WorldWideScience

Sample records for volcanoes earthquakes impact

  1. Organizational changes at Earthquakes & Volcanoes

    Science.gov (United States)

    Gordon, David W.

    1992-01-01

    Primary responsibility for the preparation of Earthquakes & Volcanoes within the Geological Survey has shifted from the Office of Scientific Publications to the Office of Earthquakes, Volcanoes, and Engineering (OEVE). As a consequence of this reorganization, Henry Spall has stepepd down as Science Editor for Earthquakes & Volcanoes(E&V).

  2. Volcanoes: observations and impact

    Science.gov (United States)

    Thurber, Clifford; Prejean, Stephanie G.

    2012-01-01

    Volcanoes are critical geologic hazards that challenge our ability to make long-term forecasts of their eruptive behaviors. They also have direct and indirect impacts on human lives and society. As is the case with many geologic phenomena, the time scales over which volcanoes evolve greatly exceed that of a human lifetime. On the other hand, the time scale over which a volcano can move from inactivity to eruption can be rather short: months, weeks, days, and even hours. Thus, scientific study and monitoring of volcanoes is essential to mitigate risk. There are thousands of volcanoes on Earth, and it is impractical to study and implement ground-based monitoring at them all. Fortunately, there are other effective means for volcano monitoring, including increasing capabilities for satellite-based technologies.

  3. A remote sensing assessment of the impact of the 2010 Maule, Chile earthquake (Mw 8.8) on the volcanoes of the southern Andes

    Science.gov (United States)

    Pritchard, M. E.; Welch, M.; Jay, J.; Button, N.

    2011-12-01

    There are tantalizing, but controversial, indications that great earthquakes affect arc-wide volcanic activity. For example, analysis of historic eruptions at volcanoes of the southern Andes has shown that 3-4 eruptions were likely seismically triggered by Mw > 8 earthquakes in the Chile subduction zone -- particularly the 1906 and 1960 earthquakes (e.g., Watt et al., 2009). However, the 27 February 2010 Mw 8.8 Maule, Chile earthquake that ruptured the subduction zone between the 1960 and 1906 earthquakes does not appear to have triggered 3-4 volcanic eruptions in the same area in the 12 months after the event. In an effort to understand the relation between a large earthquake and volcanic unrest, we use a variety of satellite instruments to look for more subtle (i.e., not leading to eruption), but detectable change in thermal or deformation activity at the volcanoes of the southern Andes after the Maule earthquake and its aftershocks. For all of the volcanoes in the catalog of the Smithsonian Institution (approximately 80), we use nighttime MODIS and ASTER data to assess the thermal activity and ALOS InSAR data to characterize the surface deformation before and after the earthquake. The ALOS InSAR data are not ideal for detecting changes in deformation before and after the earthquake because of the small number of acquisitions in austral summer as well as ionospheric and tropospheric artifacts. We estimate that we could detect deformation > 5 cm/year. Similarly, the ASTER and MODIS data suffer respectively from poor temporal and spatial resolution of thermal anomalies. We update previous InSAR work that identified at least 8 areas of volcanic deformation in the southern Andes related to eruptive processes, subsidence of past lava flows, or surface uplift not associated with an eruption (Fournier et al., 2010). Of greatest interest are the two volcanic areas with the largest deformation signals between 2007-2008 (both > 15 cm/yr in the radar line of sight): Laguna

  4. Deep long-period earthquakes beneath Washington and Oregon volcanoes

    Science.gov (United States)

    Nichols, M.L.; Malone, S.D.; Moran, S.C.; Thelen, W.A.; Vidale, J.E.

    2011-01-01

    Deep long-period (DLP) earthquakes are an enigmatic type of seismicity occurring near or beneath volcanoes. They are commonly associated with the presence of magma, and found in some cases to correlate with eruptive activity. To more thoroughly understand and characterize DLP occurrence near volcanoes in Washington and Oregon, we systematically searched the Pacific Northwest Seismic Network (PNSN) triggered earthquake catalog for DLPs occurring between 1980 (when PNSN began collecting digital data) and October 2009. Through our analysis we identified 60 DLPs beneath six Cascade volcanic centers. No DLPs were associated with volcanic activity, including the 1980-1986 and 2004-2008 eruptions at Mount St. Helens. More than half of the events occurred near Mount Baker, where the background flux of magmatic gases is greatest among Washington and Oregon volcanoes. The six volcanoes with DLPs (counts in parentheses) are Mount Baker (31), Glacier Peak (9), Mount Rainier (9), Mount St. Helens (9), Three Sisters (1), and Crater Lake (1). No DLPs were identified beneath Mount Adams, Mount Hood, Mount Jefferson, or Newberry Volcano, although (except at Hood) that may be due in part to poorer network coverage. In cases where the DLPs do not occur directly beneath the volcanic edifice, the locations coincide with large structural faults that extend into the deep crust. Our observations suggest the occurrence of DLPs in these areas could represent fluid and/or magma transport along pre-existing tectonic structures in the middle crust. ?? 2010 Elsevier B.V.

  5. High precision relocation of earthquakes at Iliamna Volcano, Alaska

    Science.gov (United States)

    Statz-Boyer, P.; Thurber, C.; Pesicek, J.; Prejean, S.

    2009-01-01

    In August 1996, a period of elevated seismicity commenced beneath Iliamna Volcano, Alaska. This activity lasted until early 1997, consisted of over 3000 earthquakes, and was accompanied by elevated emissions of volcanic gases. No eruption occurred and seismicity returned to background levels where it has remained since. We use waveform alignment with bispectrum-verified cross-correlation and double-difference methods to relocate over 2000 earthquakes from 1996 to 2005 with high precision (~ 100??m). The results of this analysis greatly clarify the distribution of seismic activity, revealing distinct features previously hidden by location scatter. A set of linear earthquake clusters diverges upward and southward from the main group of earthquakes. The events in these linear clusters show a clear southward migration with time. We suggest that these earthquakes represent either a response to degassing of the magma body, circulation of fluids due to exsolution from magma or heating of ground water, or possibly the intrusion of new dikes beneath Iliamna's southern flank. In addition, we speculate that the deeper, somewhat diffuse cluster of seismicity near and south of Iliamna's summit indicates the presence of an underlying magma body between about 2 and 4??km depth below sea level, based on similar features found previously at several other Alaskan volcanoes. ?? 2009 Elsevier B.V.

  6. Volcanoes

    Science.gov (United States)

    ... rock, steam, poisonous gases, and ash reach the Earth's surface when a volcano erupts. An eruption can also cause earthquakes, mudflows and flash floods, rock falls and landslides, acid rain, fires, and even tsunamis. Volcanic gas ...

  7. Radon soil increases before volcano-tectonic earthquakes in Colombia

    International Nuclear Information System (INIS)

    Garzon, G.; Serna, D.; Diago, J.; Moran, C.

    2003-01-01

    Continuous studies of radon concentration changes in soils for the purpose of earthquake monitoring have been carried out in three colombian districts and in the edifices of Galeras and nevado del Ruiz volcanoes since 1995. In zones of active faulting have been measured radon soil emissions between 1000 and 2500 pCi/L. In an intersection of two active geological faults have been measured levels of 25 000 pCi/L. In the present work appears a compilation of examples of the registered anomalous radon emissions in several stations before earthquakes of tectonic character. Examples of registered radon increases before: (1) events of magnitudes between 2 and 4; (2) the occurrence of seismic swarms; and (3) the Quindio (Colombia) earthquake (M w = 6, 2) of January 1999, are described. A model of transport mechanism for the studied isotopes is presented. (orig.)

  8. Long Period Earthquakes Beneath California's Young and Restless Volcanoes

    Science.gov (United States)

    Pitt, A. M.; Dawson, P. B.; Shelly, D. R.; Hill, D. P.; Mangan, M.

    2013-12-01

    The newly established USGS California Volcano Observatory has the broad responsibility of monitoring and assessing hazards at California's potentially threatening volcanoes, most notably Mount Shasta, Medicine Lake, Clear Lake Volcanic Field, and Lassen Volcanic Center in northern California; and Long Valley Caldera, Mammoth Mountain, and Mono-Inyo Craters in east-central California. Volcanic eruptions occur in California about as frequently as the largest San Andreas Fault Zone earthquakes-more than ten eruptions have occurred in the last 1,000 years, most recently at Lassen Peak (1666 C.E. and 1914-1917 C.E.) and Mono-Inyo Craters (c. 1700 C.E.). The Long Valley region (Long Valley caldera and Mammoth Mountain) underwent several episodes of heightened unrest over the last three decades, including intense swarms of volcano-tectonic (VT) earthquakes, rapid caldera uplift, and hazardous CO2 emissions. Both Medicine Lake and Lassen are subsiding at appreciable rates, and along with Clear Lake, Long Valley Caldera, and Mammoth Mountain, sporadically experience long period (LP) earthquakes related to migration of magmatic or hydrothermal fluids. Worldwide, the last two decades have shown the importance of tracking LP earthquakes beneath young volcanic systems, as they often provide indication of impending unrest or eruption. Herein we document the occurrence of LP earthquakes at several of California's young volcanoes, updating a previous study published in Pitt et al., 2002, SRL. All events were detected and located using data from stations within the Northern California Seismic Network (NCSN). Event detection was spatially and temporally uneven across the NCSN in the 1980s and 1990s, but additional stations, adoption of the Earthworm processing system, and heightened vigilance by seismologists have improved the catalog over the last decade. LP earthquakes are now relatively well-recorded under Lassen (~150 events since 2000), Clear Lake (~60 events), Mammoth Mountain

  9. Evaluation of Earthquake-Induced Effects on Neighbouring Faults and Volcanoes: Application to the 2016 Pedernales Earthquake

    Science.gov (United States)

    Bejar, M.; Alvarez Gomez, J. A.; Staller, A.; Luna, M. P.; Perez Lopez, R.; Monserrat, O.; Chunga, K.; Herrera, G.; Jordá, L.; Lima, A.; Martínez-Díaz, J. J.

    2017-12-01

    It has long been recognized that earthquakes change the stress in the upper crust around the fault rupture and can influence the short-term behaviour of neighbouring faults and volcanoes. Rapid estimates of these stress changes can provide the authorities managing the post-disaster situation with a useful tool to identify and monitor potential threads and to update the estimates of seismic and volcanic hazard in a region. Space geodesy is now routinely used following an earthquake to image the displacement of the ground and estimate the rupture geometry and the distribution of slip. Using the obtained source model, it is possible to evaluate the remaining moment deficit and to infer the stress changes on nearby faults and volcanoes produced by the earthquake, which can be used to identify which faults and volcanoes are brought closer to failure or activation. Although these procedures are commonly used today, the transference of these results to the authorities managing the post-disaster situation is not straightforward and thus its usefulness is reduced in practice. Here we propose a methodology to evaluate the potential influence of an earthquake on nearby faults and volcanoes and create easy-to-understand maps for decision-making support after an earthquake. We apply this methodology to the Mw 7.8, 2016 Ecuador earthquake. Using Sentinel-1 SAR and continuous GPS data, we measure the coseismic ground deformation and estimate the distribution of slip. Then we use this model to evaluate the moment deficit on the subduction interface and changes of stress on the surrounding faults and volcanoes. The results are compared with the seismic and volcanic events that have occurred after the earthquake. We discuss potential and limits of the methodology and the lessons learnt from discussion with local authorities.

  10. Precursory earthquakes of the 1943 eruption of Paricutin volcano, Michoacan, Mexico

    Science.gov (United States)

    Yokoyama, I.; de la Cruz-Reyna, S.

    1990-12-01

    Paricutin volcano is a monogenetic volcano whose birth and growth were observed by modern volcanological techniques. At the time of its birth in 1943, the seismic activity in central Mexico was mainly recorded by the Wiechert seismographs at the Tacubaya seismic station in Mexico City about 320 km east of the volcano area. In this paper we aim to find any characteristics of precursory earthquakes of the monogenetic eruption. Though there are limits in the available information, such as imprecise location of hypocenters and lack of earthquake data with magnitudes under 3.0. The available data show that the first precursory earthquake occurred on January 7, 1943, with a magnitude of 4.4. Subsequently, 21 earthquakes ranging from 3.2 to 4.5 in magnitude occurred before the outbreak of the eruption on February 20. The (S - P) durations of the precursory earthquakes do not show any systematic changes within the observational errors. The hypocenters were rather shallow and did not migrate. The precursory earthquakes had a characteristic tectonic signature, which was retained through the whole period of activity. However, the spectra of the P-waves of the Paricutin earthquakes show minor differences from those of tectonic earthquakes. This fact helped in the identification of Paricutin earthquakes. Except for the first shock, the maximum earthquake magnitudes show an increasing tendency with time towards the outbreak. The total seismic energy released by the precursory earthquakes amounted to 2 × 10 19 ergs. Considering that statistically there is a threshold of cumulative seismic energy release (10 17-18ergs) by precursory earthquakes in polygenetic volcanoes erupting after long quiescence, the above cumulative energy is exceptionally large. This suggests that a monogenetic volcano may need much more energy to clear the way of magma passage to the earth surface than a polygenetic one. The magma ascent before the outbreak of Paricutin volcano is interpretable by a model

  11. Seismic swarm associated with the 2008 eruption of Kasatochi Volcano, Alaska: earthquake locations and source parameters

    Science.gov (United States)

    Ruppert, Natalia G.; Prejean, Stephanie G.; Hansen, Roger A.

    2011-01-01

    An energetic seismic swarm accompanied an eruption of Kasatochi Volcano in the central Aleutian volcanic arc in August of 2008. In retrospect, the first earthquakes in the swarm were detected about 1 month prior to the eruption onset. Activity in the swarm quickly intensified less than 48 h prior to the first large explosion and subsequently subsided with decline of eruptive activity. The largest earthquake measured as moment magnitude 5.8, and a dozen additional earthquakes were larger than magnitude 4. The swarm exhibited both tectonic and volcanic characteristics. Its shear failure earthquake features were b value = 0.9, most earthquakes with impulsive P and S arrivals and higher-frequency content, and earthquake faulting parameters consistent with regional tectonic stresses. Its volcanic or fluid-influenced seismicity features were volcanic tremor, large CLVD components in moment tensor solutions, and increasing magnitudes with time. Earthquake location tests suggest that the earthquakes occurred in a distributed volume elongated in the NS direction either directly under the volcano or within 5-10 km south of it. Following the MW 5.8 event, earthquakes occurred in a new crustal volume slightly east and north of the previous earthquakes. The central Aleutian Arc is a tectonically active region with seismicity occurring in the crusts of the Pacific and North American plates in addition to interplate events. We postulate that the Kasatochi seismic swarm was a manifestation of the complex interaction of tectonic and magmatic processes in the Earth's crust. Although magmatic intrusion triggered the earthquakes in the swarm, the earthquakes failed in context of the regional stress field.

  12. Mechanism of the 1996-97 non-eruptive volcano-tectonic earthquake swarm at Iliamna Volcano, Alaska

    Science.gov (United States)

    Roman, D.C.; Power, J.A.

    2011-01-01

    A significant number of volcano-tectonic(VT) earthquake swarms, some of which are accompanied by ground deformation and/or volcanic gas emissions, do not culminate in an eruption.These swarms are often thought to represent stalled intrusions of magma into the mid- or shallow-level crust.Real-time assessment of the likelihood that a VTswarm will culminate in an eruption is one of the key challenges of volcano monitoring, and retrospective analysis of non-eruptive swarms provides an important framework for future assessments. Here we explore models for a non-eruptive VT earthquake swarm located beneath Iliamna Volcano, Alaska, in May 1996-June 1997 through calculation and inversion of fault-plane solutions for swarm and background periods, and through Coulomb stress modeling of faulting types and hypocenter locations observed during the swarm. Through a comparison of models of deep and shallow intrusions to swarm observations,we aim to test the hypothesis that the 1996-97 swarm represented a shallow intrusion, or "failed" eruption.Observations of the 1996-97 swarm are found to be consistent with several scenarios including both shallow and deep intrusion, most likely involving a relatively small volume of intruded magma and/or a low degree of magma pressurization corresponding to a relatively low likelihood of eruption. ?? 2011 Springer-Verlag.

  13. Application of Earthquake Subspace Detectors at Kilauea and Mauna Loa Volcanoes, Hawai`i

    Science.gov (United States)

    Okubo, P.; Benz, H.; Yeck, W.

    2016-12-01

    Recent studies have demonstrated the capabilities of earthquake subspace detectors for detailed cataloging and tracking of seismicity in a number of regions and settings. We are exploring the application of subspace detectors at the United States Geological Survey's Hawaiian Volcano Observatory (HVO) to analyze seismicity at Kilauea and Mauna Loa volcanoes. Elevated levels of microseismicity and occasional swarms of earthquakes associated with active volcanism here present cataloging challenges due the sheer numbers of earthquakes and an intrinsically low signal-to-noise environment featuring oceanic microseism and volcanic tremor in the ambient seismic background. With high-quality continuous recording of seismic data at HVO, we apply subspace detectors (Harris and Dodge, 2011, Bull. Seismol. Soc. Am., doi: 10.1785/0120100103) during intervals of noteworthy seismicity. Waveform templates are drawn from Magnitude 2 and larger earthquakes within clusters of earthquakes cataloged in the HVO seismic database. At Kilauea, we focus on seismic swarms in the summit caldera region where, despite continuing eruptions from vents in the summit region and in the east rift zone, geodetic measurements reflect a relatively inflated volcanic state. We also focus on seismicity beneath and adjacent to Mauna Loa's summit caldera that appears to be associated with geodetic expressions of gradual volcanic inflation, and where precursory seismicity clustered prior to both Mauna Loa's most recent eruptions in 1975 and 1984. We recover several times more earthquakes with the subspace detectors - down to roughly 2 magnitude units below the templates, based on relative amplitudes - compared to the numbers of cataloged earthquakes. The increased numbers of detected earthquakes in these clusters, and the ability to associate and locate them, allow us to infer details of the spatial and temporal distributions and possible variations in stresses within these key regions of the volcanoes.

  14. Micro-earthquake signal analysis and hypocenter determination around Lokon volcano complex

    Energy Technology Data Exchange (ETDEWEB)

    Firmansyah, Rizky, E-mail: rizkyfirmansyah@hotmail.com [Geophysical Engineering, Faculty of Mining and Petroleum Engineering, Institut Teknologi Bandung, Bandung, 40132 (Indonesia); Nugraha, Andri Dian, E-mail: nugraha@gf.itb.ac.id [Global Geophysical Group, Faculty of Mining and Petroleum Engineering, Institut Teknologi Bandung, Bandung, 40132 (Indonesia); Kristianto, E-mail: kris@vsi.esdm.go.id [Center for Volcanology and Geological Hazard Mitigation (CVGHM), Geological Agency, Bandung, 40122 (Indonesia)

    2015-04-24

    Mount Lokon is one of five active volcanoes which is located in the North Sulawesi region. Since June 26{sup th}, 2011, standby alert set by the Center for Volcanology and Geological Hazard Mitigation (CVGHM) for this mountain. The Mount Lokon volcano erupted on July 4{sup th}, 2011 and still continuously erupted until August 28{sup th}, 2011. Due to its high seismic activity, this study is focused to analysis of micro-earthquake signal and determine the micro-earthquake hypocenter location around the complex area of Lokon-Empung Volcano before eruption phase in 2011 (time periods of January, 2009 up to March, 2010). Determination of the hypocenter location was conducted with Geiger Adaptive Damping (GAD) method. We used initial model from previous study in Volcan de Colima, Mexico. The reason behind the model selection was based on the same characteristics that shared between Mount Lokon and Colima including andesitic stratovolcano and small-plinian explosions volcanian types. In this study, a picking events was limited to the volcano-tectonics of A and B types, hybrid, long-period that has a clear signal onset, and local tectonic with different maximum S – P time are not more than three seconds. As a result, we observed the micro-earthquakes occurred in the area north-west of Mount Lokon region.

  15. Micro-earthquake signal analysis and hypocenter determination around Lokon volcano complex

    International Nuclear Information System (INIS)

    Firmansyah, Rizky; Nugraha, Andri Dian; Kristianto

    2015-01-01

    Mount Lokon is one of five active volcanoes which is located in the North Sulawesi region. Since June 26 th , 2011, standby alert set by the Center for Volcanology and Geological Hazard Mitigation (CVGHM) for this mountain. The Mount Lokon volcano erupted on July 4 th , 2011 and still continuously erupted until August 28 th , 2011. Due to its high seismic activity, this study is focused to analysis of micro-earthquake signal and determine the micro-earthquake hypocenter location around the complex area of Lokon-Empung Volcano before eruption phase in 2011 (time periods of January, 2009 up to March, 2010). Determination of the hypocenter location was conducted with Geiger Adaptive Damping (GAD) method. We used initial model from previous study in Volcan de Colima, Mexico. The reason behind the model selection was based on the same characteristics that shared between Mount Lokon and Colima including andesitic stratovolcano and small-plinian explosions volcanian types. In this study, a picking events was limited to the volcano-tectonics of A and B types, hybrid, long-period that has a clear signal onset, and local tectonic with different maximum S – P time are not more than three seconds. As a result, we observed the micro-earthquakes occurred in the area north-west of Mount Lokon region

  16. Hydrothermal response to a volcano-tectonic earthquake swarm, Lassen, California

    Science.gov (United States)

    Ingebritsen, Steven E.; Shelly, David R.; Hsieh, Paul A.; Clor, Laura; P.H. Seward,; Evans, William C.

    2015-01-01

    The increasing capability of seismic, geodetic, and hydrothermal observation networks allows recognition of volcanic unrest that could previously have gone undetected, creating an imperative to diagnose and interpret unrest episodes. A November 2014 earthquake swarm near Lassen Volcanic National Park, California, which included the largest earthquake in the area in more than 60 years, was accompanied by a rarely observed outburst of hydrothermal fluids. Although the earthquake swarm likely reflects upward migration of endogenous H2O-CO2 fluids in the source region, there is no evidence that such fluids emerged at the surface. Instead, shaking from the modest sized (moment magnitude 3.85) but proximal earthquake caused near-vent permeability increases that triggered increased outflow of hydrothermal fluids already present and equilibrated in a local hydrothermal aquifer. Long-term, multiparametric monitoring at Lassen and other well-instrumented volcanoes enhances interpretation of unrest and can provide a basis for detailed physical modeling.

  17. A distal earthquake cluster concurrent with the 2006 explosive eruption of Augustine Volcano, Alaska

    Science.gov (United States)

    Fisher, M.A.; Ruppert, N.A.; White, R.A.; Wilson, Frederic H.; Comer, D.; Sliter, R.W.; Wong, F.L.

    2009-01-01

    Clustered earthquakes located 25??km northeast of Augustine Volcano began about 6??months before and ceased soon after the volcano's 2006 explosive eruption. This distal seismicity formed a dense cluster less than 5??km across, in map view, and located in depth between 11??km and 16??km. This seismicity was contemporaneous with sharply increased shallow earthquake activity directly below the volcano's vent. Focal mechanisms for five events within the distal cluster show strike-slip fault movement. Cluster seismicity best defines a plane when it is projected onto a northeast-southwest cross section, suggesting that the seismogenic fault strikes northwest. However, two major structural trends intersect near Augustine Volcano, making it difficult to put the seismogenic fault into a regional-geologic context. Specifically, interpretation of marine multichannel seismic-reflection (MCS) data shows reverse faults, directly above the seismicity cluster, that trend northeast, parallel to the regional geologic strike but perpendicular to the fault suggested by the clustered seismicity. The seismogenic fault could be a reactivated basement structure.

  18. Use of high resolution satellite images for monitoring of earthquakes and volcano activity.

    Science.gov (United States)

    Arellano-Baeza, Alonso A.

    Our studies have shown that the strain energy accumulation deep in the Earth's crust that precedes a strong earthquake can be detected by applying a lineament extraction technique to the high-resolution multispectral satellite images. A lineament is a straight or a somewhat curved feature in a satellite image, which it is possible to detect by a special processing of images based on directional filtering and or Hough transform. We analyzed tens of earthquakes occurred in the Pacific coast of the South America with the Richter scale magnitude ˜4.5, using ASTER/TERRA multispectral satellite images for detection and analysis of changes in the system of lineaments previous to a strong earthquake. All events were located in the regions with small seasonal variations and limited vegetation to facilitate the tracking of features associated with the seismic activity only. It was found that the number and orientation of lineaments changed significantly about one month before an earthquake approximately, and a few months later the system returns to its initial state. This effect increases with the earthquake magnitude. It also was shown that the behavior of lineaments associated to the volcano seismic activity is opposite to that obtained previously for earthquakes. This discrepancy can be explained assuming that in the last case the main reason of earthquakes is compression and accumulation of strength in the Earth's crust due to subduction of tectonic plates, whereas in the first case we deal with the inflation of a volcano edifice due to elevation of pressure and magma intrusion. The results obtained made it possible to include this research as a part of scientific program of Chilean Remote Sensing Satellite mission to be launched in 2010.

  19. Earthquake prediction using extinct monogenetic volcanoes: A possible new research strategy

    Science.gov (United States)

    Szakács, Alexandru

    2011-04-01

    Volcanoes are extremely effective transmitters of matter, energy and information from the deep Earth towards its surface. Their capacities as information carriers are far to be fully exploited so far. Volcanic conduits can be viewed in general as rod-like or sheet-like vertical features with relatively homogenous composition and structure crosscutting geological structures of far more complexity and compositional heterogeneity. Information-carrying signals such as earthquake precursor signals originating deep below the Earth surface are transmitted with much less loss of information through homogenous vertically extended structures than through the horizontally segmented heterogeneous lithosphere or crust. Volcanic conduits can thus be viewed as upside-down "antennas" or waveguides which can be used as privileged pathways of any possible earthquake precursor signal. In particular, conduits of monogenetic volcanoes are promising transmitters of deep Earth information to be received and decoded at surface monitoring stations because the expected more homogenous nature of their rock-fill as compared to polygenetic volcanoes. Among monogenetic volcanoes those with dominantly effusive activity appear as the best candidates for privileged earthquake monitoring sites. In more details, effusive monogenetic volcanic conduits filled with rocks of primitive parental magma composition indicating direct ascent from sub-lithospheric magma-generating areas are the most suitable. Further selection criteria may include age of the volcanism considered and the presence of mantle xenoliths in surface volcanic products indicating direct and straightforward link between the deep lithospheric mantle and surface through the conduit. Innovative earthquake prediction research strategies can be based and developed on these grounds by considering conduits of selected extinct monogenetic volcanoes and deep trans-crustal fractures as privileged emplacement sites of seismic monitoring stations

  20. Improve earthquake hypocenter using adaptive simulated annealing inversion in regional tectonic, volcano tectonic, and geothermal observation

    Energy Technology Data Exchange (ETDEWEB)

    Ry, Rexha Verdhora, E-mail: rexha.vry@gmail.com [Master Program of Geophysical Engineering, Faculty of Mining and Petroleum Engineering, Institut Teknologi Bandung, Jalan Ganesha No.10, Bandung 40132 (Indonesia); Nugraha, Andri Dian, E-mail: nugraha@gf.itb.ac.id [Global Geophysical Research Group, Faculty of Mining and Petroleum Engineering, Institut Teknologi Bandung, Jalan Ganesha No.10, Bandung 40132 (Indonesia)

    2015-04-24

    Observation of earthquakes is routinely used widely in tectonic activity observation, and also in local scale such as volcano tectonic and geothermal activity observation. It is necessary for determining the location of precise hypocenter which the process involves finding a hypocenter location that has minimum error between the observed and the calculated travel times. When solving this nonlinear inverse problem, simulated annealing inversion method can be applied to such global optimization problems, which the convergence of its solution is independent of the initial model. In this study, we developed own program codeby applying adaptive simulated annealing inversion in Matlab environment. We applied this method to determine earthquake hypocenter using several data cases which are regional tectonic, volcano tectonic, and geothermal field. The travel times were calculated using ray tracing shooting method. We then compared its results with the results using Geiger’s method to analyze its reliability. Our results show hypocenter location has smaller RMS error compared to the Geiger’s result that can be statistically associated with better solution. The hypocenter of earthquakes also well correlated with geological structure in the study area. Werecommend using adaptive simulated annealing inversion to relocate hypocenter location in purpose to get precise and accurate earthquake location.

  1. Earthquakes and Volcanic Processes at San Miguel Volcano, El Salvador, Determined from a Small, Temporary Seismic Network

    Science.gov (United States)

    Hernandez, S.; Schiek, C. G.; Zeiler, C. P.; Velasco, A. A.; Hurtado, J. M.

    2008-12-01

    The San Miguel volcano lies within the Central American volcanic chain in eastern El Salvador. The volcano has experienced at least 29 eruptions with Volcano Explosivity Index (VEI) of 2. Since 1970, however, eruptions have decreased in intensity to an average of VEI 1, with the most recent eruption occurring in 2002. Eruptions at San Miguel volcano consist mostly of central vent and phreatic eruptions. A critical challenge related to the explosive nature of this volcano is to understand the relationships between precursory surface deformation, earthquake activity, and volcanic activity. In this project, we seek to determine sub-surface structures within and near the volcano, relate the local deformation to these structures, and better understand the hazard that the volcano presents in the region. To accomplish these goals, we deployed a six station, broadband seismic network around San Miguel volcano in collaboration with researchers from Servicio Nacional de Estudios Territoriales (SNET). This network operated continuously from 23 March 2007 to 15 January 2008 and had a high data recovery rate. The data were processed to determine earthquake locations, magnitudes, and, for some of the larger events, focal mechanisms. We obtained high precision locations using a double-difference approach and identified at least 25 events near the volcano. Ongoing analysis will seek to identify earthquake types (e.g., long period, tectonic, and hybrid events) that occurred in the vicinity of San Miguel volcano. These results will be combined with radar interferometric measurements of surface deformation in order to determine the relationship between surface and subsurface processes at the volcano.

  2. Volcano-tectonic earthquakes: A new tool for estimating intrusive volumes and forecasting eruptions

    Science.gov (United States)

    White, Randall A.; McCausland, Wendy

    2016-01-01

    We present data on 136 high-frequency earthquakes and swarms, termed volcano-tectonic (VT) seismicity, which preceded 111 eruptions at 83 volcanoes, plus data on VT swarms that preceded intrusions at 21 other volcanoes. We find that VT seismicity is usually the earliest reported seismic precursor for eruptions at volcanoes that have been dormant for decades or more, and precedes eruptions of all magma types from basaltic to rhyolitic and all explosivities from VEI 0 to ultraplinian VEI 6 at such previously long-dormant volcanoes. Because large eruptions occur most commonly during resumption of activity at long-dormant volcanoes, VT seismicity is an important precursor for the Earth's most dangerous eruptions. VT seismicity precedes all explosive eruptions of VEI ≥ 5 and most if not all VEI 4 eruptions in our data set. Surprisingly we find that the VT seismicity originates at distal locations on tectonic fault structures at distances of one or two to tens of kilometers laterally from the site of the eventual eruption, and rarely if ever starts beneath the eruption site itself. The distal VT swarms generally occur at depths almost equal to the horizontal distance of the swarm from the summit out to about 15 km distance, beyond which hypocenter depths level out. We summarize several important characteristics of this distal VT seismicity including: swarm-like nature, onset days to years prior to the beginning of magmatic eruptions, peaking of activity at the time of the initial eruption whether phreatic or magmatic, and large non-double couple component to focal mechanisms. Most importantly we show that the intruded magma volume can be simply estimated from the cumulative seismic moment of the VT seismicity from:

  3. Earthquake and volcano hazard notices: An economic evaluation of changes in risk perceptions

    Science.gov (United States)

    Bernknopf, R.L.; Brookshire, D.S.; Thayer, M.A.

    1990-01-01

    Earthquake and volcano hazard notices were issued for the Mammoth Lakes, California area by the U.S. Geological Survey under the authority granted by the Disaster Relief Act of 1974. The effects on investment, recretion visitation, and risk perceptionsare explored. The hazard notices did not affect recreation visitation, although investment was affected. A perceived loss in the market value of homes was documented. Risk perceptions were altered for property owners. Communication of the probability of an event over time would enhance hazard notices as a policy instrument and would mitigate unnecessary market perturbations. ?? 1990.

  4. Impact- and earthquake- proof roof structure

    International Nuclear Information System (INIS)

    Shohara, Ryoichi.

    1990-01-01

    Building roofs are constituted with roof slabs, an earthquake proof layer at the upper surface thereof and an impact proof layer made of iron-reinforced concrete disposed further thereover. Since the roofs constitute an earthquake proof structure loading building dampers on the upper surface of the slabs by the concrete layer, seismic inputs of earthquakes to the buildings can be moderated and the impact-proof layer is formed, to ensure the safety to external conditions such as earthquakes or falling accidents of airplane in important facilities such as reactor buildings. (T.M.)

  5. Special issue: Terrestrial fluids, earthquakes and volcanoes: The Hiroshi Wakita volume I

    Science.gov (United States)

    Perez, Nemesio M.; King, Chi-Yu; Gurrieri, Sergio; McGee, Kenneth A.

    2006-01-01

    Terrestrial Fluids, Earthquakes and Volcanoes: The Hiroshi Wakita Volume I is a special publication to honor Professor Hiroshi Wakita for his scientific contributions. This volume consists of 17 original papers dealing with various aspects of the role of terrestrial fluids in earthquake and volcanic processes, which reflect Prof. Wakita’s wide scope of research interests.Professor Wakita co-founded the Laboratory for Earthquake Chemistry in 1978 and served as its director from 1988 until his retirement from the university in 1997. He has made the laboratory a leading world center for studying earthquakes and volcanic activities by means of geochemical and hydrological methods. Together with his research team and a number of foreign guest researchers that he attracted, he has made many significant contributions in the above-mentioned scientific fields of interest. This achievement is a testimony to not only his scientific talent, but also his enthusiasm, his open mindedness, and his drive in obtaining both human and financial support.

  6. Relaxation of the south flank after the 7.2-magnitude Kalapana earthquake, Kilauea Volcano, Hawaii

    Science.gov (United States)

    Dvorak, John J.; Klein, Fred W.; Swanson, Donald A.

    1994-01-01

    An M = 7.2 earthquake on 29 November 1975 caused the south flank of Kilauea Volcano, Hawaii, to move seaward several meters: a catastrophic release of compression of the south flank caused by earlier injections of magma into the adjacent segment of a rift zone. The focal mechanisms of the mainshock, the largest foreshock, and the largest aftershock suggest seaward movement of the upper block. The rate of aftershocks decreased in a familiar hyperbolic decay, reaching the pre-1975 rate of seismicity by the mid-1980s. Repeated rift-zone intrusions and eruptions after 1975, which occurred within 25 km of the summit area, compressed the adjacent portion of the south flank, apparently masking continued seaward displacement of the south flank. This is evident along a trilateration line that continued to extend, suggesting seaward displacement, immediately after the M = 7.2 earthquake, but then was compressed during a series of intrusions and eruptions that began in September 1977. Farther to the east, trilateration measurements show that the portion of the south flank above the aftershock zone, but beyond the area of compression caused by the rift-zone intrusions and eruptions, continued to move seaward at a decreasing rate until the mid-1980s, mimicking the decay in aftershock rate. Along the same portion of the south flank, the pattern of vertical surface displacements can be explained by continued seaward movement of the south flank and development of two eruptive fissures along the east rift zone, each of which extended from a depth of ∼3 km to the surface. The aftershock rate and continued seaward movement of the south flank are reminiscent of crustal response to other large earthquakes, such as the 1966 M = 6 Parkfield earthquake and the 1983 M = 6.5 Coalinga earthquake.

  7. Volcano-tectonic earthquakes: A new tool for estimating intrusive volumes and forecasting eruptions

    Science.gov (United States)

    White, Randall; McCausland, Wendy

    2016-01-01

    We present data on 136 high-frequency earthquakes and swarms, termed volcano-tectonic (VT) seismicity, which preceded 111 eruptions at 83 volcanoes, plus data on VT swarms that preceded intrusions at 21 other volcanoes. We find that VT seismicity is usually the earliest reported seismic precursor for eruptions at volcanoes that have been dormant for decades or more, and precedes eruptions of all magma types from basaltic to rhyolitic and all explosivities from VEI 0 to ultraplinian VEI 6 at such previously long-dormant volcanoes. Because large eruptions occur most commonly during resumption of activity at long-dormant volcanoes, VT seismicity is an important precursor for the Earth's most dangerous eruptions. VT seismicity precedes all explosive eruptions of VEI ≥ 5 and most if not all VEI 4 eruptions in our data set. Surprisingly we find that the VT seismicity originates at distal locations on tectonic fault structures at distances of one or two to tens of kilometers laterally from the site of the eventual eruption, and rarely if ever starts beneath the eruption site itself. The distal VT swarms generally occur at depths almost equal to the horizontal distance of the swarm from the summit out to about 15 km distance, beyond which hypocenter depths level out. We summarize several important characteristics of this distal VT seismicity including: swarm-like nature, onset days to years prior to the beginning of magmatic eruptions, peaking of activity at the time of the initial eruption whether phreatic or magmatic, and large non-double couple component to focal mechanisms. Most importantly we show that the intruded magma volume can be simply estimated from the cumulative seismic moment of the VT seismicity from: Log10 V = 0.77 Log ΣMoment - 5.32, with volume, V, in cubic meters and seismic moment in Newton meters. Because the cumulative seismic moment can be approximated from the size of just the few largest events, and is quite insensitive to precise locations

  8. Mechanical coupling between earthquakes and volcanoes inferred from stress transfer models: evidence from Vesuvio, Etna and Alban Hills (Italy)

    Science.gov (United States)

    Cocco, M.; Feuillet, N.; Nostro, C.; Musumeci, C.

    2003-04-01

    We investigate the mechanical interactions between tectonic faults and volcanic sources through elastic stress transfer and discuss the results of several applications to Italian active volcanoes. We first present the stress modeling results that point out a two-way coupling between Vesuvius eruptions and historical earthquakes in Southern Apennines, which allow us to provide a physical interpretation of their statistical correlation. Therefore, we explore the elastic stress interaction between historical eruptions at the Etna volcano and the largest earthquakes in Eastern Sicily and Calabria. We show that the large 1693 seismic event caused an increase of compressive stress along the rift zone, which can be associated to the lack of flank eruptions of the Etna volcano for about 70 years after the earthquake. Moreover, the largest Etna eruptions preceded by few decades the large 1693 seismic event. Our modeling results clearly suggest that all these catastrophic events are tectonically coupled. We also investigate the effect of elastic stress perturbations on the instrumental seismicity caused by magma inflation at depth both at the Etna and at the Alban Hills volcanoes. In particular, we model the seismicity pattern at the Alban Hills volcano (central Italy) during a seismic swarm occurred in 1989-90 and we interpret it in terms of Coulomb stress changes caused by magmatic processes in an extensional tectonic stress field. We verify that the earthquakes occur in areas of Coulomb stress increase and that their faulting mechanisms are consistent with the stress perturbation induced by the volcanic source. Our results suggest a link between faults and volcanic sources, which we interpret as a tectonic coupling explaining the seismicity in a large area surrounding the volcanoes.

  9. Near-real time 3D probabilistic earthquakes locations at Mt. Etna volcano

    Science.gov (United States)

    Barberi, G.; D'Agostino, M.; Mostaccio, A.; Patane', D.; Tuve', T.

    2012-04-01

    Automatic procedure for locating earthquake in quasi-real time must provide a good estimation of earthquakes location within a few seconds after the event is first detected and is strongly needed for seismic warning system. The reliability of an automatic location algorithm is influenced by several factors such as errors in picking seismic phases, network geometry, and velocity model uncertainties. On Mt. Etna, the seismic network is managed by INGV and the quasi-real time earthquakes locations are performed by using an automatic-picking algorithm based on short-term-average to long-term-average ratios (STA/LTA) calculated from an approximate squared envelope function of the seismogram, which furnish a list of P-wave arrival times, and the location algorithm Hypoellipse, with a 1D velocity model. The main purpose of this work is to investigate the performances of a different automatic procedure to improve the quasi-real time earthquakes locations. In fact, as the automatic data processing may be affected by outliers (wrong picks), the use of a traditional earthquake location techniques based on a least-square misfit function (L2-norm) often yield unstable and unreliable solutions. Moreover, on Mt. Etna, the 1D model is often unable to represent the complex structure of the volcano (in particular the strong lateral heterogeneities), whereas the increasing accuracy in the 3D velocity models at Mt. Etna during recent years allows their use today in routine earthquake locations. Therefore, we selected, as reference locations, all the events occurred on Mt. Etna in the last year (2011) which was automatically detected and located by means of the Hypoellipse code. By using this dataset (more than 300 events), we applied a nonlinear probabilistic earthquake location algorithm using the Equal Differential Time (EDT) likelihood function, (Font et al., 2004; Lomax, 2005) which is much more robust in the presence of outliers in the data. Successively, by using a probabilistic

  10. Protection of the human race against natural hazards (asteroids, comets, volcanoes, earthquakes)

    Science.gov (United States)

    Smith, Joseph V.

    1985-10-01

    Although we justifiably worry about the danger of nuclear war to civilization, and perhaps even to survival of the human race, we tend to consider natural hazards (e.g., comets, asteroids, volcanoes, earthquakes) as unavoidable acts of God. In any human lifetime, a truly catastrophic natural event is very unlikely, but ultimately one will occur. For the first time in human history we have sufficient technical skills to begin protection of Earth from some natural hazards. We could decide collectively throughout the world to reassign resources: in particular, reduction of nuclear and conventional weapons to a less dangerous level would allow concomitant increase of international programs for detection and prevention of natural hazards. Worldwide cooperation to mitigate natural hazards might help psychologically to lead us away from the divisive bickering that triggers wars. Future generations could hail us as pioneers of peace and safety rather than curse us as agents of death and destruction.

  11. Napa Earthquake impact on water systems

    Science.gov (United States)

    Wang, J.

    2014-12-01

    South Napa earthquake occurred in Napa, California on August 24 at 3am, local time, and the magnitude is 6.0. The earthquake was the largest in SF Bay Area since the 1989 Loma Prieta earthquake. Economic loss topped $ 1 billion. Wine makers cleaning up and estimated the damage on tourism. Around 15,000 cases of lovely cabernet were pouring into the garden at the Hess Collection. Earthquake potentially raise water pollution risks, could cause water crisis. CA suffered water shortage recent years, and it could be helpful on how to prevent underground/surface water pollution from earthquake. This research gives a clear view on drinking water system in CA, pollution on river systems, as well as estimation on earthquake impact on water supply. The Sacramento-San Joaquin River delta (close to Napa), is the center of the state's water distribution system, delivering fresh water to more than 25 million residents and 3 million acres of farmland. Delta water conveyed through a network of levees is crucial to Southern California. The drought has significantly curtailed water export, and salt water intrusion reduced fresh water outflows. Strong shaking from a nearby earthquake can cause saturated, loose, sandy soils liquefaction, and could potentially damage major delta levee systems near Napa. Napa earthquake is a wake-up call for Southern California. It could potentially damage freshwater supply system.

  12. Correlations of volcanic ash texture with explosion earthquakes from vulcanian eruptions at Sakurajima volcano, Japan

    Science.gov (United States)

    Miwa, T.; Toramaru, A.; Iguchi, M.

    2009-07-01

    We compare the texture of volcanic ash with the maximum amplitude of explosion earthquakes ( Aeq) for vulcanian eruptions from Sakurajima volcano. We analyze the volcanic ash emitted by 17 vulcanian eruptions from 1974 to 1987. Using a stereoscopic microscope, we classify the glassy particles into smooth surface particles (S-type particles) and non-smooth surface particles (NS-type particles) according to their surface conditions—gloss or non-gloss appearance—as an indicator of the freshness of the particles. S-type particles are further classified into V-type particles (those including vesicles) and NV-type particles (those without vesicles) by means of examinations under a polarized microscopic of polished thin sections. Cross-correlated examinations against seismological data show that: 1) the number fraction of S-type particles (S-fraction) has a positive correlation with Aeq, 2) the number ratio of NV-type particles to V-type particles (the N/V number ratio) has a positive correlation with Aeq, and 3) for explosions accompanied with BL-type earthquake swarms, the N/V number ratio has a negative correlation with the duration of the BL-Swarms. BL-Swarms refer to the phenomenon of numerous BL-type earthquakes occurring within a few days, prior to an increase in explosive activity [Kamo, K., 1978. Some phenomena before the summit crater eruptions at Sakura-zima volcano. Bull. Volcanol. Soc. Japan., 23, 53-64]. The positive correlation between the N/V number ratio and Aeq could indicate that a large amount of separated gas from fresh magma results in a large Aeq. Plagioclase microlite textual analysis of NV-type particles from five explosive events without BL-Swarms shows that the plagioclase microlite number density (MND) and the L/ W (length/width) ratio have a positive correlation with Aeq. A comparison between textural data (MND, L/ W ratio, crystallinity) and the result of a decompression-induced crystallization experiment [Couch, S., Sparks, R

  13. Earthquake occurrence reveals magma ascent beneath volcanoes and seamounts in the Banda Region

    Czech Academy of Sciences Publication Activity Database

    Špičák, Aleš; Kuna, Václav; Vaněk, Jiří

    2013-01-01

    Roč. 75, č. 777 (2013), 777/1-777/8 ISSN 0258-8900 R&D Projects: GA MŠk ME09011 Institutional support: RVO:67985530 Keywords : Banda region * global seismological data * earthquake swarm Subject RIV: DC - Siesmology, Volcanology, Earth Structure Impact factor: 2.667, year: 2013

  14. A Seismological Portrait of the Anomalous 1996 Bardarbunga Volcano, Iceland, Earthquake (Invited)

    Science.gov (United States)

    Tkalcic, H.; Dreger, D. S.; Foulger, G. R.; Julian, B. R.; Fichtner, A.

    2009-12-01

    The Bardarbunga volcano lies beneath the 500-m-thick Vatnajokull icecap, the largest glacier in Europe. Earthquakes with atypical seismic radiation have occurred beneath the Bardarbunga caldera and have been routinely reported in the Global CMT catalog. An earthquake with Mw 5.6 and a strong non-double-couple (NDC) radiation pattern occurred beneath the caldera on 29 September, 1996. A peculiarity of that earthquake was that it was the first in a sequence of seismic and magmatic events and that it was followed, not preceded or accompanied, by a major eruption which ultimately led to a breakout flood from the subglacial caldera lake. The earthquake was recorded well by the regional-scale Iceland Hotspot Project seismic experiment. One of the proposed hypotheses to explain the observed displacements and the sequence of events was the inflation of a shallow magma chamber that might have caused rupture on ring faults below the chamber. Iceland has a heterogeneous crust, with variable thickness, and thus a 1D structural model is not ideal for waveform modeling. We investigated the earthquake with a point-source complete moment-tensor (MT) inversion method using regional long-period seismic waveforms and a composite structural model of Iceland based on joint modeling of teleseismic receiver functions and surface-wave dispersion. When such a model is used, the waveform modeling yields a NDC solution with a strong, vertically oriented compensated linear vector dipole component and a statistically insignificant volumetric contraction. The absence of a volumetric component is surprising in the case of a large volcanic earthquake that cannot be explained by shear slip on a planar fault. A possible mechanism that can produce an earthquake without a volumetric component involves two offset sources with similar but opposite volume changes. We show that although such a model cannot be ruled out, it is unlikely. In order to investigate the hypothesis of a rupture occurring on a

  15. Using remote sensing to predict earthquake impacts

    Science.gov (United States)

    Fylaktos, Asimakis; Yfantidou, Anastasia

    2017-09-01

    Natural hazards like earthquakes can result to enormous property damage, and human casualties in mountainous areas. Italy has always been exposed to numerous earthquakes, mostly concentrated in central and southern regions. Last year, two seismic events near Norcia (central Italy) have occurred, which led to substantial loss of life and extensive damage to properties, infrastructure and cultural heritage. This research utilizes remote sensing products and GIS software, to provide a database of information. We used both SAR images of Sentinel 1A and optical imagery of Landsat 8 to examine the differences of topography with the aid of the multi temporal monitoring technique. This technique suits for the observation of any surface deformation. This database is a cluster of information regarding the consequences of the earthquakes in groups, such as property and infrastructure damage, regional rifts, cultivation loss, landslides and surface deformations amongst others, all mapped on GIS software. Relevant organizations can implement these data in order to calculate the financial impact of these types of earthquakes. In the future, we can enrich this database including more regions and enhance the variety of its applications. For instance, we could predict the future impacts of any type of earthquake in several areas, and design a preliminarily model of emergency for immediate evacuation and quick recovery response. It is important to know how the surface moves, in particular geographical regions like Italy, Cyprus and Greece, where earthquakes are so frequent. We are not able to predict earthquakes, but using data from this research, we may assess the damage that could be caused in the future.

  16. About swarms of long-period earthquakes at volcano Nyamuragira of the Virunga region, Western Rift Valley of Africa (D.R. Congo

    Directory of Open Access Journals (Sweden)

    Rusangiza B.K.

    2012-01-01

    Full Text Available Swarms of Long Period earthquakes generated by the Nyamuragira volcano for the period from January 2000 to November 2006 before 21 January 2000, 5 February 2001, 25 July 2002, 8 May 2004 and 27 November 2006 Nyamuragira eruptions have been analyzed. Interest is focused on the frequency distribution of these earthquakes and on the variation of the m-value of observed earthquake swarms. It is found that m-values which generally vary between 0.9 and 1.6, and shifts towards larger values of 1.7 to 3.23 two to four months prior to eruptions of the volcano.

  17. Crustal CO2 liberation during the 2006 eruption and earthquake events at Merapi volcano, Indonesia

    Science.gov (United States)

    Troll, Valentin R.; Hilton, David R.; Jolis, Ester M.; Chadwick, Jane P.; Blythe, Lara S.; Deegan, Frances M.; Schwarzkopf, Lothar M.; Zimmer, Martin

    2012-06-01

    High-temperature volcanic gas is widely considered to originate from ascending, mantle-derived magma. In volcanic arc systems, crustal inputs to magmatic gases mainly occur via subducted sediments in the mantle source region. Our data from Merapi volcano, Indonesia imply, however, that during the April-October 2006 eruption significant quantities of CO2 were added from shallow crustal sources. We show that prior to the 2006 events, summit fumarole gas δ13C(CO2) is virtually constant (δ13C1994-2005 = -4.1 ± 0.3‰), but during the 2006 eruption and after the shallow Yogyakarta earthquake of late May, 2006 (M6.4; hypocentres at 10-15 km depth), carbon isotope ratios increased to -2.4 ± 0.2‰. This rise in δ13C is consistent with considerable addition of crustal CO2 and coincided with an increase in eruptive intensity by a factor of ˜3 to 5. We postulate that this shallow crustal volatile input supplemented the mantle-derived volatile flux at Merapi, intensifying and sustaining the 2006 eruption. Late-stage volatile additions from crustal contamination may thus provide a trigger for explosive eruptions independently of conventional magmatic processes.

  18. The story of the Hawaiian Volcano Observatory -- A remarkable first 100 years of tracking eruptions and earthquakes

    Science.gov (United States)

    Babb, Janet L.; Kauahikaua, James P.; Tilling, Robert I.

    2011-01-01

    part of the USGS, the Nation’s premier Earth science agency. It currently operates under the direction of the USGS Volcano Science Center, which now supports five volcano observatories covering six U.S. areas—Hawaiʻi (HVO), Alaska and the Northern Mariana Islands (Alaska Volcano Observatory), Washington and Oregon (Cascades Volcano Observatory), California (California Volcano Observatory), and the Yellowstone region (Yellowstone Volcano Observatory). Although the National Park Service (NPS) managed HVO for only 12 years, HVO has enjoyed a close working relationship with Hawaiʻi Volcanoes National Park (named Hawaii National Park until 1961) since the park’s founding in 1916. Today, as in past years, the USGS and NPS work together to ensure the safety and education of park visitors. We are grateful to all park employees, particularly Superintendent Cindy Orlando and Chief Ranger Talmadge Magno and their predecessors, for their continuing support of HVO’s mission. HVO also works closely with the Hawaiʻi County Civil Defense. During volcanic and earthquake crises, we have appreciated the support of civil defense staff, especially that of Harry Kim and Quince Mento, who administered the agency during highly stressful episodes of Kīlauea's ongoing eruption. Our work in remote areas on Hawaiʻi’s active volcanoes is possible only with the able assistance of Hawaiʻi County and private pilots who have safely flown HVO staff to eruption sites through the decades. A special mahalo goes to David Okita, who has been HVO’s principal helicopter pilot for more than two decades. Many commercial and Civil Air Patrol pilots have also assisted HVO by reporting their observations during various eruptive events. Hawaiʻi’s news media—print, television, radio, and online sources—do an excellent job of distributing volcano and earthquake information to the public. Their assistance is invaluable to HVO, especially during times of crisis. HVO’s efforts to provide

  19. Anomalous Diffuse CO2 Emission Changes at San Vicente Volcano Related to Earthquakes in El Salvador, Central America

    Science.gov (United States)

    Salazar, J.; Hernandez, P.; Perez, N.; Barahona, F.; Olmos, R.; Cartagena, R.; Soriano, T.; Notsu, K.; Lopez, D.

    2001-12-01

    San Vicente or Chichontepeque (2,180 m a.s.l.) is a composite andesitic volcano located 50 Km east of San Salvador. Its paired edifice rises from the so-called Central Graben, an extensional structure parallel to the Pacific coast, and has been inactive for the last 3000 yrs. Fumaroles (98.2°C ) and hot spring waters are present along radial faults at two localities on the northern slope of the volcano (Aguas Agrias and El Infiernillo). CO2 is the most abundant component in the dry gas (>90%) and its mean isotopic composition (δ 13C(CO2)=-2.11 ‰ and 3He/4He of 6.9 Ra) suggests a magmatic origin for the CO2. These manifestations are supposed to be linked to a 1,200 m depth 250°C reservoir with a CO2 partial pressure of 14 bar extended beneath the volcano (Aiuppa et al., 1997). In February 13, 2001, a 6.6 magnitude earthquake with epicenter about 20 Km W of San Vicente damaged and destroyed many towns and villages in the north area of the volcano causing some deceases. In addition, two seismic swarms were recorded beneath the northeastern flank of the volcano in April and May 2001. Searching for any link between the actual seismic activity and changes in the diffuse CO2 degassing at San Vicente, an NDIR instrument for continuos monitoring of the diffuse CO2 degassing was set up at Aguas Agrias in March 2001. Soil CO2 efflux and several meteorological and soil physical variables were measured in an hourly basis. Very significative pre-seismic and post-seismic relationships have been found in the observed diffuse CO2 efflux temporal variations related to the May 2001 seismic swarms. A sustained 50% increase on the average diffuse CO2 efflux was observed 8 days before the May 8, 5.1 magnitude earthquake. This pre-seismic behaviour may be considered a precursor of the May 2001 seismic swarm at San Vicente volcano. However, about a three-fold increase in the diffuse CO2 efflux was also observed after the intense seismicity recorded on May 8-9. These preliminary

  20. Impact of the Christchurch earthquakes on hospital staff.

    Science.gov (United States)

    Tovaranonte, Pleayo; Cawood, Tom J

    2013-06-01

    On September 4, 2010 a major earthquake caused widespread damage, but no loss of life, to Christchurch city and surrounding areas. There were numerous aftershocks, including on February 22, 2011 which, in contrast, caused substantial loss of life and major damage to the city. The research aim was to assess how these two earthquakes affected the staff in the General Medicine Department at Christchurch Hospital. Problem To date there have been no published data assessing the impact of this type of natural disaster on hospital staff in Australasia. A questionnaire that examined seven domains (demographics, personal impact, psychological impact, emotional impact, impact on care for patients, work impact, and coping strategies) was handed out to General Medicine staff and students nine days after the September 2010 earthquake and 14 days after the February 2011 earthquake. Response rates were ≥ 99%. Sixty percent of responders were earthquakes, respectively. A fifth to a third of people had to find an alternative route of transport to get to work but only eight percent to 18% took time off work. Financial impact was more severe following the February earthquake, with 46% reporting damage of >NZ $1,000, compared with 15% following the September earthquake (P earthquake than the September earthquake (42% vs 69%, P earthquake but this rose to 53% after the February earthquake (12/53 vs 45/85, P earthquake but this dropped significantly to 15% following the February earthquake (27/53 vs 13/62, P earthquakes upon General Medicine hospital staff. The effect was widespread with minor financial impact during the first but much more during the second earthquake. Moderate psychological impact was experienced in both earthquakes. This data may be useful to help prepare plans for future natural disasters. .

  1. Earthquake induced variations in extrusion rate: A numerical modeling approach to the 2006 eruption of Merapi Volcano (Indonesia)

    Science.gov (United States)

    Carr, Brett B.; Clarke, Amanda B.; de'Michieli Vitturi, Mattia

    2018-01-01

    Extrusion rates during lava dome-building eruptions are variable and eruption sequences at these volcanoes generally have multiple phases. Merapi Volcano, Java, Indonesia, exemplifies this common style of activity. Merapi is one of Indonesia's most active volcanoes and during the 20th and early 21st centuries effusive activity has been characterized by long periods of very slow (work has suggested that the peak extrusion rates observed in early June were triggered by the earthquake through either dynamic stress-induced overpressure or the addition of CO2 due to decarbonation and gas escape from new fractures in the bedrock. We use the numerical model to test the feasibility of these proposed hypotheses and show that, in order to explain the observed change in extrusion rate, an increase of approximately 5-7 MPa in magma storage zone overpressure is required. We also find that the addition of ∼1000 ppm CO2 to some portion of the magma in the storage zone following the earthquake reduces water solubility such that gas exsolution is sufficient to generate the required overpressure. Thus, the proposed mechanism of CO2 addition is a viable explanation for the peak phase of the Merapi 2006 eruption. A time-series of extrusion rate shows a sudden increase three days following the earthquake. We explain this three-day delay by the combined time required for the effects of the earthquake and corresponding CO2 increase to develop in the magma storage system (1-2 days), and the time we calculate for the affected magma to ascend from storage zone to surface (40 h). The increased extrusion rate was sustained for 2-7 days before dissipating and returning to pre-earthquake levels. During this phase, we estimate that 3.5 million m3 DRE of magma was erupted along with 11 ktons of CO2. The final phase of the 2006 eruption was characterized by highly variable extrusion rates. We demonstrate that those changes were likely controlled by failure of the edifice that had been confining

  2. Three-dimensional P-wave velocity structure derived from local earthquakes at the Katmai group of volcanoes, Alaska

    Science.gov (United States)

    Jolly, A.D.; Moran, S.C.; McNutt, S.R.; Stone, D.B.

    2007-01-01

    The three-dimensional P-wave velocity structure beneath the Katmai group of volcanoes is determined by inversion of more than 10,000 rays from over 1000 earthquakes recorded on a local 18 station short-period network between September 1996 and May 2001. The inversion is well constrained from sea level to about 6??km below sea level and encompasses all of the Katmai volcanoes; Martin, Mageik, Trident, Griggs, Novarupta, Snowy, and Katmai caldera. The inversion reduced the average RMS travel-time error from 0.22??s for locations from the standard one-dimensional model to 0.13??s for the best three-dimensional model. The final model, from the 6th inversion step, reveals a prominent low velocity zone (3.6-5.0??km/s) centered at Katmai Pass and extending from Mageik to Trident volcanoes. The anomaly has values about 20-25% slower than velocities outboard of the region (5.0-6.5??km/s). Moderately low velocities (4.5-6.0??km/s) are observed along the volcanic axis between Martin and Katmai Caldera. Griggs volcano, located about 10??km behind (northwest of) the volcanic axis, has unremarkable velocities (5.0-5.7??km/s) compared to non-volcanic regions. The highest velocities are observed between Snowy and Griggs volcanoes (5.5-6.5??km/s). Relocated hypocenters for the best 3-D model are shifted significantly relative to the standard model with clusters of seismicity at Martin volcano shifting systematically deeper by about 1??km to depths of 0 to 4??km below sea level. Hypocenters for the Katmai Caldera are more tightly clustered, relocating beneath the 1912 scarp walls. The relocated hypocenters allow us to compare spatial frequency-size distributions (b-values) using one-dimensional and three-dimensional models. We find that the distribution of b is significantly changed for Martin volcano, which was characterized by variable values (0.8 < b < 2.0) with standard locations and more uniform values (0.8 < b < 1.2) after relocation. Other seismic clusters at Mageik (1.2 < b

  3. A one-dimensional seismic model for Uturuncu volcano, Bolivia, and its impact on full moment tensor inversions

    KAUST Repository

    Shen, Weisen

    2016-11-24

    Using receiver functions, Rayleigh wave phase velocity dispersion determined from ambient noise and teleseismic earthquakes, and Rayleigh wave horizontal to vertical ground motion amplitude ratios from earthquakes observed across the PLUTONS seismic array, we construct a one-dimensional (1-D) S-wave velocity (Vs) seismic model with uncertainties for Uturuncu volcano, Bolivia, located in the central Andes and overlying the eastward-subducting Nazca plate. We find a fast upper crustal lid placed upon a low-velocity zone (LVZ) in the mid-crust. By incorporating all three types of measurements with complimentary sensitivity, we also explore the average density and Vp/Vs (ratio of P-wave to S-wave velocity) structures beneath the young silicic volcanic field. We observe slightly higher Vp/Vs and a decrease in density near the LVZ, which implies a dacitic source of the partially molten magma body. We exploit the impact of the 1-D model on full moment tensor inversion for the two largest local earthquakes recorded (both magnitude ∼3), demonstrating that the 1-D model influences the waveform fits and the estimated source type for the full moment tensor. Our 1-D model can serve as a robust starting point for future efforts to determine a three-dimensional velocity model for Uturuncu volcano.

  4. A one-dimensional seismic model for Uturuncu volcano, Bolivia, and its impact on full moment tensor inversions

    KAUST Repository

    Shen, Weisen; Alvizuri, Celso; Lin, Fan-Chi; Tape, Carl

    2016-01-01

    Using receiver functions, Rayleigh wave phase velocity dispersion determined from ambient noise and teleseismic earthquakes, and Rayleigh wave horizontal to vertical ground motion amplitude ratios from earthquakes observed across the PLUTONS seismic array, we construct a one-dimensional (1-D) S-wave velocity (Vs) seismic model with uncertainties for Uturuncu volcano, Bolivia, located in the central Andes and overlying the eastward-subducting Nazca plate. We find a fast upper crustal lid placed upon a low-velocity zone (LVZ) in the mid-crust. By incorporating all three types of measurements with complimentary sensitivity, we also explore the average density and Vp/Vs (ratio of P-wave to S-wave velocity) structures beneath the young silicic volcanic field. We observe slightly higher Vp/Vs and a decrease in density near the LVZ, which implies a dacitic source of the partially molten magma body. We exploit the impact of the 1-D model on full moment tensor inversion for the two largest local earthquakes recorded (both magnitude ∼3), demonstrating that the 1-D model influences the waveform fits and the estimated source type for the full moment tensor. Our 1-D model can serve as a robust starting point for future efforts to determine a three-dimensional velocity model for Uturuncu volcano.

  5. Spatial variations in the frequency-magnitude distribution of earthquakes at Soufriere Hills Volcano, Montserrat, West Indies

    Science.gov (United States)

    Power, J.A.; Wyss, M.; Latchman, J.L.

    1998-01-01

    The frequency-magnitude distribution of earthquakes measured by the b-value is determined as a function of space beneath Soufriere Hills Volcano, Montserrat, from data recorded between August 1, 1995 and March 31, 1996. A volume of anomalously high b-values (b > 3.0) with a 1.5 km radius is imaged at depths of 0 and 1.5 km beneath English's Crater and Chance's Peak. This high b-value anomaly extends southwest to Gage's Soufriere. At depths greater than 2.5 km volumes of comparatively low b-values (b-1) are found beneath St. George's Hill, Windy Hill, and below 2.5 km depth and to the south of English's Crater. We speculate the depth of high b-value anomalies under volcanoes may be a function of silica content, modified by some additional factors, with the most siliceous having these volumes that are highly fractured or contain high pore pressure at the shallowest depths. Copyright 1998 by the American Geophysical Union.

  6. Preliminary impact assessment of effusive eruptions at Etna volcano

    Science.gov (United States)

    Cappello, Annalisa; Michaud-Dubuy, Audrey; Branca, Stefano; De Beni, Emanuela; Del Negro, Ciro

    2016-04-01

    Lava flows are a recurring and widespread form of volcanic activity that threaten people and property around the world. The growing demographic congestion around volcanic structures increases the potential risks and costs that lava flows represent, and leads to a pressing need for faster and more accurate assessment of lava flow impact. To fully evaluate potential effects and losses that an effusive eruption may cause to society, property and environment, it is necessary to consider the hazard, the distribution of the exposed elements at stake and the associated vulnerability. Lava flow hazard assessment is at an advanced state, whereas comprehensive vulnerability assessment is lacking. Cataloguing and analyzing volcanic impacts provide insight on likely societal and physical vulnerabilities during future eruptions. Here we quantify the lava flow impact of two past main effusive eruptions of Etna volcano: the 1669, which is the biggest and destructive flank eruption to have occurred on Etna in historical time, and the 1981, lasting only 6 days, but characterized by an intense eruptive dynamics. Different elements at stake are considered, including population, hospitals, critical facilities, buildings of historic value, industrial infrastructures, gas and electricity networks, railways, roads, footways and finally land use. All these elements were combined with the 1669 and 1981 lava flow fields to quantify the social damage and economic loss.

  7. The Impact of Earthquakes on the Domestic Stock Market

    NARCIS (Netherlands)

    Scholtens, Bert; Voorhorst, Yvonne

    How do financial markets respond to the impact of earthquakes? We investigate this for more than 100 earthquakes with fatalities in 21 countries from five continents in the period 1973-2011. Using an event study methodology we conclude that there are significant negative effects on stock market

  8. The 2005 volcano-tectonic earthquake swarm in the Andaman Sea: Triggered by the 2004 great Sumatra-Andaman earthquake

    Digital Repository Service at National Institute of Oceanography (India)

    Kundu, B.; Legrand, D.; Gahalaut, K.; Gahalaut, V.K.; Mahesh, P.; KameshRaju, K.A.; Catherine, J.K.; Ambikapthy, A.; Chadha, R.K.

    Raju3, J.K. Catherine1, A. Ambikapthy1, R.K.Chadha1 1. National Geophysical Research Institute (CSIR), Hyderabad-500007, India 2. UNAM, Instituto de Geofísica, Av. Universidad 3000, Ciudad Universitaria, Del. Coyoacán, C.P. 04510. México D....F. México. 3. National Institute of Oceanography (CSIR), Dona Paula, Goa-403004, India *Corresponding Author (Email: rilbhaskar@gmail.com) Abstract: A 6-days duration earthquakes swarm occurred in the Andaman Sea, 31 days after the giant 2004...

  9. Short-term volcano-tectonic earthquake forecasts based on a moving mean recurrence time algorithm: the El Hierro seismo-volcanic crisis experience

    Science.gov (United States)

    García, Alicia; De la Cruz-Reyna, Servando; Marrero, José M.; Ortiz, Ramón

    2016-05-01

    Under certain conditions, volcano-tectonic (VT) earthquakes may pose significant hazards to people living in or near active volcanic regions, especially on volcanic islands; however, hazard arising from VT activity caused by localized volcanic sources is rarely addressed in the literature. The evolution of VT earthquakes resulting from a magmatic intrusion shows some orderly behaviour that may allow the occurrence and magnitude of major events to be forecast. Thus governmental decision makers can be supplied with warnings of the increased probability of larger-magnitude earthquakes on the short-term timescale. We present here a methodology for forecasting the occurrence of large-magnitude VT events during volcanic crises; it is based on a mean recurrence time (MRT) algorithm that translates the Gutenberg-Richter distribution parameter fluctuations into time windows of increased probability of a major VT earthquake. The MRT forecasting algorithm was developed after observing a repetitive pattern in the seismic swarm episodes occurring between July and November 2011 at El Hierro (Canary Islands). From then on, this methodology has been applied to the consecutive seismic crises registered at El Hierro, achieving a high success rate in the real-time forecasting, within 10-day time windows, of volcano-tectonic earthquakes.

  10. The Lushan earthquake and the giant panda: impacts and conservation.

    Science.gov (United States)

    Zhang, Zejun; Yuan, Shibin; Qi, Dunwu; Zhang, Mingchun

    2014-06-01

    Earthquakes not only result in a great loss of human life and property, but also have profound effects on the Earth's biodiversity. The Lushan earthquake occurred on 20 Apr 2013, with a magnitude of 7.0 and an intensity of 9.0 degrees. A distance of 17.0 km from its epicenter to the nearest distribution site of giant pandas recorded in the Third National Survey was determined. Making use of research on the Wenchuan earthquake (with a magnitude of 8.0), which occurred approximately 5 years ago, we briefly analyze the impacts of the Lushan earthquake on giant pandas and their habitat. An earthquake may interrupt ongoing behaviors of giant pandas and may also cause injury or death. In addition, an earthquake can damage conservation facilities for pandas, and result in further habitat fragmentation and degradation. However, from a historical point of view, the impacts of human activities on giant pandas and their habitat may, in fact, far outweigh those of natural disasters such as earthquakes. Measures taken to promote habitat restoration and conservation network reconstruction in earthquake-affected areas should be based on requirements of giant pandas, not those of humans. © 2013 International Society of Zoological Sciences, Institute of Zoology/Chinese Academy of Sciences and Wiley Publishing Asia Pty Ltd.

  11. Laboratory simulations of fluid/gas induced micro-earthquakes: application to volcano seismology.

    Directory of Open Access Journals (Sweden)

    Philip Michael Benson

    2014-11-01

    Full Text Available Understanding different seismic signals recorded in active volcanic regions allows geoscientists to derive insight into the processes that generate them. A key type is known as Low Frequency or Long Period (LP event, generally understood to be generated by different fluid types resonating in cracks and faults. The physical mechanisms of these signals have been linked to either resonance/turbulence within fluids, or as a result of fluids ‘sloshing’ due to a mixture of gas and fluid being present in the system. Less well understood, however, is the effect of the fluid type (phase on the measured signal. To explore this, we designed an experiment in which we generated a precisely controlled liquid to gas transition in a closed system by inducing rapid decompression of fluid-filled fault zones in a sample of basalt from Mt. Etna Volcano, Italy. We find that fluid phase transition is accompanied by a marked frequency shift in the accompanying microseismic dataset that can be compared to volcano seismic data. Moreover, our induced seismic activity occurs at pressure conditions equivalent to hydrostatic depths of 200 to 750 meters. This is consistent with recently measured dominant frequencies of LP events and with numerous models.

  12. Earthquakes

    Science.gov (United States)

    An earthquake happens when two blocks of the earth suddenly slip past one another. Earthquakes strike suddenly, violently, and without warning at any time of the day or night. If an earthquake occurs in a populated area, it may cause ...

  13. The key role of eyewitnesses in rapid earthquake impact assessment

    Science.gov (United States)

    Bossu, Rémy; Steed, Robert; Mazet-Roux, Gilles; Roussel, Frédéric; Etivant, Caroline

    2014-05-01

    Uncertainties in rapid earthquake impact models are intrinsically large even when excluding potential indirect losses (fires, landslides, tsunami…). The reason is that they are based on several factors which are themselves difficult to constrain, such as the geographical distribution of shaking intensity, building type inventory and vulnerability functions. The difficulties can be illustrated by two boundary cases. For moderate (around M6) earthquakes, the size of potential damage zone and the epicentral location uncertainty share comparable dimension of about 10-15km. When such an earthquake strikes close to an urban area, like in 1999, in Athens (M5.9), earthquake location uncertainties alone can lead to dramatically different impact scenario. Furthermore, for moderate magnitude, the overall impact is often controlled by individual accidents, like in 2002 in Molise, Italy (M5.7), in Bingol, Turkey (M6.4) in 2003 or in Christchurch, New Zealand (M6.3) where respectively 23 out of 30, 84 out of 176 and 115 out of 185 of the causalities perished in a single building failure. Contrastingly, for major earthquakes (M>7), the point source approximation is not valid anymore, and impact assessment requires knowing exactly where the seismic rupture took place, whether it was unilateral, bilateral etc.… and this information is not readily available directly after the earthquake's occurrence. In-situ observations of actual impact provided by eyewitnesses can dramatically reduce impact models uncertainties. We will present the overall strategy developed at the EMSC which comprises of crowdsourcing and flashsourcing techniques, the development of citizen operated seismic networks, and the use of social networks to engage with eyewitnesses within minutes of an earthquake occurrence. For instance, testimonies are collected through online questionnaires available in 32 languages and automatically processed in maps of effects. Geo-located pictures are collected and then

  14. Psychological impact of the Canterbury earthquakes on university staff.

    Science.gov (United States)

    Bell, Caroline; Carter, Frances; Boden, Joseph; Wilkinson, Tim; McKenzie, Jan; Ali, Anthony

    2016-02-19

    To assess the impact of the Canterbury earthquakes on the psychological functioning of university staff, to identify predictors of adverse psychological functioning and to survey how different aspects of work roles (academic, teaching, clinical, administrative) were affected. Eighteen months following the most severe earthquake, 119 staff from the University of Otago based in Christchurch completed a retrospective survey. This included demographic information, a measure of earthquake exposure, standardised and self-rated measures to identify psychological distress and measures of how people perceived different aspects of their work roles were impacted. A substantial minority of staff reported moderate-extreme difficulties on the Depression, Anxiety and Stress Scale (DASS) subscales 18 months following the most severe earthquake (Depression=9%; Anxiety=3%; Stress =13%). Predictors of distress were higher levels of exposure to earthquake-related stressors, neuroticism and prior mental health disorders. There was an association between impact and work roles that was hierarchical; academic and administrative roles were most affected, followed by teaching with the least impact on clinical roles. This study shows that psychological symptoms following a disaster are common, but in a retrospective survey most people report that these improve with time. A minority however, continue to report difficulties which persist even 18 months post disaster. It also gives insights into how different work roles were impacted and from this makes suggestions for how organisations can support staff over difficult times.

