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

Science.gov (United States)

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

2013-12-01

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

Summary of Great East Japan Earthquake response at Onagawa Nuclear Power Station and further safety improvement measures

International Nuclear Information System (INIS)

Sato, Toru

2013-01-01

A large earthquake occurred on March 11, 2011 and tsunami was generated following it. The East Japan suffered serious damage by the earthquake and tsunami. This is called the Great East Japan Earthquake. Onagawa Nuclear Power Station (NPS) is located closest to the epicenter of Great East Japan Earthquake. We experienced intense shake by the earthquake and some flooding from the tsunami, however, we have succeeded safely cold shutdown of the reactors. In this paper, we introduce summary of Great East Japan Earthquake response a Onagawa NPS and safety improvement measures which are based on both experience of Onagawa NPS and lesson from Fukushima Daiichi NPS accident. (author)

1964 Great Alaska Earthquake: a photographic tour of Anchorage, Alaska

Science.gov (United States)

Thoms, Evan E.; Haeussler, Peter J.; Anderson, Rebecca D.; McGimsey, Robert G.

2014-01-01

On March 27, 1964, at 5:36 p.m., a magnitude 9.2 earthquake, the largest recorded earthquake in U.S. history, struck southcentral Alaska (fig. 1). The Great Alaska Earthquake (also known as the Good Friday Earthquake) occurred at a pivotal time in the history of earth science, and helped lead to the acceptance of plate tectonic theory (Cox, 1973; Brocher and others, 2014). All large subduction zone earthquakes are understood through insights learned from the 1964 event, and observations and interpretations of the earthquake have influenced the design of infrastructure and seismic monitoring systems now in place. The earthquake caused extensive damage across the State, and triggered local tsunamis that devastated the Alaskan towns of Whittier, Valdez, and Seward. In Anchorage, the main cause of damage was ground shaking, which lasted approximately 4.5 minutes. Many buildings could not withstand this motion and were damaged or collapsed even though their foundations remained intact. More significantly, ground shaking triggered a number of landslides along coastal and drainage valley bluffs underlain by the Bootlegger Cove Formation, a composite of facies containing variably mixed gravel, sand, silt, and clay which were deposited over much of upper Cook Inlet during the Late Pleistocene (Ulery and others, 1983). Cyclic (or strain) softening of the more sensitive clay facies caused overlying blocks of soil to slide sideways along surfaces dipping by only a few degrees. This guide is the document version of an interactive web map that was created as part of the commemoration events for the 50th anniversary of the 1964 Great Alaska Earthquake. It is accessible at the U.S. Geological Survey (USGS) Alaska Science Center website: http://alaska.usgs.gov/announcements/news/1964Earthquake/. The website features a map display with suggested tour stops in Anchorage, historical photographs taken shortly after the earthquake, repeat photography of selected sites, scanned documents

Geological evidence of recurrent great Kanto earthquakes at the Miura Peninsula, Japan

Science.gov (United States)

Shimazaki, K.; Kim, H. Y.; Chiba, T.; Satake, K.

2011-12-01

The Tokyo metropolitan area's well-documented earthquake history is dominated by the 1703 and 1923 great Kanto earthquakes produced by slip on the boundary between the subducting Philippine Sea plate and the overlying plate. Both earthquakes caused ˜1.5 m of uplift at the Miura Peninsula directly above the inferred fault rupture, and both were followed by tsunamis with heights of ˜5 m. We examined cores ˜2 m long from 8 tidal flat sites at the head of a small bay on the peninsula. The cores penetrated two to four layers of shelly gravel, as much as 0.5 m thick, with abundant shell fragments and mud clasts. The presence of gravel indicates strong tractive currents. Muddy bay deposits that bound the gravel layers show vertical changes in grain size and diatom assemblages consistent with abrupt shoaling at the times of the currents. The changes may further suggest gradual deepening of the bay during the intervals between the strong currents. We infer, based on 137Cs, 14C, and 210Pb dating, that the top two shelly gravel layers represent tsunamis associated with the 1703 and 1923 great Kanto earthquakes, and that the third layer was deposited by a tsunami during an earlier earthquake. The age range of this layer, AD 1060-1400, includes the time of an earthquake that occurred in 1293 according to a historical document. If so, the recurrence interval before the 1703 earthquake was almost twice as long as the interval between the 1703 and 1923 earthquakes.

Great earthquakes along the Western United States continental margin: implications for hazards, stratigraphy and turbidite lithology

Science.gov (United States)

Nelson, C. H.; Gutiérrez Pastor, J.; Goldfinger, C.; Escutia, C.

2012-11-01

We summarize the importance of great earthquakes (Mw ≳ 8) for hazards, stratigraphy of basin floors, and turbidite lithology along the active tectonic continental margins of the Cascadia subduction zone and the northern San Andreas Transform Fault by utilizing studies of swath bathymetry visual core descriptions, grain size analysis, X-ray radiographs and physical properties. Recurrence times of Holocene turbidites as proxies for earthquakes on the Cascadia and northern California margins are analyzed using two methods: (1) radiometric dating (14C method), and (2) relative dating, using hemipelagic sediment thickness and sedimentation rates (H method). The H method provides (1) the best estimate of minimum recurrence times, which are the most important for seismic hazards risk analysis, and (2) the most complete dataset of recurrence times, which shows a normal distribution pattern for paleoseismic turbidite frequencies. We observe that, on these tectonically active continental margins, during the sea-level highstand of Holocene time, triggering of turbidity currents is controlled dominantly by earthquakes, and paleoseismic turbidites have an average recurrence time of ~550 yr in northern Cascadia Basin and ~200 yr along northern California margin. The minimum recurrence times for great earthquakes are approximately 300 yr for the Cascadia subduction zone and 130 yr for the northern San Andreas Fault, which indicates both fault systems are in (Cascadia) or very close (San Andreas) to the early window for another great earthquake. On active tectonic margins with great earthquakes, the volumes of mass transport deposits (MTDs) are limited on basin floors along the margins. The maximum run-out distances of MTD sheets across abyssal-basin floors along active margins are an order of magnitude less (~100 km) than on passive margins (~1000 km). The great earthquakes along the Cascadia and northern California margins cause seismic strengthening of the sediment, which

Modeling Seismic Cycles of Great Megathrust Earthquakes Across the Scales With Focus at Postseismic Phase

Science.gov (United States)

Sobolev, Stephan V.; Muldashev, Iskander A.

2017-12-01

Subduction is substantially multiscale process where the stresses are built by long-term tectonic motions, modified by sudden jerky deformations during earthquakes, and then restored by following multiple relaxation processes. Here we develop a cross-scale thermomechanical model aimed to simulate the subduction process from 1 min to million years' time scale. The model employs elasticity, nonlinear transient viscous rheology, and rate-and-state friction. It generates spontaneous earthquake sequences and by using an adaptive time step algorithm, recreates the deformation process as observed naturally during the seismic cycle and multiple seismic cycles. The model predicts that viscosity in the mantle wedge drops by more than three orders of magnitude during the great earthquake with a magnitude above 9. As a result, the surface velocities just an hour or day after the earthquake are controlled by viscoelastic relaxation in the several hundred km of mantle landward of the trench and not by the afterslip localized at the fault as is currently believed. Our model replicates centuries-long seismic cycles exhibited by the greatest earthquakes and is consistent with the postseismic surface displacements recorded after the Great Tohoku Earthquake. We demonstrate that there is no contradiction between extremely low mechanical coupling at the subduction megathrust in South Chile inferred from long-term geodynamic models and appearance of the largest earthquakes, like the Great Chile 1960 Earthquake.

Great earthquakes along the Western United States continental margin: implications for hazards, stratigraphy and turbidite lithology

Directory of Open Access Journals (Sweden)

C. H. Nelson

2012-11-01

Full Text Available We summarize the importance of great earthquakes (M_w ≳ 8 for hazards, stratigraphy of basin floors, and turbidite lithology along the active tectonic continental margins of the Cascadia subduction zone and the northern San Andreas Transform Fault by utilizing studies of swath bathymetry visual core descriptions, grain size analysis, X-ray radiographs and physical properties. Recurrence times of Holocene turbidites as proxies for earthquakes on the Cascadia and northern California margins are analyzed using two methods: (1 radiometric dating (¹⁴C method, and (2 relative dating, using hemipelagic sediment thickness and sedimentation rates (H method. The H method provides (1 the best estimate of minimum recurrence times, which are the most important for seismic hazards risk analysis, and (2 the most complete dataset of recurrence times, which shows a normal distribution pattern for paleoseismic turbidite frequencies. We observe that, on these tectonically active continental margins, during the sea-level highstand of Holocene time, triggering of turbidity currents is controlled dominantly by earthquakes, and paleoseismic turbidites have an average recurrence time of ~550 yr in northern Cascadia Basin and ~200 yr along northern California margin. The minimum recurrence times for great earthquakes are approximately 300 yr for the Cascadia subduction zone and 130 yr for the northern San Andreas Fault, which indicates both fault systems are in (Cascadia or very close (San Andreas to the early window for another great earthquake.

On active tectonic margins with great earthquakes, the volumes of mass transport deposits (MTDs are limited on basin floors along the margins. The maximum run-out distances of MTD sheets across abyssal-basin floors along active margins are an order of magnitude less (~100 km than on passive margins (~1000 km. The great earthquakes along the Cascadia and northern California margins

Tectonic styles of future earthquakes in Italy as input data for seismic hazard

Science.gov (United States)

Pondrelli, S.; Meletti, C.; Rovida, A.; Visini, F.; D'Amico, V.; Pace, B.

2017-12-01

In a recent elaboration of a new seismogenic zonation and hazard model for Italy, we tried to understand how many indications we have on the tectonic style of future earthquake/rupture. Using all available or recomputed seismic moment tensors for relevant seismic events (Mw starting from 4.5) of the last 100 yrs, first arrival focal mechanisms for less recent earthquakes and also geological data on past activated faults, we collected a database gathering a thousands of data all over the Italian peninsula and regions around it. After several summations of seismic moment tensors, over regular grids of different dimensions and different thicknesses of the seismogenic layer, we applied the same procedure to each of the 50 area sources that were designed in the seismogenic zonation. The results for several seismic zones are very stable, e.g. along the southern Apennines we expect future earthquakes to be mostly extensional, although in the outer part of the chain strike-slip events are possible. In the Northern part of the Apennines we also expect different, opposite tectonic styles for different hypocentral depths. In several zones, characterized by a low seismic moment release, defined for the study region using 1000 yrs of catalog, the next possible tectonic style of future earthquakes is less clear. It is worth to note that for some zones the possible greatest earthquake could be not represented in the available observations. We also add to our analysis the computation of the seismic release rate, computed using a distributed completeness, identified for single great events of the historical seismic catalog for Italy. All these information layers, overlapped and compared, may be used to characterize each new seismogenic zone.

Delphi survey of issues after the Great East Japan Earthquake

International Nuclear Information System (INIS)

Maeda, Yasunobu; Seo, Kami; Motoyoshi, Tadahiro; Okada, Shinya

2011-01-01

The Great East Japan Earthquake on March 11, 2011 has catastrophic impacts on Japan. Japan is currently on the way to recovery. However, as the damage on the country as well as society is so serious, Japanese society is urged to change some systems including hazard management, energy policy, information systems and city planning. These changes are accompanied with social group realignments, thus necessarily followed by various risks. To cope with these risk issues, SRA-Japan established the special research committee for the Great East Japan Earthquake. The aim of the committee is, from viewpoints of risk analysts, to create and relate messages about risk issues in 2-3 years, in ten years and in thirty years from the earthquake. To do this, the committee garners SRA-Japan member's opinions about possible risks in Japan by using Delphi method. In SRA-Japan, there are over 600 members in interdisciplinary fields from various backgrounds, thus the messages are expected to be helpful for Japanese society to lower its risks and to optimize the resource allocation. The research is now underway. An interim report will be presented. (author)

Modelling psychological responses to the Great East Japan earthquake and nuclear incident.

Directory of Open Access Journals (Sweden)

Robin Goodwin

Full Text Available The Great East Japan (Tōhoku/Kanto earthquake of March 2011 was followed by a major tsunami and nuclear incident. Several previous studies have suggested a number of psychological responses to such disasters. However, few previous studies have modelled individual differences in the risk perceptions of major events, or the implications of these perceptions for relevant behaviours. We conducted a survey specifically examining responses to the Great Japan earthquake and nuclear incident, with data collected 11-13 weeks following these events. 844 young respondents completed a questionnaire in three regions of Japan; Miyagi (close to the earthquake and leaking nuclear plants, Tokyo/Chiba (approximately 220 km from the nuclear plants, and Western Japan (Yamaguchi and Nagasaki, some 1000 km from the plants. Results indicated significant regional differences in risk perception, with greater concern over earthquake risks in Tokyo than in Miyagi or Western Japan. Structural equation analyses showed that shared normative concerns about earthquake and nuclear risks, conservation values, lack of trust in governmental advice about the nuclear hazard, and poor personal control over the nuclear incident were positively correlated with perceived earthquake and nuclear risks. These risk perceptions further predicted specific outcomes (e.g. modifying homes, avoiding going outside, contemplating leaving Japan. The strength and significance of these pathways varied by region. Mental health and practical implications of these findings are discussed in the light of the continuing uncertainties in Japan following the March 2011 events.

Modelling psychological responses to the Great East Japan earthquake and nuclear incident.

Science.gov (United States)

Goodwin, Robin; Takahashi, Masahito; Sun, Shaojing; Gaines, Stanley O

2012-01-01

The Great East Japan (Tōhoku/Kanto) earthquake of March 2011 was followed by a major tsunami and nuclear incident. Several previous studies have suggested a number of psychological responses to such disasters. However, few previous studies have modelled individual differences in the risk perceptions of major events, or the implications of these perceptions for relevant behaviours. We conducted a survey specifically examining responses to the Great Japan earthquake and nuclear incident, with data collected 11-13 weeks following these events. 844 young respondents completed a questionnaire in three regions of Japan; Miyagi (close to the earthquake and leaking nuclear plants), Tokyo/Chiba (approximately 220 km from the nuclear plants), and Western Japan (Yamaguchi and Nagasaki, some 1000 km from the plants). Results indicated significant regional differences in risk perception, with greater concern over earthquake risks in Tokyo than in Miyagi or Western Japan. Structural equation analyses showed that shared normative concerns about earthquake and nuclear risks, conservation values, lack of trust in governmental advice about the nuclear hazard, and poor personal control over the nuclear incident were positively correlated with perceived earthquake and nuclear risks. These risk perceptions further predicted specific outcomes (e.g. modifying homes, avoiding going outside, contemplating leaving Japan). The strength and significance of these pathways varied by region. Mental health and practical implications of these findings are discussed in the light of the continuing uncertainties in Japan following the March 2011 events.

Prospect of future housing and risk of psychological distress at 1 year after an earthquake disaster.

Science.gov (United States)

Nakaya, Naoki; Nakamura, Tomohiro; Tsuchiya, Naho; Narita, Akira; Tsuji, Ichiro; Hozawa, Atsushi; Tomita, Hiroaki

2016-04-01

Since the Great East Japan Earthquake in 2011, many of the affected have been forced to live in temporary housing or at a relative's house. Special attention needs to be paid to the negative health impacts resulting from such changes in living conditions. This study examined the association between future housing prospects and the risk of psychological distress 1 year after the earthquake. In 2012, a questionnaire was completed by a cross-sectional study of people aged 20 years or older living in Shichigahama Town, Miyagi, northeastern Japan, an area that had been severely inundated by the tsunami. Future housing prospects post-earthquake were classified into four categories: already settled in permanent housing, moving to new housing, under consideration, or unable to make any plans. Psychological distress was evaluated using the Kessler 6 scale, defined as ≥5 points out of 24. We performed multiple logistic regression analyses adjusted for potential confounding factors. Of the 3614 individuals studied, subjects whose future housing was under consideration (odds ratio [OR] = 2.1, 95% confidence interval [CI] = 1.6-2.7, P prospects were under consideration and those who were unable to make any future housing plans were at a higher risk of psychological distress 1 year after the earthquake disaster. © 2015 The Authors. Psychiatry and Clinical Neurosciences © 2015 Japanese Society of Psychiatry and Neurology.

Social media use and goals after the Great East Japan Earthquake

OpenAIRE

Jung, Joo-Young

2012-01-01

This paper examines the use of social media after the 2011 Great East Japan Earthquake. Based on media system dependency theory, the study focuses on the ways in which people used different types of social media to cope with a highly ambiguous situation created by the earthquake. A survey of Japanese university students revealed that the respondents used different forms of social media with different goals. Moreover, use of a particular social media type influenced the relative importance of ...

Ground Motion Prediction for Great Interplate Earthquakes in Kanto Basin Considering Variation of Source Parameters

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Sekiguchi, H.; Yoshimi, M.; Horikawa, H.

2011-12-01

Broadband ground motions are estimated in the Kanto sedimentary basin which holds Tokyo metropolitan area inside for anticipated great interplate earthquakes along surrounding plate boundaries. Possible scenarios of great earthquakes along Sagami trough are modeled combining characteristic properties of the source area and adequate variation in source parameters in order to evaluate possible ground motion variation due to next Kanto earthquake. South to the rupture area of the 2011 Tohoku earthquake along the Japan trench, we consider possible M8 earthquake. The ground motions are computed with a four-step hybrid technique. We first calculate low-frequency ground motions at the engineering basement. We then calculate higher-frequency ground motions at the same position, and combine the lower- and higher-frequency motions using a matched filter. We finally calculate ground motions at the surface by computing the response of the alluvium-diluvium layers to the combined motions at the engineering basement.

Heterogeneous rupture in the great Cascadia earthquake of 1700 inferred from coastal subsidence estimates

Science.gov (United States)

Wang, Pei-Ling; Engelhart, Simon E.; Wang, Kelin; Hawkes, Andrea D.; Horton, Benjamin P.; Nelson, Alan R.; Witter, Robert C.

2013-01-01

Past earthquake rupture models used to explain paleoseismic estimates of coastal subsidence during the great A.D. 1700 Cascadia earthquake have assumed a uniform slip distribution along the megathrust. Here we infer heterogeneous slip for the Cascadia margin in A.D. 1700 that is analogous to slip distributions during instrumentally recorded great subduction earthquakes worldwide. The assumption of uniform distribution in previous rupture models was due partly to the large uncertainties of then available paleoseismic data used to constrain the models. In this work, we use more precise estimates of subsidence in 1700 from detailed tidal microfossil studies. We develop a 3-D elastic dislocation model that allows the slip to vary both along strike and in the dip direction. Despite uncertainties in the updip and downdip slip extensions, the more precise subsidence estimates are best explained by a model with along-strike slip heterogeneity, with multiple patches of high-moment release separated by areas of low-moment release. For example, in A.D. 1700, there was very little slip near Alsea Bay, Oregon (~44.4°N), an area that coincides with a segment boundary previously suggested on the basis of gravity anomalies. A probable subducting seamount in this area may be responsible for impeding rupture during great earthquakes. Our results highlight the need for more precise, high-quality estimates of subsidence or uplift during prehistoric earthquakes from the coasts of southern British Columbia, northern Washington (north of 47°N), southernmost Oregon, and northern California (south of 43°N), where slip distributions of prehistoric earthquakes are poorly constrained.

Re‐estimated effects of deep episodic slip on the occurrence and probability of great earthquakes in Cascadia

Science.gov (United States)

Beeler, Nicholas M.; Roeloffs, Evelyn A.; McCausland, Wendy

2013-01-01

Mazzotti and Adams (2004) estimated that rapid deep slip during typically two week long episodes beneath northern Washington and southern British Columbia increases the probability of a great Cascadia earthquake by 30–100 times relative to the probability during the ∼58 weeks between slip events. Because the corresponding absolute probability remains very low at ∼0.03% per week, their conclusion is that though it is more likely that a great earthquake will occur during a rapid slip event than during other times, a great earthquake is unlikely to occur during any particular rapid slip event. This previous estimate used a failure model in which great earthquakes initiate instantaneously at a stress threshold. We refine the estimate, assuming a delayed failure model that is based on laboratory‐observed earthquake initiation. Laboratory tests show that failure of intact rock in shear and the onset of rapid slip on pre‐existing faults do not occur at a threshold stress. Instead, slip onset is gradual and shows a damped response to stress and loading rate changes. The characteristic time of failure depends on loading rate and effective normal stress. Using this model, the probability enhancement during the period of rapid slip in Cascadia is negligible (stresses of 10 MPa or more and only increases by 1.5 times for an effective normal stress of 1 MPa. We present arguments that the hypocentral effective normal stress exceeds 1 MPa. In addition, the probability enhancement due to rapid slip extends into the interevent period. With this delayed failure model for effective normal stresses greater than or equal to 50 kPa, it is more likely that a great earthquake will occur between the periods of rapid deep slip than during them. Our conclusion is that great earthquake occurrence is not significantly enhanced by episodic deep slip events.

Report on maternal anxiety 16 months after the great East Japan earthquake disaster: anxiety over radioactivity.

