. As summary, the observations from the tsunami impact of 11 March 2011 tsunami is presented. The results of simulations focusing on tsunami inundation which covers teh computed nearshore tsunami parameters with emphasis in Kamaishi and Miyako are discussed. The findings concerning structural damage to different structures are presented.

Yalciner, A. C.; Suppasri, A.; Mas, E.; Kalligeris, N.; Necmioglu, O.; Imamura, F.; Ozer, C.; Zaytsev, A.; Synolakis, C.; Takahashi, S.; Tomita, T.; Yon, G.

2011-12-01

313

Food Safety After a Tsunami  

Science.gov (United States)

... Hurricanes Landslides Tornadoes Tsunamis Volcanoes Wildfires Winter Weather Food Safety After a Tsunami To prevent foodborne diseases, ... baby formula that requires no added water. Keeping Foods Cold If available, dry ice can be used ...

314

Tsunami risk assessment in Indonesia  

Digital Repository Infrastructure Vision for European Research (DRIVER)

In the framework of the German Indonesian Tsunami Early Warning System (GITEWS) the assessment of tsunami risk is an essential part of the overall activities. The scientific and technical approach for the tsunami risk assessment has been developed and the results are implemented in the national Indonesian Tsunami Warning Centre and are provided to the national and regional disaster management and spatial planning institutions in Indonesia.

The paper explains the underlyin...

Strunz, G.; Post, J.; Zosseder, K.; Wegscheider, S.; Mu?ck, M.; Riedlinger, T.; Mehl, H.; Dech, S.; Birkmann, J.; Gebert, N.; Harjono, H.; Anwar, H. Z.; Sumaryono; Khomarudin, R. M.; Muhari, A.

2011-01-01

315

Historical tsunami database for France and its overseas territories  

Directory of Open Access Journals (Sweden)

Full Text Available A search and analysis of a large number of historical documents has made it possible: (i to discover so-far unknown tsunamis that have hit the French coasts during the last centuries, and (ii conversely, to disprove the tsunami nature of several events referred to in recent catalogues. This information has been structured into a database and also made available as a website (tsunamis.f/" target="_blank">http://www.tsunamis.fr that is accessible in French, English and Spanish. So far 60 genuine ("true" tsunamis have been described (with their dates, causes, oceans/seas, places observed, number of waves, flood and ebb distances, run-up, and intensities and referenced against contemporary sources. Digitized documents are accessible online. In addition, so as to avoid confusion, tsunamis revealed as "false" or "doubtful" have been compiled into a second catalogue.

Both the database and the website are updated annually corresponding to the state of knowledge, so as to take into account newly discovered historical references and the occurrence of new tsunamis on the coasts of France and many of its overseas territories: Guadeloupe, Martinique, French Guiana, New Caledonia, Réunion, and Mayotte.

J. Lambert

2011-04-01

316

THE INDIAN OCEAN TSUNAMI OF 26 DECEMBER 2004 Analysis of Seismic Source Mechanism  

Digital Repository Infrastructure Vision for European Research (DRIVER)

Based on the keyboard model of tsunamigenic earthquakes, an analysis was performed of the physical aspects of the 26 December 2004 earthquake off Sumatra and of the seismic source of the great tsunami generated in the Indian Ocean. A simplified keyboard model with vertical displacements of keyboard blocks was used for the numerical simulation in defining the tsunami’s generation source and, based on known bathymetry, its subsequent propagation across the Indian Ocean basin. The numerical si...

2012-01-01

317

Owen Ridge deep-water submarine landslides: implications for tsunami hazard along the Oman coast  

Digital Repository Infrastructure Vision for European Research (DRIVER)

The recent discovery of voluminous submarine landslides along the Owen Ridge may represent a source of tsunami hazard for the nearby Oman coast. We assess the severity of this potential hazard by performing numerical simulations of tsunami generation and propagation from the biggest landslide (40 km3 in volume) observed along the Owen Ridge. A finite-difference model, assimilating the landslide to a visco-plastic flow, simulates tsunami generation. Computation res...

Rodriguez, M.; Chamot Rooke, N.; He?bert, H.; Fournier, M.; Huchon, P.