  15. Long Period (LP) volcanic earthquake source location at Merapi volcano by using dense array technics

    Science.gov (United States)

    Metaxian, Jean Philippe; Budi Santoso, Agus; Laurin, Antoine; Subandriyo, Subandriyo; Widyoyudo, Wiku; Arshab, Ghofar

    2015-04-01

    Since 2010, Merapi shows unusual activity compared to last decades. Powerful phreatic explosions are observed; some of them are preceded by LP signals. In the literature, LP seismicity is thought to be originated within the fluid, and therefore to be representative of the pressurization state of the volcano plumbing system. Another model suggests that LP events are caused by slow, quasi-brittle, low stress-drop failure driven by transient upper-edifice deformations. Knowledge of the spatial distribution of LP events is fundamental for better understanding the physical processes occurring in the conduit, as well as for the monitoring and the improvement of eruption forecasting. LP events recorded at Merapi have a spectral content dominated by frequencies between 0.8 and 3 Hz. To locate the source of these events, we installed a seismic antenna composed of 4 broadband CMG-6TD Güralp stations. This network has an aperture of 300 m. It is located on the site of Pasarbubar, between 500 and 800 m from the crater rim. Two multi-parameter stations (seismic, tiltmeter, S-P) located in the same area, equipped with broadband CMG-40T Güralp sensors may also be used to complete the data of the antenna. The source of LP events is located by using different approaches. In the first one, we used a method based on the measurement of the time delays between the early beginnings of LP events for each array receiver. The observed differences of time delays obtained for each pair of receivers are compared to theoretical values calculated from the travel times computed between grid nodes, which are positioned in the structure, and each receiver. In a second approach, we estimate the slowness vector by using MUSIC algorithm applied to 3-components data. From the slowness vector, we deduce the back-azimuth and the incident angle, which give an estimation of LP source depth in the conduit. This work is part of the Domerapi project funded by French Agence Nationale de la Recherche (https

  16. Long-term impact of earthquakes on sleep quality.

    Science.gov (United States)

    Tempesta, Daniela; Curcio, Giuseppe; De Gennaro, Luigi; Ferrara, Michele

    2013-01-01

    We investigated the impact of the 6.3 magnitude 2009 L'Aquila (Italy) earthquake on standardized self-report measures of sleep quality (Pittsburgh Sleep Quality Index, PSQI) and frequency of disruptive nocturnal behaviours (Pittsburgh Sleep Quality Index-Addendum, PSQI-A) two years after the natural disaster. Self-reported sleep quality was assessed in 665 L'Aquila citizens exposed to the earthquake compared with a different sample (n = 754) of L'Aquila citizens tested 24 months before the earthquake. In addition, sleep quality and disruptive nocturnal behaviours (DNB) of people exposed to the traumatic experience were compared with people that in the same period lived in different areas ranging between 40 and 115 km from the earthquake epicenter (n = 3574). The comparison between L'Aquila citizens before and after the earthquake showed a significant deterioration of sleep quality after the exposure to the trauma. In addition, two years after the earthquake L'Aquila citizens showed the highest PSQI scores and the highest incidence of DNB compared to subjects living in the surroundings. Interestingly, above-the-threshold PSQI scores were found in the participants living within 70 km from the epicenter, while trauma-related DNBs were found in people living in a range of 40 km. Multiple regressions confirmed that proximity to the epicenter is predictive of sleep disturbances and DNB, also suggesting a possible mediating effect of depression on PSQI scores. The psychological effects of an earthquake may be much more pervasive and long-lasting of its building destruction, lasting for years and involving a much larger population. A reduced sleep quality and an increased frequency of DNB after two years may be a risk factor for the development of depression and posttraumatic stress disorder.

  17. Volcanic gas impacts on vegetation at Turrialba Volcano, Costa Rica

    Science.gov (United States)

    Teasdale, R.; Jenkins, M.; Pushnik, J.; Houpis, J. L.; Brown, D. L.

    2010-12-01

    Turrialba volcano is an active composite stratovolcano that is located approximately 40 km east of San Jose, Costa Rica. Seismic activity and degassing have increased since 2005, and gas compositions reflect further increased activity since 2007 peaking in January 2010 with a phreatic eruption. Gas fumes dispersed by trade winds toward the west, northwest, and southwest flanks of Turrialba volcano have caused significant vegetation kill zones, in areas important to local agriculture, including dairy pastures and potato fields, wildlife and human populations. In addition to extensive vegetative degradation is the potential for soil and water contamination and soil erosion. Summit fumarole temperatures have been measured over 200 degrees C and gas emissions are dominated by SO2; gas and vapor plumes reach up to 2 km (fumaroles and gases are measured regularly by OVSICORI-UNA). A recent network of passive air sampling, monitoring of water temperatures of hydrothermal systems, and soil pH measurements coupled with measurement of the physiological status of surrounding plants using gas exchange and fluorescence measurements to: (1) identify physiological correlations between leaf-level gas exchange and chlorophyll fluorescence measurements of plants under long term stress induced by the volcanic gas emissions, and (2) use measurements in tandem with remotely sensed reflectance-derived fluorescence ratio indices to track natural photo inhibition caused by volcanic gas emissions, for use in monitoring plant stress and photosynthetic function. Results may prove helpful in developing potential land management strategies to maintain the biological health of the area.

  18. Potential ash impact from Antarctic volcanoes: Insights from Deception Island's most recent eruption.

    Science.gov (United States)

    Geyer, A; Marti, A; Giralt, S; Folch, A

    2017-11-28

    Ash emitted during explosive volcanic eruptions may disperse over vast areas of the globe posing a threat to human health and infrastructures and causing significant disruption to air traffic. In Antarctica, at least five volcanoes have reported historic activity. However, no attention has been paid to the potential socio-economic and environmental consequences of an ash-forming eruption occurring at high southern latitudes. This work shows how ash from Antarctic volcanoes may pose a higher threat than previously believed. As a case study, we evaluate the potential impacts of ash for a given eruption scenario from Deception Island, one of the most active volcanoes in Antarctica. Numerical simulations using the novel MMB-MONARCH-ASH model demonstrate that volcanic ash emitted from Antarctic volcanoes could potentially encircle the globe, leading to significant consequences for global aviation safety. Results obtained recall the need for performing proper hazard assessment on Antarctic volcanoes, and are crucial for understanding the patterns of ash distribution at high southern latitudes with strong implications for tephrostratigraphy, which is pivotal to synchronize palaeoclimatic records.

  19. The Quanzhou large earthquake: environment impact and deep process

    Science.gov (United States)

    WANG, Y.; Gao*, R.; Ye, Z.; Wang, C.

    2017-12-01

    The Quanzhou earthquake is the largest earthquake in China's southeast coast in history. The ancient city of Quanzhou and its adjacent areas suffered serious damage. Analysis of the impact of Quanzhou earthquake on human activities, ecological environment and social development will provide an example for the research on environment and human interaction.According to historical records, on the night of December 29, 1604, a Ms 8.0 earthquake occurred in the sea area at the east of Quanzhou (25.0°N, 119.5°E) with a focal depth of 25 kilometers. It affected to a maximum distance of 220 kilometers from the epicenter and caused serious damage. Quanzhou, which has been known as one of the world's largest trade ports during Song and Yuan periods was heavily destroyed by this earthquake. The destruction of the ancient city was very serious and widespread. The city wall collapsed in Putian, Nanan, Tongan and other places. The East and West Towers of Kaiyuan Temple, which are famous with magnificent architecture in history, were seriously destroyed.Therefore, an enormous earthquake can exert devastating effects on human activities and social development in the history. It is estimated that a more than Ms. 5.0 earthquake in the economically developed coastal areas in China can directly cause economic losses for more than one hundred million yuan. This devastating large earthquake that severely destroyed the Quanzhou city was triggered under a tectonic-extensional circumstance. In this coastal area of the Fujian Province, the crust gradually thins eastward from inland to coast (less than 29 km thick crust beneath the coast), the lithosphere is also rather thin (60 70 km), and the Poisson's ratio of the crust here appears relatively high. The historical Quanzhou Earthquake was probably correlated with the NE-striking Littoral Fault Zone, which is characterized by right-lateral slip and exhibiting the most active seismicity in the coastal area of Fujian. Meanwhile, tectonic

  20. Calibration and validation of earthquake catastrophe models. Case study: Impact Forecasting Earthquake Model for Algeria

    Science.gov (United States)

    Trendafiloski, G.; Gaspa Rebull, O.; Ewing, C.; Podlaha, A.; Magee, B.

    2012-04-01

    Calibration and validation are crucial steps in the production of the catastrophe models for the insurance industry in order to assure the model's reliability and to quantify its uncertainty. Calibration is needed in all components of model development including hazard and vulnerability. Validation is required to ensure that the losses calculated by the model match those observed in past events and which could happen in future. Impact Forecasting, the catastrophe modelling development centre of excellence within Aon Benfield, has recently launched its earthquake model for Algeria as a part of the earthquake model for the Maghreb region. The earthquake model went through a detailed calibration process including: (1) the seismic intensity attenuation model by use of macroseismic observations and maps from past earthquakes in Algeria; (2) calculation of the country-specific vulnerability modifiers by use of past damage observations in the country. The use of Benouar, 1994 ground motion prediction relationship was proven as the most appropriate for our model. Calculation of the regional vulnerability modifiers for the country led to 10% to 40% larger vulnerability indexes for different building types compared to average European indexes. The country specific damage models also included aggregate damage models for residential, commercial and industrial properties considering the description of the buildings stock given by World Housing Encyclopaedia and the local rebuilding cost factors equal to 10% for damage grade 1, 20% for damage grade 2, 35% for damage grade 3, 75% for damage grade 4 and 100% for damage grade 5. The damage grades comply with the European Macroseismic Scale (EMS-1998). The model was validated by use of "as-if" historical scenario simulations of three past earthquake events in Algeria M6.8 2003 Boumerdes, M7.3 1980 El-Asnam and M7.3 1856 Djidjelli earthquake. The calculated return periods of the losses for client market portfolio align with the

  1. Asia-Pacific Region Global Earthquake and Volcanic Eruption Risk Management (G-EVER) project and a next-generation real-time volcano hazard assessment system

    Science.gov (United States)

    Takarada, S.

    2012-12-01

    The first Workshop of Asia-Pacific Region Global Earthquake and Volcanic Eruption Risk Management (G-EVER1) was held in Tsukuba, Ibaraki Prefecture, Japan from February 23 to 24, 2012. The workshop focused on the formulation of strategies to reduce the risks of disasters worldwide caused by the occurrence of earthquakes, tsunamis, and volcanic eruptions. More than 150 participants attended the workshop. During the workshop, the G-EVER1 accord was approved by the participants. The Accord consists of 10 recommendations like enhancing collaboration, sharing of resources, and making information about the risks of earthquakes and volcanic eruptions freely available and understandable. The G-EVER Hub website (http://g-ever.org) was established to promote the exchange of information and knowledge among the Asia-Pacific countries. Several G-EVER Working Groups and Task Forces were proposed. One of the working groups was tasked to make the next-generation real-time volcano hazard assessment system. The next-generation volcano hazard assessment system is useful for volcanic eruption prediction, risk assessment, and evacuation at various eruption stages. The assessment system is planned to be developed based on volcanic eruption scenario datasets, volcanic eruption database, and numerical simulations. Defining volcanic eruption scenarios based on precursor phenomena leading up to major eruptions of active volcanoes is quite important for the future prediction of volcanic eruptions. Compiling volcanic eruption scenarios after a major eruption is also important. A high quality volcanic eruption database, which contains compilations of eruption dates, volumes, and styles, is important for the next-generation volcano hazard assessment system. The volcanic eruption database is developed based on past eruption results, which only represent a subset of possible future scenarios. Hence, different distributions from the previous deposits are mainly observed due to the differences in

  2. Hazard map for volcanic ballistic impacts at El Chichón volcano (Mexico)

    Science.gov (United States)

    Alatorre-Ibarguengoitia, Miguel; Ramos-Hernández, Silvia; Jiménez-Aguilar, Julio

    2014-05-01

    The 1982 eruption of El Chichón Volcano in southeastern Mexico had a strong social and environmental impact. The eruption resulted in the worst volcanic disaster in the recorded history of Mexico, causing about 2,000 casualties, displacing thousands, and producing severe economic losses. Even when some villages were relocated after the 1982 eruption, many people still live and work in the vicinities of the volcano and may be affected in the case of a new eruption. The hazard map of El Chichón volcano (Macías et al., 2008) comprises pyroclastic flows, pyroclastic surges, lahars and ash fall but not ballistic projectiles, which represent an important threat to people, infrastructure and vegetation in the case of an eruption. In fact, the fatalities reported in the first stage of the 1982 eruption were caused by roof collapse induced by ashfall and lithic ballistic projectiles. In this study, a general methodology to delimit the hazard zones for volcanic ballistic projectiles during volcanic eruptions is applied to El Chichón volcano. Different scenarios are defined based on the past activity of the volcano and parameterized by considering the maximum kinetic energy associated with ballistic projectiles ejected during previous eruptions. A ballistic model is used to reconstruct the "launching" kinetic energy of the projectiles observed in the field. The maximum ranges expected for the ballistics in the different explosive scenarios defined for El Chichón volcano are presented in a ballistic hazard map which complements the published hazard map. These maps assist the responsible authorities to plan the definition and mitigation of restricted areas during volcanic crises.

  3. Catalog of earthquake hypocenters at Redoubt Volcano and Mt. Spurr, Alaska: October 12, 1989 - December 31, 1990

    Science.gov (United States)

    Power, John A.; March, Gail D.; Lahr, John C.; Jolly, Arthur D.; Cruse, Gina R.

    1993-01-01

    The Alaska Volcano Observatory (AVO), a cooperative program of the U.S. Geological Survey, the Geophysical Institute of the University of Alaska, Fairbanks, and the Alaska Division of Geological and Geophysical Surveys, began a program of seismic monitoring at potentially active volcanoes in the Cook Inlet region in 1988. Seismic monitoring of this area was previously accomplished by two independent seismic networks operated by the U.S. Geological Survey (Northern Cook Inlet) and the Geophysical Institute (Southern Cook Inlet). In 1989 the AVO seismic program consisted of three small-aperture networks of six, five, and six stations on Mt. Spurr, Redoubt Volcano, and Augustine Volcano respectively. Thirty-five other stations were operated in the Cook Inlet region as part of the AVO program. During 1990 six additional stations were added to the Redoubt network in response to eruptive activity, and three stations were installed at Iliamna Volcano. The principal objectives of the AVO program have been the seismic surveillance of the Cook Inlet volcanoes and the investigation of seismic processes associated with active volcanism.

  4. Prompt Assessment of Global Earthquakes for Response (PAGER): A System for Rapidly Determining the Impact of Earthquakes Worldwide

    Science.gov (United States)

    Earle, Paul S.; Wald, David J.; Jaiswal, Kishor S.; Allen, Trevor I.; Hearne, Michael G.; Marano, Kristin D.; Hotovec, Alicia J.; Fee, Jeremy

    2009-01-01

    Within minutes of a significant earthquake anywhere on the globe, the U.S. Geological Survey (USGS) Prompt Assessment of Global Earthquakes for Response (PAGER) system assesses its potential societal impact. PAGER automatically estimates the number of people exposed to severe ground shaking and the shaking intensity at affected cities. Accompanying maps of the epicentral region show the population distribution and estimated ground-shaking intensity. A regionally specific comment describes the inferred vulnerability of the regional building inventory and, when available, lists recent nearby earthquakes and their effects. PAGER's results are posted on the USGS Earthquake Program Web site (http://earthquake.usgs.gov/), consolidated in a concise one-page report, and sent in near real-time to emergency responders, government agencies, and the media. Both rapid and accurate results are obtained through manual and automatic updates of PAGER's content in the hours following significant earthquakes. These updates incorporate the most recent estimates of earthquake location, magnitude, faulting geometry, and first-hand accounts of shaking. PAGER relies on a rich set of earthquake analysis and assessment tools operated by the USGS and contributing Advanced National Seismic System (ANSS) regional networks. A focused research effort is underway to extend PAGER's near real-time capabilities beyond population exposure to quantitative estimates of fatalities, injuries, and displaced population.

  5. The economic costs of natural disasters globally from 1900-2015: historical and normalised floods, storms, earthquakes, volcanoes, bushfires, drought and other disasters

    Science.gov (United States)

    Daniell, James; Wenzel, Friedemann; Schaefer, Andreas

    2016-04-01

    For the first time, a breakdown of natural disaster losses from 1900-2015 based on over 30,000 event economic losses globally is given based on increased analysis within the CATDAT Damaging Natural Disaster databases. Using country-CPI and GDP deflator adjustments, over 7 trillion (2015-adjusted) in losses have occurred; over 40% due to flood/rainfall, 26% due to earthquake, 19% due to storm effects, 12% due to drought, 2% due to wildfire and under 1% due to volcano. Using construction cost indices, higher percentages of flood losses are seen. Depending on how the adjustment of dollars are made to 2015 terms (CPI vs. construction cost indices), between 6.5 and 14.0 trillion USD (2015-adjusted) of natural disaster losses have been seen from 1900-2015 globally. Significant reductions in economic losses have been seen in China and Japan from 1950 onwards. An AAL of around 200 billion in the last 16 years has been seen equating to around 0.25% of Global GDP or around 0.1% of Net Capital Stock per year. Normalised losses have also been calculated to examine the trends in vulnerability through time for economic losses. The normalisation methodology globally using the exposure databases within CATDAT that were undertaken previously in papers for the earthquake and volcano databases, are used for this study. The original event year losses are adjusted directly by capital stock change, very high losses are observed with respect to floods over time (however with improved flood control structures). This shows clear trends in the improvement of building stock towards natural disasters and a decreasing trend in most perils for most countries.

  6. Impact of earthquake-induced tsunamis on public health

    Science.gov (United States)

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

    2017-04-01

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

  7. The impact of soil suction variation on earthquake intensity indices

    Directory of Open Access Journals (Sweden)

    Biglari Mahnoosh

    2016-01-01

    Full Text Available Soil properties can completely change the ground motion characteristics as they travel from the bedrock to the surface because, soil as a low-pass filter, may amplify or deamplify seismic motions in some frequencies on the wave travelling path. Recent studies about the advanced unsaturated soil mechanics clearly shows that dynamic properties of soils, including small-strain shear modulus (Gmax, shear modulus reduction (G/Gmax, and damping ratio (D curves are affected by changes in the soil suction level. The current study present nonlinear time-dependent analysis of three different unsaturated soils available in the literature with different ranges of nonlinear behaviour that earlier have been studied on unsaturated dynamic models. Since, the earthquake intensity parameters can be used to describe the damage potential of an earthquake, the focus of this paper is to evaluate the impact of the suction variation on the engineering ground motion parameters, including peak values of strong motion, Vmax/Amax, root-mean-square acceleration, Arias intensity, characteristic intensity, cumulative absolute velocity, acceleration spectrum intensity, effective design acceleration, A95 parameter and predominant period separately under the near-field and the far-field seismicity categories.

  8. Charles Darwin's earthquake reports

    Science.gov (United States)

    Galiev, Shamil

    2010-05-01

    problems which began to discuss only during the last time. Earthquakes often precede volcanic eruptions. According to Darwin, the earthquake-induced shock may be a common mechanism of the simultaneous eruptions of the volcanoes separated by long distances. In particular, Darwin wrote that ‘… the elevation of many hundred square miles of territory near Concepcion is part of the same phenomenon, with that splashing up, if I may so call it, of volcanic matter through the orifices in the Cordillera at the moment of the shock;…'. According to Darwin the crust is a system where fractured zones, and zones of seismic and volcanic activities interact. Darwin formulated the task of considering together the processes studied now as seismology and volcanology. However the difficulties are such that the study of interactions between earthquakes and volcanoes began only recently and his works on this had relatively little impact on the development of geosciences. In this report, we discuss how the latest data on seismic and volcanic events support the Darwin's observations and ideas about the 1835 Chilean earthquake. The material from researchspace. auckland. ac. nz/handle/2292/4474 is used. We show how modern mechanical tests from impact engineering and simple experiments with weakly-cohesive materials also support his observations and ideas. On the other hand, we developed the mathematical theory of the earthquake-induced catastrophic wave phenomena. This theory allow to explain the most important aspects the Darwin's earthquake reports. This is achieved through the simplification of fundamental governing equations of considering problems to strongly-nonlinear wave equations. Solutions of these equations are constructed with the help of analytic and numerical techniques. The solutions can model different strongly-nonlinear wave phenomena which generate in a variety of physical context. A comparison with relevant experimental observations is also presented.

  9. The human impact of volcanoes: a historical review of events 1900-2009 and systematic literature review.

    Science.gov (United States)

    Doocy, Shannon; Daniels, Amy; Dooling, Shayna; Gorokhovich, Yuri

    2013-04-16

    Introduction. More than 500 million people live within the potential exposure range of a volcano. The risk of catastrophic losses in future eruptions is significant given population growth, proximities of major cities to volcanoes, and the possibility of larger eruptions. The objectives of this review are to describe the impact of volcanoes on the human population, in terms of mortality, injury, and displacement and, to the extent possible, identify risk factors associated with these outcomes. This is one of five reviews on the human impact of natural disasters. Methods. Data on the impact of volcanoes were compiled using two methods, a historical review of volcano events from 1900 to 2009 from multiple databases and a systematic literature review of publications ending in October 2012. Analysis included descriptive statistics and bivariate tests for associations between volcano mortality and characteristics using STATA 11. Findings. There were a total of 91,789 deaths (range: 81,703-102,372), 14,068 injuries (range 11,541-17,922), and 4.72 million people affected by volcanic events between 1900 and 2008. Inconsistent reporting suggests this is an underestimate, particularly in terms of numbers injured and affected. The primary causes of mortality in recent volcanic eruptions were ash asphyxiation, thermal injuries from pyroclastic flow, and trauma. Mortality was concentrated with the ten deadliest eruptions accounting for more than 80% of deaths; 84% of fatalities occurred in four locations (the Island of Martinique (France), Colombia, Indonesia, and Guatemala). Conclusions. Changes in land use practices and population growth provide a background for increasing risk; in conjunction with increasing urbanization in at risk areas, this poses a challenge for future volcano preparedness and mitigation efforts.

  10. Impact-based earthquake alerts with the U.S. Geological Survey's PAGER system: what's next?

    Science.gov (United States)

    Wald, D.J.; Jaiswal, K.S.; Marano, K.D.; Garcia, D.; So, E.; Hearne, M.

    2012-01-01

    In September 2010, the USGS began publicly releasing earthquake alerts for significant earthquakes around the globe based on estimates of potential casualties and economic losses with its Prompt Assessment of Global Earthquakes for Response (PAGER) system. These estimates significantly enhanced the utility of the USGS PAGER system which had been, since 2006, providing estimated population exposures to specific shaking intensities. Quantifying earthquake impacts and communicating estimated losses (and their uncertainties) to the public, the media, humanitarian, and response communities required a new protocol—necessitating the development of an Earthquake Impact Scale—described herein and now deployed with the PAGER system. After two years of PAGER-based impact alerting, we now review operations, hazard calculations, loss models, alerting protocols, and our success rate for recent (2010-2011) events. This review prompts analyses of the strengths, limitations, opportunities, and pressures, allowing clearer definition of future research and development priorities for the PAGER system.

  11. Translating Volcano Hazards Research in the Cascades Into Community Preparedness

    Science.gov (United States)

    Ewert, J. W.; Driedger, C. L.

    2015-12-01

    Research by the science community into volcanic histories and physical processes at Cascade volcanoes in the states of Washington, Oregon, and California has been ongoing for over a century. Eruptions in the 20th century at Lassen Peak and Mount St. Helen demonstrated the active nature of Cascade volcanoes; the 1980 eruption of Mount St. Helens was a defining moment in modern volcanology. The first modern volcano hazards assessments were produced by the USGS for some Cascade volcanoes in the 1960s. A rich scientific literature exists, much of which addresses hazards at these active volcanoes. That said community awareness, planning, and preparation for eruptions generally do not occur as a result of a hazard analyses published in scientific papers, but by direct communication with scientists. Relative to other natural hazards, volcanic eruptions (or large earthquakes, or tsunami) are outside common experience, and the public and many public officials are often surprised to learn of the impacts volcanic eruptions could have on their communities. In the 1980s, the USGS recognized that effective hazard communication and preparedness is a multi-faceted, long-term undertaking and began working with federal, state, and local stakeholders to build awareness and foster community action about volcano hazards. Activities included forming volcano-specific workgroups to develop coordination plans for volcano emergencies; a concerted public outreach campaign; curriculum development and teacher training; technical training for emergency managers and first responders; and development of hazard information that is accessible to non-specialists. Outcomes include broader ownership of volcano hazards as evidenced by bi-national exchanges of emergency managers, community planners, and first responders; development by stakeholders of websites focused on volcano hazards mitigation; and execution of table-top and functional exercises, including evacuation drills by local communities.

  12. Impacts of the 2010 Haitian earthquake in the diaspora: findings from Little Haiti, Miami, FL.

    Science.gov (United States)

    Kobetz, Erin; Menard, Janelle; Kish, Jonathan; Bishop, Ian; Hazan, Gabrielle; Nicolas, Guerda

    2013-04-01

    In January 2010, a massive earthquake struck Haiti resulting in unprecedented damage. Little attention, however, has focused on the earthquake's mental health impact in the Haitian diaspora community. As part of an established community-based participatory research initiative in Little Haiti, the predominately Haitian neighborhood in Miami, FL, USA, community health workers conducted surveys with neighborhood residents about earthquake-related losses, coping strategies, and depressive/traumatic symptomology. Findings reveal the earthquake strongly impacted the diaspora community and highlights prominent coping strategies. Following the earthquake, only a small percentage of participants self-reported engaging in any negative health behaviors. Instead, a majority relied on their social networks for support. This study contributes to the discourse on designing culturally-responsive mental health initiatives for the Haitian diaspora and the ability of existing community-academic partnerships to rapidly adapt to community needs.

  13. Determination and uncertainty of moment tensors for microearthquakes at Okmok Volcano, Alaska

    Czech Academy of Sciences Publication Activity Database

    Pesicek, J. D.; Šílený, Jan; Prejean, S. G.; Thurber, C. H.

    2012-01-01

    Roč. 190, č. 3 (2012), s. 1689-1709 ISSN 0956-540X R&D Projects: GA ČR GAP210/12/2235 Institutional research plan: CEZ:AV0Z30120515 Keywords : earthquake source observations * volcano seismology * body waves Subject RIV: DC - Siesmology, Volcanology, Earth Structure Impact factor: 2.853, year: 2012

  14. New Perspectives on the Climatic Impact of the 1600 Eruption of Huaynaputina Volcano, Peru

    Science.gov (United States)

    Verosub, K. L.; Lippman, J.

    2007-05-01

    A critical test of the new understanding of volcanic aerosols developed since 1982 is to determine if it can predict the effects of larger eruptions than those that have occurred since El Chichon. To do that, requires detailed information about the effects of specific large eruptions. We have been investigating the human and climatic impacts of the 1600 eruption of Huaynaputina volcano in Peru. The estimated Volcanic Explosivity Index for this eruption is 6, which is comparable to that of the 1815 eruption of Tambora volcano in Indonesia, which produced global cooling and led to crop failures, famine and social unrest. On the basis of tree-ring data, Briffa et al. (1998) suggested that the most severe short-term Northern Hemisphere cooling event of the past 600 years occurred in 1601, the year following the Huaynaputina eruption. In order gain a better understanding of the nature and extent of this cooling, we have been collecting annual time series that provide information about climatic conditions during time intervals that bracket the Huaynaputina eruption. Among the time series that we have examined (or plan to examine) are ice conditions in the harbors of Tallinn, Estonia, and Riga, Latvia and in Lake Suwa in Japan: cherry blossom blooming (sakura) dates from Kyoto, Japan; records of agricultural production from China and Russia; tithe records from the Spanish colonial empire; dates of the beginning of the wine harvest in France and the rye harvest in Sweden; prices of agricultural commodities in Europe; and river flows from the Nile and the Colorado. Often, in the records we have examined, 1601 shows up as one of the coldest years, if not the coldest year. In addition, the worst famines in Russian history took place between 1601 and 1603, which eventually led to the overthrow of Tsar Boris Gudonov. Thus, there is considerable evidence that the climatic impacts of the Huaynaputina eruption were comparable to those from the Tambora eruption. This result is

  15. Earthquake effect on volcano and the geological structure in central java using tomography travel time method and relocation hypocenter by grid search method

    International Nuclear Information System (INIS)

    Suharsono; Nurdian, S. W; Palupi, I. R.

    2016-01-01

    Relocating hypocenter is a way to improve the velocity model of the subsurface. One of the method is Grid Search. To perform the distribution of the velocity in subsurface by tomography method, it is used the result of relocating hypocenter to be a reference for subsurface analysis in volcanic and major structural patterns, such as in Central Java. The main data of this study is the earthquake data recorded from 1952 to 2012 with the P wave number is 9162, the number of events is 2426 were recorded by 30 stations located in the vicinity of Central Java. Grid search method has some advantages they are: it can relocate the hypocenter more accurate because this method is dividing space lattice model into blocks, and each grid block can only be occupied by one point hypocenter. Tomography technique is done by travel time data that has had relocated with inversion pseudo bending method. Grid search relocated method show that the hypocenter's depth is shallower than before and the direction is to the south, the hypocenter distribution is modeled into the subduction zone between the continent of Eurasia with the Indo-Australian with an average angle of 14 °. The tomography results show the low velocity value is contained under volcanoes with value of -8% to -10%, then the pattern of the main fault structure in Central Java can be description by the results of tomography at high velocity that is from 8% to 10% with the direction is northwest and northeast-southwest. (paper)

  16. The Advanced Rapid Imaging and Analysis (ARIA) Project: Status of SAR products for Earthquakes, Floods, Volcanoes and Groundwater-related Subsidence

    Science.gov (United States)

    Owen, S. E.; Yun, S. H.; Hua, H.; Agram, P. S.; Liu, Z.; Sacco, G. F.; Manipon, G.; Linick, J. P.; Fielding, E. J.; Lundgren, P.; Farr, T. G.; Webb, F.; Rosen, P. A.; Simons, M.

    2017-12-01

    The Advanced Rapid Imaging and Analysis (ARIA) project for Natural Hazards is focused on rapidly generating high-level geodetic imaging products and placing them in the hands of the solid earth science and local, national, and international natural hazard communities by providing science product generation, exploration, and delivery capabilities at an operational level. Space-based geodetic measurement techniques including Interferometric Synthetic Aperture Radar (InSAR), differential Global Positioning System, and SAR-based change detection have become critical additions to our toolset for understanding and mapping the damage and deformation caused by earthquakes, volcanic eruptions, floods, landslides, and groundwater extraction. Up until recently, processing of these data sets has been handcrafted for each study or event and has not generated products rapidly and reliably enough for response to natural disasters or for timely analysis of large data sets. The ARIA project, a joint venture co-sponsored by the California Institute of Technology and by NASA through the Jet Propulsion Laboratory, has been capturing the knowledge applied to these responses and building it into an automated infrastructure to generate imaging products in near real-time that can improve situational awareness for disaster response. In addition to supporting the growing science and hazard response communities, the ARIA project has developed the capabilities to provide automated imaging and analysis capabilities necessary to keep up with the influx of raw SAR data from geodetic imaging missions such as ESA's Sentinel-1A/B, now operating with repeat intervals as short as 6 days, and the upcoming NASA NISAR mission. We will present the progress and results we have made on automating the analysis of Sentinel-1A/B SAR data for hazard monitoring and response, with emphasis on recent developments and end user engagement in flood extent mapping and deformation time series for both volcano

  17. Impact of the Northridge earthquake on the mental health of veterans: results from a panel study.

    Science.gov (United States)

    Dobalian, Aram; Stein, Judith A; Heslin, Kevin C; Riopelle, Deborah; Venkatesh, Brinda; Lanto, Andrew B; Simon, Barbara; Yano, Elizabeth M; Rubenstein, Lisa V

    2011-09-01

    The 1994 earthquake that struck Northridge, California, led to the closure of the Veterans Health Administration Medical Center at Sepulveda. This article examines the earthquake's impact on the mental health of an existing cohort of veterans who had previously used the Sepulveda Veterans Health Administration Medical Center. From 1 to 3 months after the disaster, trained interviewers made repeated attempts to contact participants by telephone to administer a repeated measures follow-up design survey based on a survey that had been done preearthquake. Postearthquake data were obtained on 1144 of 1800 (64%) male veterans for whom there were previous data. We tested a predictive latent variable path model of the relations between sociodemographic characteristics, predisaster physical and emotional health measures, and postdisaster emotional health and perceived earthquake impact. Perceived earthquake impact was predicted by predisaster emotional distress, functional limitations, and number of health conditions. Postdisaster emotional distress was predicted by preexisting emotional distress and earthquake impact. The regression coefficient from earthquake impact to postearthquake emotional distress was larger than that of the stability coefficient from preearthquake emotional distress. Postearthquake emotional distress also was affected indirectly by preearthquake emotional distress, health conditions, younger age, and lower socioeconomic status. The postdisaster emotional health of veterans who experienced greater earthquake impact would have likely benefited from postdisaster intervention, regardless of their predisaster emotional health. Younger veterans and veterans with generally poor physical and emotional health were more vulnerable to greater postearthquake emotional distress. Veterans of lower socioeconomic status were disproportionately likely to experience more effects of the disaster because they had more predisaster emotional distress, more functional

  18. Analysis of the Earthquake Impact towards water-based fire extinguishing system

    Science.gov (United States)

    Lee, J.; Hur, M.; Lee, K.

    2015-09-01

    Recently, extinguishing system installed in the building when the earthquake occurred at a separate performance requirements. Before the building collapsed during the earthquake, as a function to maintain a fire extinguishing. In particular, the automatic sprinkler fire extinguishing equipment, such as after a massive earthquake without damage to piping also must maintain confidentiality. In this study, an experiment installed in the building during the earthquake, the water-based fire extinguishing saw grasp the impact of the pipe. Experimental structures for water-based fire extinguishing seismic construction step by step, and then applied to the seismic experiment, the building appears in the extinguishing of the earthquake response of the pipe was measured. Construction of acceleration caused by vibration being added to the size and the size of the displacement is measured and compared with the data response of the pipe from the table, thereby extinguishing water piping need to enhance the seismic analysis. Define the seismic design category (SDC) for the four groups in the building structure with seismic criteria (KBC2009) designed according to the importance of the group and earthquake seismic intensity. The event of a real earthquake seismic analysis of Category A and Category B for the seismic design of buildings, the current fire-fighting facilities could have also determined that the seismic performance. In the case of seismic design categories C and D are installed in buildings to preserve the function of extinguishing the required level of seismic retrofit design is determined.

  19. The Key Role of Eyewitnesses in Rapid Impact Assessment of Global Earthquake

    Science.gov (United States)

    Bossu, R.; Steed, R.; Mazet-Roux, G.; Roussel, F.; Etivant, C.; Frobert, L.; Godey, S.

    2014-12-01

    Uncertainties in rapid impact assessments of global earthquakes are intrinsically large because they rely on 3 main elements (ground motion prediction models, building stock inventory and related vulnerability) which values and/or spatial variations are poorly constrained. Furthermore, variations of hypocentral location and magnitude within their respective uncertainty domain can lead to significantly different shaking level for centers of population and change the scope of the disaster. We present the strategy and methods implemented at the Euro-Med Seismological Centre (EMSC) to rapidly collect in-situ observations on earthquake effects from eyewitnesses for reducing uncertainties of rapid earthquake impact assessment. It comprises crowdsourced information (online questionnaires, pics) as well as information derived from real time analysis of web traffic (flashourcing technique), and more recently deployment of QCN (Quake Catcher Network) low cost sensors. We underline the importance of merging results of different methods to improve performances and reliability of collected data.We try to better understand and respond to public demands and expectations after earthquakes through improved information services and diversification of information tools (social networks, smartphone app., browsers adds-on…), which, in turn, drive more eyewitnesses to our services and improve data collection. We will notably present our LastQuake Twitter feed (Quakebot) and smartphone applications (IOs and android) which only report earthquakes that matter for the public and authorities, i.e. felt and damaging earthquakes identified thanks to citizen generated information.

  20. Control strategy to limit duty cycle impact of earthquakes on the LIGO gravitational-wave detectors

    Science.gov (United States)

    Biscans, S.; Warner, J.; Mittleman, R.; Buchanan, C.; Coughlin, M.; Evans, M.; Gabbard, H.; Harms, J.; Lantz, B.; Mukund, N.; Pele, A.; Pezerat, C.; Picart, P.; Radkins, H.; Shaffer, T.

    2018-03-01

    Advanced gravitational-wave detectors such as the laser interferometer gravitational-wave observatories (LIGO) require an unprecedented level of isolation from the ground. When in operation, they measure motion of less than 10‑19 m. Strong teleseismic events like earthquakes disrupt the proper functioning of the detectors, and result in a loss of data. An earthquake early-warning system, as well as a prediction model, have been developed to understand the impact of earthquakes on LIGO. This paper describes a control strategy to use this early-warning system to reduce the LIGO downtime by  ∼30%. It also presents a plan to implement this new earthquake configuration in the LIGO automation system.

  1. The psychological impact of a dual-disaster caused by earthquakes and radioactive contamination in Ichinoseki after the Great East Japan Earthquake.

    Science.gov (United States)

    Niitsu, Tomihisa; Takaoka, Kota; Uemura, Saho; Kono, Akiko; Saito, Akihiko; Kawakami, Norito; Nakazato, Michiko; Shimizu, Eiji

    2014-05-20

    The psychological impact of dual-disasters (earthquakes and a nuclear accident), on affected communities is unknown. This study investigated the impact of a dual-disaster (earthquakes and radioactive contamination) on the prevalence of psychological distress in a landlocked city within the Tohoku area, Japan. A cross-sectional mail-in survey with a random sample of inhabitants from Ichinoseki city was conducted eleven months after the disasters, and data from 902 respondents were analyzed by logistic regression models, with multiple imputation methodology. The K6 was used to determine psychological distress. The estimated prevalence of psychological distress was 48.0 percent. House damage due to earthquakes and anxiety about radioactive contamination were significantly associated with psychological distress (p earthquake and radioactive contamination appeared additive.

  2. Impact of intensity and loss assessment following the great Wenchuan Earthquake

    Science.gov (United States)

    Yuan, Yifan

    2008-09-01

    The great Wenchuan Earthquake occurred on May 12, 2008 in the Sichuan Province of China, and had a magnitude of 8.0. It is the most serious earthquake disaster in China since the great Tangshan Earthquake ( M s=7.8, July 28, 1976). According to official reports, there were 69,225 deaths, 379,640 injuries and 17,939 missing as of Aug. 11, 2008. The China Earthquake Administration quickly sent hundreds of experts to the field immediately after the event, to investigate the damage and assess the economic losses. This paper emphasizes the impact of seismic intensity and presents a preliminary loss assessment. A brief description of the geological features of the affected region is provided, followed by a summary of the earthquake damage. An isoseismal map is developed that shows that the high intensity region is distributed like a belt around the seimogenic fault, and that the epicentral intensity reached XI (Chinese Intensity Scale, similar to the Modified Mercalli Scale). The direct economic loss resulting from the earthquake is 692 billions RMB (about 100 billions US).

  3. Impact of average household income and damage exposure on post-earthquake distress and functioning: A community study following the February 2011 Christchurch earthquake.

    OpenAIRE

    Dorahy, Martin J.; Rowlands, Amy; Renouf, Charlotte; Hanna, Donncha; Britt, Eileen; Carter, Janet D.

    2015-01-01

    Post-traumatic stress, depression and anxiety symptoms are common outcomes following earthquakes, and may persist for months and years. This study systematically examined the impact of neighbourhood damage exposure and average household income on psychological distress and functioning in 600 residents of Christchurch, New Zealand, 4–6 months after the fatal February, 2011 earthquake. Participants were from highly affected and relatively unaffected suburbs in low, medium and high average house...

  4. Potential impacts of projected climate change on vegetation management in Hawai`i Volcanoes National Park

    Science.gov (United States)

    Camp, Richard J.; Loh, Rhonda; Berkowitz, S. Paul; Brinck, Kevin W.; Jacobi, James D.; Price, Jonathan; McDaniel, Sierra; Fortini, Lucas B.

    2018-01-01

    Climate change will likely alter the seasonal and annual patterns of rainfall and temperature in Hawai`i. This is a major concern for resource managers at Hawai`i Volcanoes National Park where intensely managed Special Ecological Areas (SEAs), focal sites for managing rare and endangered plants, may no longer provide suitable habitat under future climate. Expanding invasive species’ distributions also may pose a threat to areas where native plants currently predominate. We combine recent climate modeling efforts for the state of Hawai`i with plant species distribution models to forecast changes in biodiversity in SEAs under future climate conditions. Based on this bioclimatic envelope model, we generated projected species range maps for four snapshots in time (2000, 2040, 2070, and 2090) to assess whether the range of 39 native and invasive species of management interest are expected to contract, expand, or remain the same under a moderately warmer and more variable precipitation scenario. Approximately two-thirds of the modeled native species were projected to contract in range, while one-third were shown to increase. Most of the park’s SEAs were projected to lose a majority of the native species modeled. Nine of the 10 modeled invasive species were projected to contract within the park; this trend occurred in most SEAs, including those at low, middle, and high elevations. There was good congruence in the current (2000) distribution of species richness and SEA configuration; however, the congruence between species richness hotspots and SEAs diminished by the end of this century. Over time the projected species-rich hotspots increasingly occurred outside of current SEA boundaries. Our research brought together managers and scientists to increase understanding of potential climate change impacts, and provide needed information to address how plants may respond under future conditions relative to current managed areas.

  5. Impacting earthquake science and geoscience education: Educational programming to earthquake relocation

    Science.gov (United States)

    Carrick, Tina Louise

    This dissertation is comprised of four studies: three related to research on geoscience education and another seismological study of the South Island of New Zealand. The geoscience education research is grounded in 10 years of data collection and its implications for best practices for recruitment and retention of underrepresented minority students into higher education in the geosciences. The seismological component contains results from the relocation of earthquakes from the 2009 Dusky Sound Mw 7.8 event, South Island, New Zealand. In recent years, many have cited a major concern that U.S. is not producing enough STEM graduates to fit the forecasted economic need. This situation is exacerbated by the fact that underrepresented minorities are becoming a growing portion of the population, and people in these groups enter STEM careers at rates much smaller than their proportion of the populations. Among the STEM disciplines the Geosciences are the worst at attracting young people from underrepresented minorities. This dissertation reports on results the Pathways program at the University of Texas at El Paso Pathways which sought to create a geoscience recruitment and training network in El Paso, Texas to increase the number of Hispanic Americans students to attain higher degrees and increase the awareness of the geosciences from 2002-2012. Two elements of the program were a summer program for high school students and an undergraduate research program conducted during the academic year, called PREP. Data collected from pre- and post-surveys from the summer program showed statistically significant positive changes in attitudes towards the geosciences. Longitudinal data shows a strong positive correlation of the program with retention of participants in the geoscience pipeline. Results from the undergraduate research program show that it produced far more women and minority geoscience professionals than national norms. Combination of the institutional data, focus

  6. Earthquake Impact on Miami Haitian Americans: The Role of Family/Social Connectedness

    Science.gov (United States)

    Allen, Andrea; Marcelin, Louis Herns; Schmitz, Susan; Hausmann, Vicky; Shultz, James M.

    2012-01-01

    Individuals who are indirectly exposed to disasters may be affected psychologically. The impact of the 2010 Haiti earthquake reverberated throughout the Haitian American community in Miami, Florida. Many within the community held strong transnational family and friendship bonds to their homeland. We examined associations between indicators of…

  7. Social impacts of earthquakes caused by gas extraction in the Province of Groningen, The Netherlands

    NARCIS (Netherlands)

    van den Voort, Nick; Vanclay, Frank

    Gas extraction from the Groningen gasfield in the northern Netherlands has led to localized earthquakes which are projected to become more severe. The social impacts experienced by local residents include: damage to property; declining house prices; concerns about the chance of dykes breaking;

  8. USGS Earthquake Program GPS Use Case : Earthquake Early Warning

    Science.gov (United States)

    2015-03-12

    USGS GPS receiver use case. Item 1 - High Precision User (federal agency with Stafford Act hazard alert responsibilities for earthquakes, volcanoes and landslides nationwide). Item 2 - Description of Associated GPS Application(s): The USGS Eart...

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

    Directory of Open Access Journals (Sweden)

    GEORGE PARARAS-CARAYANNIS

    2011-06-01

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

  10. What Happened to Our Volcano?

    Science.gov (United States)

    Mangiante, Elaine Silva

    2006-01-01

    In this article, the author presents an investigative approach to "understanding Earth changes." The author states that students were familiar with earthquakes and volcanoes in other regions of the world but never considered how the land beneath their feet had experienced changes over time. Here, their geology unit helped them understand…

  11. Volcano Trial Case on GEP: Systematically processing EO data

    OpenAIRE

    Baumann, Andreas Bruno Graziano

    2017-01-01

    Volcanoes can be found all over the world; on land and below water surface. Even nowadays not all volcanoes are known. About 600 erupted in geologically recent times and about 50-70 volcanoes are currently active. Volcanoes can cause earthquakes; throw out blasts and tephras; release (toxic) gases; lava can flow relatively slow down the slopes; mass movements like debris avalanches, and landslides can cause tsunamis; and fast and hot pyroclastic surge, flows, and lahars can travel fast down ...

  12. Exploring hotspots of pneumococcal pneumonia and potential impacts of ejecta dust exposure following the Christchurch earthquakes.

    Science.gov (United States)

    Pearson, Amber L; Kingham, Simon; Mitchell, Peter; Apparicio, Philippe

    2013-12-01

    The etiology of pneumococcal pneumonia (PP) is well-known. Yet, some events may increase its incidence. Natural disasters may worsen air quality, a risk factor for PP. We investigated spatial/spatio-temporal clustering of PP pre- and post-earthquakes in Christchurch, New Zealand. The earthquakes resulted in deaths, widespread damage and liquefaction ejecta (a source of air-borne dust). We tested for clusters and associations with ejecta, using 97 cases (diagnosed 10/2008-12/2011), adjusted for age and area-level deprivation. The strongest evidence to support the potential role of ejecta in clusters of PP cases was the: (1) geographic shift in the spatio-temporal cluster after deprivation adjustment to match the post-earthquake clusters and; (2) increased relative risk in the fully-adjusted post-earthquake compared to the pre-earthquake cluster. The application of spatial statistics to study PP and ejecta are novel. Further studies to assess the long-term impacts of ejecta inhalation are recommended particularly in Christchurch, where seismic activity continues. Copyright © 2013 Elsevier Ltd. All rights reserved.

  13. Assessing the impact of Syrian refugees on earthquake fatality estimations in southeast Turkey

    Directory of Open Access Journals (Sweden)

    B. Wilson

    2018-01-01

    Full Text Available The influx of millions of Syrian refugees into Turkey has rapidly changed the population distribution along the Dead Sea Rift and East Anatolian fault zones. In contrast to other countries in the Middle East where refugees are accommodated in camp environments, the majority of displaced individuals in Turkey are integrated into local cities, towns, and villages – placing stress on urban settings and increasing potential exposure to strong earthquake shaking. Yet displaced populations are often unaccounted for in the census-based population models used in earthquake fatality estimations. This study creates a minimally modeled refugee gridded population model and analyzes its impact on semi-empirical fatality estimations across southeast Turkey. Daytime and nighttime fatality estimates were produced for five fault segments at earthquake magnitudes 5.8, 6.4, and 7.0. Baseline fatality estimates calculated from census-based population estimates for the study area varied in scale from tens to thousands of fatalities, with higher death totals in nighttime scenarios. Refugee fatality estimations were analyzed across 500 semi-random building occupancy distributions. Median fatality estimates for refugee populations added non-negligible contributions to earthquake fatalities at four of five fault locations, increasing total fatality estimates by 7–27 %. These findings communicate the necessity of incorporating refugee statistics into earthquake fatality estimations in southeast Turkey and the ongoing importance of placing environmental hazards in their appropriate regional and temporal context.

  14. Assessing the impact of Syrian refugees on earthquake fatality estimations in southeast Turkey

    Science.gov (United States)

    Wilson, Bradley; Paradise, Thomas

    2018-01-01

    The influx of millions of Syrian refugees into Turkey has rapidly changed the population distribution along the Dead Sea Rift and East Anatolian fault zones. In contrast to other countries in the Middle East where refugees are accommodated in camp environments, the majority of displaced individuals in Turkey are integrated into local cities, towns, and villages - placing stress on urban settings and increasing potential exposure to strong earthquake shaking. Yet displaced populations are often unaccounted for in the census-based population models used in earthquake fatality estimations. This study creates a minimally modeled refugee gridded population model and analyzes its impact on semi-empirical fatality estimations across southeast Turkey. Daytime and nighttime fatality estimates were produced for five fault segments at earthquake magnitudes 5.8, 6.4, and 7.0. Baseline fatality estimates calculated from census-based population estimates for the study area varied in scale from tens to thousands of fatalities, with higher death totals in nighttime scenarios. Refugee fatality estimations were analyzed across 500 semi-random building occupancy distributions. Median fatality estimates for refugee populations added non-negligible contributions to earthquake fatalities at four of five fault locations, increasing total fatality estimates by 7-27 %. These findings communicate the necessity of incorporating refugee statistics into earthquake fatality estimations in southeast Turkey and the ongoing importance of placing environmental hazards in their appropriate regional and temporal context.

  15. The impact of the Canterbury earthquakes on successful school leaving for adolescents.

    Science.gov (United States)

    Beaglehole, Ben; Bell, Caroline; Frampton, Christopher; Moor, Stephanie

    2017-02-01

    To examine the impact of the Canterbury earthquakes on the important adolescent transition period of school leaving. Local and national data on school leaving age, attainment of National Certificate of Educational Achievement (NCEA) standards, and school rolls (total registered students for schools) were examined to clarify long-term trends and delineate these from any impacts of the Canterbury earthquakes.  Results: Despite concerns about negative impacts, there was no evidence for increased school disengagement or poorer academic performance by students as a consequence of the earthquakes. Although there may have been negative effects for a minority, the possibility of post-disaster growth and resilience being the norm for the majority meant that negative effects on school leaving were not observed following the earthquakes. A range of post-disaster responses may have mitigated adverse effects on the adolescent population. Implications for Public Health: Overall long-term negative effects are unlikely for the affected adolescent population. The results also indicate that similar populations exposed to disasters in other settings are likely to do well in the presence of a comprehensive post-disaster response. © 2016 The Authors.

  16. Assessment of impact of strong earthquakes to the global economy by example of Thoku event

    Science.gov (United States)

    Tatiana, Skufina; Peter, Skuf'in; Sergey, Baranov; Vera, Samarina; Taisiya, Shatalova

    2016-04-01

    We examine the economic consequences of strong earthquakes by example of M9 Tahoku one that occurred on March 11, 2011 close to the northeast shore of Japanese coast Honshu. This earthquake became the strongest in the whole history of the seismological observations in this part of the planet. The generated tsunami killed more than 15,700 people, damaged 332,395 buildings and 2,126 roads. The total economic loss in Japan was estimated at 309 billion. The catastrophe in Japan also impacted global economy. To estimate its impact, we used regional and global stock indexes, production indexes, stock prices of the main Japanese, European and US companies, import and export dynamics, as well as the data provided by the custom of Japan. We also demonstrated that the catastrophe substantially affected the markets and on the short run in some indicators it even exceeded the effect of the global financial crisis of 2008. The last strong earthquake occurred in Nepal (25.04.2015, M7.8) and Chile (16.09.2015, M8.3), both actualized the research of cost assessments of the overall economic impact of seismic hazard. We concluded that it is necessary to treat strong earthquakes as one very important factor that affects the world economy depending on their location. The research was supported by Russian Foundation for Basic Research (Project 16-06-00056A).

  17. The impact of the Canterbury earthquakes on prescribing for mental health.

    Science.gov (United States)

    Beaglehole, Ben; Bell, Caroline; Frampton, Christopher; Hamilton, Greg; McKean, Andrew

    2015-08-01

    The aim of this study is to evaluate the impact of the Canterbury earthquakes on the mental health of the local population by examining prescribing patterns of psychotropic medication. Dispensing data from community pharmacies for antidepressants, antipsychotics, anxiolytics and sedatives/hypnotics are routinely recorded in a national database. The close relationship between prescribing and dispensing provides the opportunity to assess prescribing trends for Canterbury compared to national data and therefore examines the longitudinal impact of the earthquakes on prescribing patterns. Short-term increases in the use of anxiolytics and sedatives/hypnotics were observed after the most devastating February 2011 earthquake, but this effect was not sustained. There were no observable effects of the earthquakes on antidepressant or antipsychotic dispensing. Short-term increases in dispensing were only observed for the classes of anxiolytics and sedatives/hypnotics. No sustained changes in dispensing occurred. These findings suggest that long-term detrimental effects on the mental health of the Canterbury population were either not present or have not resulted in increased prescribing of psychotropic medication. © The Royal Australian and New Zealand College of Psychiatrists 2015.

  18. Earthquake Preparedness and Education: A Collective Impact Approach to Improving Awareness and Resiliency

    Science.gov (United States)

    Benthien, M. L.; Wood, M. M.; Ballmann, J. E.; DeGroot, R. M.

    2017-12-01

    The Southern California Earthquake Center (SCEC), headquartered at the University of Southern California, is a collaboration of more than 1000 scientists and students from 70+ institutions. SCEC's Communication, Education, and Outreach (CEO) program translates earthquake science into products and activities in order to increase scientific literacy, develop a diverse scientific workforce, and reduce earthquake risk to life and property. SCEC CEO staff coordinate these efforts through partnership collaborations it has established to engage subject matter experts, reduce duplication of effort, and achieve greater results. Several of SCEC's collaborative networks began within Southern California and have since grown statewide (Earthquake Country Alliance, a public-private-grassroots partnership), national ("EPIcenter" Network of museums, parks, libraries, etc.), and international (Great ShakeOut Earthquake Drills with millions of participants each year). These networks have benefitted greatly from partnerships with national (FEMA), state, and local emergency managers. Other activities leverage SCEC's networks in new ways and with national earth science organizations, such as the EarthConnections Program (with IRIS, NAGT, and many others), Quake Catcher Network (with IRIS) and the GeoHazards Messaging Collaboratory (with IRIS, UNAVCO, and USGS). Each of these partnerships share a commitment to service, collaborative development, and the application of research (including social science theory for motivating preparedness behaviors). SCEC CEO is developing new evaluative structures and adapting the Collective Impact framework to better understand what has worked well or what can be improved, according to the framework's five key elements: create a common agenda; share common indicators and measurement; engage diverse stakeholders to coordinate mutually reinforcing activities; initiate continuous communication; and provide "backbone" support. This presentation will provide

  19. Geology of kilauea volcano

    Science.gov (United States)

    Moore, R.B.; Trusdell, F.A.

    1993-01-01

    This paper summarizes studies of the structure, stratigraphy, petrology, drill holes, eruption frequency, and volcanic and seismic hazards of Kilauea volcano. All the volcano is discussed, but the focus is on its lower cast rift zone (LERZ) because active exploration for geothermal energy is concentrated in that area. Kilauea probably has several separate hydrothermal-convection systems that develop in response to the dynamic behavior of the volcano and the influx of abundant meteoric water. Important features of some of these hydrothermal-convection systems are known through studies of surface geology and drill holes. Observations of eruptions during the past two centuries, detailed geologic mapping, radiocarbon dating, and paleomagnetic secular-variation studies indicate that Kilauea has erupted frequently from its summit and two radial rift zones during Quaternary time. Petrologic studies have established that Kilauea erupts only tholeiitic basalt. Extensive ash deposits at Kilauea's summit and on its LERZ record locally violent, but temporary, disruptions of local hydrothermal-convection systems during the interaction of water or steam with magma. Recent drill holes on the LERZ provide data on the temperatures of the hydrothermal-convection systems, intensity of dike intrusion, porosity and permeability, and an increasing amount of hydrothermal alteration with depth. The prehistoric and historic record of volcanic and seismic activity indicates that magma will continue to be supplied to deep and shallow reservoirs beneath Kilauea's summit and rift zones and that the volcano will be affected by eruptions and earthquakes for many thousands of years. ?? 1993.

  20. Earthquake Early Warning Systems

    OpenAIRE

    Pei-Yang Lin

    2011-01-01

    Because of Taiwan’s unique geographical environment, earthquake disasters occur frequently in Taiwan. The Central Weather Bureau collated earthquake data from between 1901 and 2006 (Central Weather Bureau, 2007) and found that 97 earthquakes had occurred, of which, 52 resulted in casualties. The 921 Chichi Earthquake had the most profound impact. Because earthquakes have instant destructive power and current scientific technologies cannot provide precise early warnings in advance, earthquake ...

  1. Impact of earthquakes and their secondary environmental effects on public health

    Science.gov (United States)

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

    2017-04-01

    Earthquakes are among the most impressive geological processes with destructive effects on humans, nature and infrastructures. Secondary earthquake environmental effects (EEE) are induced by the ground shaking and are classified into ground cracks, slope movements, dust clouds, liquefactions, hydrological anomalies, tsunamis, trees shaking and jumping stones. Infectious diseases (ID) emerging during the post-earthquake period are considered as secondary earthquake effects on public health. This study involved an extensive and systematic literature review of 121 research publications related to the public health impact of 28 earthquakes from 1980 to 2015 with moment magnitude (Mw) from 6.1 to 9.2 and their secondary EEE including landslides, liquefaction and tsunamis generated in various tectonic environments (extensional, transform, compressional) around the world (21 events in Asia, 5 in America and one each in Oceania and Europe). The inclusion criteria were the literature type comprising journal articles and official reports, the natural disaster type including earthquakes and their secondary EEE (landslides, liquefaction, tsunamis), the population type including humans and the outcome measures characterized by disease incidence increase. The potential post-earthquake ID are classified into 14 groups including respiratory (detected after 15 of 28 earthquakes, 53.57%), water-borne (15, 53.57%), skin (8, 28.57%), vector-borne (8, 28.57%) wound-related (6, 21.43%), blood-borne (4, 14.29%), pulmonary (4, 14.29%), fecal-oral (3, 10.71%), food-borne (3, 10.71%), fungal (3, 10.71%), parasitic (3, 10.71%), eye (1, 3.57%), mite-borne (1, 3.57%) and soil-borne (1, 3.57%) infections. Based on age and genre data available for 15 earthquakes, the most vulnerable population groups are males, young children (age ≤ 10 years) and adults (age ≥ 65 years). Cholera, pneumonia and tetanus are the deadliest post-earthquake ID. The risk factors leading not only to disease

  2. Social impacts of earthquakes caused by gas extraction in the Province of Groningen, The Netherlands

    Energy Technology Data Exchange (ETDEWEB)

    Voort, Nick van der, E-mail: nickvdvoort@gmail.com; Vanclay, Frank, E-mail: frank.vanclay@rug.nl

    2015-01-15

    Gas extraction from the Groningen gasfield in the northern Netherlands has led to localised earthquakes which are projected to become more severe. The social impacts experienced by local residents include: damage to property; declining house prices; concerns about the chance of dykes breaking; feelings of anxiety and insecurity; health issues; and anger. These social and emotional impacts are exacerbated by the increasing distrust Groningen people have towards the national government and the gas company, NAM, a partnership between Shell and ExxonMobil. The earthquakes have reopened discussions about the distribution of benefits from gas production and the extent to which benefits are retained locally. Mitigation of the impacts is attempted, but the lack of trust decreases the effectiveness of the mitigation measures. The extent of this experience of previously-unforeseen, unanticipated impacts suggests that a new social and environmental impact assessment needs to be undertaken, and a new Social Impact Management Plan (SIMP) and Impacts and Benefits Agreement (IBA) developed, so that the project can regain its legitimacy and social licence to operate. In addition to conventional gas, this paper has wider relevance for unconventional gas developments, for example shale gas extraction by hydraulic fracturing methods (fracking). - Highlights: • Gas production in Groningen has caused over 1000 earthquakes. • The induced seismicity has caused many social impacts. • Impacts include building damage, reduced house prices, fear and health issues. • Mitigation measures attempted to date are inadequate. • Distrust towards the national government and operator hinders mitigation efforts. • Gas production in Groningen has lost its social licence to operate.

  3. Social impacts of earthquakes caused by gas extraction in the Province of Groningen, The Netherlands

    International Nuclear Information System (INIS)

    Voort, Nick van der; Vanclay, Frank

    2015-01-01

    Gas extraction from the Groningen gasfield in the northern Netherlands has led to localised earthquakes which are projected to become more severe. The social impacts experienced by local residents include: damage to property; declining house prices; concerns about the chance of dykes breaking; feelings of anxiety and insecurity; health issues; and anger. These social and emotional impacts are exacerbated by the increasing distrust Groningen people have towards the national government and the gas company, NAM, a partnership between Shell and ExxonMobil. The earthquakes have reopened discussions about the distribution of benefits from gas production and the extent to which benefits are retained locally. Mitigation of the impacts is attempted, but the lack of trust decreases the effectiveness of the mitigation measures. The extent of this experience of previously-unforeseen, unanticipated impacts suggests that a new social and environmental impact assessment needs to be undertaken, and a new Social Impact Management Plan (SIMP) and Impacts and Benefits Agreement (IBA) developed, so that the project can regain its legitimacy and social licence to operate. In addition to conventional gas, this paper has wider relevance for unconventional gas developments, for example shale gas extraction by hydraulic fracturing methods (fracking). - Highlights: • Gas production in Groningen has caused over 1000 earthquakes. • The induced seismicity has caused many social impacts. • Impacts include building damage, reduced house prices, fear and health issues. • Mitigation measures attempted to date are inadequate. • Distrust towards the national government and operator hinders mitigation efforts. • Gas production in Groningen has lost its social licence to operate

  4. Numerical simulations (2D) on the influence of pre-existing local structures and seismic source characteristics in earthquake-volcano interactions

    Science.gov (United States)

    Farías, Cristian; Galván, Boris; Miller, Stephen A.

    2017-09-01

    Earthquake triggering of hydrothermal and volcanic systems is ubiquitous, but the underlying processes driving these systems are not well-understood. We numerically investigate the influence of seismic wave interaction with volcanic systems simulated as a trapped, high-pressure fluid reservoir connected to a fluid-filled fault system in a 2-D poroelastic medium. Different orientations and earthquake magnitudes are studied to quantify dynamic and static stress, and pore pressure changes induced by a seismic event. Results show that although the response of the system is mainly dominated by characteristics of the radiated seismic waves, local structures can also play an important role on the system dynamics. The fluid reservoir affects the seismic wave front, distorts the static overpressure pattern induced by the earthquake, and concentrates the kinetic energy of the incoming wave on its boundaries. The static volumetric stress pattern inside the fault system is also affected by the local structures. Our results show that local faults play an important role in earthquake-volcanic systems dynamics by concentrating kinetic energy inside and acting as wave-guides that have a breakwater-like behavior. This generates sudden changes in pore pressure, volumetric expansion, and stress gradients. Local structures also influence the regional Coulomb yield function. Our results show that local structures affect the dynamics of volcanic and hydrothermal systems, and should be taken into account when investigating triggering of these systems from nearby or distant earthquakes.

  5. Impact of average household income and damage exposure on post-earthquake distress and functioning: A community study following the February 2011 Christchurch earthquake.

    Science.gov (United States)

    Dorahy, Martin J; Rowlands, Amy; Renouf, Charlotte; Hanna, Donncha; Britt, Eileen; Carter, Janet D

    2015-08-01

    Post-traumatic stress, depression and anxiety symptoms are common outcomes following earthquakes, and may persist for months and years. This study systematically examined the impact of neighbourhood damage exposure and average household income on psychological distress and functioning in 600 residents of Christchurch, New Zealand, 4-6 months after the fatal February, 2011 earthquake. Participants were from highly affected and relatively unaffected suburbs in low, medium and high average household income areas. The assessment battery included the Acute Stress Disorder Scale, the depression module of the Patient Health Questionnaire (PHQ-9), and the Generalized Anxiety Disorder Scale (GAD-7), along with single item measures of substance use, earthquake damage and impact, and disruptions in daily life and relationship functioning. Controlling for age, gender and social isolation, participants from low income areas were more likely to meet diagnostic cut-offs for depression and anxiety, and have more severe anxiety symptoms. Higher probabilities of acute stress, depression and anxiety diagnoses were evident in affected versus unaffected areas, and those in affected areas had more severe acute stress, depression and anxiety symptoms. An interaction between income and earthquake effect was found for depression, with those from the low and medium income affected suburbs more depressed. Those from low income areas were more likely, post-earthquake, to start psychiatric medication and increase smoking. There was a uniform increase in alcohol use across participants. Those from the low income affected suburb had greater general and relationship disruption post-quake. Average household income and damage exposure made unique contributions to earthquake-related distress and dysfunction. © 2014 The British Psychological Society.

  6. Long-term impact of earthquake stress on fasting glucose control and diabetes prevalence among Chinese adults of Tangshan.

    Science.gov (United States)

    An, Cuixia; Zhang, Yun; Yu, Lulu; Li, Na; Song, Mei; Wang, Lan; Zhao, Xiaochuan; Gao, Yuanyuan; Wang, Xueyi

    2014-01-01

    To investigate the long-term influence of stresses from the 1976 Tangshan earthquake on blood glucose control and the incidence of diabetes mellitus in Chinese people of Tangshan. 1,551 adults ≥ 37 years of age were recruited for this investigation in Tangshan city of China, where one of the deadliest earthquakes occurred in 1796. All subjects finished a questionnaire. 1,030 of them who experienced that earthquake were selected into the exposure group, while 521 were gathered as the control group who have not exposed to any earthquake. The numbers of subjects who were first identified with diabetes or had normal FBG but with diabetic history were added for the calculation of diabetes prevalence. Statistic-analysis was applied on the baseline data, and incidences of IFG as well as diabetes among all groups. Statistic comparisons indicate there is no significant difference on average fasting glucose levels between the control group and the exposure group. However, the prevalence of IFG and diabetes among the exposure group displays significant variance with the control group. The prevalence of diabetes among exposure groups is significantly higher than the control group. Women are more likely to have diabetes after experiencing earthquake stresses compared to men. The earthquake stress was linked to higher diabetes incidence as an independent factor. The earthquake stress has long-term impacts on diabetes incidence as an independent risk factor. Emerging and long-term managements regarding the care of IFG and diabetes in populations exposed to earthquake stress should be concerned.

  7. Environmental impact of the landslides caused by the 12 May 2008, Wenchuan, China earthquake

    Science.gov (United States)

    Highland, Lynn; Sun, Ping; Edited by Margottini, Claudio; Canuti, Paolo; Sassa, Kyoji

    2013-01-01

    The magnitude 7.9 (Mw) Wenchuan, China, earthquake of May 12, 2008 caused at least 88,000 deaths of which one third are estimated to be due to the more than 56,000 earthquake-induced landslides. The affected area is mountainous, featuring densely-vegetated, steep slopes through which narrowly confined rivers and streams flow. Numerous types of landslides occurred in the area, including rock avalanches, rock falls, translational and rotational slides, lateral spreads and debris flows. Some landslides mobilized hundreds of million cubic meters of material, often resulting in the damming of rivers and streams, impacting river ecosystems and morphology. Through an extensive search of both Chinese- and English-language publications we provide a summary of pertinent research on environmental effects, emphasizing key findings. Environmental effects caused by landslides include the alteration of agriculture, changes to natural ecosystems, changes in river morphology due to landslide dams and other effects such as sedimentation and flooding. Damage by landslides to the giant panda reserve infrastructure and habitat, was severe, threatening the survival of one of the world’s rarest species. The Panda reserves are of national significance to China, and to the vital tourism economy of the region. One of the major impacts to both the natural and built environment is the complete relocation of some human populations and infrastructure to new areas, resulting in the abandonment of towns and other areas that were damaged by the earthquake and landslides. The landslide effects have affected the biodiversity of the affected area, and it has been hypothesized that strict forest preservation measures taken in the years preceding the earthquake resulted in a reduction of the environmental damage to the area.

  8. Impact of a Large San Andreas Fault Earthquake on Tall Buildings in Southern California

    Science.gov (United States)

    Krishnan, S.; Ji, C.; Komatitsch, D.; Tromp, J.

    2004-12-01

    In 1857, an earthquake of magnitude 7.9 occurred on the San Andreas fault, starting at Parkfield and rupturing in a southeasterly direction for more than 300~km. Such a unilateral rupture produces significant directivity toward the San Fernando and Los Angeles basins. The strong shaking in the basins due to this earthquake would have had a significant long-period content (2--8~s). If such motions were to happen today, they could have a serious impact on tall buildings in Southern California. In order to study the effects of large San Andreas fault earthquakes on tall buildings in Southern California, we use the finite source of the magnitude 7.9 2001 Denali fault earthquake in Alaska and map it onto the San Andreas fault with the rupture originating at Parkfield and proceeding southward over a distance of 290~km. Using the SPECFEM3D spectral element seismic wave propagation code, we simulate a Denali-like earthquake on the San Andreas fault and compute ground motions at sites located on a grid with a 2.5--5.0~km spacing in the greater Southern California region. We subsequently analyze 3D structural models of an existing tall steel building designed in 1984 as well as one designed according to the current building code (Uniform Building Code, 1997) subjected to the computed ground motion. We use a sophisticated nonlinear building analysis program, FRAME3D, that has the ability to simulate damage in buildings due to three-component ground motion. We summarize the performance of these structural models on contour maps of carefully selected structural performance indices. This study could benefit the city in laying out emergency response strategies in the event of an earthquake on the San Andreas fault, in undertaking appropriate retrofit measures for tall buildings, and in formulating zoning regulations for new construction. In addition, the study would provide risk data associated with existing and new construction to insurance companies, real estate developers, and

  9. Impact of Short-term Changes In Earthquake Hazard on Risk In Christchurch, New Zealand

    Science.gov (United States)

    Nyst, M.

    2012-12-01

    The recent Mw 7.1, 4 September 2010 Darfield, and Mw 6.2, 22 February 2011 Christchurch, New Zealand earthquakes and the following aftershock activity completely changed the existing view on earthquake hazard of the Christchurch area. Not only have several faults been added to the New Zealand fault database, the main shocks were also followed by significant increases in seismicity due to high aftershock activity throughout the Christchurch region that is still on-going. Probabilistic seismic hazard assessment (PSHA) models take into account a stochastic event set, the full range of possible events that can cause damage or loss at a particular location. This allows insurance companies to look at their risk profiles via average annual losses (AAL) and loss-exceedance curves. The loss-exceedance curve is derived from the full suite of seismic events that could impact the insured exposure and plots the probability of exceeding a particular loss level over a certain period. Insurers manage their risk by focusing on a certain return period exceedance benchmark, typically between the 100 and 250 year return period loss level, and then reserve the amount of money needed to account for that return period loss level, their so called capacity. This component of risk management is not too sensitive to short-term changes in risk due to aftershock seismicity, as it is mostly dominated by longer-return period, larger magnitude, more damaging events. However, because the secondairy uncertainties are taken into account when calculating the exceedance probability, even the longer return period losses can still experience significant impact from the inclusion of time-dependent earthquake behavior. AAL is calculated by summing the product of the expected loss level and the annual rate for all events in the event set that cause damage or loss at a particular location. This relatively simple metric is an important factor in setting the annual premiums. By annualizing the expected losses

  10. When it happens again: impact of future San Francisco Bay area earthquakes

    Science.gov (United States)

    Zoback, M.; Boatwright, J.; Kornfield, L.; Scawthorn, C.; Rojahn, C.