Science.gov (United States)

Yoshii, Hatsumi; Saito, Hidemitsu; Kikuchi, Saya; Ueno, Takashi; Sato, Kineko

2014-06-25

The Great East Japan Earthquake occurred on March 11, 2011. The tsunami caused extensive damage to the Fukushima Daiichi Nuclear Power Plant, resulting in a level 7 nuclear accident. Among those affected by this combined disaster were many pregnant and parturient women. Sixteen months after the earthquake, we conducted a questionnaire survey on anxiety among 259 women who gave birth around the time of the earthquake in Miyagi Prefecture, one of the affected areas. Participants reported 12 categories of anxiety, including anxiety over radioactivity. This study aimed to determine anxiety over radioactivity among this specific population and to record measures for future study. Anxiety over radiation was classified into seven subcategories: food safety, outdoor safety, effects on the fetuses of pregnant women, effects on children, radiation exposure, economic problems, and distrust of information disclosed. This study confirmed that concrete types of anxiety over radiation were keenly felt by mothers who had experienced the disaster who were currently raising children. The findings suggest the need to provide accurate information to these mothers, who are otherwise inundated with miscellaneous confusing information.

Long Period Source Characteristics of Great Earthquakes: diagnosing complexity

Science.gov (United States)

Rivera, L. A.; Kanamori, H.

2013-12-01

With the commonly used centroid moment tensor inversions, just one number represents the long period size of the event, the seismic moment Mo (or corresponding Mw). However, several recent studies have clearly demonstrated that this is not satisfactory, at least for some earthquakes. For example, for the 2004 Sumatra-Andaman Is. Earthquake, the amplitudes of long-period normal modes indicated that the effective seismic moment increases from 4.0x1022 to 7.1x1022 N-m as the period increases from 300 to 1000 sec. For the 2009 Samoa Is. earthquake (Mw=8.1), the moment tensor was found to be strongly dependent on frequency because the source of this earthquake consists of at least 2 distinct events with very different mechanisms. It is possible that other large and great earthquakes may have similar complex characteristics, but with the standard moment tensor inversion with a single frequency band, we may not notice this easily. Here we investigate the possible frequency dependence of the moment tensor of large earthquakes by performing W phase inversions using teleseismic data and equally spaced narrow overlapping frequency bands. We investigate frequencies from 2.6 to 3.8 mHz. We focus on the variation with frequency of the scalar moment, the amount of non double couple and the focal mechanism. We apply this technique to 30 major events in the period 1994-2013 and use the results to detect source complexity. We class them in three groups according to the variability of the source parameters with frequency: Simple, Complex and Intermediate events and we discuss the correlation of the result of this approach with independent observations of source complexity.

Facts about the Eastern Japan Great Earthquake of March 2011

Science.gov (United States)

Moriyama, T.

2011-12-01

The 2011 great earthquake was a magnitude 9.0 Mw undersea megathrust earthquake off the coast of Japan that occurred early morning UTC on Friday, 11 March 2011, with the epicenter approximately 70 kilometres east of the Oshika Peninsula of Tohoku and the hypocenter at an underwater depth of approximately 32 km. It was the most powerful known earthquake to have hit Japan, and one of the five most powerful earthquakes in the world overall since modern record keeping began in 1900. The earthquake triggered extremely destructive tsunami waves of up to 38.9 metres that struck Tohoku Japan, in some cases traveling up to 10 km inland. In addition to loss of life and destruction of infrastructure, the tsunami caused a number of nuclear accidents, primarily the ongoing level 7 meltdowns at three reactors in the Fukushima I Nuclear Power Plant complex, and the associated evacuation zones affecting hundreds of thousands of residents. The Japanese National Police Agency has confirmed 1,5457 deaths, 5,389 injured, and 7,676 people missing across eighteen prefectures, as well as over 125,000 buildings damaged or destroyed. JAXA carried out ALOS emergency observation just after the earthquake occured, and acquired more than 400 scenes over the disaster area. The coseismic interferogram by InSAR analysis cleary showing the epicenter of the earthquake and land surface deformation over Tohoku area. By comparison of before and after satellite images, the large scale damaged area by tunami are extracted. These images and data can access via JAXA website and also GEO Tohoku oki event supersite website.

Multi-Sensors Observations of Pre-Earthquake Signals. What We Learned from the Great Tohoku Earthquake?

Science.gov (United States)

Ouzonounov, D.; Pulinets, S.; Papadopoulos, G.; Kunitsyn, V.; Nesterov, I.; Hattori, K.; Kafatos, M.; Taylor, P.

2012-01-01

The lessons learned from the Great Tohoku EQ (Japan, 2011) will affect our future observations and an analysis is the main focus of this presentation. Multi-sensors observations and multidisciplinary research is presented in our study of the phenomena preceding major earthquakes Our approach is based on a systematic analysis of several physical and environmental parameters, which been reported by others in connections with earthquake processes: thermal infrared radiation; temperature; concentration of electrons in the ionosphere; radon/ion activities; and atmospheric temperature/humidity [Ouzounov et al, 2011]. We used the Lithosphere-Atmosphere-Ionosphere Coupling (LAIC) model, one of several possible paradigms [Pulinets and Ouzounov, 2011] to interpret our observations. We retrospectively analyzed the temporal and spatial variations of three different physical parameters characterizing the state of the atmosphere, ionosphere the ground surface several days before the March 11, 2011 M9 Tohoku earthquake Namely: (i) Outgoing Long wave Radiation (OLR) measured at the top of the atmosphere; (ii) Anomalous variations of ionospheric parameters revealed by multi-sensors observations; and (iii) The change in the foreshock sequence (rate, space and time); Our results show that on March 8th, 2011 a rapid increase of emitted infrared radiation was observed and an anomaly developed near the epicenter with largest value occurring on March 11 at 07.30 LT. The GPS/TEC data indicate an increase and variation in electron density reaching a maximum value on March 8. Starting from this day in the lower ionosphere there was also observed an abnormal TEC variation over the epicenter. From March 3 to 11 a large increase in electron concentration was recorded at all four Japanese ground-based ionosondes, which returned to normal after the main earthquake. We use the Japanese GPS network stations and method of Radio Tomography to study the spatiotemporal structure of ionospheric

Multi-level functionality of social media in the aftermath of the Great East Japan Earthquake.

Science.gov (United States)

Jung, Joo-Young; Moro, Munehito

2014-07-01

This study examines the multi-level functionalities of social media in the aftermath of the Great East Japan Earthquake of 11 March 2011. Based on a conceptual model of multi-level story flows of social media (Jung and Moro, 2012), the study analyses the multiple functionalities that were ascribed to social media by individuals, organisations, and macro-level social systems (government and the mass media) after the earthquake. Based on survey data, a review of Twitter timelines and secondary sources, the authors derive five functionalities of social media: interpersonal communications with others (micro level); channels for local governments; organisations and local media (meso level); channels for mass media (macro level); information sharing and gathering (cross level); and direct channels between micro-/meso- and macro-level agents. The study sheds light on the future potential of social media in disaster situations and suggests how to design an effective communication network to prepare for emergency situations. © 2014 The Author(s). Disasters © Overseas Development Institute, 2014.

Refinements on the inferred causative faults of the great 2012 Indian Ocean earthquakes

Science.gov (United States)

Revathy, P. M.; Rajendran, K.

2014-12-01

As the largest known intra-plate strike-slip events, the pair of 2012 earthquakes in the Wharton Basin is a rarity. Separated in time by 2 hours these events rouse interest also because of their short inter-event duration, complex rupture mechanism, and spatial-temporal proximity to the great 2004 Sumatra plate boundary earthquake. Reactivation of fossil ridge-transform pairs is a favoured mechanism for large oceanic plate earthquakes and their inherent geometry triggers earthquakes on conjugate fault systems, as observed previously in the Wharton Basin. The current debate is whether the ruptures occurred on the WNW-ESE paleo ridges or the NNE-SSW paleo transforms. Back-projection models give a complex rupture pattern that favours the WNW-ESE fault [1]. However, the static stress changes due to the 2004 Sumatra earthquake and 2005 Nias earthquake favour the N15°E fault [2]. We use the Teleseismic Body-Wave Inversion Program [3] and waveform data from Global Seismic Network, to obtain the best fit solutions using P and S-wave synthetic modelling. The preliminary P-wave analysis of both earthquakes gives source parameters that are consistent with the Harvard CMT solutions. The obtained slip distribution complies with the NNE-SSW transforms. Both these earthquakes triggered small tsunamis which appear as two distinctive pulses on 13 Indian Ocean tide gauges and buoys. Frequency spectra of the tsunami recordings from various azimuths provide additional constraint for the choice of the causative faults. References: [1] Yue, H., T. Lay, and K. D. Koper (2012), En echelon and orthogonal fault ruptures of the 11 April 2012 great intraplate earthquakes, Nature, 490, 245-249, doi:10.1038/nature11492 [2] Delescluse, M., N. Chamot-Rooke, R. Cattin, L. Fleitout, O. Trubienko and C. Vigny April 2012 intra-oceanic seismicity off Sumatra boosted by the Banda-Aceh megathrust, Nature, 490(2012), pp. 240-244, doi:10.1038/nature11520 [3] M. Kikuchi and H. Kanamori, Note on

My Road to Transform Faulting 1963; Long-Term Precursors to Recent Great Earthquakes

Science.gov (United States)

Sykes, L. R.

2017-12-01

My road to plate tectonics started serendipitously in 1963 in a remote area of the southeast Pacific when I was studying the propagation of short-period seismic surface waves for my PhD. The earthquakes I used as sources were poorly located. I discovered that my relocated epicenters followed the crest of the East Pacific Rise but then suddenly took a sharp turn to the east at what I interpreted to be a major fracture zone 1000 km long before turning again to the north near 55 degrees south. I noted that earthquakes along that zone only occurred between the two ridge crests, an observation Tuzo Wilson used to develop his hypothesis of transform faulting. Finding a great, unknown fracture zone led me to conclude that work on similar faults that intersect the Mid-Oceanic Ridge System was more important than my study of surface waves. I found similar great faults over the next two years and obtained refined locations of earthquakes along several island arcs. When I was in Fiji and Tonga during 1965 studying deep earthquakes, James Dorman wrote to me about Wilson's paper and I thought about testing his hypothesis. I started work on it the spring of 1966 immediately after I learned about the symmetrical "magic magnetic anomaly profile" across the East Pacific Rise of Pitman and Heirtzler. I quickly obtained earthquake mechanisms that verified the transform hypothesis and its related concepts of seafloor spreading and continental drift. As an undergraduate in the late 1950s, my mentor told me that respectable young earth scientists should not work on vague and false mobilistic concepts like continental drift since continents cannot plow through strong oceanic crust. Hence, until spring 1966, I did not take continental drift seriously. The second part of my presentation involves new evidence from seismology and GPS of what appear to be long-term precursors to a number of great earthquakes of the past decade.

A Preliminary Analysis on the Dynamics of the Ms8.0 Great Wenchuan, Sichuan, China Earthquake

Science.gov (United States)

Zhang, W.

2008-12-01

On May 12, 2008, a huge earthquake with magnitude Ms8.0 occurred in the Wenhuan, Sichuan Province of China. This event was the most devastating earthquake in the mainland of China since the 1976 M7.8 Tangshan earthquake. It resulted in tremendous losses of life and property. So far, there are 69,181 persons killed, and 18,522 still missing. Due to occur in the mountainous area, this great earthquake and the following thousands aftershocks also caused many other geological disasters, such as landslide, mud-rock flow and "quake lakes" which formed by landslide-induced reservoirs. This earthquake occurred along the Longmenshan fault, as the result of motion on a northeast striking reverse fault or thrust fault on the northwestern margin of the Sichuan Basin. The earthquake's epicenter and focal-mechanism are consistent with it having occurred as the result of movement on the Longmenshan fault or a tectonically related fault. The earthquake reflects tectonic stresses resulting from the convergence of crustal material slowly moving from the high Tibetan Plateau, to the west, against strong crust underlying the Sichuan Basin and southeastern China. In this study, the spatial and temporal distribution of the stress on the fault plane of this great earthquake is estimated from the inversion results (Chen Ji, 2008) by solving the elastodynamic equations. Then, the dynamic source parameters are determined and the relations between the shear stress and the slip, the shear stress and the slip-rate for all grid positions on the fault are investigated. Finally, the frictional law for the source rupture is inferred from the dynamic source parameters. Based on the obtained dynamic source parameters, we try to rebuild the dynamic rupture process of this event and discuss the characteristics of this great earthquake.

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

Science.gov (United States)

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

2018-04-01

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

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

Science.gov (United States)

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

2018-03-01

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

The Gibraltar Arc seismogenic zone and the great Lisbon earthquake of 1755

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Gutscher, M.-A.; Malod, J. A.; Rehault, J.-P.; Thiebot, E.; Contrucci, I.; Baptista, M. A.; Miranda, J. M.

2003-04-01

New geophysical data provide compelling evidence for an active east dipping subduction zone beneath the Gibraltar Arc. SISMAR marine seismic data in the Gulf of Cadiz image an actively deforming accretionary wedge, with east dipping thrust faults disrupting the seafloor and soleing out to an east dipping decollement. Tomographic cross-sections as well as hypocenter distribution support a continuous east dipping slab of oceanic lithosphere from the Atlantic domain to beneath the Western Alboran Sea. The great Lisbon earthquake of 1755 (felt as far away as Hamburg, the Azores and Cape Verde Islands) has the largest documented felt area of any shallow earthquake and an estimated magnitude of 8.5 - 9.0. The associated tsunami ravaged the coast of SW Portugal and the Gulf of Cadiz, with run-up heights reported to have reached 5 - 15 m. While several source regions offshore SW Portugal have been proposed (e.g. - Gorringe Bank, Marques de Pombal fault), no single source appears to be able to account for the great seismic moment and the tsunami amplitude and travel-time observations. We propose the Gibraltar arc seismogenic zone to be the source of the 1755 earthquake. This hypothesis may be tested in several ways. We perform tsunami wave form modeling for a shallow east dipping fault plane with dimensions of 180 km (N-S) x 210 km (E-W) and a co-seismic slip of 20 m. For convergence rates of 1 - 2 cm/yr an event of this magnitude could recur every 1000 - 2000 years. Furthermore, the DELILA geophysical cruise is proposed for 2004 to conduct a bathymetric and seismic survey of the accretionary wedge and to sample the turbidites in the adjacent abyssal plains which record the history of great earthquakes.

Measures for groundwater security during and after the Hanshin-Awaji earthquake (1995) and the Great East Japan earthquake (2011), Japan

Science.gov (United States)

Tanaka, Tadashi

2016-03-01

Many big earthquakes have occurred in the tectonic regions of the world, especially in Japan. Earthquakes often cause damage to crucial life services such as water, gas and electricity supply systems and even the sewage system in urban and rural areas. The most severe problem for people affected by earthquakes is access to water for their drinking/cooking and toilet flushing. Securing safe water for daily life in an earthquake emergency requires the establishment of countermeasures, especially in a mega city like Tokyo. This paper described some examples of groundwater use in earthquake emergencies, with reference to reports, books and newspapers published in Japan. The consensus is that groundwater, as a source of water, plays a major role in earthquake emergencies, especially where the accessibility of wells coincides with the emergency need. It is also important to introduce a registration system for citizen-owned and company wells that can form the basis of a cooperative during a disaster; such a registration system was implemented by many Japanese local governments after the Hanshin-Awaji Earthquake in 1995 and the Great East Japan Earthquake in 2011, and is one of the most effective countermeasures for groundwater use in an earthquake emergency. Emphasis is also placed the importance of establishing of a continuous monitoring system of groundwater conditions for both quantity and quality during non-emergency periods.

Future Earth: Reducing Loss By Automating Response to Earthquake Shaking

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Allen, R. M.

2014-12-01

Earthquakes pose a significant threat to society in the U.S. and around the world. The risk is easily forgotten given the infrequent recurrence of major damaging events, yet the likelihood of a major earthquake in California in the next 30 years is greater than 99%. As our societal infrastructure becomes ever more interconnected, the potential impacts of these future events are difficult to predict. Yet, the same inter-connected infrastructure also allows us to rapidly detect earthquakes as they begin, and provide seconds, tens or seconds, or a few minutes warning. A demonstration earthquake early warning system is now operating in California and is being expanded to the west coast (www.ShakeAlert.org). In recent earthquakes in the Los Angeles region, alerts were generated that could have provided warning to the vast majority of Los Angelinos who experienced the shaking. Efforts are underway to build a public system. Smartphone technology will be used not only to issue that alerts, but could also be used to collect data, and improve the warnings. The MyShake project at UC Berkeley is currently testing an app that attempts to turn millions of smartphones into earthquake-detectors. As our development of the technology continues, we can anticipate ever-more automated response to earthquake alerts. Already, the BART system in the San Francisco Bay Area automatically stops trains based on the alerts. In the future, elevators will stop, machinery will pause, hazardous materials will be isolated, and self-driving cars will pull-over to the side of the road. In this presentation we will review the current status of the earthquake early warning system in the US. We will illustrate how smartphones can contribute to the system. Finally, we will review applications of the information to reduce future losses.

Creating a tsunami disaster archive of the Great Northeastern Japan earthquake using images uploaded to the internet

International Nuclear Information System (INIS)

Endo, N; Takehara, A

2014-01-01

We think that the that the experiences from the disaster caused by the Great Northeastern Earthquake in Japan must be of great interest to people not only in the stricken areas but in the whole of Japan and the whole world. Accordingly, we tried to create a method to preserve the digital images of Great Northeastern Earthquake for the next generation. The Creative Commons License may be one of the most useful solutions to avoid complicated processes when a person other than authors would like to build a disaster archive using images uploaded to the Internet

Geological and historical evidence of irregular recurrent earthquakes in Japan.

Science.gov (United States)

Satake, Kenji

2015-10-28

Great (M∼8) earthquakes repeatedly occur along the subduction zones around Japan and cause fault slip of a few to several metres releasing strains accumulated from decades to centuries of plate motions. Assuming a simple 'characteristic earthquake' model that similar earthquakes repeat at regular intervals, probabilities of future earthquake occurrence have been calculated by a government committee. However, recent studies on past earthquakes including geological traces from giant (M∼9) earthquakes indicate a variety of size and recurrence interval of interplate earthquakes. Along the Kuril Trench off Hokkaido, limited historical records indicate that average recurrence interval of great earthquakes is approximately 100 years, but the tsunami deposits show that giant earthquakes occurred at a much longer interval of approximately 400 years. Along the Japan Trench off northern Honshu, recurrence of giant earthquakes similar to the 2011 Tohoku earthquake with an interval of approximately 600 years is inferred from historical records and tsunami deposits. Along the Sagami Trough near Tokyo, two types of Kanto earthquakes with recurrence interval of a few hundred years and a few thousand years had been recognized, but studies show that the recent three Kanto earthquakes had different source extents. Along the Nankai Trough off western Japan, recurrence of great earthquakes with an interval of approximately 100 years has been identified from historical literature, but tsunami deposits indicate that the sizes of the recurrent earthquakes are variable. Such variability makes it difficult to apply a simple 'characteristic earthquake' model for the long-term forecast, and several attempts such as use of geological data for the evaluation of future earthquake probabilities or the estimation of maximum earthquake size in each subduction zone are being conducted by government committees. © 2015 The Author(s).

Reactor experiments, workshops, and human resource development education simulating the Great East Japan Earthquake

International Nuclear Information System (INIS)

Horiguchi, Tetsuo; Yamamoto, Tomosada

2012-01-01

Kinki University Atomic Energy Research Institute has been implementing a social education program such as reactor experiments and training sessions for junior and senior high school teachers since 1987, and in recent years, it has been implementing an education program for common citizens. However, the Great East Japan Earthquake has made it necessary to consider not only the dissemination of accurate knowledge, but also responding to the anxiety on nuclear power. This paper explains the contents of the social contribution activities and workshops conducted at Kinki University Atomic Energy Research Institute, after the Great East Japan Earthquake and the Fukushima Daiichi Nuclear Power Station accident. As the activities that are carried out in addition to training sessions, it introduces the implementation state of telephone consultation about nuclear power, and earthquake reconstruction assistance advisory at Kawamata Town, Date-gun, Fukushima Prefecture. As workshop support, it reports human resource development education in the nuclear field at the university, activities at the workshops for junior/senior high school teachers and general public, and questionnaire survey at the time of the workshops. (A.O.)

Symptoms of Post-Traumatic Stress Disorder Among Young Children 2 Years After the Great East Japan Earthquake.

Science.gov (United States)

Fujiwara, Takeo; Yagi, Junko; Homma, Hiroaki; Mashiko, Hirofumi; Nagao, Keizo; Okuyama, Makiko

2017-04-01

The aim of this study was to investigate the prevalence of post-traumatic stress disorder (PTSD) and its association with each traumatic experience among 5- to 8-year-old children 2 years after the Great East Japan Earthquake. Children ages 5-8 years who were in selected preschool classes on March 11, 2011, in 3 prefectures affected by the earthquake and 1 prefecture that was unaffected, participated in the study (N=280). PTSD symptoms were assessed through questionnaires completed by caregivers and interviews by psychiatrists or psychologists conducted between September 2012 and May 2013 (ie, 1.5-2 years after the earthquake). Among children who experienced the earthquake, 33.8% exhibited PTSD symptoms. Of the different traumatic experiences, experiencing the earthquake and the loss of distant relatives or friends were independently associated with PTSD symptoms; prevalence ratios: 6.88 (95% confidence interval [CI]: 2.06-23.0) and 2.48 (95% CI: 1.21-5.08), respectively. Approximately 1 in 3 young children in the affected communities exhibited PTSD symptoms, even 2 years after the Great East Japan Earthquake. These data may be useful for preventing PTSD symptoms after natural disasters and suggest the importance of providing appropriate mental health services for children. (Disaster Med Public Health Preparedness. 2017;11:207-215).