2013-01-01

318

Short Wave Amplification and Extreme Runup by the 2011 Tohoku Tsunami  

Science.gov (United States)

Watermarks found during the post-event surveys of the 2011 Tohoku tsunami confirmed extreme runup heights at several locations along the central to northern part of the Sanriku coast, Japan. We measured the maximum height of nearly 40 m above mean sea level at a narrow coastal valley of the Aneyoshi district. Wave records by offshore GPS-buoys suggest that the remarkably high runup was associated with a leading, impulsive crest of the tsunami amplified by local bathymetry and topography. In order to elucidate the underlying amplification mechanism, we apply a numerical model to reproduce the measured distribution of tsunami heights along the target coastline. A series of numerical tests under different boundary conditions suggests that a spectral component with a dominant period of 4-5 min in the leading wave play a key role in generating the extreme runup. Further analyses focusing on the Aneyoshi district confirm that the short wavelength component undergoes critical amplification in a narrow inlet. Our findings highlight the importance of resolving offshore waveforms as well as local bathymetry and topography when simulating extreme runup events.

Shimozono, Takenori; Cui, Haiyang; Pietrzak, Julie D.; Fritz, Hermann M.; Okayasu, Akio; Hooper, Andrew J.

2014-03-01

319

Sources of information for tsunami forecasting in New Zealand  

Science.gov (United States)

Tsunami science has evolved considerably in the last two decades due to technological advancements which also helped push for better numerical modelling of the tsunami phases (generation to inundation). The deployment of DART buoys has also been a considerable milestone in tsunami forecasting. Tsunami forecasting is one of the parts that tsunami modelling feeds into and is related to response, preparedness and planning. Usually tsunami forecasting refers to short-term forecasting that takes place in real-time after a tsunami has or appears to have been generated. In this report we refer to all types of forecasting (short-term or long-term) related to work in advance of a tsunami impacting a coastline that would help in response, planning or preparedness. We look at the standard types of data (seismic, GPS, water level) that are available in New Zealand for tsunami forecasting, how they are currently being used, other ways to use these data and provide recommendations for better utilisation. The main findings are: -Current investigations of the use of seismic parameters quickly obtained after an earthquake, have potential to provide critical information about the tsunamigenic potential of earthquakes. Further analysis of the most promising methods should be undertaken to determine a path to full implementation. -Network communication of the largest part of the GPS network is not currently at a stage that can provide sufficient data early enough for tsunami warning. It is believed that it has potential, but changes including data transmission improvements may have to happen before real-time processing oriented to tsunami early warning is implemented on the data that is currently provided. -Tide gauge data is currently under-utilised for tsunami forecasting. Spectral analysis, modal analysis based on identified modes and arrival times extracted from the records can be useful in forecasting. -The current study is by no means exhaustive of the ways the different types of data can be used. We are only presenting an overview of what can be done. More extensive studies with each one of the types of data collected by GeoNet and other relevant networks will help improve tsunami forecasting in New Zealand.

Barberopoulou, A.; Ristau, J. P.; D'Anastasio, E.; Wang, X.

2013-12-01

320

Calibration of a real-time tsunami detection algorithm for sites with no instrumental tsunami records: application to coastal tide-gauge stations in eastern Sicily, Italy  

Science.gov (United States)

Coastal tide gauges play a very important role in a tsunami warning system, since sea-level data are needed for a correct evaluation of the tsunami threat, and the tsunami arrival has to be recognized as early as possible. Real-time tsunami detection algorithms serve this purpose. For an efficient detection, they have to be calibrated and adapted to the specific local characteristics of the site where they are installed, which is easily done when the station has recorded a sufficiently large number of tsunamis. In this case the recorded database can be used to select the best set of parameters enhancing the discrimination power of the algorithm and minimizing the detection time. This chance is however rare, since most of the coastal tide-gauge stations, either historical or of new installation, have recorded only a few tsunamis in their lifetimes, if any. In this case calibration must be carried out by using synthetic tsunami signals, which poses the problem of how to generate them and how to use them. This paper investigates this issue and proposes a calibration approach by using as an example a specific case, which is the calibration of a real-time detection algorithm called TEDA (Tsunami Early Detection Algorithm) for two stations (namely Tremestieri and Catania) in eastern Sicily, Italy, which were recently installed in the frame of the Italian project TSUNET, aiming at improving the tsunami monitoring capacity in a region that is one of the most hazardous tsunami areas of Italy and of the Mediterranean.