    2005-12-01

    San Francisco Bay area earthquakes, like major floods and hurricanes, have the potential for massive damage to dense urban population centers concentrated in vulnerable zones-along active faults, in coastal regions, and along major river arteries. The recent destruction of Hurricane Katrina does have precedent in the destruction following the 1906 "San Francisco" earthquake and fire in which more than 3000 people were killed and 225,000 were left homeless in San Francisco alone, a city of 400,000 at the time. Analysis of a comprehensive set of damage reports from the magnitude (M) 7.9 1906 earthquake indicates a region of ~ 18,000 km2 was subjected to shaking of Modified Mercalli Intensity of VIII or more - motions capable of damaging even modern, well-built structures; more than 60,000 km2 was subjected to shaking of Intensity VII or greater - the threshold for damage to masonry and poorly designed structures. By comparison, Katrina's hurricane force winds and intense rainfall impacted an area of ~100,000 km2 on the Gulf Coast. Thus, the anticipated effects of a future major Bay Area quake to lives, property, and infrastructure are comparable in scale to Katrina. Secondary hazards (levee failure and flooding in the case of Katrina and fire following the 1906 earthquake) greatly compounded the devastation in both disasters. A recent USGS-led study concluded there is a 62% chance of one or more damaging (M6.7 or greater) earthquakes striking the greater San Francisco Bay area over the next 30 years. The USGS prepared HAZUS loss estimates for the 10 most likely forecast earthquakes which range in size from a M6.7 event on a blind thrust to the largest anticipated event, a M7.9 repeat of the 1906 earthquake. The largest economic loss is expected for a repeat of the 1906 quake. Losses in the Bay region for this event are nearly double those predicted for a M6.9 rupture of the entire Hayward Fault in the East Bay. However, because of high density of population along the

  11. What Are Volcano Hazards?

    Science.gov (United States)

    ... Sheet 002-97 Revised March 2008 What Are Volcano Hazards? Volcanoes give rise to numerous geologic and ... as far as 15 miles from the volcano. Volcano Landslides A landslide or debris avalanche is a ...

  12. Geology of Kilauea volcano

    Energy Technology Data Exchange (ETDEWEB)

    Moore, R.B. (Geological Survey, Denver, CO (United States). Federal Center); Trusdell, F.A. (Geological Survey, Hawaii National Park, HI (United States). Hawaiian Volcano Observatory)

    1993-08-01

    This paper summarizes studies of the structure, stratigraphy, petrology, drill holes, eruption frequency, and volcanic and seismic hazards of Kilauea volcano. All the volcano is discussed, but the focus is on its lower east rift zone (LERZ) because active exploration for geothermal energy is concentrated in that area. Kilauea probably has several separate hydrothermal-convection systems that develop in response to the dynamic behavior of the volcano and the influx of abundant meteoric water. Important features of some of these hydrothermal-convection systems are known through studies of surface geology and drill holes. Observations of eruptions during the past two centuries, detailed geologic mapping, radiocarbon dating, and paleomagnetic secular-variation studies indicate that Kilauea has erupted frequently from its summit and two radial rift zones during Quaternary time. Petrologic studies have established that Kilauea erupts only tholeiitic basalt. Extensive ash deposits at Kilauea's summit and on its LERZ record locally violent, but temporary, disruptions of local hydrothermal-convection systems during the interaction of water or steam with magma. Recent drill holes on the LERZ provide data on the temperatures of the hydrothermal-convection systems, intensity of dike intrusion, porosity and permeability, and an increasing amount of hydrothermal alteration with depth. The prehistoric and historic record of volcanic and seismic activity indicates that magma will continue to be supplied to deep and shallow reservoirs beneath Kilauea's summit and rift zones and that the volcano will be affected by eruptions and earthquakes for many thousands of years. 71 refs., 2 figs.

  13. The Impact of The Energy-time Distribution of The Ms 7.0 Lushan Earthquake on Slope Dynamic Reliability

    Science.gov (United States)

    Liu, X.; Griffiths, D.; Tang, H.

    2013-12-01

    This paper introduces a new method to evaluate the area-specific potential risk for earthquake induced slope failures, and the Lushan earthquake is used as an example. The overall framework of this paper consists of three parts. First, the energy-time distribution of the earthquake was analyzed. The Ms 7.0 Lushan earthquake occurred on April 20, 2013. The epicenter was located in Lushan County, Sichuan province, which is in the same province heavily impacted by the 2008 Ms 8.0 Wenchuan earthquake. Compared with the Wenchuan earthquake, the records of the strong motion of the Lushan earthquake are much richer than those of the Wenchuan earthquake. Some earthquake observatories are very close to the epicenter and the closest strong motion record was collected with a spherical distance of just 34.8 km from the epicenter. This advantage stems from the fact that routine efforts of strong motion observation in this area were greatly enhanced after the Wenchuan earthquake. The energy-time distribution features of the Lushan earthquake waves were obtained from 123 groups of three-component acceleration records of the 40-second mainshock. When the 5% ~ 85% energy section is taken into account, the significant duration is presented with a start point of the first 3.0 to 4.0 seconds and the end point of the first 13.0 to 15.0 seconds. However, if the acceleration of 0.15g is taken into account, the bracketed duration is obtained with the start point of the first 4.0 to 5.0 seconds and the end point of the first 13.0 to 14.0 seconds. Second, a new reliability analysis method was proposed which considers the energy-time distribution of the earthquake. Using the significant duration and bracketed duration as certain statistical windows, the advantages of considering energy-time distribution can be involved. In this method, the dynamic critical slip surfaces and their factors of safety (FOS) are described as time series. The slope reliability evaluation criteria, such as dynamic

  14. Environmental risk evaluation to minimize impacts within the area affected by the Wenchuan earthquake

    International Nuclear Information System (INIS)

    Du, Pengfei; Chen, Jining; Chen, Chao; Liu, Yi; Liu, Jianguo; Wang, Hongtao; Zhang, Xiaojian

    2012-01-01

    Earthquakes can be devastating to built infrastructure and the natural environment, as evidenced by the March 2011, M = 9.0 earthquake, and subsequent tsunami, in Japan. As seen in the Japanese event, environmental damage caused by secondary disasters (tsunami, leakage from a nuclear reactor) can equal or exceed the impacts of the primary event. In order to develop an environmental assessment system to examine secondary disasters, a comprehensive environmental impact evaluation was conducted after the Wenchuan earthquake that occurred on 12 May 2008 in the Sichuan Province, China. This evaluation focused on several key environmental elements such as wastewater, drinking water, soil, solid waste, radiation, and ecosystem-level effects. As part of this assessment, an analysis of root causes and potential solutions was conducted for key issues such as population relocation and resettlement in temporary dwellings, recovery of environmental protection functions, industrial development strategies and production recovery. Methods for post-quake environmental assessment were developed, utilizing GIS-based techniques for spatial evaluation of primary and secondary disaster patterns. The goal of this exercise was the development of effective assessment methods that can be rapidly applied in a post-disaster situation to reduce and mitigate damage caused by secondary disasters, and facilitate the recovery of impaired environmental management structure and function. - Highlights: ► A comprehensive post-quake environmental risk evaluation system was developed. ► The research identifies potential long-term environmental risks in many aspects. ► The research analyzes potential solutions for many typical post-disaster issues. ► Effective assessment methods can be applied in a post-disaster situation to reduce damage caused by secondary disasters.

  15. Environmental risk evaluation to minimize impacts within the area affected by the Wenchuan earthquake

    Energy Technology Data Exchange (ETDEWEB)

    Du, Pengfei, E-mail: dupf@tsinghua.edu.cn; Chen, Jining, E-mail: jchen1@tsinghua.edu.cn; Chen, Chao, E-mail: chen_water@tsinghua.edu.cn; Liu, Yi, E-mail: yi.liu@tsinghua.edu.cn; Liu, Jianguo, E-mail: jgliu@tsinghua.edu.cn; Wang, Hongtao, E-mail: htwang@tsinghua.edu.cn; Zhang, Xiaojian, E-mail: zhangxj@tsinghua.edu.cn

    2012-03-01

    Earthquakes can be devastating to built infrastructure and the natural environment, as evidenced by the March 2011, M = 9.0 earthquake, and subsequent tsunami, in Japan. As seen in the Japanese event, environmental damage caused by secondary disasters (tsunami, leakage from a nuclear reactor) can equal or exceed the impacts of the primary event. In order to develop an environmental assessment system to examine secondary disasters, a comprehensive environmental impact evaluation was conducted after the Wenchuan earthquake that occurred on 12 May 2008 in the Sichuan Province, China. This evaluation focused on several key environmental elements such as wastewater, drinking water, soil, solid waste, radiation, and ecosystem-level effects. As part of this assessment, an analysis of root causes and potential solutions was conducted for key issues such as population relocation and resettlement in temporary dwellings, recovery of environmental protection functions, industrial development strategies and production recovery. Methods for post-quake environmental assessment were developed, utilizing GIS-based techniques for spatial evaluation of primary and secondary disaster patterns. The goal of this exercise was the development of effective assessment methods that can be rapidly applied in a post-disaster situation to reduce and mitigate damage caused by secondary disasters, and facilitate the recovery of impaired environmental management structure and function. - Highlights: Black-Right-Pointing-Pointer A comprehensive post-quake environmental risk evaluation system was developed. Black-Right-Pointing-Pointer The research identifies potential long-term environmental risks in many aspects. Black-Right-Pointing-Pointer The research analyzes potential solutions for many typical post-disaster issues. Black-Right-Pointing-Pointer Effective assessment methods can be applied in a post-disaster situation to reduce damage caused by secondary disasters.

  16. Mauna Kea volcano's ongoing 18-year swarm

    Science.gov (United States)

    Wech, A.; Thelen, W. A.

    2017-12-01

    Mauna Kea is a large postshield-stage volcano that forms the highest peak on Hawaii Island. The 4,205-meter high volcano erupted most recently between 6,000 and 4,500 years ago and exhibits relatively low rates of seismicity, which are mostly tectonic in origin resulting from lithospheric flexure under the weight of the volcano. Here we identify deep repeating earthquakes occurring beneath the summit of Mauna Kea. These earthquakes, which are not part of the Hawaiian Volcano Observatory's regional network catalog, were initially detected through a systematic search for coherent seismicity using envelope cross-correlation, and subsequent analysis revealed the presence of a long-term, ongoing swarm. The events have energy concentrated at 2-7 Hz, and can be seen in filtered waveforms dating back to the earliest continuous data from a single station archived at IRIS from November 1999. We use a single-station (3 component) match-filter analysis to create a catalog of the repeating earthquakes for the past 18 years. Using two templates created through phase-weighted stacking of thousands of sta/lta-triggers, we find hundreds of thousands of M1.3-1.6 earthquakes repeating every 7-12 minutes throughout this entire time period, with many smaller events occurring in between. The earthquakes occur at 28-31 km depth directly beneath the summit within a conspicuous gap in seismicity surrounding the flanks of the volcano. Magnitudes and periodicity are remarkably stable long-term, but do exhibit slight variability and occasionally display higher variability on shorter time scales. Network geometry precludes obtaining a reliable focal mechanism, but we interpret the frequency content and hypocenters to infer a volcanic source distinct from the regional tectonic seismicity responding to the load of the island. In this model, the earthquakes may result from the slow, persistent degassing of a relic magma chamber at depth.

  17. The Terminator Time in subionospheric VLF/LF diurnal variation as recorded by the Romanian VLF/LF radio monitoring system related to earthquake occurrence and volcano erruptions

    Science.gov (United States)

    Moldovan, I. A.; Moldovan, A. S.; Biagi, P. F.; Ionescu, C.; Schwingenschuh, K.; Boudjada, M. Y.

    2012-04-01

    The Romanian VLF/LF monitoring system consisting in a radio receiver and the infrastructure that is necessary to record and transmit the collected data is part of the European international network named INFREP. Information on electromagnetic fields' intensities created by transmitters at a receiving site are indicating the quality of the propagation along the paths between the receivers and transmitters. Studying the ionosphere's influences on the electromagnetic waves' propagation along a certain path is a method to put into evidence possible modifications of its lower structure and composition as earthquakes' precursors. The VLF/LF receiver installed in Romania was put into operation in February 2009 and has already 3 years of testing, functioning and proving its utility in the forecast of some earthquakes or volcanic eruptions. Simultaneously we monitor, in the same site with the VLF/LF receiver, the vertical atmospheric electric field and different other meteorological parameters as: temperature, pressure or rainfall. The global magnetic conditions are emphasized with the help of Daily Geomagnetic Index Kp. At a basic level, the adopted analysis consists in a simple statistical evaluation of the signals by comparing the instantaneous values to the trend of the signal. In this paper we pay attention to the terminator times in subionospheric VLF/LF diurnal variation, which are defined as the times of minimum in amplitude (or phase) around sunrise and sunset. These terminator times are found to shift significantly just around the earthquake. In the case of Kobe earthquake, there were found significant shifts in both morning and evening terminator times and these authors interpreted the shift in terminator time in terms of the lowering of lower ionosphere by using the full-wave mode theory. A LabVIEW application which accesses the VLF/LF receiver through internet was developed. This program opens the receiver's web-page and automatically retrieves the list of data

  18. The 2008 Eruption of Chaitén Volcano, Chile and National Volcano-Monitoring Programs in the U.S. and Chile

    Science.gov (United States)

    Ewert, J. W.; Lara, L. E.; Moreno, H.

    2008-12-01

    Chaitén volcano, southern Chile, began erupting on 2 May 2008. The eruption produced 3 Plinian eruption pulses between May 2 and 8. Between Plinian phases the volcano emitted a constant column of ash to approximately 10 km, gradually diminishing to approximately 3 km by the end of June. The eruption of Chaitén was remarkable on several counts--it was the first rhyolite eruption on the planet since Novarupta (Katmai) erupted in 1912, and Chaitén had apparently lain dormant for approximately 9300 years. Though Chaitén is located in a generally sparsely populated region, the eruption had widespread impacts. More than 5000 people had to be quickly evacuated from proximal areas and aviation in southern South America was disrupted for weeks. Within 10 days secondary lahars had overrun much of the town of Chaitén complicating the prospects of the townspeople to return to their homes. Prior to the eruption onset, the nearest real-time seismic station was 300 km distant, and earthquakes were not felt by local citizens until approximately 30 hours before the eruption onset. No other signs of unrest were noted. Owing to the lack of near-field monitoring, and the nighttime eruption onset, there was initial confusion about which volcano was erupting: Chaitén or nearby Michinmahuida. Lack of monitoring systems at Chaitén meant that warning time for the public at risk was extremely short, and owing to the nature of the eruption and the physical geography of the area, it was very difficult to install monitoring instruments to track its progress after the eruption started. The lack of geophysical monitoring also means that an important data set on precursory behavior for silicic systems was not collected. With more than 120 Pleistocene to Holocene-age volcanoes within its continental territory, Chile is one of the more volcanically active countries in the world. The eruption of Chaitén has catalyzed the creation of a new program within the Servicio Nacional de Geología y

  19. Probing magma reservoirs to improve volcano forecasts

    Science.gov (United States)

    Lowenstern, Jacob B.; Sisson, Thomas W.; Hurwitz, Shaul

    2017-01-01

    When it comes to forecasting eruptions, volcano observatories rely mostly on real-time signals from earthquakes, ground deformation, and gas discharge, combined with probabilistic assessments based on past behavior [Sparks and Cashman, 2017]. There is comparatively less reliance on geophysical and petrological understanding of subsurface magma reservoirs.

  20. Volcano seismology

    Science.gov (United States)

    Chouet, B.

    2003-01-01

    A fundamental goal of volcano seismology is to understand active magmatic systems, to characterize the configuration of such systems, and to determine the extent and evolution of source regions of magmatic energy. Such understanding is critical to our assessment of eruptive behavior and its hazardous impacts. With the emergence of portable broadband seismic instrumentation, availability of digital networks with wide dynamic range, and development of new powerful analysis techniques, rapid progress is being made toward a synthesis of high-quality seismic data to develop a coherent model of eruption mechanics. Examples of recent advances are: (1) high-resolution tomography to image subsurface volcanic structures at scales of a few hundred meters; (2) use of small-aperture seismic antennas to map the spatio-temporal properties of long-period (LP) seismicity; (3) moment tensor inversions of very-long-period (VLP) data to derive the source geometry and mass-transport budget of magmatic fluids; (4) spectral analyses of LP events to determine the acoustic properties of magmatic and associated hydrothermal fluids; and (5) experimental modeling of the source dynamics of volcanic tremor. These promising advances provide new insights into the mechanical properties of volcanic fluids and subvolcanic mass-transport dynamics. As new seismic methods refine our understanding of seismic sources, and geochemical methods better constrain mass balance and magma behavior, we face new challenges in elucidating the physico-chemical processes that cause volcanic unrest and its seismic and gas-discharge manifestations. Much work remains to be done toward a synthesis of seismological, geochemical, and petrological observations into an integrated model of volcanic behavior. Future important goals must include: (1) interpreting the key types of magma movement, degassing and boiling events that produce characteristic seismic phenomena; (2) characterizing multiphase fluids in subvolcanic

  1. Earthquake impact on settlements: the role of urban and structural morphology

    Science.gov (United States)

    Bostenaru Dan, M.; Armas, I.

    2015-10-01

    This study is aimed to create an alternative to the classical GIS representation of the impact of earthquake hazards on urban areas. To accomplish this, the traditional map was revised, so that it can cope with contemporary innovative ways of planning, namely strategic planning. As in the theory of fractals, the building dimension and the urban neighbourhood dimension are addressed as different geographic scales between which lessons for decisions can be learned through regression. The interaction between the two scales is useful when looking for alternatives, for the completion of a GIS analysis, and in choosing the landmarks, which, in the case of hazards, become strategic elements in strategic planning. A methodology to innovate mapping as a digital means for analysing and visualising the impact of hazards is proposed. This method relies on concepts from various geography, urban planning, structural engineering and architecture approaches related to disaster management. The method has been tested at the building scale for the N-S Boulevard in Bucharest, Romania, called Magheru. At the urban scale, an incident database has been created, in which the case study for the building level can be mapped. The paper presented is part of a larger research work, which addresses decision making using the framework shown here. The main value of the paper is in proposing a conceptual framework to deconstruct the map for digital earthquake disaster impact analysis and representation. The originality of the concept consists in the representation of elements at different scales considered to be of different levels of importance in the urban tissue, according to the analysis to be performed on them.

  2. The impacts of pyroclastic surges on buildings at the eruption of the Soufrière Hills volcano, Montserrat

    Science.gov (United States)

    Baxter, Peter J.; Boyle, Robin; Cole, Paul; Neri, Augusto; Spence, Robin; Zuccaro, Giulio

    2005-04-01

    We investigated the impacts on buildings of three pyroclastic surges that struck three separate villages on 25 June, 21 September and 26 December, 1997, during the course of the andesitic dome building eruption of the Soufrière Hills Volcano, Montserrat, which began on 18 July, 1995. A detailed analysis of the building damage of the 26 December event was used to compare the findings on the flow and behaviour of dilute pyroclastic density currents (PDCs) with the classical reports of PDCs from historical eruptions of similar size. The main characteristics of the PDC, as inferred from the building damage, were the lateral loading and directionality of the current; the impacts corresponded to the dynamic pressure of the PDC, with a relatively slow rate of rise and without the peak overpressure or a shock front associated with explosive blast; and the entrainment of missiles and ground materials which greatly added to the destructiveness of the PDC. The high temperature of the ash, causing the rapid ignition of furniture and other combustibles, was a major cause of damage even where the dynamic pressure was low at the periphery of the current. The vulnerability of buildings lay in the openings, mainly windows, which allowed the current to enter the building envelope, and in the flammable contents, as well as the lack of resistance to the intense heat and dynamic pressure of some types of vernacular building construction, such as wooden chattel houses, rubble masonry walls and galvanised steel-sheet roofs. Marked variability in the level of damage due to dynamic pressure (in a range 1-5 kPa, or more) was evident throughout most of the impact area, except for the zone of total loss, and this was attributable to the effects of topography and sheltering, and projectiles, and probably localised variations in current velocity and density. A marked velocity gradient existed from the outer part to the central axis of the PDC, where buildings and vegetation were razed to the

  3. Characteristics of Hawaiian volcanoes

    Science.gov (United States)

    Poland, Michael P.; Takahashi, T. Jane; Landowski, Claire M.

    2014-01-01

    Founded in 1912 at the edge of the caldera of Kīlauea Volcano, HVO was the vision of Thomas A. Jaggar, Jr., a geologist from the Massachusetts Institute of Technology, whose studies of natural disasters around the world had convinced him that systematic, continuous observations of seismic and volcanic activity were needed to better understand—and potentially predict—earthquakes and volcanic eruptions. Jaggar summarized the aim of HVO by stating that “the work should be humanitarian” and have the goals of developing “prediction and methods of protecting life and property on the basis of sound scientific achievement.” These goals align well with those of the USGS, whose mission is to serve the Nation by providing reliable scientific information to describe and understand the Earth; minimize loss of life and property from natural disasters; manage natural resources; and enhance and protect our quality of life.

  4. The Impact of a Natural Disaster: Under- and Postgraduate Nursing Education Following the Canterbury, New Zealand, Earthquake Experiences

    Science.gov (United States)

    Richardson, S. K.; Richardson, A.; Trip, H.; Tabakakis, K.; Josland, H.; Maskill, V.; Dolan, B.; Hickmott, B.; Houston, G.; Cowan, L.; McKay, L.

    2015-01-01

    While natural disasters have been reported internationally in relation to the injury burden, role of rescuers and responders, there is little known about the impact on education in adult professional populations. A 7.1 magnitude earthquake affected the Canterbury region of New Zealand on 4 September 2010 followed by more than 13,000 aftershocks in…

  5. Quantifying the humanitarian and economic impact of earthquakes on South American capital cities (Invited)

    Science.gov (United States)

    Zoback, M. L.; Cabrera, C.; Pomonis, A.; Baca, A.; Brunner, I.; Cheung, G.; Chen, A.; Nagel, B.; Carrasco, S.

    2009-12-01

    By 2000, an estimated 80% of South America’s population lived in urban areas (Veblen et al., The Physical Geography of South America, Oxford University Press, 2007). A significant fraction of those urban dwellers resides in the capital cities which are major economic centers and act as magnets for rural poor and refugees. This population concentration includes many residents living in extreme poverty in substandard and informal housing, often on the margins of these capital cities and sometimes on steep slopes, greatly compounding the vulnerability to natural hazards. We are analyzing the humanitarian and economic risk for six of the seismically most-at-risk South American capitals along the northern and western plate boundaries of South America: Caracas, Venezuela; Bogotá, Colombia; Quito, Ecuador; Lima, Perú; La Paz, Bolivia; and Santiago, Chile. Impacts are provided in the form of expected losses for a specific “likely” scenario earthquake and in a probabilistic format using exceedance probability curves (probability of exceeding a given loss in different return periods). Impacts to be quantified include: total economic losses, potential fatalities, potential serious injuries, and the number of displaced households. Probabilistic seismic hazard was developed in collaboration with numerous South American experts and includes subduction interface, intraslab, background crustal and, where available, active fault sources. A significant challenge for this study is to accurately account for the exposure and vulnerability of populations living in the informal, shanty areas. Combining analysis of aerial imagery and on-the-ground reconnaissance, we define between 20-30 “inventory districts” of relatively uniform construction styles within each capital. Statistical distributions of the different construction types and their characteristics (height, occupancy, year built, average value) are estimated for each district. In addition, working with local graduate

  6. The threat of silent earthquakes

    Science.gov (United States)

    Cervelli, Peter

    2004-01-01

    Not all earthquakes shake the ground. The so-called silent types are forcing scientists to rethink their understanding of the way quake-prone faults behave. In rare instances, silent earthquakes that occur along the flakes of seaside volcanoes may cascade into monstrous landslides that crash into the sea and trigger towering tsunamis. Silent earthquakes that take place within fault zones created by one tectonic plate diving under another may increase the chance of ground-shaking shocks. In other locations, however, silent slip may decrease the likelihood of destructive quakes, because they release stress along faults that might otherwise seem ready to snap.

  7. Impact of the great east Japan earthquake on the body mass index of preschool children: a nationwide nursery school survey

    Science.gov (United States)

    Yokomichi, Hiroshi; Zheng, Wei; Matsubara, Hiroko; Ishikuro, Mami; Kikuya, Masahiro; Isojima, Tsuyoshi; Yokoya, Susumu; Tanaka, Toshiaki; Kato, Noriko; Chida, Shoichi; Ono, Atsushi; Hosoya, Mitsuaki; Tanaka, Soichiro; Kuriyama, Shinichi; Kure, Shigeo; Yamagata, Zentaro

    2016-01-01

    Objective To evaluate the impact of the 2011 great east Japan earthquake on body mass index (BMI) of preschool children. Design Retrospective cohort study and ecological study. Setting Affected prefectures (Fukushima, Miyagi and Iwate) and unaffected prefectures in northeast Japan. Participants The cohort study assessed 2033 and 1707 boys and 1909 and 1658 girls in 3 affected prefectures and unaffected prefectures, respectively, all aged 3–4 years at the time of the earthquake. The ecological study examined random samples of schoolchildren from the affected prefectures. Primary and secondary outcome measures The cohort study compared postdisaster changes in BMIs and the prevalence of overweight and obese children. The ecological study evaluated postdisaster changes in the prevalence of overweight children. Results 1 month after the earthquake, significantly increased BMIs were observed among girls (+0.087 kg/m2 vs unaffected prefectures) in Fukushima and among boys and girls (+0.165 and +0.124 kg/m2, respectively vs unaffected prefectures) in Iwate. 19 months after the earthquake, significantly increased BMIs were detected among boys and girls (+0.137 and +0.200 kg/m2, respectively vs unaffected prefectures) in Fukushima, whereas significantly decreased BMIs were observed among boys and girls (−0.218 and −0.082 kg/m2, respectively vs unaffected prefectures) in Miyagi. 1 month after the earthquake, Fukushima, Miyagi and Iwate had a slightly increased prevalence of overweight boys, whereas Fukushima had a slightly decreased prevalence of overweight girls, compared with the unaffected prefectures. The ecological study detected increases in the prevalence of overweight boys and girls in Fukushima who were 6–11 and 6–10 years of age, respectively. Conclusions These results suggest that in the affected prefectures, preschool children gained weight immediately after the earthquake. The long-term impact of the earthquake on early childhood

  8. Impact of the great east Japan earthquake on the body mass index of preschool children: a nationwide nursery school survey.

    Science.gov (United States)

    Yokomichi, Hiroshi; Zheng, Wei; Matsubara, Hiroko; Ishikuro, Mami; Kikuya, Masahiro; Isojima, Tsuyoshi; Yokoya, Susumu; Tanaka, Toshiaki; Kato, Noriko; Chida, Shoichi; Ono, Atsushi; Hosoya, Mitsuaki; Tanaka, Soichiro; Kuriyama, Shinichi; Kure, Shigeo; Yamagata, Zentaro

    2016-04-07

    To evaluate the impact of the 2011 great east Japan earthquake on body mass index (BMI) of preschool children. Retrospective cohort study and ecological study. Affected prefectures (Fukushima, Miyagi and Iwate) and unaffected prefectures in northeast Japan. The cohort study assessed 2033 and 1707 boys and 1909 and 1658 girls in 3 affected prefectures and unaffected prefectures, respectively, all aged 3-4 years at the time of the earthquake. The ecological study examined random samples of schoolchildren from the affected prefectures. The cohort study compared postdisaster changes in BMIs and the prevalence of overweight and obese children. The ecological study evaluated postdisaster changes in the prevalence of overweight children. 1 month after the earthquake, significantly increased BMIs were observed among girls (+0.087 kg/m(2) vs unaffected prefectures) in Fukushima and among boys and girls (+0.165 and +0.124 kg/m(2), respectively vs unaffected prefectures) in Iwate. 19 months after the earthquake, significantly increased BMIs were detected among boys and girls (+0.137 and +0.200 kg/m(2), respectively vs unaffected prefectures) in Fukushima, whereas significantly decreased BMIs were observed among boys and girls (-0.218 and -0.082 kg/m(2), respectively vs unaffected prefectures) in Miyagi. 1 month after the earthquake, Fukushima, Miyagi and Iwate had a slightly increased prevalence of overweight boys, whereas Fukushima had a slightly decreased prevalence of overweight girls, compared with the unaffected prefectures. The ecological study detected increases in the prevalence of overweight boys and girls in Fukushima who were 6-11 and 6-10 years of age, respectively. These results suggest that in the affected prefectures, preschool children gained weight immediately after the earthquake. The long-term impact of the earthquake on early childhood growth was more variable among the affected prefectures, possibly as a result of different speeds of

  9. Volcano-tectonic interactions at Sabancaya and other Peruvian volcanoes revealed by InSAR and seismicity

    Science.gov (United States)

    Jay, J.; Pritchard, M. E.; Aron, F.; Delgado, F.; Macedo, O.; Aguilar, V.

    2013-12-01

    An InSAR survey of all 13 Holocene volcanoes in the Andean Central Volcanic Zone of Peru reveals previously undocumented surface deformation that is occasionally accompanied by seismic activity. Our survey utilizes SAR data spanning from 1992 to the present from the ERS-1, ERS-2, and Envisat satellites, as well as selected data from the TerraSAR-X satellite. We find that the recent unrest at Sabancaya volcano (heightened seismicity since 22 February 2013 and increased fumarolic output) has been accompanied by surface deformation. We also find two distinct deformation episodes near Sabancaya that are likely associated with an earthquake swarm in February 2013 and a M6 normal fault earthquake that occurred on 17 July 2013. Preliminary modeling suggests that faulting from the observed seismic moment can account for nearly all of the observed deformation and thus we have not yet found clear evidence for recent magma intrusion. We also document an earlier episode of deformation that occurred between December 2002 and September 2003 which may be associated with a M5.3 earthquake that occurred on 13 December 2002 on the Solarpampa fault, a large EW-striking normal fault located about 25 km northwest of Sabancaya volcano. All of the deformation episodes between 2002 and 2013 are spatially distinct from the inflation seen near Sabancaya from 1992 to 1997. In addition to the activity at Sabancaya, we also observe deformation near Coropuna volcano, in the Andagua Valley, and in the region between Ticsani and Tutupaca volcanoes. InSAR images reveal surface deformation that is possibly related to an earthquake swarm near Coropuna and Sabancaya volcanoes in December 2001. We also find persistent deformation in the scoria cone and lava field along the Andagua Valley, located 40 km east of Corpuna. An earthquake swarm near Ticsani volcano in 2005 produced surface deformation centered northwest of the volcano and was accompanied by a north-south elongated subsidence signal to the

  10. Special Issue "Impact of Natural Hazards on Urban Areas and Infrastructure" in the Bulletin of Earthquake Engineering

    Science.gov (United States)

    Bostenaru Dan, M.

    2009-04-01

    This special issue includes selected papers on the topic of earthquake impact from the sessions held in 2004 in Nice, France and in 2005 in Vienna, Austria at the first and respectivelly the second European Geosciences Union General Assembly. Since its start in 1999, in the Hague, Netherlands, the hazard of earthquakes has been the most popular of the session. The respective calls in 2004 was for: Nature's forces including earthquakes, floods, landslides, high winds and volcanic eruptions can inflict losses to urban settlements and man-made structures such as infrastructure. In Europe, recent years have seen such significant losses from earthquakes in south and south-eastern Europe, floods in central Europe, and wind storms in western Europe. Meanwhile, significant progress has been made in understanding disasters. Several scientific fields contribute to a holistic approach in the evaluation of capacities, vulnerabilities and hazards, the main factors on mitigating urban disasters due to natural hazards. An important part of the session is devoted to assessment of earthquake shaking and loss scenarios, including both physical damage and human causalities. Early warning and rapid damage evaluation are of utmost importance for addressing the safety of many essential facilities, for emergency management of events and for disaster response. In case of earthquake occurrence strong motion networks, data processing and interpretation lead to preliminary estimation (scenarios) of geographical distribution of damages. Factual information on inflicted damage, like those obtained from shaking maps or aerial imagery permit a confrontation with simulation maps of damage in order to define a more accurate picture of the overall losses. Most recent developments towards quantitative and qualitative simulation of natural hazard impacts on urban areas, which provide decision-making support for urban disaster management, and success stories of and lessons learned from disaster

  11. Integrated Application of Remote Sensing, GIS and Hydrological Modeling to Estimate the Potential Impact Area of Earthquake-Induced Dammed Lakes

    OpenAIRE

    Bo Cao; Shengmei Yang; Song Ye

    2017-01-01

    Dammed lakes are an important secondary hazard caused by earthquakes. They can induce further damage to nearby humans. Current hydrology calculation research on dammed lakes usually lacks spatial expressive ability and cannot accurately conduct impact assessment without the support of remote sensing, which obtains important characteristic information of dammed lakes. The current study aims to address the issues of the potential impact area estimate of earthquake-induced dammed lakes by combin...

  12. Earthquake and human impact on the sedimentology and geochemistry of Ahuriri Estuary, Hawke's Bay

    International Nuclear Information System (INIS)

    Chague-Goff, C.; Nichol, S.L.; Ditchburn, R.G.; Trompetter, W.J.; Sutherland, V.T.

    1998-01-01

    Three cores were collected from the intertidal and salt marsh sediments in Ahuriri Estuary, Hawke's Bay, and analysed by sedimentological, chemical and geochronological techniques. Signatures of various events, of both natural and anthropogenic origin, were identified. Evidence for the 1931 Hawke's Bay earthquake, which resulted in an uplift of one to two metres in the Napier area, is given by a change in grainsize distribution in a core from the southern shore of the Lower Estuary. The change to a high energy environment, similar to the present one in the Lower Estuary, has resulted in deposition of sand over fine silt. The data suggest increased sediment accumulation rates following the uplift event, which might be attributed to increased erosion in the upper catchment. There is no evidence of the earthquake at the two other sites sampled, which is probably due to their more sheltered location in the estuary. Post-European settlement impact is mainly restricted to the Lower Estuary, where increased concentrations of Zn, Cr, Pb and Cu may be due to industrial discharges. Evidence of agricultural runoff is given by an increase in Cu concentrations near the Poraiti Hills. The chemical data (Cl and S) suggest a change in the depositional environment in the Upper Estuary due to increased freshwater influx and/or decrease in seawater influence. Dating by 210 Pb infers that this occurred prior to 1931, but the origin and timing of the event are still to be determined. Sediment accumulation rates have averaged 2.5 mm/yr for the last 45 years in the Lower Estuary and 3.8 mm/yr for the last 70 years or so in the Upper Estuary. The variation probably reflects the difference in depositional environment, from a high energy environment dominated by tidal and wave action to a low energy environment with additional organic and fine sediment input from stream runoff. The various signatures identified are based on known events but may be used for identifying events in other less

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

    Science.gov (United States)

    Muhammad, Ario; Goda, Katsuichiro

    2018-03-01

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

  14. Post-earthquake denudation and its impacts on ancient civilizations in the Chengdu Longmenshan region, China

    Science.gov (United States)

    Chen, Ningsheng; Li, Jun; Liu, Lihong; Yang, Chenglin; Liu, Mei

    2018-05-01

    This study characterizes significant changes in denudation and disasters in mountainous areas induced in the humid Chengdu Longmenshan region by the Wenchuan Earthquake in 2008. A study focusing on the Longxi-Baisha River Basin was conducted to investigate the amount of denudation triggered by specific flash flood and debris flow events in 2009-2014. The following results were obtained through a comparison of pre-seismic regional denudation rates and denudation characteristics of other seismically active mountain regions. (1) Regional denudation processes occurred in a wave-like process of initial increase then decline, with a peak exhibiting a hyperbolic attenuation trend. This trend indicates that the denudation rate in the Chengdu Longmenshan region is expected to return to the pre-seismic rate of 0.3 mm a-1 after 81 years. In 22 years after the earthquake (Year 2030), debris flow disasters are expected to be rare. (2) Disasters increased significantly in the Chengdu Longmenshan region after the Wenchuan earthquake, with an average of 29.5 people missing or dead per year (22 times greater than the pre-earthquake rate) and average economic losses of 192 million Yuan per year (1.6 times greater than the pre-earthquake rate). (3) The denudation process was jointly controlled by the quantities of loose solid material and precipitation after the Wenchuan earthquake. The amount of loose solid material influenced the extent of denudation, while vegetation coverage rates and soil consolidation determined the overall denudation trend in the region, and changes in precipitation led to denudation fluctuations. (4) The results can be used to analyze the relationship between the potential flash flood-debris flow disasters after earthquakes in the ancient Shu kingdom and changes in historical social settlements. The results can also be used to predict denudation processes and disaster risks from earthquakes in humid mountainous regions around the world, such as the southern

  15. Nurse Perspectives on the Practical, Emotional, and Professional Impacts of Living and Working in Post-earthquake Canterbury, New Zealand.

    Science.gov (United States)

    Johal, Sarbjit S; Mounsey, Zoe; Brannelly, Petula; Johnston, David M

    2016-02-01

    This report explores nurses' perspectives following the Canterbury (New Zealand) 2010-2011 earthquake sequence and the subsequent recovery process. Problem Little is known about the experiences of health care professionals during a disaster recovery process, and this research generates insights about the challenges faced. Qualitative semi-structured interviews were undertaken with 11 nurses from the Christchurch (New Zealand) area to explore the challenges faced by the nurses during and following the earthquakes. The interviews took place three years after the start of the earthquake experience to enable exploration of longer term aspects of the recovery process. The interview transcripts were analyzed and coded using a grounded theory approach. The data analysis identified that the nurses had faced a number of challenges and these were characterized as practical, emotional, and professional. While some of the challenges were short-lived in the aftermath of the earthquakes, some were long-lasting due to the extended nature of the recovery process. Dealing with house damage, insurance negotiations, and working in damaged environments had a negative impact on the nurses. The nurses experienced a range of emotions, both negative and positive, after the disaster, though many had needed time to elapse before feeling able to reflect on their experiences. The findings suggest that secondary stressors have a negative impact on the psychosocial recovery process. The nurses recognized that they received support from others and were also required to focus on others. Keeping busy appeared to be the most common coping strategy. This lack of reflection on their experiences may have resulted in delayed emotional responses. Some of the nurses changed their work role, hours, and responsibilities suggesting that working in this environment was having a detrimental impact. The research indicates the challenges faced by nurses in the initial impact of the earthquakes and during the

  16. Impacts of hydrogeological characteristics on groundwater-level changes induced by earthquakes

    Science.gov (United States)

    Liu, Ching-Yi; Chia, Yeeping; Chuang, Po-Yu; Chiu, Yung-Chia; Tseng, Tai-Lin

    2018-03-01

    Changes in groundwater level during earthquakes have been reported worldwide. In this study, field observations of co-seismic groundwater-level changes in wells under different aquifer conditions and sampling intervals due to near-field earthquake events in Taiwan are presented. Sustained changes, usually observed immediately after earthquakes, are found in the confined aquifer. Oscillatory changes due to the dynamic strain triggered by passing earthquake waves can only be recorded by a high-frequency data logger. While co-seismic changes recover rapidly in an unconfined aquifer, they can sustain for months or longer in a confined aquifer. Three monitoring wells with long-term groundwater-level data were examined to understand the association of co-seismic changes with local hydrogeological conditions. The finite element software ABAQUS is used to simulate the pore-pressure changes induced by the displacements due to fault rupture. The calculated co-seismic change in pore pressure is related to the compressibility of the formation. The recovery rate of the change is rapid in the unconfined aquifer due to the hydrostatic condition at the water table, but slow in the confined aquifer due to the less permeable confining layer. Fracturing of the confining layer during earthquakes may enhance the dissipation of pore pressure and induce the discharge of the confined aquifer. The study results indicated that aquifer characteristics play an important role in determining groundwater-level changes during and after earthquakes.

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

    Science.gov (United States)

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

    2017-12-01

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

  18. Relative chronology of Martian volcanoes

    International Nuclear Information System (INIS)

    Landheim, R.; Barlow, N.G.

    1991-01-01

    Impact cratering is one of the major geological processes that has affected the Martian surface throughout the planet's history. The frequency of craters within particular size ranges provides information about the formation ages and obliterative episodes of Martian geologic units. The Barlow chronology was extended by measuring small craters on the volcanoes and a number of standard terrain units. Inclusions of smaller craters in units previously analyzed by Barlow allowed for a more direct comparison between the size-frequency distribution data for volcanoes and established chronology. During this study, 11,486 craters were mapped and identified in the 1.5 to 8 km diameter range in selected regions of Mars. The results are summarized in this three page report and give a more precise estimate of the relative chronology of the Martian volcanoes. Also, the results of this study lend further support to the increasing evidence that volcanism has been a dominant geologic force throughout Martian history

  19. Establishment, test and evaluation of a prototype volcano surveillance system

    Science.gov (United States)

    Ward, P. L.; Eaton, J. P.; Endo, E.; Harlow, D.; Marquez, D.; Allen, R.

    1973-01-01

    A volcano-surveillance system utilizing 23 multilevel earthquake counters and 6 biaxial borehole tiltmeters is being installed and tested on 15 volcanoes in 4 States and 4 foreign countries. The purpose of this system is to give early warning when apparently dormant volcanoes are becoming active. The data are relayed through the ERTS-Data Collection System to Menlo Park for analysis. Installation was completed in 1972 on the volcanoes St. Augustine and Iliamna in Alaska, Kilauea in Hawaii, Baker, Rainier and St. Helens in Washington, Lassen in California, and at a site near Reykjavik, Iceland. Installation continues and should be completed in April 1973 on the volcanoes Santiaguito, Fuego, Agua and Pacaya in Guatemala, Izalco in El Salvador and San Cristobal, Telica and Cerro Negro in Nicaragua.

  20. Identification and impacts of earthquakes on the Roman Town of Patras- Archaeological evidence

    Science.gov (United States)

    Stamati, Alexandra-Venetia; Stiros, Stathis

    2015-04-01

    In this paper we examine the interactions between earthquakes and inhabitation history of the town of Patras (NW Peloponnese, Greece), flourishing during the Roman period. Instrumental seismicity data and the seismic history of the last two centuries indicate that the wider area is among the most seismically active parts of Europe. But surprisingly, for older periods no historical evidence of ancient earthquakes exists. If this absence of evidence of ancient earthquakes is indicative of a real absence of earthquakes, this may be important for different disciplines. For Seismology, it may perhaps indicate clusters of seismicity separated by intervals of quiescence, each at least several thousand years long. It may also indicate that the inhabitation history of Patras town was not interrupted by major natural catastrophic events, and some destruction observed in ancient remains can be assigned to anthropogenic effects. In order to contribute in the solution of this problem, we made a systematic Archaeoseismological investigation of Patras and examined for the first time several hundreds of reports of archaeological excavations that have been made during period of reconstruction of the city (1972-2004). Among these, about 100 reports provide evidence of destruction layers, some of which satisfy the criteria for identification of earthquakes from archaeological data. A further correlation of this evidence in space and time was made, and permitted to identify with certainty a few major seismic events which marked the history of Roman Patras (1st-6th century AD). In spite of their catastrophic effects, these earthquakes have not led to the abandonment of the ancient town (inhabitation hiatus), but have certainly left their marks in the urban and perhaps social and economic history of this Roman town. Some certain uniformity in the frequency of earthquakes in Patras was also inferred.

  1. Introduction - The impacts of the 2008 eruption of Kasatochi Volcano on terrestrial and marine ecosystems in the Aleutian Islands, Alaska

    Science.gov (United States)

    DeGange, Anthony R.; Byrd, G. Vernon; Walker, Lawrence R.; Waythomas, C.F.

    2010-01-01

    The Aleutian Islands are situated on the northern edge of the so-called “Pacific Ring of Fire,” a 40,000-km-long horseshoe-shaped assemblage of continental landmasses and islands bordering the Pacific Ocean basin that contains many of the world's active and dormant volcanoes. Schaefer et al. (2009) listed 27 historically active volcanoes in the Aleutian Islands, of which nine have had at least one major eruptive event since 1990. Volcanic eruptions are often significant natural disturbances, and ecosystem responses to volcanic eruptions may vary markedly with eruption style (effusive versus explosive), frequency, and magnitude of the eruption as well as isolation of the disturbed sites from potential colonizing organisms (del Moral and Grishin, 1999). Despite the relatively high frequency of volcanic activity in the Aleutians, the response of island ecosystems to volcanic disturbances is largely unstudied because of the region's isolation. The only ecological studies in the region that address the effects of volcanic activity were done on Bogoslof Island, a remote, highly active volcanic island in the eastern Aleutians, which grew from a submarine eruption in 1796 (Merriam, 1910; Byrd et al., 1980; Byrd and Williams, 1994). Nevertheless, in the 214 years of Bogoslof's existence, the island has been visited only intermittently.Kasatochi Island is a small (2.9 km by 2.6 km, 314 m high) volcano in the central Aleutian Islands of Alaska (52.17°N latitude, 175.51°W longitude; Fig. 1) that erupted violently on 7-8 August 2008 after a brief, but intense period of precursory seismic activity (Scott et al., 2010 [this issue]; Waythomas et al., in review). The island is part of the Aleutian arc volcanic front, and is an isolated singular island. Although the immediate offshore areas are relatively shallow (20–50 m water depth), the island is about 10 km south of the 2000 m isobath, north of which, ocean depths increase markedly. Kasatochi is located between the

  2. The Challenge of Centennial Earthquakes to Improve Modern Earthquake Engineering

    International Nuclear Information System (INIS)

    Saragoni, G. Rodolfo

    2008-01-01

    The recent commemoration of the centennial of the San Francisco and Valparaiso 1906 earthquakes has given the opportunity to reanalyze their damages from modern earthquake engineering perspective. These two earthquakes plus Messina Reggio Calabria 1908 had a strong impact in the birth and developing of earthquake engineering. The study of the seismic performance of some up today existing buildings, that survive centennial earthquakes, represent a challenge to better understand the limitations of our in use earthquake design methods. Only Valparaiso 1906 earthquake, of the three considered centennial earthquakes, has been repeated again as the Central Chile, 1985, Ms = 7.8 earthquake. In this paper a comparative study of the damage produced by 1906 and 1985 Valparaiso earthquakes is done in the neighborhood of Valparaiso harbor. In this study the only three centennial buildings of 3 stories that survived both earthquakes almost undamaged were identified. Since for 1985 earthquake accelerogram at El Almendral soil conditions as well as in rock were recoded, the vulnerability analysis of these building is done considering instrumental measurements of the demand. The study concludes that good performance of these buildings in the epicentral zone of large earthquakes can not be well explained by modern earthquake engineering methods. Therefore, it is recommended to use in the future of more suitable instrumental parameters, such as the destructiveness potential factor, to describe earthquake demand

  3. Latur earthquake and its impact on the aseismic design of structures in India

    International Nuclear Information System (INIS)

    Basu, P.C.

    1995-01-01

    The Latur earthquake occurred on September 30, 1995. The epicentre was located near the Killari village of Latur District which is situated in the stable continental region of Southern Peninsular India. The earthquake caused a wide range of damage though its magnitude (MS) was 6.4. Intensive damage survey was carried out and a number of geophysical and seismological studies had been undertaken. It has been concluded from the results, available so far from these studies, that the hypocentre of the earthquake was on the lineament dipping NW-SE. The rock matrix in the hypocentral region was weakened due to the presence of fluid and rupture of this weak region caused the event. The ground motion produced by the earthquake was of complex nature comprising of horizontal and vertical component. The ground acceleration in the epicentral region was estimated as 0.2 g. Latur earthquake raised several issues with respect to aseismic design of structures in India which need further deliberation. These issues are related to seismic zoning of India, determination of design basis ground motion, design/detailing of structures, etc. (author)

  4. Latur earthquake and its impact on the aseismic design of structures in India

    Energy Technology Data Exchange (ETDEWEB)

    Basu, P C [Atomic Energy Regulatory Board (India)

    1995-07-01

    The Latur earthquake occurred on September 30, 1995. The epicentre was located near the Killari village of Latur District which is situated in the stable continental region of Southern Peninsular India. The earthquake caused a wide range of damage though its magnitude (MS) was 6.4. Intensive damage survey was carried out and a number of geophysical and seismological studies had been undertaken. It has been concluded from the results, available so far from these studies, that the hypocentre of the earthquake was on the lineament dipping NW-SE. The rock matrix in the hypocentral region was weakened due to the presence of fluid and rupture of this weak region caused the event. The ground motion produced by the earthquake was of complex nature comprising of horizontal and vertical component. The ground acceleration in the epicentral region was estimated as 0.2 g. Latur earthquake raised several issues with respect to aseismic design of structures in India which need further deliberation. These issues are related to seismic zoning of India, determination of design basis ground motion, design/detailing of structures, etc. (author)

  5. Global Volcano Locations Database

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NGDC maintains a database of over 1,500 volcano locations obtained from the Smithsonian Institution Global Volcanism Program, Volcanoes of the World publication. The...

  6. A Scientific Excursion: Volcanoes.

    Science.gov (United States)

    Olds, Henry, Jr.

    1983-01-01

    Reviews an educationally valuable and reasonably well-designed simulation of volcanic activity in an imaginary land. VOLCANOES creates an excellent context for learning information about volcanoes and for developing skills and practicing methods needed to study behavior of volcanoes. (Author/JN)

  7. Sequential population study of the impact of earthquakes on the emotional and behavioural well-being of 4-year-olds in Canterbury, New Zealand.

    Science.gov (United States)

    Thomson, Janine; Seers, Kara; Frampton, Chris; Hider, Phil; Moor, Stephanie

    2016-01-01

    Exposure to a large natural disaster can lead to behavioural disturbances, developmental delay and anxiety among young children. Although most children are resilient, some will develop mental health problems. Major earthquakes occurred in Canterbury, New Zealand, in September 2010 and February 2011. A community screening tool assessing behavioural and emotional problems in children, the Strengths and Difficulties Questionnaire, has been reported by parents (SDQ-P) and teachers (SDQ-T) of all 4-year-olds in the region since 2008. Mean total and subtest scores for the SDQ-P and SDQ-T were compared across periods before, during and after the earthquakes in sequential population cohorts of children. Comparisons across the periods were made in relation to the proportions of children defined by New Zealand norms as 'abnormal'. Results were also compared between zones considered to have been exposed to higher or lower impact from the earthquakes. Parent mean total SDQ scores did not change between periods before, during and after the earthquakes. Teacher mean SDQ total scores significantly reduced (improved) when compared between baseline and post-earthquake periods. Mean SDQ pro-social scores from both teachers and parents increased (strengthened) when compared between baseline and post-earthquake periods. Results did not significantly vary according to a measure of impact from the earthquakes. The main finding that a population-based measure of behavioural and emotional problems among children was not deleteriously impacted by the earthquakes is surprising and is not consistent with other research findings. Further work is needed to explore the health needs of children in Canterbury based on methodological improvements. © 2015 The Authors. Journal of Paediatrics and Child Health © 2015 Paediatrics and Child Health Division (Royal Australasian College of Physicians).

  8. Spatial analysis of the impacts of the Chaitén volcano eruption (Chile) in three fluvial systems

    Science.gov (United States)

    Ulloa, H.; Iroumé, A.; Picco, L.; Mohr, C. H.; Mazzorana, B.; Lenzi, M. A.; Mao, L.

    2016-08-01

    The eruption of the Chaitén volcano in May 2008 generated morphological and ecological disturbances in adjacent river basins, and the magnitude of these disturbances depended on the type of dominant volcanic process affecting each of them. The aim of this study is to analyse the morphological changes in different periods in river segments of the Blanco, El Amarillo and Rayas river basins located near the Chaitén volcano. These basins suffered disturbances of different intensity and spatial distribution caused by tephra fall, dome collapses and pyroclastic density currents that damaged hillslope forests, widened channels and destroyed island and floodplain vegetation. Changes continued to occur in the fluvial systems in the years following the eruption, as a consequence of the geomorphic processes indirectly induced by the eruption. Channel changes were analyzed by comparing remote images of pre and post-eruption conditions. Two periods were considered: the first from 2008 to 2009-2010 associated with the explosive and effusive phases of the eruption and the second that correspond to the post-eruption stage from 2009-2010 to 2013. Following the first phases channel segments widened 91% (38 m/yr), 6% (7 m/yr) and 7% (22 m/yr) for Blanco, Rayas and El Amarillo Rivers, respectively, compared to pre-eruption condition. In the second period, channel segments additionally widened 42% (8 m/yr), 2% (2 m/yr) and 5% (4 m/yr) for Blanco, Rayas and El Amarillo Rivers, respectively. In the Blanco River 62 and 82% of the islands disappeared in the first and second period, respectively, which is 6-8 times higher than in the El Amarillo approximately twice the Rayas. Sinuosity increased after the eruption only in the Blanco River but the three study channels showed a high braiding intensity mainly during the first post-eruption period. The major disturbances occurred during the eruptive and effusive phases of Chaitén volcano, and the intensity of these disturbances reflects the

  9. The Academic Impact of Natural Disasters: Evidence from L'Aquila Earthquake

    Science.gov (United States)

    Di Pietro, Giorgio

    2018-01-01

    This paper uses a standard difference-in-differences approach to examine the effect of the L'Aquila earthquake on the academic performance of the students of the local university. The empirical results indicate that this natural disaster reduced students' probability of graduating on-time and slightly increased students' probability of dropping…

  10. On the Distribution of Earthquake Interevent Times and the Impact of Spatial Scale

    Science.gov (United States)

    Hristopulos, Dionissios

    2013-04-01

    The distribution of earthquake interevent times is a subject that has attracted much attention in the statistical physics literature [1-3]. A recent paper proposes that the distribution of earthquake interevent times follows from the the interplay of the crustal strength distribution and the loading function (stress versus time) of the Earth's crust locally [4]. It was also shown that the Weibull distribution describes earthquake interevent times provided that the crustal strength also follows the Weibull distribution and that the loading function follows a power-law during the loading cycle. I will discuss the implications of this work and will present supporting evidence based on the analysis of data from seismic catalogs. I will also discuss the theoretical evidence in support of the Weibull distribution based on models of statistical physics [5]. Since other-than-Weibull interevent times distributions are not excluded in [4], I will illustrate the use of the Kolmogorov-Smirnov test in order to determine which probability distributions are not rejected by the data. Finally, we propose a modification of the Weibull distribution if the size of the system under investigation (i.e., the area over which the earthquake activity occurs) is finite with respect to a critical link size. keywords: hypothesis testing, modified Weibull, hazard rate, finite size References [1] Corral, A., 2004. Long-term clustering, scaling, and universality in the temporal occurrence of earthquakes, Phys. Rev. Lett., 9210) art. no. 108501. [2] Saichev, A., Sornette, D. 2007. Theory of earthquake recurrence times, J. Geophys. Res., Ser. B 112, B04313/1-26. [3] Touati, S., Naylor, M., Main, I.G., 2009. Origin and nonuniversality of the earthquake interevent time distribution Phys. Rev. Lett., 102 (16), art. no. 168501. [4] Hristopulos, D.T., 2003. Spartan Gibbs random field models for geostatistical applications, SIAM Jour. Sci. Comput., 24, 2125-2162. [5] I. Eliazar and J. Klafter, 2006

  11. Pb isotope composition in lichens and aerosols from eastern Sicily: Insights into the regional impact of volcanoes on the environment

    Energy Technology Data Exchange (ETDEWEB)

    Monna, F. (Institut FA Forel (Switzerland)); Aiuppa, A.; Varrica, D. (Dipt. C.F.T.A., Palermo (Italy)); Dongarra, G. (Dipt. C.F.T.A., Palermo (Italy) CNR, Palermo (Italy). Istituto Geochimica dei Fluidi)

    1999-08-01

    A total of 25 lichen thalli of Parmelia conspersa (Ehrh), collected at Vulcano island and at Mt. Etna, during a one-year biogeochemical survey, were analyzed for Pb, br, Al, Sc,[sup 206]Pb/[sup 207]Pb, and [sup 208]Pb/[sup 206]Pb ratios. Lead isotope ratios were also measured on aerosol samples from urban areas and industrial sites of Sicily. The observed [sup 206]Pb/[sup 207]Pb range for urban and industrial aerosols matches the anthropogenic signature. Lichens instead, are closer to the compositional field of [sup 206]Pb rich geogenic sources. This natural input is more evident at Vulcano island than at Mt. Etna, where the anthropogenic activities are considerably more effective. On the basis of lead isotope data, Pb/Br ratios and calculated lead enrichment factors, a natural lead pollution from volcanoes is suggested. Volcanic lead contribution ranges from 10 to 30% at Mt. Etna to 10--80% at Vulcano island.

  12. Alaska volcanoes guidebook for teachers

    Science.gov (United States)

    Adleman, Jennifer N.

    2011-01-01

    Alaska’s volcanoes, like its abundant glaciers, charismatic wildlife, and wild expanses inspire and ignite scientific curiosity and generate an ever-growing source of questions for students in Alaska and throughout the world. Alaska is home to more than 140 volcanoes, which have been active over the last 2 million years. About 90 of these volcanoes have been active within the last 10,000 years and more than 50 of these have been active since about 1700. The volcanoes in Alaska make up well over three-quarters of volcanoes in the United States that have erupted in the last 200 years. In fact, Alaska’s volcanoes erupt so frequently that it is almost guaranteed that an Alaskan will experience a volcanic eruption in his or her lifetime, and it is likely they will experience more than one. It is hard to imagine a better place for students to explore active volcanism and to understand volcanic hazards, phenomena, and global impacts. Previously developed teachers’ guidebooks with an emphasis on the volcanoes in Hawaii Volcanoes National Park (Mattox, 1994) and Mount Rainier National Park in the Cascade Range (Driedger and others, 2005) provide place-based resources and activities for use in other volcanic regions in the United States. Along the lines of this tradition, this guidebook serves to provide locally relevant and useful resources and activities for the exploration of numerous and truly unique volcanic landscapes in Alaska. This guidebook provides supplemental teaching materials to be used by Alaskan students who will be inspired to become educated and prepared for inevitable future volcanic activity in Alaska. The lessons and activities in this guidebook are meant to supplement and enhance existing science content already being taught in grade levels 6–12. Correlations with Alaska State Science Standards and Grade Level Expectations adopted by the Alaska State Department of Education and Early Development (2006) for grades six through eleven are listed at

  13. Remote Triggering of Microearthquakes in the Piton de la Fournaise and Changbaishan Volcanoes

    Science.gov (United States)

    Li, C.; Liu, G.; Peng, Z.; Brenguier, F.; Dufek, J.

    2015-12-01

    Large earthquakes are capable of triggering seismic, aseismic and hydrological responses at long-range distances. In particular, recent studies have shown that microearthquakes are mostly triggered in volcanic/geothermal regions. However, it is still not clear how widespread the phenomenon is, and whether there are any causal links between large earthquakes and subsequent volcanic unrest/eruptions. In this study we conduct a systematic search for remotely triggered activity at the Piton de la Fournaise (PdlF) and Changbaishan (CBS) volcanoes. The PdlF is a shield volcano located on the east-southern part of the Reunion Island in Indian Ocean. It is one of the most active volcanoes around the world. The CBS volcano is an intraplate stratovolcano on the border between China and North Korea, and it was active with a major eruption around 1100 years ago and has been since dormant from AD 1903, however, it showed signals of unrest recently. We choose these regions because they are well instrumented and spatially close to recent large earthquakes, such as the 2004/12/26 Mw9.1 Sumatra, 2011/03/11 Mw9.0 Tohoku, and the 2012/04/11 Mw8.6 Indian Ocean Earthquakes. By examining continuous waveforms a few hours before and after many earthquakes since 2000, we find many cases of remote triggering around the CBS volcano. In comparison, we only identify a few cases of remotely triggered seismicity around the PdlF volcano, including the 2004 Sumatra earthquake. Notably, the 2012 Indian Ocean earthquake and its M8.2 aftershock did not trigger any clear increase of seismicity, at least during their surface waves. Our next step is to apply a waveform matching method to automatically detect volcano-seismicity in both regions, and then use them to better understand potential interactions between large earthquakes and volcanic activities.

  14. Providing Hands on Experiences to Museum Visitors to Explore and Learn about Earthquakes and their Impacts in the Pacific Northwest

    Science.gov (United States)

    Olds, S. E.; Schiffman, C. R.; Butler, R. F.; Farley, M.; Frankel, S.; Hunter, N.; Lillie, R. J.

    2013-12-01

    Over the past ten years, UNAVCO has developed a suite of learning materials for formal undergraduate and grades 6-12 classroom environments, integrating GPS data from the EarthScope Plate Boundary Observatory (PBO) to explore Earth science processes. To make complex Earth processes accessible to general audiences, UNAVCO has designed a multi-component visiting museum exhibit that explores the tectonic setting of the United States Pacific Northwest, hazards of living on a plate boundary, and the technologies being used to study the plate motion and in the future, help communities become more resilient to the impacts of earthquakes. This exhibit was installed in Fall 2013 at the Oregon State University (OSU) Hatfield Marine Science Center (HMSC) in Newport, Oregon. Through multiple hands-on elements, visitors to the HMSC exhibit explore and experience the build up and release of strain in the region, along with some of the technologies used to measure these changes. In one component, visitors compress a model of the Pacific Northwest to feel the build up of strain in the landscape and observe the movement of land over time. Supporting panels connect this movement to the measurements currently being observed by the network of PBO and other GPS stations in the Pacific Northwest. In another component, visitors learn about the recurrence interval for earthquakes at the Juan De Fuca - North America plate boundary by turning a handle to slowly move and compress plates until a simulated earthquake occurs. A related component explores how an earthquake early warning system (EEWS) of the future might combine seismic data collected by both seismometers and real time GPS to allow people and communities time to prepare for oncoming ground shaking and tsunami after an earthquake. Several technologies are also highlighted throughout the exhibit, including information panels that compare the accuracy of high precision GPS with smartphone technologies. Additionally, models of a full

  15. Catalog of Hawaiian earthquakes, 1823-1959

    Science.gov (United States)

    Klein, Fred W.; Wright, Thomas L.

    2000-01-01

    This catalog of more than 17,000 Hawaiian earthquakes (of magnitude greater than or equal to 5), principally located on the Island of Hawaii, from 1823 through the third quarter of 1959 is designed to expand our ability to evaluate seismic hazard in Hawaii, as well as our knowledge of Hawaiian seismic rhythms as they relate to eruption cycles at Kilauea and Mauna Loa volcanoes and to subcrustal earthquake patterns related to the tectonic evolution of the Hawaiian chain.

  16. Imaging magma plumbing beneath Askja volcano, Iceland

    Science.gov (United States)

    Greenfield, Tim; White, Robert S.

    2015-04-01

    Volcanoes during repose periods are not commonly monitored by dense instrumentation networks and so activity during periods of unrest is difficult to put in context. We have operated a dense seismic network of 3-component, broadband instruments around Askja, a large central volcano in the Northern Volcanic Zone, Iceland, since 2006. Askja last erupted in 1961, with a relatively small basaltic lava flow. Since 1975 the central caldera has been subsiding and there has been no indication of volcanic activity. Despite this, Askja has been one of the more seismically active volcanoes in Iceland. The majority of these events are due to an extensive geothermal area within the caldera and tectonically induced earthquakes to the northeast which are not related to the magma plumbing system. More intriguing are the less numerous deeper earthquakes at 12-24km depth, situated in three distinct areas within the volcanic system. These earthquakes often show a frequency content which is lower than the shallower activity, but they still show strong P and S wave arrivals indicative of brittle failure, despite their location being well below the brittle-ductile boundary, which, in Askja is ~7km bsl. These earthquakes indicate the presence of melt moving or degassing at depth while the volcano is not inflating, as only high strain rates or increased pore fluid pressures would cause brittle fracture in what is normally an aseismic region in the ductile zone. The lower frequency content must be the result of a slower source time function as earthquakes which are both high frequency and low frequency come from the same cluster, thereby discounting a highly attenuating lower crust. To image the plumbing system beneath Askja, local and regional earthquakes have been used as sources to solve for the velocity structure beneath the volcano. Travel-time tables were created using a finite difference technique and the residuals were used to solve simultaneously for both the earthquake locations

  17. High resolution measurement of earthquake impacts on rock slope stability and damage using pre- and post-earthquake terrestrial laser scans

    Science.gov (United States)

    Hutchinson, Lauren; Stead, Doug; Rosser, Nick

    2017-04-01

    Understanding the behaviour of rock slopes in response to earthquake shaking is instrumental in response and relief efforts following large earthquakes as well as to ongoing risk management in earthquake affected areas. Assessment of the effects of seismic shaking on rock slope kinematics requires detailed surveys of the pre- and post-earthquake condition of the slope; however, at present, there is a lack of high resolution monitoring data from pre- and post-earthquake to facilitate characterization of seismically induced slope damage and validate models used to back-analyze rock slope behaviour during and following earthquake shaking. Therefore, there is a need for additional research where pre- and post- earthquake monitoring data is available. This paper presents the results of a direct comparison between terrestrial laser scans (TLS) collected in 2014, the year prior to the 2015 earthquake sequence, with that collected 18 months after the earthquakes and two monsoon cycles. The two datasets were collected using Riegl VZ-1000 and VZ-4000 full waveform laser scanners with high resolution (c. 0.1 m point spacing as a minimum). The scans cover the full landslide affected slope from the toe to the crest. The slope is located in Sindhupalchok District, Central Nepal which experienced some of the highest co-seismic and post-seismic landslide intensities across Nepal due to the proximity to the epicenters (<20 km) of both of the main aftershocks on April 26, 2015 (M 6.7) and May 12, 2015 (M7.3). During the 2015 earthquakes and subsequent 2015 and 2016 monsoons, the slope experienced rockfall and debris flows which are evident in satellite imagery and field photographs. Fracturing of the rock mass associated with the seismic shaking is also evident at scales not accessible through satellite and field observations. The results of change detection between the TLS datasets with an emphasis on quantification of seismically-induced slope damage is presented. Patterns in the

  18. Earthquake Culture: A Significant Element in Earthquake Disaster Risk Assessment and Earthquake Disaster Risk Management

    OpenAIRE

    Ibrion, Mihaela

    2018-01-01

    This book chapter brings to attention the dramatic impact of large earthquake disasters on local communities and society and highlights the necessity of building and enhancing the earthquake culture. Iran was considered as a research case study and fifteen large earthquake disasters in Iran were investigated and analyzed over more than a century-time period. It was found that the earthquake culture in Iran was and is still conditioned by many factors or parameters which are not integrated and...

  19. The 2014 eruptions of Pavlof Volcano, Alaska

    Science.gov (United States)

    Waythomas, Christopher F.; Haney, Matthew M.; Wallace, Kristi; Cameron, Cheryl E.; Schneider, David J.

    2017-12-22

    across the region results in a relatively large number of airborne observations of eruptive activity. During the 2014 Pavlof eruptions, the Alaska Volcano Observatory received observations and photographs from pilots and local observers, which aided evaluation of the eruptive activity and the areas affected by eruptive products.This report outlines the chronology of events associated with the 2014 eruptive activity at Pavlof Volcano, provides documentation of the style and character of the eruptive episodes, and reports briefly on the eruptive products and impacts. The principal observations are described and portrayed on maps and photographs, and the 2014 eruptive activity is compared to historical eruptions.

  20. Protocols for geologic hazards response by the Yellowstone Volcano Observatory

    Science.gov (United States)

    ,

    2010-01-01

    The Yellowstone Plateau hosts an active volcanic system, with subterranean magma (molten rock), boiling, pressurized waters, and a variety of active faults with significant earthquake hazards. Within the next few decades, light-to-moderate earthquakes and steam explosions are certain to occur. Volcanic eruptions are less likely, but are ultimately inevitable in this active volcanic region. This document summarizes protocols, policies, and tools to be used by the Yellowstone Volcano Observatory (YVO) during earthquakes, hydrothermal explosions, or any geologic activity that could lead to a volcanic eruption.

  1. When probabilistic seismic hazard climbs volcanoes: the Mt. Etna case, Italy - Part 2: Computational implementation and first results

    Science.gov (United States)

    Peruzza, Laura; Azzaro, Raffaele; Gee, Robin; D'Amico, Salvatore; Langer, Horst; Lombardo, Giuseppe; Pace, Bruno; Pagani, Marco; Panzera, Francesco; Ordaz, Mario; Suarez, Miguel Leonardo; Tusa, Giuseppina

    2017-11-01

    This paper describes the model implementation and presents results of a probabilistic seismic hazard assessment (PSHA) for the Mt. Etna volcanic region in Sicily, Italy, considering local volcano-tectonic earthquakes. Working in a volcanic region presents new challenges not typically faced in standard PSHA, which are broadly due to the nature of the local volcano-tectonic earthquakes, the cone shape of the volcano and the attenuation properties of seismic waves in the volcanic region. These have been accounted for through the development of a seismic source model that integrates data from different disciplines (historical and instrumental earthquake datasets, tectonic data, etc.; presented in Part 1, by Azzaro et al., 2017) and through the development and software implementation of original tools for the computation, such as a new ground-motion prediction equation and magnitude-scaling relationship specifically derived for this volcanic area, and the capability to account for the surficial topography in the hazard calculation, which influences source-to-site distances. Hazard calculations have been carried out after updating the most recent releases of two widely used PSHA software packages (CRISIS, as in Ordaz et al., 2013; the OpenQuake engine, as in Pagani et al., 2014). Results are computed for short- to mid-term exposure times (10 % probability of exceedance in 5 and 30 years, Poisson and time dependent) and spectral amplitudes of engineering interest. A preliminary exploration of the impact of site-specific response is also presented for the densely inhabited Etna's eastern flank, and the change in expected ground motion is finally commented on. These results do not account for M > 6 regional seismogenic sources which control the hazard at long return periods. However, by focusing on the impact of M risk reduction.

  2. Volcanoes: Nature's Caldrons Challenge Geochemists.

    Science.gov (United States)

    Zurer, Pamela S.

    1984-01-01

    Reviews various topics and research studies on the geology of volcanoes. Areas examined include volcanoes and weather, plate margins, origins of magma, magma evolution, United States Geological Survey (USGS) volcano hazards program, USGS volcano observatories, volcanic gases, potassium-argon dating activities, and volcano monitoring strategies.…

  3. Impact of 2015 earthquakes on a local hospital in Nepal: A prospective hospital-based study.

    Science.gov (United States)

    Giri, Samita; Risnes, Kari; Uleberg, Oddvar; Rogne, Tormod; Shrestha, Sanu Krishna; Nygaard, Øystein Petter; Koju, Rajendra; Solligård, Erik

    2018-01-01

    Natural disasters pose a great challenge to the health systems and individual health facilities. In low-resource settings, disaster preparedness systems are often limited and not been well described. Two devastating earthquakes hit Nepal within a 17-days period in 2015. This study aims to describe the burden and distribution of emergency cases to a local hospital. This is a prospective observational study of patients presenting to a local hospital for a period of 21 days following the earthquake on April 25, 2015. Demographic and clinical information was prospectively registered for all patients in the systematic emergency registry. Systematic telephone interviews were conducted in a random sample of the patients 90 days after admission to the hospital. A total of 2,003 emergency patients were registered during the period. The average daily number of emergency patients during the first five days was almost five times higher (n = 150) than the pre-incident daily average (n = 35). The majority of injuries were fractures (58%), 348 (56%) in the lower extremities. A total of 345 surgical procedures were performed and the hospital treated 111 patients with severe injuries related to the earthquake (compartment syndrome, crush injury, and internal injury). Among those with follow-up interviews, over 90% reported that they had been severely affected by the earthquakes; complete house damage, living in temporary shelter, or loss of close family member. The hospital experienced a very high caseload during the first days, and the majority of patients needed orthopaedic services. The proportion of severely injured and in-hospital deaths were relatively low, probably indicating that the most severely injured did not reach the hospital in time. The experiences underline the need for robust and easily available local health services that can respond to disasters.

  4. Defeating Earthquakes

    Science.gov (United States)

    Stein, R. S.