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

Science.gov (United States)

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

2005-12-01

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

The earthquake problem in engineering design: generating earthquake design basis information

International Nuclear Information System (INIS)

Sharma, R.D.

1987-01-01

Designing earthquake resistant structures requires certain design inputs specific to the seismotectonic status of the region, in which a critical facility is to be located. Generating these inputs requires collection of earthquake related information using present day techniques in seismology and geology, and processing the collected information to integrate it to arrive at a consolidated picture of the seismotectonics of the region. The earthquake problem in engineering design has been outlined in the context of a seismic design of nuclear power plants vis a vis current state of the art techniques. The extent to which the accepted procedures of assessing seismic risk in the region and generating the design inputs have been adherred to determine to a great extent the safety of the structures against future earthquakes. The document is a step towards developing an aproach for generating these inputs, which form the earthquake design basis. (author)

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

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A. Muhammad

2017-12-01

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

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.

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

History of decontamination after the Great East Japan Earthquake

International Nuclear Information System (INIS)

Omura, Takashi; Onodera, Hideaki; Morishita, Satoru; Kato, Sei

2015-01-01

The magnitude 9.0 earthquake (the Great East Japan Earthquake) hit Japan on March 11, 2011 brought tsunami hazard as well as a nuclear accident in addition to the seismic hazard. A wide area of the eastern Japan was contaminated by radioactive materials released from the Fukushima Daiichi Nuclear Power Plant of the Tokyo Electric Power Company. In response to the unprecedented situation of the radioactive pollution after the accident, the Act on Special Measures Concerning the Handling of Radioactive Pollution was enacted in August 2011. The Ministry of the Environment (MOE) has formulated a set of guidelines by the end of 2011 to provide information on how to store and manage contaminated waste. In addition, the MOE established 'The Policies for the Decontamination of Specific Areas (Decontamination Roadmap)' in January 2012. As a result, the radiation dose rate has decreased by approximately 46% in the residential area of Naraha town. The MOE will have been promoting decontamination and construction of interim storage facilities which are able to store and manage the removed soils and incineration ashes generated from decontamination works. (author)

Lessons Learned from Data Management Activities after the Great East Japan Earthquake in March 2011

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A Kitamoto

2013-02-01

Full Text Available This paper summarizes our effort towards managing the multi-disciplinary disaster-related data from the Great East Japan Earthquake, which happened on March 11, 2011 off the coast of Northeast Japan. This earthquake caused the largest tsunami in the recorded history of Japan, killed many people along the coast, and caused a nuclear disaster in Fukushima, which continues to affect a large area of Japan. Just after the earthquake, we started crisis response data management activities to provide useful information for supporting disaster response and recovery. This paper introduces the various types of datasets we made from the viewpoint of data management processing and draws lessons from our post-disaster activities.

Towards the Future "Earthquake" School in the Cloud: Near-real Time Earthquake Games Competition in Taiwan

Science.gov (United States)

Chen, K. H.; Liang, W. T.; Wu, Y. F.; Yen, E.

2014-12-01

To prevent the future threats of natural disaster, it is important to understand how the disaster happened, why lives were lost, and what lessons have been learned. By that, the attitude of society toward natural disaster can be transformed from training to learning. The citizen-seismologists-in-Taiwan project is designed to elevate the quality of earthquake science education by means of incorporating earthquake/tsunami stories and near-real time earthquake games competition into the traditional curricula in schools. Through pilot of courses and professional development workshops, we have worked closely with teachers from elementary, junior high, and senior high schools, to design workable teaching plans through a practical operation of seismic monitoring at home or school. We will introduce how the 9-years-old do P- and S-wave picking and measure seismic intensity through interactive learning platform, how do scientists and school teachers work together, and how do we create an environment to facilitate continuous learning (i.e., near-real time earthquake games competition), to make earthquake science fun.

Anomalies of total column CO and O3 associated with great earthquakes in recent years

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Y. Cui

2013-10-01

Full Text Available Variations of total column CO and O3 in the atmosphere over the epicenter areas of 35 great earthquakes that occurred throughout the world in recent years were studied based on the hyper-spectrum data from Atmospheric Infrared Sounder (AIRS. It was found that anomalous increases of CO and/or O3 concentrations occurred over the epicenter areas of 12 earthquakes among the 35 studied ones. However, increases in both CO and O3 concentrations were found for 6 earthquakes. The O3 anomalies appeared in the month when the earthquake occurred and lasted for a few months, whereas CO anomalies occurred irregularly. The duration of CO and O3 anomalies related to the earthquakes ranged from 1 to 6 months. The anomalies of CO concentration related to the earthquake can be mainly attributed to gas emission from the lithosphere and photochemical reaction, while the anomalous increases in O3 concentration can be mainly due to the transport of O3-enriched air and photochemical reaction. However, more work needs to be done in order to understand the mechanism of the CO and O3 anomalies further.

Outline of geophysical investigations on the great earthquake in the south-west Japan on Dec. 21, 1946

Science.gov (United States)

Nagata, Takeshi

1947-01-01

In in the early morning of Dec. 21, 1946, a great destructive earthquake occurred in southern-western Japan. According to the seismogram obtained in our university, the earthquake motion began at Tokyo from 4 h 20 m 10.4 s on Dec. 21, 1946. The maximum amplitude of NS, EW, and up-down components of the earthquake motion at Tokyo was 12.0 mm, 14.0 mm and 3.0 mm respectively, while the initial motion was composed of 80 μ south, 67 μ west and 20 μ down movements.

Kinds of damage that could result from a great earthquake in the central United States

Science.gov (United States)

Hooper, M.G.; Algermissen, S.T.

1985-01-01

In the winter of 1811-12 a series of three great earthquakes occurred in the New Madrid, Missouri seismic zone in the central United States. In addition to the three principal shocks, at least 15 other earthquakes of intensity VIII or more occurred within a year of the first large earthquake on December 16, 1811. The three main shocks were felt over the entire eastern United States. They were strong enough to cause minor damage cause minor damage as far away as Indiana and Ohio on the north, the Carolinas on the east, and southern Mississippi to the south. They were strong enough to cause severe or structural damage in parts of Missouri, Illinois, Indiana, Kentucky, Tennessee, Mississippi, and Arkansas. A later section in this article describes what happened in the epicentral region. Fortunately, few people lived in the severely shaken area in 1811; that is not the case today. What would happen if a series of earthquakes as large and numerous as the "New Madrid" earthquakes were to occur in the New Madrid seismic zone today?

The link between great earthquakes and the subduction of oceanic fracture zones

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R. D. Müller

2012-12-01

Full Text Available Giant subduction earthquakes are known to occur in areas not previously identified as prone to high seismic risk. This highlights the need to better identify subduction zone segments potentially dominated by relatively long (up to 1000 yr and more recurrence times of giant earthquakes. We construct a model for the geometry of subduction coupling zones and combine it with global geophysical data sets to demonstrate that the occurrence of great (magnitude ≥ 8 subduction earthquakes is strongly biased towards regions associated with intersections of oceanic fracture zones and subduction zones. We use a computational recommendation technology, a type of information filtering system technique widely used in searching, sorting, classifying, and filtering very large, statistically skewed data sets on the Internet, to demonstrate a robust association and rule out a random effect. Fracture zone–subduction zone intersection regions, representing only 25% of the global subduction coupling zone, are linked with 13 of the 15 largest (magnitude M_w ≥ 8.6 and half of the 50 largest (magnitude M_w ≥ 8.4 earthquakes. In contrast, subducting volcanic ridges and chains are only biased towards smaller earthquakes (magnitude < 8. The associations captured by our statistical analysis can be conceptually related to physical differences between subducting fracture zones and volcanic chains/ridges. Fracture zones are characterised by laterally continuous, uplifted ridges that represent normal ocean crust with a high degree of structural integrity, causing strong, persistent coupling in the subduction interface. Smaller volcanic ridges and chains have a relatively fragile heterogeneous internal structure and are separated from the underlying ocean crust by a detachment interface, resulting in weak coupling and relatively small earthquakes, providing a conceptual basis for the observed dichotomy.

The Great Maule earthquake: seismicity prior to and after the main shock from amphibious seismic networks

Science.gov (United States)

Lieser, K.; Arroyo, I. G.; Grevemeyer, I.; Flueh, E. R.; Lange, D.; Tilmann, F. J.

2013-12-01

the Great Maule earthquake the Collaborative Research Center SFB 574 'Volatiles and Fluids in Subduction Zones' shot several wide-angle profiles and operated a network, also consisting of OBS and land stations for six months in 2008. Both projects provide a great opportunity to study the evolution of a subduction zone within the seismic cycle of a great earthquake. The most profound features are (i) a sharp reduction in intraslab seismic activity after the Maule earthquake and (ii) a sharp increase in seismic activity at the slab interface above 50 km depth, where large parts of the rupture zone were largely aseismic prior to the Maule earthquake. Further, the aftershock seismicity shows a broader depth distribution above 50 km depth.

Forecasting of future earthquakes in the northeast region of India considering energy released concept

Science.gov (United States)

Zarola, Amit; Sil, Arjun

2018-04-01

This study presents the forecasting of time and magnitude size of the next earthquake in the northeast India, using four probability distribution models (Gamma, Lognormal, Weibull and Log-logistic) considering updated earthquake catalog of magnitude Mw ≥ 6.0 that occurred from year 1737-2015 in the study area. On the basis of past seismicity of the region, two types of conditional probabilities have been estimated using their best fit model and respective model parameters. The first conditional probability is the probability of seismic energy (e × 1020 ergs), which is expected to release in the future earthquake, exceeding a certain level of seismic energy (E × 1020 ergs). And the second conditional probability is the probability of seismic energy (a × 1020 ergs/year), which is expected to release per year, exceeding a certain level of seismic energy per year (A × 1020 ergs/year). The logarithm likelihood functions (ln L) were also estimated for all four probability distribution models. A higher value of ln L suggests a better model and a lower value shows a worse model. The time of the future earthquake is forecasted by dividing the total seismic energy expected to release in the future earthquake with the total seismic energy expected to release per year. The epicentre of recently occurred 4 January 2016 Manipur earthquake (M 6.7), 13 April 2016 Myanmar earthquake (M 6.9) and the 24 August 2016 Myanmar earthquake (M 6.8) are located in zone Z.12, zone Z.16 and zone Z.15, respectively and that are the identified seismic source zones in the study area which show that the proposed techniques and models yield good forecasting accuracy.

2017 Valparaíso earthquake sequence and the megathrust patchwork of central Chile

NARCIS (Netherlands)

Nealy, Jennifer L.; Herman, Matthew W.; Moore, Ginevra L.; Hayes, Gavin P.; Benz, Harley M.; Bergman, Eric A.; Barrientos, Sergio E.

2017-01-01

In April 2017, a sequence of earthquakes offshore Valparaíso, Chile, raised concerns of a potential megathrust earthquake in the near future. The largest event in the 2017 sequence was a M6.9 on 24 April, seemingly colocated with the last great-sized earthquake in the region—a M8.0 in March 1985.

The Great Tangshan Earthquake of 1976

OpenAIRE

Huixian, Liu; Housner, George W.; Lili, Xie; Duxin, He

2002-01-01

At 4:00 a.m. on July 28, 1976 the city of Tangshan, China ceased to exist. A magnitude 7.8 earthquake was generated by a fault that passed through the city and caused 85% of the buildings to collapse or to be so seriously damaged as to be unusable, and the death toll was enormous. The earthquake caused the failures of the electric power system, the water supply system, the sewer system, the telephone and telegraph systems, and radio communications; and the large coal mines and the industries ...

Suicide risk among young children after the Great East Japan Earthquake: A follow-up study.

Science.gov (United States)

Fujiwara, Takeo; Yagi, Junko; Homma, Hiroaki; Mashiko, Hirobumi; Nagao, Keizo; Okuyama, Makiko

2017-07-01

On 11 March 2011, the Great East Japan Earthquake and subsequent tsunami hit East Japan. We aim to investigate the impact of trauma experiences related to the earthquake on suicide risk among young children, stratified by child sex. Participants at baseline were children who were exposed to the 2011 disaster at preschool age (affected area, n=198; unaffected area, n=82, total n=280). From July 2013 to May 2014, suicide risk was assessed using the Mini International Neuropsychiatric Interview for Children and Adolescents (MINI-KID) in a follow-up interview conducted by a child psychiatrist or psychologist (N=210, follow-up rate: 75%). Among young girls in the affected area, 12 out of 65 (18.5%) showed suicidal ideation, which is significantly higher than girls in the unaffected area (4.7%, p for chi-square=0.036). In the multivariate model adjusted for potential confounders and mediators, the odds ratio for 4 or more trauma experiences related to the earthquake was 5.74 (95% confidence interval: 0.83-39.6, p=0.076) compared to no trauma experience related to the earthquake. Among young boys, trauma exposure was not associated with suicidal ideation. Our findings showed that young girls who experienced earthquake-related trauma at preschool age had a higher suicidal ideation 3 years after the earthquake. Copyright © 2017. Published by Elsevier B.V.

COMPARING SEA LEVEL RESPONSE AT MONTEREY, CALIFORNIA FROM THE 1989 LOMA PRIETA EARTHQUAKE AND THE 1964 GREAT ALASKAN EARTHQUAKE

Directory of Open Access Journals (Sweden)

L. C. Breaker

2009-01-01

Full Text Available Two of the largest earthquakes to affect water levels in Monterey Bay in recent years were the Loma Prieta Earthquake (LPE of 1989 with a moment magnitude of 6.9, and the Great Alaskan Earthquake (GAE of 1964 with a moment magnitude of 9.2. In this study, we compare the sea level response of these events with a primary focus on their frequency content and how the bay affected it, itself. Singular Spectrum Analysis (SSA was employed to extract the primary frequencies associated with each event. It is not clear how or exactly where the tsunami associated with the LPE was generated, but it occurred inside the bay and most likely began to take on the characteristics of a seiche by the time it reached the tide gauge in Monterey Harbor. Results of the SSA decomposition revealed two primary periods of oscillation, 9-10 minutes, and 31-32 minutes. The first oscillation is in agreement with the range of periods for the expected natural oscillations of Monterey Harbor, and the second oscillation is consistent with a bay-wide oscillation or seiche mode. SSA decomposition of the GAE revealed several sequences of oscillations all with a period of approximately 37 minutes, which corresponds to the predicted, and previously observed, transverse mode of oscillation for Monterey Bay. In this case, it appears that this tsunami produced quarter-wave resonance within the bay consistent with its seiche-like response. Overall, the sea level responses to the LPE and GAE differed greatly, not only because of the large difference in their magnitudes but also because the driving force in one case occurred inside the bay (LPE, and in the second, outside the bay (GAE. As a result, different modes of oscillation were excited.

[Trust in organizations concerned with risks of the Great East Japan Earthquake].

Science.gov (United States)

Nakayachi, Kazuya; Kudo, Daisuke; Ozaki, Taku

2014-06-01

This study investigated the levels of public trust in organizations associated with the Great East Japan Earthquake. In Study 1 (N = 639), the levels of trust in eight organizations as well as the determinants of trust--perceived salient value similarity (SVS), ability, and motivation--were measured twice, first immediately after the earthquake and then a year later. The results indicated that the trust levels for six of the eight organizations had been preserved, supporting the double asymmetric effect of trust. The results of structural equation modeling (SEM) revealed that SVS explained trust more when the organization had been less trusted. Trust in the organization explains well the perceived reduction of the target risk. The results of SEM in Study 2 (N = 1,030) replicated those of Study 1, suggesting the stability of the explanatory power of the determinants of trust. Implications of the study for risk management practices are discussed.

Urgent Safety Measures in Japan after Great East Japan Earthquake

International Nuclear Information System (INIS)

Taniura, W.; Otani, H.

2012-01-01

Due to tsunami triggered by the Great East Japan Earthquake on March 11, 2011, the operating and refueling reactor facilities at Fukushima Dai-ichi and Dai-ni Nuclear Power Plants of Tokyo Electric Power Co. caused a nuclear hazard. Japanese electric power companies voluntarily began to compile various urgent measures against tsunami within the week the hazard was caused. As for the urgent safety measures of each licensee, it is clarified that effective measures have been appropriately implemented as a result of the inspection of the national government, the verification based on the guideline of the Japan Society of Maintenology and the stress test. (author)

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

A 30-year history of earthquake crisis communication in California and lessons for the future

Science.gov (United States)

Jones, L.

2015-12-01

The first statement from the US Geological Survey to the California Office of Emergency Services quantifying the probability of a possible future earthquake was made in October 1985 about the probability (approximately 5%) that a M4.7 earthquake located directly beneath the Coronado Bay Bridge in San Diego would be a foreshock to a larger earthquake. In the next 30 years, publication of aftershock advisories have become routine and formal statements about the probability of a larger event have been developed in collaboration with the California Earthquake Prediction Evaluation Council (CEPEC) and sent to CalOES more than a dozen times. Most of these were subsequently released to the public. These communications have spanned a variety of approaches, with and without quantification of the probabilities, and using different ways to express the spatial extent and the magnitude distribution of possible future events. The USGS is re-examining its approach to aftershock probability statements and to operational earthquake forecasting with the goal of creating pre-vetted automated statements that can be released quickly after significant earthquakes. All of the previous formal advisories were written during the earthquake crisis. The time to create and release a statement became shorter with experience from the first public advisory (to the 1988 Lake Elsman earthquake) that was released 18 hours after the triggering event, but was never completed in less than 2 hours. As was done for the Parkfield experiment, the process will be reviewed by CEPEC and NEPEC (National Earthquake Prediction Evaluation Council) so the statements can be sent to the public automatically. This talk will review the advisories, the variations in wording and the public response and compare this with social science research about successful crisis communication, to create recommendations for future advisories

Aftershocks and triggered events of the Great 1906 California earthquake

Science.gov (United States)

Meltzner, A.J.; Wald, D.J.

2003-01-01

The San Andreas fault is the longest fault in California and one of the longest strike-slip faults in the world, yet little is known about the aftershocks following the most recent great event on the San Andreas, the Mw 7.8 San Francisco earthquake on 18 April 1906. We conducted a study to locate and to estimate magnitudes for the largest aftershocks and triggered events of this earthquake. We examined existing catalogs and historical documents for the period April 1906 to December 1907, compiling data on the first 20 months of the aftershock sequence. We grouped felt reports temporally and assigned modified Mercalli intensities for the larger events based on the descriptions judged to be the most reliable. For onshore and near-shore events, a grid-search algorithm (derived from empirical analysis of modern earthquakes) was used to find the epicentral location and magnitude most consistent with the assigned intensities. For one event identified as far offshore, the event's intensity distribution was compared with those of modern events, in order to contrain the event's location and magnitude. The largest aftershock within the study period, an M ???6.7 event, occurred ???100 km west of Eureka on 23 April 1906. Although not within our study period, another M ???6.7 aftershock occurred near Cape Mendocino on 28 October 1909. Other significant aftershocks included an M ???5.6 event near San Juan Bautista on 17 May 1906 and an M ???6.3 event near Shelter Cove on 11 August 1907. An M ???4.9 aftershock occurred on the creeping segment of the San Andreas fault (southeast of the mainshock rupture) on 6 July 1906. The 1906 San Francisco earthquake also triggered events in southern California (including separate events in or near the Imperial Valley, the Pomona Valley, and Santa Monica Bay), in western Nevada, in southern central Oregon, and in western Arizona, all within 2 days of the mainshock. Of these trigerred events, the largest were an M ???6.1 earthquake near Brawley

Types of damage that could result from a great earthquake in the New Madrid, Missouri, seismic zone

Science.gov (United States)

Hopper, M.G.; Algermissen, S.T.

1984-01-01

In the winter of 1811–1812 a series of three great earthquakes occurred in the New Madrid seismic zone. In addition to the three principal shocks, at least 15 other earthquakes, Io ≥ VIII, occurred within a year of the first large earthquake on December 16, 1811. The three main shocks were felt over the entire eastern United States. They were strong enough to cause minor damage as far away as Indiana and Ohio on the north, the Carolinas on the east, and southern Mississippi on the south. They were strong enough to cause severe or structural damage in parts of Missouri, Illinois, Indiana, Kentucky, Tennessee, Mississippi, and Arkansas. The section of this poster titled "Seismic history of the New Madrid region" describes what happened in the epicentral region. Fortunately, few people lived in the severely shaken area in 1811; that is not the case today. What would happen if a series of earthquakes as large and numerous as the "New Madrid" earthquakes were to occur in the New Madrid seismic zone today?