Bressan, L.; Zaniboni, F.; Tinti, S.

2013-12-01

 
 
 
 
321

Tsunami-genic turbidity currents: observation and estimation of flow conditions (Invited)  

Science.gov (United States)

Turbidity current deposits (turbidites) have been used to estimate earthquake recurrence intervals from geologic records. Turbidity currents are sediment-laden subaqueous density flows generated by processes such as submarine landslides, river floods and storms. Although various processes can generate turbidity currents, it has been believed that earthquake-induced turbidity currents commonly occur as turbidites in geologic records. Since the turbidity currents were detected immediately after the 1908 Messina and the 1929 Grand-bank earthquakes that are characterized both by the occurrence of large submarine slumps paleo-earthquakes and paleo-tsunamis have been assumed to be recorded as turbidity current deposits (turbidites) in sedimentary sequences and several turbidites have been used to estimate earthquake recurrence intervals. Offshore records offer the potential of good preservation and long temporal span. Thus, seismogenic or tsunamigenic turbidites are important for understanding risk of geohazards. There has not been, however, direct evidence for the generation of turbidity currents by large-scale earthquake-generated tsunamis in the absence of related submarine landslides at subduction margins. Recently, the first real-time record of the turbidity current associated with a great tsunami was reported; in this case with the Mw 9.0, 2011 Tohoku-Oki event. Previously there has been no direct of evidence for the large-scale earthquake in subduction plate margins. After the 2011 Tohoku-Oki earthquake and tsunami, an anomalous event on the sea floor consistent with a turbidity current was recorded by ocean bottom pressure recorders and ocean bottom seismometers deployed off Sendai. Freshly-emplaced turbidites were collected from a wide area of seafloor off the Tohoku coastal region, and then these measurements and sedimentary records were analyzed to determine conditions of the modern tsunamigenic turbidity current. As a preliminary research, we examined the hydraulic conditions for generating turbidity currents that can attain the observed velocity of the turbidity currents generated by 2011 Tohoku-Oki tsunami. As a result, the numerical model of sheet-like turbidity currents revealed that the only 0.1 vol. % sediment cloud suspended by the tsunami on the continental shelf can produce a turbidity current that can transport the OBP. The numerical model also suggests that this condition can be easily attained by the 2011 Tohoku-Oki tsunami. This study reveals the features of a tsunamigenic turbidity current that was spatially extensive. This can be interpreted as a consequence of the ability of large tsunamis to erode broad areas of the upper continental slope, whereas many other mechanisms such as slope failure for turbidity current genesis occur mainly in limited areas, and are more likely to be point sources. We anticipate our discovery to be a starting point for more detailed characterization of modern tsunamigenic turbidites toward their identification in geologic records. Future investigation of the sediment cores taken from the seafloor off the Tohoku region will provide further characterization of tsunamigenic turbidites, which can aid in the development of criteria to distinguish them from other types of turbidites.

Naruse, H.; Arai, K.; Izumi, N.; Yokokawa, M.; Miura, R.; Kawamura, K.; Hino, R.; Ito, Y.; Inazu, D.; Murayama, M.; Kasaya, T.

2013-12-01

322

Surviving a Tsunami: Lessons from Chile, Hawaii, and Japan  

Science.gov (United States)

This report contains true stories that illustrate how to survive (and how not to survive) a tsunami. It is meant for people who live, work, or play along coasts that tsunamis may strike. The stories are personal accounts selected from interviews with people who survived a Pacific Ocean tsunami generated by the magnitude 9.5 earthquake that occurred along the coast of Chile on May 22, 1960. Important points include the necessity to heed all warnings (official and natural), head for higher ground, expect many waves, and not to attempt to recover personal belongings.