    2012-12-01

    The 2004 M=9.2 Sumatra earthquake claimed what seemed an unfathomable 228,000 lives, although because of its size, we could at least assure ourselves that it was an extremely rare event. But in the short space of 8 years, the Sumatra quake no longer looks like an anomaly, and it is no longer even the worst disaster of the Century: 80,000 deaths in the 2005 M=7.6 Pakistan quake; 88,000 deaths in the 2008 M=7.9 Wenchuan, China quake; 316,000 deaths in the M=7.0 Haiti, quake. In each case, poor design and construction were unable to withstand the ferocity of the shaken earth. And this was compounded by inadequate rescue, medical care, and shelter. How could the toll continue to mount despite the advances in our understanding of quake risk? The world's population is flowing into megacities, and many of these migration magnets lie astride the plate boundaries. Caught between these opposing demographic and seismic forces are 50 cities of at least 3 million people threatened by large earthquakes, the targets of chance. What we know for certain is that no one will take protective measures unless they are convinced they are at risk. Furnishing that knowledge is the animating principle of the Global Earthquake Model, launched in 2009. At the very least, everyone should be able to learn what his or her risk is. At the very least, our community owes the world an estimate of that risk. So, first and foremost, GEM seeks to raise quake risk awareness. We have no illusions that maps or models raise awareness; instead, earthquakes do. But when a quake strikes, people need a credible place to go to answer the question, how vulnerable am I, and what can I do about it? The Global Earthquake Model is being built with GEM's new open source engine, OpenQuake. GEM is also assembling the global data sets without which we will never improve our understanding of where, how large, and how frequently earthquakes will strike, what impacts they will have, and how those impacts can be lessened by

  5. One hundred years of volcano monitoring in Hawaii

    Science.gov (United States)

    Kauahikaua, Jim; Poland, Mike

    2012-01-01

    In 2012 the Hawaiian Volcano Observatory (HVO), the oldest of five volcano observatories in the United States, is commemorating the 100th anniversary of its founding. HVO's location, on the rim of Kilauea volcano (Figure 1)—one of the most active volcanoes on Earth—has provided an unprecedented opportunity over the past century to study processes associated with active volcanism and develop methods for hazards assessment and mitigation. The scientifically and societally important results that have come from 100 years of HVO's existence are the realization of one man's vision of the best way to protect humanity from natural disasters. That vision was a response to an unusually destructive decade that began the twentieth century, a decade that saw almost 200,000 people killed by the effects of earthquakes and volcanic eruptions.

  6. Impact of the May 12, 2008, Earthquake on blood donations across five Chinese blood centers.

    Science.gov (United States)

    Liu, Jing; Huang, Yi; Wang, Jingxing; Bi, Xinhong; Li, Julin; Lu, Yunlai; Wen, Xiuqiong; Yao, Fuzhu; Dong, Xiangdong; He, Weilan; Huang, Mei; Ma, Hongli; Mei, Heili; King, Melissa; Wright, David J; Ness, Paul M; Shan, Hua

    2010-09-01

    On May 12, 2008, a severe earthquake struck China's Sichuan Province. The nationwide outpouring of charity resulted in a surge of subsequent blood donations. The quantity and quality of these donations were examined in comparison with routine donations. Whole blood and apheresis donations from five geographically different blood centers collected within 1 week postearthquake were compared with those collected during the rest of the year. Regional differences, demographic characteristics, first-time and repeat donor status, and infectious disease screening markers associated with these donations were compared by earthquake status using chi-square statistics. Poisson regression analysis examined the number of daily donations by earthquake status after adjusting for center, day of week, and seasonal variations. The number of daily donations across five blood centers increased from 685 on a typical day to 1151 in the postearthquake week. The surge was observed in both sexes and across different education levels, age, and ethnicity groups and three blood centers and was significant after adjusting for confounding covariates. The influx of first-time donors (89.5%) was higher than that of repeat donors (34%). There was a significant change in the overall screening reactive marker rates excluding alanine aminotransferase (2.06% vs. 1.72%% vs. 4.96%). However, when the individual screening test was analyzed separately, no significant differences were found. Timely donations in response to a disaster are crucial to ensure emergency blood transfusion. The dramatically increased postearthquake donations suggest that Chinese blood centers are capable of handling emergency blood needs. Measures to maintain blood safety should be taken in times of emergency. © 2010 American Association of Blood Banks.

  7. Urban Security Initiative: Earthquake impacts on the urban ``system of systems``

    Energy Technology Data Exchange (ETDEWEB)

    Maheshwari, S.; Jones, E.; Rasmussen, S.

    1999-06-01

    This paper is a discussion of how to address the problems of disasters in a large city, a project titled Urban Security Initiative undertaken by the Los Alamos National Laboratory. The paper first discusses the need to address the problems of disasters in large cities and ten provides a framework that is suitable to address this problem. The paper then provides an overview of the module of the project that deals with assessment of earthquake damage on urban infrastructure in large cities and an internet-based approach for consensus building leading to better coordination in the post-disaster period. Finally, the paper discusses the future direction of the project.

  8. Earthquake prediction

    International Nuclear Information System (INIS)

    Ward, P.L.

    1978-01-01

    The state of the art of earthquake prediction is summarized, the possible responses to such prediction are examined, and some needs in the present prediction program and in research related to use of this new technology are reviewed. Three basic aspects of earthquake prediction are discussed: location of the areas where large earthquakes are most likely to occur, observation within these areas of measurable changes (earthquake precursors) and determination of the area and time over which the earthquake will occur, and development of models of the earthquake source in order to interpret the precursors reliably. 6 figures

  9. Darwin's triggering mechanism of volcano eruptions

    Science.gov (United States)

    Galiev, Shamil

    2010-05-01

    Charles Darwin wrote that ‘… the elevation of many hundred square miles of territory near Concepcion is part of the same phenomenon, with that splashing up, if I may so call it, of volcanic matter through the orifices in the Cordillera at the moment of the shock;…' and ‘…a power, I may remark, which acts in paroxysmal upheavals like that of Concepcion, and in great volcanic eruptions,…'. Darwin reports that ‘…several of the great chimneys in the Cordillera of central Chile commenced a fresh period of activity ….' In particular, Darwin reported on four-simultaneous large eruptions from the following volcanoes: Robinson Crusoe, Minchinmavida, Cerro Yanteles and Peteroa (we cite the Darwin's sentences following his The Voyage of the Beagle and researchspace. auckland. ac. nz/handle/2292/4474). Let us consider these eruptions taking into account the volcano shape and the conduit. Three of the volcanoes (Minchinmavida (2404 m), Cerro Yanteles (2050 m), and Peteroa (3603 m)) are stratovolcanos and are formed of symmetrical cones with steep sides. Robinson Crusoe (922 m) is a shield volcano and is formed of a cone with gently sloping sides. They are not very active. We may surmise, that their vents had a sealing plug (vent fill) in 1835. All these volcanoes are conical. These common features are important for Darwin's triggering model, which is discussed below. The vent fill material, usually, has high level of porosity and a very low tensile strength and can easily be fragmented by tension waves. The action of a severe earthquake on the volcano base may be compared with a nuclear blast explosion of the base. It is known, that after a underground nuclear explosion the vertical motion and the surface fractures in a tope of mountains were observed. The same is related to the propagation of waves in conical elements. After the explosive load of the base. the tip may break and fly off at high velocity. Analogous phenomenon may be generated as a result of a

  10. Impacts of the 2011 Tohoku earthquake on electricity demand in Japan. State space approach

    International Nuclear Information System (INIS)

    Honjo, Keita; Ashina, Shuichi

    2017-01-01

    Some papers report that consumers' electricity saving behavior (Setsuden) after the 2011 Tohoku Earthquake resulted in the reduction of the domestic electricity demand. However, time variation of the electricity saving effect (ESE) has not yet been sufficiently investigated. In this study, we develop a state space model of monthly electricity demand using long-term data, and estimate time variation of the ESE. We also estimate time variation of CO_2 emissions caused by Setsuden. Our result clearly indicates that Setsuden after the earthquake was not temporary but became established as a habit. Between March 2011 and October 2015, the ESE on power demand ranged from 2.9% to 6.9%, and the ESE on light demand ranged from 2.6% to 9.0%. The ESE on the total electricity demand was 3.2%-7.5%. Setsuden also contributed to the reduction of CO_2 emissions, but it could not offset the emissions increase caused by the shutdown of nuclear power plants. (author)

  11. New DSM-5 PTSD guilt and shame symptoms among Italian earthquake survivors: Impact on maladaptive behaviors.

    Science.gov (United States)

    Carmassi, Claudia; Bertelloni, Carlo Antonio; Gesi, Camilla; Conversano, Ciro; Stratta, Paolo; Massimetti, Gabriele; Rossi, Alessandro; Dell'Osso, Liliana

    2017-05-01

    Important changes were introduced concerning posttraumatic-stress disorder (PTSD) by the DSM-5 recognizing the role of negative emotions such as guilt and shame, but little evidence is yet available on their prevalence in population assessed by means of DSM-5 criteria. In this study we explored the rates of guilt and shame DSM-5 PTSD diagnostic symptoms among Italian survivors to a massive earthquake and their possible correlation with PTSD and maladaptive behaviors. 869 residents of the town of L'Aquila exposed to the earthquake of April 6th, 2009 were investigated by the Trauma and Loss Spectrum-Self Report (TALS-SR) with particular attention to guilt and shame feelings. DSM-5 symptomatological PTSD was reported by 41.7% of survivors, further 11.6% endorsed at least one guilt/shame symptoms, with significantly higher rates of endorsement were in PTSD respect to No-PTSD subjects, and in the subgroup with at least one maladaptive behavior respect to those with none. There was a significant main effects of PTSD and at least one guilt/shame symptom on TALS-SR symptomatological domains. Mean TALS-SR Maladaptive coping domain score appeared significantly higher in the subgroup with at least one guilt/shame symptom. Further study are needed to investigate guilt and shame feelings in survivors to a natural disaster. Copyright © 2017 Elsevier Ireland Ltd. All rights reserved.

  12. Field guides for excursions to the Nevado del Ruiz Volcano and to the Romeral Fault System (Colombia, in the frame of the Neotectonics of arc-continent collision concepts

    Directory of Open Access Journals (Sweden)

    Borrero Carlos

    2011-06-01

    Full Text Available Central Cordillera of Colombia near to the Nevado del Ruiz volcano, is a seismically active area above the subducting slab of the Nazca plate and deforming upper crust of the Andes. Buildings in the region require strengthening against the effects of both types of hazards: earthquakes and volcanoes. During these trips, we will discuss the 13
    November, 1985, Nevado del Ruiz Volcano eruption that destroyed the Armero city with about 22,000 deceases, as well the 25 January, 1999, Armenia earthquake (M 6.2 that killed about 2000 people and injured 4000 largely as the result of older, poorly 3 constructed buildings. The economic impact of the quake on the region was significant with about 8000 coffee farms either completely or partially destroyed and over 13,000 structures either partially damaged or completely destroyed.
    Both phenomena are associated to a large-transversal structure termed Caldas tear, which is controlling strong motion earthquakes and the Quaternary volcanism of the northern Andes.

  13. The impact of Hurricane Hugo and the San Francisco earthquake on a sample of people with rheumatoid arthritis.

    Science.gov (United States)

    Grady, K E; Reisine, S T; Fifield, J; Lee, N R; McVay, J; Kelsey, M E

    1991-06-01

    The health effects of two natural disasters on 32 people with rheumatoid arthritis (RA) were assessed during the second-year wave of interviews in an ongoing 3-year study. Although the severity of Hurricane Hugo exceeded that of the San Francisco earthquake, no significant differences in health impacts were found. Both groups reported significantly increased ratings of RA activity, pain, and depression compared with ratings during the first year. However, comparison with the rest of the sample (n = 767) showed that increases in disease activity and pain were a general phenomenon but that the increase in depression was unique to the disaster subsample. Physician health status assessments also indicated that those who experienced the disaster were more likely to be classified in later stages of the disease subsequent to the disaster and were more likely to experience flares. These results suggest that people with RA may constitute a special high-risk population for adverse health effects after natural disasters.

  14. Visions of Volcanoes

    Directory of Open Access Journals (Sweden)

    David M. Pyle

    2017-12-01

    Full Text Available The long nineteenth century marked an important transition in the understanding of the nature of combustion and fire, and of volcanoes and the interior of the earth. It was also a period when dramatic eruptions of Vesuvius lit up the night skies of Naples, providing ample opportunities for travellers, natural philosophers, and early geologists to get up close to the glowing lavas of an active volcano. This article explores written and visual representations of volcanoes and volcanic activity during the period, with the particular perspective of writers from the non-volcanic regions of northern Europe. I explore how the language of ‘fire’ was used in both first-hand and fictionalized accounts of peoples’ interactions with volcanoes and experiences of volcanic phenomena, and see how the routine or implicit linkage of ‘fire’ with ‘combustion’ as an explanation for the deep forces at play within and beneath volcanoes slowly changed as the formal scientific study of volcanoes developed. I show how Vesuvius was used as a ‘model’ volcano in science and literature and how, later, following devastating eruptions in Indonesia and the Caribbean, volcanoes took on a new dimension as contemporary agents of death and destruction.

  15. Determining Volcanic Deformation at San Miguel Volcano, El Salvador by Integrating Radar Interferometry and Seismic Analyses

    Science.gov (United States)

    Schiek, C. G.; Hurtado, J. M.; Velasco, A. A.; Buckley, S. M.; Escobar, D.

    2008-12-01

    From the early 1900's to the present day, San Miguel volcano has experienced many small eruptions and several periods of heightened seismic activity, making it one of the most active volcanoes in the El Salvadoran volcanic chain. Prior to 1969, the volcano experienced many explosive eruptions with Volcano Explosivity Indices (VEI) of 2. Since then, eruptions have decreased in intensity to an average VEI of 1. Eruptions mostly consist of phreatic explosions and central vent eruptions. Due to the explosive nature of this volcano, it is important to study the origins of the volcanism and its relationship to surface deformation and earthquake activity. We analyze these interactions by integrating interferometric synthetic aperture radar (InSAR) results with earthquake source location data from a ten-month (March 2007-January 2008) seismic deployment. The InSAR results show a maximum of 7 cm of volcanic inflation from March 2007 to mid-October 2007. During this time, seismic activity increased to a Real-time Seismic-Amplitude Measurement (RSAM) value of >400. Normal RSAM values for this volcano are earthquakes that occurred between March 2007 and January 2008 suggests a fault zone through the center of the San Miguel volcanic cone. This fault zone is most likely where dyke propagation is occurring. Source mechanisms will be determined for the earthquakes associated with this fault zone, and they will be compared to the InSAR deformation field to determine if the mid-October seismic activity and observed surface deformation are compatible.

  16. The impact of internal displacement on child mortality in post-earthquake Haiti: a difference-in-differences analysis.

    Science.gov (United States)

    Chen, Bradley; Halliday, Timothy J; Fan, Victoria Y

    2016-07-19

    The Haiti earthquake in 2010 resulted in 1.5 million internally displaced people (IDP), yet little is known about the impact of displacement on health. In this study, we estimate the impact of displacement on infant and child mortality and key health-behavior mechanisms. We employ a difference-in-differences (DID) design with coarsened exact matching (CEM) to ensure comparability among groups with different displacement status using the 2012 Haiti Demographic and Health Survey (DHS). The participants are 21,417 births reported by a nationally representative sample of 14,287 women aged 15-49. The main independent variables are household displacement status which includes households living in camps, IDP households (not in camps), and households not displaced. The main outcomes are infant and child mortality; health status (height-for-age, anemia); uptake of public health interventions (bed net use, spraying against mosquitoes, and vaccinations); and other conditions (hunger; cholera). Births from the camp households have higher infant mortality (OR = 2.34, 95 % CI 1.15 to 4.75) and child mortality (OR = 2.34, 95 % CI 1.10 to 5.00) than those in non-camp IDP households following the earthquake. These odds are higher despite better access to food, water, bed net use, mosquito spraying, and vaccines among camp households. IDP populations are heterogeneous and households that are displaced outside of camps may be self-selected or self-insured. Meanwhile, even households not displaced by a disaster may face challenges in access to basic necessities and health services. Efforts are needed to identify vulnerable populations to provide targeted assistance in post-disaster relief.

  17. LONG-TERM CULTURAL IMPACTS OF DISASTER DECISION-MAKING: The Case of Post Earthquake Reconstruction in Marathwada, India

    Directory of Open Access Journals (Sweden)

    Rohit Jigyasu

    2013-11-01

    Full Text Available Emergency situations are special since they present decision makers with a context that is characterized by extraordinary constraints on resources, need for urgency of actions and a critical psychosocial state that is markedly different than the normal situation. However, actions taken under these extraordinary situations can have a profound bearing on the longterm recovery of the community and its heritage. This paper considers the critical aspects of decision-making in emergency situations that need to be considered for sustainable longterm recovery of cultural heritage. It is difficult however to judge these essential considerations beforehand without evaluating the impacts of these decisions in hindsight. These considerations will be illustrated through case study of post-earthquake reconstruction in Marathwada in India by assessing the long-term impact of rehabilitation policies formulated in the immediate aftermath of the earthquake. Patterns of adaptation and change in these areas demonstrate how small decisions taken during emergency can have wider socio-economic and physical implications. These cases will also show the importance of understanding the local context, especially with respect to local vulnerabilities as well as capacities, skills and resources while making decisions. These would also emphasize the necessity and ways of engaging various stakeholders, especially the local community, not as passive recipients but as important actors in the decision-making process. These considerations are significant for conservation professionals making decisions during emergencies, especially with regards to immediate protection, repairs and long-term recovery of cultural heritage, while we largely remain at the periphery of the reconstruction process.

  18. Potential impacts of projected climate change on vegetation-management strategies in Hawai‘i Volcanoes National Park

    Science.gov (United States)

    Camp, Richard J.; Berkowitz, S. Paul; Brink, Kevin W.; Jacobi, James D.; Loh, Rhonda; Price, Jonathan; Fortini, Lucas B.

    2018-06-05

    Climate change is expected to alter the seasonal and annual patterns of rainfall and temperature in the Hawaiian Islands. Land managers and other responsible agencies will need to know how plant-species habitats will change over the next century in order to manage these resources effectively. This issue is a major concern for resource managers at Hawai‘i Volcanoes National Park (HAVO), where currently managed Special Ecological Areas (SEAs) for important plant species and communities may no longer provide suitable habitats in the future as the climate changes. Expanding invasive-species distributions also may pose a threat to areas where native plants currently predominate.The objective of this project was to combine recent climate-modeling efforts for the state of Hawai‘i with existing models of plant-species distribution in order to forecast suitable habitat ranges under future climate conditions derived from the Coupled Model Intercomparison Project, phase 3 (CMIP3) global circulation model that was dynamically downscaled for the Hawaiian Islands by using the Hawai‘i Regional Climate Model (HRCM). The HRCM uses the A1B emission scenario (a median future climate projection) from the Special Report on Emissions Scenarios (SRES). On the basis of this model, maps showing projected plant-species ranges were generated for four years as snapshots in time (2000, 2040, 2070, 2090) and for three different trajectories of climate change (gradual, linear, rapid) between the present and future.We mapped probabilistic surfaces of suitable habitat for 39 plant species (both native and alien [nonnative]) identified as being of interest to HAVO resource managers. We displayed these surfaces in terms of change relative to present conditions, whether the range of a given plant species was expected to contract, expand, or remain the same in the future. Within HAVO, approximately two-thirds (18 of 29) of the modeled native plant species were projected to contract in range

  19. Impact of Stylistic Features, Architectural and Urban Rules of the Algiers Architectural Heritage Dating Between 1830 and 1930 ON the Strength of its Buildings during the Earthquake

    Science.gov (United States)

    Souami, M. A.

    2013-07-01

    In a other work, we have highlighted a theoretical point of view that there is an relation between the earthquake-resistant architectural design codes and, the urban and stylistic characteristics of buildings and urban forms of the Algiers architectural heritage dating between 1830 and 1930. Following this, we hypothesized that its various stylistic and urban characteristics have a direct impact on the resilience of buildings to earthquakes. The purpose of this article is to try through the computer simulation examples of some stylistic and urban characteristics to prove the validity or not of our hypothesis.

  20. Volcano hazards in the San Salvador region, El Salvador

    Science.gov (United States)

    Major, J.J.; Schilling, S.P.; Sofield, D.J.; Escobar, C.D.; Pullinger, C.R.

    2001-01-01

    communities. Another concern is a landslide and an associated debris flow (a watery flow of mud, rock, and debris--also known as a lahar) that could occur during periods of no volcanic activity. An event of this type occurred in 1998 at Casita volcano in Nicaragua when extremely heavy rainfall from Hurricane Mitch triggered a landslide that moved down slope and transformed into a rapidly moving debris flow that destroyed two villages and killed more than 2000 people. Historical landslides up to a few hundred thousand cubic meters in volume have been triggered on San Salvador volcano by torrential rainstorms and earthquakes, and some have transformed into debris flows that have inundated populated areas down stream. Destructive rainfall- and earthquake-triggered landslides and debris flows on or near San Salvador volcano in September 1982 and January 2001 demonstrate that such mass movements in El Salvador have also been lethal. This report describes the kinds of hazardous events that occur at volcanoes in general and the kinds of hazardous geologic events that have occurred at San Salvador volcano in the past. The accompanying volcano-hazards-zonation maps show areas that are likely to be at risk when hazardous events occur again.

  1. Impact of DSM-5 PTSD and gender on impaired eating behaviors in 512 Italian earthquake survivors.

    Science.gov (United States)

    Carmassi, Claudia; Antonio Bertelloni, Carlo; Massimetti, Gabriele; Miniati, Mario; Stratta, Paolo; Rossi, Alessandro; Dell Osso, Liliana

    2015-01-30

    Considerable comorbidity rates between Post-traumatic Stress Disorder (PTSD) and eating disorders have been recently reported, as well as increased obesity and underweight conditions. The aim of the present study was to investigate the possible associations between DSM-5 PTSD, gender and impaired eating habits in a sample of 512 Italian earthquake survivors evaluated by the Trauma and Loss Spectrum-Self Report (TALS-SR) and the Mood Spectrum-Self Report (MOODS-SR). Alterations in eating behaviors were assessed by means of four MOODS-SR items: n=150 (…there was no food that appealed to you or tasted good to you?), n=151 (…you constantly craved sweets or carbohydrates?), n=152 (…your appetite or weight decreased?), n=153 (…your appetite or weight increased?). In a Decision Tree procedure subjects with PTSD with respect to those without and, in the No-PTSD subgroup, females with respect to males, had a significantly higher ratio of at least one MOODS-SR eating behavior item (MOODS-SR EB). In the No-PTSD subgroup only, subjects with at least one MOODS-SR EB presented a significantly higher mean TALS-SR symptomatological domains total score with respect to those without MOODS-SR EB. In conclusion, alterations in eating behaviors were associated with PTSD after the L׳Aquila earthquake; among survivors without PTSD significant a correlation emerged between MOODS-SR EB and PTSD symptoms. Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.

  2. Three-axial Fiber Bragg Grating Strain Sensor for Volcano Monitoring

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    Giacomelli, Umberto; Beverini, Nicolò; Carbone, Daniele; Carelli, Giorgio; Francesconi, Francesco; Gambino, Salvatore; Maccioni, Enrico; Morganti, Mauro; Orazi, Massimo; Peluso, Rosario; Sorrentino, Fiodor

    2017-04-01

    Fiber optic and FBGs sensors have attained a large diffusion in the last years as cost-effective monitoring and diagnostic devices in civil engineering. However, in spite of their potential impact, these instruments have found very limited application in geophysics. In order to study earthquakes and volcanoes, the measurement of crustal deformation is of crucial importance. Stress and strain behaviour is among the best indicators of changes in the activity of volcanoes .. Deep bore-hole dilatometers and strainmeters have been employed for volcano monitoring. These instruments are very sensitive and reliable, but are not cost-effective and their installation requires a large effort. Fiber optic based devices offer low cost, small size, wide frequency band, easier deployment and even the possibility of creating a local network with several sensors linked in an array. We present the realization, installation and first results of a shallow-borehole (8,5 meters depth) three-axial Fiber Bragg Grating (FBG) strain sensor prototype. This sensor has been developed in the framework of the MED-SUV project and installed on Etna volcano, in the facilities of the Serra La Nave astrophysical observatory. The installation siteis about 7 Km South-West of the summit craters, at an elevation of about 1740 m. The main goal of our work is the realization of a three-axial device having a high resolution and accuracy in static and dynamic strain measurements, with special attention to the trade-off among resolution, cost and power consumption. The sensor structure and its read-out system are innovative and offer practical advantages in comparison with traditional strain meters. Here we present data collected during the first five months of operation. In particular, the very clear signals recorded in the occurrence of the Central Italy seismic event of October 30th demonstrate the performances of our device.

  3. Continuous monitoring of volcanoes with borehole strainmeters

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    Linde, Alan T.; Sacks, Selwyn

    Monitoring of volcanoes using various physical techniques has the potential to provide important information about the shape, size and location of the underlying magma bodies. Volcanoes erupt when the pressure in a magma chamber some kilometers below the surface overcomes the strength of the intervening rock, resulting in detectable deformations of the surrounding crust. Seismic activity may accompany and precede eruptions and, from the patterns of earthquake locations, inferences may be made about the location of magma and its movement. Ground deformation near volcanoes provides more direct evidence on these, but continuous monitoring of such deformation is necessary for all the important aspects of an eruption to be recorded. Sacks-Evertson borehole strainmeters have recorded strain changes associated with eruptions of Hekla, Iceland and Izu-Oshima, Japan. Those data have made possible well-constrained models of the geometry of the magma reservoirs and of the changes in their geometry during the eruption. The Hekla eruption produced clear changes in strain at the nearest instrument (15 km from the volcano) starting about 30 minutes before the surface breakout. The borehole instrument on Oshima showed an unequivocal increase in the amplitude of the solid earth tides beginning some years before the eruption. Deformational changes, detected by a borehole strainmeter and a very long baseline tiltmeter, and corresponding to the remote triggered seismicity at Long Valley, California in the several days immediately following the Landers earthquake are indicative of pressure changes in the magma body under Long Valley, raising the question of whether such transients are of more general importance in the eruption process. We extrapolate the experience with borehole strainmeters to estimate what could be learned from an installation of a small network of such instruments on Mauna Loa. Since the process of conduit formation from the magma sources in Mauna Loa and other

  4. The effects of spatially varying earthquake impacts on mood and anxiety symptom treatments among long-term Christchurch residents following the 2010/11 Canterbury earthquakes, New Zealand.

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    Hogg, Daniel; Kingham, Simon; Wilson, Thomas M; Ardagh, Michael

    2016-09-01

    This study investigates the effects of disruptions to different community environments, community resilience and cumulated felt earthquake intensities on yearly mood and anxiety symptom treatments from the New Zealand Ministry of Health's administrative databases between September 2009 and August 2012. The sample includes 172,284 long-term residents from different Christchurch communities. Living in a better physical environment was associated with lower mood and anxiety treatment rates after the beginning of the Canterbury earthquake sequence whereas an inverse effect could be found for social community environment and community resilience. These results may be confounded by pre-existing patterns, as well as intensified treatment-seeking behaviour and intervention programmes in severely affected areas. Nevertheless, the findings indicate that adverse mental health outcomes can be found in communities with worse physical but stronger social environments or community resilience post-disaster. Also, they do not necessarily follow felt intensities since cumulative earthquake intensity did not show a significant effect. Copyright © 2016 Elsevier Ltd. All rights reserved.

  5. ACTIVITY AND Vp/Vs RATIO OF VOLCANO-TECTONIC SEISMIC SWARM ZONES AT NEVADO DEL RUIZ VOLCANO, COLOMBIA

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    Londoño B. John Makario

    2010-06-01

    Full Text Available An analysis of the seismic activity for volcano-tectonic earthquake (VT swarms zones at Nevado del Ruiz Volcano (NRV was carried out for the interval 1985- 2002, which is the most seismic active period at NRV until now (2010. The swarm-like seismicity of NRV was frequently concentrated in very well defined clusters around the volcano. The seismic swarm zone located at the active crater was the most active during the entire time. The seismic swarm zone located to the west of the volcano suggested some relationship with the volcanic crises. It was active before and after the two eruptions occurred in November 1985 and September 1989. It is believed that this seismic activity may be used as a monitoring tool of volcanic activity. For each seismic swarm zone the Vp/Vs ratio was also calculated by grouping of earthquakes and stations. It was found that each seismic swarm zone had a distinct Vp/Vs ratio with respect to the others, except for the crater and west swarm zones, which had the same value. The average Vp/Vs ratios for the seismic swarm zones located at the active crater and to the west of the volcano are about 6-7% lower than that for the north swarm zone, and about 3% lower than that for the south swarm zone. We suggest that the reduction of the Vp/Vs ratio is due to degassing phenomena inside the central and western earthquake swarm zones, or due to the presence of microcracks inside the volcano. This supposition is in agreement with other studies of geophysics, geochemistry and drilling surveys carried out at NRV.

  6. Deep magma transport at Kilauea volcano, Hawaii

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    Wright, T.L.; Klein, F.W.

    2006-01-01

    The shallow part of Kilauea's magma system is conceptually well-understood. Long-period and short-period (brittle-failure) earthquake swarms outline a near-vertical magma transport path beneath Kilauea's summit to 20 km depth. A gravity high centered above the magma transport path demonstrates that Kilauea's shallow magma system, established early in the volcano's history, has remained fixed in place. Low seismicity at 4-7 km outlines a storage region from which magma is supplied for eruptions and intrusions. Brittle-failure earthquake swarms shallower than 5 km beneath the rift zones accompany dike emplacement. Sparse earthquakes extend to a decollement at 10-12 km along which the south flank of Kilauea is sliding seaward. This zone below 5 km can sustain aseismic magma transport, consistent with recent tomographic studies. Long-period earthquake clusters deeper than 40 km occur parallel to and offshore of Kilauea's south coast, defining the deepest seismic response to magma transport from the Hawaiian hot spot. A path connecting the shallow and deep long-period earthquakes is defined by mainshock-aftershock locations of brittle-failure earthquakes unique to Kilauea whose hypocenters are deeper than 25 km with magnitudes from 4.4 to 5.2. Separation of deep and shallow long-period clusters occurs as the shallow plumbing moves with the volcanic edifice, while the deep plumbing is centered over the hotspot. Recent GPS data agrees with the volcano-propagation vector from Kauai to Maui, suggesting that Pacific plate motion, azimuth 293.5?? and rate of 7.4 cm/yr, has been constant over Kilauea's lifetime. However, volcano propagation on the island of Hawaii, azimuth 325??, rate 13 cm/yr, requires southwesterly migration of the locus of melting within the broad hotspot. Deep, long-period earthquakes lie west of the extrapolated position of Kilauea backward in time along a plate-motion vector, requiring southwesterly migration of Kilauea's magma source. Assumed ages of 0

  7. Advances in volcano monitoring and risk reduction in Latin America

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    McCausland, W. A.; White, R. A.; Lockhart, A. B.; Marso, J. N.; Assitance Program, V. D.; Volcano Observatories, L. A.

    2014-12-01

    We describe results of cooperative work that advanced volcanic monitoring and risk reduction. The USGS-USAID Volcano Disaster Assistance Program (VDAP) was initiated in 1986 after disastrous lahars during the 1985 eruption of Nevado del Ruiz dramatizedthe need to advance international capabilities in volcanic monitoring, eruption forecasting and hazard communication. For the past 28 years, VDAP has worked with our partners to improve observatories, strengthen monitoring networks, and train observatory personnel. We highlight a few of the many accomplishments by Latin American volcano observatories. Advances in monitoring, assessment and communication, and lessons learned from the lahars of the 1985 Nevado del Ruiz eruption and the 1994 Paez earthquake enabled the Servicio Geológico Colombiano to issue timely, life-saving warnings for 3 large syn-eruptive lahars at Nevado del Huila in 2007 and 2008. In Chile, the 2008 eruption of Chaitén prompted SERNAGEOMIN to complete a national volcanic vulnerability assessment that led to a major increase in volcano monitoring. Throughout Latin America improved seismic networks now telemeter data to observatories where the decades-long background rates and types of seismicity have been characterized at over 50 volcanoes. Standardization of the Earthworm data acquisition system has enabled data sharing across international boundaries, of paramount importance during both regional tectonic earthquakes and during volcanic crises when vulnerabilities cross international borders. Sharing of seismic forecasting methods led to the formation of the international organization of Latin American Volcano Seismologists (LAVAS). LAVAS courses and other VDAP training sessions have led to international sharing of methods to forecast eruptions through recognition of precursors and to reduce vulnerabilities from all volcano hazards (flows, falls, surges, gas) through hazard assessment, mapping and modeling. Satellite remote sensing data

  8. LOCAL SITE CONDITIONS INFLUENCING EARTHQUAKE INTENSITIES AND SECONDARY COLLATERAL IMPACTS IN THE SEA OF MARMARA REGION - Application of Standardized Remote Sensing and GIS-Methods in Detecting Potentially Vulnerable Areas to Earthquakes, Tsunamis and Other Hazards.

    Directory of Open Access Journals (Sweden)

    George Pararas-Carayannis

    2011-01-01

    Full Text Available The destructive earthquake that struck near the Gulf of Izmit along the North Anatolian fault in Northwest Turkey on August 17, 1999, not only generated a local tsunami that was destructive at Golcuk and other coastal cities in the eastern portion of the enclosed Sea of Marmara, but was also responsible for extensive damage from collateral hazards such as subsidence, landslides, ground liquefaction, soil amplifications, compaction and underwater slumping of unconsolidated sediments. This disaster brought attention in the need to identify in this highly populated region, local conditions that enhance earthquake intensities, tsunami run-up and other collateral disaster impacts. The focus of the present study is to illustrate briefly how standardized remote sensing techniques and GIS-methods can help detect areas that are potentially vulnerable, so that disaster mitigation strategies can be implemented more effectively. Apparently, local site conditions exacerbate earthquake intensities and collateral disaster destruction in the Marmara Sea region. However, using remote sensing data, the causal factors can be determined systematically. With proper evaluation of satellite imageries and digital topographic data, specific geomorphologic/topographic settings that enhance disaster impacts can be identified. With a systematic GIS approach - based on Digital Elevation Model (DEM data - geomorphometric parameters that influence the local site conditions can be determined. Digital elevation data, such as SRTM (Shuttle Radar Topography Mission, with 90m spatial resolution and ASTER-data with 30m resolution, interpolated up to 15 m is readily available. Areas with the steepest slopes can be identified from slope gradient maps. Areas with highest curvatures susceptible to landslides can be identified from curvature maps. Coastal areas below the 10 m elevation susceptible to tsunami inundation can be clearly delineated. Height level maps can also help locate

  9. Long-term impact of earthquake stress on fasting glucose control and diabetes prevalence among Chinese adults of Tangshan

    OpenAIRE

    An, Cuixia; Zhang, Yun; Yu, Lulu; Li, Na; Song, Mei; Wang, Lan; Zhao, Xiaochuan; Gao, Yuanyuan; Wang, Xueyi

    2014-01-01

    Objective: To investigate the long-term influence of stresses from the 1976 Tangshan earthquake on blood glucose control and the incidence of diabetes mellitus in Chinese people of Tangshan. Methods: 1,551 adults ≥ 37 years of age were recruited for this investigation in Tangshan city of China, where one of the deadliest earthquakes occurred in 1796. All subjects finished a questionnaire. 1,030 of them who experienced that earthquake were selected into the exposure group, while 521 were gathe...

  10. Effects of Volcanoes on the Natural Environment

    Science.gov (United States)

    Mouginis-Mark, Peter J.

    2005-01-01

    The primary focus of this project has been on the development of techniques to study the thermal and gas output of volcanoes, and to explore our options for the collection of vegetation and soil data to enable us to assess the impact of this volcanic activity on the environment. We originally selected several volcanoes that have persistent gas emissions and/or magma production. The investigation took an integrated look at the environmental effects of a volcano. Through their persistent activity, basaltic volcanoes such as Kilauea (Hawaii) and Masaya (Nicaragua) contribute significant amounts of sulfur dioxide and other gases to the lower atmosphere. Although primarily local rather than regional in its impact, the continuous nature of these eruptions means that they can have a major impact on the troposphere for years to decades. Since mid-1986, Kilauea has emitted about 2,000 tonnes of sulfur dioxide per day, while between 1995 and 2000 Masaya has emotted about 1,000 to 1,500 tonnes per day (Duffel1 et al., 2001; Delmelle et al., 2002; Sutton and Elias, 2002). These emissions have a significant effect on the local environment. The volcanic smog ("vog" ) that is produced affects the health of local residents, impacts the local ecology via acid rain deposition and the generation of acidic soils, and is a concern to local air traffic due to reduced visibility. Much of the work that was conducted under this NASA project was focused on the development of field validation techniques of volcano degassing and thermal output that could then be correlated with satellite observations. In this way, we strove to develop methods by which not only our study volcanoes, but also volcanoes in general worldwide (Wright and Flynn, 2004; Wright et al., 2004). Thus volcanoes could be routinely monitored for their effects on the environment. The selected volcanoes were: Kilauea (Hawaii; 19.425 N, 155.292 W); Masaya (Nicaragua; 11.984 N, 86.161 W); and Pods (Costa Rica; 10.2OoN, 84.233 W).

  11. Dynamic triggering of volcano drumbeat-like seismicity at the Tatun volcano group in Taiwan

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    Lin, Cheng-Horng

    2017-07-01

    Periodical seismicity during eruptions has been observed at several volcanoes, such as Mount St. Helens and Soufrière Hills. Movement of magma is often considered one of the most important factors in its generation. Without any magma movement, drumbeat-like (or heartbeat-like) periodical seismicity was detected twice beneath one of the strongest fumarole sites (Dayoukeng) among the Tatun volcano group in northern Taiwan in 2015. Both incidences of drumbeat-like seismicity were respectively started after felt earthquakes in Taiwan, and then persisted for 1-2 d afterward with repetition intervals of ∼18 min between any two adjacent events. The phenomena suggest both drumbeat-like (heartbeat-like) seismicity sequences were likely triggered by dynamic waves generated by the two felt earthquakes. Thus, rather than any involvement of magma, a simplified pumping system within a degassing conduit is proposed to explain the generation of drumbeat-like seismicity. The collapsed rocks within the conduit act as a piston, which was repeatedly lifted up by ascending gas from a deeper reservoir and dropped down when the ascending gas was escaping later. These phenomena show that the degassing process is still very strong in the Tatun volcano group in Taiwan, even though it has been dormant for about several thousand years.

  12. After the Earthquake: Impacts of Seismic Snow and Ice Redistribution in Langtang Valley, Nepal, on Glacier Mass Balances and Hydrological Regimes

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    Shea, J. M.; Ragettli, S.; Immerzeel, W.; Pellicciotti, F.; Miles, E. S.; Steiner, J. F.; Buri, P.; Kraaijenbrink, P. D. A.

    2015-12-01

    The magnitude 7.8 Gorkha Earthquake that struck Nepal on 25 April 2015 resulted in a catastrophic loss of life and property, and had major impacts in high mountain areas. The earthquake resulted in a number of massive ice avalanches in Langtang Valley that destroyed entire villages and killed over 300 people. We first conduct a remote sensing analysis of the entire catchment, and attempt to quantify the volumes of snow and ice redistributed through high-resolution optical imagery, thermal imagery, and DEM differencing. Where data are available we examine the impact on the surface mass balances of four major glaciers (Lirung, Shalbachaum, Langtang and Langshisha). Finally, we use the physically-based and fully distributed TOPKAPI model to simulate the impacts of the co-seismic snow and ice redistribution on the hydrology of the Langtang River.

  13. Integrated Application of Remote Sensing, GIS and Hydrological Modeling to Estimate the Potential Impact Area of Earthquake-Induced Dammed Lakes

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    Bo Cao

    2017-10-01

    Full Text Available Dammed lakes are an important secondary hazard caused by earthquakes. They can induce further damage to nearby humans. Current hydrology calculation research on dammed lakes usually lacks spatial expressive ability and cannot accurately conduct impact assessment without the support of remote sensing, which obtains important characteristic information of dammed lakes. The current study aims to address the issues of the potential impact area estimate of earthquake-induced dammed lakes by combining remote sensing (RS, a geographic information system (GIS, and hydrological modeling. The Tangjiashan dammed lake induced by the Wenchuan earthquake was selected as the case for study. The elevation-versus-reservoir capacity curve was first calculated using the seed-growing algorithm based on digital elevation model (DEM data. The simulated annealing algorithm was applied to train the hydrological modeling parameters according to the historical hydrologic data. Then, the downstream water elevation variational process under different collapse capacity conditions was performed based on the obtained parameters. Finally, the downstream potential impact area was estimated by the highest water elevation values at different hydrologic sections. Results show that a flood with a collapse elevation of at least 680 m will impact the entire downstream region of Beichuan town. We conclude that spatial information technology combined with hydrological modeling can accurately predict and demonstrate the potential impact area with limited data resources. This paper provides a better guide for future immediate responses to dammed lake hazard mitigation.

  14. Recent Seismicity in the Ceboruco Volcano, Western Mexico

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    Nunez, D.; Chávez-Méndez, M. I.; Nuñez-Cornu, F. J.; Sandoval, J. M.; Rodriguez-Ayala, N. A.; Trejo-Gomez, E.

    2017-12-01

    The Ceboruco volcano is the largest (2280 m.a.s.l) of several volcanoes along the Tepic-Zacoalco rift zone in Nayarit state (Mexico). During the last 1000 years, this volcano had effusive-explosive episodes with eight eruptions providing an average of one eruption each 125 years. Since the last eruption occurred in 1870, 147 years ago, a new eruption likelihood is really high and dangerous due to nearby population centers, important roads and lifelines that traverse the volcano's slopes. This hazards indicates the importance of monitoring the seismicity associated with the Ceboruco volcano whose ongoing activity is evidenced by fumaroles and earthquakes. During 2003 and 2008, this region was registered by just one Lennartz Marslite seismograph featuring a Lennartz Le3D sensor (1 Hz) [Rodríguez Uribe et al. (2013)] where they observed that seismicity rates and stresses appear to be increasing indicating higher levels of activity within the volcano. Until July 2017, a semi-permanent network with three Taurus (Nanometrics) and one Q330 Quanterra (Kinemetrics) digitizers with Lennartz 3Dlite sensors of 1 Hz natural frequency was registering in the area. In this study, we present the most recent seismicity obtained by the semi-permanent network and a temporary network of 21 Obsidians 4X and 8X (Kinemetrics) covering an area of 16 km x 16 km with one station every 2.5-3 km recording from November 2016 to July 2017.

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

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

    2015-10-01

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

  16. Geoheritage value of the UNESCO site at Leon Viejo and Momotombo volcano, Nicaragua

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    van Wyk de Vries, Benjamin; Navarro, Martha; Espinoza, Eveling; Delgado, Hugo

    2017-04-01

    The Momotombo volcano has a special place in the history of Nicaragua. It is perfectly visible from the Capital, Managua, and from the major city of Leon. The old capital "Leon Viejo", founded in 1524 was abandoned in 1610, after a series of earthquakes and some major eruptions from Momotombo. The site was subsequently covered by Momotombo ash. A major geothermal power plant stands at the base of the volcano. Momotombo had been dormant for a hundred years, but had maintained high fumarole temperatures (900°C), indicating magma had been close to the surface for decades. In recent years, seismic activity has increased around the volcano. In December 2015, after a short ash eruption phase the volcano erupted lava, then a string of Vulcanian explosions. The volcano is now in a phase of small Vulcanian explosions and degassing. The Leon Viejo World Heritage site is at risk to mainly ash fall from the volcano, but the abandonment of the old city was primarily due to earthquakes. Additional risks come from high rainfall during hurricanes. There is an obvious link between the cultural site (inscribed under UNESCO cultural criteria) and the geological environment. First, the reactivation of Momotombo volcano makes it more important to revise the hazard of the site. At the same time, Leon Viejo can provide a portal for outreach related to the volcano and for geological risk in general. To maximise this, we provide a geosite inventory of the main features of Momotombo, and it's environs, that can be used as the first base for such studies. The volcano was visited by many adventure tourists before the 2015/2016 eruption, but is out of bounds at present. Alternative routes, around the volcano could be made, to adapt to the new situation and to show to visitors more of the geodiversity of this fascinating volcano-tectonic and cultural area.

  17. Ionospheric GPS TEC Anomalies and M >= 5.9 Earthquakes in Indonesia during 1993 - 2002

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    Sarmoko Saroso

    2008-01-01

    Full Text Available Indonesia is one of the most seismically active regions in the world, containing numerous active volcanoes and subject to frequent earthquakes with epicenters distributed along the same regions as volcanoes. In this paper, a case study is carried out to investigate pre-earthquake ionospheric anomalies in total electron content (TEC during the Sulawesi earthquakes of 1993 - 2002, and the Sumatra-Andaman earthquake of 26 December 2004, the largest earthquake in the world since 1964. It is found that the ionospheric TECs remarkably decrease within 2 - 7 days before the earthquakes, and for the very powerful Sumatra-Andaman earthquake, the anomalies extend up to about 1600 km from the epicenter.

  18. San Miguel Volcanic Seismic and Structure in Central America: Insight into the Physical Processes of Volcanoes

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    Patlan, E.; Velasco, A.; Konter, J. G.

    2010-12-01

    The San Miguel volcano lies near the city of San Miguel, El Salvador (13.43N and - 88.26W). San Miguel volcano, an active stratovolcano, presents a significant natural hazard for the city of San Miguel. In general, the internal state and activity of volcanoes remains an important component to understanding volcanic hazard. The main technology for addressing volcanic hazards and processes is through the analysis of data collected from the deployment of seismic sensors that record ground motion. Six UTEP seismic stations were deployed around San Miguel volcano from 2007-2008 to define the magma chamber and assess the seismic and volcanic hazard. We utilize these data to develop images of the earth structure beneath the volcano, studying the volcanic processes by identifying different sources, and investigating the role of earthquakes and faults in controlling the volcanic processes. We initially locate events using automated routines and focus on analyzing local events. We then relocate each seismic event by hand-picking P-wave arrivals, and later refine these picks using waveform cross correlation. Using a double difference earthquake location algorithm (HypoDD), we identify a set of earthquakes that vertically align beneath the edifice of the volcano, suggesting that we have identified a magma conduit feeding the volcano. We also apply a double-difference earthquake tomography approach (tomoDD) to investigate the volcano’s plumbing system. Our preliminary results show the extent of the magma chamber that also aligns with some horizontal seismicity. Overall, this volcano is very active and presents a significant hazard to the region.

  19. The impact of the Great East Japan earthquake on mandatory psychiatric emergency hospitalizations in Tokyo: a retrospective observational study.

    Science.gov (United States)

    Aoki, A; Aoki, Y; Harima, H

    2012-10-09

    On 11 March 2011, the eastern part of Japan was struck by a magnitude 9.0 quake. About 20 000 people were killed or were missing, and a nuclear crisis followed. In Tokyo, people were indirectly exposed to the earthquake and nuclear crisis by TV broadcast. The aim of our study was to evaluate the potential effect of the series of catastrophes on psychiatric emergency hospitalizations in Tokyo. Clinical records of patients who were mandatorily admitted to Tokyo Metropolitan Matsuzawa Hospital by law because of urgent risk to self or others were reviewed. Records regarding the 2 years of investigation, which include the 6 months after the earthquake, were reviewed. The six months after the earthquake were compared with the eighteen months before the earthquake in clinical and demographic data using independent t-tests or χ(2) tests. During the 6 months before and after the earthquake, 97 and 127 people were mandatorily admitted. χ(2) Tests demonstrated a significant increase in the number of patients after the earthquake (P = 0.045), attributable to the significant increase in the number of patients with schizophrenia after the earthquake (P = 0.011, 32 vs 56), whereas there were no significant differences in the number of patients with other diagnoses between those two periods. Independent t-tests revealed that patients admitted after the earthquake had marginally significantly shorter periods of education compared with those admitted before the earthquake (13.78 vs 12.82 years, P = 0.084). This work suggests that patients with schizophrenia were more sensitive to indirect exposure to the earthquake and that a shorter period of education was a potential risk factor.

  20. Global Volcano Model

    Science.gov (United States)

    Sparks, R. S. J.; Loughlin, S. C.; Cottrell, E.; Valentine, G.; Newhall, C.; Jolly, G.; Papale, P.; Takarada, S.; Crosweller, S.; Nayembil, M.; Arora, B.; Lowndes, J.; Connor, C.; Eichelberger, J.; Nadim, F.; Smolka, A.; Michel, G.; Muir-Wood, R.; Horwell, C.

    2012-04-01

    Over 600 million people live close enough to active volcanoes to be affected when they erupt. Volcanic eruptions cause loss of life, significant economic losses and severe disruption to people's lives, as highlighted by the recent eruption of Mount Merapi in Indonesia. The eruption of Eyjafjallajökull, Iceland in 2010 illustrated the potential of even small eruptions to have major impact on the modern world through disruption of complex critical infrastructure and business. The effects in the developing world on economic growth and development can be severe. There is evidence that large eruptions can cause a change in the earth's climate for several years afterwards. Aside from meteor impact and possibly an extreme solar event, very large magnitude explosive volcanic eruptions may be the only natural hazard that could cause a global catastrophe. GVM is a growing international collaboration that aims to create a sustainable, accessible information platform on volcanic hazard and risk. We are designing and developing an integrated database system of volcanic hazards, vulnerability and exposure with internationally agreed metadata standards. GVM will establish methodologies for analysis of the data (eg vulnerability indices) to inform risk assessment, develop complementary hazards models and create relevant hazards and risk assessment tools. GVM will develop the capability to anticipate future volcanism and its consequences. NERC is funding the start-up of this initiative for three years from November 2011. GVM builds directly on the VOGRIPA project started as part of the GRIP (Global Risk Identification Programme) in 2004 under the auspices of the World Bank and UN. Major international initiatives and partners such as the Smithsonian Institution - Global Volcanism Program, State University of New York at Buffalo - VHub, Earth Observatory of Singapore - WOVOdat and many others underpin GVM.

  1. An Earthquake Swarm Search Implemented at Major Convergent Margins to Test for Associated Aseismic Slip

    Science.gov (United States)

    Holtkamp, S. G.; Pritchard, M. E.; Lohman, R. B.; Brudzinski, M. R.

    2009-12-01

    Recent geodetic analysis indicates earthquake swarms may be associated with slow slip such that earthquakes may only represent a fraction of the moment release. To investigate this potential relationship, we have developed a manual search approach to identify earthquake swarms from a seismicity catalog. Our technique is designed to be insensitive to spatial and temporal scales and the total number of events, as seismicity rates vary in different fault zones. Our first application of this technique on globally recorded earthquakes in South America detects 35 possible swarms of varying spatial scale, with 18 in the megathrust region and 8 along the volcanic arc. Three swarms in the vicinity of the arc appear to be triggered by the Mw=8.5 2001 Peru earthquake, and are examined for possible triggering mechanisms. Coulomb stress modeling suggests that static stress changes due to the earthquake are insufficient to trigger activity, so a dynamic or secondary triggering mechanism is more likely. Volcanic swarms are often associated with ground deformation, either associated with fluid movement (e.g. dike intrusion or chamber inflation or deflation) or fault movement, although these processes are sometimes difficult to differentiate. The only swarm along the arc with sufficient geodetic data that we can process and model is near Ticsani Volcano in Peru. In this case, a swarm of events southeast of the volcano precedes a more typical earthquake sequence beneath the volcano, and evidence for deformation is found in the location of the swarm, but there is no evidence for aseismic slip. Rather, we favor a model where the swarm is associated with deflation of a magma body to the southeast that triggered the earthquake sequence by promoting movement on a fault beneath Ticsani. Since swarms on the subduction interface may indicate aseismic moment release, with a direct impact on hazard, we examine potential relations between swarms and megathrust ruptures. We find evidence that

  2. Hawaiian Volcano Observatory seismic data, January to March 2009

    Science.gov (United States)

    Nakata, Jennifer S.; Okubo, Paul G.

    2010-01-01

    This U.S. Geological Survey (USGS), Hawaiian Volcano Observatory (HVO) summary presents seismic data gathered during January–March 2009. The seismic summary offers earthquake hypocenters without interpretation as a source of preliminary data and is complete in that most data for events of M≥1.5 are included. All latitude and longitude references in this report are stated in Old Hawaiian Datum.

  3. Mauna Loa--history, hazards and risk of living with the world's largest volcano

    Science.gov (United States)

    Trusdell, Frank A.

    2012-01-01

    Mauna Loa on the Island Hawaiʻi is the world’s largest volcano. People residing on its flanks face many hazards that come with living on or near an active volcano, including lava flows, explosive eruptions, volcanic smog, damaging earthquakes, and local tsunami (giant seawaves). The County of Hawaiʻi (Island of Hawaiʻi) is the fastest growing County in the State of Hawaii. Its expanding population and increasing development mean that risk from volcano hazards will continue to grow. U.S. Geological Survey (USGS) scientists at the Hawaiian Volcano Observatory (HVO) closely monitor and study Mauna Loa Volcano to enable timely warning of hazardous activity and help protect lives and property.

  4. Do Earthquakes Shake Stock Markets?

    Science.gov (United States)

    Ferreira, Susana; Karali, Berna

    2015-01-01

    This paper examines how major earthquakes affected the returns and volatility of aggregate stock market indices in thirty-five financial markets over the last twenty years. Results show that global financial markets are resilient to shocks caused by earthquakes even if these are domestic. Our analysis reveals that, in a few instances, some macroeconomic variables and earthquake characteristics (gross domestic product per capita, trade openness, bilateral trade flows, earthquake magnitude, a tsunami indicator, distance to the epicenter, and number of fatalities) mediate the impact of earthquakes on stock market returns, resulting in a zero net effect. However, the influence of these variables is market-specific, indicating no systematic pattern across global capital markets. Results also demonstrate that stock market volatility is unaffected by earthquakes, except for Japan.

  5. Cook Inlet and Kenai Peninsula, Alaska ESI: VOLCANOS (Volcano Points)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This data set contains the locations of volcanos in Cook Inlet and Kenai Peninsula, Alaska. Vector points in the data set represent the location of the volcanos....

  6. When probabilistic seismic hazard climbs volcanoes: the Mt. Etna case, Italy – Part 2: Computational implementation and first results

    Directory of Open Access Journals (Sweden)

    L. Peruzza

    2017-11-01

    Full Text Available This paper describes the model implementation and presents results of a probabilistic seismic hazard assessment (PSHA for the Mt. Etna volcanic region in Sicily, Italy, considering local volcano-tectonic earthquakes. Working in a volcanic region presents new challenges not typically faced in standard PSHA, which are broadly due to the nature of the local volcano-tectonic earthquakes, the cone shape of the volcano and the attenuation properties of seismic waves in the volcanic region. These have been accounted for through the development of a seismic source model that integrates data from different disciplines (historical and instrumental earthquake datasets, tectonic data, etc.; presented in Part 1, by Azzaro et al., 2017 and through the development and software implementation of original tools for the computation, such as a new ground-motion prediction equation and magnitude–scaling relationship specifically derived for this volcanic area, and the capability to account for the surficial topography in the hazard calculation, which influences source-to-site distances. Hazard calculations have been carried out after updating the most recent releases of two widely used PSHA software packages (CRISIS, as in Ordaz et al., 2013; the OpenQuake engine, as in Pagani et al., 2014. Results are computed for short- to mid-term exposure times (10 % probability of exceedance in 5 and 30 years, Poisson and time dependent and spectral amplitudes of engineering interest. A preliminary exploration of the impact of site-specific response is also presented for the densely inhabited Etna's eastern flank, and the change in expected ground motion is finally commented on. These results do not account for M  >  6 regional seismogenic sources which control the hazard at long return periods. However, by focusing on the impact of M  <  6 local volcano-tectonic earthquakes, which dominate the hazard at the short- to mid-term exposure times considered

  7. The livelihoods of Haitian health-care providers after the january 2010 earthquake: a pilot study of the economic and quality-of-life impact of emergency relief.

    Science.gov (United States)

    Haar, Rohini J; Naderi, Sassan; Acerra, John R; Mathias, Maxwell; Alagappan, Kumar

    2012-03-02

    An effective international response to a disaster requires cooperation and coordination with the existing infrastructure. In some cases, however, international relief efforts can compete with the local work force and affect the balance of health-care systems already in place. This study seeks to evaluate the impact of the international humanitarian response to the 12 January 2010 earthquake on Haitian health-care providers (HHP). Fifty-nine HHPs were surveyed in August of 2010 using a modified World Health Organization Quality of Life-Brief questionnaire (WHOQoL-B) that included questions on respondents' workload before the earthquake, immediately after, and presently. The study population consisted of physicians, nurses, and technicians at public hospitals, non-governmental organization (NGO) clinics, and private offices in Port-au-Prince, Haiti. Following the earthquake, public hospital and NGO providers reported a significant increase in their workload (15 of 17 and 22 of 26 respondents, respectively). Conversely, 12 of 16 private providers reported a significant decrease in workload (p working a similar number of hours prior to the earthquake (average 40 h/week), they reported working significantly different amounts following the earthquake. Public hospital and NGO providers averaged more than 50 h/week, and private providers averaged just over 33 h/week of employment (p working at public hospitals and NGOs, however, had significantly lower scores on the WHOQoL-B when answering questions about their environment (p work among HHPs. To create a robust health-care system in the long term while meeting short-term needs, humanitarian responses should seek to better integrate existing systems and involve local providers in the design and implementation of an emergency program.

  8. Analysis of the impact of fault mechanism radiation patterns on macroseismic fields in the epicentral area of 1998 and 2004 Krn Mountains earthquakes (NW Slovenia).

    Science.gov (United States)

    Gosar, Andrej

    2014-01-01

    Two moderate magnitude (Mw = 5.6 and 5.2) earthquakes in Krn Mountains occurred in 1998 and 2004 which had maximum intensity VII-VIII and VI-VII EMS-98, respectively. Comparison of both macroseismic fields showed unexpected differences in the epicentral area which cannot be explained by site effects. Considerably, different distribution of the highest intensities can be noticed with respect to the strike of the seismogenic fault and in some localities even higher intensities have been estimated for the smaller earthquake. Although hypocentres of both earthquakes were only 2 km apart and were located on the same seismogenic Ravne fault, their focal mechanisms showed a slight difference: almost pure dextral strike-slip for the first event and a strike-slip with small reverse component on a steep fault plane for the second one. Seismotectonically the difference is explained as an active growth of the Ravne fault at its NW end. The radiation patterns of both events were studied to explain their possible impact on the observed variations in macroseismic fields and damage distribution. Radiation amplitude lobes were computed for three orthogonal directions: radial P, SV, and SH. The highest intensities of both earthquakes were systematically observed in directions of four (1998) or two (2004) large amplitude lobes in SH component (which corresponds mainly to Love waves), which have significantly different orientation for both events. On the other hand, radial P direction, which is almost purely symmetrical for the strike-slip mechanism of 1998 event, showed for the 2004 event that its small reverse component of movement has resulted in a very pronounced amplitude lobe in SW direction where two settlements are located which expressed higher intensities in the case of the 2004 event with respect to the 1998 one. Although both macroseismic fields are very complex due to influences of multiple earthquakes, retrofitting activity after 1998, site effects, and sparse

  9. Volcanoes: Coming Up from Under.

    Science.gov (United States)

    Science and Children, 1980

    1980-01-01

    Provides specific information about the eruption of Mt. St. Helens in March 1980. Also discusses how volcanoes are formed and how they are monitored. Words associated with volcanoes are listed and defined. (CS)

  10. Analog earthquakes

    International Nuclear Information System (INIS)

    Hofmann, R.B.

    1995-01-01

    Analogs are used to understand complex or poorly understood phenomena for which little data may be available at the actual repository site. Earthquakes are complex phenomena, and they can have a large number of effects on the natural system, as well as on engineered structures. Instrumental data close to the source of large earthquakes are rarely obtained. The rare events for which measurements are available may be used, with modfications, as analogs for potential large earthquakes at sites where no earthquake data are available. In the following, several examples of nuclear reactor and liquified natural gas facility siting are discussed. A potential use of analog earthquakes is proposed for a high-level nuclear waste (HLW) repository

  11. Indoor radon and earthquake

    International Nuclear Information System (INIS)

    Saghatelyan, E.; Petrosyan, L.; Aghbalyan, Yu.; Baburyan, M.; Araratyan, L.

    2004-01-01

    For the first time on the basis of the Spitak earthquake of December 1988 (Armenia, December 1988) experience it is found out that the earthquake causes intensive and prolonged radon splashes which, rapidly dispersing in the open space of close-to-earth atmosphere, are contrastingly displayed in covered premises (dwellings, schools, kindergartens) even if they are at considerable distance from the earthquake epicenter, and this multiplies the radiation influence on the population. The interval of splashes includes the period from the first fore-shock to the last after-shock, i.e. several months. The area affected by radiation is larger vs. Armenia's territory. The scale of this impact on population is 12 times higher than the number of people injured in Spitak, Leninakan and other settlements (toll of injured - 25 000 people, radiation-induced diseases in people - over 300 000). The influence of radiation directly correlates with the earthquake force. Such a conclusion is underpinned by indoor radon monitoring data for Yerevan since 1987 (120 km from epicenter) 5450 measurements and multivariate analysis with identification of cause-and-effect linkages between geo dynamics of indoor radon under stable and conditions of Earth crust, behavior of radon in different geological mediums during earthquakes, levels of room radon concentrations and effective equivalent dose of radiation impact of radiation dose on health and statistical data on public health provided by the Ministry of Health. The following hitherto unexplained facts can be considered as consequences of prolonged radiation influence on human organism: long-lasting state of apathy and indifference typical of the population of Armenia during the period of more than a year after the earthquake, prevalence of malignant cancer forms in disaster zones, dominating lung cancer and so on. All urban territories of seismically active regions are exposed to the threat of natural earthquake-provoked radiation influence

  12. The impact of major earthquakes on the psychological functioning of medical students: a Christchurch, New Zealand study.

    Science.gov (United States)

    Carter, Frances A; Bell, Caroline J; Ali, Anthony N; McKenzie, Janice; Wilkinson, Timothy J

    2014-07-18

    No previous studies have systematically assessed the psychological functioning of medical students following a major disaster. To describe the psychological functioning of medical students following the earthquakes in Canterbury, New Zealand, and identify predictors of adverse psychological functioning. 7 months following the most severe earthquake, medical students completed the Depression, Anxiety and Stress Scale (DASS), the Post-Traumatic Stress Disorder Checklist, the Eysenck Personality Questionnaire, the Connor Davidson Resilience Scale, the Work and Adjustment Scale, and Likert scales assessing psychological functioning at worst and currently. A substantial minority of medical students reported moderate-extreme difficulties on the DASS subscales 7 months following the most severe earthquake (Depression =12%; Anxiety =9%; Stress =10%). Multiple linear modelling produced a model that predicted 27% of the variance in total scores on the DASS. Variables contributing significantly to the model were: year of medical course, presence of mental health problems prior to the earthquakes, not being New Zealand European, and being higher on retrospectively rated neuroticism prior to the earthquakes. Around 10% of medical students experienced moderate-extreme psychological difficulties 7 months following the most severe earthquake on 22 February 2011. Specific groups at high risk for ongoing psychological symptomatology were able to be identified.

  13. Seismicity associated with dome growth and collapse at the Soufriere Hills Volcano, Montserrat

    Science.gov (United States)

    Miller, A.D.; Stewart, R.C.; White, R.A.; Luckett, R.; Baptie, B.J.; Aspinall, W.P.; Latchman, J.L.; Lynch, L.L.; Voight, B.

    1998-01-01

    Varied seismicity has accompanied growth and collapse of the lava dome of the Soufriere Hills Volcano, Montserrat. Earthquakes have been classified as either volcano-tectonic, long-period or hybrid, and daily variations in the numbers of events have mapped changes in the style of eruption. Repetitive hybrid earthquakes were common during the first months of dome growth. In July 1996 the style of seismicity changed and regular short-lived hybrid earthquake swarms became common. This change was probably caused by an increase in the magma flux. Earthquake swarms have preceded almost all major dome collapses, and have accompanied cyclical deformation, thought to be due to a built-up of pressure in the upper conduit which is later released by magma moving into the dome.Varied seismicity has accompanied growth and collapse of the lava dome of the Soufriere Hills Volcano, Montserrat. Earthquakes have been classified as either volcano-tectonic, long-period or hybrid, and daily variations in the numbers of events have mapped changes in the style of eruption. Repetitive hybrid earthquakes were common during the first months of dome growth. In July 1996 the style of seismicity changed and regular, short-lived hybrid earthquake swarms became common. This change was probably caused by an increase in the magma flux. Earthquake swarms have preceded almost all major dome collapses, and have accompanied cyclical deformation, thought to be due to a build-up of pressure in the upper conduit which is later released by magma moving into the dome.

  14. Impact of the 2001 Tohoku-oki earthquake to Tokyo Metropolitan area observed by the Metropolitan Seismic Observation network (MeSO-net)

    Science.gov (United States)

    Hirata, N.; Hayashi, H.; Nakagawa, S.; Sakai, S.; Honda, R.; Kasahara, K.; Obara, K.; Aketagawa, T.; Kimura, H.; Sato, H.; Okaya, D. A.

    2011-12-01

    The March 11, 2011 Tohoku-oki earthquake brought a great impact to the Tokyo metropolitan area in both seismological aspect and seismic risk management although Tokyo is located 340 km from the epicenter. The event generated very strong ground motion even in the metropolitan area and resulted severe requifaction in many places of Kanto district. National and local governments have started to discuss counter measurement for possible seismic risks in the area taking account for what they learned from the Tohoku-oki event which is much larger than ever experienced in Japan Risk mitigation strategy for the next greater earthquake caused by the Philippine Sea plate (PSP) subducting beneath the Tokyo metropolitan area is of major concern because it caused past mega-thrust earthquakes, such as the 1703 Genroku earthquake (M8.0) and the 1923 Kanto earthquake (M7.9). An M7 or greater (M7+) earthquake in this area at present has high potential to produce devastating loss of life and property with even greater global economic repercussions. The Central Disaster Management Council of Japan estimates that an M7+ earthquake will cause 11,000 fatalities and 112 trillion yen (about 1 trillion US$) economic loss. In order to mitigate disaster for greater Tokyo, the Special Project for Earthquake Disaster Mitigation in the Tokyo Metropolitan Area was launched in collaboration with scientists, engineers, and social-scientists in nationwide institutions. We will discuss the main results that are obtained in the respective fields which have been integrated to improve information on the strategy assessment for seismic risk mitigation in the Tokyo metropolitan area; the project has been much improved after the Tohoku event. In order to image seismic structure beneath the Metropolitan Tokyo area we have developed Metropolitan Seismic Observation network (MeSO-net; Hirata et al., 2009). We have installed 296 seismic stations every few km (Kasahara et al., 2011). We conducted seismic

  15. Impact of the Great East Japan Earthquake on Hotel Industry in Pacific Tohoku Prefectures ---From Spatio-Temporal Dependence of Hotel Availability---

    Science.gov (United States)

    Sato, A.

    This paper investigates the impact of the Great Japan Earthquake(and subsequent tsunami turmoil) on socio-economic activities by using data on hotel opportunities collected from an electronic hotel booking service. A method to estimate both primary and secondary regional effects of a natural disaster on human behavior is proposed. It is confirmed that temporal variation in the regional share of available hotels before and after a natural disaster may be an indicator to measure the socio-economic impact at each district.

  16. The SARVIEWS Project: Automated SAR Processing in Support of Operational Near Real-time Volcano Monitoring

    Science.gov (United States)

    Meyer, F. J.; Webley, P. W.; Dehn, J.; Arko, S. A.; McAlpin, D. B.; Gong, W.

    2016-12-01

    Volcanic eruptions are among the most significant hazards to human society, capable of triggering natural disasters on regional to global scales. In the last decade, remote sensing has become established in operational volcano monitoring. Centers like the Alaska Volcano Observatory rely heavily on remote sensing data from optical and thermal sensors to provide time-critical hazard information. Despite this high use of remote sensing data, the presence of clouds and a dependence on solar illumination often limit their impact on decision making. Synthetic Aperture Radar (SAR) systems are widely considered superior to optical sensors in operational monitoring situations, due to their weather and illumination independence. Still, the contribution of SAR to operational volcano monitoring has been limited in the past due to high data costs, long processing times, and low temporal sampling rates of most SAR systems. In this study, we introduce the automatic SAR processing system SARVIEWS, whose advanced data analysis and data integration techniques allow, for the first time, a meaningful integration of SAR into operational monitoring systems. We will introduce the SARVIEWS database interface that allows for automatic, rapid, and seamless access to the data holdings of the Alaska Satellite Facility. We will also present a set of processing techniques designed to automatically generate a set of SAR-based hazard products (e.g. change detection maps, interferograms, geocoded images). The techniques take advantage of modern signal processing and radiometric normalization schemes, enabling the combination of data from different geometries. Finally, we will show how SAR-based hazard information is integrated in existing multi-sensor decision support tools to enable joint hazard analysis with data from optical and thermal sensors. We will showcase the SAR processing system using a set of recent natural disasters (both earthquakes and volcanic eruptions) to demonstrate its

  17. Environmental monitoring of El Hierro Island submarine volcano, by combining low and high resolution satellite imagery

    Science.gov (United States)

    Eugenio, F.; Martin, J.; Marcello, J.; Fraile-Nuez, E.

    2014-06-01

    El Hierro Island, located at the Canary Islands Archipelago in the Atlantic coast of North Africa, has been rocked by thousands of tremors and earthquakes since July 2011. Finally, an underwater volcanic eruption started 300 m below sea level on October 10, 2011. Since then, regular multidisciplinary monitoring has been carried out in order to quantify the environmental impacts caused by the submarine eruption. Thanks to this natural tracer release, multisensorial satellite imagery obtained from MODIS and MERIS sensors have been processed to monitor the volcano activity and to provide information on the concentration of biological, chemical and physical marine parameters. Specifically, low resolution satellite estimations of optimal diffuse attenuation coefficient (Kd) and chlorophyll-a (Chl-a) concentration under these abnormal conditions have been assessed. These remote sensing data have played a fundamental role during field campaigns guiding the oceanographic vessel to the appropriate sampling areas. In addition, to analyze El Hierro submarine volcano area, WorldView-2 high resolution satellite spectral bands were atmospherically and deglinted processed prior to obtain a high-resolution optimal diffuse attenuation coefficient model. This novel algorithm was developed using a matchup data set with MERIS and MODIS data, in situ transmittances measurements and a seawater radiative transfer model. Multisensor and multitemporal imagery processed from satellite remote sensing sensors have demonstrated to be a powerful tool for monitoring the submarine volcanic activities, such as discolored seawater, floating material and volcanic plume, having shown the capabilities to improve the understanding of submarine volcanic processes.

  18. Hawaii's volcanoes revealed

    Science.gov (United States)

    Eakins, Barry W.; Robinson, Joel E.; Kanamatsu, Toshiya; Naka, Jiro; Smith, John R.; Takahashi, Eiichi; Clague, David A.

    2003-01-01

    Hawaiian volcanoes typically evolve in four stages as volcanism waxes and wanes: (1) early alkalic, when volcanism originates on the deep sea floor; (2) shield, when roughly 95 percent of a volcano's volume is emplaced; (3) post-shield alkalic, when small-volume eruptions build scattered cones that thinly cap the shield-stage lavas; and (4) rejuvenated, when lavas of distinct chemistry erupt following a lengthy period of erosion and volcanic quiescence. During the early alkalic and shield stages, two or more elongate rift zones may develop as flanks of the volcano separate. Mantle-derived magma rises through a vertical conduit and is temporarily stored in a shallow summit reservoir from which magma may erupt within the summit region or be injected laterally into the rift zones. The ongoing activity at Kilauea's Pu?u ?O?o cone that began in January 1983 is one such rift-zone eruption. The rift zones commonly extend deep underwater, producing submarine eruptions of bulbous pillow lava. Once a volcano has grown above sea level, subaerial eruptions produce lava flows of jagged, clinkery ?a?a or smooth, ropy pahoehoe. If the flows reach the ocean they are rapidly quenched by seawater and shatter, producing a steep blanket of unstable volcanic sediment that mantles the upper submarine slopes. Above sea level then, the volcanoes develop the classic shield profile of gentle lava-flow slopes, whereas below sea level slopes are substantially steeper. While the volcanoes grow rapidly during the shield stage, they may also collapse catastrophically, generating giant landslides and tsunami, or fail more gradually, forming slumps. Deformation and seismicity along Kilauea's south flank indicate that slumping is occurring there today. Loading of the underlying Pacific Plate by the growing volcanic edifices causes subsidence, forming deep basins at the base of the volcanoes. Once volcanism wanes and lava flows no longer reach the ocean, the volcano continues to submerge, while

  19. Earthquake hazard assessment and small earthquakes

    International Nuclear Information System (INIS)

    Reiter, L.