Fluctuation patterns of groundwater levels in Tokyo caused by the Great East Japan Earthquake

Science.gov (United States)

Kawamura, Akira; Ishihara, Shigeyuki; Amaguchi, Hideo; Takasaki, Tadakatsu

2016-04-01

The hourly groundwater levels have been observed at 42 sites in Tokyo Metropolis since 1952. The Great East Japan Earthquake occurred at 14:46 JST on March 11, 2011. It was the strongest earthquake on record with a magnitude of 9.0 (Mw) and large fluctuations of unconfined and confined groundwater levels were observed at 102 observation wells in Tokyo, around 400 km away from the epicenter. Abrupt rises and sharp drawdowns of groundwater levels were observed right after the earthquake for most of the wells, although some did not show a change. In this study, taking full advantage of the unique rare case data from the dense groundwater monitoring network in Tokyo, we investigate the fluctuation patterns of unconfined and confined groundwater levels caused by the Great East Japan Earthquake. The groundwater level data used in this study consist of one month time series in March 2011 with one-hour interval. The fluctuation patterns of groundwater levels caused by the earthquake were identified using Self-Organizing Maps (SOM). The SOM, developed by Kohonen, can project high-dimensional, complex target data onto a two-dimensional regularly arranged map in proportion to the degree of properties. In general, the objective of the SOM application is to obtain useful and informative reference vectors. These vectors can be acquired after iterative updates through the training of the SOM. Design of the SOM structure, selection of a proper initialization method, and data transformation methods were carried out in the SOM application process. The reference vectors obtained from the SOM application were fine-tuned using cluster analysis methods. The optimal number of clusters was selected by the Davies-Bouldin index (DBI) using the k-means algorithm. Using the optimal number of cluster, a final fine-tuning cluster analysis was carried out by Ward's method. As a result, the fluctuation patterns of the confined and unconfined groundwater level were classified into eight clusters

Public opinion on environmental and energy issues. Result of the census after 3 years of the Great East Japan Earthquake

International Nuclear Information System (INIS)

Kosugi, Motoko

2014-01-01

The public opinion on the energy and environmental issues has changed greatly in Japan through experiences in and along the Great East Japan Earthquake. We conducted a social survey in order to grasp public opinions for environment and energy issues in March, 2014, which obtained 2313 valid responses (response rate was 64.3%). For the energy and environmental issues, while respondents show high interests in matters related to the Fukushima accident and nuclear power generation as well as electricity prices, they show relatively low interest in every other aspect. With regard to Japan's energy policy in the future, as expectations for renewable and natural sources of energy are large, about 60% of respondents have negative attitude in restart of nuclear power. For nuclear power, as compared to the previous survey conducted in August 2008, evaluation of 'control-ability of environmental impacts' and 'the power companies' risk management ability' was greatly reduced in particular. These results suggest the importance of provoke interest in the energy issues in general, as a premise to seek an understanding of the activities of the government and power companies. Furthermore, in order for the power companies to restore trust from the public, it is important to sympathize to public's anticipations of impacts on the health and environment through uses of nuclear power in the future. (author)

INVESTIGATIVE RESEARCH PROJECTS RELATED TO THE TOHOKU EARTHQUAKE (THE GREAT EAST JAPAN EARTHQUAKE) CONDUCTED IN FUKUSHIMA.

Science.gov (United States)

Yamamoto, Toshiyuki; Hashimoto, Yasuhiro; Yoshida, Masayuki; Ohno, Kikuo; Ohto, Hitoshi; Abe, Masafumi

2015-01-01

On March 11(th) 2011, the Tohoku region of Japan was struck by catastrophic disasters. Thousands of people were killed due to a magnitude 9.0 earthquake and its subsequent tsunami. Furthermore, a serious nuclear crisis occurred in Fukushima Prefecture as a result of the disasters, and an emergency evacuation was ordered to people living near the nuclear power plants. There was a lot of anxiety regarding lost families as well as the influences of radioactivity on the health of people and their children. Based on these urgent and uncertain situations, a number of research projects were developed at many institutes both inside and outside Fukushima. We herein report the investigative research projects related to the Tohoku Earthquake (The Great East Japan Earthquake) conducted after the disasters. The research projects were reviewed by the Institutional Review Board in Fukushima Medical University during the two years following the disasters. The research projects conducted in universities other than Fukushima Medical University were also examined using questionnaire analysis. Among the research projects conducted in Fukushima Medical University (n=424), 7% (n=32) were disaster-related investigative research. The mean duration planned to pursue the projects was 25.5 months. Among these projects, those focusing on the health of Fukushima citizens were most common (n=9), followed by the influence of chronic exposure of radiation on chronic inflammatory disorders (n=6), and the mental health of Fukushima citizens (n=5). They were carefully reviewed for the purpose, suitability, and necessity from ethical as well as scientific viewpoints. The majority of the research projects focused on the effects of the Tohoku Earthquake and/or chronic exposure to low-dose radioactivity on the health of children and pregnant women, as well as on various disorders, such as mental health and chronic inflammatory diseases. On the other hand, among 58 projects we collected from 22

Geodetic Finite-Fault-based Earthquake Early Warning Performance for Great Earthquakes Worldwide

Science.gov (United States)

Ruhl, C. J.; Melgar, D.; Grapenthin, R.; Allen, R. M.

2017-12-01

GNSS-based earthquake early warning (EEW) algorithms estimate fault-finiteness and unsaturated moment magnitude for the largest, most damaging earthquakes. Because large events are infrequent, algorithms are not regularly exercised and insufficiently tested on few available datasets. The Geodetic Alarm System (G-larmS) is a GNSS-based finite-fault algorithm developed as part of the ShakeAlert EEW system in the western US. Performance evaluations using synthetic earthquakes offshore Cascadia showed that G-larmS satisfactorily recovers magnitude and fault length, providing useful alerts 30-40 s after origin time and timely warnings of ground motion for onshore urban areas. An end-to-end test of the ShakeAlert system demonstrated the need for GNSS data to accurately estimate ground motions in real-time. We replay real data from several subduction-zone earthquakes worldwide to demonstrate the value of GNSS-based EEW for the largest, most damaging events. We compare predicted ground acceleration (PGA) from first-alert-solutions with those recorded in major urban areas. In addition, where applicable, we compare observed tsunami heights to those predicted from the G-larmS solutions. We show that finite-fault inversion based on GNSS-data is essential to achieving the goals of EEW.

Prevalence of insomnia among residents of Tokyo and osaka after the great East Japan earthquake: a prospective study.

Science.gov (United States)

Sugiura, Hiroaki; Akahane, Manabu; Ohkusa, Yasushi; Okabe, Nobuhiko; Sano, Tomomi; Jojima, Noriko; Bando, Harumi; Imamura, Tomoaki

2013-01-18

The Great East Japan Earthquake occurred on March 11, 2011. Tokyo and Osaka, which are located 375 km and 750 km, respectively, from the epicenter, experienced tremors of 5.0 lower and 3.0 seismic intensity on the Japan Meteorological Agency scale. The Great East Japan Earthquake was the fourth largest earthquake in the world and was accompanied by a radioactive leak at a nuclear power plant and a tsunami. In the aftermath of a disaster, some affected individuals presented to mental health facilities with acute stress disorder (ASD) and/or post-traumatic stress disorder (PTSD). However, few studies have addressed mental stress problems other than ASD or PTSD among the general public immediately after a disaster. Further, the effects of such a disaster on residents living at considerable distances from the most severely affected area have not been examined. This study aimed to prospectively analyze the effect of a major earthquake on the prevalence of insomnia among residents of Tokyo and Osaka. A prospective online questionnaire study was conducted in Tokyo and Osaka from January 20 to April 30, 2011. An Internet-based questionnaire, intended to be completed daily for a period of 101 days, was used to collect the data. All of the study participants lived in Tokyo or Osaka and were Consumers' Co-operative Union (CO-OP) members who used an Internet-based food-ordering system. The presence or absence of insomnia was determined before and after the earthquake. These data were compared after stratification for the region and participants' age. Multivariate analyses were conducted using logistic regression and a generalized estimating equation. This study was conducted with the assistance of the Japanese CO-OP. The prevalence of insomnia among adults and minors in Tokyo and adults in Osaka increased significantly after the earthquake. No such increase was observed among minors in Osaka. The overall adjusted odds ratios for the risk of insomnia post-earthquake versus pre-earthquake

Coulomb Failure Stress Accumulation in Nepal After the 2015 Mw 7.8 Gorkha Earthquake: Testing Earthquake Triggering Hypothesis and Evaluating Seismic Hazards

Science.gov (United States)

Xiong, N.; Niu, F.

2017-12-01

A Mw 7.8 earthquake struck Gorkha, Nepal, on April 5, 2015, resulting in more than 8000 deaths and 3.5 million homeless. The earthquake initiated 70km west of Kathmandu and propagated eastward, rupturing an area of approximately 150km by 60km in size. However, the earthquake failed to fully rupture the locked fault beneath the Himalaya, suggesting that the region south of Kathmandu and west of the current rupture are still locked and a much more powerful earthquake might occur in future. Therefore, the seismic hazard of the unruptured region is of great concern. In this study, we investigated the Coulomb failure stress (CFS) accumulation on the unruptured fault transferred by the Gorkha earthquake and some nearby historical great earthquakes. First, we calculated the co-seismic CFS changes of the Gorkha earthquake on the nodal planes of 16 large aftershocks to quantitatively examine whether they were brought closer to failure by the mainshock. It is shown that at least 12 of the 16 aftershocks were encouraged by an increase of CFS of 0.1-3 MPa. The correspondence between the distribution of off-fault aftershocks and the increased CFS pattern also validates the applicability of the earthquake triggering hypothesis in the thrust regime of Nepal. With the validation as confidence, we calculated the co-seismic CFS change on the locked region imparted by the Gorkha earthquake and historical great earthquakes. A newly proposed ramp-flat-ramp-flat fault geometry model was employed, and the source parameters of historical earthquakes were computed with the empirical scaling relationship. A broad region south of the Kathmandu and west of the current rupture were shown to be positively stressed with CFS change roughly ranging between 0.01 and 0.5 MPa. The maximum of CFS increase (>1MPa) was found in the updip segment south of the current rupture, implying a high seismic hazard. Since the locked region may be additionally stressed by the post-seismic relaxation of the lower

Factors Associated With Worsened or Improved Mental Health in the Great East Japan Earthquake Survivors.

Science.gov (United States)

Yamanouchi, Tomoko; Hiroshima, Mayo; Takeuchi, Yumiko; Sawada, Yumiko; Takahashi, Makiko; Amagai, Manami

2018-02-01

The aim of this study was to identify factors contributing to the worsening or improved mental health of long-term evacuees over three years following the Great East Japan Earthquake. The Japanese version of the K6 questionnaire was used as a measure of mental health. The first- and third-year survey results were compared and differences in mental health status calculated. Respondents were then divided into two groups according to worsening or improved mental health status. Differences in stress factors, stress relief methods, and demographics were compared between the two groups. Factors associated with exacerbation of poor mental health were the stress factors "Uncertainty about future" (p=0.048) and "Loss of purpose in life" (p=0.023). Multivariable analysis identified two factors associated with improved mental health, the stress relief methods "Accepting myself" (odds ratio (OR): 2.15, 95% confidence interval (CI): 1.02-4.51) and "Interactions with others" (OR: 3.34, 95% CI: 1.43-7.79). While motivation and hope of livelihood reconstruction have gradually risen in the three years since the disaster, anxieties about an uncertain future, loss of purpose in life, and disruption of social networks continue adversely to affect the mental health of survivors. Copyright © 2017 Elsevier Inc. All rights reserved.

Seismogenic Tectonic Environment of 1976 Great Tangshan Earthquake: Results from Dense Seismic Array Observations

Science.gov (United States)

LIU, Qiyuan; WANG, Jun; CHEN, Jiuhui; LI, Shuncheng; GUO, Biao

On July 28, 1976, the great Tangshan earthquake that shook the whole world took place in the Tangshan area of the Hebei Province, China. A big incomprehensible question is why such a tremendous earthquake took place in the Paleo-craton area in North China? It would be worth considering whether a similar event will reoccur in the Tangshan region. In this study, using the receiver function inversion technique and teleseismic P waveform data recorded at the Capital Circle Seismic network and our movable seismic array, we investigated the 3-D S-wave velocity structure of the crust and upper mantle down to 60 km beneath Tangshan area. Our results manifest that (1) the media beneath the Tangshan block cut by active faults are very different from the adjacent area, and all of the active faults surrounding the Tangshan block was through the whole crust; (2) in the upper and middle crust, there exist obvious heterogeneous low-velocity media beneath the Tangshan earthquake region; the crust-mantle boundary has an obvious block uplift and, in comparison with both sides, the top anomalous uplift of the upper mantle beneath the Tangshan block reaches to 10 km, and the upper mantle beneath has an anomalous heterogeneous structure; (4) beneath the Tangshan earthquake region, there are probably massive intrusions derived from the upper mantle, which form the low-velocity body in the upper and middle crust. Because of our results having much higher resolution than previous results, some new features of the crust and upper mantle velocity structure could be shown in this study; (5) the locations of destructive earthquakes are not random and are related closely to their deep structure of the crust and upper mantle. This provides a possibility of correctly estimating the location of destructive earthquakes. On the basis of our results, we discuss the dynamic genesis of the Tangshan earthquake. We consider that the main dynamic source for the Tangshan earthquake is the vertical

State of damage of radiation facilities in great Hanshin earthquake

International Nuclear Information System (INIS)

1995-01-01

The southern Hyogo Prefecture earthquake of magnitude 7.2 occurred in the early morning of January 17, 1995. The outline of the earthquake and dead and injured, the damages of buildings, life lines, roads, railways and harbors, liquefaction phenomena, the state of occurrence of fires and so on are reported. The districts where the earthquakes of magnitude 5 or stronger occurred, and the radiation facilities in those districts are shown. The state of damage of radiation facilities in past earthquakes is summarized. From January 17 to 19 after the earthquake, Science and Technology Agency gave necessary instruction to and heard the state of damage from 79 permitted facilities in the areas of magnitude 7 or 6 by telephone, and received the report that there was not the fear of radiation damage in all facilities. Also the state of damage of radiation facilities was investigated at the actual places, and the questionnaires on the state of radiation facilities and the action at the time of the earthquake were performed. The state of radiation facilities accompanying the earthquake is reported. The matters to be reflected to the countermeasures to earthquakes anew for the protection of facilities, communication system, facility checkup system and the resumption of use are pointed out. (K.I.)

Source to Sink Tectonic Fate of Large Oceanic Turbidite Systems and the Rupturing of Great and Giant Megathrust Earthquakes (Invited)

Science.gov (United States)

Scholl, D. W.; Kirby, S. H.; von Huene, R.

2010-12-01

OF THE TECTONIC SINK: Most great (Mw8.0 and larger) and giant (Mw8.5 and larger) megathrust earthquakes rupture along subduction zones fronted by thick sediment-filled (1 km and thicker) trench axes. For example, 75 percent of giant earthquakes broke at these trenches, and all earthquakes exceeding Mw9.0 ruptured adjacent to thickly sedimented trenches (2 km and thicker). Ruff (1989) first suggested that subduction of a thick section of sediment forms a relatively homogenous layer between the upper and lower plates that laterally smoothes the roughness of subducting sea-floor relief and rupture-arresting asperities. This condition favors long trench-parallel rupturing (more than 250 km), the hallmark of all great and giant megathrust earthquakes. In positive feedback, these huge strain-releasing shocks produce strong seafloor motions that trigger the flushing of sediment-charged turbidity currents to the trench axis and adjacent overflow fans. Subduction of these deposits recharges the subduction channel, sustaining conditions favorable to future great and giant megathrust ruptures. [Ruff, L., 1989, Do trench sediments affect great earthquakes occurrence in subduction zones, Pure and Applied Geophysics, v. 129, Nos. 1/2, p. 263-282].

Prediction of Global and Localized Damage and Future Reliability for RC Structures subject to Earthquakes

DEFF Research Database (Denmark)

Köyluoglu, H.U.; Nielsen, Søren R.K.; Cakmak, A.S.

1997-01-01

the arrival of the first earthquake from non-destructive vibration tests or via structural analysis. The previous excitation and displacement response time series is employed for the identification of the instantaneous softening using an ARMA model. The hysteresis parameters are updated after each earthquake....... The proposed model is next generalized for the MDOF system. Using the adapted models for the structure and the global damage state, the global damage in a future earthquake can then be estimated when a suitable earthquake model is applied. The performance of the model is illustrated on RC frames which were...

Prediction of Global and Localized Damage and Future Reliability for RC Structures subject to Earthquakes

DEFF Research Database (Denmark)

Köyluoglu, H.U.; Nielsen, Søren R.K.; Cakmak, A.S.

1994-01-01

the arrival of the first earthquake from non-destructive vibration tests or via structural analysis. The previous excitation and displacement response time series is employed for the identification of the instantaneous softening using an ARMA model. The hysteresis parameters are updated after each earthquake....... The proposed model is next generalized for the MDOF system. Using the adapted models for the structure and the global damage state, the global damage in a future earthquake can then be estimated when a suitable earthquake model is applied. The performance of the model is illustrated on RC frames which were...

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.

Proposal of new framework in nuclear emergency response based on problem in East Japan Great Earthquake

Energy Technology Data Exchange (ETDEWEB)

NONE

2013-08-15

In the nuclear emergency response activity in a East Japan great earthquake, the weakness the frame and the activity procedure (scheme) of the emergency response activity of our country that had been constructed after the accident of JCO became clear. Especially, it is necessary to recognize the importance of the enhancement of a prior plan after not only provision to response but also the damage to the environment occurs in the emergency for measures for restoration. Moreover, it is necessary to examine a concrete strategy about the management system strengthening of the radiation exposure at the accident. In this study, the experience and the finding in a East Japan great earthquake are arranged. The accident scenario that should be targeted is rearranged, and it proposes a new frame in the nuclear emergency response field through the requirement examinations such as the points of procedure, equipment, and the capital machine parts that lie a regulations frame of the nuclear emergency response, the activity frame of the nuclear emergency response, and materialized of the nuclear emergency response activity. (author)

Proposal of new framework in nuclear emergency response based on problem in East Japan Great Earthquake

International Nuclear Information System (INIS)

2013-01-01

In the nuclear emergency response activity in a East Japan great earthquake, the weakness the frame and the activity procedure (scheme) of the emergency response activity of our country that had been constructed after the accident of JCO became clear. Especially, it is necessary to recognize the importance of the enhancement of a prior plan after not only provision to response but also the damage to the environment occurs in the emergency for measures for restoration. Moreover, it is necessary to examine a concrete strategy about the management system strengthening of the radiation exposure at the accident. In this study, the experience and the finding in a East Japan great earthquake are arranged. The accident scenario that should be targeted is rearranged, and it proposes a new frame in the nuclear emergency response field through the requirement examinations such as the points of procedure, equipment, and the capital machine parts that lie a regulations frame of the nuclear emergency response, the activity frame of the nuclear emergency response, and materialized of the nuclear emergency response activity. (author)

Proposal of new framework in nuclear emergency response based on problem in East Japan Great Earthquake

International Nuclear Information System (INIS)

2012-01-01

In the nuclear emergency response activity in a East Japan great earthquake, the weakness the frame and the activity procedure (scheme) of the emergency response activity of our country that had been constructed after the accident of JCO became clear. Especially, it is necessary to recognize the importance of the enhancement of a prior plan after not only provision to response but also the damage to the environment occurs in the emergency for measures for restoration. Moreover, it is necessary to examine a concrete strategy about the management system strengthening of the radiation exposure at the accident. In this study, the experience and the finding in a East Japan great earthquake are arranged. The accident scenario that should be targeted is rearranged, and it proposes a new frame in the nuclear emergency response field through the requirement examinations such as the points of procedure, equipment, and the capital machine parts that lie a regulations frame of the nuclear emergency response, the activity frame of the nuclear emergency response, and materialized of the nuclear emergency response activity. (author)

Development of rupture process analysis method for great earthquakes using Direct Solution Method

Science.gov (United States)

Yoshimoto, M.; Yamanaka, Y.; Takeuchi, N.

2010-12-01

Conventional rupture process analysis methods using teleseismic body waves were based on ray theory. Therefore, these methods have the following problems in applying to great earthquakes such as 2004 Sumatra earthquake: (1) difficulty in computing all later phases such as the PP reflection phase, (2) impossibility of computing called “W phase”, the long period phase arriving before S wave, (3) implausibility of hypothesis that the distance is far enough from the observation points to the hypocenter compared to the fault length. To solve above mentioned problems, we have developed a new method which uses the synthetic seismograms computed by the Direct Solution Method (DSM, e.g. Kawai et al. 2006) as Green’s functions. We used the DSM software (http://www.eri.u-tokyo.ac.jp/takeuchi/software/) for computing the Green’s functions up to 1 Hz for the IASP91 (Kennett and Engdahl, 1991) model, and determined the final slip distributions using the waveform inversion method (Kikuchi et al. 2003). First we confirmed whether the Green’s functions computed by DSM were accurate in higher frequencies up to 1 Hz. Next we performed the rupture process analysis of this new method for Mw8.0 (GCMT) large Solomon Islands earthquake on April 1, 2007. We found that this earthquake consisted of two asperities and the rupture propagated across the subducting Sinbo ridge. The obtained slip distribution better correlates to the aftershock distributions than existing method. Furthermore, this new method keep same accuracy of existing method (which has the advantage of calculating) with respect to direct P-wave and reflection phases near the source, and also accurately calculate the later phases such a PP-wave.