323

Handling of the Generation of Primary Events in Gauss, the LHCb Simulation Framework  

CERN Multimedia

The LHCb simulation application, Gauss, consists of two independent phases, the generation of the primary event and the tracking of particles produced in the experimental setup. For the LHCb experimental program it is particularly important to model B meson decays: the EvtGen code developed in CLEO and BaBar has been chosen and customized for non coherent B production as occuring in pp collisions at the LHC. The initial proton-proton collision is provided by a different generator engine, currently Pythia 6 for massive production of signal and generic pp collisions events. Beam gas events, background events originating from proton halo, cosmics and calibration events for different detectors can be generated in addition to pp collisions. Different generator packages are available in the physics community or specifically developed in LHCb, and are used for the different purposes. Running conditions affecting the events generated such as the size of the luminous region, the number of collisions occuring in a bunc...

Corti, G; Brambach, T; Brook, N H; Gauvin, N; Harrison, K; Harrison, P; He, J; Ilten, P J; Jones, C R; Lieng, M H; Manca, G; Miglioranzi, S; Robbe, P; Vagnoni, V; Whitehead, M; Wishahi, J

2010-01-01

324

Handling of the generation of primary events in Gauss, the LHCb simulation framework  

CERN Document Server

The LHCb simulation application, Gauss, consists of two independent phases, the generation of the primary event and the tracking of particles produced in the experimental setup. For the LHCb experimental program it is particularly important to model $B$ meson decays: the EvtGen code developed in CLEO and BABAR has been chosen and customized for non coherent $B$ production as occuring in $pp$ collisions at the LHC. The initial proton-proton collision is provided by a different generator engine, currently PYTHIA 6 for massive production of signal and generic $pp$ collisions events. Beam gas events, background events originating from proton halo, cosmics and calibration events for different detectors can be generated in addition to $pp$ collisions. Different generator packages are available in the physics community or specifically developed in LHCb, and are used for the different purposes. Running conditions affecting the events generated such as the size of the luminous region, the number of collisions occurrin...

Belyaev, I; Brook, N H; Gauvin, N; Corti, G; Harrison, K; Harrison, P F; He, J; Hilten, P H; Jones, C R; Lieng, M; Manca, G; Miglioranzi, S; Robbe, P; Vagnoni, V; Whitehead, M; Wishahi, J

2010-01-01

325

Handling of the generation of primary events in Gauss, the LHCb simulation framework  

CERN Document Server

The LHCb simulation application, Gauss, consists of two independent phases, the generation of the primary event and the tracking of particles produced in the experimental setup. For the LHCb experimental program it is particularly important to model B meson decays: the EvtGen code developed in CLEO and BABAR has been chosen and customized for non-coherent B production as occuring in pp collisions at the LHC. The initial proton-proton collision is provided by a different generator engine, currently PYTHIA 6 for massive production of signal and generic pp collisions events. Beam gas events, background events originating from proton halo, cosmics and calibration events for different detectors can be generated in addition to pp collisions. Different generator packages as available in the physics community or specifically developed in LHCb are used for the different purposes. Running conditions affecting the generated events such as the size of the luminous region, the number of collisions occuring in a bunch cros...

Belyaev, I; Brook, N H; Gauvin, N; Corti, G; Harrison, K; Harrison, P F; He, J; Jones, C R; Lieng, M; Manca, G; Miglioranzi, S; Robbe, P; Vagnoni, V; Whitehead, M; Wishahi, J

2011-01-01

326

Plasmon tsunamis on metallic nanoclusters  

Science.gov (United States)

A model is constructed to describe inelastic scattering events accompanying electron capture by a highly charged ion flying by a metallic nanosphere. The electronic energy liberated by an electron leaving the Fermi level of the metal and dropping into a deep Rydberg state of the ion is used to increase the ion kinetic energy and, simultaneously, to excite multiple surface plasmons around the positively charged hole left behind on the metal sphere. This tsunami-like phenomenon manifests itself as periodic oscillations in the kinetic energy gain spectrum of the ion. The theory developed here extends our previous treatment (Lucas et al 2011 New J. Phys. 13 013034) of the Arq+/C60 charge exchange system. We provide an analysis of how the individual multipolar surface plasmons of the metallic sphere contribute to the formation of the oscillatory gain spectrum. Gain spectra showing characteristic, tsunami-like oscillations are simulated for Ar15+ ions capturing one electron in distant collisions with Al and Na nanoclusters.