    1987-01-01

    The significance of small earthquakes and their treatment in nuclear power plant seismic hazard assessment is an issue which has received increased attention over the past few years. In probabilistic studies, sensitivity studies showed that the choice of the lower bound magnitude used in hazard calculations can have a larger than expected effect on the calculated hazard. Of particular interest is the fact that some of the difference in seismic hazard calculations between the Lawrence Livermore National Laboratory (LLNL) and Electric Power Research Institute (EPRI) studies can be attributed to this choice. The LLNL study assumed a lower bound magnitude of 3.75 while the EPRI study assumed a lower bound magnitude of 5.0. The magnitudes used were assumed to be body wave magnitudes or their equivalents. In deterministic studies recent ground motion recordings of small to moderate earthquakes at or near nuclear power plants have shown that the high frequencies of design response spectra may be exceeded. These exceedances became important issues in the licensing of the Summer and Perry nuclear power plants. At various times in the past particular concerns have been raised with respect to the hazard and damage potential of small to moderate earthquakes occurring at very shallow depths. In this paper a closer look is taken at these issues. Emphasis is given to the impact of lower bound magnitude on probabilistic hazard calculations and the historical record of damage from small to moderate earthquakes. Limited recommendations are made as to how these issues should be viewed

  20. Cataloging tremor at Kilauea Volcano, Hawaii

    Science.gov (United States)

    Thelen, W. A.; Wech, A.

    2013-12-01

    Tremor is a ubiquitous seismic feature on Kilauea volcano, which emanates from at least three distinct sources. At depth, intermittent tremor and earthquakes thought to be associated with the underlying plumbing system of Kilauea (Aki and Koyanagi, 1981) occurs approximately 40 km below and 40 km SW of the summit. At the summit of the volcano, nearly continuous tremor is recorded close to a persistently degassing lava lake, which has been present since 2008. Much of this tremor is correlated with spattering at the lake surface, but tremor also occurs in the absence of spattering, and was observed at the summit of the volcano prior to the appearance of the lava lake, predominately in association with inflation/deflation events. The third known source of tremor is in the area of Pu`u `O`o, a vent that has been active since 1983. The exact source location and depth is poorly constrained for each of these sources. Consistently tracking the occurrence and location of tremor in these areas through time will improve our understanding of the plumbing geometry beneath Kilauea volcano and help identify precursory patterns in tremor leading to changes in eruptive activity. The continuous and emergent nature of tremor precludes the use of traditional earthquake techniques for automatic detection and location of seismicity. We implement the method of Wech and Creager (2008) to both detect and localize tremor seismicity in the three regions described above. The technique uses an envelope cross-correlation method in 5-minute windows that maximizes tremor signal coherency among seismic stations. The catalog is currently being built in near-realtime, with plans to extend the analysis to the past as time and continuous data availability permits. This automated detection and localization method has relatively poor depth constraints due to the construction of the envelope function. Nevertheless, the epicenters distinguish activity among the different source regions and serve as

  1. Sense of Community and Depressive Symptoms among Older Earthquake Survivors Following the 2008 Earthquake in Chengdu China

    Science.gov (United States)

    Li, Yawen; Sun, Fei; He, Xusong; Chan, Kin Sun

    2011-01-01

    This study examined the impact of an earthquake as well as the role of sense of community as a protective factor against depressive symptoms among older Chinese adults who survived an 8.0 magnitude earthquake in 2008. A household survey of a random sample was conducted 3 months after the earthquake and 298 older earthquake survivors participated…

  2. The problem about the possibility of establishing an interrelation between the activity of the sun and that of mud volcanos

    Energy Technology Data Exchange (ETDEWEB)

    Mekhtiyev, Sh.F.; Khalilov, E.N.

    1984-01-01

    Studies of the mud volcanos of Eastern Azerbaydzhan showed that periods of weakening in the mud volcano activity correspond to periods of increased solar activity and the opposite. A graph which characterizes the change in the mud volcano activity in time is built to establish the association between solar activity and the activity of the mud volcanos. Data from 300 eruptions of mud volcanos of the world were used. All the world's mud volcanos are located in zones of high seismic activity. These zones are characterized by the presence of deeply focused (subcrust) earthquakes. All the mud volcanos are located along seismic strips of the earth, which reflect zones of subduction or the Zavaritskiy Benioff zones. The mud volcanos are associated with global geodynamic processes, while their activity characterizes the activity of the subduction zones. The activity of the subduction zones rises in periods of increased solar activity. Building a rectilinear trend of the Gauss capacity showed that the activation of the world's mud volcanos is increased in time at a speed of 0.02 eruptions per year. The activation of the subduction zones also rises in time. These studies are one of the first attempts to analyze data about the eruptions of the world's mud volcanos with consideration of the new global tectonics and certain cosmic processes.

  3. [Earthquakes in El Salvador].

    Science.gov (United States)

    de Ville de Goyet, C

    2001-02-01

    The Pan American Health Organization (PAHO) has 25 years of experience dealing with major natural disasters. This piece provides a preliminary review of the events taking place in the weeks following the major earthquakes in El Salvador on 13 January and 13 February 2001. It also describes the lessons that have been learned over the last 25 years and the impact that the El Salvador earthquakes and other disasters have had on the health of the affected populations. Topics covered include mass-casualties management, communicable diseases, water supply, managing donations and international assistance, damages to the health-facilities infrastructure, mental health, and PAHO's role in disasters.

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

    Science.gov (United States)

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

    2012-12-01

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

  5. Anatomy of a volcano

    NARCIS (Netherlands)

    Hooper, A.; Wassink, J.

    2011-01-01

    The Icelandic volcano Eyjafjallajökull caused major disruption in European airspace last year. According to his co-author, Freysteinn Sigmundsson, the reconstruction published in Nature six months later by aerospace engineering researcher, Dr Andy Hooper, opens up a new direction in volcanology. “We

  6. Spying on volcanoes

    Science.gov (United States)

    Watson, Matthew

    2017-07-01

    Active volcanoes can be incredibly dangerous, especially to those who live nearby, but how do you get close enough to observe one in action? Matthew Watson explains how artificial drones are providing volcanologists with insights that could one day save human lives

  7. The recent seismicity of Teide volcano, Tenerife (Canary Islands, Spain)

    Science.gov (United States)

    D'Auria, L.; Albert, G. W.; Calvert, M. M.; Gray, A.; Vidic, C.; Barrancos, J.; Padilla, G.; García-Hernández, R.; Perez, N. M.

    2017-12-01

    Tenerife is an active volcanic island which experienced several eruptions of moderate intensity in historical times, and few explosive eruptions in the Holocene. The increasing population density and the consistent number of tourists are constantly raising the volcanic risk of the island.On 02/10/2016 a remarkable swarm of long-period events was recorded and was interpreted as the effect of a transient massive fluid discharge episode occurring within the deep hydrothermal system of Teide volcano. Actually, since Oct. 2016, the hydrothermal system of the volcano underwent a progressive pressurization, testified by the marked variation of different geochemical parameters. The most striking observation is the increase in the diffuse CO2 emission from the summit crater of Teide volcano which started increasing from a background value of about 20 tons/day and reaching a peak of 175 tons/day in Feb. 2017.The pressurization process has been accompanied by an increase in the volcano-tectonic seismicity of. Teide volcano, recorded by the Red Sísmica Canaria, managed by Instituto Volcanológico de Canarias (INVOLCAN). The network began its full operativity in Nov. 2016 and currently consists of 15 broadband seismic stations. Since Nov. 2016 the network detected more than 100 small magnitude earthquakes, located beneath Teide volcano at depths usually ranging between 5 and 15 km. On January 6th 2017 a M=2.5 earthquake was recorded in the area, being one of the strongest ever recorded since decades. Most of the events show typical features of the microseismicity of hydrothermal systems: high spatial and temporal clustering and similar waveforms of individual events which often are overlapped.We present the spatial and temporal distribution of the seismicity of Teide volcano since Nov. 2016, comparing it also with the past seismicity of the volcano. Furthermore we analyze the statistical properties of the numerous swarms recorded until now with the aid of a template

  8. Health impact of the 2004 Andaman Nicobar earthquake and tsunami in Indonesia.

    Science.gov (United States)

    Guha-Sapir, Debarati; van Panhuis, Willem Gijsbert

    2009-01-01

    The human impact of the tsunami that occurred on 26 December 2004 was enormous, with Indonesia bearing a huge proportion of the losses. The aftermath brought predictions of communicable disease outbreaks and widespread fear of epidemics. However, evidence from previous disasters due to natural hazards does not support all of these predictions. The objectives of this study were to: (1) describe the relative importance of infectious diseases and injuries as a consequence of a disaster due to natural hazards; and (2) identify key recommendations for the improvement of control and surveillance of these diseases during and after disasters. A team from the Center for Research on the Epidemiology of Disasters visited Jakarta and Banda Aceh from 11-23 January 2005, and collected data from the Central and Provincial Ministries of Health (MOH), the World Health Organization (WHO), and a field hospital from the International Committee of the Red Cross in Banda Aceh. The epidemiological profiles of diseases before and after the tsunami were compared. Cholera, tetanus, wounds and wound infections, acute respiratory infections, malaria, and dengue were included in this analysis. Certain diseases (e.g., cholera, malaria, dengue) are not always an immediate priority post-disaster. Rates of disaster-related health conditions requiring emergency response fell by half, and became negligible around four weeks after the precipitating events. Some conditions, such as aspiration pneumonia and tetanus, which normally are rare, require special preparedness for emergency personnel. In addition, resistant and rare pathogens are associated with disasters due to natural hazards in the tropics and require specialized knowledge for the rapid and successful treatment of related infections. Within the first four weeks of a disaster, international humanitarian agencies in the health sector should start working with the MOH. The WHO surveillance system established immediately after the tsunami

  9. Earthquake predictions using seismic velocity ratios

    Science.gov (United States)

    Sherburne, R. W.

    1979-01-01

    Since the beginning of modern seismology, seismologists have contemplated predicting earthquakes. The usefulness of earthquake predictions to the reduction of human and economic losses and the value of long-range earthquake prediction to planning is obvious. Not as clear are the long-range economic and social impacts of earthquake prediction to a speicifc area. The general consensus of opinion among scientists and government officials, however, is that the quest of earthquake prediction is a worthwhile goal and should be prusued with a sense of urgency. 

  10. Global Earthquake and Volcanic Eruption Economic losses and costs from 1900-2014: 115 years of the CATDAT database - Trends, Normalisation and Visualisation

    Science.gov (United States)

    Daniell, James; Skapski, Jens-Udo; Vervaeck, Armand; Wenzel, Friedemann; Schaefer, Andreas

    2015-04-01

    Over the past 12 years, an in-depth database has been constructed for socio-economic losses from earthquakes and volcanoes. The effects of earthquakes and volcanic eruptions have been documented in many databases, however, many errors and incorrect details are often encountered. To combat this, the database was formed with socioeconomic checks of GDP, capital stock, population and other elements, as well as providing upper and lower bounds to each available event loss. The definition of economic losses within the CATDAT Damaging Earthquakes Database (Daniell et al., 2011a) as of v6.1 has now been redefined to provide three options of natural disaster loss pricing, including reconstruction cost, replacement cost and actual loss, in order to better define the impact of historical disasters. Similarly for volcanoes as for earthquakes, a reassessment has been undertaken looking at the historical net and gross capital stock and GDP at the time of the event, including the depreciated stock, in order to calculate the actual loss. A normalisation has then been undertaken using updated population, GDP and capital stock. The difference between depreciated and gross capital can be removed from the historical loss estimates which have been all calculated without taking depreciation of the building stock into account. The culmination of time series from 1900-2014 of net and gross capital stock, GDP, direct economic loss data, use of detailed studies of infrastructure age, and existing damage surveys, has allowed the first estimate of this nature. The death tolls in earthquakes from 1900-2014 are presented in various forms, showing around 2.32 million deaths due to earthquakes (with a range of 2.18 to 2.63 million) and around 59% due to masonry buildings and 28% from secondary effects. For the death tolls from the volcanic eruption database, 98000 deaths with a range from around 83000 to 107000 is seen from 1900-2014. The application of VSL life costing from death and injury

  11. Impact of earthquakes on agriculture during the Roman-Byzantine period from pollen records of the Dead Sea laminated sediment

    Science.gov (United States)

    Leroy, Suzanne A. G.; Marco, Shmuel; Bookman, Revital; Miller, Charlotte S.

    2010-03-01

    The Dead Sea region holds the archives of a complex relationship between an ever-changing nature and ancient civilisations. Regional pollen diagrams show a Roman-Byzantine period standing out in the recent millennia by its wetter climate that allowed intensive arboriculture. During that period, the Dead Sea formed laminites that display mostly a seasonal character. A multidisciplinary study focused on two earthquakes, 31 BC and AD 363, recorded as seismites in the Ze'elim gully A unit III which has been well dated by radiocarbon in a previous study. The sampling of the sediment was done at an annual resolution starting from a few years before and finishing a decade after each earthquake. A clear drop in agricultural indicators (especially Olea and cereals) is shown. These pollen indicators mostly reflect human activities in the Judean Hills and coastal oases. Agriculture was disturbed in large part of the rift valley where earthquake damage affected irrigation and access to the fields. It took 4 to 5 yr to resume agriculture to previous conditions. Earthquakes must be seen as contributors to factors damaging societies. If combined with other factors such as climatic aridification, disease epidemics and political upheaval, they may lead to civilisation collapse.

  12. Connecting slow earthquakes to huge earthquakes

    OpenAIRE

    Obara, Kazushige; Kato, Aitaro

    2016-01-01

    Slow earthquakes are characterized by a wide spectrum of fault slip behaviors and seismic radiation patterns that differ from those of traditional earthquakes. However, slow earthquakes and huge megathrust earthquakes can have common slip mechanisms and are located in neighboring regions of the seismogenic zone. The frequent occurrence of slow earthquakes may help to reveal the physics underlying megathrust events as useful analogs. Slow earthquakes may function as stress meters because of th...

  13. Multi-parametric investigation of the volcano-hydrothermal system at Tatun Volcano Group, Northern Taiwan

    Science.gov (United States)

    Rontogianni, S.; Konstantinou, K. I.; Lin, C.-H.

    2012-07-01

    The Tatun Volcano Group (TVG) is located in northern Taiwan near the capital Taipei. In this study we selected and analyzed almost four years (2004-2007) of its seismic activity. The seismic network established around TVG initially consisted of eight three-component seismic stations with this number increasing to twelve by 2007. Local seismicity mainly involved high frequency (HF) earthquakes occurring as isolated events or as part of spasmodic bursts. Mixed and low frequency (LF) events were observed during the same period but more rarely. During the analysis we estimated duration magnitudes for the HF earthquakes and used a probabilistic non-linear method to accurately locate all these events. The complex frequencies of LF events were also analyzed with the Sompi method indicating fluid compositions consistent with a misty or dusty gas. We juxtaposed these results with geochemical/temperature anomalies extracted from fumarole gas and rainfall levels covering a similar period. This comparison is interpreted in the context of a model proposed earlier for the volcano-hydrothermal system of TVG where fluids and magmatic gases ascend from a magma body that lies at around 7-8 km depth. Most HF earthquakes occur as a response to stresses induced by fluid circulation within a dense network of cracks pervading the upper crust at TVG. The largest (ML ~ 3.1) HF event that occurred on 24 April 2006 at a depth of 5-6 km had source characteristics compatible with that of a tensile crack. It was followed by an enrichment in magmatic components of the fumarole gases as well as a fumarole temperature increase, and provides evidence for ascending fluids from a magma body into the shallow hydrothermal system. This detailed analysis and previous physical volcanology observations at TVG suggest that the region is volcanically active and that measures to mitigate potential hazards have to be considered by the local authorities.

  14. Multi-parametric investigation of the volcano-hydrothermal system at Tatun Volcano Group, Northern Taiwan

    Directory of Open Access Journals (Sweden)

    S. Rontogianni

    2012-07-01

    Full Text Available The Tatun Volcano Group (TVG is located in northern Taiwan near the capital Taipei. In this study we selected and analyzed almost four years (2004–2007 of its seismic activity. The seismic network established around TVG initially consisted of eight three-component seismic stations with this number increasing to twelve by 2007. Local seismicity mainly involved high frequency (HF earthquakes occurring as isolated events or as part of spasmodic bursts. Mixed and low frequency (LF events were observed during the same period but more rarely. During the analysis we estimated duration magnitudes for the HF earthquakes and used a probabilistic non-linear method to accurately locate all these events. The complex frequencies of LF events were also analyzed with the Sompi method indicating fluid compositions consistent with a misty or dusty gas. We juxtaposed these results with geochemical/temperature anomalies extracted from fumarole gas and rainfall levels covering a similar period. This comparison is interpreted in the context of a model proposed earlier for the volcano-hydrothermal system of TVG where fluids and magmatic gases ascend from a magma body that lies at around 7–8 km depth. Most HF earthquakes occur as a response to stresses induced by fluid circulation within a dense network of cracks pervading the upper crust at TVG. The largest (ML ~ 3.1 HF event that occurred on 24 April 2006 at a depth of 5–6 km had source characteristics compatible with that of a tensile crack. It was followed by an enrichment in magmatic components of the fumarole gases as well as a fumarole temperature increase, and provides evidence for ascending fluids from a magma body into the shallow hydrothermal system. This detailed analysis and previous physical volcanology observations at TVG suggest that the region is volcanically active and that measures to mitigate potential hazards have to be considered by the local authorities.

  15. Intense Seismic Activity at Chiles and Cerro Negro Volcanoes on the Colombia-Ecuador Border

    Science.gov (United States)

    Torres, R. A.; Cadena, O.; Gomez, D.; Ruiz, M. C.; Prejean, S. G.; Lyons, J. J.; White, R. A.

    2015-12-01

    The region of Chiles and Cerro Negro volcanoes, located on the Colombian-Ecuadorian border, has experienced an ongoing seismic swarm beginning in Aug. 2013. Based on concern for local residents and authorities, a cooperative broadband monitoring network was installed by the Servicio Geológico Colombiano in Colombia and the Instituto Geofísico of the Escuela Politécnica Nacional in Ecuador. Since November 2013 more than 538,000 earthquakes were recorded; although since May 2015 the seismicity has decreased significantly to an average of 70 events per day. Three large earthquake swarms with increasing energy occurred in Aug.-Oct. 2013, March-May 2014, and Sept.-Dec. 2014. By the end of 2014, roughly 400 earthquakes greater than M 3 had occurred with a maximum rate of 8000 earthquakes per day. The largest earthquake was a 5.6 ML on Oct. 20, 2014. This event produced an InSAR coseismic deformation of ~23 cm (S. Ebmeier, personal communication). Most events are typical brittle failure volcano-tectonic (VT) earthquakes that are located in a cluster beneath the southern flank of Chiles volcano, with depths between 1.5 and 10 km. Although the great majority of earthquakes are VT, some low-frequency (LF, ~0.5 Hz) and very-low-frequency (VLF) events have occurred. Particle motion analysis suggests that the VLF source migrated with time. While a VLF on Oct. 15, 2014 was located south of Chiles volcano, near the InSAR source, the VLF registered on Feb. 14, 2015 was likely located very close to Chiles Volcano. We infer that magma intrusion and resulting fluid exsolution at depths greater than 5 km are driving seismicity in the Chiles-Cerro Negro region. However earthquakes are failing in a manner consistent with regional tectonics. Relative relocations reveal a structure consistent with mapped regional faults. Thus seismicity is likely controlled by an interaction of magmatic and tectonic processes. Because the regional stress field is highly compressional and the volcanoes

  16. The investigation of the impacts of major disasters, on the basis of the Van earthquake (October 23, 2011, Turkey), on the profile of the injuries due to occupational accidents.

    Science.gov (United States)

    Hekimoglu, Yavuz; Dursun, Recep; Karadas, Sevdegul; Asirdizer, Mahmut

    2015-10-01

    The purpose of this study is to identify the impacts of major disasters, on the basis of the Van earthquake (October 23, 2011, Turkey), on the profile of the injuries due to occupational accidents. In this study, we evaluated 245 patients of occupational accidents who were admitted to emergency services of Van city hospitals in the 1-year periods including pre-earthquake and post-earthquake. We determined that there was a 63.4% (P accidents in the post-earthquake period compared to the pre-earthquake period. Also, injuries due to occupational accidents increased 211% (P accidents. In this study, the impact of disasters such as earthquakes on the accidents at work was evaluated as we have not seen in literature. This study emphasizes that governments should make regulations and process relating to the post-disaster business before the emergence of disaster by taking into account factors that may increase their work-related accidents. Copyright © 2015 Elsevier Ltd and Faculty of Forensic and Legal Medicine. All rights reserved.

  17. Earthquakes, detecting and understanding them

    International Nuclear Information System (INIS)

    2008-05-01

    The signatures at the surface of the Earth is continually changing on a geological timescale. The tectonic plates, which make up this surface, are moving in relation to each other. On human timescale, these movements are the result of earthquakes, which suddenly, release energy accumulated over a period of time. The vibrations they produce propagate through the interior of the Earth: these are seismic waves. However, other phenomena can generate seismic waves, such as volcanoes, quarry blasts, etc. The surf of the ocean waves on the coasts, the wind in the trees and human activity (industry and road traffic) all contribute to the 'seismic background noise'. Sensors are able to detect signals from events which are then discriminated, analyzed and located. Earthquakes and active volcanoes are not distributed randomly over the surface of the globe: they mainly coincide with mountain chains and ocean trenches and ridges. 'An earthquake results from the abrupt release of the energy accumulated by movements and rubbing of different plates'. The study of the propagation of seismic waves has allowed to determine the outline of the plates inside the Earth and has highlighted their movements. There are seven major plates which are colliding, diverging or sliding past each other. Each year the continents move several centimeters with respect to one another. This process, known as 'continental drift', was finally explained by plate tectonics. The initial hypothesis for this science dates from the beginning of the 20. century, but it was not confirmed until the 1960's. It explains that convection inside the Earth is the source of the forces required for these movements. This science, as well as explaining these great movements, has provided a coherent, unifying and quantitative framework, which unites the explanations for all the geophysical phenomena under one mechanism. (authors)

  18. Catalogue of Icelandic Volcanoes

    Science.gov (United States)

    Ilyinskaya, Evgenia; Larsen, Gudrún; Gudmundsson, Magnús T.; Vogfjörd, Kristin; Jonsson, Trausti; Oddsson, Björn; Reynisson, Vidir; Pagneux, Emmanuel; Barsotti, Sara; Karlsdóttir, Sigrún; Bergsveinsson, Sölvi; Oddsdóttir, Thorarna

    2017-04-01

    The Catalogue of Icelandic Volcanoes (CIV) is a newly developed open-access web resource (http://icelandicvolcanoes.is) intended to serve as an official source of information about volcanoes in Iceland for the public and decision makers. CIV contains text and graphic information on all 32 active volcanic systems in Iceland, as well as real-time data from monitoring systems in a format that enables non-specialists to understand the volcanic activity status. The CIV data portal contains scientific data on all eruptions since Eyjafjallajökull 2010 and is an unprecedented endeavour in making volcanological data open and easy to access. CIV forms a part of an integrated volcanic risk assessment project in Iceland GOSVÁ (commenced in 2012), as well as being part of the European Union funded effort FUTUREVOLC (2012-2016) on establishing an Icelandic volcano supersite. The supersite concept implies integration of space and ground based observations for improved monitoring and evaluation of volcanic hazards, and open data policy. This work is a collaboration of the Icelandic Meteorological Office, the Institute of Earth Sciences at the University of Iceland, and the Civil Protection Department of the National Commissioner of the Iceland Police, with contributions from a large number of specialists in Iceland and elsewhere.

  19. Earthquake evaluation of a substation network

    International Nuclear Information System (INIS)

    Matsuda, E.N.; Savage, W.U.; Williams, K.K.; Laguens, G.C.

    1991-01-01

    The impact of the occurrence of a large, damaging earthquake on a regional electric power system is a function of the geographical distribution of strong shaking, the vulnerability of various types of electric equipment located within the affected region, and operational resources available to maintain or restore electric system functionality. Experience from numerous worldwide earthquake occurrences has shown that seismic damage to high-voltage substation equipment is typically the reason for post-earthquake loss of electric service. In this paper, the authors develop and apply a methodology to analyze earthquake impacts on Pacific Gas and Electric Company's (PG and E's) high-voltage electric substation network in central and northern California. The authors' objectives are to identify and prioritize ways to reduce the potential impact of future earthquakes on our electric system, refine PG and E's earthquake preparedness and response plans to be more realistic, and optimize seismic criteria for future equipment purchases for the electric system

  20. False Color Image of Volcano Sapas Mons

    Science.gov (United States)

    1991-01-01

    This false-color image shows the volcano Sapas Mons, which is located in the broad equatorial rise called Atla Regio (8 degrees north latitude and 188 degrees east longitude). The area shown is approximately 650 kilometers (404 miles) on a side. Sapas Mons measures about 400 kilometers (248 miles) across and 1.5 kilometers (0.9 mile) high. Its flanks show numerous overlapping lava flows. The dark flows on the lower right are thought to be smoother than the brighter ones near the central part of the volcano. Many of the flows appear to have been erupted along the flanks of the volcano rather than from the summit. This type of flank eruption is common on large volcanoes on Earth, such as the Hawaiian volcanoes. The summit area has two flat-topped mesas, whose smooth tops give a relatively dark appearance in the radar image. Also seen near the summit are groups of pits, some as large as one kilometer (0.6 mile) across. These are thought to have formed when underground chambers of magma were drained through other subsurface tubes and lead to a collapse at the surface. A 20 kilometer-diameter (12-mile diameter) impact crater northeast of the volcano is partially buried by the lava flows. Little was known about Atla Regio prior to Magellan. The new data, acquired in February 1991, show the region to be composed of at least five large volcanoes such as Sapas Mons, which are commonly linked by complex systems of fractures or rift zones. If comparable to similar features on Earth, Atla Regio probably formed when large volumes of molten rock upwelled from areas within the interior of Venus known as'hot spots.' Magellan is a NASA spacecraft mission to map the surface of Venus with imaging radar. The basic scientific instrument is a synthetic aperture radar, or SAR, which can look through the thick clouds perpetually shielding the surface of Venus. Magellan is in orbit around Venus which completes one turn around its axis in 243 Earth days. That period of time, one Venus day

  1. Seismic Activity at Vailulu'u, Samoa's Youngest Volcano

    Science.gov (United States)

    Konter, J.; Staudigel, H.; Hart, S.

    2002-12-01

    Submarine volcanic systems, as a product of the Earth's mantle, play an essential role in the Earth's heat budget and in the interaction between the solid Earth and the hydrosphere and biosphere. Their eruptive and intrusive activity exerts an important control on these hydrothermal systems. In March 2000, we deployed an array of five ocean bottom hydrophones (OBH) on the summit region (625-995 m water depth) of Vailulu'u Volcano (14°12.9'S;169°03.5'W); this volcano represents the active end of the Samoan hotspot chain and is one of only a few well-studied intra-plate submarine volcanoes. We monitored seismic activity for up to 12 months at low sample rate (25 Hz), and for shorter times at a higher sample rate (125 Hz). We have begun to catalogue and locate a variety of acoustic events from this network. Ambient ocean noise was filtered out by a 4th-order Butterworth bandpass filter (2.3 - 10 Hz). We distinguish small local earthquakes from teleseismic activity, mostly identified by T- (acoustic) waves, by comparison with a nearby GSN station (AFI). Most of the detected events are T-phases from teleseismic earthquakes, characterized by their emergent coda and high frequency content (up to 30 Hz); the latter distinguishes them from low frequency emergent signals associated with the volcano (e.g. tremor). A second type of event is characterized by impulsive arrivals, with coda lasting a few seconds. The differences in arrival times between stations on the volcano are too small for these events to be T-waves; they are very likely to be local events, since the GSN station in Western Samoa (AFI) shows no arrivals close in time to these events. Preliminary locations show that these small events occur approximately once per day and are located within the volcano (the 95% confidence ellipse is similar to the size of the volcano, due to the small size of the OBH network). Several events are located relatively close to each other (within a km radius) just NW of the crater.

  2. Monitoring eruption activity using temporal stress changes at Mount Ontake volcano.

    Science.gov (United States)

    Terakawa, Toshiko; Kato, Aitaro; Yamanaka, Yoshiko; Maeda, Yuta; Horikawa, Shinichiro; Matsuhiro, Kenjiro; Okuda, Takashi

    2016-02-19

    Volcanic activity is often accompanied by many small earthquakes. Earthquake focal mechanisms represent the fault orientation and slip direction, which are influenced by the stress field. Focal mechanisms of volcano-tectonic earthquakes provide information on the state of volcanoes via stresses. Here we demonstrate that quantitative evaluation of temporal stress changes beneath Mt. Ontake, Japan, using the misfit angles of focal mechanism solutions to the regional stress field, is effective for eruption monitoring. The moving average of misfit angles indicates that during the precursory period the local stress field beneath Mt. Ontake was deviated from the regional stress field, presumably by stress perturbations caused by the inflation of magmatic/hydrothermal fluids, which was removed immediately after the expulsion of volcanic ejecta. The deviation of the local stress field can be an indicator of increases in volcanic activity. The proposed method may contribute to the mitigation of volcanic hazards.

  3. The CATDAT damaging earthquakes database

    Directory of Open Access Journals (Sweden)

    J. E. Daniell

    2011-08-01

    Full Text Available The global CATDAT damaging earthquakes and secondary effects (tsunami, fire, landslides, liquefaction and fault rupture database was developed to validate, remove discrepancies, and expand greatly upon existing global databases; and to better understand the trends in vulnerability, exposure, and possible future impacts of such historic earthquakes.

    Lack of consistency and errors in other earthquake loss databases frequently cited and used in analyses was a major shortcoming in the view of the authors which needed to be improved upon.

    Over 17 000 sources of information have been utilised, primarily in the last few years, to present data from over 12 200 damaging earthquakes historically, with over 7000 earthquakes since 1900 examined and validated before insertion into the database. Each validated earthquake includes seismological information, building damage, ranges of social losses to account for varying sources (deaths, injuries, homeless, and affected, and economic losses (direct, indirect, aid, and insured.

    Globally, a slightly increasing trend in economic damage due to earthquakes is not consistent with the greatly increasing exposure. The 1923 Great Kanto ($214 billion USD damage; 2011 HNDECI-adjusted dollars compared to the 2011 Tohoku (>$300 billion USD at time of writing, 2008 Sichuan and 1995 Kobe earthquakes show the increasing concern for economic loss in urban areas as the trend should be expected to increase. Many economic and social loss values not reported in existing databases have been collected. Historical GDP (Gross Domestic Product, exchange rate, wage information, population, HDI (Human Development Index, and insurance information have been collected globally to form comparisons.

    This catalogue is the largest known cross-checked global historic damaging earthquake database and should have far-reaching consequences for earthquake loss estimation, socio-economic analysis, and the global

  4. The CATDAT damaging earthquakes database

    Science.gov (United States)

    Daniell, J. E.; Khazai, B.; Wenzel, F.; Vervaeck, A.

    2011-08-01

    The global CATDAT damaging earthquakes and secondary effects (tsunami, fire, landslides, liquefaction and fault rupture) database was developed to validate, remove discrepancies, and expand greatly upon existing global databases; and to better understand the trends in vulnerability, exposure, and possible future impacts of such historic earthquakes. Lack of consistency and errors in other earthquake loss databases frequently cited and used in analyses was a major shortcoming in the view of the authors which needed to be improved upon. Over 17 000 sources of information have been utilised, primarily in the last few years, to present data from over 12 200 damaging earthquakes historically, with over 7000 earthquakes since 1900 examined and validated before insertion into the database. Each validated earthquake includes seismological information, building damage, ranges of social losses to account for varying sources (deaths, injuries, homeless, and affected), and economic losses (direct, indirect, aid, and insured). Globally, a slightly increasing trend in economic damage due to earthquakes is not consistent with the greatly increasing exposure. The 1923 Great Kanto (214 billion USD damage; 2011 HNDECI-adjusted dollars) compared to the 2011 Tohoku (>300 billion USD at time of writing), 2008 Sichuan and 1995 Kobe earthquakes show the increasing concern for economic loss in urban areas as the trend should be expected to increase. Many economic and social loss values not reported in existing databases have been collected. Historical GDP (Gross Domestic Product), exchange rate, wage information, population, HDI (Human Development Index), and insurance information have been collected globally to form comparisons. This catalogue is the largest known cross-checked global historic damaging earthquake database and should have far-reaching consequences for earthquake loss estimation, socio-economic analysis, and the global reinsurance field.

  5. Seismic instrumentation plan for the Hawaiian Volcano Observatory

    Science.gov (United States)

    Thelen, Weston A.

    2014-01-01

    The seismic network operated by the U.S. Geological Survey’s Hawaiian Volcano Observatory (HVO) is the main source of authoritative data for reporting earthquakes in the State of Hawaii, including those that occur on the State’s six active volcanoes (Kīlauea, Mauna Loa, Hualālai, Mauna Kea, Haleakalā, Lō‘ihi). Of these volcanoes, Kīlauea and Mauna Loa are considered “very high threat” in a report on the rationale for a National Volcanic Early Warning System (NVEWS) (Ewert and others, 2005). This seismic instrumentation plan assesses the current state of HVO’s seismic network with respect to the State’s active volcanoes and calculates the number of stations that are needed to upgrade the current network to provide a seismic early warning capability for forecasting volcanic activity. Further, the report provides proposed priorities for upgrading the seismic network and a cost assessment for both the installation costs and maintenance costs of the improved network that are required to fully realize the potential of the early warning system.

  6. The impact of earthquakes on the city of Aigio in Greece. Urban planning as a factor in mitigating seismic damage

    International Nuclear Information System (INIS)

    Athanasopoulou, Evanthia; Despoiniadou, Varvara; Dritsos, Stefanos

    2008-01-01

    This paper examines the effects of the mortal earthquake on the city of Aigio in Greece in 1995, with particular focus on urbanization and planning policies. It is based on interviews with experts and surveys on damage to buildings following this earthquake. The analysis takes into account several factors, such as exact location, land use, construction period and the height of damaged buildings. Furthermore, the relationship between the seismic damage and the postseismic construction development of Aigio is examined and the conclusion is reached that the Greek urban planning system needs to be better organized to prepare for seismic damage. To this end, the paper recommends a five-point discussion agenda for applying local planning to seismic mitigation

  7. The impact of earthquakes on the city of Aigio in Greece. Urban planning as a factor in mitigating seismic damage.

    Science.gov (United States)

    Athanasopoulou, Evanthia; Despoiniadou, Varvara; Dritsos, Stefanos

    2008-07-01

    This paper examines the effects of the mortal earthquake on the city of Aigio in Greece in 1995, with particular focus on urbanization and planning policies. It is based on interviews with experts and surveys on damage to buildings following this earthquake. The analysis takes into account several factors, such as exact location, land use, construction period and the height of damaged buildings. Furthermore, the relationship between the seismic damage and the postseismic construction development of Aigio is examined and the conclusion is reached that the Greek urban planning system needs to be better organized to prepare for seismic damage. To this end, the paper recommends a five-point discussion agenda for applying local planning to seismic mitigation.

  8. Long-term impacts of tropical storms and earthquakes on human population growth in Haiti and the Dominican Republic

    OpenAIRE

    Christian D. Klose; Christian Webersik

    2011-01-01

    Since the 18th century, Haiti and the Dominican Republic have experienced similar natural forces, including earthquakes and tropical storms. These countries are two of the most prone of all Latin American and Caribbean countries to natural hazards events, while Haiti seems to be more vulnerable to natural forces. This article discusses to what extent geohazards have shaped both nation's demographic developments. The data show that neither atmospheric nor seismic forces that directly hit ...

  9. Long-term impacts of tropical storms and earthquakes on human population growth in Haiti and Dominican Republic

    OpenAIRE

    Christian D. Klose; Christian Webersik

    2010-01-01

    The two Caribbean states, Haiti and the Dominican Republic, have experienced similar natural forces since the 18th century, including hurricanes and earthquakes. Although, both countries seem to be two of the most prone of all Latin American and Caribbean countries to natural hazard events, historically, Haiti tends to be more vulnerable to natural forces. The purpose of this article is to understand to what extent geohazards shape demographic changes. Research findings of this study show tha...

  10. Impact of sea-level rise on earthquake and landslide triggering offshore the Alentejo margin (SW Iberia)

    Science.gov (United States)

    Neves, M. C.; Roque, C.; Luttrell, K. M.; Vázquez, J. T.; Alonso, B.

    2016-12-01

    Earthquakes and submarine landslides are recurrent and widespread manifestations of fault activity offshore SW Iberia. The present work tests the effects of sea-level rise on offshore fault systems using Coulomb stress change calculations across the Alentejo margin. Large-scale faults capable of generating large earthquakes and tsunamis in the region, especially NE-SW trending thrusts and WNW-ESE trending dextral strike-slip faults imaged at basement depths, are either blocked or unaffected by flexural effects related to sea-level changes. Large-magnitude earthquakes occurring along these structures may, therefore, be less frequent during periods of sea-level rise. In contrast, sea-level rise promotes shallow fault ruptures within the sedimentary sequence along the continental slope and upper rise within distances of failures may either increase (if triggered by shallow fault ruptures) or decrease (if triggered by deep fault ruptures) as a result of sea-level rise. Moreover, observations of slope failures affecting the area of the Sines contourite drift highlight the role of sediment properties as preconditioning factors in this region.

  11. Earthquake Facts

    Science.gov (United States)

    ... North Dakota, and Wisconsin. The core of the earth was the first internal structural element to be identified. In 1906 R.D. Oldham discovered it from his studies of earthquake records. The inner core is solid, and the outer core is liquid and so does not transmit ...

  12. Understanding Earthquakes

    Science.gov (United States)

    Davis, Amanda; Gray, Ron

    2018-01-01

    December 26, 2004 was one of the deadliest days in modern history, when a 9.3 magnitude earthquake--the third largest ever recorded--struck off the coast of Sumatra in Indonesia (National Centers for Environmental Information 2014). The massive quake lasted at least 10 minutes and devastated the Indian Ocean. The quake displaced an estimated…

  13. Earthquake location determination using data from DOMERAPI and BMKG seismic networks: A preliminary result of DOMERAPI project

    Energy Technology Data Exchange (ETDEWEB)

    Ramdhan, Mohamad [Study Program of Earth Science, Institut Teknologi Bandung, Jl. Ganesa 10, Bandung, 40132 (Indonesia); Agency for Meteorology, Climatology and Geophysics of Indonesia (BMKG) Jl. Angkasa 1 No. 2 Kemayoran, Jakarta Pusat, 10720 (Indonesia); Nugraha, Andri Dian; Widiyantoro, Sri [Global Geophysics Research Group, Faculty of Mining and Petroleum Engineering, Institut TeknologiBandung, Jl. Ganesa 10, Bandung, 40132 (Indonesia); Métaxian, Jean-Philippe [Institut de Recherche pour le Développement (IRD) (France); Valencia, Ayunda Aulia, E-mail: mohamad.ramdhan@bmkg.go.id [Study Program of Geophysical Engineering, Institut Teknologi Bandung, Jl. Ganesa 10, Bandung, 40132 (Indonesia)

    2015-04-24

    DOMERAPI project has been conducted to comprehensively study the internal structure of Merapi volcano, especially about deep structural features beneath the volcano. DOMERAPI earthquake monitoring network consists of 46 broad-band seismometers installed around the Merapi volcano. Earthquake hypocenter determination is a very important step for further studies, such as hypocenter relocation and seismic tomographic imaging. Ray paths from earthquake events occurring outside the Merapi region can be utilized to delineate the deep magma structure. Earthquakes occurring outside the DOMERAPI seismic network will produce an azimuthal gap greater than 180{sup 0}. Owing to this situation the stations from BMKG seismic network can be used jointly to minimize the azimuthal gap. We identified earthquake events manually and carefully, and then picked arrival times of P and S waves. The data from the DOMERAPI seismic network were combined with the BMKG data catalogue to determine earthquake events outside the Merapi region. For future work, we will also use the BPPTKG (Center for Research and Development of Geological Disaster Technology) data catalogue in order to study shallow structures beneath the Merapi volcano. The application of all data catalogues will provide good information as input for further advanced studies and volcano hazards mitigation.

  14. Geophysical Observations Supporting Research of Magmatic Processes at Icelandic Volcanoes

    Science.gov (United States)

    Vogfjörd, Kristín. S.; Hjaltadóttir, Sigurlaug; Roberts, Matthew J.

    2010-05-01

    Magmatic processes at volcanoes on the boundary between the European and North American plates in Iceland are observed with in-situ multidisciplinary geophysical networks owned by different national, European or American universities and research institutions, but through collaboration mostly operated by the Icelandic Meteorological Office. The terrestrial observations are augmented by space-based interferometric synthetic aperture radar (InSAR) images of the volcanoes and their surrounding surface. Together this infrastructure can monitor magma movements in several volcanoes from the base of the crust up to the surface. The national seismic network is sensitive enough to detect small scale seismicity deep in the crust under some of the voclanoes. High resolution mapping of this seismicity and its temporal progression has been used to delineate the track of the magma as it migrates upwards in the crust, either to form an intrusion at shallow levels or to reach the surface in an eruption. Broadband recording has also enabled capturing low frequency signals emanating from magmatic movements. In two volcanoes, Eyjafjallajökull and Katla, just east of the South Iceland Seismic Zone (SISZ), seismicity just above the crust-mantle boundary has revealed magma intruding into the crust from the mantle below. As the magma moves to shallower levels, the deformation of the Earth‘s surface is captured by geodetic systems, such as continuous GPS networks, (InSAR) images of the surface and -- even more sensitive to the deformation -- strain meters placed in boreholes around 200 m below the Earth‘s surface. Analysis of these signals can reveal the size and shape of the magma as well as the temporal evolution. At near-by Hekla volcano flanking the SISZ to the north, where only 50% of events are of M>1 compared to 86% of earthquakes in Eyjafjallajökull, the sensitivity of the seismic network is insufficient to detect the smallest seismicity and so the volcano appears less

  15. Ruiz Volcano: Preliminary report

    Science.gov (United States)

    Ruiz Volcano, Colombia (4.88°N, 75.32°W). All times are local (= GMT -5 hours).An explosive eruption on November 13, 1985, melted ice and snow in the summit area, generating lahars that flowed tens of kilometers down flank river valleys, killing more than 20,000 people. This is history's fourth largest single-eruption death toll, behind only Tambora in 1815 (92,000), Krakatau in 1883 (36,000), and Mount Pelée in May 1902 (28,000). The following briefly summarizes the very preliminary and inevitably conflicting information that had been received by press time.

  16. Magma plumbing system and seismicity of an active mid-ocean ridge volcano.

    Science.gov (United States)

    Schmid, Florian; Schlindwein, Vera; Koulakov, Ivan; Plötz, Aline; Scholz, John-Robert

    2017-02-20

    At mid-ocean ridges volcanism generally decreases with spreading rate but surprisingly massive volcanic centres occur at the slowest spreading ridges. These volcanoes can host unexpectedly strong earthquakes and vigorous, explosive submarine eruptions. Our understanding of the geodynamic processes forming these volcanic centres is still incomplete due to a lack of geophysical data and the difficulty to capture their rare phases of magmatic activity. We present a local earthquake tomographic image of the magma plumbing system beneath the Segment 8 volcano at the ultraslow-spreading Southwest Indian Ridge. The tomography shows a confined domain of partial melt under the volcano. We infer that from there melt is horizontally transported to a neighbouring ridge segment at 35 km distance where microearthquake swarms and intrusion tremor occur that suggest ongoing magmatic activity. Teleseismic earthquakes around the Segment 8 volcano, prior to our study, indicate that the current magmatic spreading episode may already have lasted over a decade and hence its temporal extent greatly exceeds the frequent short-lived spreading episodes at faster opening mid-ocean ridges.

  17. Frictional-faulting model for harmonic tremor before Redoubt Volcano eruptions

    Science.gov (United States)

    Dmitrieva, Ksenia; Hotovec-Ellis, Alicia J.; Prejean, Stephanie G.; Dunham, Eric M.

    2013-01-01

    Seismic unrest, indicative of subsurface magma transport and pressure changes within fluid-filled cracks and conduits, often precedes volcanic eruptions. An intriguing form of volcano seismicity is harmonic tremor, that is, sustained vibrations in the range of 0.5–5 Hz. Many source processes can generate harmonic tremor. Harmonic tremor in the 2009 eruption of Redoubt Volcano, Alaska, has been linked to repeating earthquakes of magnitudes around 0.5–1.5 that occur a few kilometres beneath the vent. Before many explosions in that eruption, these small earthquakes occurred in such rapid succession—up to 30 events per second—that distinct seismic wave arrivals blurred into continuous, high-frequency tremor. Tremor abruptly ceased about 30 s before the explosions. Here we introduce a frictional-faulting model to evaluate the credibility and implications of this tremor mechanism. We find that the fault stressing rates rise to values ten orders of magnitude higher than in typical tectonic settings. At that point, inertial effects stabilize fault sliding and the earthquakes cease. Our model of the Redoubt Volcano observations implies that the onset of volcanic explosions is preceded by active deformation and extreme stressing within a localized region of the volcano conduit, at a depth of several kilometres.

  18. Complex surface deformation of Akutan volcano, Alaska revealed from InSAR time series

    Science.gov (United States)

    Wang, Teng; DeGrandpre, Kimberly; Lu, Zhong; Freymueller, Jeffrey T.

    2018-02-01

    Akutan volcano is one of the most active volcanoes in the Aleutian arc. An intense swarm of volcano-tectonic earthquakes occurred across the island in 1996. Surface deformation after the 1996 earthquake sequence has been studied using Interferometric Synthetic Aperture Radar (InSAR), yet it is hard to determine the detailed temporal behavior and spatial extent of the deformation due to decorrelation and the sparse temporal sampling of SAR data. Atmospheric delay anomalies over Akutan volcano are also strong, bringing additional technical challenges. Here we present a time series InSAR analysis from 2003 to 2016 to reveal the surface deformation in more detail. Four tracks of Envisat data acquired from 2003 to 2010 and one track of TerraSAR-X data acquired from 2010 to 2016 are processed to produce high-resolution surface deformation, with a focus on studying two transient episodes of inflation in 2008 and 2014. For the TerraSAR-X data, the atmospheric delay is estimated and removed using the common-master stacking method. These derived deformation maps show a consistently uplifting area on the northeastern flank of the volcano. From the TerraSAR-X data, we quantify the velocity of the subsidence inside the caldera to be as high as 10 mm/year, and identify another subsidence area near the ground cracks created during the 1996 swarm.

  19. Emergence of Lava Dome from the Crater Lake of Kelud Volcano, East Java

    Directory of Open Access Journals (Sweden)

    Sri Hidayati

    2014-06-01

    Full Text Available DOI: 10.17014/ijog.v4i4.83Kelud Volcano (+1731 m in East Java is one of the most active and dangerous volcanoes in Indonesia. A large lake occupies the summit crater. Historical eruptions generally only lasted for a very short time, mostly no longer than a few hours. The outburst is usually accompanied by pyroclastic flows. On August 2007, the activity of the volcano was initiated by the increase of the temperature of lake water and the change of the colour from typical green to yellow. Activities of the volcano are discussed following the swarms of volcano-tectonic (VT earthquakes on September 10th, September 26th to 29th, and October 24th to November 2nd. On September 26th to 29th, hypocentral distribution of those VT shifted from 5 km deep to just beneath the crater. The highest number of VT earthquakes occurred on November 1st attaining 50 events, then followed by a swarm of B-type events, where the number reached 1437 events in a day. The volcanic activity peaked on November 3rd when seismic records became saturated, which then was preceded by a sharp increase of lake temperature and a sudden deflation of radial tilt. It suggests that the lava extrusion forming a lava dome was taking place.

  20. Assessing the Mental Health Impact of the 2011 Great Japan Earthquake, Tsunami, and Radiation Disaster on Elementary and Middle School Children in the Fukushima Prefecture of Japan.

    Science.gov (United States)

    Lieber, Mark

    2017-01-01

    On March 11, 2011, a magnitude 9.0 earthquake occurred off of Japan's Pacific coast, which was followed by huge tsunamis that destroyed many coastal cities in the area. Due to the earthquake and subsequent tsunami, malfunctions occurred at the Fukushima Daiichi (Fukushima I) nuclear power plant, resulting in the release of radioactive material in the region. While recent studies have investigated the effects of these events on the mental health of adults in the region, no studies have yet been performed investigating similar effects among children. This study aims to fill that gap by: 1) assessing the mental health of elementary and middle school children living within the Fukushima prefecture of Japan, and 2) identifying risk and protective factors that are associated with the children's mental health scores. These factors were quantified using an original demographics survey, the Strengths and Difficulties Questionnaire (SDQ), and the Impact of Event Scale-Revised (IES-R), the latter two of which have been previously validated in a Japanese setting. The surveys were distributed to approximately 3,650 elementary and middle school students during the months of February and March, 2012. The data suggests that those children who had been relocated to the city of Koriyama had significantly higher SDQ scores than those children who were native to Koriyama (p children affected by natural disasters, younger children and those with parents suffering from trauma-related distress are particularly vulnerable to the onset of pediatric mental disturbances.

  1. Impact of the Great East Japan Earthquake and tsunami on health, medical care and public health systems in Iwate Prefecture, Japan, 2011.

    Science.gov (United States)

    Nohara, Masaru

    2011-10-01

    The Great East Japan Earthquake was one of the largest earthquakes ever recorded in global history. The damage was spread over a wide area, with the worst-hit areas being Iwate, Miyagi and Fukushima prefectures. In this paper we report on the damage and the impact of the damage to describe the health consequences among disaster victims in Iwate Prefecture. In Iwate Prefecture the tsunami claimed 4659 lives, with 1633 people missing. In addition to electricity, water and gas being cut off following the disaster, communication functions were paralysed and there was a lack of gasoline. Medical and public health teams from Iwate Prefecture and around the country, including many different specialists, engaged in a variety of public health activities mainly at evacuation centres, including medical and mental health care and activities to prevent infectious diseases. Given the many fatalities, there were relatively few patients who required medical treatment for major injuries. However, there were significant medical needs in the subacute and chronic phases of care in evacuation centres, with great demand for medical treatment and public health assistance, measures to counteract infection and mental health care. By referring to past experiences of national and international large-scale disasters, it was possible to respond effectively to the health-related challenges. However, there are still challenges concerning how to share information and coordinate overall activities among multiple public health response teams. Further examination will be required to ensure better preparedness in response to future disasters.

  2. Impact of natural disaster combined with nuclear power plant accidents on local medical services: a case study of Minamisoma Municipal General Hospital after the Great East Japan Earthquake.

    Science.gov (United States)

    Kodama, Yuko; Oikawa, Tomoyoshi; Hayashi, Kaoru; Takano, Michiko; Nagano, Mayumi; Onoda, Katsuko; Yoshida, Toshiharu; Takada, Akemi; Hanai, Tatsuo; Shimada, Shunji; Shimada, Satoko; Nishiuchi, Yasuyuki; Onoda, Syuichi; Monma, Kazuo; Tsubokura, Masaharu; Matsumura, Tomoko; Kami, Masahiro; Kanazawa, Yukio

    2014-12-01

    To elucidate the impacts of nuclear plant accidents on neighboring medical centers, we investigated the operations of our hospital within the first 10 days of the Great East Japan Earthquake followed by the Fukushima Daiichi nuclear power plant accident. Data were extracted from medical records and hospital administrative records covering 11 to 20 March 2011. Factual information on the disaster was obtained from public access media. A total of 622 outpatients and 241 inpatients were treated. Outpatients included 43 injured, 6 with cardiopulmonary arrest, and 573 with chronic diseases. Among the 241 inpatients, 5 died, 137 were discharged, and the other 99 were transferred to other hospitals. No communication methods or medical or food supplies were available for 4 days after the earthquake. Hospital directors allowed employees to leave the hospital on day 4. All 39 temporary workers were evacuated immediately, and 71 of 239 full-time employees remained. These employees handled extra tasks besides patient care and patient transfer to other hospitals. Committed effective doses indicating the magnitude of health risks due to an intake of radioactive cesium into the human body were found to be minimal according to internal radiation exposure screening carried out from July to August 2011. After the disaster, hospitals located within the evacuation zone of a 30-km radius of the nuclear power plant were isolated. Maintenance of the health care system in such an event becomes difficult.

  3. Connecting slow earthquakes to huge earthquakes.

    Science.gov (United States)

    Obara, Kazushige; Kato, Aitaro

    2016-07-15

    Slow earthquakes are characterized by a wide spectrum of fault slip behaviors and seismic radiation patterns that differ from those of traditional earthquakes. However, slow earthquakes and huge megathrust earthquakes can have common slip mechanisms and are located in neighboring regions of the seismogenic zone. The frequent occurrence of slow earthquakes may help to reveal the physics underlying megathrust events as useful analogs. Slow earthquakes may function as stress meters because of their high sensitivity to stress changes in the seismogenic zone. Episodic stress transfer to megathrust source faults leads to an increased probability of triggering huge earthquakes if the adjacent locked region is critically loaded. Careful and precise monitoring of slow earthquakes may provide new information on the likelihood of impending huge earthquakes. Copyright © 2016, American Association for the Advancement of Science.

  4. Recent Inflation of Kilauea Volcano

    Science.gov (United States)

    Miklius, A.; Poland, M.; Desmarais, E.; Sutton, A.; Orr, T.; Okubo, P.

    2006-12-01

    Over the last three years, geodetic monitoring networks and satellite radar interferometry have recorded substantial inflation of Kilauea's magma system, while the Pu`u `O`o eruption on the east rift zone has continued unabated. Combined with the approximate doubling of carbon dioxide emission rates at the summit during this period, these observations indicate that the magma supply rate to the volcano has increased. Since late 2003, the summit area has risen over 20 cm, and a 2.5 km-long GPS baseline across the summit area has extended almost half a meter. The center of inflation has been variable, with maximum uplift shifting from an area near the center of the caldera to the southeastern part of the caldera in 2004-2005. In 2006, the locus of inflation shifted again, to the location of the long-term magma reservoir in the southern part of the caldera - the same area that had subsided more than 1.5 meters during the last 23 years of the ongoing eruption. In addition, the southwest rift zone reversed its long-term trend of subsidence and began uplifting in early 2006. The east rift zone has shown slightly accelerated rates of extension, but with a year-long hiatus following the January 2005 south flank aseismic slip event. Inflation rates have varied greatly. Accelerated rates of extension and uplift in early 2005 and 2006 were also associated with increased seismicity. Seismicity occurred not only at inflation centers, but was also triggered on the normal faulting area northwest of the caldera and the strike-slip faulting area in the upper east rift zone. In early 2006, at about the time that we started recording uplift on the southwest rift zone, the rate of earthquakes extending from the summit into the southwest rift zone at least quadrupled. The most recent previous episode of inflation at Kilauea, in 2002, may have resulted from reduced lava- transport capacity, as it was associated with decreased outflow at the eruption site. In contrast, eruption volumes

  5. Ambulance Dispatches From Unaffected Areas After the Great East Japan Earthquake: Impact on Emergency Care in the Unaffected Areas.

    Science.gov (United States)

    Hagihara, Akihito; Onozuka, Daisuke; Nagata, Takashi; Abe, Takeru; Hasegawa, Manabu; Nabeshima, Yoshihiro

    2015-12-01

    Although dispatching ambulance crews from unaffected areas to a disaster zone is inevitable when a major disaster occurs, the effect on emergency care in the unaffected areas has not been studied. We evaluated whether dispatching ambulance crews from unaffected prefectures to those damaged by the Great East Japan Earthquake was associated with reduced resuscitation outcomes in out-of-hospital cardiac arrest (OHCA) cases in the unaffected areas. We used the Box-Jenkins transfer function model to assess the relationship between ambulance crew dispatches and return of spontaneous circulation (ROSC) before hospital arrival or 1-month survival after the cardiac event. In a model whose output was the rate of ROSC before hospital arrival, dispatching 1000 ambulance crews was associated with a 0.474% decrease in the rate of ROSC after the dispatch in the prefectures (p=0.023). In a model whose output was the rate of 1-month survival, dispatching 1000 ambulance crews was associated with a 0.502% decrease in the rate of 1-month survival after the dispatch in the prefectures (p=0.011). The dispatch of ambulances from unaffected prefectures to earthquake-stricken areas was associated with a subsequent decrease in the ROSC and 1-month survival rates in OHCA cases in the unaffected prefectures.

  6. Eruptive viscosity and volcano morphology

    International Nuclear Information System (INIS)

    Posin, S.B.; Greeley, R.

    1988-01-01

    Terrestrial central volcanoes formed predominantly from lava flows were classified as shields, stratovolcanoes, and domes. Shield volcanoes tend to be large in areal extent, have convex slopes, and are characterized by their resemblance to inverted hellenic war shields. Stratovolcanoes have concave slopes, whereas domes are smaller and have gentle convex slopes near the vent that increase near the perimeter. In addition to these differences in morphology, several other variations were observed. The most important is composition: shield volcanoes tend to be basaltic, stratovolcanoes tend to be andesitic, and domes tend to be dacitic. However, important exceptions include Fuji, Pico, Mayon, Izalco, and Fuego which have stratovolcano morphologies but are composed of basaltic lavas. Similarly, Ribkwo is a Kenyan shield volcano composed of trachyte and Suswa and Kilombe are shields composed of phonolite. These exceptions indicate that eruptive conditions, rather than composition, may be the primary factors that determine volcano morphology. The objective of this study is to determine the relationships, if any, between eruptive conditions (viscosity, erupted volume, and effusion rate) and effusive volcano morphology. Moreover, it is the goal of this study to incorporate these relationships into a model to predict the eruptive conditions of extraterrestrial (Martian) volcanoes based on their morphology

  7. Analysis simulation of tectonic earthquake impact to the lifetime of radioactive waste container and equivalent dose rate predication in Yucca Mountain geologic repository, Nevada test site, USA

    International Nuclear Information System (INIS)

    Ko, I.S.; Imardjoko, Y.U.; Karnawati, Dwikorita

    2003-01-01

    US policy not to recycle her spent nuclear fuels brings consequence to provide a nuclear waste repository site Yucca Mountain in Nevada, USA, considered the proper one. High-level radioactive waste to be placed into containers and then will be buried in three hundred meter underground tunnels. Tectonic earthquake is the main factor causing container's damage. Goldsim version 6.04.007 simulates mechanism of container's damage due to a great devastating impact load, the collapse of the tunnels. Radionuclide inventories included are U-234, C-14, Tc-99, I-129, Se-79, Pa-231, Np-237, Pu-242, and Pu-239. Simulation carried out in 100,000 years time span. The research goals are: 1). Estimating tunnels stan-up time, and 2). Predicting the equivalent dose rate contributed by the included radionuclides to the human due to radioactive polluted drinking water intake. (author)

  8. Soufriere Hills Volcano

    Science.gov (United States)

    2002-01-01

    In this ASTER image of Soufriere Hills Volcano on Montserrat in the Caribbean, continued eruptive activity is evident by the extensive smoke and ash plume streaming towards the west-southwest. Significant eruptive activity began in 1995, forcing the authorities to evacuate more than 7,000 of the island's original population of 11,000. The primary risk now is to the northern part of the island and to the airport. Small rockfalls and pyroclastic flows (ash, rock and hot gases) are common at this time due to continued growth of the dome at the volcano's summit.This image was acquired on October 29, 2002 by the Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER) on NASA's Terra satellite. With its 14 spectral bands from the visible to the thermal infrared wavelength region, and its high spatial resolution of 15 to 90 meters (about 50 to 300 feet), ASTER images Earth to map and monitor the changing surface of our planet.ASTER is one of five Earth-observing instruments launched December 18, 1999, on NASA's Terra satellite. The instrument was built by Japan's Ministry of Economy, Trade and Industry. A joint U.S./Japan science team is responsible for validation and calibration of the instrument and the data products.The broad spectral coverage and high spectral resolution of ASTER will provide scientists in numerous disciplines with critical information for surface mapping, and monitoring of dynamic conditions and temporal change. Example applications are: monitoring glacial advances and retreats; monitoring potentially active volcanoes; identifying crop stress; determining cloud morphology and physical properties; wetlands evaluation; thermal pollution monitoring; coral reef degradation; surface temperature mapping of soils and geology; and measuring surface heat balance.Dr. Anne Kahle at NASA's Jet Propulsion Laboratory, Pasadena, California, is the U.S. Science team leader; Bjorn Eng of JPL is the project manager. The Terra mission is part of NASA

  9. Twitter earthquake detection: Earthquake monitoring in a social world

    Science.gov (United States)

    Earle, Paul S.; Bowden, Daniel C.; Guy, Michelle R.

    2011-01-01

    The U.S. Geological Survey (USGS) is investigating how the social networking site Twitter, a popular service for sending and receiving short, public text messages, can augment USGS earthquake response products and the delivery of hazard information. Rapid detection and qualitative assessment of shaking events are possible because people begin sending public Twitter messages (tweets) with in tens of seconds after feeling shaking. Here we present and evaluate an earthquake detection procedure that relies solely on Twitter data. A tweet-frequency time series constructed from tweets containing the word "earthquake" clearly shows large peaks correlated with the origin times of widely felt events. To identify possible earthquakes, we use a short-term-average, long-term-average algorithm. When tuned to a moderate sensitivity, the detector finds 48 globally-distributed earthquakes with only two false triggers in five months of data. The number of detections is small compared to the 5,175 earthquakes in the USGS global earthquake catalog for the same five-month time period, and no accurate location or magnitude can be assigned based on tweet data alone. However, Twitter earthquake detections are not without merit. The detections are generally caused by widely felt events that are of more immediate interest than those with no human impact. The detections are also fast; about 75% occur within two minutes of the origin time. This is considerably faster than seismographic detections in poorly instrumented regions of the world. The tweets triggering the detections also provided very short first-impression narratives from people who experienced the shaking.

  10. Tutorial on earthquake rotational effects: historical examples

    Czech Academy of Sciences Publication Activity Database

    Kozák, Jan

    2009-01-01

    Roč. 99, 2B (2009), s. 998-1010 ISSN 0037-1106 Institutional research plan: CEZ:AV0Z30120515 Keywords : rotational seismic models * earthquake rotational effects * historical earthquakes Subject RIV: DC - Siesmology, Volcanology, Earth Structure Impact factor: 1.860, year: 2009

  11. Data assimilation strategies for volcano geodesy

    Science.gov (United States)

    Zhan, Yan; Gregg, Patricia M.

    2017-09-01

    provide variability in the locations of observations results in better model predictions than utilizing fixed locations when the number of available instruments is limited; (5) spotty InSAR data coverage on the flanks of a volcano due to topographic shadows and/or atmospheric interference does not adversely impact the effectiveness of EnKF if the available coverage is > 50%; and (6) snow or glacial obstruction in the center of uplift can adversely impact EnKF forecasts. By utilizing these strategies, we conclude that the EnKF is an effective sequential model-data fusion technique for assimilating multiple geodetic observations to forecast volcanic activity at restless volcanoes.

  12. Volcanoes, Third Edition

    Science.gov (United States)

    Nye, Christopher J.

    It takes confidence to title a smallish book merely “Volcanoes” because of the impliction that the myriad facets of volcanism—chemistry, physics, geology, meteorology, hazard mitigation, and more—have been identified and addressed to some nontrivial level of detail. Robert and Barbara Decker have visited these different facets seamlessly in Volcanoes, Third Edition. The seamlessness comes from a broad overarching, interdisciplinary, professional understanding of volcanism combined with an exceptionally smooth translation of scientific jargon into plain language.The result is a book which will be informative to a very broad audience, from reasonably educated nongeologists (my mother loves it) to geology undergraduates through professional volcanologists. I bet that even the most senior professional volcanologists will learn at least a few things from this book and will find at least a few provocative discussions of subjects they know.

  13. Update earthquake risk assessment in Cairo, Egypt

    Science.gov (United States)

    Badawy, Ahmed; Korrat, Ibrahim; El-Hadidy, Mahmoud; Gaber, Hanan

    2017-07-01

    The Cairo earthquake (12 October 1992; m b = 5.8) is still and after 25 years one of the most painful events and is dug into the Egyptians memory. This is not due to the strength of the earthquake but due to the accompanied losses and damages (561 dead; 10,000 injured and 3000 families lost their homes). Nowadays, the most frequent and important question that should rise is "what if this earthquake is repeated today." In this study, we simulate the same size earthquake (12 October 1992) ground motion shaking and the consequent social-economic impacts in terms of losses and damages. Seismic hazard, earthquake catalogs, soil types, demographics, and building inventories were integrated into HAZUS-MH to produce a sound earthquake risk assessment for Cairo including economic and social losses. Generally, the earthquake risk assessment clearly indicates that "the losses and damages may be increased twice or three times" in Cairo compared to the 1992 earthquake. The earthquake risk profile reveals that five districts (Al-Sahel, El Basateen, Dar El-Salam, Gharb, and Madinat Nasr sharq) lie in high seismic risks, and three districts (Manshiyat Naser, El-Waily, and Wassat (center)) are in low seismic risk level. Moreover, the building damage estimations reflect that Gharb is the highest vulnerable district. The analysis shows that the Cairo urban area faces high risk. Deteriorating buildings and infrastructure make the city particularly vulnerable to earthquake risks. For instance, more than 90 % of the estimated buildings damages are concentrated within the most densely populated (El Basateen, Dar El-Salam, Gharb, and Madinat Nasr Gharb) districts. Moreover, about 75 % of casualties are in the same districts. Actually, an earthquake risk assessment for Cairo represents a crucial application of the HAZUS earthquake loss estimation model for risk management. Finally, for mitigation, risk reduction, and to improve the seismic performance of structures and assure life safety

  14. The Powell Volcano Remote Sensing Working Group Overview

    Science.gov (United States)

    Reath, K.; Pritchard, M. E.; Poland, M. P.; Wessels, R. L.; Biggs, J.; Carn, S. A.; Griswold, J. P.; Ogburn, S. E.; Wright, R.; Lundgren, P.; Andrews, B. J.; Wauthier, C.; Lopez, T.; Vaughan, R. G.; Rumpf, M. E.; Webley, P. W.; Loughlin, S.; Meyer, F. J.; Pavolonis, M. J.

    2017-12-01

    Hazards from volcanic eruptions pose risks to the lives and livelihood of local populations, with potential global impacts to businesses, agriculture, and air travel. The 2015 Global Assessment of Risk report notes that 800 million people are estimated to live within 100 km of 1400 subaerial volcanoes identified as having eruption potential. However, only 55% of these volcanoes have any type of ground-based monitoring. The only methods currently available to monitor these unmonitored volcanoes are space-based systems that provide a global view. However, with the explosion of data techniques and sensors currently available, taking full advantage of these resources can be challenging. The USGS Powell Center Volcano Remote Sensing Working Group is working with many partners to optimize satellite resources for global detection of volcanic unrest and assessment of potential eruption hazards. In this presentation we will describe our efforts to: 1) work with space agencies to target acquisitions from the international constellation of satellites to collect the right types of data at volcanoes with forecasting potential; 2) collaborate with the scientific community to develop databases of remotely acquired observations of volcanic thermal, degassing, and deformation signals to facilitate change detection and assess how these changes are (or are not) related to eruption; and 3) improve usage of satellite observations by end users at volcano observatories that report to their respective governments. Currently, the group has developed time series plots for 48 Latin American volcanoes that incorporate variations in thermal, degassing, and deformation readings over time. These are compared against eruption timing and ground-based data provided by the Smithsonian Institute Global Volcanism Program. Distinct patterns in unrest and eruption are observed at different volcanoes, illustrating the difficulty in developing generalizations, but highlighting the power of remote sensing

  15. Sub-crustal seismic activity beneath Klyuchevskoy Volcano

    Science.gov (United States)

    Carr, M. J.; Droznina, S.; Levin, V. L.; Senyukov, S.

    2013-12-01

    Seismic activity is extremely vigorous beneath the Klyuchevskoy Volcanic Group (KVG). The unique aspect is the distribution in depth. In addition to upper-crustal seismicity, earthquakes take place at depths in excess of 20 km. Similar observations are known in other volcanic regions, however the KVG is unique in both the number of earthquakes and that they occur continuously. Most other instances of deep seismicity beneath volcanoes appear to be episodic or transient. Digital recording of seismic signals started at the KVG in early 2000s.The dense local network reliably locates earthquakes as small as ML~1. We selected records of 20 earthquakes located at depths over 20 km. Selection was based on the quality of the routine locations and the visual clarity of the records. Arrivals of P and S waves were re-picked, and hypocentral parameters re-established. Newl locations fell within the ranges outlined by historical seismicity, confirming the existence of two distinct seismically active regions. A shallower zone is at ~20 km depth, and all hypocenters are to the northeast of KVG, in a region between KVG and Shiveluch volcano. A deeper zone is at ~30 km, and all hypocenters cluster directly beneath the edifice of the Kyuchevskoy volcano. Examination of individual records shows that earthquakes in both zones are tectonic, with well-defined P and S waves - another distinction of the deep seismicity beneath KVG. While the upper seismic zone is unquestionably within the crust, the provenance of the deeper earthquakes is enigmatic. The crustal structure beneath KVG is highly complex, with no agreed-upon definition of the crust-mantle boundary. Rather, a range of values, from under 30 to over 40 km, exists in the literature. Similarly, a range of velocity structures has been reported. Teleseismic receiver functions (RFs) provide a way to position the earthquakes with respect to the crust-mantle boundary. We compare the differential travel times of S and P waves from deep

  16. Volcanoes in Eruption - Set 1

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The word volcano is used to refer to the opening from which molten rock and gas issue from Earth's interior onto the surface, and also to the cone, hill, or mountain...

  17. Volcanoes in Eruption - Set 2

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The word volcano is used to refer to the opening from which molten rock and gas issue from Earth's interior onto the surface, and also to the cone, hill, or mountain...

  18. Volcano warning systems: Chapter 67

    Science.gov (United States)

    Gregg, Chris E.; Houghton, Bruce F.; Ewert, John W.

    2015-01-01

    Messages conveying volcano alert level such as Watches and Warnings are designed to provide people with risk information before, during, and after eruptions. Information is communicated to people from volcano observatories and emergency management agencies and from informal sources and social and environmental cues. Any individual or agency can be both a message sender and a recipient and multiple messages received from multiple sources is the norm in a volcanic crisis. Significant challenges to developing effective warning systems for volcanic hazards stem from the great diversity in unrest, eruption, and post-eruption processes and the rapidly advancing digital technologies that people use to seek real-time risk information. Challenges also involve the need to invest resources before unrest to help people develop shared mental models of important risk factors. Two populations of people are the target of volcano notifications–ground- and aviation-based populations, and volcano warning systems must address both distinctly different populations.

  19. A smartphone application for earthquakes that matter!

    Science.gov (United States)

    Bossu, Rémy; Etivant, Caroline; Roussel, Fréderic; Mazet-Roux, Gilles; Steed, Robert

    2014-05-01

    Smartphone applications have swiftly become one of the most popular tools for rapid reception of earthquake information for the public, some of them having been downloaded more than 1 million times! The advantages are obvious: wherever someone's own location is, they can be automatically informed when an earthquake has struck. Just by setting a magnitude threshold and an area of interest, there is no longer the need to browse the internet as the information reaches you automatically and instantaneously! One question remains: are the provided earthquake notifications always relevant for the public? What are the earthquakes that really matters to laypeople? One clue may be derived from some newspaper reports that show that a while after damaging earthquakes many eyewitnesses scrap the application they installed just after the mainshock. Why? Because either the magnitude threshold is set too high and many felt earthquakes are missed, or it is set too low and the majority of the notifications are related to unfelt earthquakes thereby only increasing anxiety among the population at each new update. Felt and damaging earthquakes are the ones that matter the most for the public (and authorities). They are the ones of societal importance even when of small magnitude. A smartphone application developed by EMSC (Euro-Med Seismological Centre) with the financial support of the Fondation MAIF aims at providing suitable notifications for earthquakes by collating different information threads covering tsunamigenic, potentially damaging and felt earthquakes. Tsunamigenic earthquakes are considered here to be those ones that are the subject of alert or information messages from the PTWC (Pacific Tsunami Warning Centre). While potentially damaging earthquakes are identified through an automated system called EQIA (Earthquake Qualitative Impact Assessment) developed and operated at EMSC. This rapidly assesses earthquake impact by comparing the population exposed to each expected

  20. GLACIERS OF THE KORYAK VOLCANO

    Directory of Open Access Journals (Sweden)

    T. M. Manevich

    2012-01-01

    Full Text Available The paper presents main glaciological characteristics of present-day glaciers located on the Koryaksky volcano. The results of fieldwork (2008–2009 and high-resolution satellite image analysis let us to specify and complete information on modern glacial complex of Koryaksky volcano. Now there are seven glaciers with total area 8.36 km2. Three of them advance, two are in stationary state and one degrades. Moreover, the paper describes the new crater glacier.