Liquefaction macrophenomena in the great Wenchuan earthquake

Science.gov (United States)

Chen, Longwei; Yuan, Xiaoming; Cao, Zhenzhong; Hou, Longqing; Sun, Rui; Dong, Lin; Wang, Weiming; Meng, Fanchao; Chen, Hongjuan

2009-06-01

On May 12, 2008 at 14:28, a catastrophic magnitude M s 8.0 earthquake struck the Sichuan Province of China. The epicenter was located at Wenchuan (31.00°N, 103.40°E). Liquefaction macrophenomena and corresponding destruction was observed throughout a vast area of 500 km long and 200 km wide following the earthquake. This paper illustrates the geographic distribution of the liquefaction and the relationship between liquefaction behavior and seismic intensity, and summarizes the liquefaction macrophenomena, including sandboils and waterspouts, ground subsidence, ground fissures etc., and relevant liquefaction features. A brief summary of the structural damage caused by liquefaction is presented and discussed. Based on comparisons with liquefaction phenomena observed in the 1976 Tangshan and 1975 Haicheng earthquakes, preliminary analyses were performed, which revealed some new features of liquefaction behavior and associated issues arising from this event. The site investigation indicated that the spatial non-uniformity of liquefaction distribution was obvious and most of the liquefied sites were located in regions of seismic intensity VIII. However, liquefaction phenomena at ten different sites in regions of seismic intensity VI were also observed for the first time in China mainland. Sandboils and waterspouts ranged from centimeters to tens of meters, with most between 1 m to 3 m. Dramatically high water/sand ejections, e.g., more than 10 m, were observed at four different sites. The sand ejections included silty sand, fine sand, medium sand, course sand and gravel, but the ejected sand amount was less than that in the 1976 Tangshan earthquake. Possible liquefaction of natural gravel soils was observed for the first time in China mainland.

Preparing a population for an earthquake like Chi-Chi: The Great Southern California ShakeOut

Science.gov (United States)

Jones, Lucile M.; ,

2009-01-01

The Great Southern California ShakeOut was a week of special events featuring the largest earthquake drill in United States history. On November 13, 2008, over 5 million southern Californians pretended that a magnitude-7.8 earthquake had occurred and practiced actions that could reduce its impact on their lives. The primary message of the ShakeOut is that what we do now, before a big earthquake, will determine what our lives will be like after. The drill was based on a scenario of the impacts and consequences of such an earthquake on the Southern San Andreas Fault, developed by over 300 experts led by the U.S. Geological Survey in partnership with the California Geological Survey, the Southern California Earthquake Center, Earthquake Engineering Research Institute, lifeline operators, emergency services and many other organizations. The ShakeOut campaign was designed and implemented by earthquake scientists, emergency managers, sociologists, art designers and community participants. The means of communication were developed using results from sociological research on what encouraged people to take action. This was structured around four objectives: 1) consistent messages – people are more inclined to believe something when they hear the same thing from multiple sources; 2) visual reinforcement – people are more inclined to do something they see other people doing; 3) encourage “milling” or discussing contemplated action – people need to discuss an action with others they care about before committing to undertaking it; and 4) focus on concrete actions – people are more likely to prepare for a set of concrete consequences of a particular hazard than for an abstract concept of risk. The goals of the ShakeOut were established in Spring 2008 and were: 1) to register 5 million people to participate in the drill; 2) to change the culture of earthquake preparedness in southern California; and 3) to reduce earthquake losses in southern California. All of these

Preliminary earthquake locations in the Kenai Peninsula recorded by the MOOS Array and their relationship to structure in the 1964 great earthquake zone

Science.gov (United States)

Li, J.; Abers, G. A.; Christensen, D. H.; Kim, Y.; Calkins, J. A.

2011-12-01

Earthquakes in subduction zones are mostly generated at the interface between the subducting and overlying plates. In 2006-2009, the MOOS (Multidisciplinary Observations Of Subduction) seismic array was deployed around the Kenai Peninsula, Alaska, consisting of 34 broadband seismometers recording for 1-3 years. This region spans the eastern end of the Aleutian megathrust that ruptured in the 1964 Mw 9.2 great earthquake, the second largest recorded earthquake, and ongoing seismicity is abundant. Here, we report an initial analysis of seismicity recorded by MOOS, in the context of preliminary imaging. There were 16,462 events detected in one year from initial STA/LTA signal detections and subsequent event associations from the MOOS Array. We manually reviewed them to eliminate distant earthquakes and noise, leaving 11,879 local earthquakes. To refine this catalog, an adaptive auto-regressive onset estimation algorithm was applied, doubling the original dataset and producing 20,659 P picks and 22,999 S picks for one month (September 2007). Inspection shows that this approach lead to almost negligible false alarms and many more events than hand picking. Within the well-sampled part of the array, roughly 200 km by 300 km, we locate 250% more earthquakes for one month than the permanent network catalog, or 10 earthquakes per day on this patch of the megathrust. Although the preliminary locations of earthquakes still show some scatter, we can see a concentration of events in a ~20-km-wide belt, part of which can be interpreted as seismogenic thrust zone. In conjunction with the seismicity study, we are imaging the plate interface with receiver functions. The main seismicity zone corresponds to the top of a low-velocity layer imaged in receiver functions, nominally attributed to the top of the downgoing plate. As we refine velocity models and apply relative relocation algorithms, we expect to improve the precision of the locations substantially. When combined with image

Study of electrical power facilities and measures for planned outages in Japanese hemodialysis clinics after the Great East Japan Earthquake.

Science.gov (United States)

Ishida, Kai; Sawa, Manami; Fujiwara, Kousaku; Hirose, Minoru; Tsuruta, Harukazu; Takeuchi, Akihiro; Ikeda, Noriaki

2013-02-01

The Great East Japan Earthquake on 11 March 2011 caused major damage in northeastern Japan. The Kanto region experienced a massive electrical power shortage in the summer of 2011. A questionnaire was submitted to 354 hemodialysis clinics in Kanagawa prefecture and the Tokyo metropolitan area, excluding isolated islands, and 176 responses were analyzed (49.7%). The questions included evaluation of the availability of a private electricity generator, countermeasures in case of a planned outage, awareness of saving electricity, and improvement of safety of medical devices or electrical facilities after the earthquake. Only 12% of the clinics had private electricity generators and many clinics had no plans to introduce this facility. However, 96% of the clinics had established countermeasures to deal with a planned outage. Many clinics planned to provide dialysis on a different day or at a different time. All clinics had tried hard to establish procedures to save electricity in the summer of 2011, and 84% of the clinics had reconsidered and improved the safety of medical devices or electricity facilities after the earthquake. These results show that the awareness of crisis management was greatly improved in the wake of the earthquake. © 2012 The Authors. Therapeutic Apheresis and Dialysis © 2012 International Society for Apheresis.

Summary of November 2010 meeting to evaluate turbidite data for constraining the recurrence parameters of great Cascadia earthquakes for the update of national seismic hazard maps

Science.gov (United States)

Frankel, Arthur D.

2011-01-01

This report summarizes a meeting of geologists, marine sedimentologists, geophysicists, and seismologists that was held on November 18–19, 2010 at Oregon State University in Corvallis, Oregon. The overall goal of the meeting was to evaluate observations of turbidite deposits to provide constraints on the recurrence time and rupture extent of great Cascadia subduction zone (CSZ) earthquakes for the next update of the U.S. national seismic hazard maps (NSHM). The meeting was convened at Oregon State University because this is the major center for collecting and evaluating turbidite evidence of great Cascadia earthquakes by Chris Goldfinger and his colleagues. We especially wanted the participants to see some of the numerous deep sea cores this group has collected that contain the turbidite deposits. Great earthquakes on the CSZ pose a major tsunami, ground-shaking, and ground-failure hazard to the Pacific Northwest. Figure 1 shows a map of the Pacific Northwest with a model for the rupture zone of a moment magnitude Mw 9.0 earthquake on the CSZ and the ground shaking intensity (in ShakeMap format) expected from such an earthquake, based on empirical ground-motion prediction equations. The damaging effects of such an earthquake would occur over a wide swath of the Pacific Northwest and an accompanying tsunami would likely cause devastation along the Pacifc Northwest coast and possibly cause damage and loss of life in other areas of the Pacific. A magnitude 8 earthquake on the CSZ would cause damaging ground shaking and ground failure over a substantial area and could also generate a destructive tsunami. The recent tragic occurrence of the 2011 Mw 9.0 Tohoku-Oki, Japan, earthquake highlights the importance of having accurate estimates of the recurrence times and magnitudes of great earthquakes on subduction zones. For the U.S. national seismic hazard maps, estimating the hazard from the Cascadia subduction zone has been based on coastal paleoseismic evidence of great

Future Developments for the Earthquake Early Warning System following the 2011 off the Pacific Coast of Tohoku Earthquake

Science.gov (United States)

Yamada, M.; Mori, J. J.

2011-12-01

earthquake is to take into account the duration of waveforms and continuously update the magnitude estimate over at least 100 s One method, shown in Figure 1, uses the integral of the squared velocity over some duration of the S-wave arrival (Festa et al., 2008; Lancieri et al., 2011). The magnitude is estimated as greater than M8 30 seconds after the S-wave arrival, and close to M9 90 seconds later. Technical improvements of the current earthquake early warning system need to be made in anticipation of the next great earthquake, such as the expected Nankai earthquake.

Damage by the Great East Japan Earthquake and current status of the Sendai cyclotron

International Nuclear Information System (INIS)

Wakui, Takashi; Itoh, Masatoshi; Shimada, Kenzi; Yoshida, Hidetomo; Shinozuka, Tsutomu; Sakemi, Yasuhiro

2012-01-01

The Great East Japan Earthquake has inflicted damages on the accelerator facility of the Cyclotron and Radioisotope Center (CYRIC), Tohoku University. The K=110 MeV cyclotron was slanted due to the damage of props supporting the cyclotron. The cyclotron building has also been slightly inclined. This situation requires the re-alignment of all the beam transport line and the cyclotron. Some of the shield doors at experimental rooms were broken and blocked the entrance. The earthquake caused also a lot of damages to some components of the cyclotron as well as the beam transport lines, such as beam ducts, magnets, vacuum pumps and power supplies. Fortunately, no one was injured at CYRIC. The restoration work was started on July 2011 and will be completed by July 2012. This report describes the situation of damages and the current status of the restoration work. (author)

Earthquakes of Garhwal Himalaya region of NW Himalaya, India: A study of relocated earthquakes and their seismogenic source and stress

Science.gov (United States)

R, A. P.; Paul, A.; Singh, S.

2017-12-01

Since the continent-continent collision 55 Ma, the Himalaya has accommodated 2000 km of convergence along its arc. The strain energy is being accumulated at a rate of 37-44 mm/yr and releases at time as earthquakes. The Garhwal Himalaya is located at the western side of a Seismic Gap, where a great earthquake is overdue atleast since 200 years. This seismic gap (Central Seismic Gap: CSG) with 52% probability for a future great earthquake is located between the rupture zones of two significant/great earthquakes, viz. the 1905 Kangra earthquake of M 7.8 and the 1934 Bihar-Nepal earthquake of M 8.0; and the most recent one, the 2015 Gorkha earthquake of M 7.8 is in the eastern side of this seismic gap (CSG). The Garhwal Himalaya is one of the ideal locations of the Himalaya where all the major Himalayan structures and the Himalayan Seimsicity Belt (HSB) can ably be described and studied. In the present study, we are presenting the spatio-temporal analysis of the relocated local micro-moderate earthquakes, recorded by a seismicity monitoring network, which is operational since, 2007. The earthquake locations are relocated using the HypoDD (double difference hypocenter method for earthquake relocations) program. The dataset from July, 2007- September, 2015 have been used in this study to estimate their spatio-temporal relationships, moment tensor (MT) solutions for the earthquakes of M>3.0, stress tensors and their interactions. We have also used the composite focal mechanism solutions for small earthquakes. The majority of the MT solutions show thrust type mechanism and located near the mid-crustal-ramp (MCR) structure of the detachment surface at 8-15 km depth beneath the outer lesser Himalaya and higher Himalaya regions. The prevailing stress has been identified to be compressional towards NNE-SSW, which is the direction of relative plate motion between the India and Eurasia continental plates. The low friction coefficient estimated along with the stress inversions

Use of Fault Displacement Vector to Identify Future Zones of Seismicity: An Example from the Earthquakes of Nepal Himalayas.

Science.gov (United States)

Naim, F.; Mukherjee, M. K.

2017-12-01

Earthquakes occur due to fault slip in the subsurface. They can occur either as interplate or intraplate earthquakes. The region of study is the Nepal Himalayas that defines the boundary of Indian-Eurasian plate and houses the focus of the most devastating earthquakes. The aim of the study was to analyze all the earthquakes that occurred in the Nepal Himalayas upto May 12, 2015 earthquake in order to mark the regions still under stress and vulnerable for future earthquakes. Three different fault systems in the Nepal Himalayas define the tectonic set up of the area. They are: (1) Main Frontal Thrust(MFT), (2) Main Central Thrust(MCT) and (3) Main Boundary Thrust(MBT) that extend from NW to SE. Most of the earthquakes were observed to occur between the MBT and MCT. Since the thrust faults are dipping towards NE, the focus of most of the earthquakes lies on the MBT. The methodology includes estimating the dip of the fault by considering the depths of different earthquake events and their corresponding distance from the MBT. In order to carry out stress analysis on the fault, the beach ball diagrams associated with the different earthquakes were plotted on a map. Earthquakes in the NW and central region of the fault zone were associated with reverse fault slip while that on the South-Eastern part were associated with a strike slip component. The direction of net slip on the fault associated with the different earthquakes was known and from this a 3D slip diagram of the fault was constructed. The regions vulnerable for future earthquakes in the Nepal Himalaya were demarcated on the 3D slip diagram of the fault. Such zones were marked owing to the fact that the slips due to earthquakes cause the adjoining areas to come under immense stress and this stress is directly proportional to the amount of slip occuring on the fault. These vulnerable zones were in turn projected on the map to show their position and are predicted to contain the epicenter of the future earthquakes.

Design and investigation of a continuous radon monitoring network for earthquake precursory process in Great Tehran

International Nuclear Information System (INIS)

Negarestani, A.; Namvaran, M.; Hashemi, S.M.; Shahpasandzadeh, M.; Fatemi, S.J.; Alavi, S.A.; Mokhtari, M.

2014-01-01

Earthquakes usually occur after some preliminary anomalies in the physical and chemical characteristics of environment and earth interior. Construction of the models which can explain these anomalies, prompt scientists to monitor geophysical and geochemical characteristics in the seismic areas for earthquake prediction. A review of studies has been done so far, denoted that radon gas shows more sensitivity than other geo-gas as a precursor. Based on previous researches, radon is a short-term precursor of earthquake from time point of view. There are equal experimental equations about the relation between earthquake magnitude and its effective distance on radon concentration variations. In this work, an algorithm based on Dobrovolsky equation (D=10 0.43M ) with defining the Expectation and Investigation circles for great Tehran has been used. Radon concentration was measured with RAD7 detector in the more than 40 springs. Concentration of radon in spring, spring discharge, water temperature and the closeness of spring location to active faults, have been considered as the significant factors to select the best spring for a radon continuous monitoring site implementation. According to these factors, thirteen springs have been selected as follow: Bayjan, Mahallat-Hotel, Avaj, Aala, Larijan, Delir, Lavij, Ramsar, Semnan, Lavieh, Legahi, Kooteh-Koomeh and Sarein. (author)

Two cases of severe pneumonia after the 2011 Great East Japan Earthquake

Directory of Open Access Journals (Sweden)

Shigeatu Endo

2012-12-01

Full Text Available In 2011, during the Great East Japan Earthquake and tsunami, 90% of victims died from drowning. We report on two tsunami survivors with severe pneumonia potentially caused by Legionella pneumophila. Both victims aspirated a large quantity of contaminated water; sand, mud and a variety of microbes were thought to have entered into their lower respiratory tracts. One patient had a mycotic intracranial aneurysm; the other patient had co-infections with several organisms, including Scedosporium species. Although scedosporiosis is a relatively rare infectious disease, symptoms are progressive and prognosis is poor. These pathogens are not specific for tsunami lung, but are reported causative agents for pneumonia after near-drowning.

Survey of awareness and analyses of related factors to volunteer activities of pharmacy students after the Great East Japan Earthquake

OpenAIRE

小武家, 優子; 吉田, 健; 吉武, 毅人

2012-01-01

The Great East Japan Earthquake occurred on March 11, 2011. At the time of the earthquake, pharmacist and pharmacy students engaged in volunteer activities such as providing disaster medicine and relief supplies to disaster areas. Questionnaire survey for pharmacy students were carried out in order to clarify awareness to volunteer activities for disaster areas and to use data as a basis of Service-Learning in the 6 years pharmacy education. We divided subjects into pharmacy students those wo...

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.

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.

Passive seismic monitoring of natural and induced earthquakes: case studies, future directions and socio-economic relevance

Science.gov (United States)

Bohnhoff, Marco; Dresen, Georg; Ellsworth, William L.; Ito, Hisao; Cloetingh, Sierd; Negendank, Jörg

2010-01-01

An important discovery in crustal mechanics has been that the Earth’s crust is commonly stressed close to failure, even in tectonically quiet areas. As a result, small natural or man-made perturbations to the local stress field may trigger earthquakes. To understand these processes, Passive Seismic Monitoring (PSM) with seismometer arrays is a widely used technique that has been successfully applied to study seismicity at different magnitude levels ranging from acoustic emissions generated in the laboratory under controlled conditions, to seismicity induced by hydraulic stimulations in geological reservoirs, and up to great earthquakes occurring along plate boundaries. In all these environments the appropriate deployment of seismic sensors, i.e., directly on the rock sample, at the earth’s surface or in boreholes close to the seismic sources allows for the detection and location of brittle failure processes at sufficiently low magnitude-detection threshold and with adequate spatial resolution for further analysis. One principal aim is to develop an improved understanding of the physical processes occurring at the seismic source and their relationship to the host geologic environment. In this paper we review selected case studies and future directions of PSM efforts across a wide range of scales and environments. These include induced failure within small rock samples, hydrocarbon reservoirs, and natural seismicity at convergent and transform plate boundaries. Each example represents a milestone with regard to bridging the gap between laboratory-scale experiments under controlled boundary conditions and large-scale field studies. The common motivation for all studies is to refine the understanding of how earthquakes nucleate, how they proceed and how they interact in space and time. This is of special relevance at the larger end of the magnitude scale, i.e., for large devastating earthquakes due to their severe socio-economic impact.

Influence of living environment and subjective economic hardship on new-onset of low back pain for survivors of the Great East Japan Earthquake.

Science.gov (United States)

Yabe, Yutaka; Hagiwara, Yoshihiro; Sekiguchi, Takuya; Sugawara, Yumi; Sato, Mari; Kanazawa, Kenji; Koide, Masashi; Itaya, Nobuyuki; Tsuchiya, Masahiro; Tsuji, Ichiro; Itoi, Eiji

2017-01-01

The Great East Japan Earthquake and subsequent tsunami devastated the northeastern part of Japan. Low back pain is thought to increase after a natural disaster and is related to various factors. The aim of this study was to examine the influencing factors of "Living environment" and "Subjective economic hardship" on new-onset of low back pain in the chronic phase for the survivors of the earthquake evaluated by a self-report questionnaire. A panel study was conducted with the Great East Japan Earthquake survivors at 2 and 3 years after the disaster. New-onset of low back pain was defined as low back pain absent at the 1st period (2 years after the earthquake) and present at the 2nd period (3 years after the earthquake). Living environment was divided into 4 categories (1. Living in the same house as before the earthquake, 2. Living in a prefabricated house, 3. Living in a new house, 4. Others: Living in an apartment, house of relatives or acquaintance). Subjective economic hardship was obtained using the following self-report question: "How do you feel about the current economic situation of your household?" The response alternatives were "Normal", "A little bit hard", "Hard", and "Very hard". A univariate and multivariate logistic regression models were used. 1357 survivors consented to join this study. There was no significant association between new-onset of low back pain and living environment. There was significant association between new-onset of low back pain and "A little hard" (OR = 1.6, 95% CI = 1.07-2.40), "Hard" (OR = 2.2, 95% CI = 1.56-3.74), and "Very hard" (OR = 3.19, 95% CI = 1.84-5.53) in subjective economic hardship. Subjective economic hardship was significantly associated with new-onset of low back pain in the chronic phase for survivors of the Great East Japan Earthquake. Copyright © 2016. Published by Elsevier B.V.

Alterations in physique among young children after the Great East Japan Earthquake: Results from a nationwide survey.