Lucas, A. A.; Sunjic, M.

2012-03-01

327

Near-Field Tsunami Models with Rapid Earthquake Source Inversions from Land and Ocean-Based Observations: The Potential for Forecast and Warning  

Science.gov (United States)

Computation of predicted tsunami wave heights and runup in the regions adjacent to large earthquakes immediately after rupture initiation remains a challenging problem. Limitations of traditional seismological instrumentation in the near field which cannot be objectively employed for real-time inversions and the non-unique source inversion results are a major concern for tsunami modelers. Employing near-field seismic, GPS and wave gauge data from the Mw 9.0 2011 Tohoku-oki earthquake, we test the capacity of static finite fault slip models obtained from newly developed algorithms to produce reliable tsunami forecasts. First we demonstrate the ability of seismogeodetic source models determined from combined land-based GPS and strong motion seismometers to forecast near-source tsunamis in ~3 minutes after earthquake origin time (OT). We show that these models, based on land-borne sensors only tend to underestimate the tsunami but are good enough to provide a realistic first warning. We then demonstrate that rapid ingestion of offshore shallow water (100 - 1000 m) wave gauge data significantly improves the model forecasts and possible warnings. We ingest data from 2 near-source ocean-bottom pressure sensors and 6 GPS buoys into the earthquake source inversion process. Tsunami Green functions (tGFs) are generated using the GeoClaw package, a benchmarked finite volume code with adaptive mesh refinement. These tGFs are used for a joint inversion with the land-based data and substantially improve the earthquake source and tsunami forecast. Model skill is assessed by detailed comparisons of the simulation output to 2000+ tsunami runup survey measurements collected after the event. We update the source model and tsunami forecast and warning at 10 min intervals. We show that by 20 min after OT the tsunami is well-predicted with a high variance reduction to the survey data and by ~30 minutes a model that can be considered final, since little changed is observed afterwards, is achieved. This is an indirect approach to tsunami warning, it relies on automatic determination of the earthquake source prior to tsunami simulation. It is more robust than ad-hoc approaches because it relies on computation of a finite-extent centroid moment tensor to objectively determine the style of faulting and the fault plane geometry on which to launch the heterogeneous static slip inversion. Operator interaction and physical assumptions are minimal. Thus, the approach can provide the initial conditions for tsunami simulation (seafloor motion) irrespective of the type of earthquake source and relies heavily on oceanic wave gauge measurements for source determination. It reliably distinguishes among strike-slip, normal and thrust faulting events, all of which have been observed recently to occur in subduction zones and pose distinct tsunami hazards.

Melgar, D.; Bock, Y.; Crowell, B. W.; Haase, J. S.

2013-12-01

328

MERADGEN: Monte Carlo generator for the simulation of radiative events in polarized Moller scattering  

International Nuclear Information System (INIS)

The Monte Carlo generator MERADGEN for the simulation of QED radiative events in polarized Moller scattering has been developed. Analytical integration wherever it is possible provides rather fast generation. Some numerical tests and histograms are presented

2006-01-01

329

Sensor-Generated Time Series Events: A Definition Language  

Digital Repository Infrastructure Vision for European Research (DRIVER)

There are now a great many domains where information is recorded by sensors over a limited time period or on a permanent basis. This data flow leads to sequences of data known as time series. In many domains, like seismography or medicine, time series analysis focuses on particular regions of interest, known as events, whereas the remainder of the time series contains hardly any useful information. In these domains, there is a need for mechanisms to identify and locate such events. In this pa...