  1. Radon emanometry in active volcanoes

    Energy Technology Data Exchange (ETDEWEB)

    Seidel, J.L.; Monnin, M. (CNRS, IN2P3, BP45/F63170 Aubiere (France)); Cejudo, J. (Instituto Nacional de Investigaciones Nucleares, Mexico City)

    1984-01-01

    Radon emission measurements from active volcanoes has, since 1981, been continuously measured at monitoring stations in Mexico and in Costa Rica. Counting of etched alpha tracks on cellulose nitrate LR-115 detectors give varying results at the several stations. Radon emanation at Chichon, where an explosive eruption occurred in 1982, fell down. Radon detection at the active volcano in Colima shows a pattern of very low emission. At the Costa Rica stations located at Poas, Arenal and Irazu, the radon emanation shows regularity.

  2. Large-N in Volcano Settings: Volcanosri

    Science.gov (United States)

    Lees, J. M.; Song, W.; Xing, G.; Vick, S.; Phillips, D.

    2014-12-01

    We seek a paradigm shift in the approach we take on volcano monitoring where the compromise from high fidelity to large numbers of sensors is used to increase coverage and resolution. Accessibility, danger and the risk of equipment loss requires that we develop systems that are independent and inexpensive. Furthermore, rather than simply record data on hard disk for later analysis we desire a system that will work autonomously, capitalizing on wireless technology and in field network analysis. To this end we are currently producing a low cost seismic array which will incorporate, at the very basic level, seismological tools for first cut analysis of a volcano in crises mode. At the advanced end we expect to perform tomographic inversions in the network in near real time. Geophone (4 Hz) sensors connected to a low cost recording system will be installed on an active volcano where triggering earthquake location and velocity analysis will take place independent of human interaction. Stations are designed to be inexpensive and possibly disposable. In one of the first implementations the seismic nodes consist of an Arduino Due processor board with an attached Seismic Shield. The Arduino Due processor board contains an Atmel SAM3X8E ARM Cortex-M3 CPU. This 32 bit 84 MHz processor can filter and perform coarse seismic event detection on a 1600 sample signal in fewer than 200 milliseconds. The Seismic Shield contains a GPS module, 900 MHz high power mesh network radio, SD card, seismic amplifier, and 24 bit ADC. External sensors can be attached to either this 24-bit ADC or to the internal multichannel 12 bit ADC contained on the Arduino Due processor board. This allows the node to support attachment of multiple sensors. By utilizing a high-speed 32 bit processor complex signal processing tasks can be performed simultaneously on multiple sensors. Using a 10 W solar panel, second system being developed can run autonomously and collect data on 3 channels at 100Hz for 6 months

  3. Mud Volcanoes as Exploration Targets on Mars

    Science.gov (United States)

    Allen, Carlton C.; Oehler, Dorothy Z.

    2010-01-01

    Tens of thousands of high-albedo mounds occur across the southern part of the Acidalia impact basin on Mars. These structures have geologic, physical, mineralogic, and morphologic characteristics consistent with an origin from a sedimentary process similar to terrestrial mud volcanism. The potential for mud volcanism in the Northern Plains of Mars has been recognized for some time, with candidate mud volcanoes reported from Utopia, Isidis, northern Borealis, Scandia, and the Chryse-Acidalia region. We have proposed that the profusion of mounds in Acidalia is a consequence of this basin's unique geologic setting as the depocenter for the tune fraction of sediments delivered by the outflow channels from the highlands.

  4. Seismicity patterns during a period of inflation at Sierra Negra volcano, Galápagos Ocean Island Chain

    Science.gov (United States)

    Davidge, Lindsey; Ebinger, Cynthia; Ruiz, Mario; Tepp, Gabrielle; Amelung, Falk; Geist, Dennis; Coté, Dustin; Anzieta, Juan

    2017-03-01

    Basaltic shield volcanoes of the western Galápagos islands are among the most rapidly deforming volcanoes worldwide, but little was known of the internal structure and brittle deformation processes accompanying inflation and deflation cycles. A 15-station broadband seismic array was deployed on and surrounding Sierra Negra volcano, Galápagos from July 2009 through June 2011 to characterize seismic strain patterns during an inter-eruption inflation period and to evaluate single and layered magma chamber models for ocean island volcanoes. We compare precise earthquake locations determined from a 3D velocity model and from a double difference cluster method. Using first-motion of P-arrivals, we determine focal mechanisms for 8 of the largest earthquakes (ML ≤ 1.5) located within the array. Most of the 2382 earthquakes detected by the array occurred beneath the broad (∼9 km-wide) Sierra Negra caldera, at depths from surface to about 8 km below sea level. Although outside our array, frequent and larger magnitude (ML ≤ 3.4) earthquakes occurred at Alcedo and Fernandina volcano, and in a spatial cluster beneath the shallow marine platform between Fernandina and Sierra Negra volcanoes. The time-space relations and focal mechanism solutions from a 4-day long period of intense seismicity June 4-9, 2010 along the southeastern flank of Sierra Negra suggests that the upward-migrating earthquake swarm occurred during a small volume intrusion at depths 5-8 km subsurface, but there was no detectable signal in InSAR data to further constrain geometry and volume. Focal mechanisms of earthquakes beneath the steep intra-caldera faults and along the ring fault system are reverse and strike-slip. These new seismicity data integrated with tomographic, geodetic, and petrological models indicate a stratified magmatic plumbing system: a shallow sill beneath the large caldera that is supplied by magma from a large volume deeper feeding system. The large amplitude inter

  5. Vertical Motions of Oceanic Volcanoes

    Science.gov (United States)

    Clague, D. A.; Moore, J. G.

    2006-12-01

    Oceanic volcanoes offer abundant evidence of changes in their elevations through time. Their large-scale motions begin with a period of rapid subsidence lasting hundreds of thousands of years caused by isostatic compensation of the added mass of the volcano on the ocean lithosphere. The response is within thousands of years and lasts as long as the active volcano keeps adding mass on the ocean floor. Downward flexure caused by volcanic loading creates troughs around the growing volcanoes that eventually fill with sediment. Seismic surveys show that the overall depression of the old ocean floor beneath Hawaiian volcanoes such as Mauna Loa is about 10 km. This gross subsidence means that the drowned shorelines only record a small part of the total subsidence the islands experienced. In Hawaii, this history is recorded by long-term tide-gauge data, the depth in drill holes of subaerial lava flows and soil horizons, former shorelines presently located below sea level. Offshore Hawaii, a series of at least 7 drowned reefs and terraces record subsidence of about 1325 m during the last half million years. Older sequences of drowned reefs and terraces define the early rapid phase of subsidence of Maui, Molokai, Lanai, Oahu, Kauai, and Niihau. Volcanic islands, such as Maui, tip down toward the next younger volcano as it begins rapid growth and subsidence. Such tipping results in drowned reefs on Haleakala as deep as 2400 m where they are tipped towards Hawaii. Flat-topped volcanoes on submarine rift zones also record this tipping towards the next younger volcano. This early rapid subsidence phase is followed by a period of slow subsidence lasting for millions of years caused by thermal contraction of the aging ocean lithosphere beneath the volcano. The well-known evolution along the Hawaiian chain from high to low volcanic island, to coral island, and to guyot is due to this process. This history of rapid and then slow subsidence is interrupted by a period of minor uplift

  6. Impact of the Great East Japan Earthquake and tsunami on health, medical care and public health systems in Iwate Prefecture, Japan, 2011

    Directory of Open Access Journals (Sweden)

    Masaru Nohara

    2011-12-01

    Full Text Available Problem: The Great East Japan Earthquake was one of the largest earthquakes ever recorded in global history. The damage was spread over a wide area, with the worst-hit areas being Iwate, Miyagi and Fukushima prefectures. In this paper we report on the damage and the impact of the damage to describe the health consequences among disaster victims in Iwate Prefecture.Context: In Iwate Prefecture the tsunami claimed 4659 lives, with 1633 people missing. In addition to electricity, water and gas being cut off following the disaster, communication functions were paralysed and there was a lack of gasoline.Action: Medical and public health teams from Iwate Prefecture and around the country, including many different specialists, engaged in a variety of public health activities mainly at evacuation centres, including medical and mental health care and activities to prevent infectious diseases.Outcome: Given the many fatalities, there were relatively few patients who required medical treatment for major injuries. However, there were significant medical needs in the subacute and chronic phases of care in evacuation centres, with great demand for medical treatment and public health assistance, measures to counteract infection and mental health care.Discussion: By referring to past experiences of national and international large-scale disasters, it was possible to respond effectively to the health-related challenges. However, there are still challenges concerning how to share information and coordinate overall activities among multiple public health response teams. Further examination will be required to ensure better preparedness in response to future disasters.

  7. Body Wave and Ambient Noise Tomography of Makushin Volcano, Alaska

    Science.gov (United States)

    Lanza, F.; Thurber, C. H.; Syracuse, E. M.; Ghosh, A.; LI, B.; Power, J. A.

    2017-12-01

    Located in the eastern portion of the Alaska-Aleutian subduction zone, Makushin Volcano is among the most active volcanoes in the United States and has been classified as high threat based on eruptive history and proximity to the City of Unalaska and international air routes. In 2015, five individual seismic stations and three mini seismic arrays of 15 stations each were deployed on Unalaska island to supplement the Alaska Volcano Observatory (AVO) permanent seismic network. This temporary array was operational for one year. Taking advantage of the increased azimuthal coverage and the array's increased earthquake detection capability, we developed body-wave Vp and Vp/Vs seismic images of the velocity structure beneath the volcano. Body-wave tomography results show a complex structure with the upper 5 km of the crust dominated by both positive and negative Vp anomalies. The shallow high-Vp features possibly delineate remnant magma pathways or conduits. Low-Vp regions are found east of the caldera at approximately 6-9 km depth. This is in agreement with previous tomographic work and geodetic models, obtained using InSAR data, which had identified this region as a possible long-term source of magma. We also observe a high Vp/Vs feature extending between 7 and 12 km depth below the caldera, possibly indicating partial melting, although the resolution is diminished at these depths. The distributed stations allow us to further complement body-wave tomography with ambient noise imaging and to obtain higher quality of Vs images. Our data processing includes single station data preparation and station-pair cross-correlation steps (Bensen et al., 2007), and the use of the phase weighted stacking method (Schimmel and Gallart, 2007) to improve the signal-to-noise ratio of the cross-correlations. We will show surface-wave dispersion curves, group velocity maps, and ultimately a 3D Vs image. By performing both body wave and ambient noise tomography, we provide a high

  8. Monitoring a restless volcano: The 2004 eruption of Mount St. Helens

    Science.gov (United States)

    Gardner, C.

    2005-01-01

    Although the precise course of volcanic activity is difficult to predict, volcanologists are pretty adept at interpreting volcanic signals from well-monitored volcanoes in order to make short-term forecasts. Various monitoring tools record effects to give us warning before eruptions, changes in eruptive behavior during eruptions, or signals that an eruption is ending. Foremost among these tools is seismic monitoring. The character, size, depth and rate of earthquakes are all important to the interpretation of what is happening belowground. The first inkling of renewed activity at Mount St. Helens began in the early hours of Sept. 23, when a seismic swarm - tens to hundreds of earthquakes over days to a week - began beneath the volcano. This article details the obervations made during the eruptive sequence.

  9. Geophysical data collection using an interactive personal computer system. Part 1. ; Experimental monitoring of Suwanosejima volcano

    Energy Technology Data Exchange (ETDEWEB)

    Iguchi, M. (Kyoto Univerdity, Kyoto (Japan). Disaster Prevention Reserach Institute)

    1991-10-15

    In the article, a computer-communication system was developed in order to collect geophysical data from remote volcanos via a public telephpne network. This system is composed of a host presonal computer at an observatory and several personal computers as terminals at remote stations. Each terminal acquires geophysical data, such as seismic, intrasonic, and ground deformation date. These gara are stored in the terminals temporarily, and transmitted to the host computer upon command from host computer. Experimental monitoring was conducted between Sakurajima Volcanological Observatory and several statins in the Satsunan Islands and southern Kyushu. The seismic and eruptive activities of Suwanosejima volcano were monitored by this system. Consequently, earthquakes and air-shocks accompanied by the explosive activity were observed. B-type earthquakes occurred prio to the relatively prolonged eruptive activity. Intermittent occurrences of volcanic tremors were also clearly recognized from the change in mean amplitubes of seismic waves. 7 refs., 10 figs., 2 tabs.

  10. Chiliques volcano, Chile

    Science.gov (United States)

    2002-01-01

    A January 6, 2002 ASTER nighttime thermal infrared image of Chiliques volcano in Chile shows a hot spot in the summit crater and several others along the upper flanks of the edifice, indicating new volcanic activity. Examination of an earlier nighttime thermal infrared image from May 24,2000 showed no thermal anomaly. Chiliques volcano was previously thought to be dormant. Rising to an elevation of 5778 m, Chiliques is a simple stratovolcano with a 500-m-diameter circular summit crater. This mountain is one of the most important high altitude ceremonial centers of the Incas. It is rarely visited due to its difficult accessibility. Climbing to the summit along Inca trails, numerous ruins are encountered; at the summit there are a series of constructions used for rituals. There is a beautiful lagoon in the crater that is almost always frozen.The daytime image was acquired on November 19, 2000 and was created by displaying ASTER bands 1,2 and 3 in blue, green and red. The nighttime image was acquired January 6, 2002, and is a color-coded display of a single thermal infrared band. The hottest areas are white, and colder areas are darker shades of red. Both images cover an area of 7.5 x 7.5 km, and are centered at 23.6 degrees south latitude, 67.6 degrees west longitude.Both images cover an area of 7.5 x 7.5 km, and are centered at 23.6 degrees south latitude, 67.6 degrees west longitude.These images were acquired by the Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER) on NASA's Terra satellite. With its 14spectral bands from the visible to the thermal infrared wavelength region, and its high spatial resolution of 15 to 90 meters (about 50 to 300 feet), ASTER will image Earth for the next 6 years to map and monitor the changing surface of our planet.ASTER is one of five Earth-observing instruments launched December 18,1999, on NASA's Terra satellite. The instrument was built by Japan's Ministry of Economy, Trade and Industry. A joint U

  11. Volcano ecology: flourishing on the flanks of Mount St. Helens

    Science.gov (United States)

    Rhonda Mazza; Charlie Crisafulli

    2016-01-01

    Mount St. Helens’ explosive eruption on May 18, 1980, was a pivotal moment in the field of disturbance ecology. The subsequent sustained, integrated research effort has shaped the development of volcano ecology, an emerging field of focused research. Excessive heat, burial, and impact force are some of the disturbance mechanisms following an eruption. They are also...

  12. Perception of earthquake risk in Taiwan: effects of gender and past earthquake experience.

    Science.gov (United States)

    Kung, Yi-Wen; Chen, Sue-Huei

    2012-09-01

    This study explored how individuals in Taiwan perceive the risk of earthquake and the relationship of past earthquake experience and gender to risk perception. Participants (n= 1,405), including earthquake survivors and those in the general population without prior direct earthquake exposure, were selected and interviewed through a computer-assisted telephone interviewing procedure using a random sampling and stratification method covering all 24 regions of Taiwan. A factor analysis of the interview data yielded a two-factor structure of risk perception in regard to earthquake. The first factor, "personal impact," encompassed perception of threat and fear related to earthquakes. The second factor, "controllability," encompassed a sense of efficacy of self-protection in regard to earthquakes. The findings indicated prior earthquake survivors and females reported higher scores on the personal impact factor than males and those with no prior direct earthquake experience, although there were no group differences on the controllability factor. The findings support that risk perception has multiple components, and suggest that past experience (survivor status) and gender (female) affect the perception of risk. Exploration of potential contributions of other demographic factors such as age, education, and marital status to personal impact, especially for females and survivors, is discussed. Future research on and intervention program with regard to risk perception are suggested accordingly. © 2012 Society for Risk Analysis.

  13. Smoking prevalence increases following Canterbury earthquakes.

    Science.gov (United States)

    Erskine, Nick; Daley, Vivien; Stevenson, Sue; Rhodes, Bronwen; Beckert, Lutz

    2013-01-01

    A magnitude 7.1 earthquake hit Canterbury in September 2010. This earthquake and associated aftershocks took the lives of 185 people and drastically changed residents' living, working, and social conditions. To explore the impact of the earthquakes on smoking status and levels of tobacco consumption in the residents of Christchurch. Semistructured interviews were carried out in two city malls and the central bus exchange 15 months after the first earthquake. A total of 1001 people were interviewed. In August 2010, prior to any earthquake, 409 (41%) participants had never smoked, 273 (27%) were currently smoking, and 316 (32%) were ex-smokers. Since the September 2010 earthquake, 76 (24%) of the 316 ex-smokers had smoked at least one cigarette and 29 (38.2%) had smoked more than 100 cigarettes. Of the 273 participants who were current smokers in August 2010, 93 (34.1%) had increased consumption following the earthquake, 94 (34.4%) had not changed, and 86 (31.5%) had decreased their consumption. 53 (57%) of the 93 people whose consumption increased reported that the earthquake and subsequent lifestyle changes as a reason to increase smoking. 24% of ex-smokers resumed smoking following the earthquake, resulting in increased smoking prevalence. Tobacco consumption levels increased in around one-third of current smokers.

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

    Science.gov (United States)

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

    2014-07-01

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

  15. Twitter earthquake detection: earthquake monitoring in a social world

    Directory of Open Access Journals (Sweden)

    Daniel C. Bowden

    2011-06-01

    Full Text Available The U.S. Geological Survey (USGS is investigating how the social networking site Twitter, a popular service for sending and receiving short, public text messages, can augment USGS earthquake response products and the delivery of hazard information. Rapid detection and qualitative assessment of shaking events are possible because people begin sending public Twitter messages (tweets with in tens of seconds after feeling shaking. Here we present and evaluate an earthquake detection procedure that relies solely on Twitter data. A tweet-frequency time series constructed from tweets containing the word “earthquake” clearly shows large peaks correlated with the origin times of widely felt events. To identify possible earthquakes, we use a short-term-average, long-term-average algorithm. When tuned to a moderate sensitivity, the detector finds 48 globally-distributed earthquakes with only two false triggers in five months of data. The number of detections is small compared to the 5,175 earthquakes in the USGS global earthquake catalog for the same five-month time period, and no accurate location or magnitude can be assigned based on tweet data alone. However, Twitter earthquake detections are not without merit. The detections are generally caused by widely felt events that are of more immediate interest than those with no human impact. The detections are also fast; about 75% occur within two minutes of the origin time. This is considerably faster than seismographic detections in poorly instrumented regions of the world. The tweets triggering the detections also provided very short first-impression narratives from people who experienced the shaking.

  16. Dynamic behavior of Kilauea Volcano and its relation to hydrothermal systems and geothermal energy

    Science.gov (United States)

    Kauhikaua, Jim; Moore, R.B.; ,

    1993-01-01

    Exploitation of hydrothermal systems on active basaltic volcanoes poses some unique questions about the role of volcanism and hydrothermal system evolution. Volcanic activity creates and maintains hydrothermal systems while earthquakes create permeable fractures that, at least temporarily, enhance circulation. Magma and water, possibly hydrothermal water, can interact violently to produce explosive eruptions. Finally, we speculate on whether volcanic behavior can be affected by high rates of heat extraction.

  17. Analysis of Distribution of Volcanoes around the Korean Peninsula and the Potential Effects on Korea

    Science.gov (United States)

    Choi, Eun-kyeong; Kim, Sung-wook

    2017-04-01

    Since the scale and disaster characteristics of volcanic eruptions are determined by their geological features, it is important not only to grasp the current states of the volcanoes in neighboring countries around the Korean Peninsula, but also to analyze the tectonic settings, tectonic regions, geological features, volcanic types, and eruption histories of these volcanoes. Volcanic data were based on the volcano information registered with the Global Volcanism Program at the Smithsonian Institute. We created a database of 289 volcanoes around Korea, Japan, China, Taiwan, and the Kamchatka area in Russia, and then identified a high-risk group of 29 volcanoes that are highly likely to affect the region, based on conditions such as volcanic activity, types of rock at risk of eruption, distance from Seoul, and volcanoes having Plinian eruption history with volcanic explosivity index (VEI) of 4 or more. We selected 29 hazardous volcanoes, including Baekdusan, Ulleungdo, and 27 Japanese volcanoes that can cause widespread ashfall on the Korean peninsula by potentially explosive eruptions. In addition, we identified ten volcanoes that should be given the highest priority, through an analysis of data available in literature, such as volcanic ash dispersion results from previous Japanese eruptions, the definition of a large-scale volcano used by Japan's Cabinet Office, and examination of cumulative magma layer volumes from Japan's quaternary volcanoes. We expect that predicting the extent of the spread of ash caused by this hazardous activity and analyzing its impact on the Korean peninsula will be help to predict volcanic ash damage as well as provide direction for hazard mitigation research. Acknowledgements This research was supported by a grant [MPSS-NH-2015-81] through the Disaster and Safety Management Institute funded by Ministry of Public Safety and Security of Korean government.

  18. A comparison of the medium-term impact and recovery of the Pakistan floods and the Haiti earthquake: objective and subjective measures.

    Science.gov (United States)

    Weiss, William M; Kirsch, Thomas D; Doocy, Shannon; Perrin, Paul

    2014-06-01

    The 2010 Haiti earthquake and Pakistan floods were similar in their massive human impact. Although the specific events were very different, the humanitarian response to disasters is supposed to achieve the same ends. This paper contrasts the disaster effects and aims to contrast the medium-term response. In January 2011, similarly structured population-based surveys were carried out in the most affected areas using stratified cluster designs (80×20 in Pakistan and 60×20 in Haiti) with probability proportional to size sampling. Displacement persisted in Haiti and Pakistan at 53% and 39% of households, respectively. In Pakistan, 95% of households reported damage to their homes and loss of income or livelihoods, and in Haiti, the rates were 93% and 85%, respectively. Frequency of displacement, and income or livelihood loss, were significantly higher in Pakistan, whereas disaster-related deaths or injuries were significantly more prevalent in Haiti. Given the rise in disaster frequency and costs, and the volatility of humanitarian funding streams as a result of the recent global financial crisis, it is increasingly important to measure the impact of humanitarian response against the goal of a return to normalcy.

  19. The socioeconomic impact of international aid: a qualitative study of healthcare recovery in post-earthquake Haiti and implications for future disaster relief.

    Science.gov (United States)

    Kligerman, Maxwell; Walmer, David; Bereknyei Merrell, Sylvia

    2017-05-01

    We assessed healthcare provider perspectives of international aid four years after the Haiti Earthquake to better understand the impact of aid on the Haitian healthcare system and learn best practices for recovery in future disaster contexts. We conducted 22 semi-structured interviews with the directors of local, collaborative, and aid-funded healthcare facilities in Leogane, Haiti. We coded and analysed the interviews using an iterative method based on a grounded theory approach of data analysis. Healthcare providers identified positive aspects of aid, including acute emergency relief, long-term improved healthcare access, and increased ease of referrals for low-income patients. However, they also identified negative impacts of international aid, including episodes of poor quality care, internal brain drain, competition across facilities, decrease in patient flow to local facilities, and emigration of Haitian doctors to abroad. As Haiti continues to recover, it is imperative for aid institutions and local healthcare facilities to develop a more collaborative relationship to transition acute relief to sustainable capacity building. In future disaster contexts, aid institutions should specifically utilise quality of care metrics, NGO Codes of Conduct, Master Health Facility Lists, and sliding scale payment systems to improve disaster response.

  20. Global Volcano Mortality Risks and Distribution

    Data.gov (United States)

    National Aeronautics and Space Administration — Global Volcano Mortality Risks and Distribution is a 2.5 minute grid representing global volcano mortality risks. The data set was constructed using historical...

  1. The relationship between earthquake exposure and posttraumatic stress disorder in 2013 Lushan earthquake

    Science.gov (United States)

    Wang, Yan; Lu, Yi

    2018-01-01

    The objective of this study is to explore the relationship between earthquake exposure and the incidence of PTSD. A stratification random sample survey was conducted to collect data in the Longmenshan thrust fault after Lushan earthquake three years. We used the Children's Revised Impact of Event Scale (CRIES-13) and the Earthquake Experience Scale. Subjects in this study included 3944 school student survivors in local eleven schools. The prevalence of probable PTSD is relatively higher, when the people was trapped in the earthquake, was injured in the earthquake or have relatives who died in the earthquake. It concluded that researchers need to pay more attention to the children and adolescents. The government should pay more attention to these people and provide more economic support.

  2. Space Radar Image of Kilauea Volcano, Hawaii

    Science.gov (United States)

    1994-01-01

    This is a deformation map of the south flank of Kilauea volcano on the big island of Hawaii, centered at 19.5 degrees north latitude and 155.25 degrees west longitude. The map was created by combining interferometric radar data -- that is data acquired on different passes of the space shuttle which are then overlayed to obtain elevation information -- acquired by the Spaceborne Imaging Radar-C/X-band Synthetic Aperture Radar during its first flight in April 1994 and its second flight in October 1994. The area shown is approximately 40 kilometers by 80 kilometers (25 miles by 50 miles). North is toward the upper left of the image. The colors indicate the displacement of the surface in the direction that the radar instrument was pointed (toward the right of the image) in the six months between images. The analysis of ground movement is preliminary, but appears consistent with the motions detected by the Global Positioning System ground receivers that have been used over the past five years. The south flank of the Kilauea volcano is among the most rapidly deforming terrains on Earth. Several regions show motions over the six-month time period. Most obvious is at the base of Hilina Pali, where 10 centimeters (4 inches) or more of crustal deformation can be seen in a concentrated area near the coastline. On a more localized scale, the currently active Pu'u O'o summit also shows about 10 centimeters (4 inches) of change near the vent area. Finally, there are indications of additional movement along the upper southwest rift zone, just below the Kilauea caldera in the image. Deformation of the south flank is believed to be the result of movements along faults deep beneath the surface of the volcano, as well as injections of magma, or molten rock, into the volcano's 'plumbing' system. Detection of ground motions from space has proven to be a unique capability of imaging radar technology. Scientists hope to use deformation data acquired by SIR-C/X-SAR and future imaging

  3. Systematic radon survey over active volcanoes

    Energy Technology Data Exchange (ETDEWEB)

    Seidel, J.L.; Monnin, M.; Garcia Vindas, J.R. [Centre National de la Recherche Cientifique, Montpellier (France). Lab. GBE; Ricard, L.P.; Staudacher, T. [Observatoire Volcanologique Du Pitou de la Fournaise, La Plaine des Cafres (France)

    1999-08-01

    Data obtained since 1993 on Costa Rica volcanos are presented and radon anomalies recorded before the eruption of the Irazu volcano (December 8, 1994) are discussed. The Piton de la Fournaise volcano is inactive since mid 1992. The influence of the external parameters on the radon behaviour is studied and the type of perturbations induced on short-term measurements are individuate.

  4. Monitoring Volcanoes by Use of Air-Dropped Sensor Packages

    Science.gov (United States)

    Kedar, Sharon; Rivellini, Tommaso; Webb, Frank; Blaes, Brent; Bracho, Caroline; Lockhart, Andrew; McGee, Ken

    2003-01-01

    Sensor packages that would be dropped from airplanes have been proposed for pre-eruption monitoring of physical conditions on the flanks of awakening volcanoes. The purpose of such monitoring is to gather data that could contribute to understanding and prediction of the evolution of volcanic systems. Each sensor package, denoted a volcano monitoring system (VMS), would include a housing with a parachute attached at its upper end and a crushable foam impact absorber at its lower end (see figure). The housing would contain survivable low-power instrumentation that would include a Global Positioning System (GPS) receiver, an inclinometer, a seismometer, a barometer, a thermometer, and CO2 and SO2 analyzers. The housing would also contain battery power, control, data-logging, and telecommunication subsystems. The proposal for the development of the VMS calls for the use of commercially available sensor, power, and telecommunication equipment, so that efforts could be focused on integrating all of the equipment into a system that could survive impact and operate thereafter for 30 days, transmitting data on the pre-eruptive state of a target volcano to a monitoring center. In a typical scenario, VMSs would be dropped at strategically chosen locations on the flanks of a volcano once the volcano had been identified as posing a hazard from any of a variety of observations that could include eyewitness reports, scientific observations from positions on the ground, synthetic-aperture-radar scans from aircraft, and/or remote sensing from aboard spacecraft. Once dropped, the VMSs would be operated as a network of in situ sensors that would transmit data to a local monitoring center. This network would provide observations as part of an integrated volcano-hazard assessment strategy that would involve both remote sensing and timely observations from the in situ sensors. A similar strategy that involves the use of portable sensors (but not dropping of sensors from aircraft) is

  5. Multiphase modelling of mud volcanoes

    Science.gov (United States)

    Colucci, Simone; de'Michieli Vitturi, Mattia; Clarke, Amanda B.

    2015-04-01

    Mud volcanism is a worldwide phenomenon, classically considered as the surface expression of piercement structures rooted in deep-seated over-pressured sediments in compressional tectonic settings. The release of fluids at mud volcanoes during repeated explosive episodes has been documented at numerous sites and the outflows resemble the eruption of basaltic magma. As magma, the material erupted from a mud volcano becomes more fluid and degasses while rising and decompressing. The release of those gases from mud volcanism is estimated to be a significant contributor both to fluid flux from the lithosphere to the hydrosphere, and to the atmospheric budget of some greenhouse gases, particularly methane. For these reasons, we simulated the fluid dynamics of mud volcanoes using a newly-developed compressible multiphase and multidimensional transient solver in the OpenFOAM framework, taking into account the multicomponent nature (CH4, CO2, H2O) of the fluid mixture, the gas exsolution during the ascent and the associated changes in the constitutive properties of the phases. The numerical model has been tested with conditions representative of the LUSI, a mud volcano that has been erupting since May 2006 in the densely populated Sidoarjo regency (East Java, Indonesia), forcing the evacuation of 40,000 people and destroying industry, farmland, and over 10,000 homes. The activity of LUSI mud volcano has been well documented (Vanderkluysen et al., 2014) and here we present a comparison of observed gas fluxes and mud extrusion rates with the outcomes of numerical simulations. Vanderkluysen, L.; Burton, M. R.; Clarke, A. B.; Hartnett, H. E. & Smekens, J.-F. Composition and flux of explosive gas release at LUSI mud volcano (East Java, Indonesia) Geochem. Geophys. Geosyst., Wiley-Blackwell, 2014, 15, 2932-2946

  6. Impacts of Social Network on Therapeutic Community Participation: A Follow-up Survey of Data Gathered after Ya'an Earthquake.

    Science.gov (United States)

    Li, Zhichao; Chen, Yao; Suo, Liming

    2015-01-01

    In recent years, natural disasters and the accompanying health risks have become more frequent, and rehabilitation work has become an important part of government performance. On one hand, social networks play an important role in participants' therapeutic community participation and physical & mental recovery. On the other hand, therapeutic communities with widespread participation can also contribute to community recovery after disaster. This paper described a field study in an earthquake-stricken area of Ya'an. A set of 3-stage follow-up data was obtained concerning with the villagers' participation in therapeutic community, social network status, demographic background, and other factors. The Hierarchical linear Model (HLM) method was used to investigate the determinants of social network on therapeutic community participation. First, social networks have significantly impacts on the annual changes of therapeutic community participation. Second, there were obvious differences in education between groups mobilized by the self-organization and local government. However, they all exerted the mobilization force through the acquaintance networks. Third, local cadre networks of villagers could negatively influence the activities of self-organized therapeutic community, while with positively influence in government-organized therapeutic activities. This paper suggests that relevant government departments need to focus more on the reconstruction and cultivation of villagers' social network and social capital in the process of post-disaster recovery. These findings contribute to better understandings of how social networks influence therapeutic community participation, and what role local government can play in post-disaster recovery and public health improvement after natural disasters.

  7. Earthquake Hazard Analysis Methods: A Review

    Science.gov (United States)

    Sari, A. M.; Fakhrurrozi, A.

    2018-02-01

    One of natural disasters that have significantly impacted on risks and damage is an earthquake. World countries such as China, Japan, and Indonesia are countries located on the active movement of continental plates with more frequent earthquake occurrence compared to other countries. Several methods of earthquake hazard analysis have been done, for example by analyzing seismic zone and earthquake hazard micro-zonation, by using Neo-Deterministic Seismic Hazard Analysis (N-DSHA) method, and by using Remote Sensing. In its application, it is necessary to review the effectiveness of each technique in advance. Considering the efficiency of time and the accuracy of data, remote sensing is used as a reference to the assess earthquake hazard accurately and quickly as it only takes a limited time required in the right decision-making shortly after the disaster. Exposed areas and possibly vulnerable areas due to earthquake hazards can be easily analyzed using remote sensing. Technological developments in remote sensing such as GeoEye-1 provide added value and excellence in the use of remote sensing as one of the methods in the assessment of earthquake risk and damage. Furthermore, the use of this technique is expected to be considered in designing policies for disaster management in particular and can reduce the risk of natural disasters such as earthquakes in Indonesia.

  8. Taking the pulse of Mars via dating of a plume-fed volcano.

    Science.gov (United States)

    Cohen, Benjamin E; Mark, Darren F; Cassata, William S; Lee, Martin R; Tomkinson, Tim; Smith, Caroline L

    2017-10-03

    Mars hosts the solar system's largest volcanoes. Although their size and impact crater density indicate continued activity over billions of years, their formation rates are poorly understood. Here we quantify the growth rate of a Martian volcano by 40 Ar/ 39 Ar and cosmogenic exposure dating of six nakhlites, meteorites that were ejected from Mars by a single impact event at 10.7 ± 0.8 Ma (2σ). We find that the nakhlites sample a layered volcanic sequence with at least four discrete eruptive events spanning 93 ± 12 Ma (1416 ± 7 Ma to 1322 ± 10 Ma (2σ)). A non-radiogenic trapped 40 Ar/ 36 Ar value of 1511 ± 74 (2σ) provides a precise and robust constraint for the mid-Amazonian Martian atmosphere. Our data show that the nakhlite-source volcano grew at a rate of ca. 0.4-0.7 m Ma -1 -three orders of magnitude slower than comparable volcanoes on Earth, and necessitating that Mars was far more volcanically active earlier in its history.Mars hosts the solar system's largest volcanoes, but their formation rates remain poorly constrained. Here, the authors have measured the crystallization and ejection ages of meteorites from a Martian volcano and find that its growth rate was much slower than analogous volcanoes on Earth.

  9. Laboratory volcano geodesy

    Science.gov (United States)

    Færøvik Johannessen, Rikke; Galland, Olivier; Mair, Karen

    2014-05-01

    intrusion can be excavated and photographed from several angles to compute its 3D shape with the same photogrammetry method. Then, the surface deformation pattern can be directly compared with the shape of underlying intrusion. This quantitative dataset is essential to quantitatively test and validate classical volcano geodetic models.

  10. Earthquakes: hydrogeochemical precursors

    Science.gov (United States)

    Ingebritsen, Steven E.; Manga, Michael

    2014-01-01

    Earthquake prediction is a long-sought goal. Changes in groundwater chemistry before earthquakes in Iceland highlight a potential hydrogeochemical precursor, but such signals must be evaluated in the context of long-term, multiparametric data sets.

  11. Ground water and earthquakes

    Energy Technology Data Exchange (ETDEWEB)

    Ts' ai, T H

    1977-11-01

    Chinese folk wisdom has long seen a relationship between ground water and earthquakes. Before an earthquake there is often an unusual change in the ground water level and volume of flow. Changes in the amount of particulate matter in ground water as well as changes in color, bubbling, gas emission, and noises and geysers are also often observed before earthquakes. Analysis of these features can help predict earthquakes. Other factors unrelated to earthquakes can cause some of these changes, too. As a first step it is necessary to find sites which are sensitive to changes in ground stress to be used as sensor points for predicting earthquakes. The necessary features are described. Recording of seismic waves of earthquake aftershocks is also an important part of earthquake predictions.

  12. ASSESSMENT OF EARTHQUAKE HAZARDS ON WASTE LANDFILLS

    DEFF Research Database (Denmark)

    Zania, Varvara; Tsompanakis, Yiannis; Psarropoulos, Prodromos

    Earthquake hazards may arise as a result of: (a) transient ground deformation, which is induced due to seismic wave propagation, and (b) permanent ground deformation, which is caused by abrupt fault dislocation. Since the adequate performance of waste landfills after an earthquake is of outmost...... importance, the current study examines the impact of both types of earthquake hazards by performing efficient finite-element analyses. These took also into account the potential slip displacement development along the geosynthetic interfaces of the composite base liner. At first, the development of permanent...

  13. Bayesian estimation of magma supply, storage, and eruption rates using a multiphysical volcano model: Kīlauea Volcano, 2000-2012

    Science.gov (United States)

    Anderson, Kyle R.; Poland, Michael P.

    2016-08-01

    Estimating rates of magma supply to the world's volcanoes remains one of the most fundamental aims of volcanology. Yet, supply rates can be difficult to estimate even at well-monitored volcanoes, in part because observations are noisy and are usually considered independently rather than as part of a holistic system. In this work we demonstrate a technique for probabilistically estimating time-variable rates of magma supply to a volcano through probabilistic constraint on storage and eruption rates. This approach utilizes Bayesian joint inversion of diverse datasets using predictions from a multiphysical volcano model, and independent prior information derived from previous geophysical, geochemical, and geological studies. The solution to the inverse problem takes the form of a probability density function which takes into account uncertainties in observations and prior information, and which we sample using a Markov chain Monte Carlo algorithm. Applying the technique to Kīlauea Volcano, we develop a model which relates magma flow rates with deformation of the volcano's surface, sulfur dioxide emission rates, lava flow field volumes, and composition of the volcano's basaltic magma. This model accounts for effects and processes mostly neglected in previous supply rate estimates at Kīlauea, including magma compressibility, loss of sulfur to the hydrothermal system, and potential magma storage in the volcano's deep rift zones. We jointly invert data and prior information to estimate rates of supply, storage, and eruption during three recent quasi-steady-state periods at the volcano. Results shed new light on the time-variability of magma supply to Kīlauea, which we find to have increased by 35-100% between 2001 and 2006 (from 0.11-0.17 to 0.18-0.28 km3/yr), before subsequently decreasing to 0.08-0.12 km3/yr by 2012. Changes in supply rate directly impact hazard at the volcano, and were largely responsible for an increase in eruption rate of 60-150% between 2001 and

  14. Bayesian estimation of magma supply, storage, and eruption rates using a multiphysical volcano model: Kīlauea Volcano, 2000–2012

    Science.gov (United States)

    Anderson, Kyle R.; Poland, Michael

    2016-01-01

    Estimating rates of magma supply to the world's volcanoes remains one of the most fundamental aims of volcanology. Yet, supply rates can be difficult to estimate even at well-monitored volcanoes, in part because observations are noisy and are usually considered independently rather than as part of a holistic system. In this work we demonstrate a technique for probabilistically estimating time-variable rates of magma supply to a volcano through probabilistic constraint on storage and eruption rates. This approach utilizes Bayesian joint inversion of diverse datasets using predictions from a multiphysical volcano model, and independent prior information derived from previous geophysical, geochemical, and geological studies. The solution to the inverse problem takes the form of a probability density function which takes into account uncertainties in observations and prior information, and which we sample using a Markov chain Monte Carlo algorithm. Applying the technique to Kīlauea Volcano, we develop a model which relates magma flow rates with deformation of the volcano's surface, sulfur dioxide emission rates, lava flow field volumes, and composition of the volcano's basaltic magma. This model accounts for effects and processes mostly neglected in previous supply rate estimates at Kīlauea, including magma compressibility, loss of sulfur to the hydrothermal system, and potential magma storage in the volcano's deep rift zones. We jointly invert data and prior information to estimate rates of supply, storage, and eruption during three recent quasi-steady-state periods at the volcano. Results shed new light on the time-variability of magma supply to Kīlauea, which we find to have increased by 35–100% between 2001 and 2006 (from 0.11–0.17 to 0.18–0.28 km3/yr), before subsequently decreasing to 0.08–0.12 km3/yr by 2012. Changes in supply rate directly impact hazard at the volcano, and were largely responsible for an increase in eruption rate of 60–150% between

  15. Ionospheric earthquake precursors

    International Nuclear Information System (INIS)

    Bulachenko, A.L.; Oraevskij, V.N.; Pokhotelov, O.A.; Sorokin, V.N.; Strakhov, V.N.; Chmyrev, V.M.

    1996-01-01

    Results of experimental study on ionospheric earthquake precursors, program development on processes in the earthquake focus and physical mechanisms of formation of various type precursors are considered. Composition of experimental cosmic system for earthquake precursors monitoring is determined. 36 refs., 5 figs

  16. Children's Ideas about Earthquakes

    Science.gov (United States)

    Simsek, Canan Lacin

    2007-01-01

    Earthquake, a natural disaster, is among the fundamental problems of many countries. If people know how to protect themselves from earthquake and arrange their life styles in compliance with this, damage they will suffer will reduce to that extent. In particular, a good training regarding earthquake to be received in primary schools is considered…

  17. Earthquake swarms reveal submarine magma unrest induced by distant mega-earthquakes: Andaman Sea region

    Czech Academy of Sciences Publication Activity Database

    Špičák, Aleš; Vaněk, Jiří

    2016-01-01

    Roč. 116, February (2016), s. 155-163 ISSN 1367-9120 Institutional support: RVO:67985530 Keywords : earthquake swarms * magma migration * submarine volcanic arc Subject RIV: DC - Siesmology, Volcanology, Earth Structure Impact factor: 2.335, year: 2016

  18. Morphometry of terrestrial shield volcanoes

    Science.gov (United States)

    Grosse, Pablo; Kervyn, Matthieu

    2018-03-01

    Shield volcanoes are described as low-angle edifices built primarily by the accumulation of successive lava flows. This generic view of shield volcano morphology is based on a limited number of monogenetic shields from Iceland and Mexico, and a small set of large oceanic islands (Hawaii, Galápagos). Here, the morphometry of 158 monogenetic and polygenetic shield volcanoes is analyzed quantitatively from 90-meter resolution SRTM DEMs using the MORVOLC algorithm. An additional set of 24 lava-dominated 'shield-like' volcanoes, considered so far as stratovolcanoes, are documented for comparison. Results show that there is a large variation in shield size (volumes from 0.1 to > 1000 km3), profile shape (height/basal width (H/WB) ratios mostly from 0.01 to 0.1), flank slope gradients (average slopes mostly from 1° to 15°), elongation and summit truncation. Although there is no clear-cut morphometric difference between shield volcanoes and stratovolcanoes, an approximate threshold can be drawn at 12° average slope and 0.10 H/WB ratio. Principal component analysis of the obtained database enables to identify four key morphometric descriptors: size, steepness, plan shape and truncation. Hierarchical cluster analysis of these descriptors results in 12 end-member shield types, with intermediate cases defining a continuum of morphologies. The shield types can be linked in terms of growth stages and shape evolution, related to (1) magma composition and rheology, effusion rate and lava/pyroclast ratio, which will condition edifice steepness; (2) spatial distribution of vents, in turn related to the magmatic feeding system and the tectonic framework, which will control edifice plan shape; and (3) caldera formation, which will condition edifice truncation.

  19. Iridium emissions from Hawaiian volcanoes

    International Nuclear Information System (INIS)

    Finnegan, D.L.; Zoller, W.H.; Miller, T.M.

    1988-01-01

    Particle and gas samples were collected at Mauna Loa volcano during and after its eruption in March and April, 1984 and at Kilauea volcano in 1983, 1984, and 1985 during various phases of its ongoing activity. In the last two Kilauea sampling missions, samples were collected during eruptive activity. The samples were collected using a filterpack system consisting of a Teflon particle filter followed by a series of 4 base-treated Whatman filters. The samples were analyzed by INAA for over 40 elements. As previously reported in the literature, Ir was first detected on particle filters at the Mauna Loa Observatory and later from non-erupting high temperature vents at Kilauea. Since that time Ir was found in samples collected at Kilauea and Mauna Loa during fountaining activity as well as after eruptive activity. Enrichment factors for Ir in the volcanic fumes range from 10,000 to 100,000 relative to BHVO. Charcoal impregnated filters following a particle filter were collected to see if a significant amount of the Ir was in the gas phase during sample collection. Iridium was found on charcoal filters collected close to the vent, no Ir was found on the charcoal filters. This indicates that all of the Ir is in particulate form very soon after its release. Ratios of Ir to F and Cl were calculated for the samples from Mauna Loa and Kilauea collected during fountaining activity. The implications for the KT Ir anomaly are still unclear though as Ir was not found at volcanoes other than those at Hawaii. Further investigations are needed at other volcanoes to ascertain if basaltic volcanoes other than hot spots have Ir enrichments in their fumes

  20. Iridium emissions from Hawaiian volcanoes

    Science.gov (United States)

    Finnegan, D. L.; Zoller, W. H.; Miller, T. M.

    1988-01-01

    Particle and gas samples were collected at Mauna Loa volcano during and after its eruption in March and April, 1984 and at Kilauea volcano in 1983, 1984, and 1985 during various phases of its ongoing activity. In the last two Kilauea sampling missions, samples were collected during eruptive activity. The samples were collected using a filterpack system consisting of a Teflon particle filter followed by a series of 4 base-treated Whatman filters. The samples were analyzed by INAA for over 40 elements. As previously reported in the literature, Ir was first detected on particle filters at the Mauna Loa Observatory and later from non-erupting high temperature vents at Kilauea. Since that time Ir was found in samples collected at Kilauea and Mauna Loa during fountaining activity as well as after eruptive activity. Enrichment factors for Ir in the volcanic fumes range from 10,000 to 100,000 relative to BHVO. Charcoal impregnated filters following a particle filter were collected to see if a significant amount of the Ir was in the gas phase during sample collection. Iridium was found on charcoal filters collected close to the vent, no Ir was found on the charcoal filters. This indicates that all of the Ir is in particulate form very soon after its release. Ratios of Ir to F and Cl were calculated for the samples from Mauna Loa and Kilauea collected during fountaining activity. The implications for the KT Ir anomaly are still unclear though as Ir was not found at volcanoes other than those at Hawaii. Further investigations are needed at other volcanoes to ascertain if basaltic volcanoes other than hot spots have Ir enrichments in their fumes.

  1. Galactic Super-volcano in Action

    Science.gov (United States)

    2010-08-01

    A galactic "super-volcano" in the massive galaxy M87 is erupting and blasting gas outwards, as witnessed by NASA's Chandra X-ray Observatory and NSF's Very Large Array. The cosmic volcano is being driven by a giant black hole in the galaxy's center and preventing hundreds of millions of new stars from forming. Astronomers studying this black hole and its effects have been struck by the remarkable similarities between it and a volcano in Iceland that made headlines earlier this year. At a distance of about 50 million light years, M87 is relatively close to Earth and lies at the center of the Virgo cluster, which contains thousands of galaxies. M87's location, coupled with long observations over Chandra's lifetime, has made it an excellent subject for investigations of how a massive black hole impacts its environment. "Our results show in great detail that supermassive black holes have a surprisingly good control over the evolution of the galaxies in which they live," said Norbert Werner of the Kavli Institute for Particle Astrophysics and Cosmology at Stanford University and the SLAC National Accelerator Laboratory, who led one of two papers describing the study. "And it doesn't stop there. The black hole's reach extends ever farther into the entire cluster, similar to how one small volcano can affect practically an entire hemisphere on Earth." The cluster surrounding M87 is filled with hot gas glowing in X-ray light, which is detected by Chandra. As this gas cools, it can fall toward the galaxy's center where it should continue to cool even faster and form new stars. However, radio observations with the Very Large Array suggest that in M87 jets of very energetic particles produced by the black hole interrupt this process. These jets lift up the relatively cool gas near the center of the galaxy and produce shock waves in the galaxy's atmosphere because of their supersonic speed. The scientists involved in this research have found the interaction of this cosmic

  2. Elastic energy release in great earthquakes and eruptions

    Directory of Open Access Journals (Sweden)

    Agust eGudmundsson

    2014-05-01

    Full Text Available The sizes of earthquakes are measured using well-defined, measurable quantities such as seismic moment and released (transformed elastic energy. No similar measures exist for the sizes of volcanic eruptions, making it difficult to compare the energies released in earthquakes and eruptions. Here I provide a new measure of the elastic energy (the potential mechanical energy associated with magma chamber rupture and contraction (shrinkage during an eruption. For earthquakes and eruptions, elastic energy derives from two sources: (1 the strain energy stored in the volcano/fault zone before rupture, and (2 the external applied load (force, pressure, stress, displacement on the volcano/fault zone. From thermodynamic considerations it follows that the elastic energy released or transformed (dU during an eruption is directly proportional to the excess pressure (pe in the magma chamber at the time of rupture multiplied by the volume decrease (-dVc of the chamber, so that . This formula can be used as a basis for a new eruption magnitude scale, based on elastic energy released, which can be related to the moment-magnitude scale for earthquakes. For very large eruptions (>100 km3, the volume of the feeder-dike is negligible, so that the decrease in chamber volume during an eruption corresponds roughly to the associated volume of erupted materials , so that the elastic energy is . Using a typical excess pressures of 5 MPa, it is shown that the largest known eruptions on Earth, such as the explosive La Garita Caldera eruption (27-28 million years ago and largest single (effusive Colombia River basalt lava flows (15-16 million years ago, both of which have estimated volumes of about 5000 km3, released elastic energy of the order of 10EJ. For comparison, the seismic moment of the largest earthquake ever recorded, the M9.5 1960 Chile earthquake, is estimated at 100 ZJ and the associated elastic energy release at 10EJ.

  3. Global volcanic earthquake swarm database and preliminary analysis of volcanic earthquake swarm duration

    Directory of Open Access Journals (Sweden)

    S. R. McNutt

    1996-06-01

    Full Text Available Global data from 1979 to 1989 pertaining to volcanic earthquake swarms have been compiled into a custom-designed relational database. The database is composed of three sections: 1 a section containing general information on volcanoes, 2 a section containing earthquake swarm data (such as dates of swarm occurrence and durations, and 3 a section containing eruption information. The most abundant and reliable parameter, duration of volcanic earthquake swarms, was chosen for preliminary analysis. The distribution of all swarm durations was found to have a geometric mean of 5.5 days. Precursory swarms were then separated from those not associated with eruptions. The geometric mean precursory swarm duration was 8 days whereas the geometric mean duration of swarms not associated with eruptive activity was 3.5 days. Two groups of precursory swarms are apparent when duration is compared with the eruption repose time. Swarms with durations shorter than 4 months showed no clear relationship with the eruption repose time. However, the second group, lasting longer than 4 months, showed a significant positive correlation with the log10 of the eruption repose period. The two groups suggest that different suites of physical processes are involved in the generation of volcanic earthquake swarms.

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

    Science.gov (United States)

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

    2012-01-01

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

  5. Volcanoes and human history

    Science.gov (United States)

    Cashman, K. V.; Giordano, G.

    2008-10-01

    The study of volcanic hazards leads inevitably to questions of how past cultures have lived in volcanically active regions of the world. Here we summarize linkages between volcanological, archaeological and anthropological studies of historic and prehistoric volcanic eruptions, with the goal of evaluating the impact of past eruptions on human populations to better prepare for future events. We use examples from papers collected in this volume to illustrate ways in which volcanological studies aid archaeological investigations by providing basic stratigraphic markers and information about the nature and timing of specific volcanic events. We then turn to archaeological perspectives, which provide physical evidence of the direct impacts of volcanic eruptions, such as site abandonment and human migration, as well as indirect impacts on local cultures as reflected in human artifacts. Finally we review anthropological studies of societal responses to past and recent volcanic eruptions. We pay particular attention to both the psychological impact of catastrophic events and records of these impacts encoded within oral traditions. Taken together these studies record drastic short-term eruption impacts but adaptation to volcanic activity over the longer term, largely through strategies of adaptive land use.

  6. Crowdsourced earthquake early warning

    Science.gov (United States)

    Minson, Sarah E.; Brooks, Benjamin A.; Glennie, Craig L.; Murray, Jessica R.; Langbein, John O.; Owen, Susan E.; Heaton, Thomas H.; Iannucci, Robert A.; Hauser, Darren L.

    2015-01-01

    Earthquake early warning (EEW) can reduce harm to people and infrastructure from earthquakes and tsunamis, but it has not been implemented in most high earthquake-risk regions because of prohibitive cost. Common consumer devices such as smartphones contain low-cost versions of the sensors used in EEW. Although less accurate than scientific-grade instruments, these sensors are globally ubiquitous. Through controlled tests of consumer devices, simulation of an Mw (moment magnitude) 7 earthquake on California’s Hayward fault, and real data from the Mw 9 Tohoku-oki earthquake, we demonstrate that EEW could be achieved via crowdsourcing.

  7. COMET-LICSAR: Systematic Deformation Monitoring of Fault Zones and Volcanoes with the Sentinel-1 Constellation

    Science.gov (United States)

    Spaans, K.; Wright, T. J.; Hooper, A. J.; Hatton, E. L.; González, P. J.; Bhattarai, S.; Biggs, J.; Crippa, P.; Ebmeier, S. K.; Elliott, J.; Gaddes, M.; Li, Z.; Parsons, B.; Qiu, Q.; McDougall, A.; Walters, R. J.; Weiss, J. R.; Ziebart, M.

    2017-12-01

    The Sentinel-1 constellation represents a major advance in our ability to monitor our planet's hazardous tectonic and volcanic zones. Here we present the latest progress from COMET (*), where we are now providing deformation results to the community for volcanoes and the tectonic belts (**). COMET now responds routinely to most significant continental earthquakes - Sentinel-1 allows us to do this within a few days for most earthquakes. For example, after the M7.8 Kaikoura (New Zealand) earthquake we supplied a processed interferogram to the community just 5 hours and 37 minutes after the Sentinel-1 acquisition. By the end of 2017, we will be producing interferogram products systematically for all earthquakes larger than M 6.0. For deformation data to be useful for preparedness, we need accuracy on the order of 1 mm/yr or better. This requires mass processing of long time series of radar acquisitions. We are currently (July 2017) processing interferograms systematically for the entire Alpine-Himalayan belt ( 9000 x 2000 km) using our LiCSAR chain, making interferograms and coherence products available to the community. By December 2017, we plan to process a wider tectonic area and the majority of subaerial volcanoes. We currently serve displacement and coherence grids, but plan to provide average deformation rates and time series. Results are available through our dedicated portal (**), and are being linked to the ESA G-TEP and EPOS during 2017. We will show the latest results for tectonics and volcanism, and discuss how these can be used to build value-added products, including (i) maps of tectonic strain (ii) maps of seismic hazard (iii) volcano deformation alerts. The accuracy of these products will improve as the number of data products acquired by Sentinel-1 increases, and as the time series lengthen. *http://comet.nerc.ac.uk**http://comet.nerc.ac.uk/COMET-LiCS-portal/

  8. Strategies for the implementation of a European Volcano Observations Research Infrastructure

    Science.gov (United States)

    Puglisi, Giuseppe

    2015-04-01

    Active volcanic areas in Europe constitute a direct threat to millions of people on both the continent and adjacent islands. Furthermore, eruptions of "European" volcanoes in overseas territories, such as in the West Indies, an in the Indian and Pacific oceans, can have a much broader impacts, outside Europe. Volcano Observatories (VO), which undertake volcano monitoring under governmental mandate and Volcanological Research Institutions (VRI; such as university departments, laboratories, etc.) manage networks on European volcanoes consisting of thousands of stations or sites where volcanological parameters are either continuously or periodically measured. These sites are equipped with instruments for geophysical (seismic, geodetic, gravimetric, electromagnetic), geochemical (volcanic plumes, fumaroles, groundwater, rivers, soils), environmental observations (e.g. meteorological and air quality parameters), including prototype deployment. VOs and VRIs also operate laboratories for sample analysis (rocks, gases, isotopes, etc.), near-real time analysis of space-borne data (SAR, thermal imagery, SO2 and ash), as well as high-performance computing centres; all providing high-quality information on the current status of European volcanoes and the geodynamic background of the surrounding areas. This large and high-quality deployment of monitoring systems, focused on a specific geophysical target (volcanoes), together with the wide volcanological phenomena of European volcanoes (which cover all the known volcano types) represent a unique opportunity to fundamentally improve the knowledge base of volcano behaviour. The existing arrangement of national infrastructures (i.e. VO and VRI) appears to be too fragmented to be considered as a unique distributed infrastructure. Therefore, the main effort planned in the framework of the EPOS-PP proposal is focused on the creation of services aimed at providing an improved and more efficient access to the volcanological facilities

  9. Long-Term Monitoring of the Impacts of Disaster on Human Activity Using DMSP/OLS Nighttime Light Data: A Case Study of the 2008 Wenchuan, China Earthquake

    Directory of Open Access Journals (Sweden)

    Xue Li

    2018-04-01

    Full Text Available Time series monitoring of earthquake-stricken areas is significant in evaluating post-disaster reconstruction and recovery. The time series of nighttime light (NTL data collected by the defense meteorological satellite program-operational linescan system (DMSP/OLS sensors provides a unique and valuable resource to study changes in human activity (HA because of the long period of available data. In this paper, the DMSP/OLS NTL images’ digital number (DN is used as a proxy for the intensity of HA since there is a high correlation between them. The purpose of this study is to develop a methodology to analyze the changes of intensity and distribution of HA in different areas affected by a 2008 earthquake in Wenchuan, China. In order to compare the trends of HA before and after the earthquake, the DMSP/OLS NTL images from 2003 to 2013 were processed and analyzed. However, their analysis capability is greatly limited owing to a lack of in-flight calibration. To improve the continuity and comparability of DMSP/OLS NTL images, this study developed an automatic intercalibration method to systematically correct NTL data. The results reveal that: (1 compared with the HA before the earthquake, the reconstruction and recovery of the Wenchuan earthquake have led to a significant increase of HA in earthquake-stricken areas within three years after the earthquake; (2 the fluctuation of HA in a severely-affected area is greater than that in a less-affected area; (3 recovery efforts increase development in the most affected areas to levels that exceeded the rates in similar areas which experienced less damage; and (4 areas alongside roads and close to reconstruction projects exhibited increased development in regions with otherwise low human activity.

  10. Impacts of Social Network on Therapeutic Community Participation: A Follow-up Survey of Data Gathered after Ya’an Earthquake

    Science.gov (United States)

    LI, Zhichao; CHEN, Yao; SUO, Liming

    2015-01-01

    Abstract Background In recent years, natural disasters and the accompanying health risks have become more frequent, and rehabilitation work has become an important part of government performance. On one hand, social networks play an important role in participants’ therapeutic community participation and physical & mental recovery. On the other hand, therapeutic communities with widespread participation can also contribute to community recovery after disaster. Methods This paper described a field study in an earthquake-stricken area of Ya’an. A set of 3-stage follow-up data was obtained concerning with the villagers’ participation in therapeutic community, social network status, demographic background, and other factors. The Hierarchical linear Model (HLM) method was used to investigate the determinants of social network on therapeutic community participation. Results First, social networks have significantly impacts on the annual changes of therapeutic community participation. Second, there were obvious differences in education between groups mobilized by the self-organization and local government. However, they all exerted the mobilization force through the acquaintance networks. Third, local cadre networks of villagers could negatively influence the activities of self-organized therapeutic community, while with positively influence in government-organized therapeutic activities. Conclusion This paper suggests that relevant government departments need to focus more on the reconstruction and cultivation of villagers’ social network and social capital in the process of post-disaster recovery. These findings contribute to better understandings of how social networks influence therapeutic community participation, and what role local government can play in post-disaster recovery and public health improvement after natural disasters. PMID:26060778

  11. Earthquake forecasting and warning

    Energy Technology Data Exchange (ETDEWEB)

    Rikitake, T.

    1983-01-01

    This review briefly describes two other books on the same subject either written or partially written by Rikitake. In this book, the status of earthquake prediction efforts in Japan, China, the Soviet Union, and the United States are updated. An overview of some of the organizational, legal, and societal aspects of earthquake prediction in these countries is presented, and scientific findings of precursory phenomena are included. A summary of circumstances surrounding the 1975 Haicheng earthquake, the 1978 Tangshan earthquake, and the 1976 Songpan-Pingwu earthquake (all magnitudes = 7.0) in China and the 1978 Izu-Oshima earthquake in Japan is presented. This book fails to comprehensively summarize recent advances in earthquake prediction research.

  12. Intensity earthquake scenario (scenario event - a damaging earthquake with higher probability of occurrence) for the city of Sofia

    Science.gov (United States)

    Aleksandrova, Irena; Simeonova, Stela; Solakov, Dimcho; Popova, Maria

    2014-05-01

    Among the many kinds of natural and man-made disasters, earthquakes dominate with regard to their social and economical impact on the urban environment. Global seismic risk to earthquakes are increasing steadily as urbanization and development occupy more areas that a prone to effects of strong earthquakes. Additionally, the uncontrolled growth of mega cities in highly seismic areas around the world is often associated with the construction of seismically unsafe buildings and infrastructures, and undertaken with an insufficient knowledge of the regional seismicity peculiarities and seismic hazard. The assessment of seismic hazard and generation of earthquake scenarios is the first link in the prevention chain and the first step in the evaluation of the seismic risk. The earthquake scenarios are intended as a basic input for developing detailed earthquake damage scenarios for the cities and can be used in earthquake-safe town and infrastructure planning. The city of Sofia is the capital of Bulgaria. It is situated in the centre of the Sofia area that is the most populated (the population is of more than 1.2 mil. inhabitants), industrial and cultural region of Bulgaria that faces considerable earthquake risk. The available historical documents prove the occurrence of destructive earthquakes during the 15th-18th centuries in the Sofia zone. In 19th century the city of Sofia has experienced two strong earthquakes: the 1818 earthquake with epicentral intensity I0=8-9 MSK and the 1858 earthquake with I0=9-10 MSK. During the 20th century the strongest event occurred in the vicinity of the city of Sofia is the 1917 earthquake with MS=5.3 (I0=7-8 MSK). Almost a century later (95 years) an earthquake of moment magnitude 5.6 (I0=7-8 MSK) hit the city of Sofia, on May 22nd, 2012. In the present study as a deterministic scenario event is considered a damaging earthquake with higher probability of occurrence that could affect the city with intensity less than or equal to VIII

  13. Spatio-temporal evolution of volcano seismicity: A laboratory study

    Science.gov (United States)

    Benson, Philip M.; Vinciguerra, Sergio; Meredith, Philip G.; Young, R. Paul

    2010-08-01

    We report a laboratory and microstructural study of a suite of deformation experiments in which basalt from Mount Etna volcano is deformed and fractured at an effective confining pressure representative of conditions under a volcanic edifice (40 MPa). Particular attention was paid to the formation of a fracture and damage zone with which to stimulate coupled hydro-mechanical interactions that create the various types of seismicity recorded on volcanic edifices, and which usually precede eruption. Location of AE events through time shows the formation of a fault plane during which waveforms exhibit the typical high frequency characteristics of volcano-tectonic (VT) earthquakes. We found that these VT earthquakes were particularly pronounced when generated using dry samples, compared to samples saturated with a pore fluid (water). VT events generated during deformation of water saturated sample are characterised by a distinctive high frequency onset and a longer, low frequency coda exhibiting properties often seen in the field as hybrid events. We present evidence that hybrid events are, in fact, the common type of volcanic seismic event with either VT or low frequency (LF) events representing end members, and whose proportion depend on pore fluid being present in the rock type being deformed, as well as how close the rock is to failure. We find a notable trend of reducing instances of hybrid events leading up to the failure stage in our experiments, suggesting that during this stage, the pore fluid present in the rock moves sufficiently quickly to provide a resonance, seen as a LF coda. Our data supports recent modeling and field studies that postulate that hybrid events generated in volcanic areas are likely to be generated through the interaction of hydrothermal fluids moving through a combination of pre-existing microcrack networks and larger faults, such as those we observe in forensic (post-test) examination.

  14. Some Recent USF Studies at Volcanoes in Central America

    Science.gov (United States)

    McNutt, S. R.

    2014-12-01

    Scientists at the University of South Florida (USF) have been working in Central America for several decades. Efforts have focused on Physical Volcanology in Nicaragua, GPS in Costa Rica, and assessment of Geothermal projects in El Salvador, amongst others. Two years ago a Seismology Lab was established at USF. Personnel now include three Professors, a Post-Doc, and 4 graduate students. Seismic and GPS networks were installed at Telica Volcano, Nicaragua, in 2010 by Roman, LaFemina and colleagues. Data are recorded on site and recovered several times per year at this persistently restless volcano, which has rates of 5 to 1400 low frequency seismic events per day (Rodgers et al., submitted). Proposals have been submitted to install instruments on other Nicaraguan volcanoes, including seismometers, GPS, infrasound, and lightning sensors. This suite of instruments has proven to be very effective to study a range of volcanic processes. The proposals have not been successful to date (some are pending), and alternative funding sources are being explored. One interesting scientific issue is the presence of strong seasonal effects, specifically a pronounced rainy season and dry season and possible interaction between shallow volcanic processes and surface waters. We are also pursuing a variety of studies that are complementary to the instrumental efforts. One such study is examining volcanic earthquake swarms, with the focus to date on identifying diagnostics. One clear pattern is that peak rates often occur early in swarms, whereas the largest M event occurs late. Additional evidence suggests that the seismic source size grows systematically, especially for events with similar waveforms (families). Recognition of such patterns, linked to processes, may help to improve monitoring and better take advantage of instrumental data to reduce vulnerability from eruptions.

  15. Aleutian Islands Coastal Resources Inventory and Environmental Sensitivity Maps: VOLCANOS (Volcano Points)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This data set contains point locations of active volcanoes as compiled by Motyka et al., 1993. Eighty-nine volcanoes with eruptive phases in the Quaternary are...

  16. Deep geological strucure of a volcano verified by seismic wave. Jishinha de mita kazan no shinbu kozo

    Energy Technology Data Exchange (ETDEWEB)

    Hasegawa, A. (Tohoku University, Sendai (Japan). Faculty of Science)

    1991-09-01

    Three dimensional structure of seismic wave velocity for the crest and upper mantle under the North East Japan is determined by the seismic tomography which is prepared by the natural earthquakes confirmed by the observation network for micro earthquakes, indicating that the low velocity region exists just under the corresponding volcano to the upper mantle. Further, the following contents can be verified: Any micro earthquakes which are verified by the above observation network and occur at the depth of 25-40km show the lower generation rate less than 1% and the low dominant frequency compared with the conventional inland earthquake(lower limit of depth is 15km) in the same region and occur around volcanos. The existence of the remarkable reflection surface for S wave which is found at the depth of 10-20km seems to be caused by the melting mass. The above mentioned low velocity region is estimated to correspond to the lifting region of high temperature magma, micro earthquakes of low frequency to the magma activity around that magma and the reflection surface for S wave to the part of the magma. 8 refs., 4 figs.

  17. A discussion of the socio-economic losses and shelter impacts from the Van, Turkey Earthquakes of October and November 2011

    Science.gov (United States)

    Daniell, J. E.; Khazai, B.; Wenzel, F.; Kunz-Plapp, T.; Vervaeck, A.; Muehr, B.; Markus, M.

    2012-04-01

    The Van earthquake in 2011 hit at 10:41 GMT (13:41 Local) on Sunday, October 23rd, 2011. It was a Mw7.1-7.3 event located at a depth of around 10 km with the epicentre located directly between Ercis (pop. 75,000) and Van (pop. 370,000). Since then, the CEDIM Forensic Analysis Group (using a team of seismologists, engineers, sociologists and meteorologists) and www.earthquake-report.com has reported and analysed on the Van event. In addition, many damaging aftershocks occurring after the main eventwere analysed including a major aftershock centered in Van-Edremit on November 9th, 2011, causing much additional losses. The province of Van has around 1.035 million people as of the last census. The Van province is one of the poorest in Turkey and has much inequality between the rural and urban centers with an average HDI (Human Development Index) around that of Bhutan or Congo. The earthquakes are estimated to have caused 604 deaths (23 October) and 40 deaths (9 November); mostly due to falling debris and house collapse). In addition, between 1 billion TRY to 4 billion TRY (approx. 555 million USD - 2.2 billion USD) is estimated as total economic losses. This represents around 17 to 66% of the provincial GDP of the Van Province (approx. 3.3 billion USD) as of 2011. From the CATDAT Damaging Earthquakes Database, major earthquakes such as this one have occurred in the year 1111 causing major damage and having a magnitude around 6.5-7. In the year 1646 or 1648, Van was again struck by a M6.7 quake killing around 2000 people. In 1881, a M6.3 earthquake near Van killed 95 people. Again, in 1941, a M5.9 earthquake affected Ercis and Van killing between 190 and 430 people. 1945-1946 as well as 1972 brought again damaging and casualty-bearing earthquakes to the Van province. In 1976, the Van-Muradiye earthquake struck the border region with a M7, killing around 3840 people and causing around 51,000 people to become homeless. Key immediate lessons from similar historic

  18. Flank tectonics of Martian volcanoes

    International Nuclear Information System (INIS)

    Thomas, P.J.; Squyres, S.W.; Carr, M.H.

    1990-01-01

    On the flanks of Olympus Mons is a series of terraces, concentrically distributed around the caldera. Their morphology and location suggest that they could be thrust faults caused by compressional failure of the cone. In an attempt to understand the mechanism of faulting and the possible influences of the interior structure of Olympus Mons, the authors have constructed a numerical model for elastic stresses within a Martian volcano. In the absence of internal pressurization, the middle slopes of the cone are subjected to compressional stress, appropriate to the formation of thrust faults. These stresses for Olympus Mons are ∼250 MPa. If a vacant magma chamber is contained within the cone, the region of maximum compressional stress is extended toward the base of the cone. If the magma chamber is pressurized, extensional stresses occur at the summit and on the upper slopes of the cone. For a filled but unpressurized magma chamber, the observed positions of the faults agree well with the calculated region of high compressional stress. Three other volcanoes on Mars, Ascraeus Mons, Arsia Mons, and Pavonis Mons, possess similar terraces. Extending the analysis to other Martian volcanoes, they find that only these three and Olympus Mons have flank stresses that exceed the compressional failure strength of basalt, lending support to the view that the terraces on all four are thrust faults

  19. Environmental impact of CO2, Rn, Hg degassing from the rupture zones produced by Wenchuan M s 8.0 earthquake in western Sichuan, China.

    Science.gov (United States)

    Zhou, Xiaocheng; Chen, Zhi; Cui, Yueju

    2016-10-01

    The concentrations and flux of CO2, (222)Radon (Rn), and gaseous elemental mercury (Hg) in soil gas were investigated based on the field measurements in June 2010 at ten sites along the seismic rupture zones produced by the May 12, 2008, Wenchuan M s 8.0 earthquake in order to assess the environmental impact of degassing of CO2, Rn and Hg. Soil gas concentrations of 344 sampling points were obtained. Seventy measurements of CO2, Rn and Hg flux by the static accumulation chamber method were performed. The results of risk assessment of CO2, Rn and Hg concentration in soil gas showed that (1) the concentration of CO2 in the epicenter of Wenchuan M s 8.0 earthquake and north end of seismic ruptures had low risk of asphyxia; (2) the concentrations of Rn in the north segment of seismic ruptures had high levels of radon, Maximum was up to level 4, according to Chinese code (GB 50325-2001); (3) the average geoaccumulation index I geo of soil Hg denoted the lack of soil contamination, and maximum values classified the soil gas as moderately to strongly polluted in the epicenter. The investigation of soil gas CO2, Rn and Hg degassing rate indicated that (1) the CO2 in soil gas was characterized by a mean [Formula: see text] of -20.4 ‰ and by a mean CO2 flux of 88.1 g m(-2) day(-1), which were in the range of the typical values for biologic CO2 degassing. The maximum of soil CO2 flux reached values of 399 g m(-2) day(-1) in the epicenter; (2) the soil Rn had higher exhalation in the north segment of seismic ruptures, the maximum reached value of 1976 m Bq m(-2) s(-1); (3) the soil Hg flux was lower, ranging from -2.5 to 18.7 n g m(-2) h(-1) and increased from south to north. The mean flux over the all profiles was 4.2 n g m(-2) h(-1). The total output of CO2 and Hg degassing estimated along seismic ruptures for a survey area of 18.17 km(2) were approximately 0.57 Mt year(-1) and 688.19 g year(-1). It is recommended that land-use planners should

  20. The Hawaiian Volcano Observatory: a natural laboratory for studying basaltic volcanism: Chapter 1 in Characteristics of Hawaiian volcanoes

    Science.gov (United States)

    Tilling, Robert I.; Kauahikaua, James P.; Brantley, Steven R.; Neal, Christina A.; Poland, Michael P.; Takahashi, T. Jane; Landowski, Claire M.