Science.gov (United States)

Kikuya, Masahiro; Matsubara, Hiroko; Ishikuro, Mami; Sato, Yuki; Obara, Taku; Metoki, Hirohito; Isojima, Tsuyoshi; Yokoya, Susumu; Kato, Noriko; Tanaka, Toshiaki; Chida, Shoichi; Ono, Atsushi; Hosoya, Mitsuaki; Yokomichi, Hiroshi; Yamagata, Zentaro; Tanaka, Soichiro; Kure, Shigeo; Kuriyama, Shinichi

2017-10-01

Data for earthquake-related alterations in physique among young children in developed countries is lacking. The Great East Japan Earthquake caused severe damage in Iwate, Miyagi, and Fukushima Prefectures in northeastern Japan. We retrospectively obtained anthropometric measurements in nursery school from 40,046 (cohort 1, historical control) and 53,492 (cohort 2) children aged 3.5-4.5 years without overweight in October 2008, and in October 2010, respectively. At the time of the earthquake in March, 2011, children in cohort 1 had already graduated from nursery school; however, children in cohort 2 were still enrolled in nursery school at this time. We compared the onset of overweight at 1 year after the baseline between children enrolled in their school located in one of the three target prefectures versus those in other prefectures using a logistic regression model, with adjustment for sex, age, history of disease, and obesity index at baseline. Overweight was defined as an obesity index of >+15%, which was calculated as (weight minus sex- and height-specific standard weight)/sex- and height-specific standard weight. The odds ratio (OR) for the onset of overweight in the three target prefectures was significant in cohort 2 (OR 1.25; 95% confidence interval [CI], 1.01-1.55) but not in cohort 1. When the two cohort were pooled (n = 93,538), the OR of the interaction term for school location × cohort was significant (OR 1.56; 95% CI, 1.09-2.23). Incident overweight in young children was significantly more common in the three prefectures affected by the Great East Japan Earthquake than in other prefectures after the disaster. Copyright © 2017 The Authors. Production and hosting by Elsevier B.V. All rights reserved.

Japanese energy balances after the Great East Japan Earthquake

International Nuclear Information System (INIS)

Tsuzuki, Kazuhiro; Moriyama, Ryo; Ishimoto, Yuki; Tomikatsu, Koji; Hagiwara, Naoto

2012-01-01

After the Great East Japan Earthquake, disaster response and risk of nuclear accident became a new issue and the public against nuclear power was increasing with knowing a long-term period required for restoration from Fukushima accident. This article described effects of 'de-nuclear power' policy with no additional plants on energy balances in 2030 and 2050 with simulated energy model based on government's long-term energy supply-demand outlook issued in 2009. Main assumed conditions were as follows; (1) nuclear power of case B) 40 years operation and C) 60 years operation, (2) share of photovoltaic and wind power was assumed to be 9% of total power generation and the same as planned before the earthquake disaster, which could not replace nuclear power and (3) final consumption of case 2) 8% saving and 3) 20% saving. Effects of 'de-nuclear power' in 2030 were (1) CO 2 emission difference between B) and C) was 50 Mt and (2) estimated cost increase between B) and C) was 0.1 T yen/year for CO 2 emission, 1 T yen/year for LNG procurement and 2.4 T yen for thermal power construction. Energy balances in 2050 were much influenced by trend of renewable energy technology development and fossil energy procurement and use. Sophisticated power change measures using storage battery for renewable energy should be developed, otherwise if power change were dealt with thermal power, share would be limited to 15-20% of total power generation. If CO 2 emission in 2050 was limited to 50% instead of formally announced 80% of CO 2 emission in 1990, share of non-fossil power (nuclear power + renewable energy) became almost 100% for case 3). Base technology of nuclear power should remain as option for the case where fossil energy procurement and CO 2 emission limit became restrictive in 2050. (T. Tanaka)

Changes in suicide rates in disaster-stricken areas following the Great East Japan Earthquake and their effect on economic factors: an ecological study.

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Orui, Masatsugu; Harada, Shuichiro; Hayashi, Mizuho

2014-11-01

Devastating disasters may increase suicide rates due to mental distress. Previous domestic studies have reported decreased suicide rates among men following disasters. Few reports are available regarding factors associated with disasters, making it difficult to discuss how these events affect suicide rates. This study aimed to observe changes in suicide rates in disaster-stricken and neighboring areas following the Great East Japan Earthquake, and examine associations between suicide rates and economic factors. Monthly suicide rates were observed from March 2009 to February 2013, during which time the earthquake occurred on March, 2011. Data were included from disaster-stricken (Iwate, Miyagi, and Fukushima Prefectures) and neighboring (control: Aomori, Akita, and Yamagata Prefectures) areas. The association between changes in suicide rates and economic variables was evaluated based on the number of bankruptcy cases and ratio of effective job offers. In disaster-stricken areas, post-disaster male suicide rates decreased during the 24 months following the earthquake. This trend differed relative to control areas. Female suicide rates increased during the first seven months. Multiple regression analysis showed that bankruptcy cases (β = 0.386, p = 0.038) and ratio of effective job offers (β = -0.445, p = 0.018) were only significantly associated with male post-disaster suicide rates in control areas. Post-disaster suicide rates differed by gender following the earthquake. Our findings suggest that considering gender differences might be important for developing future post-disaster suicide prevention measures. This ecological study revealed that increasing effective job offers and decreasing bankruptcy cases can affect protectively male suicide rates in control areas.

Sediment gravity flows triggered by remotely generated earthquake waves

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Johnson, H. Paul; Gomberg, Joan S.; Hautala, Susan L.; Salmi, Marie S.

2017-06-01

Recent great earthquakes and tsunamis around the world have heightened awareness of the inevitability of similar events occurring within the Cascadia Subduction Zone of the Pacific Northwest. We analyzed seafloor temperature, pressure, and seismic signals, and video stills of sediment-enveloped instruments recorded during the 2011-2015 Cascadia Initiative experiment, and seafloor morphology. Our results led us to suggest that thick accretionary prism sediments amplified and extended seismic wave durations from the 11 April 2012 Mw8.6 Indian Ocean earthquake, located more than 13,500 km away. These waves triggered a sequence of small slope failures on the Cascadia margin that led to sediment gravity flows culminating in turbidity currents. Previous studies have related the triggering of sediment-laden gravity flows and turbidite deposition to local earthquakes, but this is the first study in which the originating seismic event is extremely distant (> 10,000 km). The possibility of remotely triggered slope failures that generate sediment-laden gravity flows should be considered in inferences of recurrence intervals of past great Cascadia earthquakes from turbidite sequences. Future similar studies may provide new understanding of submarine slope failures and turbidity currents and the hazards they pose to seafloor infrastructure and tsunami generation in regions both with and without local earthquakes.

The Alaska earthquake, March 27, 1964: lessons and conclusions

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Eckel, Edwin B.

1970-01-01

local waves. Better earthquake-hazard maps, based on improved knowledge of regional geology, fault behavior, and earthquake mechanisms, are needed for the entire country. Their preparation will require the close collaboration of engineers, seismologists, and geologists. Geologic maps of all inhabited places in earthquake-prone parts of the country are also needed by city planners and others, because the direct relationship between local geology and potential earthquake damage is now well understood. Improved and enlarged nets of earthquake-sensing instruments, sited in relation to known geology, are needed, as are many more geodetic and hydrographic measurements. Every large earthquake, wherever located, should be regarded as a full-scale laboratory experiment whose study can give scientific and engineering information unobtainable from any other source. Plans must be made before the event to insure staffing, funding, and coordination of effort for the scientific and engineering study of future earthquakes. Advice of earth scientists and engineers should be used in the decision-making processes involved in reconstruction after any future disastrous earthquake, as was done after the Alaska earthquake. The volume closes with a selected bibliography and a comprehensive index to the entire series of U.S. Geological Survey Professional Papers 541-546. This is the last in a series of six reports that the U.S. Geological Survey published on the results of a comprehensive geologic study that began, as a reconnaissance survey, within 24 hours after the March 27, 1964, Magnitude 9.2 Great Alaska Earthquake and extended, as detailed investigations, through several field seasons. The 1964 Great Alaska earthquake was the largest earthquake in the U.S. since 1700. Professional Paper 546, in 1 part, describes Lessons and Conclusions.

Great earthquakes and slow slip events along the Sagami trough and outline of the Kanto Asperity Project

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Kobayashi, R.; Yamamoto, Y.; Sato, T.; Shishikura, M.; Ito, H.; Shinohara, M.; Kawamura, K.; Shibazaki, B.

2010-12-01

The Kanto region is one of the most densely populated urban areas in the world. Complicated plate configurations are due to T-T-T type triple junction, island arc-island arc collision zone, and very shallow angle between axis of the Sagami trough and subducting direction. Great earthquakes along the Sagami trough have repeatedly occurred. The 1703 Genroku and 1923 (Taisho) Kanto earthquakes caused severe damages in the Tokyo metropolitan area. Intriguingly slow slip events have also repeatedly occurred in an area adjacent to the asperities of the great earthquakes, off Boso peninsula (e.g., Ozawa et al 2007). In the cases of the Nankai and Cascadia subduction zones, slow slip events occur at deeper levels than the asperity, in a transition zone between the asperity and a region of steady slip. In contrast, slow slip events in the Kanto region have occurred at relatively shallow depths, at the same level as the asperity, raising the possibility of friction controlled by different conditions to those (temperature and pressure) encountered at Nankai and Cascadia. We focus on three different types of seismic events occurring repeatedly at the almost same depth of the seismogenic zone along the Sagami trough (5-20 km) (1) The 1923 M~7.9 Taisho earthquake, located in Sagami Bay. Maximum slip is about 6 m, the recurrence interval is 200-400 yr, and the coupling rate is 80-100% (“coupling rates” = “slip amounts during earthquakes or slow-slip events” / [“rate of motion of the Philippine Sea Plate” - “recurrence interval”]) . (2) The 1703 M~8.2 Genroku earthquake, located in Sagami Bay, but also extending to the southern part of Boso Peninsula. Maximum slip is 15-20 m, the recurrence interval is ~2000 yr, and the coupling rate at the southern part of the Boso Peninsula is 10-30%. (3) Boso slow-slip events, located southeast of Boso Peninsula. Maximum slip is 15-20 cm over ~10 days, the recurrence interval is 5-6 yr, and the coupling rate is 70

Source Parameter Inversion for Recent Great Earthquakes from a Decade-long Observation of Global Gravity Fields

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Han, Shin-Chan; Riva, Ricccardo; Sauber, Jeanne; Okal, Emile

2013-01-01

We quantify gravity changes after great earthquakes present within the 10 year long time series of monthly Gravity Recovery and Climate Experiment (GRACE) gravity fields. Using spherical harmonic normal-mode formulation, the respective source parameters of moment tensor and double-couple were estimated. For the 2004 Sumatra-Andaman earthquake, the gravity data indicate a composite moment of 1.2x10(exp 23)Nm with a dip of 10deg, in agreement with the estimate obtained at ultralong seismic periods. For the 2010 Maule earthquake, the GRACE solutions range from 2.0 to 2.7x10(exp 22)Nm for dips of 12deg-24deg and centroid depths within the lower crust. For the 2011 Tohoku-Oki earthquake, the estimated scalar moments range from 4.1 to 6.1x10(exp 22)Nm, with dips of 9deg-19deg and centroid depths within the lower crust. For the 2012 Indian Ocean strike-slip earthquakes, the gravity data delineate a composite moment of 1.9x10(exp 22)Nm regardless of the centroid depth, comparing favorably with the total moment of the main ruptures and aftershocks. The smallest event we successfully analyzed with GRACE was the 2007 Bengkulu earthquake with M(sub 0) approx. 5.0x10(exp 21)Nm. We found that the gravity data constrain the focal mechanism with the centroid only within the upper and lower crustal layers for thrust events. Deeper sources (i.e., in the upper mantle) could not reproduce the gravity observation as the larger rigidity and bulk modulus at mantle depths inhibit the interior from changing its volume, thus reducing the negative gravity component. Focal mechanisms and seismic moments obtained in this study represent the behavior of the sources on temporal and spatial scales exceeding the seismic and geodetic spectrum.

Monitoring of the future strong Vrancea events by using the CN formal earthquake prediction algorithm

International Nuclear Information System (INIS)

Moldoveanu, C.L.; Novikova, O.V.; Panza, G.F.; Radulian, M.

2003-06-01

The preparation process of the strong subcrustal events originating in Vrancea region, Romania, is monitored using an intermediate-term medium-range earthquake prediction method - the CN algorithm (Keilis-Borok and Rotwain, 1990). We present the results of the monitoring of the preparation of future strong earthquakes for the time interval from January 1, 1994 (1994.1.1), to January 1, 2003 (2003.1.1) using the updated catalogue of the Romanian local network. The database considered for the CN monitoring of the preparation of future strong earthquakes in Vrancea covers the period from 1966.3.1 to 2003.1.1 and the geographical rectangle 44.8 deg - 48.4 deg N, 25.0 deg - 28.0 deg E. The algorithm correctly identifies, by retrospective prediction, the TJPs for all the three strong earthquakes (Mo=6.4) that occurred in Vrancea during this period. The cumulated duration of the TIPs represents 26.5% of the total period of time considered (1966.3.1-2003.1.1). The monitoring of current seismicity using the algorithm CN has been carried out since 1994. No strong earthquakes occurred from 1994.1.1 to 2003.1.1 but the CN declared an extended false alarm from 1999.5.1 to 2000.11.1. No alarm has currently been declared in the region (on January 1, 2003), as can be seen from the TJPs diagram shown. (author)

Scientific Information Platform for the 2008 Great Wenchuan Earthquake

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Liang, C.

2012-12-01

The 2008 MS 8.0 Wenchuan earthquake is one of the deadliest in recent human history. This earthquake has not just united the whole world to help local people to lead their life through the difficult time, it has also fostered significant global cooperation to study this event from various aspects: including pre-seismic events (such as the seismicity, gravity, electro-magnetic fields, well water level, radon level in water etc), co-seismic events (fault slipping, landslides, man-made structure damages etc) and post-seismic events (such as aftershocks, well water level changing etc) as well as the disaster relief efforts. In the last four years, more than 300 scientific articles have been published on peer-reviewed journals, among them about 50% are published in Chinese, 30% in English, and about 20% in both languages. These researches have advanced our understanding of earthquake science in general. It has also sparked open debates in many aspects. Notably, the role of the Zipingpu reservoir (built not long ago before the earthquake) in the triggering of this monstrous earthquake is still one of many continuing debates. Given that all these articles are ssporadically spread out on different journals and numerous issues and in different languages, it can be very inefficient, sometimes impossible, to dig out the information that are in need. The Earthquake Research Group in the Chengdu University of Technology (ERGCDUT) has initiated an effort to develop an information platform to collect and analyze scientific research on or related to this earthquake, the hosting faults and the surrounding tectonic regions. A preliminary website has been setup for this purpose: http://www.wenchuaneqresearch.org. Up to this point (July 2012), articles published in 6 Chinese journals and 7 international journals have been collected. Articles are listed journal by journal, and also grouped by contents into four major categories, including pre-seismic events, co-seismic events, post

Coseismic and postseismic deformation of the great 2004 Sumatra-Andaman earthquake

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Hughes, Kristin Leigh Hellem

studies (Masterlark and Hughes, 2008; Hughes et al., 2010). Rapidly advancing computational capabilities recently placed FEMs at the forefront of earthquake deformation analyses. The results and conclusions of this study will strongly influence future analyses of coseismic and postseismic deformation, stress, pore pressure, and tsunami genesis.

Influence of living environments and working status on low back pain for survivors of the Great East Japan Earthquake.

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Hagiwara, Yoshihiro; Yabe, Yutaka; Sugawara, Yumi; Sato, Mari; Watanabe, Takashi; Kanazawa, Kenji; Sonofuchi, Kazuaki; Koide, Masashi; Sekiguchi, Takuya; Tsuchiya, Masahiro; Tsuji, Ichiro; Itoi, Eiji

2016-03-01

The Great East Japan Earthquake and devastating Tsunami caused irreparable damage on the northeastern coast of Japan. This study aimed to examine the influencing factors of "Living environment" and "Working status" on low back pain for the survivors of the earthquake evaluated by a self-report questionnaire. Between 2011 and 2013, survivors replied to the self-report questionnaire, and 986 people consented to join this study. The living environment was divided into 3 categories (1. Living in the same house as before the earthquake, 2. Living in a safe shelter or temporary small house, 3. Living in a house of relatives or apartment house) and working status was divided into 5 categories (1. Unemployed before the earthquake, 2. Unemployed after the earthquake, 3. Decrease in income, 4. Different occupation after the earthquake, 5. The same occupation as before the earthquake). Age, gender, living areas, past history of arthritis, arthropathy, osteoporosis, sleep disturbance, psychological distress, and economic status were considered as confounding factors. Generalized estimating regression models with logit link function were used because outcome variables are repeatedly measured and binomial. We evaluated the correlation between the presence/severity of low back pain over time and housing status/working status at 1 year after the earthquake. There were no significant differences between age, gender, living areas, working status, or living environment before or after the earthquake. There was no significant difference in the risk of having low back pain in living environment or gender. There was significant difference in the risk of having low back pain in those with "Decrease in income" (OR = 1.93, 95% CI = 1.23-3.03) and "The same occupation as before the earthquake" (OR = 1.67, 95% CI = 1.1-2.52). Though living environment has little effect, "Decrease in income" and "The same occupation as before the earthquake" have strong influences on low back pain

Post-Traumatic Stress Symptoms and Burnout Among Medical Rescue Workers 4 Years After the Great East Japan Earthquake: A Longitudinal Study.

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Kawashima, Yuzuru; Nishi, Daisuke; Noguchi, Hiroko; Usuki, Masato; Yamashita, Akihiro; Koido, Yuichi; Okubo, Yoshiro; Matsuoka, Yutaka J

2016-12-01

This study aimed to evaluate factors associated with post-traumatic stress disorder (PTSD) symptoms and burnout 4 years after the Great East Japan Earthquake among medical rescue workers in Disaster Medical Assistance Teams (DMATs). We examined participants' background characteristics, prior health condition, rescue work experiences, and the Peritraumatic Distress Inventory (PDI) score at 1 month after the earthquake. Current psychological condition was assessed by the Impact of Event Scale-Revised and Maslach Burnout Inventory administered 4 years after the earthquake. By applying univariate and multivariate linear regression analyses, we assessed the relative value of the PDI and other baseline variables for PTSD symptoms and burnout at 4 years after the earthquake. We obtained baseline data from 254 participants during April 2 to 22, 2011. Of the 254 participants, 188 (74.0%) completed the follow-up assessment. PDI score 1 month after the earthquake was associated with symptoms of PTSD (β=0.35, Pburnout (β=0.21, PStress before deployment was a related factor for burnout 4 years after the earthquake in these medical rescue workers (β=2.61, Pstress prior to deployment (Disaster Med Public Health Preparedness. 2016;10:848-853).

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

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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.

Results of the Regional Earthquake Likelihood Models (RELM) test of earthquake forecasts in California.

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Lee, Ya-Ting; Turcotte, Donald L; Holliday, James R; Sachs, Michael K; Rundle, John B; Chen, Chien-Chih; Tiampo, Kristy F

2011-10-04

The Regional Earthquake Likelihood Models (RELM) test of earthquake forecasts in California was the first competitive evaluation of forecasts of future earthquake occurrence. Participants submitted expected probabilities of occurrence of M ≥ 4.95 earthquakes in 0.1° × 0.1° cells for the period 1 January 1, 2006, to December 31, 2010. Probabilities were submitted for 7,682 cells in California and adjacent regions. During this period, 31 M ≥ 4.95 earthquakes occurred in the test region. These earthquakes occurred in 22 test cells. This seismic activity was dominated by earthquakes associated with the M = 7.2, April 4, 2010, El Mayor-Cucapah earthquake in northern Mexico. This earthquake occurred in the test region, and 16 of the other 30 earthquakes in the test region could be associated with it. Nine complete forecasts were submitted by six participants. In this paper, we present the forecasts in a way that allows the reader to evaluate which forecast is the most "successful" in terms of the locations of future earthquakes. We conclude that the RELM test was a success and suggest ways in which the results can be used to improve future forecasts.

The great East Japan earthquake of March 11, 2011, from the vantage point of blood banking and transfusion medicine.

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Nollet, Kenneth E; Ohto, Hitoshi; Yasuda, Hiroyasu; Hasegawa, Arifumi

2013-01-01

The Great East Japan Earthquake of March 11, 2011, and subsequent tsunami took nearly 20 000 lives in Tohoku, the northeastern part of Japan's main island. Most victims were either carried away by the tsunami or drowned. The ability to collect blood was disrupted on the Pacific coast of Tohoku. Inland areas were less affected, but allogeneic blood collected in Tohoku is tested at the Miyagi Red Cross Blood Center (Miyagi Center) in the coastal city of Sendai. Miyagi Center was damaged and could not test for 2 months. The aims of this study are as follows: (1) to assess transfusion practice at 8 disaster response hospitals in Tohoku's Fukushima Prefecture, for equal intervals before and after March 11, 2011; (2) to report activities related to blood collection and distribution in response to the disaster; and (3) to describe the Great East Japan Earthquake in the context of other disasters. Data were collected through a survey of transfusion services at 8 major disaster response hospitals, communication at transfusion conferences, and literature review. Transfused patients and units transfused were about 70% and 60% of normal in the surveyed hospitals because this was a disaster of mass casualty rather than mass injury, and patients requiring chronic care were evacuated out. A nationally coordinated effort allowed excess blood collected outside Tohoku to be transported in, despite infrastructure damage. Japan's national system of blood collection and distribution responded effectively to local needs after the Great East Japan Earthquake. Disasters such as Japan's 3.11 should guide discourse about emergency preparedness and centralization of services. Copyright © 2013. Published by Elsevier Inc.