Aurea Anguera; Lara, Juan A.; David Lizcano; Maria Aurora Martínez; Juan Pazos

2012-01-01

330

The 1867 Virgin Island Tsunami  

Directory of Open Access Journals (Sweden)

Full Text Available The 1867 Virgin Island Tsunami reached large magnitude on the coasts of the Caribbean Islands. A maximum tsunami height of 10 m was reported for two coastal locations (Deshaies and Sainte-Rose in Guadeloupe. Modelling of the 1867 tsunami is performed in the framework of the nonlinear shallow-water theory. The directivity of the tsunami wave source in the Caribbean Sea according to the assumed initial waveform is investigated. The tsunami records at the several coastal regions in the Lesser Antilles, Virgin Islands, Puerto Rico and South America are simulated. The comparison between the computed and observed data is in reasonable agreement.

N. Zahibo

2003-01-01

331

The 17 July 2006 Tsunami earthquake in West Java, Indonesia  

Science.gov (United States)

A tsunami earthquake (Mw = 7.7) occurred south of Java on 17 July 2006. The event produced relatively low levels of high-frequency radiation, and local felt reports indicated only weak shaking in Java. There was no ground motion damage from the earthquake, but there was extensive damage and loss of life from the tsunami along 250 km of the southern coasts of West Java and Central Java. An inspection of the area a few days after the earthquake showed extensive damage to wooden and unreinforced masonry buildings that were located within several hundred meters of the coast. Since there was no tsunami warning system in place, efforts to escape the large waves depended on how people reacted to the earthquake shaking, which was only weakly felt in the coastal areas. This experience emphasizes the need for adequate tsunami warning systems for the Indian Ocean region.

Mori, J.; Mooney, W. D.; Afnimar; Kurniawan, S.; Anaya, A. I.; Widiyantoro, S.

2007-01-01

332

Constraining shallow slip and tsunami excitation in megathrust ruptures using seismic and ocean acoustic waves recorded on ocean-bottom sensor networks  

Science.gov (United States)

Great earthquakes along subduction-zone plate boundaries, like the 2011 magnitude 9.0 Tohoku-Oki, Japan, event, deform the seafloor to generate massive tsunamis. Tsunami wave heights near shore are greatest when excitation occurs far offshore near the trench, where water depths are greatest and fault slip is shallow. The Tohoku event, featuring over 30 m of slip near the trench, exemplifies this hazard. Unfortunately the rupture process that far offshore is poorly constrained with land-based geodetic and even most seafloor deformation measurements, and seismic inferences of shallow slip are often nonunique. Here we demonstrate, through dynamic rupture simulations of the Tohoku event, that long-period guided waves in the ocean (specifically, leaking oceanic P-wave modes known as PL waves) can resolve the shallow rupture process and tsunami excitation near the trench. With predicted pressure changes of ?0.1-1 MPa along most of the seafloor landward of the trench, and periods of several seconds, these PL waves should be observable with ocean-bottom pressure sensors and/or seismometers. With cabled sensor networks like those being deployed offshore Japan and in other subduction zones, these waves could be used to rapidly quantify shallow slip and near-trench seafloor uplift and improve local tsunami early warning systems.

Kozdon, Jeremy E.; Dunham, Eric M.

2014-06-01

333

India's archive of past massive erosional events  

Science.gov (United States)

The 2004 Indian Ocean Tsunami event devastated a number of major coastal regions in South Asia, including the Tamil Nadu coast of India. In many areas on the east coast of India, distinct deposits of tsunami sands drape the landscape and overlie the muddy deposits of the coastal plain. Using erosional, as well as depositional features of the 2004 tsunami as proxy for past events, we present new subsurface evidence of past erosional events along the south-east coast of India.

Nair, R. R.