    2014-01-01

    In the beginning of the 20th century, geologist Thomas A. Jaggar, Jr., argued that, to fully understand volcanic and associated hazards, the expeditionary mode of studying eruptions only after they occurred was inadequate. Instead, he fervently advocated the use of permanent observatories to record and measure volcanic phenomena—at and below the surface—before, during, and after eruptions to obtain the basic scientific information needed to protect people and property from volcanic hazards. With the crucial early help of American volcanologist Frank Alvord Perret and the Hawaiian business community, the Hawaiian Volcano Observatory (HVO) was established in 1912, and Jaggar’s vision became reality. From its inception, HVO’s mission has centered on several goals: (1) measuring and documenting the seismic, eruptive, and geodetic processes of active Hawaiian volcanoes (principally Kīlauea and Mauna Loa); (2) geological mapping and dating of deposits to reconstruct volcanic histories, understand island evolution, and determine eruptive frequencies and volcanic hazards; (3) systematically collecting eruptive products, including gases, for laboratory analysis; and (4) widely disseminating observatory-acquired data and analysis, reports, and hazard warnings to the global scientific community, emergency-management authorities, news media, and the public. The long-term focus on these goals by HVO scientists, in collaboration with investigators from many other organizations, continues to fulfill Jaggar’s career-long vision of reducing risks from volcanic and earthquake hazards across the globe.

  1. Shallow moonquakes - How they compare with earthquakes

    Science.gov (United States)

    Nakamura, Y.

    1980-01-01

    Of three types of moonquakes strong enough to be detectable at large distances - deep moonquakes, meteoroid impacts and shallow moonquakes - only shallow moonquakes are similar in nature to earthquakes. A comparison of various characteristics of moonquakes with those of earthquakes indeed shows a remarkable similarity between shallow moonquakes and intraplate earthquakes: (1) their occurrences are not controlled by tides; (2) they appear to occur in locations where there is evidence of structural weaknesses; (3) the relative abundances of small and large quakes (b-values) are similar, suggesting similar mechanisms; and (4) even the levels of activity may be close. The shallow moonquakes may be quite comparable in nature to intraplate earthquakes, and they may be of similar origin.

  2. Geophysical research on structure of partly eroded maar volcanoes: Miocene Hnojnice and Oligocene Rychnov volcanoes (northern Czech Republic)

    Czech Academy of Sciences Publication Activity Database

    Skácelová, Z.; Rapprich, V.; Valenta, Jan; Hartvich, Filip; Šrámek, J.; Radoň, M.; Gaždová, Renata; Nováková, Lucie; Kolínský, Petr; Pécskay, Z.

    2010-01-01

    Roč. 55, č. 4 (2010), s. 299-310 ISSN 1802-6222 R&D Projects: GA AV ČR IAA300460602 Institutional research plan: CEZ:AV0Z30460519 Keywords : maar–diatreme volcano * ground magnetometry * ground gravity measurements Subject RIV: DC - Siesmology, Volcanology, Earth Structure Impact factor: 1.026, year: 2010 www.jgeosci.org/content/jgeosci.072_2010_4_skacelova.pdf

  3. Tracking hydrothermal feature changes in response to seismicity and deformation at Mud Volcano thermal area, Yellowstone

    Science.gov (United States)

    Diefenbach, A. K.; Hurwitz, S.; Murphy, F.; Evans, W.

    2013-12-01

    The Mud Volcano thermal area in Yellowstone National Park comprises many hydrothermal features including fumaroles, mudpots, springs, and thermal pools. Observations of hydrothermal changes have been made for decades in the Mud Volcano thermal area, and include reports of significant changes (the appearance of new features, increased water levels in pools, vigor of activity, and tree mortality) following an earthquake swarm in 1978 that took place beneath the area. However, no quantitative method to map and measure surface feature changes through time has been applied. We present an analysis of aerial photographs from 1954 to present to track temporal changes in the boundaries between vegetated and thermally barren areas, as well as location, extent, color, clarity, and runoff patterns of hydrothermal features within the Mud Volcano thermal area. This study attempts to provide a detailed, long-term (>50 year) inventory of hydrothermal features and change detection at Mud Volcano thermal area that can be used to identify changes in hydrothermal activity in response to seismicity, uplift and subsidence episodes of the adjacent Sour Creek resurgent dome, or other potential causes.

  4. Evaluation of landslide susceptibility of Sete Cidades Volcano (S. Miguel Island, Azores

    Directory of Open Access Journals (Sweden)

    A. Gomes

    2005-01-01

    Full Text Available Sete Cidades is an active central volcano with a summit caldera located in the westernmost part of S. Miguel Island (Azores. Since the settlement of the Island, in the 15th century, many landslide events occurred in this volcano, causing extensive damages in buildings and infrastructures. The study of historical records and the observation of new occurrences showed that landslides in the region have been triggered by heavy rainfall periods, earthquakes and erosion. In order to assess landslide susceptibility at Sete Cidades Volcano, landslide scars and associated deposits were mapped through aerial photographs and field surveys. The obtained data were inserted in a GIS to produce a landslide distribution map. It was concluded that the high density landslide areas are related with (1 major scarp faults, (2 the margin of fluvial channels, (3 the sea cliffs and (4 volcanic landforms, namely the caldera wall. About 73% of the mapped events took place in areas where pyroclastic deposits are the dominant lithology and more than 77% occurred where slopes are equal or higher than 20°. These two parameters were integrated and used to generate a preliminary susceptibility map. The incorporation of vulnerability data into the GIS allowed concluding that 30% of dwellings and most of the roads on Sete Cidades Volcano are located in areas where landslide susceptibility is high to very high. Such conclusion should be taken into account for emergency and land use planning.

  5. Encyclopedia of earthquake engineering

    CERN Document Server

    Kougioumtzoglou, Ioannis; Patelli, Edoardo; Au, Siu-Kui

    2015-01-01

    The Encyclopedia of Earthquake Engineering is designed to be the authoritative and comprehensive reference covering all major aspects of the science of earthquake engineering, specifically focusing on the interaction between earthquakes and infrastructure. The encyclopedia comprises approximately 265 contributions. Since earthquake engineering deals with the interaction between earthquake disturbances and the built infrastructure, the emphasis is on basic design processes important to both non-specialists and engineers so that readers become suitably well-informed without needing to deal with the details of specialist understanding. The content of this encyclopedia provides technically inclined and informed readers about the ways in which earthquakes can affect our infrastructure and how engineers would go about designing against, mitigating and remediating these effects. The coverage ranges from buildings, foundations, underground construction, lifelines and bridges, roads, embankments and slopes. The encycl...

  6. Earthquake at 40 feet

    Science.gov (United States)

    Miller, G. J.

    1976-01-01

    The earthquake that struck the island of Guam on November 1, 1975, at 11:17 a.m had many unique aspects-not the least of which was the experience of an earthquake of 6.25 Richter magnitude while at 40 feet. My wife Bonnie, a fellow diver, Greg Guzman, and I were diving at Gabgab Beach in teh outer harbor of Apra Harbor, engaged in underwater phoyography when the earthquake struck. 

  7. Earthquakes and economic growth

    OpenAIRE

    Fisker, Peter Simonsen

    2012-01-01

    This study explores the economic consequences of earthquakes. In particular, it is investigated how exposure to earthquakes affects economic growth both across and within countries. The key result of the empirical analysis is that while there are no observable effects at the country level, earthquake exposure significantly decreases 5-year economic growth at the local level. Areas at lower stages of economic development suffer harder in terms of economic growth than richer areas. In addition,...

  8. The Northern Rupture of the 1762 Arakan Meghathrust Earthquake and other Potential Earthquake Sources in Bangladesh.

    Science.gov (United States)

    Akhter, S. H.; Seeber, L.; Steckler, M. S.

    2015-12-01

    Bangladesh is one of the most densely populated countries in the world. It occupies a major part of the Bengal Basin, which contains the Ganges-Brahmaputra Delta (GBD), the largest and one of the most active of world deltas, and is located along the Alpine-Himalayan seismic belt. As such it is vulnerable to many natural hazards, especially earthquakes. The country sits at the junction of three tectonic plates - Indian, Eurasian, and the Burma 'sliver' of the Sunda plate. These form two boundaries where plates converge- the India-Eurasia plate boundary to the north forming the Himalaya Arc and the India-Burma plate boundary to the east forming the Indo-Burma Arc. The India-Burma plate boundary is exceptionally wide because collision with the GBD feeds an exception amount of sediment into the subduction zone. Thus the Himalayan continent collision orogeny along with its syntaxes to the N and NE of Bangladesh and the Burma Arc subduction boundary surround Bangladesh on two sides with active faults of regional scale, raising the potential for high-magnitude earthquakes. In recent years Bangladesh has experienced minor to moderate earthquakes. Historical records show that major and great earthquakes have ravaged the country and the neighboring region several times over the last 450 years. Field observations of Tertiary structures along the Chittagong-Teknaf coast reveal that the rupture of 1762 Arakan megathrust earthquake extended as far north as the Sitakund anticline to the north of the city of Chittagong. This earthquake brought changes to the landscape, uplifting the Teknaf peninsula and St. Martin's Island by about 2-2.5 m, and activated two mud volcanos along the axis of the Sitakund anticline, where large tabular blocks of exotic crystalline limestone, were tectonically transported from a deep-seated formation along with the eruptive mud. Vast area of the coast including inland areas east of the lower Meghna River were inundated. More than 500 peoples died near

  9. Antarctic volcanoes: A remote but significant hazard

    Science.gov (United States)

    Geyer, Adelina; Martí, Alex; Folch, Arnau; Giralt, Santiago

    2017-04-01

    Ash emitted during explosive volcanic eruptions can be dispersed over massive areas of the globe, posing a threat to both human health and infrastructures, such as the air traffic. Some of the last eruptions occurred during this decade (e.g. 14/04/2010 - Eyjafjallajökull, Iceland; 24/05/2011-Grímsvötn, Iceland; 05/06/2011-Puyehue-Cordón Caulle, Chile) have strongly affected the air traffic in different areas of the world, leading to economic losses of billions of euros. From the tens of volcanoes located in Antarctica, at least nine are known to be active and five of them have reported volcanic activity in historical times. However, until now, no attention has been paid to the possible social, economical and environmental consequences of an eruption that would occur on high southern latitudes, perhaps because it is considered that its impacts would be minor or local, and mainly restricted to the practically inhabited Antarctic continent. We show here, as a case study and using climate models, how volcanic ash emitted during a regular eruption of one of the most active volcanoes in Antarctica, Deception Island (South Shetland Islands), could reach the African continent as well as Australia and South America. The volcanic cloud could strongly affect the air traffic not only in the region and at high southern latitudes, but also the flights connecting Africa, South America and Oceania. Results obtained are crucial to understand the patterns of volcanic ash distribution at high southern latitudes with obvious implications for tephrostratigraphical and chronological studies that provide valuable isochrones with which to synchronize palaeoclimate records. This research was partially funded by the MINECO grants VOLCLIMA (CGL2015-72629-EXP)and POSVOLDEC(CTM2016-79617-P)(AEI/FEDER, UE), the Ramón y Cajal research program (RYC-2012-11024) and the NEMOH European project (REA grant 34 agreement n° 289976).

  10. Earthquake engineering development before and after the March 4, 1977, Vrancea, Romania earthquake

    International Nuclear Information System (INIS)

    Georgescu, E.-S.

    2002-01-01

    At 25 years since the of the Vrancea earthquake of March, 4th 1977, we can analyze in an open and critical way its impact on the evolution of earthquake engineering codes and protection policies in Romania. The earthquake (M G-R = 7.2; M w = 7.5), produced 1,570 casualties and more than 11,300 injured persons (90% of the victims in Bucharest), seismic losses were estimated at more then USD 2 billions. The 1977 earthquake represented a significant episode of XXth century in seismic zones of Romania and neighboring countries. The INCERC seismic record of March 4, 1977 put, for the first time, in evidence the spectral content of long period seismic motions of Vrancea earthquakes, the duration, the number of cycles and values of actual accelerations, with important effects of overloading upon flexible structures. The seismic coefficients k s , the spectral curve (the dynamic coefficient β r ) and the seismic zonation map, the requirements in the antiseismic design norms were drastically, changed while the microzonation maps of the time ceased to be used, and the specific Vrancea earthquake recurrence was reconsidered based on hazard studies Thus, the paper emphasises: - the existing engineering knowledge, earthquake code and zoning maps requirements until 1977 as well as seismology and structural lessons since 1977; - recent aspects of implementing of the Earthquake Code P.100/1992 and harmonization with Eurocodes, in conjunction with the specific of urban and rural seismic risk and enforcing policies on strengthening of existing buildings; - a strategic view of disaster prevention, using earthquake scenarios and loss assessments, insurance, earthquake education and training; - the need of a closer transfer of knowledge between seismologists, engineers and officials in charge with disaster prevention public policies. (author)

  11. K-Ar ages of the Hiruzen volcano group and the Daisen volcano

    International Nuclear Information System (INIS)

    Tsukui, Masashi; Nishido, Hirotsugu; Nagao, Keisuke.

    1985-01-01

    Seventeen volcanic rocks of the Hiruzen volcano group and the Daisen volcano, in southwest Japan, were dated by the K-Ar method to clarify the age of volcanic activity in this region and the evolution of these composite volcanoes. The eruption ages of the Hiruzen volcano group were revealed to be about 0.9 Ma to 0.5 Ma, those of the Daisen volcano to be about 1 Ma to very recent. These results are consistent with geological and paleomagnetic data of previous workers. Effusion of lavas in the area was especially vigorous at 0.5+-0.1 Ma. It was generally considered that the Hiruzen volcano group had erupted during latest Pliocene to early Quaternary and it is older than the Daisen volcano, mainly from their topographic features. However, their overlapping eruption ages and petrographical similarities of the lavas of the Hiruzen volcano group and the Daisen volcano suggest that they may be included in the Daisen volcano in a broad sense. The aphyric andesite, whose eruption age had been correlated to Wakurayama andesite (6.34+-0.19 Ma) in Matsue city and thought to be the basement of the Daisen volcano, was dated to be 0.46+-0.04 Ma. It indicates that petrographically similar aphyric andesite erupted sporadically at different time and space in the San'in district. (author)

  12. Earthquakes, Cities, and Lifelines: lessons integrating tectonics, society, and engineering in middle school Earth Science

    Science.gov (United States)

    Toke, N.; Johnson, A.; Nelson, K.

    2010-12-01

    Earthquakes are one of the most widely covered geologic processes by the media. As a result students, even at the middle school level, arrive in the classroom with preconceptions about the importance and hazards posed by earthquakes. Therefore earthquakes represent not only an attractive topic to engage students when introducing tectonics, but also a means to help students understand the relationships between geologic processes, society, and engineering solutions. Facilitating understanding of the fundamental connections between science and society is important for the preparation of future scientists and engineers as well as informed citizens. Here, we present a week-long lesson designed to be implemented in five one hour sessions with classes of ~30 students. It consists of two inquiry-based mapping investigations, motivational presentations, and short readings that describe fundamental models of plate tectonics, faults, and earthquakes. The readings also provide examples of engineering solutions such as the Alaskan oil pipeline which withstood multi-meter surface offset in the 2002 Denali Earthquake. The first inquiry-based investigation is a lesson on tectonic plates. Working in small groups, each group receives a different world map plotting both topography and one of the following data sets: GPS plate motion vectors, the locations and types of volcanoes, the location of types of earthquakes. Using these maps and an accompanying explanation of the data each group’s task is to map plate boundary locations. Each group then presents a ~10 minute summary of the type of data they used and their interpretation of the tectonic plates with a poster and their mapping results. Finally, the instructor will facilitate a class discussion about how the data types could be combined to understand more about plate boundaries. Using student interpretations of real data allows student misconceptions to become apparent. Throughout the exercise we record student preconceptions

  13. Development of evaluation methods for impact of earthquake-induced slope failure on nearby critical structures. Analysis of behavior of collapsed rock masses using 3-D distinct element method

    International Nuclear Information System (INIS)

    Ishimaru, Makoto; Tochigi, Hitoshi; Nakajima, Masato; Shirai, Koji

    2012-01-01

    Recently, importance of evaluation for impact of earthquake-induced slope failure on nearby critical structures is increasing in order to evaluate seismic stability of the slope, in addition to evaluating the possibilities of slope failure. In this study, we presented an examination flow chart to evaluate the impact on structures after slope failure. In the examination flow chart, we assumed the following four considerations; (1) evaluation of the collapse region of the slope, (2) evaluation of behavior of the collapsed rock masses, (3) evaluation of the impact on the structures, (4) examination of the countermeasures. And, for the purpose of using three dimensional distinct element method (DEM) for evaluation of behavior of the collapsed rock masses, we firstly confirmed applicability of DEM to behavior of a mass hurtling down the slope by means of comparing with the model test results. Moreover, we clarified influence of initial position or restitution coefficient of rock masses on final traveling distance of collapsed rock masses. (author)

  14. The earthquake/seismic risk, vulnerability and capacity profile for ...

    African Journals Online (AJOL)

    The study was carried out to understand the risks posed by earthquakes in Karonga based on roles and perception of stakeholders. Information was collected from several stakeholders who were found responding to earthquakes impacts in Karonga Town. The study found that several stakeholders, governmental and ...

  15. Weak tidal correlation of NW-Bohemia/Vogtland earthquake swarms

    Czech Academy of Sciences Publication Activity Database

    Fischer, Tomáš; Kalenda, Pavel; Skalský, Lumír

    2006-01-01

    Roč. 424, č. 3-4 (2006), s. 259-269 ISSN 0040-1951 R&D Projects: GA AV ČR IAA3012308 Institutional research plan: CEZ:AV0Z30460519 Keywords : Earth tides * earthquake swarm * triggered earthquakes Subject RIV: DC - Siesmology, Volcanology, Earth Structure Impact factor: 1.675, year: 2006

  16. Weak tidal correlation of NW-Bohemia/Vogtland earthquake swarms

    Czech Academy of Sciences Publication Activity Database

    Fischer, Tomáš; Kalenda, Pavel; Skalský, Lumír

    2006-01-01

    Roč. 424, č. 3-4 (2006), s. 259-269 ISSN 0040-1951 R&D Projects: GA AV ČR IAA3012308 Institutional research plan: CEZ:AV0Z30120515; CEZ:AV0Z30460519 Keywords : Earth tides * earthquake swarm * triggered earthquakes Subject RIV: DC - Siesmology, Volcanology, Earth Structure Impact factor: 1.675, year: 2006

  17. Modelling the elements of country vulnerability to earthquake disasters.

    Science.gov (United States)

    Asef, M R

    2008-09-01

    Earthquakes have probably been the most deadly form of natural disaster in the past century. Diversity of earthquake specifications in terms of magnitude, intensity and frequency at the semicontinental scale has initiated various kinds of disasters at a regional scale. Additionally, diverse characteristics of countries in terms of population size, disaster preparedness, economic strength and building construction development often causes an earthquake of a certain characteristic to have different impacts on the affected region. This research focuses on the appropriate criteria for identifying the severity of major earthquake disasters based on some key observed symptoms. Accordingly, the article presents a methodology for identification and relative quantification of severity of earthquake disasters. This has led to an earthquake disaster vulnerability model at the country scale. Data analysis based on this model suggested a quantitative, comparative and meaningful interpretation of the vulnerability of concerned countries, and successfully explained which countries are more vulnerable to major disasters.

  18. Geoflicks Reviewed--Films about Hawaiian Volcanoes.

    Science.gov (United States)

    Bykerk-Kauffman, Ann

    1994-01-01

    Reviews 11 films on volcanic eruptions in the United States. Films are given a one- to five-star rating and the film's year, length, source and price are listed. Top films include "Inside Hawaiian Volcanoes" and "Kilauea: Close up of an Active Volcano." (AIM)

  19. Orographic Flow over an Active Volcano

    Science.gov (United States)

    Poulidis, Alexandros-Panagiotis; Renfrew, Ian; Matthews, Adrian

    2014-05-01

    Orographic flows over and around an isolated volcano are studied through a series of numerical model experiments. The volcano top has a heated surface, so can be thought of as "active" but not erupting. A series of simulations with different atmospheric conditions and using both idealised and realistic configurations of the Weather Research and Forecast (WRF) model have been carried out. The study is based on the Soufriere Hills volcano, located on the island of Montserrat in the Caribbean. This is a dome-building volcano, leading to a sharp increase in the surface skin temperature at the top of the volcano - up to tens of degrees higher than ambient values. The majority of the simulations use an idealised topography, in order for the results to have general applicability to similar-sized volcanoes located in the tropics. The model is initialised with idealised atmospheric soundings, representative of qualitatively different atmospheric conditions from the rainy season in the tropics. The simulations reveal significant changes to the orographic flow response, depending upon the size of the temperature anomaly and the atmospheric conditions. The flow regime and characteristic features such as gravity waves, orographic clouds and orographic rainfall patterns can all be qualitatively changed by the surface heating anomaly. Orographic rainfall over the volcano can be significantly enhanced with increased temperature anomaly. The implications for the eruptive behaviour of the volcano and resulting secondary volcanic hazards will also be discussed.

  20. OMG Earthquake! Can Twitter improve earthquake response?

    Science.gov (United States)

    Earle, P. S.; Guy, M.; Ostrum, C.; Horvath, S.; Buckmaster, R. A.

    2009-12-01

    The U.S. Geological Survey (USGS) is investigating how the social networking site Twitter, a popular service for sending and receiving short, public, text messages, can augment its earthquake response products and the delivery of hazard information. The goal is to gather near real-time, earthquake-related messages (tweets) and provide geo-located earthquake detections and rough maps of the corresponding felt areas. Twitter and other social Internet technologies are providing the general public with anecdotal earthquake hazard information before scientific information has been published from authoritative sources. People local to an event often publish information within seconds via these technologies. In contrast, depending on the location of the earthquake, scientific alerts take between 2 to 20 minutes. Examining the tweets following the March 30, 2009, M4.3 Morgan Hill earthquake shows it is possible (in some cases) to rapidly detect and map the felt area of an earthquake using Twitter responses. Within a minute of the earthquake, the frequency of “earthquake” tweets rose above the background level of less than 1 per hour to about 150 per minute. Using the tweets submitted in the first minute, a rough map of the felt area can be obtained by plotting the tweet locations. Mapping the tweets from the first six minutes shows observations extending from Monterey to Sacramento, similar to the perceived shaking region mapped by the USGS “Did You Feel It” system. The tweets submitted after the earthquake also provided (very) short first-impression narratives from people who experienced the shaking. Accurately assessing the potential and robustness of a Twitter-based system is difficult because only tweets spanning the previous seven days can be searched, making a historical study impossible. We have, however, been archiving tweets for several months, and it is clear that significant limitations do exist. The main drawback is the lack of quantitative information

  1. Mechanism of High Frequency Shallow Earthquake Source in Mount Soputan, North Sulawesi

    Directory of Open Access Journals (Sweden)

    Yasa Suparman

    2014-06-01

    Full Text Available DOI: 10.17014/ijog.v6i3.122Moment tensor analysis had been conducted to understand the source mechanism of earthquakes in Soputan Volcano during October - November 2010 period. The record shows shallow earthquakes with frequency about 5 - 9 Hz. Polarity distribution of P-wave first onset indicates that the recorded earthquakes are predominated by earthquakes where almost at all stations have the same direction of P-wave first motions, and earthquakes with upward first motions.In this article, the source mechanism is described as the second derivative of moment tensor, approached with first motion amplitude inversion of P-wave at some seismic stations. The result of moment tensor decomposition are predominated by earthquakes with big percentage in ISO and CLVD component. Focal mechanism shows that the recorded earthquakes have the same strike in northeast-southwest direction with dip about 400 - 600. The sources of the high frequency shallow earthquakes are in the form of tensile-shear cracks or a combination between crack and tensile faulting.

  2. Earthquakes trigger the loss of groundwater biodiversity

    Science.gov (United States)

    Galassi, Diana M. P.; Lombardo, Paola; Fiasca, Barbara; di Cioccio, Alessia; di Lorenzo, Tiziana; Petitta, Marco; di Carlo, Piero

    2014-09-01

    Earthquakes are among the most destructive natural events. The 6 April 2009, 6.3-Mw earthquake in L'Aquila (Italy) markedly altered the karstic Gran Sasso Aquifer (GSA) hydrogeology and geochemistry. The GSA groundwater invertebrate community is mainly comprised of small-bodied, colourless, blind microcrustaceans. We compared abiotic and biotic data from two pre-earthquake and one post-earthquake complete but non-contiguous hydrological years to investigate the effects of the 2009 earthquake on the dominant copepod component of the obligate groundwater fauna. Our results suggest that the massive earthquake-induced aquifer strain biotriggered a flushing of groundwater fauna, with a dramatic decrease in subterranean species abundance. Population turnover rates appeared to have crashed, no longer replenishing the long-standing communities from aquifer fractures, and the aquifer became almost totally deprived of animal life. Groundwater communities are notorious for their low resilience. Therefore, any major disturbance that negatively impacts survival or reproduction may lead to local extinction of species, most of them being the only survivors of phylogenetic lineages extinct at the Earth surface. Given the ecological key role played by the subterranean fauna as decomposers of organic matter and ``ecosystem engineers'', we urge more detailed, long-term studies on the effect of major disturbances to groundwater ecosystems.

  3. Volcano monitoring using GPS: Developing data analysis strategies based on the June 2007 Kīlauea Volcano intrusion and eruption

    Science.gov (United States)

    Larson, Kristine M.; Poland, Michael; Miklius, Asta

    2010-01-01

    The global positioning system (GPS) is one of the most common techniques, and the current state of the art, used to monitor volcano deformation. In addition to slow (several centimeters per year) displacement rates, GPS can be used to study eruptions and intrusions that result in much larger (tens of centimeters over hours-days) displacements. It is challenging to resolve precise positions using GPS at subdaily time intervals because of error sources such as multipath and atmospheric refraction. In this paper, the impact of errors due to multipath and atmospheric refraction at subdaily periods is examined using data from the GPS network on Kīlauea Volcano, Hawai'i. Methods for filtering position estimates to enhance precision are both simulated and tested on data collected during the June 2007 intrusion and eruption. Comparisons with tiltmeter records show that GPS instruments can precisely recover the timing of the activity.

  4. The Christchurch earthquake stroke incidence study.

    Science.gov (United States)

    Wu, Teddy Y; Cheung, Jeanette; Cole, David; Fink, John N

    2014-03-01

    We examined the impact of major earthquakes on acute stroke admissions by a retrospective review of stroke admissions in the 6 weeks following the 4 September 2010 and 22 February 2011 earthquakes. The control period was the corresponding 6 weeks in the previous year. In the 6 weeks following the September 2010 earthquake there were 97 acute stroke admissions, with 79 (81.4%) ischaemic infarctions. This was similar to the 2009 control period which had 104 acute stroke admissions, of whom 80 (76.9%) had ischaemic infarction. In the 6 weeks following the February 2011 earthquake, there were 71 stroke admissions, and 61 (79.2%) were ischaemic infarction. This was less than the 96 strokes (72 [75%] ischaemic infarction) in the corresponding control period. None of the comparisons were statistically significant. There was also no difference in the rate of cardioembolic infarction from atrial fibrillation between the study periods. Patients admitted during the February 2011 earthquake period were less likely to be discharged directly home when compared to the control period (31.2% versus 46.9%, p=0.036). There was no observable trend in the number of weekly stroke admissions between the 2 weeks leading to and 6 weeks following the earthquakes. Our results suggest that severe psychological stress from earthquakes did not influence the subsequent short term risk of acute stroke, but the severity of the earthquake in February 2011 and associated civil structural damages may have influenced the pattern of discharge for stroke patients. Copyright © 2013 Elsevier Ltd. All rights reserved.

  5. Earthquake risk assessment of Alexandria, Egypt

    Science.gov (United States)

    Badawy, Ahmed; Gaber, Hanan; Ibrahim, Hamza

    2015-01-01

    Throughout historical and recent times, Alexandria has suffered great damage due to earthquakes from both near- and far-field sources. Sometimes, the sources of such damages are not well known. During the twentieth century, the city was shaken by several earthquakes generated from inland dislocations (e.g., 29 Apr. 1974, 12 Oct. 1992, and 28 Dec. 1999) and the African continental margin (e.g., 12 Sept. 1955 and 28 May 1998). Therefore, this study estimates the earthquake ground shaking and the consequent impacts in Alexandria on the basis of two earthquake scenarios. The simulation results show that Alexandria affected by both earthquakes scenarios relatively in the same manner despite the number of casualties during the first scenario (inland dislocation) is twice larger than the second one (African continental margin). An expected percentage of 2.27 from Alexandria's total constructions (12.9 millions, 2006 Census) will be affected, 0.19 % injuries and 0.01 % deaths of the total population (4.1 millions, 2006 Census) estimated by running the first scenario. The earthquake risk profile reveals that three districts (Al-Montazah, Al-Amriya, and Shark) lie in high seismic risks, two districts (Gharb and Wasat) are in moderate, and two districts (Al-Gomrok and Burg El-Arab) are in low seismic risk level. Moreover, the building damage estimations reflect that Al-Montazah is the highest vulnerable district whereas 73 % of expected damages were reported there. The undertaken analysis shows that the Alexandria urban area faces high risk. Informal areas and deteriorating buildings and infrastructure make the city particularly vulnerable to earthquake risks. For instance, more than 90 % of the estimated earthquake risks (buildings damages) are concentrated at the most densely populated (Al-Montazah, Al-Amriya, and Shark) districts. Moreover, about 75 % of casualties are in the same districts.

  6. Viral infections stimulate the metabolism and shape prokaryotic assemblages in submarine mud volcanoes.

    Science.gov (United States)

    Corinaldesi, Cinzia; Dell'Anno, Antonio; Danovaro, Roberto

    2012-06-01

    Mud volcanoes are geological structures in the oceans that have key roles in the functioning of the global ecosystem. Information on the dynamics of benthic viruses and their interactions with prokaryotes in mud volcano ecosystems is still completely lacking. We investigated the impact of viral infection on the mortality and assemblage structure of benthic prokaryotes of five mud volcanoes in the Mediterranean Sea. Mud volcano sediments promote high rates of viral production (1.65-7.89 × 10(9) viruses g(-1) d(-1)), viral-induced prokaryotic mortality (VIPM) (33% cells killed per day) and heterotrophic prokaryotic production (3.0-8.3 μgC g(-1) d(-1)) when compared with sediments outside the mud volcano area. The viral shunt (that is, the microbial biomass converted into dissolved organic matter as a result of viral infection, and thus diverted away from higher trophic levels) provides 49 mgC m(-2) d(-1), thus fuelling the metabolism of uninfected prokaryotes and contributing to the total C budget. Bacteria are the dominant components of prokaryotic assemblages in surface sediments of mud volcanoes, whereas archaea dominate the subsurface sediment layers. Multivariate multiple regression analyses show that prokaryotic assemblage composition is not only dependant on the geochemical features and processes of mud volcano ecosystems but also on synergistic interactions between bottom-up (that is, trophic resources) and top-down (that is, VIPM) controlling factors. Overall, these findings highlight the significant role of the viral shunt in sustaining the metabolism of prokaryotes and shaping their assemblage structure in mud volcano sediments, and they provide new clues for our understanding of the functioning of cold-seep ecosystems.

  7. Precursory diffuse carbon dioxide degassing signature related to a 5.1 magnitude earthquake in El Salvador, Central America

    Science.gov (United States)

    Salazar, J. M. L.; Pérez, N. M.; Hernández, P. A.; Soriano, T.; Barahona, F.; Olmos, R.; Cartagena, R.; López, D. L.; Lima, R. N.; Melián, G.; Galindo, I.; Padrón, E.; Sumino, H.; Notsu, K.

    2002-12-01

    Anomalous changes in the diffuse emission of carbon dioxide have been observed before some of the aftershocks of the 13 February 2001 El Salvador earthquake (magnitude 6.6). A significant increase in soil CO 2 efflux was detected 8 days before a 5.1 magnitude earthquake on 8 May 2001 25 km away from the observation site. In addition, pre- and co-seismic CO 2 efflux variations have also been observed related to the onset of a seismic swarm beneath San Vicente volcano on May 2001. Strain changes and/or fluid pressure fluctuations prior to earthquakes in the crust are hypothesized to be responsible for the observed variations in gas efflux at the surface environment of San Vicente volcano.

  8. Earthquakes and Schools

    Science.gov (United States)

    National Clearinghouse for Educational Facilities, 2008

    2008-01-01

    Earthquakes are low-probability, high-consequence events. Though they may occur only once in the life of a school, they can have devastating, irreversible consequences. Moderate earthquakes can cause serious damage to building contents and non-structural building systems, serious injury to students and staff, and disruption of building operations.…

  9. Bam Earthquake in Iran

    CERN Multimedia

    2004-01-01

    Following their request for help from members of international organisations, the permanent Mission of the Islamic Republic of Iran has given the following bank account number, where you can donate money to help the victims of the Bam earthquake. Re: Bam earthquake 235 - UBS 311264.35L Bubenberg Platz 3001 BERN

  10. Tradable Earthquake Certificates

    NARCIS (Netherlands)

    Woerdman, Edwin; Dulleman, Minne

    2018-01-01

    This article presents a market-based idea to compensate for earthquake damage caused by the extraction of natural gas and applies it to the case of Groningen in the Netherlands. Earthquake certificates give homeowners a right to yearly compensation for both property damage and degradation of living

  11. Tremor Source Location at Okmok Volcano

    Science.gov (United States)

    Reyes, C. G.; McNutt, S. R.

    2007-12-01

    Initial results using an amplitude-based tremor location program have located several active tremor episodes under Cone A, a vent within Okmok volcano's 10 km caldera. Okmok is an andesite volcano occupying the north-eastern half of Umnak Island, in the Aleutian islands. Okmok is defined by a ~2000 y.b.p. caldera that contains multiple cinder cones. Cone A, the youngest of these, extruded lava in 1997 covering the caldera floor. Since April 2003, continuous seismic data have been recorded from eight vertical short-period stations (L4-C's) installed at distances from Cone A ranging from 2 km to 31 km. In 2004 four additional 3- component broadband stations were added, co-located with continuous GPS stations. InSAR and GPS measurements of post-eruption deformation show that Okmok experienced several periods of rapid inflation (Mann and Freymueller, 2002), from the center of the 10 km diameter caldera. While there are few locatable VT earthquakes, there has been nearly continuous low-level tremor with stronger amplitude bursts occurring at variable rates and durations. The character of occurrence remained relatively constant over the course of days to weeks until the signal ceased in mid 2005. Within any day, tremor behavior remains fairly consistent, with bursts closely resembling each other, suggesting a single main process or source location. The tremor is composed of irregular waves with a broad range of frequencies, though most energy resides between ~2 Hz and 6 Hz. Attempts to locate the tremor using traditional arrival time methods fail because the signal is emergent, with envelopes too ragged to correlate on time scales that hold much hope for a location. Instead, focus was shifted to the amplitude ratios at various stations. Candidates for the tremor source include the center of inflation and Cone A, 3 km to the south-west. For all dates on record, data were band pass filtered between 1 and 5 Hz, then evaluated in 20.48 second windows (N=2048, sampling rate

  12. Activity of volcanoes of Costa Rica during the period 2012-2013

    International Nuclear Information System (INIS)

    Alpizar, Yemerit; Mora, Mauricio M.; Mora Amador, Raul; Gonzalez, Gino; Ramirez, Carlos J.; Taylor, Waldo

    2014-01-01

    A synthesis of results and observations of two years of surveillance is presented of the active volcanoes of Costa Rica (Volcan Rincon de la Vieja, Arenal, Poas, Barva, Irazu, Turrialba). The results have enriched the database of the National Seismologic Network, which has four decades of experience in the area and the implementation of technologies. The volcanic activity presented in 2012 is relatively normal with slight signs of seismic activity and phreatic. An increase is presented after the earthquake Samara (Mw = 7.6). The temperature rise manifested mainly in the fumaroles, some changes in crater lake, phreatic activity and volcanic seismicity. The conditions were maintained throughout the period of this study [es

  13. Historic Eastern Canadian earthquakes

    International Nuclear Information System (INIS)

    Asmis, G.J.K.; Atchinson, R.J.

    1981-01-01

    Nuclear power plants licensed in Canada have been designed to resist earthquakes: not all plants, however, have been explicitly designed to the same level of earthquake induced forces. Understanding the nature of strong ground motion near the source of the earthquake is still very tentative. This paper reviews historical and scientific accounts of the three strongest earthquakes - St. Lawrence (1925), Temiskaming (1935), Cornwall (1944) - that have occurred in Canada in 'modern' times, field studies of near-field strong ground motion records and their resultant damage or non-damage to industrial facilities, and numerical modelling of earthquake sources and resultant wave propagation to produce accelerograms consistent with the above historical record and field studies. It is concluded that for future construction of NPP's near-field strong motion must be explicitly considered in design

  14. Episodic inflation of Akutan volcano, Alaska revealed from GPS and InSAR time series

    Science.gov (United States)

    DeGrandpre, K.; Lu, Z.; Wang, T.

    2016-12-01

    Akutan volcano is one of the most active volcanoes located long the Aleutian arc. At least 27 eruptions have been noted since 1790 and an intense swarm of volcano-tectonic earthquakes occurred in 1996. Surface deformation after the 1996 earthquake sequence has been studied using GPS and Interferometric Synthetic Aperture Radar (InSAR) separately, yet models created from these datasets require different mechanisms to produce the observed surface deformation: an inflating Mogi source results in the best approximation of displacement observed from GPS data, whereas an opening dyke is the best fit to deformation measured from InSAR. A recent study using seismic data revealed complex magmatic structures beneath the caldera, suggesting that the surface deformation may reflect more complicated mechanisms that cannot be estimated using one type of data alone. Here we integrate the surface deformation measured from GPS and InSAR to better understand the magma plumbing system beneath Akutan volcano. GPS time-series at 12 stations from 2006 to 2016 were analyzed, and two transient episodes of inflation in 2008 and 2014 were detected. These GPS stations are, however, too sparse to reveal the spatial distribution of the surface deformation. In order to better define the spatial extent of this inflation four tracks of Envisat data acquired during 2003-2010 and one track of TerraSAR-X data acquired from 2010 to 2016 were processed to produce high-resolution maps of surface deformation. These deformation maps show a consistently uplifting area on the northwestern flank of the volcano. We inverted for the source parameters required to produce the inflation using GPS, InSAR, and a dataset of GPS and InSAR measurements combined, to find that a deep Mogi source below a shallow dyke fit these datasets best. From the TerraSAR-X data, we were also able to measure the subsidence inside the summit caldera due to fumarole activity to be as high as 10 mm/yr. The complex spatial and temporal

  15. Actions at Kashiwazaki Kariwa Nuclear Power Station after the Niigataken Chuetsu-oki earthquake

    International Nuclear Information System (INIS)

    Orita, Shuichi

    2009-01-01

    'The Niigataken Chuetsu-oki Earthquake in 2007' occurred on July 16, 2007, and seismic motions beyond those of the design basis earthquake were recorded at Kashiwazaki Kariwa nuclear power station located near the epicenter. After the earthquake, inspections and seismic response analyses have been being performed to grasp seismic induced impacts on structures, systems and components (SSCs). In addition, re-definition of design basis earthquake, upgrading, management against disasters have been also being conducted. (author)

  16. Turkish Compulsory Earthquake Insurance and "Istanbul Earthquake

    Science.gov (United States)

    Durukal, E.; Sesetyan, K.; Erdik, M.

    2009-04-01

    The city of Istanbul will likely experience substantial direct and indirect losses as a result of a future large (M=7+) earthquake with an annual probability of occurrence of about 2%. This paper dwells on the expected building losses in terms of probable maximum and average annualized losses and discusses the results from the perspective of the compulsory earthquake insurance scheme operational in the country. The TCIP system is essentially designed to operate in Turkey with sufficient penetration to enable the accumulation of funds in the pool. Today, with only 20% national penetration, and about approximately one-half of all policies in highly earthquake prone areas (one-third in Istanbul) the system exhibits signs of adverse selection, inadequate premium structure and insufficient funding. Our findings indicate that the national compulsory earthquake insurance pool in Turkey will face difficulties in covering incurring building losses in Istanbul in the occurrence of a large earthquake. The annualized earthquake losses in Istanbul are between 140-300 million. Even if we assume that the deductible is raised to 15%, the earthquake losses that need to be paid after a large earthquake in Istanbul will be at about 2.5 Billion, somewhat above the current capacity of the TCIP. Thus, a modification to the system for the insured in Istanbul (or Marmara region) is necessary. This may mean an increase in the premia and deductible rates, purchase of larger re-insurance covers and development of a claim processing system. Also, to avoid adverse selection, the penetration rates elsewhere in Turkey need to be increased substantially. A better model would be introduction of parametric insurance for Istanbul. By such a model the losses will not be indemnified, however will be directly calculated on the basis of indexed ground motion levels and damages. The immediate improvement of a parametric insurance model over the existing one will be the elimination of the claim processing

  17. Conditions of deep magma chamber beneath Fuji volcano estimated from high- P experiments

    Science.gov (United States)

    Asano, K.; Takahashi, E.; Hamada, M.; Ushioda, M.; Suzuki, T.

    2012-12-01

    Fuji volcano, the largest in volume and eruption rate in Japan, is located at the center of Honshu, where North America, Eurasia and Philippine Sea plates meets. Because of the significance of Fuji volcano both in tectonic settings and potential volcanic hazard (particularly after the M9 earthquake in 2011), precise knowledge on its magma feeding system is essentially important. Composition of magma erupted from Fuji volcano in the last 100ky is predominantly basalt (SiO2=50-52wt%, FeO/MgO=1.5-3.0). Total lack of silica-rich magma (basaltic andesite and andesite) which are always present in other nearby volcanoes (e.g., Hakone, Izu-Oshima, see Fig.1) is an important petrologic feature of Fuji volcano. Purpose of this study is to constrain the depth of magma chamber of Fuji volcano and explain its silica-nonenrichment trend. High pressure melting experiments were carried out using two IHPVs at the Magma Factory, Tokyo Institute of Technology (SMC-5000 and SMC-8600, Tomiya et al., 2010). Basalt scoria Tr-1 which represents the final ejecta of Hoei eruption in AD1707, was adopted as a starting material. At 4kbar, temperature conditions were 1050, 1100 and 1150C, and H2O contents were 1.3, 2.7 and 4.7 wt.%, respectively. At 7kbar, temperature conditions were 1075, 1100 and 1125C, and H2O contents were 1.0, 1.1, 3.6 and 6.3wt.%, respectively. The fO2 was controlled at NNO buffer. At 4kbar, crystallization sequence at 3 wt% H2O is magnetite, plagioclase, clinopyroxene and finally orthopyroxene. At 7 kbar, and ~3 wt% H2O, the three minerals (opx, cpx, pl) appears simultaneously near the liquidus. Compositional trend of melt at 4 kbar and 7 kbar are shown with arrows in Fig.1. Because of the dominant crystallization of silica-rich opx at 7 kbar, composition of melt stays in the range SiO2=50-52wt% as predicted by Fujii (2007). Absence of silica-rich rocks in Fuji volcano may be explained by the tectonic setting of the volcano. Because Fuji volcano locates on the plate

  18. Exploring Geology on the World-Wide Web--Volcanoes and Volcanism.

    Science.gov (United States)

    Schimmrich, Steven Henry; Gore, Pamela J. W.

    1996-01-01

    Focuses on sites on the World Wide Web that offer information about volcanoes. Web sites are classified into areas of Global Volcano Information, Volcanoes in Hawaii, Volcanoes in Alaska, Volcanoes in the Cascades, European and Icelandic Volcanoes, Extraterrestrial Volcanism, Volcanic Ash and Weather, and Volcano Resource Directories. Suggestions…

  19. Relative Seismic Velocity Variations Correlate with Deformation at Kīlauea Volcano.

    Science.gov (United States)

    Donaldson, C.; Caudron, C.; Green, R. G.; White, R. S.

    2016-12-01

    Passive interferometry using ambient seismic noise is an appealing monitoring tool at volcanoes. The continuous nature of seismic noise provides better temporal resolution than earthquake interferometry and ambient noise may be sensitive to changes at depths that do not deform the volcano surface. Despite this, to our knowledge, no studies have yet comprehensively compared deformation and velocity at a volcano over a significant length of time. We use a volcanic tremor source (approximately 0.3 - 1.0 Hz) at Kīlauea volcano as a source for interferometry to measure relative velocity changes with time. The tremor source that dominates the cross correlations is located under the Halema'uma'u caldera at Kīlauea summit. By cross-correlating the vertical component of day-long seismic records between 200 pairs of stations, we extract coherent and temporally consistent coda wave signals with time lags of up to 70 seconds. Our resulting time series of relative velocity shows a remarkable correlation with the tilt record measured at Kīlauea summit. Kīlauea summit is continually inflating and deflating as the level of the lava lake rises and falls. During these deflation-inflation (DI) events the tilt increases (inflation), as the velocity increases, on the scale of days to weeks. In contrast, we also detect a longer-term velocity decrease between 2011-2015 as the volcano slowly inflates. We suggest that variations in velocity result from opening and closing cracks and pores due to changes in magma pressurization. Early modeling results indicate that pressurizing magma reservoirs at different depths can result in opposite changes in compression/extension at the surface. The consistent correlation of relative velocity and deformation in this study provides an opportunity to better understand the mechanism causing velocity changes, which currently limits the scope of passive interferometry as a monitoring tool.

  20. Geophysical Exploration on the Structure of Volcanoes: Two Case Histories

    Energy Technology Data Exchange (ETDEWEB)

    Furumoto, A. S.

    1974-01-01

    Geophysical methods of exploration were used to determine the internal structure of Koolau Volcano in Hawaii and of Rabaul Volcano in New Guinea. By use of gravity and seismic data the central vent or plug of Koolau Volcano was outlined. Magnetic data seem to indicate that the central plug is still above the Curie Point. If so, the amount of heat energy available is tremendous. As for Rabaul Volcano, it is located in a region characterized by numerous block faulting. The volcano is only a part of a large block that has subsided. Possible geothermal areas exist near the volcano but better potential areas may exist away from the volcano.

  1. Instrumentation Recommendations for Volcano Monitoring at U.S. Volcanoes Under the National Volcano Early Warning System

    Science.gov (United States)

    Moran, Seth C.; Freymueller, Jeff T.; LaHusen, Richard G.; McGee, Kenneth A.; Poland, Michael P.; Power, John A.; Schmidt, David A.; Schneider, David J.; Stephens, George; Werner, Cynthia A.; White, Randall A.

    2008-01-01

    As magma moves toward the surface, it interacts with anything in its path: hydrothermal systems, cooling magma bodies from previous eruptions, and (or) the surrounding 'country rock'. Magma also undergoes significant changes in its physical properties as pressure and temperature conditions change along its path. These interactions and changes lead to a range of geophysical and geochemical phenomena. The goal of volcano monitoring is to detect and correctly interpret such phenomena in order to provide early and accurate warnings of impending eruptions. Given the well-documented hazards posed by volcanoes to both ground-based populations (for example, Blong, 1984; Scott, 1989) and aviation (for example, Neal and others, 1997; Miller and Casadevall, 2000), volcano monitoring is critical for public safety and hazard mitigation. Only with adequate monitoring systems in place can volcano observatories provide accurate and timely forecasts and alerts of possible eruptive activity. At most U.S. volcanoes, observatories traditionally have employed a two-component approach to volcano monitoring: (1) install instrumentation sufficient to detect unrest at volcanic systems likely to erupt in the not-too-distant future; and (2) once unrest is detected, install any instrumentation needed for eruption prediction and monitoring. This reactive approach is problematic, however, for two reasons. 1. At many volcanoes, rapid installation of new ground-1. based instruments is difficult or impossible. Factors that complicate rapid response include (a) eruptions that are preceded by short (hours to days) precursory sequences of geophysical and (or) geochemical activity, as occurred at Mount Redoubt (Alaska) in 1989 (24 hours), Anatahan (Mariana Islands) in 2003 (6 hours), and Mount St. Helens (Washington) in 1980 and 2004 (7 and 8 days, respectively); (b) inclement weather conditions, which may prohibit installation of new equipment for days, weeks, or even months, particularly at

  2. The Perception of Volcanic Risk in Kona Communities from Mauna Loa and Hualalai Volcanoes, Hawai`i

    Science.gov (United States)

    Gregg, C. E.; Houghton, B. F.; Johnston, D. M.; Paton, D.; Swanson, D. A.

    2002-12-01

    Hawai`i's coastal communities are becoming increasingly vulnerable to natural hazards as a consequence of increasing population and infrastructure. Volcanic hazards in Kona (i.e., western side of the island) stem primarily from Mauna Loa and Hualalai volcanoes. The former has erupted thirty-nine times since 1832. Lava flows were emplaced in Kona during six of these, but last impacted Kona in 1950. Hualalai last erupted in c. 1800. The most recent eruptions at each volcano were damaging to society, but future eruptions would exact much greater impacts. The second largest city on the island, several resort complexes, and an international airport are located within 15 km of vents. Society's proximity to potential eruptive sources, a potential for relatively fast moving lavas, and the relatively long time intervals since the last eruptions in Kona, are the stimuli for this study of risk perception. Target populations were high school students and their parents, and the greater adult public (n=462). Using this data, we discuss threat knowledge as an influence on risk perception and perceptions as a driving mechanism for preparedness. Threat knowledge and perception of risk were found to be low to moderate. On average less than two-thirds of residents were aware of the most recent eruptions that impacted Kona and a minority felt that Mauna Loa and Hualalai could erupt again. Furthermore, only about one-third were aware that lava flows could reach the coast in Kona in under three hours. Lava flows and ash fall were perceived to be among the least likely hazards to affect the respondent's community. Not unexpectedly, individual preparedness measures were found to be limited to simple tasks, while measures specific to infrequent hazard events such as volcanic eruptions and earthquakes were seldom adopted. Respondents exhibit an "unrealistic optimism bias" and infer that responsibility for community preparedness for future eruptions rests primarily with officials. Hazard

  3. Volcanic tremor and local earthquakes at Copahue volcanic complex, Southern Andes, Argentina

    Science.gov (United States)

    Ibáñez, J. M.; Del Pezzo, E.; Bengoa, C.; Caselli, A.; Badi, G.; Almendros, J.

    2008-07-01

    In the present paper we describe the results of a seismic field survey carried out at Copahue Volcano, Southern Andes, Argentina, using a small-aperture, dense seismic antenna. Copahue Volcano is an active volcano that exhibited a few phreatic eruptions in the last 20 years. The aim of this experiment was to record and classify the background seismic activity of this volcanic area, and locate the sources of local earthquakes and volcanic tremor. Data consist of several volcano-tectonic (VT) earthquakes, and many samples of back-ground seismic noise. We use both ordinary spectral, and multi-spectral techniques to measure the spectral content, and an array technique [Zero Lag Cross Correlation technique] to measure the back-azimuth and apparent slowness of the signals propagating across the array. We locate VT earthquakes using a procedure based on the estimate of slowness vector components and S-P time. VT events are located mainly along the border of the Caviahue caldera lake, positioned at the South-East of Copahue volcano, in a depth interval of 1-3 km below the surface. The background noise shows the presence of many transients with high correlation among the array stations in the frequency band centered at 2.5 Hz. These transients are superimposed to an uncorrelated background seismic signal. Array solutions for these transients show a predominant slowness vector pointing to the exploited geothermal field of "Las Maquinitas" and "Copahue Village", located about 6 km north of the array site. We interpret this coherent signal as a tremor generated by the activity of the geothermal field.

  4. Volcanic Eruption Forecasts From Accelerating Rates of Drumbeat Long-Period Earthquakes

    Science.gov (United States)

    Bell, Andrew F.; Naylor, Mark; Hernandez, Stephen; Main, Ian G.; Gaunt, H. Elizabeth; Mothes, Patricia; Ruiz, Mario

    2018-02-01

    Accelerating rates of quasiperiodic "drumbeat" long-period earthquakes (LPs) are commonly reported before eruptions at andesite and dacite volcanoes, and promise insights into the nature of fundamental preeruptive processes and improved eruption forecasts. Here we apply a new Bayesian Markov chain Monte Carlo gamma point process methodology to investigate an exceptionally well-developed sequence of drumbeat LPs preceding a recent large vulcanian explosion at Tungurahua volcano, Ecuador. For more than 24 hr, LP rates increased according to the inverse power law trend predicted by material failure theory, and with a retrospectively forecast failure time that agrees with the eruption onset within error. LPs resulted from repeated activation of a single characteristic source driven by accelerating loading, rather than a distributed failure process, showing that similar precursory trends can emerge from quite different underlying physics. Nevertheless, such sequences have clear potential for improving forecasts of eruptions at Tungurahua and analogous volcanoes.

  5. Harnessing the Collective Power of Eyewitnesses for Improved Earthquake Information

    Science.gov (United States)

    Bossu, R.; Lefebvre, S.; Mazet-Roux, G.; Steed, R.

    2013-12-01

    The Euro-Med Seismological Centre (EMSC) operates the second global earthquake information website (www.emsc-csem.org) which attracts 2 million visits a month from about 200 different countries. We collect information about earthquakes' effects from eyewitnesses such as online questionnaires, geolocated pics to rapidly constrain impact scenario. At the beginning, the collection was purely intended to address a scientific issue: the rapid evaluation of earthquake's impact. However, it rapidly appears that the understanding of eyewitnesses' expectations and motivations in the immediate aftermath of an earthquake was essential to optimise this data collection. Crowdsourcing information on earthquake's effects does not apply to a pre-existing community. By definition, eyewitnesses only exist once the earthquake has struck. We developed a strategy on social networks (Facebook, Google+, Twitter...) to interface with spontaneously emerging online communities of eyewitnesses. The basic idea is to create a positive feedback loop: attract eyewitnesses and engage with them by providing expected earthquake information and services, collect their observations, collate them for improved earthquake information services to attract more witnesses. We will present recent examples to illustrate how important the use of social networks is to engage with eyewitnesses especially in regions of low seismic activity where people are unaware of existing Internet resources dealing with earthquakes. A second type of information collated in our information services is derived from the real time analysis of the traffic on our website in the first minutes following an earthquake occurrence, an approach named flashsourcing. We show, using the example of the Mineral, Virginia earthquake that the arrival times of eyewitnesses of our website follows the propagation of the generated seismic waves and then, that eyewitnesses can be considered as ground motion sensors. Flashsourcing discriminates felt

  6. Earthquakes, November-December 1977

    Science.gov (United States)

    Person, W.J.

    1978-01-01

    Two major earthquakes occurred in the last 2 months of the year. A magnitude 7.0 earthquake struck San Juan Province, Argentina, on November 23, causing fatalities and damage. The second major earthquake was a magnitude 7.0 in the Bonin Islands region, an unpopulated area. On December 19, Iran experienced a destructive earthquake, which killed over 500.

  7. Earthquakes, September-October 1986

    Science.gov (United States)

    Person, W.J.

    1987-01-01

    There was one great earthquake (8.0 and above) during this reporting period in the South Pacific in the Kermadec Islands. There were no major earthquakes (7.0-7.9) but earthquake-related deaths were reported in Greece and in El Salvador. There were no destrcutive earthquakes in the United States.

  8. Looking inside volcanoes with the Imaging Atmospheric Cherenkov Telescopes

    Science.gov (United States)

    Del Santo, M.; Catalano, O.; Cusumano, G.; La Parola, V.; La Rosa, G.; Maccarone, M. C.; Mineo, T.; Sottile, G.; Carbone, D.; Zuccarello, L.; Pareschi, G.; Vercellone, S.

    2017-12-01

    Cherenkov light is emitted when charged particles travel through a dielectric medium with velocity higher than the speed of light in the medium. The ground-based Imaging Atmospheric Cherenkov Telescopes (IACT), dedicated to the very-high energy γ-ray Astrophysics, are based on the detection of the Cherenkov light produced by relativistic charged particles in a shower induced by TeV photons interacting with the Earth atmosphere. Usually, an IACT consists of a large segmented mirror which reflects the Cherenkov light onto an array of sensors, placed at the focal plane, equipped by fast electronics. Cherenkov light from muons is imaged by an IACT as a ring, when muon hits the mirror, or as an arc when the impact point is outside the mirror. The Cherenkov ring pattern contains information necessary to assess both direction and energy of the incident muon. Taking advantage of the muon detection capability of IACTs, we present a new application of the Cherenkov technique that can be used to perform the muon radiography of volcanoes. The quantitative understanding of the inner structure of a volcano is a key-point to monitor the stages of the volcano activity, to forecast the next eruptive style and, eventually, to mitigate volcanic hazards. Muon radiography shares the same principle as X-ray radiography: muons are attenuated by higher density regions inside the target so that, by measuring the differential attenuation of the muon flux along different directions, it is possible to determine the density distribution of the interior of a volcano. To date, muon imaging of volcanic structures has been mainly achieved with detectors made up of scintillator planes. The advantage of using Cherenkov telescopes is that they are negligibly affected by background noise and allow a consistently improved spatial resolution when compared to the majority of the current detectors.

  9. Developing geophysical monitoring at Mayon volcano, a collaborative project EOS-PHIVOLCS

    Science.gov (United States)

    Hidayat, D.; Laguerta, E.; Baloloy, A.; Valerio, R.; Marcial, S. S.

    2011-12-01

    Mayon is an openly-degassed volcano, producing mostly small, frequent eruptions, most recently in Aug-Sept 2006 and Dec 2009. Mayon volcano status is level 1 with low seismicity dominated mostly local and regional tectonic earthquakes with continuous emission of SO2 from its crater. A research collaboration between Earth Observatory of Singapore-NTU and Philippine Institute of Volcanology and Seismology (PHIVOLCS) have been initiated in 2010 with effort to develop a multi-disciplinary monitoring system around Mayon includes geophysical monitoring, gas geochemical monitoring, and petrologic studies. Currently there are 4 broadband seismographs, 3 short period instruments, and 4 tiltmeters. These instruments will be telemetered to the Lignon Hill Volcano Observatory through radio and 3G broadband internet. We also make use of our self-made low-cost datalogger which has been operating since Jan 2011, performing continuous data acquisition with sampling rate of 20 minute/sample and transmitted through gsm network. First target of this monitoring system is to obtain continuous multi parameter data transmitted in real time to the observatory from different instruments. Tectonically, Mayon is located in the Oas Graben, a northwest-trending structural depression. Previous study using InSAR data, showing evidence of a left-lateral oblique slip movement of the fault North of Mayon. Understanding on what structures active deformation is occurring and how deformation signal is currently partitioned between tectonic and volcanic origin is a key for characterizing magma movement in the time of unrest. Preliminary analysis of the tangential components of tiltmeters (particularly the stations 5 and 7.5 NE from the volcano) shows gradual inflation movement over a few months period. The tangential components for tiltmeters are roughly perpendicular to the fault north of Mayon. This may suggest downward tilting of the graben in the northern side of Mayon. Another possibility is that

  10. Unzipping of the volcano arc, Japan

    Science.gov (United States)

    Stern, R.J.; Smoot, N.C.; Rubin, M.

    1984-01-01

    A working hypothesis for the recent evolution of the southern Volcano Arc, Japan, is presented which calls upon a northward-progressing sundering of the arc in response to a northward-propagating back-arc basin extensional regime. This model appears to explain several localized and recent changes in the tectonic and magrnatic evolution of the Volcano Arc. Most important among these changes is the unusual composition of Iwo Jima volcanic rocks. This contrasts with normal arc tholeiites typical of the rest of the Izu-Volcano-Mariana and other primitive arcs in having alkaline tendencies, high concentrations of light REE and other incompatible elements, and relatively high silica contents. In spite of such fractionated characteristics, these lavas appear to be very early manifestations of a new volcanic and tectonic cycle in the southern Volcano Arc. These alkaline characteristics and indications of strong regional uplift are consistent with the recent development of an early stage of inter-arc basin rifting in the southern Volcano Arc. New bathymetric data are presented in support of this model which indicate: 1. (1) structural elements of the Mariana Trough extend north to the southern Volcano Arc. 2. (2) both the Mariana Trough and frontal arc shoal rapidly northwards as the Volcano Arc is approached. 3. (3) rugged bathymetry associated with the rifted Mariana Trough is replaced just south of Iwo Jima by the development of a huge dome (50-75 km diameter) centered around Iwo Jima. Such uplifted domes are the immediate precursors of rifts in other environments, and it appears that a similar situation may now exist in the southern Volcano Arc. The present distribution of unrifted Volcano Arc to the north and rifted Mariana Arc to the south is interpreted not as a stable tectonic configuration but as representing a tectonic "snapshot" of an arc in the process of being rifted to form a back-arc basin. ?? 1984.

  11. Predictors of psychological resilience amongst medical students following major earthquakes.

    Science.gov (United States)

    Carter, Frances; Bell, Caroline; Ali, Anthony; McKenzie, Janice; Boden, Joseph M; Wilkinson, Timothy; Bell, Caroline

    2016-05-06

    To identify predictors of self-reported psychological resilience amongst medical students following major earthquakes in Canterbury in 2010 and 2011. Two hundred and fifty-three medical students from the Christchurch campus, University of Otago, were invited to participate in an electronic survey seven months following the most severe earthquake. Students completed the Connor-Davidson Resilience Scale, the Depression, Anxiety and Stress Scale, the Post-traumatic Disorder Checklist, the Work and Adjustment Scale, and the Eysenck Personality Questionnaire. Likert scales and other questions were also used to assess a range of variables including demographic and historical variables (eg, self-rated resilience prior to the earthquakes), plus the impacts of the earthquakes. The response rate was 78%. Univariate analyses identified multiple variables that were significantly associated with higher resilience. Multiple linear regression analyses produced a fitted model that was able to explain 35% of the variance in resilience scores. The best predictors of higher resilience were: retrospectively-rated personality prior to the earthquakes (higher extroversion and lower neuroticism); higher self-rated resilience prior to the earthquakes; not being exposed to the most severe earthquake; and less psychological distress following the earthquakes. Psychological resilience amongst medical students following major earthquakes was able to be predicted to a moderate extent.

  12. Topographic changes and their driving factors after 2008 Wenchuan Earthquake

    Science.gov (United States)

    Li, C.; Wang, M.; Xie, J.; Liu, K.

    2017-12-01

    The Wenchuan Ms 8.0 Earthquake caused topographic change in the stricken areas because of the formation of numerous coseismic landslides. The emergence of new landslides and debris flows and movement of loose materials under the driving force of heavy rainfall could further shape the local topography. Dynamic topographic changes in mountainous areas stricken by major earthquakes have a strong linkage to the development and occurrence of secondary disasters. However, little attention has been paid to continuously monitoring mountain environment change after such earthquakes. A digital elevation model (DEM) is the main feature of the terrain surface, in our research, we extracted DEM in 2013 and 2015 of a typical mountainous area severely impacted by the 2008 Wenchuan earthquake from the ZY-3 stereo pair images with validation by field measurement. Combined with the elevation dataset in 2002 and 2010, we quantitatively assessed elevation changes in different years and qualitatively analyzed spatiotemporal variation of the terrain and mass movement across the study area. The results show that the earthquake stricken area experienced substantial elevation changes caused by seismic forces and subsequent rainfalls. Meanwhile, deposits after the earthquake are mainly accumulated on the river-channels and mountain ridges and deep gullies which increase the risk of other geo-hazards. And the heavy rainfalls after the earthquake have become the biggest driver of elevation reduction, which overwhelmed elevation increase during the major earthquake. Our study provided a better understanding of subsequent hazards and risks faced by residents and communities stricken by major earthquakes.

  13. The rise and fall of periodic 'drumbeat' seismicity at Tungurahua volcano, Ecuador

    Science.gov (United States)

    Bell, Andrew F.; Hernandez, Stephen; Gaunt, H. Elizabeth; Mothes, Patricia; Ruiz, Mario; Sierra, Daniel; Aguaiza, Santiago

    2017-10-01

    Highly periodic 'drumbeat' long period (LP) earthquakes have been described from several andesitic and dacitic volcanoes, commonly accompanying incremental ascent and effusion of viscous magma. However, the processes controlling the occurrence and characteristics of drumbeat, and LP earthquakes more generally, remain contested. Here we use new quantitative tools to describe the emergence, evolution, and degradation of drumbeat LP seismicity at the andesitic Tungurahua volcano, Ecuador, in April 2015. The signals were recorded during an episode of minor explosive activity and ash emission, without lava effusion, and are the first to be reported at Tungurahua during the ongoing 17 yrs of eruption. Following four days of high levels of continuous and 'pulsed' tremor, highly-periodic LP earthquakes first appear on 10 April. Over the next four days, inter-event times and event amplitudes evolve through a series of step-wise transitions between stable behaviors, each involving a decrease in the degree of periodicity. Families of similar waveforms persist before, during, and after drumbeat activity, but the activity levels of different families change coincidentally with transitions in event rate, amplitude, and periodicity. A complex micro-seismicity 'initiation' sequence shows pulse-like and stepwise changes in inter-event times and amplitudes in the hours preceding the onset of drumbeat activity that indicate a partial de-coupling between event size and rate. The observations increase the phenomenology of drumbeat LP earthquakes, and suggest that at Tungurahua they result from gas flux and rapid depressurization controlled by shear failure of the margins of the ascending magma column.

  14. Volcanoes

    Science.gov (United States)

    ... Extreme Heat Older Adults (Aged 65+) Infants and Children Chronic Medical Conditions Low Income Athletes Outdoor Workers Pets Hot Weather Tips Warning Signs and Symptoms FAQs Social Media How to Stay Cool Missouri Cooling Centers Extreme ...

  15. Sun, Moon and Earthquakes

    Science.gov (United States)

    Kolvankar, V. G.

    2013-12-01

    During a study conducted to find the effect of Earth tides on the occurrence of earthquakes, for small areas [typically 1000km X1000km] of high-seismicity regions, it was noticed that the Sun's position in terms of universal time [GMT] shows links to the sum of EMD [longitude of earthquake location - longitude of Moon's foot print on earth] and SEM [Sun-Earth-Moon angle]. This paper provides the details of this relationship after studying earthquake data for over forty high-seismicity regions of the world. It was found that over 98% of the earthquakes for these different regions, examined for the period 1973-2008, show a direct relationship between the Sun's position [GMT] and [EMD+SEM]. As the time changes from 00-24 hours, the factor [EMD+SEM] changes through 360 degree, and plotting these two variables for earthquakes from different small regions reveals a simple 45 degree straight-line relationship between them. This relationship was tested for all earthquakes and earthquake sequences for magnitude 2.0 and above. This study conclusively proves how Sun and the Moon govern all earthquakes. Fig. 12 [A+B]. The left-hand figure provides a 24-hour plot for forty consecutive days including the main event (00:58:23 on 26.12.2004, Lat.+3.30, Long+95.980, Mb 9.0, EQ count 376). The right-hand figure provides an earthquake plot for (EMD+SEM) vs GMT timings for the same data. All the 376 events including the main event faithfully follow the straight-line curve.

  16. Common processes at unique volcanoes – a volcanological conundrum

    OpenAIRE

    Katharine eCashman; Juliet eBiggs

    2014-01-01

    An emerging challenge in modern volcanology is the apparent contradiction between the perception that every volcano is unique, and classification systems based on commonalities among volcano morphology and eruptive style. On the one hand, detailed studies of individual volcanoes show that a single volcano often exhibits similar patterns of behavior over multiple eruptive episodes; this observation has led to the idea that each volcano has its own distinctive pattern of behavior (or “personali...

  17. Structural preconditions of West Bohemia earthquake swarms

    Czech Academy of Sciences Publication Activity Database

    Novotný, Miroslav; Špičák, Aleš; Weinlich, F. H.

    2013-01-01

    Roč. 34, č. 4 (2013), s. 491-519 ISSN 0169-3298 R&D Projects: GA MŠk LM2010008 Institutional support: RVO:67985530 Keywords : West Bohemia earthquake swarm s * depth-recursive refraction tomography * CEL09 refraction profile Subject RIV: DC - Siesmology, Volcanology, Earth Structure Impact factor: 5.112, year: 2013

  18. Linking space observations to volcano observatories in Latin America: Results from the CEOS DRM Volcano Pilot

    Science.gov (United States)

    Delgado, F.; Pritchard, M. E.; Biggs, J.; Arnold, D. W. D.; Poland, M. P.; Ebmeier, S. K.; Wauthier, C.; Wnuk, K.; Parker, A. L.; Amelug, F.; Sansosti, E.; Mothes, P. A.; Macedo, O.; Lara, L.; Zoffoli, S.; Aguilar, V.

    2015-12-01

    Within Latin American, about 315 volcanoes that have been active in the Holocene, but according to the United Nations Global Assessment of Risk 2015 report (GAR15) 202 of these volcanoes have no seismic, deformation or gas monitoring. Following the 2012 Santorini Report on satellite Earth Observation and Geohazards, the Committee on Earth Observation Satellites (CEOS) has developed a 3-year pilot project to demonstrate how satellite observations can be used to monitor large numbers of volcanoes cost-effectively, particularly in areas with scarce instrumentation and/or difficult access. The pilot aims to improve disaster risk management (DRM) by working directly with the volcano observatories that are governmentally responsible for volcano monitoring, and the project is possible thanks to data provided at no cost by international space agencies (ESA, CSA, ASI, DLR, JAXA, NASA, CNES). Here we highlight several examples of how satellite observations have been used by volcano observatories during the last 18 months to monitor volcanoes and respond to crises -- for example the 2013-2014 unrest episode at Cerro Negro/Chiles (Ecuador-Colombia border); the 2015 eruptions of Villarrica and Calbuco volcanoes, Chile; the 2013-present unrest and eruptions at Sabancaya and Ubinas volcanoes, Peru; the 2015 unrest at Guallatiri volcano, Chile; and the 2012-present rapid uplift at Cordon Caulle, Chile. Our primary tool is measurements of ground deformation made by Interferometric Synthetic Aperture Radar (InSAR) but thermal and outgassing data have been used in a few cases. InSAR data have helped to determine the alert level at these volcanoes, served as an independent check on ground sensors, guided the deployment of ground instruments, and aided situational awareness. We will describe several lessons learned about the type of data products and information that are most needed by the volcano observatories in different countries.

  19. Update of the volcanic risk map of Colima volcano, Mexico

    Science.gov (United States)

    Suarez-Plascencia, C.; Nuñez Cornu, F. J.; Marquez-Azua, B.

    2010-12-01

    The Colima volcano, located in western Mexico (19° 30.696 N, 103° 37.026 W) began its current eruptive process in February 10, 1999. This event was the basis for the development of two volcanic hazard maps: one for ballistics (rock fall) lahars, and another one for ash fall. During the period of 2003 to 2008 this volcano has had an intense effusive-explosive activity, similar to the one that took place during the period of 1890 through 1900. Intense pre-Plinian eruption in January 20, 1913, generated little economic losses in the lower parts of the volcano thanks to the low population density and low socio-economic activities at the time The current volcanic activity has triggered ballistic projections, pyroclastic and ash flows, and lahars, all have exceeded the maps limits established in 1999. Vulnerable elements within these areas have gradually changed due to the expansion of the agricultural frontier on the east and southeast sides of the Colima volcano. On the slopes of the northwest side, new blue agave Tequilana weber and avocado orchard crops have emerged along with important production of greenhouse tomato, alfalfa and fruit (citrus) crops that will eventually be processed and dried for exportation to the United States and Europe. Also, in addition to the above, large expanses of corn and sugar cane have been planted on the slopes of the volcano since the nineteenth century. The increased agricultural activity has had a direct impact in the reduction of the available forest land area. Coinciding with this increased activity, the 0.8% growth population during the period of 2000 - 2005, - due to the construction of the Guadalajara-Colima highway-, also increased this impact. The growth in vulnerability changed the level of risk with respect to the one identified in the year 1999 (Suarez, 2000), thus motivating us to perform an update to the risk map at 1:25,000 using vector models of the INEGI, SPOT images of different dates, and fieldwork done in order

  20. Hydrothermal systems and volcano geochemistry

    Science.gov (United States)

    Fournier, R.O.