Survey of damage to 602 MR scanners after the Great East Japan Earthquake

International Nuclear Information System (INIS)

Nakai, Toshiharu; Yamaguchi-Sekino, Sachiko; Tsuchihashi, Toshio

2013-01-01

An earthquake of 9.0 magnitude, the largest in modern Japanese history, struck east Japan on March 11, 2011. We investigated hazards and observations related to magnetic resonance (MR) scanners in this earthquake to evaluate potential risks and consider further prevention or minimization of damage from and injury of patients in such large earthquakes. The investigation team funded by MHLW sent questionnaires to the 984 facilities with installed MR scanners in the 7 prefectures of east Japan (Iwate, Miyagi, Fukushima, Ibaraki, Chiba, Tokyo, Saitama) and collected 458 responses (46.6%) with information on 602 MR scanners (144 units≤0.5 tesla; 31 one-T units; 371 1.5-T units; and 56 units≥3 T). Significant differences in damage were observed between seismic scale 5 and 6 (χ 2 test, P<0.001 for all items of damage checked). The frequencies of typical damage were displacement of magnets (12.4%), failure of the chiller or air conditioning (9.6%), rapid decrease in liquid helium (8.4%), damage to magnet enclosure and its equipment (7.6%), damage to shielding of the MR scanner room (6.1%), damage to the quench duct (4.5%), breakage of devices anchoring system cabinets (4.4%), damage to the magnet base (3.9%), and flying of metal components (1.5%). Twelve facilities reported flooding by the subsequent tsunami, and quench was confirmed in 19 facilities. No fire damage was reported. It was confirmed that no one was severely injured in MR scanners, and base isolation of the building was very useful in completely preventing damage even at seismic scale 7. In the future, training for evacuation and establishment of a standard protocol for emergency shutdown of MR scanners, onsite checking by MR operators, and emergency power plant equipment to maintain chiller for MR scanners will further ensure MR safety in an earthquake. (author)

Real-time earthquake source imaging: An offline test for the 2011 Tohoku earthquake

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Zhang, Yong; Wang, Rongjiang; Zschau, Jochen; Parolai, Stefano; Dahm, Torsten

2014-05-01

In recent decades, great efforts have been expended in real-time seismology aiming at earthquake and tsunami early warning. One of the most important issues is the real-time assessment of earthquake rupture processes using near-field seismogeodetic networks. Currently, earthquake early warning systems are mostly based on the rapid estimate of P-wave magnitude, which contains generally large uncertainties and the known saturation problem. In the case of the 2011 Mw9.0 Tohoku earthquake, JMA (Japan Meteorological Agency) released the first warning of the event with M7.2 after 25 s. The following updates of the magnitude even decreased to M6.3-6.6. Finally, the magnitude estimate stabilized at M8.1 after about two minutes. This led consequently to the underestimated tsunami heights. By using the newly developed Iterative Deconvolution and Stacking (IDS) method for automatic source imaging, we demonstrate an offline test for the real-time analysis of the strong-motion and GPS seismograms of the 2011 Tohoku earthquake. The results show that we had been theoretically able to image the complex rupture process of the 2011 Tohoku earthquake automatically soon after or even during the rupture process. In general, what had happened on the fault could be robustly imaged with a time delay of about 30 s by using either the strong-motion (KiK-net) or the GPS (GEONET) real-time data. This implies that the new real-time source imaging technique is helpful to reduce false and missing warnings, and therefore should play an important role in future tsunami early warning and earthquake rapid response systems.

[Expression of negative emotional responses to the 2011 Great East Japan Earthquake: Analysis of big data from social media].

Science.gov (United States)

Miura, Asako; Komori, Masashi; Matsumura, Naohiro; Maeda, Kazutoshi

2015-06-01

In this article, we investigated the expression of emotional responses to the 2011 Great East Japan Earthquake by analyzing the frequency of negative emotional terms in tweets posted on Twitter, one of the most popular social media platforms. We focused on differences in time-series variations and diurnal changes between two kinds of disasters: natural disasters (earthquakes and tsunamis) and nuclear accidents. The number of tweets containing negative emotional responses increased sharply shortly after the first huge earthquake and decreased over time, whereas tweets about nuclear accidents showed no correlation with elapsed time. Expressions of anxiety about natural disasters had a circadian rhythm, with a peak at midnight, whereas expressions of anger about the nuclear accident were highly sensitive to critical events related to the accident. These findings were discussed in terms of similarities and differences compared to earlier studies on emotional responses in social media.

Life-event stress induced by the Great East Japan Earthquake was associated with relapse in ulcerative colitis but not Crohn's disease: a retrospective cohort study

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Shiga, Hisashi; Miyazawa, Teruko; Kinouchi, Yoshitaka; Takahashi, Seiichi; Tominaga, Gen; Takahashi, Hiroki; Takagi, Sho; Obana, Nobuya; Kikuchi, Tatsuya; Oomori, Shinya; Nomura, Eiki; Shiraki, Manabu; Sato, Yuichirou; Takahashi, Shuichiro; Umemura, Ken; Yokoyama, Hiroshi; Endo, Katsuya; Kakuta, Yoichi; Aizawa, Hiroki; Matsuura, Masaki; Kimura, Tomoya; Kuroha, Masatake; Shimosegawa, Tooru

2013-01-01

Objective Stress is thought to be one of the triggers of relapses in patients with inflammatory bowel disease (IBD). We examined the rate of relapse in IBD patients before and after the Great East Japan Earthquake. Design A retrospective cohort study. Settings 13 hospitals in Japan. Participants 546 ulcerative colitis (UC) and 357 Crohn's disease (CD) patients who received outpatient and inpatient care at 13 hospitals located in the area that were seriously damaged by the earthquake. Data on patient's clinical characteristics, disease activity and deleterious effects of the earthquake were obtained from questionnaires and hospital records. Primary outcome We evaluated the relapse rate (from inactive to active) across two consecutive months before and two consecutive months after the earthquake. In this study, we defined ‘active’ as conditions with a partial Mayo score=2 or more (UC) or a Harvey-Bradshaw index=6 or more (CD). Results Among the UC patients, disease was active in 167 patients and inactive in 379 patients before the earthquake. After the earthquake, the activity scores increased significantly (p<0.0001). A total of 86 patients relapsed (relapse rate=15.8%). The relapse rate was about twice that of the corresponding period in the previous year. Among the CD patients, 86 patients had active disease and 271 had inactive disease before the earthquake. After the earthquake, the activity indices changed little. A total of 25 patients experienced a relapse (relapse rate=7%). The relapse rate did not differ from that of the corresponding period in the previous year. Multivariate analyses revealed that UC, changes in dietary oral intake and anxiety about family finances were associated with the relapse. Conclusions Life-event stress induced by the Great East Japan Earthquake was associated with relapse in UC but not CD. PMID:23396562

Earthquake Preparedness Among Japanese Hemodialysis Patients in Prefectures Heavily Damaged by the 2011 Great East Japan Earthquake.

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Sugisawa, Hidehiro; Shimizu, Yumiko; Kumagai, Tamaki; Sugisaki, Hiroaki; Ohira, Seiji; Shinoda, Toshio

2017-08-01

The purpose of this study was to explore the factors related to earthquake preparedness in Japanese hemodialysis patients. We focused on three aspects of the related factors: health condition factors, social factors, and the experience of disasters. A mail survey of all the members of the Japan Association of Kidney Disease Patients in three Japanese prefectures (N = 4085) was conducted in March, 2013. We obtained 1841 valid responses for analysis. The health factors covered were: activities of daily living (ADL), mental distress, primary renal diseases, and the duration of dialysis. The social factors were: socioeconomic status, family structure, informational social support, and the provision of information regarding earthquake preparedness from dialysis facilities. The results show that the average percentage of participants that had met each criterion of earthquake preparedness in 2013 was 53%. Hemodialysis patients without disabled ADL, without mental distress, and requiring longer periods of dialysis, were likely to meet more of the earthquake preparedness criteria. Hemodialysis patients who had received informational social support from family or friends, had lived with spouse and children in comparison to living alone, and had obtained information regarding earthquake preparedness from dialysis facilities, were also likely to meet more of the earthquake preparedness criteria. © 2017 International Society for Apheresis, Japanese Society for Apheresis, and Japanese Society for Dialysis Therapy.

Perspective of Japanese energy policy after the Great East Japan Earthquake

International Nuclear Information System (INIS)

Kikkawa, Takeo

2012-01-01

After the Great East Japan Earthquake and following shutdown of damaged Nuclear Power Plants (NPPs) with no admittance of restart of periodically inspected NPPs, Japan was to face a great danger of shortage of power supply which led to hollowing out of Japanese industry and shifting production capacity overseas. Toward needed restart of NPPs, safety standards against severe accidents should be newly established so as to implement hazards minimization measures of NPPs, which was harmonized with the requests of Fukui prefecture having the oldest and most numerous NPPs. Author's short-term or urgent proposals were (1) safety standards should incorporate site-specific historical utmost earthquake and tsunami and be updated by reflecting latest knowledge, (2) restart of old NPPs should be put off until investigation committee concluded the relation between oldness of Fukushima Daiichi NPPs and accident progression, and (3) separation of electric power production from power distribution and transmission should be careful and not be concluded with more haste than caution. Mid-and-long-term proposals were (1) reform of nuclear power; establishment of independent nuclear regulatory authority, separation of nuclear business from private company and nationalization, and promotion of transfer of power-resources development tax to local government, (2) institutional reform of electric power; reinforcement and expansion of frequency converter and electricity interconnectors, and promotion of intense competition among electric power companies, (3) thermal power shift response; gaining bargaining power for LNG procurement and carbon dioxide reduction using bilateral offset credit mechanism through technology transfer of coal-fired thermal power; (4) expansion of renewable energy; use of geothermal, small hydro and biomass power, use of solar and wind power as distributed generation, and promotion of Smart Community activities in north Kyushu and Kamaishi. Electric power sources

[Responding to patients with home mechanical ventilation after the Great East Japan Earthquake and during the planned power outages. How should we be prepared for a future disaster ?].

Science.gov (United States)

Takechi, Yukako

2011-12-01

The unprecedented earthquake(magnitude-9 in the Japanese seismic intensity scale)hit off the east coast of Japan on March 11, 2011. Consequently, there were planned power outages in the area nearby Tokyo to avoid massive blackouts caused by a stoppage of Fukushima nuclear plants.Our clinic located in Kawasaki city was also hit by the earthquake(magnitude- 5).During the period of two months(March and April 2011), we had a total of 52 patients with home respiratory care (5-TPPV, 11-NPPV and 36-HOT)at that time.Two out of three 24 hour-TPPV users had no external battery.After the earthquake, there was a 7-hour electricity failure in some areas, and a patient with ASV(adaptive servo ventilator)was living there.Moreover, 3-hour/day power outages were carried out from March 14 to March 28, affecting people's everyday lives. However, the patient had no harmful influences from the power failure because a ventilation company lent us an external battery(4-9 hour life capacity)for the patients, and we were able to avoid an emergency situation caused by the power failure.In conclusion, we ought to be prepared for patients with home mechanical ventilation in the future toward unforeseen large scale power outages.

Modeling of periodic great earthquakes on the San Andreas fault: Effects of nonlinear crustal rheology

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Reches, Ze'ev; Schubert, Gerald; Anderson, Charles

1994-01-01

We analyze the cycle of great earthquakes along the San Andreas fault with a finite element numerical model of deformation in a crust with a nonlinear viscoelastic rheology. The viscous component of deformation has an effective viscosity that depends exponentially on the inverse absolute temperature and nonlinearity on the shear stress; the elastic deformation is linear. Crustal thickness and temperature are constrained by seismic and heat flow data for California. The models are for anti plane strain in a 25-km-thick crustal layer having a very long, vertical strike-slip fault; the crustal block extends 250 km to either side of the fault. During the earthquake cycle that lasts 160 years, a constant plate velocity v(sub p)/2 = 17.5 mm yr is applied to the base of the crust and to the vertical end of the crustal block 250 km away from the fault. The upper half of the fault is locked during the interseismic period, while its lower half slips at the constant plate velocity. The locked part of the fault is moved abruptly 2.8 m every 160 years to simulate great earthquakes. The results are sensitive to crustal rheology. Models with quartzite-like rheology display profound transient stages in the velocity, displacement, and stress fields. The predicted transient zone extends about 3-4 times the crustal thickness on each side of the fault, significantly wider than the zone of deformation in elastic models. Models with diabase-like rheology behave similarly to elastic models and exhibit no transient stages. The model predictions are compared with geodetic observations of fault-parallel velocities in northern and central California and local rates of shear strain along the San Andreas fault. The observations are best fit by models which are 10-100 times less viscous than a quartzite-like rheology. Since the lower crust in California is composed of intermediate to mafic rocks, the present result suggests that the in situ viscosity of the crustal rock is orders of magnitude

Survey of preventable disaster death at medical institutions in areas affected by the Great East Japan Earthquake: a retrospective preliminary investigation of medical institutions in Miyagi Prefecture.

Science.gov (United States)

Yamanouchi, Satoshi; Sasaki, Hiroyuki; Tsuruwa, Miho; Ueki, Yuzuru; Kohayagawa, Yoshitaka; Kondo, Hisayoshi; Otomo, Yasuhiro; Koido, Yuichi; Kushimoto, Shigeki

2015-04-01

The 2011, magnitude (M) 9, Great East Japan Earthquake and massive tsunami caused widespread devastation and left approximately 18,500 people dead or missing. The incidence of preventable disaster death (PDD) during the Great East Japan Earthquake remains to be clarified; the present study investigated PDD at medical institutions in areas affected by the Great East Japan Earthquake in order to improve disaster medical systems. A total of 25 hospitals in Miyagi Prefecture (Japan) that were disaster base hospitals (DBHs), or had at least 20 patient deaths between March 11, 2011 and April 1, 2011, were selected to participate based on the results of a previous study. A database was created using the medical records of all patient deaths (n=868), and PDD was determined from discussion with 10 disaster health care professionals. A total of 102 cases of PDD were identified at the participating hospitals. The rate of PDD was higher at coastal hospitals compared to inland hospitals (62/327, 19.0% vs 40/541, 7.4%; Pdeath at medical institutions in areas affected by the Great East Japan Earthquake occurred mainly at coastal hospitals. Insufficient resources (at GHs), environmental factors (at coastal hospitals), and delayed medical intervention (at all hospitals) constituted the major potential contributing factors. Further investigation of all medical institutions in Miyagi Prefecture, including those with fewer than 20 patient deaths, is required in order to obtain a complete picture of the details of PDD at medical institutions in the disaster area.

TECTONIC AND SEISMOLOGICAL ASPECTS OF THE GREAT JAPAN EARTHQUAKE OF MARCH 11, 2011

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Ivan N. Tikhonov

2011-01-01

Full Text Available The publication presents a review of the structure and seismotectonic features of the Pacific margin of the NorthEastern Honshu Island on the basis of data from seismic reflection and CDP, drilling and detailed seismic studies in view of the megaearthquake (Mw=9.0 which occurred in Japan on March 11, 2011. The megaearthquake is discussed in terms of its position in the succession of the strongest events (M≥7.6 in the area under study within the historical period and in the recent timeline. It is suggested that the period of recurrence is about 40 years for great events and about 1000+ years for megaearthquakes. A number of facts suggesting a probability of a planetaryscale earthquake in the Honshu Island region are revealed. Specifically, a seismic gap with a total length of about 800 km is determined in the study area. It is located southward of 39° north latitude has already manifested aftershocks of the megaearthquake of March 11, 2011. It is probable that the megaearthquake was related to the deep thrust along the Benioff zone and the Oyashio nappe being its structural cap rock in the middle Pacific slope. The sequence of its aftershocks is compared with those of the SumatraAndaman (Mw=9.3, 2004 and Simushir (Mw=8.3, 2006 earthquakes. It is established that development of the aftershock sequences of the first and second events was very similar in time, and development of the areas of aftershock epicentres of the first and third earthquakes is similar in space. The above similarities give grounds to suggest that an aftershock (M~8.0 is possible with a relative shifting from the main shock towards the deep trench.

From Multi-Sensors Observations Towards Cross-Disciplinary Study of Pre-Earthquake Signals. What have We Learned from the Tohoku Earthquake?

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Ouzounov, D.; Pulinets, S.; Papadopoulos, G.; Kunitsyn, V.; Nesterov, I.; Hayakawa, M.; Mogi, K.; Hattori, K.; Kafatos, M.; Taylor, P.

2012-01-01

The lessons we have learned from the Great Tohoku EQ (Japan, 2011) how this knowledge will affect our future observation and analysis is the main focus of this presentation.We present multi-sensors observations and multidisciplinary research in our investigation of phenomena preceding major earthquakes. These observations revealed the existence of atmospheric and ionospheric phenomena occurring prior to theM9.0 Tohoku earthquake of March 11, 2011, which indicates s new evidence of a distinct coupling between the lithosphere and atmosphere/ionosphere, as related to underlying tectonic activity. Similar results have been reported before the catastrophic events in Chile (M8.8, 2010), Italy (M6.3, 2009) and Sumatra (M9.3, 2004). For the Tohoku earthquake, our analysis shows a synergy between several independent observations characterizing the state of the lithosphere /atmosphere coupling several days before the onset of the earthquakes, namely: (i) Foreshock sequence change (rate, space and time); (ii) Outgoing Long wave Radiation (OLR) measured at the top of the atmosphere; and (iii) Anomalous variations of ionospheric parameters revealed by multi-sensors observations. We are presenting a cross-disciplinary analysis of the observed pre-earthquake anomalies and will discuss current research in the detection of these signals in Japan. We expect that our analysis will shed light on the underlying physics of pre-earthquake signals associated with some of the largest earthquake events

The HayWired Earthquake Scenario—Earthquake Hazards

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Detweiler, Shane T.; Wein, Anne M.

2017-04-24

The HayWired scenario is a hypothetical earthquake sequence that is being used to better understand hazards for the San Francisco Bay region during and after an earthquake of magnitude 7 on the Hayward Fault. The 2014 Working Group on California Earthquake Probabilities calculated that there is a 33-percent likelihood of a large (magnitude 6.7 or greater) earthquake occurring on the Hayward Fault within three decades. A large Hayward Fault earthquake will produce strong ground shaking, permanent displacement of the Earth’s surface, landslides, liquefaction (soils becoming liquid-like during shaking), and subsequent fault slip, known as afterslip, and earthquakes, known as aftershocks. The most recent large earthquake on the Hayward Fault occurred on October 21, 1868, and it ruptured the southern part of the fault. The 1868 magnitude-6.8 earthquake occurred when the San Francisco Bay region had far fewer people, buildings, and infrastructure (roads, communication lines, and utilities) than it does today, yet the strong ground shaking from the earthquake still caused significant building damage and loss of life. The next large Hayward Fault earthquake is anticipated to affect thousands of structures and disrupt the lives of millions of people. Earthquake risk in the San Francisco Bay region has been greatly reduced as a result of previous concerted efforts; for example, tens of billions of dollars of investment in strengthening infrastructure was motivated in large part by the 1989 magnitude 6.9 Loma Prieta earthquake. To build on efforts to reduce earthquake risk in the San Francisco Bay region, the HayWired earthquake scenario comprehensively examines the earthquake hazards to help provide the crucial scientific information that the San Francisco Bay region can use to prepare for the next large earthquake, The HayWired Earthquake Scenario—Earthquake Hazards volume describes the strong ground shaking modeled in the scenario and the hazardous movements of

The Role of Motivation and Creativity in Sustaining Volunteerism of Citizenship for Positive Youth Development after the Great East Japan Earthquake

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Oie, Mayumi

2017-01-01

This paper examined how the interdisciplinary field of volunteer motivation and creativity research helps improve our understanding of social issues. This research focused on the victims of the Great East Japan Earthquake, which occurred on March 11, 2011, and discussed how volunteer motivations support volunteer activities, positive youth…

Mental health and related factors after the Great East Japan earthquake and tsunami.

Directory of Open Access Journals (Sweden)

Yukari Yokoyama

Full Text Available Mental health is one of the most important issues facing disaster survivors. The purpose of this study is to determine the prevalence and correlates of mental health problems in survivors of the Great East Japan Earthquake and Tsunami at 6-11 months after the disaster. The questionnaire and notification were sent to the survivors in three municipalities in the Tohoku area of the Northern part of Honshu, Japan's largest island, between September 2011 and February 2012. Questionnaires were sent to 12,772, 11,411, and 18,648 residents in the Yamada, Otsuchi, and Rikuzentakata municipalities, respectively. Residents were asked to bring the completed questionnaires to their health check-ups. A total of 11,124 or (26.0% of them underwent health check-ups, and 10,198 were enrolled. We excluded 179 for whom a K6 score was missing and two who were both 17 years of age, which left 10,025 study participants (3,934 male and 6,091 female, mean age 61.0 years. K6 was used to measure mental health problems. The respondents were classified into moderate (5-12 of K6 and serious mental health problems (13+. A total of 42.6% of the respondents had moderate or serious mental health problems. Multivariate analysis showed that women were significantly associated with mental health problems. Other variables associated with mental health problems were: younger male, health complaints, severe economic status, relocations, and lack of a social network. An interaction effect of sex and economic status on severe mental health problems was statistically significant. Our findings suggest that mental health problems were prevalent in survivors of the Great East Japan Earthquake and Tsunami. For men and women, health complaints, severe economic status, relocations, and lack of social network may be important risk factors of poor mental health. For men, interventions focusing on economic support may be particularly useful in reducing mental health problems after the disaster.