2009-12-01

334

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)

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 inform decision makers. The SAFRR Tsunami Scenario is organized by a coordinating committee with several working groups, including Earthquake Source, Paleotsunami/Geology Field Work, Tsunami Modeling, Engineering and Physical Impacts, Ecological Impacts, Emergency Management and Education, Social Vulnerability, Economic and Business Impacts, and Policy. In addition, the tsunami scenario process is being assessed and evaluated by researchers from the Natural Hazards Center at the University of Colorado at Boulder. The source event, defined by the USGS' Tsunami Source Working Group, is an earthquake similar to the 2011 Tohoku event, but set in the Semidi subduction sector, between Kodiak Island and the Shumagin Islands off the Pacific coast of the Alaska Peninsula. The Semidi sector is probably late in its earthquake cycle and comparisons of the geology and tectonic settings between Tohoku and the Semidi sector suggest that this location is appropriate. Tsunami modeling and inundation results have been generated for many areas along the California coast and elsewhere, including current velocity modeling for the ports of Los Angeles, Long Beach, and San Diego, and Ventura Harbor. Work on impacts to Alaska and Hawaii will follow. Note: Costas Synolakis (USC) is also an author of this abstract.

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

335

Forecasting Wave Amplitudes after the Arrival of a Tsunami  

Science.gov (United States)

The destructive Pacific Ocean tsunami generated off the east coast of Honshu, Japan, on 11 March 2011 prompted the West Coast and Alaska Tsunami Warning Center (WCATWC) to issue a tsunami warning and advisory for the coastal regions of Alaska, British Columbia, Washington, Oregon, and California. Estimating the length of time the warning or advisory would remain in effect proved difficult. To address this problem, the WCATWC developed a technique to estimate the amplitude decay of a tsunami recorded at tide stations within the Warning Center's Area of Responsibly (AOR). At many sites along the West Coast of North America, the tsunami wave amplitudes will decay exponentially following the arrival of the maximum wave (uc(Mofjeld) et al., Nat Hazards 22:71-89, 2000). To estimate the time it will take before wave amplitudes drop to safe levels, the real-time tide gauge data are filtered to remove the effects of tidal variations. The analytic envelope is computed and a 2 h sequence of amplitude values following the tsunami peak is used to obtain a least squares fit to an exponential function. This yields a decay curve which is then combined with an average West Coast decay function to provide an initial tsunami amplitude-duration forecast. This information may then be provided to emergency managers to assist with response planning.

Nyland, David; Huang, Paul

2013-08-01

336

CARIBE WAVE/LANTEX Caribbean and Western Atlantic Tsunami Exercises  

Science.gov (United States)

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 Seismic Network. The CARIBE WAVE/LANTEX 13 scenario simulated a tsunami generated by a magnitude 8.5 earthquake originating north of Oranjestad, Aruba in the Caribbean Sea. For the first time earthquake impact was included in addition to expected tsunami impact. The initial message was issued by the warning centers over the established channels, while different mechanisms were then used by participants for further dissemination. The enhanced PTWC tsunami products for the Caribbean were also made available to the participants. To provide feedback on the exercise an online survey tool with 85 questions was used. The survey demonstrated satisfaction with exercise, timely receipt of bulletins and interest in the enhanced PTWC products. It also revealed that while 93% of the countries had an activation and response process, only 59% indicated that they also had an emergency response plan for tsunamis and even fewer had tsunami evacuation plans and inundation maps. Given that 80% of those surveyed indicated that CARIBE WAVE should be conducted annually, CARIBE EWS decided that the next exercise be held on March 26, 2014, instead of waiting until 2015.

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

2013-12-01

337

Flux Transfer Events: 1. generation mechanism for strong southward IMF  

Digital Repository Infrastructure Vision for European Research (DRIVER)

We use a global numerical model of the interaction of the solar wind and the interplanetary magnetic field with Earth's magnetosphere to study the formation process of Flux Transfer Events (FTEs) during strong southward IMF. We find that: (i) The model produces essentially all observational features expected for FTEs, in particular the bipolar signature of the magnetic field BN component, the correct polarity, duration, and intermittency of that ...

Raeder, J.