    2007-01-01

    The upward intrusion of magma from deeper to shallower levels beneath volcanoes obviously plays an important role in their surface deformation. This chapter will examine less obvious roles that hydrothermal processes might play in volcanic deformation. Emphasis will be placed on the effect that the transition from brittle to plastic behavior of rocks is likely to have on magma degassing and hydrothermal processes, and on the likely chemical variations in brine and gas compositions that occur as a result of movement of aqueous-rich fluids from plastic into brittle rock at different depths. To a great extent, the model of hydrothermal processes in sub-volcanic systems that is presented here is inferential, based in part on information obtained from deep drilling for geothermal resources, and in part on the study of ore deposits that are thought to have formed in volcanic and shallow plutonic environments.

  1. The Mediterranean Supersite Volcanoes (MED-SUV) Project: an overview

    Science.gov (United States)

    Puglisi, Giuseppe

    2014-05-01

    The EC FP7 MEDiterranean SUpersite Volcanoes (MED-SUV) EC-FP7 Project, which started on June 2013, aims to improve the capacity of the scientific institutions, end users and SME forming the project consortium to assess the volcanic hazards at Italian Supersites, i.e. Mt. Etna and Campi Flegrei/Vesuvius. The Project activities will focus on the optimisation and integration of ground and space monitoring systems, the breakthrough in understanding of volcanic processes, and on the increase of the effectiveness of the coordination between the scientific and end-user communities in the hazard management. The overall goal of the project is to apply the rationale of the Supersites GEO initiative to Mt. Etna and Campi Flegrei/Vesuvius, considered as cluster of Supersites. For the purpose MED-SUV will integrate long-term observations of ground-based multidisciplinary data available for these volcanoes, i.e. geophysical, geochemical, and volcanological datasets, with Earth Observation (EO) data. Merging of different parameters over a long period will provide better understanding of the volcanic processes. In particular, given the variety of styles and intensities of the volcanic activity observed at these volcanoes, and which make them sort of archetypes for 'closed conduit ' and 'open conduit' volcanic systems, the combination of different data will allow discrimination between peculiar volcano behaviours associated with pre-, syn- and post-eruptive phases. Indeed, recognition of specific volcano patterns will allow broadening of the spectrum of knowledge of geo-hazards, as well as better parameterisation and modelling of the eruptive phenomena and of the processes occurring in the volcano supply system; thus improving the capability of carrying out volcano surveillance activities. Important impacts on the European industrial sector, arising from a partnership integrating the scientific community and SMEs to implement together new observation/monitoring sensors/systems, are

  2. Fault roughness and strength heterogeneity control earthquake size and stress drop

    KAUST Repository

    Zielke, Olaf

    2017-01-13

    An earthquake\\'s stress drop is related to the frictional breakdown during sliding and constitutes a fundamental quantity of the rupture process. High-speed laboratory friction experiments that emulate the rupture process imply stress drop values that greatly exceed those commonly reported for natural earthquakes. We hypothesize that this stress drop discrepancy is due to fault-surface roughness and strength heterogeneity: an earthquake\\'s moment release and its recurrence probability depend not only on stress drop and rupture dimension but also on the geometric roughness of the ruptured fault and the location of failing strength asperities along it. Using large-scale numerical simulations for earthquake ruptures under varying roughness and strength conditions, we verify our hypothesis, showing that smoother faults may generate larger earthquakes than rougher faults under identical tectonic loading conditions. We further discuss the potential impact of fault roughness on earthquake recurrence probability. This finding provides important information, also for seismic hazard analysis.

  3. Support motions for mechanical components during earthquakes

    International Nuclear Information System (INIS)

    Hadjian, A.H.

    1979-01-01

    The functioning of mechanical and other equipment during and after earthquakes may not only be necessary to avoid catastrophic consequences, such as in nuclear facilities, but also to guarantee the adequate functioning of emergency facilities (hospitals and fire stations, for example) that are necessary to cope with the aftermath of an earthquake. The state-of-the-art methods used for prescribing support motions to equipment in structures is reviewed from the elementary to the more complex. Also reviewed are the justifications for the uncoupling of the equipment from the structure for purposes of analysis, and the impacts that uncertainties in the total process may have on equipment design. (author)

  4. Earthquake Ground Motion Selection

    Science.gov (United States)

    2012-05-01

    Nonlinear analyses of soils, structures, and soil-structure systems offer the potential for more accurate characterization of geotechnical and structural response under strong earthquake shaking. The increasing use of advanced performance-based desig...

  5. 1988 Spitak Earthquake Database

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The 1988 Spitak Earthquake database is an extensive collection of geophysical and geological data, maps, charts, images and descriptive text pertaining to the...

  6. Lahar hazards at Mombacho Volcano, Nicaragua

    Science.gov (United States)

    Vallance, J.W.; Schilling, S.P.; Devoli, G.

    2001-01-01

    Mombacho volcano, at 1,350 meters, is situated on the shores of Lake Nicaragua and about 12 kilometers south of Granada, a city of about 90,000 inhabitants. Many more people live a few kilometers southeast of Granada in 'las Isletas de Granada and the nearby 'Peninsula de Aseses. These areas are formed of deposits of a large debris avalanche (a fast moving avalanche of rock and debris) from Mombacho. Several smaller towns with population, in the range of 5,000 to 12,000 inhabitants are to the northwest and the southwest of Mombacho volcano. Though the volcano has apparently not been active in historical time, or about the last 500 years, it has the potential to produce landslides and debris flows (watery flows of mud, rock, and debris -- also known as lahars when they occur on a volcano) that could inundate these nearby populated areas. -- Vallance, et.al., 2001

  7. Analysis of volcano rocks by Moessbauer spectroscopy

    International Nuclear Information System (INIS)

    Sitek, J.; Dekan, J.

    2012-01-01

    In this work we have analysed the basalt rock from Mount Ba tur volcano situated on the Island of Bali in Indonesia.We compared our results with composition of basalt rocks from some other places on the Earth. (authors)

  8. Moessbauer Spectroscopy study of Quimsachata Volcano materials

    International Nuclear Information System (INIS)

    Dominguez, A.G.B.

    1988-01-01

    It has been studied volcanic lava from Quimsachata Volcano in Pem. Moessbauer Spectroscopy, X-ray diffraction, electronic and optical microscopy allowed the identification of different mineralogical phases. (A.C.AS.) [pt

  9. Lahar hazards at Agua volcano, Guatemala

    Science.gov (United States)

    Schilling, S.P.; Vallance, J.W.; Matías, O.; Howell, M.M.

    2001-01-01

    At 3760 m, Agua volcano towers more than 3500 m above the Pacific coastal plain to the south and 2000 m above the Guatemalan highlands to the north. The volcano is within 5 to 10 kilometers (km) of Antigua, Guatemala and several other large towns situated on its northern apron. These towns have a combined population of nearly 100,000. It is within about 20 km of Escuintla (population, ca. 100,000) to the south. Though the volcano has not been active in historical time, or about the last 500 years, it has the potential to produce debris flows (watery flows of mud, rock, and debris—also known as lahars when they occur on a volcano) that could inundate these nearby populated areas.

  10. Meteorite Impact "Earthquake" Features (Rock Liquefaction, Surface Wave Deformations, Seismites) from Ground Penetrating Radar (GPR) and Geoelectric Complex Resistivity/Induced Polarization (IP) Measurements, Chiemgau (Alpine Foreland, Southeast Germany)

    Science.gov (United States)

    Ernstson, K.; Poßekel, J.

    2017-12-01

    Densely spaced GPR and complex resistivity measurements on a 30,000 square meters site in a region of enigmatic sinkhole occurrences in unconsolidated Quaternary sediments have featured unexpected and highlighting results from both a meteorite impact research and an engineering geology point of view. The GPR measurements and a complex resistivity/IP electrical imaging revealed extended subrosion depressions related with a uniformly but in various degrees of intensity deformed loamy and gravelly ground down to at least 10 m depth. Two principle observations could be made from both the GPR high-resolution measurements and the more integrating resistivity and IP soundings with both petrophysical evidences in good complement. Subrosion can be shown to be the result of prominent sandy-gravelly intrusions and extrusions typical of rock liquefaction processes well known to occur during strong earthquakes. Funnel-shaped structures with diameters up to 25 m near the surface and reaching down to the floating ground water level at 10 m depth were measured. GPR radargrams could trace prominent gravelly-material transport bottom-up within the funnels. Seen in both GPR tomography and resistivity/IP sections more or less the whole investigated area is overprinted by wavy deformations of the unconsolidated sediments with wavelengths of the order of 5 - 10 m and amplitudes up to half a meter, likewise down to 10 m depth. Substantial earthquakes are not known in this region. Hence, the observed heavy underground disorder is considered the result of the prominent earthquake shattering that must have occurred during the Holocene (Bronze Age/Celtic era) Chiemgau meteorite impact event that produced a 60 km x 30 km sized crater strewn field directly hosting the investigated site. Depending on depth and size of floating aquifers local concentrations of rock liquefaction and seismic surface waves (probably LOVE waves) to produce the wavy deformations could develop, when the big

  11. Electromagnetic Manifestation of Earthquakes

    OpenAIRE

    Uvarov Vladimir

    2017-01-01

    In a joint analysis of the results of recording the electrical component of the natural electromagnetic field of the Earth and the catalog of earthquakes in Kamchatka in 2013, unipolar pulses of constant amplitude associated with earthquakes were identified, whose activity is closely correlated with the energy of the electromagnetic field. For the explanation, a hypothesis about the cooperative character of these impulses is proposed.

  12. Electromagnetic Manifestation of Earthquakes

    Directory of Open Access Journals (Sweden)

    Uvarov Vladimir

    2017-01-01

    Full Text Available In a joint analysis of the results of recording the electrical component of the natural electromagnetic field of the Earth and the catalog of earthquakes in Kamchatka in 2013, unipolar pulses of constant amplitude associated with earthquakes were identified, whose activity is closely correlated with the energy of the electromagnetic field. For the explanation, a hypothesis about the cooperative character of these impulses is proposed.

  13. The 2003 phreatomagmatic eruptions of Anatahan volcano - Textural and petrologic features of deposits at an emergent island volcano

    Science.gov (United States)

    Pallister, J.S.; Trusdell, F.A.; Brownfield, I.K.; Siems, D.F.; Budahn, J.R.; Sutley, S.F.

    2005-01-01

    Stratigraphic and field data are used in conjunction with textural and chemical evidence (including data from scanning electron microscope, electron microprobe, X-ray fluorescence, X-ray diffraction, and instrumental neutron activation analysis) to establish that the 2003 eruption of Anatahan volcano was mainly phreatomagmatic, dominated by explosive interaction of homogeneous composition low-viscosity crystal-poor andesite magma with water. The hydromagmatic mode of eruption contributed to the significant height of initial eruptive columns and to the excavation and eruption of altered rock debris from the sub-volcanic hydrothermal system. Volatile contents of glass inclusions in equilibrium phenocrysts less abundances of these constituents in matrix glass times the estimated mass of juvenile magma indicate minimum emissions of 19 kt SO2 and 13 kt Cl. This petrologic estimate of SO2 emission is an order-of-magnitude less than an estimate from TOMS. Similarly, inferred magma volumes from the petrologic data are an order of magnitude greater than those modeled from deformation data. Both discrepancies indicate additional sources of volatiles, likely derived from a separate fluid phase in the magma. The paucity of near-source volcanic-tectonic earthquakes preceding the eruption, and the dominance of sustained long-period tremor are attributed to the ease of ascent of the hot low-viscosity andesite, followed by a shallow phreatomagmatic mode of eruption. Phreatomagmatic eruptions are probably more common at emergent tropical island volcanoes, where shallow fresh-water lenses occur at near-sea-level vents. These relations suggest that phreatomagmatic explosions contributed to the formation of many of the near-sea-level craters and possibly even to the small calderas at the other Mariana islands.

  14. Fear based Education or Curiosity based Education as an Example of Earthquake and Natural Disaster Education: Results of Statistical Study in Primary Schools in Istanbul-Turkey

    Science.gov (United States)

    Ozcep, T.; Ozcep, F.

    2012-04-01

    Natural disaster reduction focuses on the urgent need for prevention activities to reduce loss of life, damage to property, infrastructure and environment, and the social and economic disruption caused by natural hazards. One of the most important factors in reduction of the potential damage of earthquakes is trained manpower. To understanding the causes of earthquakes and other natural phenomena (landslides, avalanches, floods, volcanoes, etc.) is one of the pre-conditions to show a conscious behavior. The aim of the study is to analysis and to investigate, how earthquakes and other natural phenomena are perceived by the students and the possible consequences of this perception, and their effects of reducing earthquake damage. One of the crucial questions is that is our education system fear or curiosity based education system? Effects of the damages due to earthquakes have led to look like a fear subject. In fact, due to the results of the effects, the earthquakes are perceived scary phenomena. In the first stage of the project, the learning (or perception) levels of earthquakes and other natural disasters for the students of primary school are investigated with a survey. Aim of this survey study of earthquakes and other natural phenomena is that have the students fear based or curiosity based approaching to the earthquakes and other natural events. In the second stage of the project, the path obtained by the survey are evaluated with the statistical point of approach. A questionnaire associated with earthquakes and natural disasters are applied to primary school students (that total number of them is approximately 700 pupils) to measure the curiosity and/or fear levels. The questionnaire consists of 17 questions related to natural disasters. The questions are: "What is the Earthquake ?", "What is power behind earthquake?", "What is the mental response during the earthquake ?", "Did we take lesson from earthquake's results ?", "Are you afraid of earthquake

  15. Aerial inventory of surficial geological effects induced by the recent Emilia earthquake (Italy: preliminary report

    Directory of Open Access Journals (Sweden)

    Giovanni Bertolini

    2012-10-01

    Full Text Available As a consequence of the two main shocks that recently struck the central alluvial Po Plain (May 20, 2012, Ml 5.9, and May 29, 2012, Ml 5.8, a great number of surficial geologic disturbances appeared over a wide area (ca. 500 km2, which extended up to 20 km from the epicenters. The affected area includes Mirabello, San Carlo, Sant'Agostino (Province of Ferrara, San Felice, Cavezzo, Concordia (Modena, Moglia and Quistello (Mantova. Most of the surficial effects that were observed during this study were clearly induced (directly or indirectly by sand liquefaction phenomena, such as sand volcanoes, burst of water and sand from domestic wells, tension cracks, lateral spreading and associated deformation, graben-like fracturing, and sink-holes. Other effects can probably be ascribed simply to the shaking of the ground (e.g., small collapses of irrigation canal walls. Lastly, there were also some features of dubious origin, such as two 'yellow crop spots' that are cited here with reservations. All of these data were surveyed by means of a small airplane that was especially adapted for this purpose. The aim of this study was to furnish a wide-ranging image of the surface deformation over the whole area impacted by these recent earthquakes, as an instrument towards more exhaustive research, both at the scientific and technical levels (e.g., seismic microzonation. […

  16. Intermediate earthquakes in a northern part of the Kyushu-Ryukyu arc. Kyushu-Ryukyu kohokubu iki no shoshinpatsu jishin

    Energy Technology Data Exchange (ETDEWEB)

    Kakuta, T.; Miyamachi, H.; Takagi, A. (Kagoshima Univ., Kagoshima (Japan). Faculty of Science)

    1991-06-24

    Great improvement has been made in the reduction of errors in the detection accuracy of intermediate earthquake epicenters, particularly of longitude and focal depth, by the analysis of data obtained by the observation network of Kagoshima University deployed for the purpose of observing regional seismic activities in the southern part of Kyushu. The epicenters are redetermined by adding the data observed by Fukuoka Meteorological Observatory to study the source distribution mainly. A chain of earthquakes at the depths from 119km to 177km in a vertical zone from Kaimon-dake volcano to the south and a chain of events branched off from the cluster towards Sakurajima volcano are observed. It is plausible that the existence of these seismic activities in the peripheral areas immediately below volcanos is associated with the supply of volcanic energy in Kyushu. Seismicity gaps of intermediate earthquakes are also noticeable phenomena. Although the number of earthquakes is not enough for the establishment of theories for seismic activities and seismicity gaps in the northern part of the Kyushu-Ryukyu arc, regional features are found out which is considered to be related with the characteristic thermal activity in the area of plate dipping at high angle. 27 refs., 13 figs.

  17. Deposits, petrology and mechanism of the 2010-2013 eruption of Kizimen volcano in Kamchatka, Russia

    Science.gov (United States)

    Auer, A.; Belousov, A.; Belousova, M.

    2018-04-01

    Kizimen volcano in Kamchatka is well known as a source of highly heterogeneous poorly mingled magmas ranging from dacites to basaltic andesites. In 2010-2013, the volcano produced its first historical magmatic eruption with the deposition of 0.27 km3 of block and ash pyroclastic flows accompanied by slow extrusion of a 200-m-thick, highly viscous (1010-1011 Pa s) block lava flow with a volume of 0.3 km3. The total volume of erupted magma comprised approximately 0.4 km3 DRE. We provide description of the eruption chronology, as well as the lithology and petrology of eruptive products. The erupted material is represented by banded dacite and high-silica andesite. The dacitic magma was formed during a long dormancy after the previous magmatic eruption several hundred years ago with mineral compositions indicating average pre-eruptive temperatures of 810 °C, fO2 of 0.9-1.6 log units above the nickel-nickel oxide (NNO) buffer and shallow crustal storage conditions at 123 MPa. The silica-rich andesite represents a hybrid magma, which shows signs of recent thermal and compositional disequilibrium. We suggest that the hybrid magma started to form in 1963 when a swarm of deep earthquakes indicated an input of mafic magma from depth into the 6-11-km-deep silicic magma chamber. It took the following 46 years until the magma filling the chamber reached an eruptible state. Poor mingling of the two melts is attributed to its unusually high viscosity that could be associated with the pre-eruptive long-term leakage of volatiles from the chamber through a regional tectonic fault. Our investigations have shown that shallow magma chambers of dormant volcanoes demonstrating strong persistent fumarolic activity can contain highly viscous, degassed magma of evolved composition. Reactivation of such magma chambers by injection of basic magma takes a long time (several decades). Thus, eruption forecasts at such volcanoes should include a possibility of long time lag between a swarm of

  18. Characteristic of Lokon Volcano Deformation of 2009 - 2011 Based on GPS Data

    Directory of Open Access Journals (Sweden)

    Estu Kriswati

    2014-07-01

    Full Text Available DOI: 10.17014/ijog.v7i4.147Precursor of Lokon Volcano eruptions in 2011 is believed to begin since December 2007 which was marked by increasing number of volcanic earthquakes and gas emission. To support this information, deformation method is used primarily to determine deformation characteristics of Lokon volcanic activity in the period of 2009-2011. The period of analysis is adapted to the presence of GPS data. Displacement rate of Lokon GPS observation points in the period of 2009 - 2011 ranged from 1.1 to 7 cm a year. Strain patterns that occur in the areas are compression surrounding Tompaluan crater and extension in the eastern slope. Location of the pressure source for August 2009 - March 2011 measurement was at a depth of 1800 m beneath Tompaluan crater. Deformation in the Lokon Volcano is characteristized by the compression zone in the summit and crater area caused by magma activity raised into the surface from a shallow magma source which is accompanied by a high release of volcanic gases. Accumulated pressure release and deformation rate as measured in the Lokon Volcano remain low.

  19. Effects of the 2010 Haiti Earthquake on Women's Reproductive Health.

    Science.gov (United States)

    Behrman, Julia Andrea; Weitzman, Abigail

    2016-03-01

    This article explores the effects of the 2010 Haiti earthquake on women's reproductive health, using geocoded data from the 2005 and 2012 Haiti Demographic and Health Surveys. We use geographic variation in the destructiveness of the earthquake to conduct a difference-in-difference analysis. Results indicate that heightened earthquake intensity reduced use of injectables-the most widely used modern contraceptive method in Haiti-and increased current pregnancy and current unwanted pregnancy. Analysis of impact pathways suggests that severe earthquake intensity significantly increased women's unmet need for family planning and reduced their access to condoms. The earthquake also affected other factors that influence reproductive health, including women's ability to negotiate condom use in their partnerships. Our findings highlight how disruptions to health care services following a natural disaster can have negative consequences for women's reproductive health. © 2016 The Population Council, Inc.

  20. Nowcasting Earthquakes and Tsunamis

    Science.gov (United States)

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

    2017-12-01

    The term "nowcasting" refers to the estimation of the current uncertain state of a dynamical system, whereas "forecasting" is a calculation of probabilities of future state(s). Nowcasting is a term that originated in economics and finance, referring to the process of determining the uncertain state of the economy or market indicators such as GDP at the current time by indirect means. We have applied this idea to seismically active regions, where the goal is to determine the current state of a system of faults, and its current level of progress through the earthquake cycle (http://onlinelibrary.wiley.com/doi/10.1002/2016EA000185/full). Advantages of our nowcasting method over forecasting models include: 1) Nowcasting is simply data analysis and does not involve a model having parameters that must be fit to data; 2) We use only earthquake catalog data which generally has known errors and characteristics; and 3) We use area-based analysis rather than fault-based analysis, meaning that the methods work equally well on land and in subduction zones. To use the nowcast method to estimate how far the fault system has progressed through the "cycle" of large recurring earthquakes, we use the global catalog of earthquakes, using "small" earthquakes to determine the level of hazard from "large" earthquakes in the region. We select a "small" region in which the nowcast is to be made, and compute the statistics of a much larger region around the small region. The statistics of the large region are then applied to the small region. For an application, we can define a small region around major global cities, for example a "small" circle of radius 150 km and a depth of 100 km, as well as a "large" earthquake magnitude, for example M6.0. The region of influence of such earthquakes is roughly 150 km radius x 100 km depth, which is the reason these values were selected. We can then compute and rank the seismic risk of the world's major cities in terms of their relative seismic risk

  1. Impact of Geological Changes on Regional and Global Economies

    Science.gov (United States)

    Tatiana, Skufina; Peter, Skuf'in; Vera, Samarina; Taisiya, Shatalova; Baranov, Sergey

    2017-04-01

    Periods of geological changes such as super continent cycle (300-500 million years), Wilson's cycles (300-900 million years), magmatic-tectonic cycle (150-200 million years), and cycles with smaller periods (22, 100, 1000 years) lead to a basic contradiction preventing forming methodology of the study of impact of geological changes on the global and regional economies. The reason of this contradiction is the differences of theoretical and methodological aspects of the Earth science and economics such as different time scales and accuracy of geological changes. At the present the geological models cannot provide accurate estimation of time and place where geological changes (strong earthquakes, volcanos) are expected. Places of feature (not next) catastrophic events are the only thing we have known. Thus, it is impossible to use the periodicity to estimate both geological changes and their consequences. Taking into accounts these factors we suggested a collection of concepts for estimating impact of possible geological changes on regional and global economies. We illustrated our approach by example of estimating impact of Tohoku earthquake and tsunami of March 2011 on regional and global economies. Based on this example we concluded that globalization processes increase an impact of geological changes on regional and global levels. The research is supported by Russian Foundation for Basic Research (Projects No. 16-06-00056, 16-32-00019, 16-05-00263A).

  2. The Krakatau volcano 125 years after the catastrophic eruption (August 27, 1883)

    Czech Academy of Sciences Publication Activity Database

    Špičák, Aleš; Kozák, Jan; Vaněk, Jiří; Hanuš, Václav

    2008-01-01

    Roč. 52, č. 3 (2008), s. 449-454 ISSN 0039-3169 Institutional research plan: CEZ:AV0Z30120515 Keywords : Krakatau volcano * 1883 eruption * anniversary Subject RIV: DC - Siesmology, Volcanology, Earth Structure Impact factor: 0.770, year: 2008

  3. Beyond the top of the volcano? A unified approach to electrocatalytic oxygen reduction and oxygen evolution

    Czech Academy of Sciences Publication Activity Database

    Busch, M.; Halck, N. B.; Kramm, U. I.; Siehrostami, S.; Krtil, Petr; Rossmeisl, J.

    2016-01-01

    Roč. 29, NOV 2016 (2016), s. 126-135 ISSN 2211-2855 Institutional support: RVO:61388955 Keywords : hydrogen evolution * catalytic-activity * Electrocatalysis * Oxygen reduction * Oxygen evolution * Volcano * Density functional theory Subject RIV: CF - Physical ; Theoretical Chemistry Impact factor: 12.343, year: 2016

  4. Associations between economic loss, financial strain and the psychological status of Wenchuan earthquake survivors.

    Science.gov (United States)

    Huang, Yunong; Wong, Hung; Tan, Ngoh Tiong

    2015-10-01

    This study examines the effects of economic loss on the life satisfaction and mental health of Wenchuan earthquake survivors. Economic loss is measured by earthquake impacts on the income and houses of the survivors. The correlation analysis shows that earthquake impact on income is significantly correlated with life satisfaction and depression. The regression analyses indicate that earthquake impact on income is indirectly associated with life satisfaction and depression through its effect on financial strain. The research highlights the importance of coping strategies in maintaining a balance between economic status and living demands for disaster survivors. © 2015 The Author(s). Disasters © Overseas Development Institute, 2015.

  5. Prevention of strong earthquakes: Goal or utopia?

    Science.gov (United States)

    Mukhamediev, Sh. A.

    2010-11-01

    In the present paper, we consider ideas suggesting various kinds of industrial impact on the close-to-failure block of the Earth’s crust in order to break a pending strong earthquake (PSE) into a number of smaller quakes or aseismic slips. Among the published proposals on the prevention of a forthcoming strong earthquake, methods based on water injection and vibro influence merit greater attention as they are based on field observations and the results of laboratory tests. In spite of this, the cited proofs are, for various reasons, insufficient to acknowledge the proposed techniques as highly substantiated; in addition, the physical essence of these methods has still not been fully understood. First, the key concept of the methods, namely, the release of the accumulated stresses (or excessive elastic energy) in the source region of a forthcoming strong earthquake, is open to objection. If we treat an earthquake as a phenomenon of a loss in stability, then, the heterogeneities of the physicomechanical properties and stresses along the existing fault or its future trajectory, rather than the absolute values of stresses, play the most important role. In the present paper, this statement is illustrated by the classical examples of stable and unstable fractures and by the examples of the calculated stress fields, which were realized in the source regions of the tsunamigenic earthquakes of December 26, 2004 near the Sumatra Island and of September 29, 2009 near the Samoa Island. Here, just before the earthquakes, there were no excessive stresses in the source regions. Quite the opposite, the maximum shear stresses τmax were close to their minimum value, compared to τmax in the adjacent territory. In the present paper, we provide quantitative examples that falsify the theory of the prevention of PSE in its current form. It is shown that the measures for the prevention of PSE, even when successful for an already existing fault, can trigger or accelerate a catastrophic

  6. Active volcanoes observed through Art: the contribution offered by the social networks

    Science.gov (United States)

    Neri, Marco; Neri, Emilia

    2015-04-01

    Volcanoes have always fascinated people for the wild beauty of their landscapes and also for the fear that they arouse with their eruptive actions, sometimes simply spectacular, but other times terrifying and catastrophic for human activities. In the past, volcanoes were sometimes imagined as a metaphysical gateway to the otherworld; they have inspired the creation of myths and legends ever since three thousand years ago, also represented by paintings of great artistic impact. Modern technology today offers very sophisticated and readily accessed digital tools, and volcanoes continue to be frequently photographed and highly appreciated natural phenomena. Moreover, in recent years, the spread of social networks (Facebook, Twitter, YouTube, Instagram, etc.) have made the widespread dissemination of graphic contributions even easier. The result is that very active and densely inhabited volcanoes such as Etna, Vesuvius and Aeolian Islands, in Italy, have become among the most photographed subjects in the world, providing a popular science tool with formidable influence and usefulness. The beauty of these landscapes have inspired both professional artists and photographers, as well as amateurs, who compete in the social networks for the publication of the most spectacular, artistic or simply most informative images. The end result of this often frantic popular scientific activity is at least two-fold: on one hand, it provides geoscientists and science communicators a quantity of documentation that is almost impossible to acquire through the normal systems of volcano monitoring, while on the other it raises awareness and respect for the land among the civil community.

  7. GEM - The Global Earthquake Model

    Science.gov (United States)

    Smolka, A.

    2009-04-01

    Over 500,000 people died in the last decade due to earthquakes and tsunamis, mostly in the developing world, where the risk is increasing due to rapid population growth. In many seismic regions, no hazard and risk models exist, and even where models do exist, they are intelligible only by experts, or available only for commercial purposes. The Global Earthquake Model (GEM) answers the need for an openly accessible risk management tool. GEM is an internationally sanctioned public private partnership initiated by the Organisation for Economic Cooperation and Development (OECD) which will establish an authoritative standard for calculating and communicating earthquake hazard and risk, and will be designed to serve as the critical instrument to support decisions and actions that reduce earthquake losses worldwide. GEM will integrate developments on the forefront of scientific and engineering knowledge of earthquakes, at global, regional and local scale. The work is organized in three modules: hazard, risk, and socio-economic impact. The hazard module calculates probabilities of earthquake occurrence and resulting shaking at any given location. The risk module calculates fatalities, injuries, and damage based on expected shaking, building vulnerability, and the distribution of population and of exposed values and facilities. The socio-economic impact module delivers tools for making educated decisions to mitigate and manage risk. GEM will be a versatile online tool, with open source code and a map-based graphical interface. The underlying data will be open wherever possible, and its modular input and output will be adapted to multiple user groups: scientists and engineers, risk managers and decision makers in the public and private sectors, and the public-at- large. GEM will be the first global model for seismic risk assessment at a national and regional scale, and aims to achieve broad scientific participation and independence. Its development will occur in a

  8. Seismic and Gas Analyses Imply Magmatic Intrusion at Iliamna Volcano, Alaska in 2012

    Science.gov (United States)

    Prejean, S. G.; Werner, C. A.; Buurman, H.; Doukas, M. P.; Kelly, P. J.; Kern, C.; Ketner, D.; Stihler, S.; Thurber, C. H.; West, M. E.

    2012-12-01

    In early 2012, Iliamna Volcano, an ice-covered andesitic stratovolcano located in the Cook Inlet region of Alaska, had a vigorous earthquake swarm that included both brittle-failure earthquakes (Mvolume has otherwise been seismically quiet except during a possible magmatic intrusion at Iliamna in 1996, when it sustained a similar swarm (Roman et al., 2004, J. Volc. Geotherm. Res., v. 130, p. 265-284). Analysis of the relative amplitudes between the small low-frequency and located brittle failure events indicates that their sources are geographically separate, with the low-frequency events sourced closer to the fumarolically active summit region, ~4 km north of the brittle failure events. Airborne gas-emission measurements on March 17 revealed emission rates of up to 2000 and 580 tonnes per day (t/d) of CO2 and SO2, respectively, and a molar C/S ratio of 5. Visual observations from the flight revealed unusually vigorous fumarole activity near the summit. Subsequent measurements on June 20 and 22 showed continued high emissions of up to 1190 and 440 t/d of CO2 and SO2, respectively, with a C/S ratio of 4. These emission measurements are similar to those measured during the height of the 1996 unrest episode and are significantly above background measurements between 1998 and August 2011, which were typically below 100 and 60 t/d of CO2 and SO2. Taken together, gas and seismic data suggest that the earthquake swarm was driven by magmatic intrusion. Gas flux rates are consistent with those measured for degassing andesitic magmas in the shallow crust at other Cook Inlet volcanoes. Increased heat and degassing likely caused small low-frequency events in the shallow hydrothermal system near the volcano's summit, and/or may have destabilized the glacier, triggering shallow low-frequency glacial events. This unrest episode demonstrates how magmatic intrusions can cause spatially disparate earthquake swarms in hydrothermal systems and on pre-existing crustal structures.

  9. Interdisciplinary Studies of Eruption at Chaitén Volcano, Chile

    Science.gov (United States)

    Pallister, John S.; Major, Jon J.; Pierson, Thomas C.; Hoblitt, Richard P.; Lowenstern, Jacob B.; Eichelberger, John C.; Lara, Luis; Moreno, Hugo; Muñoz, Jorge; Castro, Jonathan M.; Iroumé, Andrés; Andreoli, Andrea; Jones, Julia; Swanson, Fred; Crisafulli, Charlie

    2010-10-01

    High-silica rhyolite magma fuels Earth's largest and most explosive eruptions. Recurrence intervals for such highly explosive eruptions are in the 100- to 100,000­year time range, and there have been few direct observations of such eruptions and their immediate impacts. Consequently, there was keen interest within the volcanology community when the first large eruption of high-silica rhyolite since that of Alaska's Novarupta volcano in 1912 began on 1 May 2008 at Chaitén volcano, southern Chile, a 3-kilometer­diameter caldera volcano with a prehistoric record of rhyolite eruptions [Naranjo and Stern, 2004; Servicio Nacional de Geología y Minería (SERNAGEOMIN), 2008; Carn et al., 2009; Castro and Dingwell, 2009; Lara, 2009; Muñoz et al., 2009]. Vigorous explosions occurred through 8 May 2008, after which explosive activity waned and a new lava dome was extruded.

  10. Volcanoes of México: An Interactive CD-ROM From the Smithsonian's Global Volcanism Program

    Science.gov (United States)

    Siebert, L.; Kimberly, P.; Calvin, C.; Luhr, J. F.; Kysar, G.

    2002-12-01

    xico from the Bulletin of the Global Volcanism Network and its predecessor, the Scientific Event Alert Network Bulletin, as well as early event-card notices of the Smithsonian's Center for Short-Lived Phenomena. An extensive petrologic database contains major-element analyses and other petrological and geochemical data for 1776 samples. The user also has access to a database of the Global Volcanism Program's map archives. Another option on the CD views earthquake hypocenters and volcanic eruptions from 1960 to the present plotted sequentially on a map of México and Central America. A bibliography of Mexican volcanism and geothermal research includes references cited in the Smithsonian's volcano database as well as those obtained from a search of the Georef bibliographic database. For more advanced queries and searches both the petrologic database and volcanic activity reports can be uploaded from the CD.

  11. Earthquake number forecasts testing

    Science.gov (United States)

    Kagan, Yan Y.

    2017-10-01

    We study the distributions of earthquake numbers in two global earthquake catalogues: Global Centroid-Moment Tensor and Preliminary Determinations of Epicenters. The properties of these distributions are especially required to develop the number test for our forecasts of future seismic activity rate, tested by the Collaboratory for Study of Earthquake Predictability (CSEP). A common assumption, as used in the CSEP tests, is that the numbers are described by the Poisson distribution. It is clear, however, that the Poisson assumption for the earthquake number distribution is incorrect, especially for the catalogues with a lower magnitude threshold. In contrast to the one-parameter Poisson distribution so widely used to describe earthquake occurrences, the negative-binomial distribution (NBD) has two parameters. The second parameter can be used to characterize the clustering or overdispersion of a process. We also introduce and study a more complex three-parameter beta negative-binomial distribution. We investigate the dependence of parameters for both Poisson and NBD distributions on the catalogue magnitude threshold and on temporal subdivision of catalogue duration. First, we study whether the Poisson law can be statistically rejected for various catalogue subdivisions. We find that for most cases of interest, the Poisson distribution can be shown to be rejected statistically at a high significance level in favour of the NBD. Thereafter, we investigate whether these distributions fit the observed distributions of seismicity. For this purpose, we study upper statistical moments of earthquake numbers (skewness and kurtosis) and compare them to the theoretical values for both distributions. Empirical values for the skewness and the kurtosis increase for the smaller magnitude threshold and increase with even greater intensity for small temporal subdivision of catalogues. The Poisson distribution for large rate values approaches the Gaussian law, therefore its skewness

  12. a Collaborative Cyberinfrastructure for Earthquake Seismology

    Science.gov (United States)

    Bossu, R.; Roussel, F.; Mazet-Roux, G.; Lefebvre, S.; Steed, R.

    2013-12-01

    One of the challenges in real time seismology is the prediction of earthquake's impact. It is particularly true for moderate earthquake (around magnitude 6) located close to urbanised areas, where the slightest uncertainty in event location, depth, magnitude estimates, and/or misevaluation of propagation characteristics, site effects and buildings vulnerability can dramatically change impact scenario. The Euro-Med Seismological Centre (EMSC) has developed a cyberinfrastructure to collect observations from eyewitnesses in order to provide in-situ constraints on actual damages. This cyberinfrastructure takes benefit of the natural convergence of earthquake's eyewitnesses on EMSC website (www.emsc-csem.org), the second global earthquake information website within tens of seconds of the occurrence of a felt event. It includes classical crowdsourcing tools such as online questionnaires available in 39 languages, and tools to collect geolocated pics. It also comprises information derived from the real time analysis of the traffic on EMSC website, a method named flashsourcing; In case of a felt earthquake, eyewitnesses reach EMSC website within tens of seconds to find out the cause of the shaking they have just been through. By analysing their geographical origin through their IP address, we automatically detect felt earthquakes and in some cases map the damaged areas through the loss of Internet visitors. We recently implemented a Quake Catcher Network (QCN) server in collaboration with Stanford University and the USGS, to collect ground motion records performed by volunteers and are also involved in a project to detect earthquakes from ground motions sensors from smartphones. Strategies have been developed for several social media (Facebook, Twitter...) not only to distribute earthquake information, but also to engage with the Citizens and optimise data collection. A smartphone application is currently under development. We will present an overview of this

  13. Responses to, and the short and long-term impacts of, the 1957/1958 Capelinhos volcanic eruption and associated earthquake activity on Faial, Azores

    Science.gov (United States)

    Coutinho, Rui; Chester, David K.; Wallenstein, Nicolau; Duncan, Angus M.

    2010-10-01

    The 1957/58 Capelinhos eruption on Faial Island in the Azores is well known for being an excellent example of Surtseyan hydromagmatic volcanic activity. Less well known are the responses of the Portuguese authorities to the eruption and subsequent earthquake in May 1958, and the ways in which well-thought-out and generally effective recovery programmes were put in place. At the time Portugal was ruled by a dictatorship, the Estado Novo (New State). Only superficially similar to other fascist governments in Southern Europe, the Estado Novo collected huge amounts of data on the responses of the authorities to the disaster and their programmes of recovery, but never encouraged academic evaluation of policy, although it ensured that the scientific aspects of the eruption and earthquake were meticulously recorded and published. In this paper we remedy this situation by discussing the details of the immediate response to the emergency and the ways in which the island recovered in its aftermath. The study is based not only on archival sources and demographic and economic data, but also on detailed interviews with survivors some of whom were also decision makers. We argue that response, recovery and rehabilitation were generally highly successful and assess the lessons of the 1957/58 emergency which are relevant to future geophysical disasters in Faial and the wider Azores. Since the 1974 revolution Portugal has been a democratic state. We conclude that both the legislation and the civil defence infrastructure, necessary to achieve a similarly strong and successful response, are in place today.

  14. Rupture, waves and earthquakes.

    Science.gov (United States)

    Uenishi, Koji

    2017-01-01

    Normally, an earthquake is considered as a phenomenon of wave energy radiation by rupture (fracture) of solid Earth. However, the physics of dynamic process around seismic sources, which may play a crucial role in the occurrence of earthquakes and generation of strong waves, has not been fully understood yet. Instead, much of former investigation in seismology evaluated earthquake characteristics in terms of kinematics that does not directly treat such dynamic aspects and usually excludes the influence of high-frequency wave components over 1 Hz. There are countless valuable research outcomes obtained through this kinematics-based approach, but "extraordinary" phenomena that are difficult to be explained by this conventional description have been found, for instance, on the occasion of the 1995 Hyogo-ken Nanbu, Japan, earthquake, and more detailed study on rupture and wave dynamics, namely, possible mechanical characteristics of (1) rupture development around seismic sources, (2) earthquake-induced structural failures and (3) wave interaction that connects rupture (1) and failures (2), would be indispensable.

  15. Incorporating human-triggered earthquake risks into energy and water policies

    Science.gov (United States)

    Klose, C. D.; Seeber, L.; Jacob, K. H.

    2010-12-01

    A comprehensive understanding of earthquake risks in urbanized regions requires an accurate assessment of both urban vulnerabilities and hazards from earthquakes, including ones whose timing might be affected by human activities. Socioeconomic risks associated with human-triggered earthquakes are often misconstrued and receive little scientific, legal, and public attention. Worldwide, more than 200 damaging earthquakes, associated with industrialization and urbanization, were documented since the 20th century. Geomechanical pollution due to large-scale geoengineering activities can advance the clock of earthquakes, trigger new seismic events or even shot down natural background seismicity. Activities include mining, hydrocarbon production, fluid injections, water reservoir impoundments and deep-well geothermal energy production. This type of geohazard has impacts on human security on a regional and national level. Some planned or considered future engineering projects raise particularly strong concerns about triggered earthquakes, such as for instance, sequestration of carbon dioxide by injecting it deep underground and large-scale natural gas production in the Marcellus shale in the Appalacian basin. Worldwide examples of earthquakes are discussed, including their associated losses of human life and monetary losses (e.g., 1989 Newcastle and Volkershausen earthquakes, 2001 Killari earthquake, 2006 Basel earthquake, 2010 Wenchuan earthquake). An overview is given on global statistics of human-triggered earthquakes, including depths and time delay of triggering. Lastly, strategies are described, including risk mitigation measures such as urban planning adaptations and seismic hazard mapping.

  16. Recovering from the ShakeOut earthquake

    Science.gov (United States)

    Wein, Anne; Johnson, Laurie; Bernknopf, Richard

    2011-01-01

    Recovery from an earthquake like the M7.8 ShakeOut Scenario will be a major endeavor taking many years to complete. Hundreds of Southern California municipalities will be affected; most lack recovery plans or previous disaster experience. To support recovery planning this paper 1) extends the regional ShakeOut Scenario analysis into the recovery period using a recovery model, 2) localizes analyses to identify longer-term impacts and issues in two communities, and 3) considers the regional context of local recovery.Key community insights about preparing for post-disaster recovery include the need to: geographically diversify city procurement; set earthquake mitigation priorities for critical infrastructure (e.g., airport), plan to replace mobile homes with earthquake safety measures, consider post-earthquake redevelopment opportunities ahead of time, and develop post-disaster recovery management and governance structures. This work also showed that communities with minor damages are still sensitive to regional infrastructure damages and their potential long-term impacts on community recovery. This highlights the importance of community and infrastructure resilience strategies as well.

  17. Earthquakes and Earthquake Engineering. LC Science Tracer Bullet.

    Science.gov (United States)

    Buydos, John F., Comp.

    An earthquake is a shaking of the ground resulting from a disturbance in the earth's interior. Seismology is the (1) study of earthquakes; (2) origin, propagation, and energy of seismic phenomena; (3) prediction of these phenomena; and (4) investigation of the structure of the earth. Earthquake engineering or engineering seismology includes the…

  18. Two hundred years of magma transport and storage at Kīlauea Volcano, Hawai'i, 1790-2008

    Science.gov (United States)

    Wright, Thomas L.; Klein, Fred W.

    2014-01-01

    This publication summarizes the evolution of the internal plumbing of Kīlauea Volcano on the Island of Hawaiʻi from the first documented eruption in 1790 to the explosive eruption of March 2008 in Halemaʻumaʻu Crater. For the period before the founding of the Hawaiian Volcano Observatory in 1912, we rely on written observations of eruptive activity, earthquake swarms, and periodic draining of magma from the lava lake present in Kīlauea Caldera. After 1912 the written observations are supplemented by continuous measurement of tilting of the ground at Kīlauea’s summit and by a continuous instrumental record of earthquakes, both measurements made during 1912–56 by a single pendulum seismometer housed on the northeast edge of Kīlauea’s summit. Interpretations become more robust following the installation of seismic and deformation networks in the 1960s. A major advance in the 1990s was the ability to continuously record and telemeter ground deformation to allow its precise correlation with seismic activity before and after eruptions, intrusions, and large earthquakes.

  19. Testing earthquake source inversion methodologies

    KAUST Repository

    Page, Morgan T.; Mai, Paul Martin; Schorlemmer, Danijel

    2011-01-01

    Source Inversion Validation Workshop; Palm Springs, California, 11-12 September 2010; Nowadays earthquake source inversions are routinely performed after large earthquakes and represent a key connection between recorded seismic and geodetic data

  20. Earthquakes; May-June 1982

    Science.gov (United States)

    Person, W.J.

    1982-01-01

    There were four major earthquakes (7.0-7.9) during this reporting period: two struck in Mexico, one in El Salvador, and one in teh Kuril Islands. Mexico, El Salvador, and China experienced fatalities from earthquakes.

  1. An interdisciplinary approach to study Pre-Earthquake processes

    Science.gov (United States)

    Ouzounov, D.; Pulinets, S. A.; Hattori, K.; Taylor, P. T.

    2017-12-01

    We will summarize a multi-year research effort on wide-ranging observations of pre-earthquake processes. Based on space and ground data we present some new results relevant to the existence of pre-earthquake signals. Over the past 15-20 years there has been a major revival of interest in pre-earthquake studies in Japan, Russia, China, EU, Taiwan and elsewhere. Recent large magnitude earthquakes in Asia and Europe have shown the importance of these various studies in the search for earthquake precursors either for forecasting or predictions. Some new results were obtained from modeling of the atmosphere-ionosphere connection and analyses of seismic records (foreshocks /aftershocks), geochemical, electromagnetic, and thermodynamic processes related to stress changes in the lithosphere, along with their statistical and physical validation. This cross - disciplinary approach could make an impact on our further understanding of the physics of earthquakes and the phenomena that precedes their energy release. We also present the potential impact of these interdisciplinary studies to earthquake predictability. A detail summary of our approach and that of several international researchers will be part of this session and will be subsequently published in a new AGU/Wiley volume. This book is part of the Geophysical Monograph series and is intended to show the variety of parameters seismic, atmospheric, geochemical and historical involved is this important field of research and will bring this knowledge and awareness to a broader geosciences community.

  2. Modernization of the USGS Hawaiian Volcano Observatory Seismic Processing Infrastructure

    Science.gov (United States)

    Antolik, L.; Shiro, B.; Friberg, P. A.

    2016-12-01

    The USGS Hawaiian Volcano Observatory (HVO) operates a Tier 1 Advanced National Seismic System (ANSS) seismic network to monitor, characterize, and report on volcanic and earthquake activity in the State of Hawaii. Upgrades at the observatory since 2009 have improved the digital telemetry network, computing resources, and seismic data processing with the adoption of the ANSS Quake Management System (AQMS) system. HVO aims to build on these efforts by further modernizing its seismic processing infrastructure and strengthen its ability to meet ANSS performance standards. Most notably, this will also allow HVO to support redundant systems, both onsite and offsite, in order to provide better continuity of operation during intermittent power and network outages. We are in the process of implementing a number of upgrades and improvements on HVO's seismic processing infrastructure, including: 1) Virtualization of AQMS physical servers; 2) Migration of server operating systems from Solaris to Linux; 3) Consolidation of AQMS real-time and post-processing services to a single server; 4) Upgrading database from Oracle 10 to Oracle 12; and 5) Upgrading to the latest Earthworm and AQMS software. These improvements will make server administration more efficient, minimize hardware resources required by AQMS, simplify the Oracle replication setup, and provide better integration with HVO's existing state of health monitoring tools and backup system. Ultimately, it will provide HVO with the latest and most secure software available while making the software easier to deploy and support.

  3. Characteristics of Offshore Hawai';i Island Seismicity and Velocity Structure, including Lo';ihi Submarine Volcano

    Science.gov (United States)

    Merz, D. K.; Caplan-Auerbach, J.; Thurber, C. H.

    2013-12-01

    The Island of Hawai';i is home to the most active volcanoes in the Hawaiian Islands. The island's isolated nature, combined with the lack of permanent offshore seismometers, creates difficulties in recording small magnitude earthquakes with accuracy. This background offshore seismicity is crucial in understanding the structure of the lithosphere around the island chain, the stresses on the lithosphere generated by the weight of the islands, and how the volcanoes interact with each other offshore. This study uses the data collected from a 9-month deployment of a temporary ocean bottom seismometer (OBS) network fully surrounding Lo';ihi volcano. This allowed us to widen the aperture of earthquake detection around the Big Island, lower the magnitude detection threshold, and better constrain the hypocentral depths of offshore seismicity that occurs between the OBS network and the Hawaii Volcano Observatory's land based network. Although this study occurred during a time of volcanic quiescence for Lo';ihi, it establishes a basis for background seismicity of the volcano. More than 480 earthquakes were located using the OBS network, incorporating data from the HVO network where possible. Here we present relocated hypocenters using the double-difference earthquake location algorithm HypoDD (Waldhauser & Ellsworth, 2000), as well as tomographic images for a 30 km square area around the summit of Lo';ihi. Illuminated by using the double-difference earthquake location algorithm HypoDD (Waldhauser & Ellsworth, 2000), offshore seismicity during this study is punctuated by events locating in the mantle fault zone 30-50km deep. These events reflect rupture on preexisting faults in the lower lithosphere caused by stresses induced by volcano loading and flexure of the Pacific Plate (Wolfe et al., 2004; Pritchard et al., 2007). Tomography was performed using the double-difference seismic tomography method TomoDD (Zhang & Thurber, 2003) and showed overall velocities to be slower than

  4. Sensing the earthquake

    Science.gov (United States)

    Bichisao, Marta; Stallone, Angela

    2017-04-01

    Making science visual plays a crucial role in the process of building knowledge. In this view, art can considerably facilitate the representation of the scientific content, by offering a different perspective on how a specific problem could be approached. Here we explore the possibility of presenting the earthquake process through visual dance. From a choreographer's point of view, the focus is always on the dynamic relationships between moving objects. The observed spatial patterns (coincidences, repetitions, double and rhythmic configurations) suggest how objects organize themselves in the environment and what are the principles underlying that organization. The identified set of rules is then implemented as a basis for the creation of a complex rhythmic and visual dance system. Recently, scientists have turned seismic waves into sound and animations, introducing the possibility of "feeling" the earthquakes. We try to implement these results into a choreographic model with the aim to convert earthquake sound to a visual dance system, which could return a transmedia representation of the earthquake process. In particular, we focus on a possible method to translate and transfer the metric language of seismic sound and animations into body language. The objective is to involve the audience into a multisensory exploration of the earthquake phenomenon, through the stimulation of the hearing, eyesight and perception of the movements (neuromotor system). In essence, the main goal of this work is to develop a method for a simultaneous visual and auditory representation of a seismic event by means of a structured choreographic model. This artistic representation could provide an original entryway into the physics of earthquakes.

  5. Volcanoes in the Classroom--an Explosive Learning Experience.

    Science.gov (United States)

    Thompson, Susan A.; Thompson, Keith S.

    1996-01-01

    Presents a unit on volcanoes for third- and fourth-grade students. Includes demonstrations; video presentations; building a volcano model; and inviting a scientist, preferably a vulcanologist, to share his or her expertise with students. (JRH)

  6. Volcanostratigraphic Approach for Evaluation of Geothermal Potential in Galunggung Volcano

    Science.gov (United States)

    Ramadhan, Q. S.; Sianipar, J. Y.; Pratopo, A. K.

    2016-09-01

    he geothermal systems in Indonesia are primarily associated with volcanoes. There are over 100 volcanoes located on Sumatra, Java, and in the eastern part of Indonesia. Volcanostratigraphy is one of the methods that is used in the early stage for the exploration of volcanic geothermal system to identify the characteristics of the volcano. The stratigraphy of Galunggung Volcano is identified based on 1:100.000 scale topographic map of Tasikmalaya sheet, 1:50.000 scale topographic map and also geological map. The schematic flowchart for evaluation of geothermal exploration is used to interpret and evaluate geothermal potential in volcanic regions. Volcanostratigraphy study has been done on Galunggung Volcano and Talaga Bodas Volcano, West Java, Indonesia. Based on the interpretation of topographic map and analysis of the dimension, rock composition, age and stress regime, we conclude that both Galunggung Volcano and Talaga Bodas Volcano have a geothermal resource potential that deserve further investigation.

  7. Turkish Children's Ideas about Earthquakes

    Science.gov (United States)

    Simsek, Canan Lacin

    2007-01-01

    Earthquake, a natural disaster, is among the fundamental problems of many countries. If people know how to protect themselves from earthquake and arrange their life styles in compliance with this, damage they will suffer will reduce to that extent. In particular, a good training regarding earthquake to be received in primary schools is considered…

  8. Earthquakes, May-June 1991

    Science.gov (United States)

    Person, W.J.

    1992-01-01

    One major earthquake occurred during this reporting period. This was a magntidue 7.1 in Indonesia (Minahassa Peninsula) on June 20. Earthquake-related deaths were reported in the Western Caucasus (Georgia, USSR) on May 3 and June 15. One earthquake-related death was also reported El Salvador on June 21. 

  9. The 1976 Tangshan earthquake

    Science.gov (United States)

    Fang, Wang

    1979-01-01

    The Tangshan earthquake of 1976 was one of the largest earthquakes in recent years. It occurred on July 28 at 3:42 a.m, Beijing (Peking) local time, and had magnitude 7.8, focal depth of 15 kilometers, and an epicentral intensity of XI on the New Chinese Seismic Intensity Scale; it caused serious damage and loss of life in this densely populated industrial city. Now, with the help of people from all over China, the city of Tangshan is being rebuild. 

  10. Multi-Sensor Observations of Earthquake Related Atmospheric Signals over Major Geohazard Validation Sites

    Science.gov (United States)

    Ouzounov, D.; Pulinets, S.; Davindenko, D.; Hattori, K.; Kafatos, M.; Taylor, P.

    2012-01-01

    We are conducting a scientific validation study involving multi-sensor observations in our investigation of phenomena preceding major earthquakes. Our approach is based on a systematic analysis of several atmospheric and environmental parameters, which we found, are associated with the earthquakes, namely: thermal infrared radiation, outgoing long-wavelength radiation, ionospheric electron density, and atmospheric temperature and humidity. For first time we applied this approach to selected GEOSS sites prone to earthquakes or volcanoes. This provides a new opportunity to cross validate our results with the dense networks of in-situ and space measurements. We investigated two different seismic aspects, first the sites with recent large earthquakes, viz.- Tohoku-oki (M9, 2011, Japan) and Emilia region (M5.9, 2012,N. Italy). Our retrospective analysis of satellite data has shown the presence of anomalies in the atmosphere. Second, we did a retrospective analysis to check the re-occurrence of similar anomalous behavior in atmosphere/ionosphere over three regions with distinct geological settings and high seismicity: Taiwan, Japan and Kamchatka, which include 40 major earthquakes (M>5.9) for the period of 2005-2009. We found anomalous behavior before all of these events with no false negatives; false positives were less then 10%. Our initial results suggest that multi-instrument space-borne and ground observations show a systematic appearance of atmospheric anomalies near the epicentral area that could be explained by a coupling between the observed physical parameters and earthquake preparation processes.

  11. Expanding Horizons in Mitigating Earthquake Related Disasters in Urban Areas: Global Development of Real-Time Seismology

    OpenAIRE

    Utkucu, Murat; Küyük, Hüseyin Serdar; Demir, İsmail Hakkı

    2016-01-01

    Abstract Real-time seismology is a newly developing alternative approach in seismology to mitigate earthquake hazard. It exploits up-to-date advances in seismic instrument technology, data acquisition, digital communications and computer systems for quickly transforming data into earthquake information in real-time to reduce earthquake losses and its impact on social and economic life in the earthquake prone densely populated urban and industrial areas.  Real-time seismology systems are not o...

  12. Food, water, and fault lines: Remote sensing opportunities for earthquake-response management of agricultural water

    International Nuclear Information System (INIS)

    Rodriguez, Jenna; Ustin, Susan; Sandoval-Solis, Samuel; O'Geen, Anthony Toby

    2016-01-01

    Earthquakes often cause destructive and unpredictable changes that can affect local hydrology (e.g. groundwater elevation or reduction) and thus disrupt land uses and human activities. Prolific agricultural regions overlie seismically active areas, emphasizing the importance to improve our understanding and monitoring of hydrologic and agricultural systems following a seismic event. A thorough data collection is necessary for adequate post-earthquake crop management response; however, the large spatial extent of earthquake's impact makes challenging the collection of robust data sets for identifying locations and magnitude of these impacts. Observing hydrologic responses to earthquakes is not a novel concept, yet there is a lack of methods and tools for assessing earthquake's impacts upon the regional hydrology and agricultural systems. The objective of this paper is to describe how remote sensing imagery, methods and tools allow detecting crop responses and damage incurred after earthquakes because a change in the regional hydrology. Many remote sensing datasets are long archived with extensive coverage and with well-documented methods to assess plant-water relations. We thus connect remote sensing of plant water relations to its utility in agriculture using a post-earthquake agrohydrologic remote sensing (PEARS) framework; specifically in agro-hydrologic relationships associated with recent earthquake events that will lead to improved water management. - Highlights: • Remote sensing to improve agricultural disaster management • Introduce post-earthquake agrohydrologic remote sensing (PEARS) framework • Apply PEARS framework to 2010 Maule Earthquake in Central Chile

  13. Food, water, and fault lines: Remote sensing opportunities for earthquake-response management of agricultural water

    Energy Technology Data Exchange (ETDEWEB)

    Rodriguez, Jenna, E-mail: jmmartin@ucdavis.edu; Ustin, Susan; Sandoval-Solis, Samuel; O' Geen, Anthony Toby

    2016-09-15

    Earthquakes often cause destructive and unpredictable changes that can affect local hydrology (e.g. groundwater elevation or reduction) and thus disrupt land uses and human activities. Prolific agricultural regions overlie seismically active areas, emphasizing the importance to improve our understanding and monitoring of hydrologic and agricultural systems following a seismic event. A thorough data collection is necessary for adequate post-earthquake crop management response; however, the large spatial extent of earthquake's impact makes challenging the collection of robust data sets for identifying locations and magnitude of these impacts. Observing hydrologic responses to earthquakes is not a novel concept, yet there is a lack of methods and tools for assessing earthquake's impacts upon the regional hydrology and agricultural systems. The objective of this paper is to describe how remote sensing imagery, methods and tools allow detecting crop responses and damage incurred after earthquakes because a change in the regional hydrology. Many remote sensing datasets are long archived with extensive coverage and with well-documented methods to assess plant-water relations. We thus connect remote sensing of plant water relations to its utility in agriculture using a post-earthquake agrohydrologic remote sensing (PEARS) framework; specifically in agro-hydrologic relationships associated with recent earthquake events that will lead to improved water management. - Highlights: • Remote sensing to improve agricultural disaster management • Introduce post-earthquake agrohydrologic remote sensing (PEARS) framework • Apply PEARS framework to 2010 Maule Earthquake in Central Chile.

  14. Radon surveys and monitoring at active volcanoes: an open window on deep hydrothermal systems and their dynamics

    Science.gov (United States)

    Cigolini, Corrado; Laiolo, Marco; Coppola, Diego

    2017-04-01

    The behavior of fluids in hydrothermal systems is critical in volcano monitoring and geothermal prospecting. Analyzing the time series of radon emissions on active volcanoes is strategic for detecting and interpreting precursory signals of changes in volcanic activity, eventually leading to eruptions. Radon is a radioactive gas generated from the decay of U bearing rocks, soils and magmas. Although radon has been regarded as a potential precursor of earthquakes, radon anomalies appear to be better suited to forecast volcanic eruptions since we know where paroxysms may occur and we can follow the evolution of volcanic activity. Radon mapping at active volcanoes is also a reliable tool to assess diffuse and concentrated degassing as well as efficiently detecting earthquake-volcano interactions. Systematic radon monitoring has been shown to be a key factor for evaluating the rise of volcanic and hydrothermal fluids. In fact, the decay properties of radon, the duration of radon anomalies together with sampling rates may be cross-checked with the chemistry of hydrothermal fluids (and their transport properties) to constrain fluids ascent rates and to infer the permeability and porosity of rocks in sectors surrounding the active conduits. We hereby further discuss the data of radon surveys and monitoring at Somma-Vesuvius, Stromboli and La Soufrière (Guadeloupe, Lesser Antilles). The integrated analysis of seismic and geochemical data, including radon emissions, may be successfully used in testing temperature distributions and variations of porosity and permeability in volcanic hydrothermal systems and can be used as a proxy to analyze geothermal reservoirs.

  15. The mechanism of earthquake

    Science.gov (United States)

    Lu, Kunquan; Cao, Zexian; Hou, Meiying; Jiang, Zehui; Shen, Rong; Wang, Qiang; Sun, Gang; Liu, Jixing

    2018-03-01

    The physical mechanism of earthquake remains a challenging issue to be clarified. Seismologists used to attribute shallow earthquake to the elastic rebound of crustal rocks. The seismic energy calculated following the elastic rebound theory and with the data of experimental results upon rocks, however, shows a large discrepancy with measurement — a fact that has been dubbed as “the heat flow paradox”. For the intermediate-focus and deep-focus earthquakes, both occurring in the region of the mantle, there is not reasonable explanation either. This paper will discuss the physical mechanism of earthquake from a new perspective, starting from the fact that both the crust and the mantle are discrete collective system of matters with slow dynamics, as well as from the basic principles of physics, especially some new concepts of condensed matter physics emerged in the recent years. (1) Stress distribution in earth’s crust: Without taking the tectonic force into account, according to the rheological principle of “everything flows”, the normal stress and transverse stress must be balanced due to the effect of gravitational pressure over a long period of time, thus no differential stress in the original crustal rocks is to be expected. The tectonic force is successively transferred and accumulated via stick-slip motions of rock blocks to squeeze the fault gouge and then exerted upon other rock blocks. The superposition of such additional lateral tectonic force and the original stress gives rise to the real-time stress in crustal rocks. The mechanical characteristics of fault gouge are different from rocks as it consists of granular matters. The elastic moduli of the fault gouges are much less than those of rocks, and they become larger with increasing pressure. This peculiarity of the fault gouge leads to a tectonic force increasing with depth in a nonlinear fashion. The distribution and variation of the tectonic stress in the crust are specified. (2) The

  16. Volcano Geodesy: Recent developments and future challenges

    Science.gov (United States)

    Fernandez, Jose F.; Pepe, Antonio; Poland, Michael; Sigmundsson, Freysteinn

    2017-01-01

    Ascent of magma through Earth's crust is normally associated with, among other effects, ground deformation and gravity changes. Geodesy is thus a valuable tool for monitoring and hazards assessment during volcanic unrest, and it provides valuable data for exploring the geometry and volume of magma plumbing systems. Recent decades have seen an explosion in the quality and quantity of volcano geodetic data. New datasets (some made possible by regional and global scientific initiatives), as well as new analysis methods and modeling practices, have resulted in important changes to our understanding of the geodetic characteristics of active volcanism and magmatic processes, from the scale of individual eruptive vents to global compilations of volcano deformation. Here, we describe some of the recent developments in volcano geodesy, both in terms of data and interpretive tools, and discuss the role of international initiatives in meeting future challenges for the field.

  17. Soil radon response around an active volcano

    International Nuclear Information System (INIS)

    Segovia, N.; Valdes, C.; Pena, P.; Mena, M.; Tamez, E.

    2001-01-01

    Soil radon behavior related to the volcanic eruptive period 1997-1999 of Popocatepetl volcano has been studied as a function of the volcanic activity. Since the volcano is located 60 km from Mexico City, the risk associated with an explosive eruptive phase is high and an intense surveillance program has been implemented. Previous studies in this particular volcano showed soil radon pulses preceding the initial phase of the eruption. The radon survey was performed with LR-115 track detectors at a shallow depth and the effect of the soil moisture during the rainy season has been observed on the detectors response. In the present state of the volcanic activity the soil radon behavior has shown more stability than in previous eruptive stages

  18. 2014 mainshock-aftershock activity versus earthquake swarms in West\

    Czech Academy of Sciences Publication Activity Database

    Jakoubková, Hana; Horálek, Josef; Fischer, T.

    2018-01-01

    Roč. 175, č. 1 (2018), s. 109-131 ISSN 0033-4553 R&D Projects: GA ČR GAP210/12/2336; GA MŠk(CZ) LM2015079 Institutional support: RVO:67985530 Keywords : West Bohemia/Vogtland * earthquake swarms * mainshock-aftershock sequence * total seismic moment * statistical characteristics of earthquake activities Subject RIV: DC - Siesmology, Volcanology, Earth Structure Impact factor: 1.591, year: 2016

  19. Far-field coseismic ionospheric disturbances of Tohoku earthquake

    Czech Academy of Sciences Publication Activity Database

    Krasnov, V. M.; Drobzheva, Ya. V.; Chum, Jaroslav

    2015-01-01

    Roč. 135, December (2015), s. 12-21 ISSN 1364-6826 R&D Projects: GA ČR(CZ) GC15-07281J Institutional support: RVO:68378289 Keywords : earthquake * infrasonic waves * ionospheric disturbances * infrasound triggered by the earthquake * co-seismic ionospheric perturbations * modeling * remote sensing Subject RIV: DG - Athmosphere Sciences, Meteorology Impact factor: 1.463, year: 2015 http://www.sciencedirect.com/science/article/pii/S1364682615300584

  20. Earthquake Safety Tips in the Classroom

    Science.gov (United States)

    Melo, M. O.; Maciel, B. A. P. C.; Neto, R. P.; Hartmann, R. P.; Marques, G.; Gonçalves, M.; Rocha, F. L.; Silveira, G. M.

    2014-12-01

    The catastrophes induced by earthquakes are among the most devastating ones, causing an elevated number of human losses and economic damages. But, we have to keep in mind that earthquakes don't kill people, buildings do. Earthquakes can't be predicted and the only way of dealing with their effects is to teach the society how to be prepared for them, and how to deal with their consequences. In spite of being exposed to moderate and large earthquakes, most of the Portuguese are little aware of seismic risk, mainly due to the long recurrence intervals between strong events. The acquisition of safe and correct attitudes before, during and after an earthquake is relevant for human security. Children play a determinant role in the establishment of a real and long-lasting "culture of prevention", both through action and new attitudes. On the other hand, when children assume correct behaviors, their relatives often change their incorrect behaviors to mimic the correct behaviors of their kids. In the framework of a Parents-in-Science initiative, we started with bi-monthly sessions for children aged 5 - 6 years old and 9 - 10 years old. These sessions, in which parents, teachers and high-school students participate, became part of the school's permanent activities. We start by a short introduction to the Earth and to earthquakes by story telling and by using simple science activities to trigger children curiosity. With safety purposes, we focus on how crucial it is to know basic information about themselves and to define, with their families, an emergency communications plan, in case family members are separated. Using a shaking table we teach them how to protect themselves during an earthquake. We then finish with the preparation on an individual emergency kit. This presentation will highlight the importance of encouraging preventive actions in order to reduce the impact of earthquakes on society. This project is developed by science high-school students and teachers, in

  1. Predicting the Timing and Location of the next Hawaiian Volcano

    Science.gov (United States)

    Russo, Joseph; Mattox, Stephen; Kildau, Nicole

    2010-01-01

    The wealth of geologic data on Hawaiian volcanoes makes them ideal for study by middle school students. In this paper the authors use existing data on the age and location of Hawaiian volcanoes to predict the location of the next Hawaiian volcano and when it will begin to grow on the floor of the Pacific Ocean. An inquiry-based lesson is also…

  2. Interdisciplinary studies of eruption at Chaiten Volcano, Chile

    Science.gov (United States)

    John S. Pallister; Jon J. Major; Thomas C. Pierson; Richard P. Hoblitt; Jacob B. Lowenstern; John C. Eichelberger; Lara. Luis; Hugo Moreno; Jorge Munoz; Jonathan M. Castro; Andres Iroume; Andrea Andreoli; Julia Jones; Fred Swanson; Charlie Crisafulli

    2010-01-01

    There was keen interest within the volcanology community when the first large eruption of high-silica rhyolite since that of Alaska's Novarupta volcano in 1912 began on 1 May 2008 at Chaiten volcano, southern Chile, a 3-kilometer-diameter caldera volcano with a prehistoric record of rhyolite eruptions. Vigorous explosions occurred through 8 May 2008, after which...

  3. How Do Volcanoes Affect Human Life? Integrated Unit.

    Science.gov (United States)

    Dayton, Rebecca; Edwards, Carrie; Sisler, Michelle

    This packet contains a unit on teaching about volcanoes. The following question is addressed: How do volcanoes affect human life? The unit covers approximately three weeks of instruction and strives to present volcanoes in an holistic form. The five subject areas of art, language arts, mathematics, science, and social studies are integrated into…

  4. Living with Volcanoes: Year Eleven Teaching Resource Unit.

    Science.gov (United States)

    Le Heron, Kiri; Andrews, Jill; Hooks, Stacey; Larnder, Michele; Le Heron, Richard

    2000-01-01

    Presents a unit on volcanoes and experiences with volcanoes that helps students develop geography skills. Focuses on four volcanoes: (1) Rangitoto Island; (2) Lake Pupuke; (3) Mount Smart; and (4) One Tree Hill. Includes an answer sheet and resources to use with the unit. (CMK)

  5. Volcanoes muon imaging using Cherenkov telescopes

    International Nuclear Information System (INIS)

    Catalano, O.; Del Santo, M.; Mineo, T.; Cusumano, G.; Maccarone, M.C.; Pareschi, G.

    2016-01-01

    A detailed understanding of a volcano inner structure is one of the key-points for the volcanic hazards evaluation. To this aim, in the last decade, geophysical radiography techniques using cosmic muon particles have been proposed. By measuring the differential attenuation of the muon flux as a function of the amount of rock crossed along different directions, it is possible to determine the density distribution of the interior of a volcano. Up to now, a number of experiments have been based on the detection of the muon tracks crossing hodoscopes, made up of scintillators or nuclear emulsion planes. Using telescopes based on the atmospheric Cherenkov imaging technique, we propose a new approach to study the interior of volcanoes detecting of the Cherenkov light produced by relativistic cosmic-ray muons that survive after crossing the volcano. The Cherenkov light produced along the muon path is imaged as a typical annular pattern containing all the essential information to reconstruct particle direction and energy. Our new approach offers the advantage of a negligible background and an improved spatial resolution. To test the feasibility of our new method, we have carried out simulations with a toy-model based on the geometrical parameters of ASTRI SST-2M, i.e. the imaging atmospheric Cherenkov telescope currently under installation onto the Etna volcano. Comparing the results of our simulations with previous experiments based on particle detectors, we gain at least a factor of 10 in sensitivity. The result of this study shows that we resolve an empty cylinder with a radius of about 100 m located inside a volcano in less than 4 days, which implies a limit on the magma velocity of 5 m/h.

  6. Volcanoes muon imaging using Cherenkov telescopes

    Energy Technology Data Exchange (ETDEWEB)

    Catalano, O. [INAF, Istituto di Astrofisica Spaziale e Fisica cosmica di Palermo, via U. La Malfa 153, I-90146 Palermo (Italy); Del Santo, M., E-mail: melania@ifc.inaf.it [INAF, Istituto di Astrofisica Spaziale e Fisica cosmica di Palermo, via U. La Malfa 153, I-90146 Palermo (Italy); Mineo, T.; Cusumano, G.; Maccarone, M.C. [INAF, Istituto di Astrofisica Spaziale e Fisica cosmica di Palermo, via U. La Malfa 153, I-90146 Palermo (Italy); Pareschi, G. [INAF Osservatorio Astronomico di Brera, Via E. Bianchi 46, I-23807, Merate (Italy)

    2016-01-21

    A detailed understanding of a volcano inner structure is one of the key-points for the volcanic hazards evaluation. To this aim, in the last decade, geophysical radiography techniques using cosmic muon particles have been proposed. By measuring the differential attenuation of the muon flux as a function of the amount of rock crossed along different directions, it is possible to determine the density distribution of the interior of a volcano. Up to now, a number of experiments have been based on the detection of the muon tracks crossing hodoscopes, made up of scintillators or nuclear emulsion planes. Using telescopes based on the atmospheric Cherenkov imaging technique, we propose a new approach to study the interior of volcanoes detecting of the Cherenkov light produced by relativistic cosmic-ray muons that survive after crossing the volcano. The Cherenkov light produced along the muon path is imaged as a typical annular pattern containing all the essential information to reconstruct particle direction and energy. Our new approach offers the advantage of a negligible background and an improved spatial resolution. To test the feasibility of our new method, we have carried out simulations with a toy-model based on the geometrical parameters of ASTRI SST-2M, i.e. the imaging atmospheric Cherenkov telescope currently under installation onto the Etna volcano. Comparing the results of our simulations with previous experiments based on particle detectors, we gain at least a factor of 10 in sensitivity. The result of this study shows that we resolve an empty cylinder with a radius of about 100 m located inside a volcano in less than 4 days, which implies a limit on the magma velocity of 5 m/h.

  7. The Relationship of Acculturation Strategies to Resilience: The Moderating Impact of Social Support among Qiang Ethnicity following the 2008 Chinese Earthquake.

    Science.gov (United States)

    Han, Li; Berry, John W; Zheng, Yong

    2016-01-01

    International research has mostly confirmed the positive association between acculturation strategies and resilience in ethnic groups, but the mediating and moderating mechanisms underlying the rela