2006-01-01

338

Analysis of XXI Century Disasters in the National Geophysical Data Center Historical Natural Hazard Event Databases  

Science.gov (United States)

The National Geophysical Data Center (NGDC) maintains a global historical event database of tsunamis, significant earthquakes, and significant volcanic eruptions. The database includes all tsunami events, regardless of intensity, as well as earthquakes and volcanic eruptions that caused fatalities, moderate damage, or generated a tsunami. Event date, time, location, magnitude of the phenomenon, and socio-economic information are included in the database. Analysis of the NGDC event database reveals that the 21st century began with earthquakes in Gujarat, India (magnitude 7.7, 2001) and Bam, Iran (magnitude 6.6, 2003) that killed over 20,000 and 31,000 people, respectively. These numbers were dwarfed by the numbers of earthquake deaths in Pakistan (magnitude 7.6, 2005-86,000 deaths), Wenchuan, China (magnitude 7.9, 2008-87,652 deaths), and Haiti (magnitude 7.0, 2010-222,000 deaths). The Haiti event also ranks among the top ten most fatal earthquakes. The 21st century has observed the most fatal tsunami in recorded history-the 2004 magnitude 9.1 Sumatra earthquake and tsunami that caused over 227,000 deaths and 10 billion damage in 14 countries. Six years later, the 2011 Tohoku, Japan earthquake and tsunami, although not the most fatal (15,000 deaths and 5,000 missing), could cost Japan's government in excess of 300 billion-the most expensive tsunami in history. Volcanic eruptions can cause disruptions and economic impact to the airline industry, but due to their remote locations, fatalities and direct economic effects are uncommon. Despite this fact, the second most expensive eruption in recorded history occurred in the 21st century-the 2010 Merapi, Indonesia volcanic eruption that resulted in 324 deaths, 427 injuries, and $600 million in damage. NGDC integrates all natural hazard event datasets into one search interface. Users can find fatal tsunamis generated by earthquakes or volcanic eruptions. The user can then link to information about the related runup observations (e.g. maximum wave height) and the source earthquake or volcano. If available, damage photographs and plots of water level data can also be viewed. The data are accessible online via tables, reports, and a new state-of-the-art interactive map viewer. These data and access capabilities help coastal communities assess their risks, identify hazards, and promote public awareness of tsunamis and earthquakes.

Dunbar, P. K.; McCullough, H. L.

2011-12-01

339

EXPERIMENTAL AND COMPUTATIONAL ACTIVITIES AT THE OREGON STATE UNIVERSITY NEES TSUNAMI RESEARCH FACILITY  

Digital Repository Infrastructure Vision for European Research (DRIVER)

A diverse series of research projects have taken place or are underway at the NEES Tsunami Research Facility at Oregon State University. Projects range from the simulation of the processes and effects of tsunamis generated by sub-aerial and submarine landslides (NEESR, Georgia Tech.), model comparisons of tsunami wave effects on bottom profiles and scouring (NEESR, Princeton University), model comparisons of wave induced motions on rigid and free bodies (Shared-Use, Cornell), numerical model ...

2009-01-01

340

Tiché tsunami bez hranic.  

Czech Academy of Sciences Publication Activity Database

. Ro?. 6, ?. 24 (2008), s. 14. ISSN 1801-1446Výzkumný zám?r: CEZ:AV0Z70280505Klí?ová slova: food crisisKód oboru RIV: AO - Sociologie, demografiehttp://www.respekt.cz/search.php?f_search_text=tich%E9+tsunami+bez+hranic

Kone?ný, Tomáš

 
 
 
 
341

Scenarios of local tsunamis in the China Seas by Boussinesq model  

Science.gov (United States)

The Okinawa Trench in the East China Sea and the Manila Trench in the South China Sea are considered to be the regions with high risk of potential tsunamis induced by submarine earthquakes. Tsunami waves will impact the southeast coast of China if tsunamis occur in these areas. In this paper, the horizontal two-dimensional Boussinesq model is used to simulate tsunami generation, propagation, and runup in a domain with complex geometrical boundaries. The temporary varying bottom boundary condition is adopted to describe the initial tsunami waves motivated by the submarine faults. The Indian Ocean tsunami is simulated by the numerical model as a validation case. The time series of water elevation and runup on the beach are compared with the measured data from field survey. The agreements indicate that the Boussinesq model can be used to simulate tsunamis and predict the waveform and runup. Then, the hypothetical tsunamis in the Okinawa Trench and the Manila Trench are simulated by the numerical model. The arrival time and maximum wave height near coastal cities are predicted by the model. It turns out that the leading depression N-wave occurs when the tsun