Foreshocks and aftershocks of the Great 1857 California earthquake

Science.gov (United States)

Meltzner, A.J.; Wald, D.J.

1999-01-01

The San Andreas fault is the longest fault in California and one of the longest strike-slip faults anywhere in the world, yet we know little about many aspects of its behavior before, during, and after large earthquakes. We conducted a study to locate and to estimate magnitudes for the largest foreshocks and aftershocks of the 1857 M 7.9 Fort Tejon earthquake on the central and southern segments of the fault. We began by searching archived first-hand accounts from 1857 through 1862, by grouping felt reports temporally, and by assigning modified Mercalli intensities to each site. We then used a modified form of the grid-search algorithm of Bakum and Wentworth, derived from empirical analysis of modern earthquakes, to find the location and magnitude most consistent with the assigned intensities for each of the largest events. The result confirms a conclusion of Sieh that at least two foreshocks ('dawn' and 'sunrise') located on or near the Parkfield segment of the San Andreas fault preceded the mainshock. We estimate their magnitudes to be M ~ 6.1 and M ~ 5.6, respectively. The aftershock rate was below average but within one standard deviation of the number of aftershocks expected based on statistics of modern southern California mainshock-aftershock sequences. The aftershocks included two significant events during the first eight days of the sequence, with magnitudes M ~ 6.25 and M ~ 6.7, near the southern half of the rupture; later aftershocks included a M ~ 6 event near San Bernardino in December 1858 and a M ~ 6.3 event near the Parkfield segment in April 1860. From earthquake logs at Fort Tejon, we conclude that the aftershock sequence lasted a minimum of 3.75 years.

Why the 1964 Great Alaska Earthquake matters 50 years later

Science.gov (United States)

West, Michael E.; Haeussler, Peter J.; Ruppert, Natalia A.; Freymueller, Jeffrey T.; ,

2014-01-01

Spring was returning to Alaska on Friday 27 March 1964. A two‐week cold snap had just ended, and people were getting ready for the Easter weekend. At 5:36 p.m., an earthquake initiated 12 km beneath Prince William Sound, near the eastern end of what is now recognized as the Alaska‐Aleutian subduction zone. No one was expecting this earthquake that would radically alter the coastal landscape, influence the direction of science, and indelibly mark the growth of a burgeoning state.

Earthquake precursory events around epicenters and local active faults; the cases of two inland earthquakes in Iran

Science.gov (United States)

Valizadeh Alvan, H.; Mansor, S.; Haydari Azad, F.

2012-12-01

The possibility of earthquake prediction in the frame of several days to few minutes before its occurrence has stirred interest among researchers, recently. Scientists believe that the new theories and explanations of the mechanism of this natural phenomenon are trustable and can be the basis of future prediction efforts. During the last thirty years experimental researches resulted in some pre-earthquake events which are now recognized as confirmed warning signs (precursors) of past known earthquakes. With the advances in in-situ measurement devices and data analysis capabilities and the emergence of satellite-based data collectors, monitoring the earth's surface is now a regular work. Data providers are supplying researchers from all over the world with high quality and validated imagery and non-imagery data. Surface Latent Heat Flux (SLHF) or the amount of energy exchange in the form of water vapor between the earth's surface and atmosphere has been frequently reported as an earthquake precursor during the past years. The accumulated stress in the earth's crust during the preparation phase of earthquakes is said to be the main cause of temperature anomalies weeks to days before the main event and subsequent shakes. Chemical and physical interactions in the presence of underground water lead to higher water evaporation prior to inland earthquakes. On the other hand, the leak of Radon gas occurred as rocks break during earthquake preparation causes the formation of airborne ions and higher Air Temperature (AT) prior to main event. Although co-analysis of direct and indirect observation for precursory events is considered as a promising method for future successful earthquake prediction, without proper and thorough knowledge about the geological setting, atmospheric factors and geodynamics of the earthquake-prone regions we will not be able to identify anomalies due to seismic activity in the earth's crust. Active faulting is a key factor in identification of the

Advancing Understanding of Earthquakes by Drilling an Eroding Convergent Margin

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von Huene, R.; Vannucchi, P.; Ranero, C. R.

2010-12-01

A program of IODP with great societal relevance is sampling and instrumenting the seismogenic zone. The zone generates great earthquakes that trigger tsunamis, and submarine slides thereby endangering coastal communities containing over sixty percent of the earth’s population. To asses and mitigate this endangerment it is urgent to advance understanding of fault dynamics that allows more timely anticipation of hazardous seismicity. Seismogenesis on accreting and eroding convergent plate boundaries apparently differ because of dissimilar materials along the interplate fault. As the history of instrumentally recorded earthquakes expands the difference becomes clearer. The more homogeneous clay, silt and sand subducted at accreting margins is associated with great earthquakes (M 9) whereas the fragmented upper plate rock that can dominate subducted material along an eroding margin plate interface is associated with many tsunamigenic earthquakes (Bilek, 2010). Few areas have been identified where the seismogenic zone can be reached with scientific drilling. In IODP accreting margins are studied on the NanTroSeize drill transect off Japan where the ultimate drilling of the seismogenic interface may occur by the end of IODP. The eroding Costa Rica margin will be studied in CRISP where a drill program will begin in 2011. The Costa Rican geophysical site survey will be complete with acquisition and processing of 3D seismic data in 2011 but the entire drilling will not be accomplished in IODP. It is appropriate that the accreting margin study be accomplished soon considering the indications of a pending great earthquake that will affect a country that has devoted enormous resources to IODP. However, understanding the erosional end-member is scientifically as important to an understanding of fault mechanics. Transoceanic tsunamis affect the entire Pacific rim where most subduction zones are eroding margins. The Costa Rican subduction zone is less complex operationally and

Great earthquake potential in Oregon and Washington: An overview of recent coastal geologic studies and possible segmentation of the central Cascadia subduction zone

International Nuclear Information System (INIS)

Nelson, A.R.; Personius, S.F.

1990-01-01

Fundamental questions in earthquake hazards research in the Pacific Northwest concern the magnitude and recurrence of great earthquakes in the Cascadia subduction zone in Oregon and Washington. Geologic work of the last few years has produced convincing evidence for coseismic subsidence along the Washington and Oregon coasts. Regional subsidence recorded by estuarine deposits suggests that plate-interface earthquakes of at least M w 8 (>100-km-long ruptures) occurred during the late Holocene in northern Oregon and southern Washington. Differences in the types of coastal marsh sequences between northern and south-central Oregon, however, suggest that regional coastal subsidence does not extend south of about 45.5 degrees N along the Oregon coast. North of this latitude, the coast may intersect the seaward edge of a zone of coseismic subsidence that continues southward onshore. Alternatively, the Cascadia subduction zone is segmented near 44-45 degrees N; a segment boundary at this location would suggest that plate-interface events near M w 8 along the central CSZ would be more frequent than larger (M w 9) events. South of this boundary in the Coos Bay region, the tectonic framework developed through mapping and dating of marine and fluvial terraces indicates that many episodes of abrupt marsh burial in south-central Oregon are best interpreted as the product of deformation on local structures. Some of the local deformation could be associated with moderate earthquakes (M s <6). At most sites in south-central Oregon, however, it is still unclear whether coseismic events were responses to local faulting or folding, to regional deformation during great plate-interface earthquakes, or to both. This study has potential implications for risk assessments for light water reactors in North America

STUDIES ON SOIL LIQUEFACTION AND SETTLEMENT IN THE URAYASU DISTRICT USING EFFECTIVE STRESS ANALYSES FOR THE 2011 EAST JAPAN GREAT EARTHQUAKE

Science.gov (United States)

Fukutake, Kiyoshi; Jang, Jiho

The 2011 East Japan Great Earthquake caused soil liquefaction over a wide area. In particular, severe soil liquefaction was reported in the northern parts of the reclaimed lands around Tokyo Bay, even though the seismic intensity in this area was only about 5 on the Japan scale with low acceleration. The authors surveyed the residual settlement in the Urayasu district and then conducted effective stress analyses of areas affected and not affected by liquefaction. The analyses compared with the acceleration waves monitored with K-NET Urayasu or ground settlements surveyed. It is based on the acceleration observed on the seismic bedrocks in earthquake engineering in some other districts adjacent to Urayasu. Much of the settlement was due to the long duration of the earthquake, with further settlement resulting from the aftershock. The study shows that the affects of aftershocks need to be monitored, as well as needs for improvement of simplified liquefaction prediction methods using the factor of safety, FL.

Case study of medical evacuation before and after the Fukushima Daiichi nuclear power plant accident in the great east Japan earthquake.

Science.gov (United States)

Okumura, Tetsu; Tokuno, Shinichi

2015-01-01

In Japan, participants in the disaster-specific medical transportation system have received ongoing training since 2002, incorporating lessons learned from the Great Hanshin Earthquake. The Great East Japan Earthquake occurred on March 11, 2011, and the very first disaster-specific medical transport was performed. This article reviews in detail the central government's control and coordination of the disaster medical transportation process following the Great East Japan Earthquake and the Fukushima Daiichi Nuclear Power Plant Accident. In total, 124 patients were air transported under the coordination of the C5 team in the emergency response headquarter of the Japanese Government. C5 includes experts from the Cabinet Office, Cabinet Secretariat, Fire Defense Agency, Ministry of Health, Labour and Welfare, and Ministry of Defense. In the 20-30 km evacuation zone around the Fukushima Daiichi nuclear power plant, 509 bedridden patients were successfully evacuated without any fatalities during transportation. Many lessons have been learned in disaster-specific medical transportation. The national government, local government, police, and fire agencies have made significant progress in their mutual communication and collaboration. Fortunately, hospital evacuation from the 20-30 km area was successfully performed with the aid of local emergency physicians and Disaster Medical Assistance Teams (DMATs) who have vast experience in patient transport in the course of day-to-day activities. The emergency procedures that are required during crises are an extension of basic daily procedures that are performed by emergency medical staff and first responders, such as fire fighters, emergency medical technicians, or police officers. Medical facilities including nursing homes should have a plan for long-distance (over 100 km) evacuation, and the plan should be routinely reevaluated with full-scale exercises. In addition, hospital evacuation in disaster settings should be

The Alaska earthquake, March 27, 1964: effects on communities

Science.gov (United States)

Hansen, Wallace R.; Kachadoorian, Reuben; Coulter, Henry W.; Migliaccio, Ralph R.; Waller, Roger M.; Stanley, Kirk W.; Lemke, Richard W.; Plafker, George; Eckel, Edwin B.; Mayo, Lawrence R.

1969-01-01

This is the second in a series of six reports that the U.S. Geological Survey published on the results of a comprehensive geologic study that began, as a reconnaissance survey, within 24 hours after the March 27, 1964, Magnitude 9.2 Great Alaska Earthquake and extended, as detailed investigations, through several field seasons. The 1964 Great Alaska earthquake was the largest earthquake in the U.S. since 1700. Professional Paper 542, in 7 parts, describes the effects of the earthquake on Alaskan communities.

Characteristics of Physician Outflow from Disaster Areas following the Great East Japan Earthquake.

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Saori Kashima

Full Text Available The shortage of physicians after a major disaster is a crucial issue. We aimed to evaluate the characteristics of physicians who left affected areas following the accident at Fukushima Daiichi Nuclear Power Plant caused by the Great East Japan Earthquake on March 11, 2011.Using data from a physician census conducted in 2010 (pre-disaster and 2012 (post-disaster, we evaluated changes in the number of physicians in affected areas. We then calculated the odds ratios and 95% confidence intervals using a logistic regression model to evaluate the association between physician characteristics and outflow. We also conducted stratified analyses based on physician characteristics.The number of physicians decreased in Fukushima Prefecture (-5.3% and increased in Miyagi Prefecture (2.8%. The decrease in Fukushima and increase in Miyagi were evident even after taking the prefecture's population change into account (change in physician to population ratios: -1.9% and 3.2%, respectively. Compared with physicians who lived in areas >100 km from the nuclear power plant, physicians living 20-50 km and 50-100 km were, respectively, 3.9 times (95% confidence interval, 2.6-5.7 and 2.6 times (95% confidence interval, 1.7-3.8 more likely to migrate to distant areas. In the stratified analysis, younger physicians and those earlier in their careers had higher odds ratios for outflow than other physicians (P for interaction = 0.02 and <0.01, respectively.The risk of outflow was greater among younger and early-career physicians in areas around the power plant. Political support may be necessary to recruit and retain such physicians, who will be responsible for future community health in the disaster area.

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

Science.gov (United States)

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

2008-12-01

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

Emergency feature. Great east Japan earthquake disaster Fukushima Daiichi accident

International Nuclear Information System (INIS)

Kawata, Tomio; Tsujikura, Yonezo; Kitamura, Toshiro

2011-01-01

The Tohoku Pacific Ocean earthquake occurred in March 11, 2011. The disastrous tsunami attacked Fukushima Daiichi nuclear power plants after automatically shutdown by the earthquake and all motor operated pumps became inoperable due to station black out. Despite the strenuous efforts of operators, if caused serious accident such as loss of cooling function, hydrogen explosion and release of large amount of radioactive materials into the environment, leading to nuclear power emergency that ordered resident to evacuate or remain indoors. This emergency feature consisted of four articles. The first was the interview with the president of JAIF (Japan Atomic Industrial Forum) on how to identify the cause of the accident completely, intensify safety assurance measures and promote discussions on a role of nuclear power in the nation's entire energy policy toward the reconstruction. Others were reactor states and events sequence after the accident with trend data of radiation in the reactor site, statement of president of AESJ (Atomic Energy Society of Japan) on nuclear crisis following Tohoku Pacific Ocean earthquake our response and my experience in evacuation life. (T. Tanaka)

An asthma patient with steroid-resistant decrease in peak expiratory flow after the Great East Japan earthquake showing spontaneous recovery after 1 month.

Science.gov (United States)

Yanagimoto, Shintaro; Haida, Michiko; Suko, Matsunobu

2012-01-01

People living in Japan were affected in various ways after the Great East Japan earthquake of March 11, 2011. A 52-year-old female asthma patient not directly affected by the disaster experienced a decrease in peak expiratory flow (PEF) immediately after the earthquake. Despite increasing the inhaled and oral corticosteroid doses, her PEF did not recover. One month later, her PEF level abruptly returned to normal with minimal medications, which were previously ineffective, and the asthma-related symptoms vanished. The stabilization of her state of mind and actual social state seemed to be a part of the reason for the patient's recovery.

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

The risk communication using the special website of the society of risk analysis for the Great East Japan Earthquake

International Nuclear Information System (INIS)

Tsubokawa, Hiroaki; Nagasaka, Toshinari; Sunaga, Yohei; Lee, Taiyoung; Taguchi, Hitoshi; Usuda, Yuichiro

2011-01-01

The Society for Risk Analysis Japan built the special website that reply to the people who are concerning the risk related to the Great East Japan Earthquake occurred on March 11, 2011. Although, there were many risk communication activities between the specialists of the risk research and citizens on the website, there are some significant problems for the risk communication using the website. This report summarizes the result of our activity. (author)

Damage situation by the Great East Japan Earthquake and post-quake reconstruction project of the Tandem Accelerator Facility at the University of Tsukuba

International Nuclear Information System (INIS)

Sasa, Kimikazu

2012-01-01

The 12UD Pelletron tandem accelerator at the University of Tsukuba suffered serious damage from the Great East Japan Earthquake on 11 March 2011. On the day, the 12UD Pelletron tandem accelerator was in operation at 8 MV. The electricity supply went out during the earthquake. Fortunately, there were no causalties by the earthquake in the facility. However, all high voltage accelerating columns fell down in the accelerator tank. We decided to shut down the 12UD Pelletron tandem accelerator. At present, we have a plan to install a new middle-sized tandem accelerator instead of the broken 12UD Pelletron tandem accelerator at the 2nd target room connecting the beam line to existing facilities at the 1st target room. The construction of the new accelerator system will be completed by spring 2014. (author)

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

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

Parallel Earthquake Simulations on Large-Scale Multicore Supercomputers

KAUST Repository

Wu, Xingfu

2011-01-01

Earthquakes are one of the most destructive natural hazards on our planet Earth. Hugh earthquakes striking offshore may cause devastating tsunamis, as evidenced by the 11 March 2011 Japan (moment magnitude Mw9.0) and the 26 December 2004 Sumatra (Mw9.1) earthquakes. Earthquake prediction (in terms of the precise time, place, and magnitude of a coming earthquake) is arguably unfeasible in the foreseeable future. To mitigate seismic hazards from future earthquakes in earthquake-prone areas, such as California and Japan, scientists have been using numerical simulations to study earthquake rupture propagation along faults and seismic wave propagation in the surrounding media on ever-advancing modern computers over past several decades. In particular, ground motion simulations for past and future (possible) significant earthquakes have been performed to understand factors that affect ground shaking in populated areas, and to provide ground shaking characteristics and synthetic seismograms for emergency preparation and design of earthquake-resistant structures. These simulation results can guide the development of more rational seismic provisions for leading to safer, more efficient, and economical50pt]Please provide V. Taylor author e-mail ID. structures in earthquake-prone regions.

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

Directory of Open Access Journals (Sweden)

Lobkovsky L.

2016-11-01

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

Estimation of co-seismic stress change of the 2008 Wenchuan Ms8.0 earthquake

Energy Technology Data Exchange (ETDEWEB)

Sun Dongsheng; Wang Hongcai; Ma Yinsheng; Zhou Chunjing [Key laboratory of Neotectonic movement and Geohazard, Ministry of Land and Resources, Beijing 100081 (China) and Institute of Geomechanics, Chinese academy of Geological Sciences, Beijing 100081 (China)

2012-09-26

In-situ stress change near the fault before and after a great earthquake is a key issue in the geosciences field. In this work, based on the 2008 Great Wenchuan earthquake fault slip dislocation model, the co-seismic stress tensor change due to the Wenchuan earthquake and the distribution functions around the Longmen Shan fault are given. Our calculated results are almost consistent with the before and after great Wenchuan earthquake in-situ measuring results. The quantitative assessment results provide a reference for the study of the mechanism of earthquakes.

Measuring the size of an earthquake

Science.gov (United States)

Spence, W.; Sipkin, S.A.; Choy, G.L.

1989-01-01

Earthquakes range broadly in size. A rock-burst in an Idaho silver mine may involve the fracture of 1 meter of rock; the 1965 Rat Island earthquake in the Aleutian arc involved a 650-kilometer length of the Earth's crust. Earthquakes can be even smaller and even larger. If an earthquake is felt or causes perceptible surface damage, then its intensity of shaking can be subjectively estimated. But many large earthquakes occur in oceanic areas or at great focal depths and are either simply not felt or their felt pattern does not really indicate their true size.

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

Science.gov (United States)

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

2010-04-01

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

Needs for disaster medicine: lessons from the field of the Great East Japan Earthquake.

Science.gov (United States)

Ushizawa, Hiroto; Foxwell, Alice Ruth; Bice, Steven; Matsui, Tamano; Ueki, Yutaka; Tosaka, Naoki; Shoko, Tomohisa; Aiboshi, Junichi; Otomo, Yasuhiro

2013-01-01

The Great East Japan Earthquake, which occurred in Tohoku, Japan on 11 March 2011, was followed by a devastating tsunami and damage to nuclear power plants that resulted in radiation leakage. The medical care, equipment and communication needs of four Disaster Medical Assistance Teams (DMAT) during four missions are discussed. DMATs are medically trained mobile teams used in the acute phase of disasters. The DMATs conducted four missions in devastated areas from the day of the earthquake to day 10. The first and second missions were to triage, resuscitate and treat trauma victims in Tokyo and Miyagi, respectively. The third mission was to conduct emergency medicine and primary care in Iwate. The fourth was to assist with the evacuation and screening of inpatients with radiation exposure in Fukushima. Triage, resuscitation and trauma expertise and equipment were required in Missions 1 and 2. Emergency medicine in hospitals and primary care in first-aid stations and evacuation areas were required for Mission 3. In Mission 4, the DMAT assisted with evacuation by ambulances and buses and screened people for radiation exposure. Only land phones and transceivers were available for Missions 1 to 3 although they were ineffective for urgent purposes. These DMAT missions showed that there are new needs for DMATs in primary care, radiation screening and evacuation after the acute phase of a disaster. Alternative methods for communication infrastructure post-disaster need to be investigated with telecommunication experts.

Needs for disaster medicine: lessons from the field of the Great East Japan Earthquake

Directory of Open Access Journals (Sweden)

Tomohisa Shoko

2013-01-01

Full Text Available Problem: The Great East Japan Earthquake, which occurred in Tohoku, Japan on 11 March 2011, was followed by a devastating tsunami and damage to nuclear power plants that resulted in radiation leakage. Context: The medical care, equipment and communication needs of four Disaster Medical Assistance Teams (DMAT during four missions are discussed. DMATs are medically trained mobile teams used in the acute phase of disasters. Action: The DMATs conducted four missions in devastated areas from the day of the earthquake to day 10. The first and second missions were to triage, resuscitate and treat trauma victims in Tokyo and Miyagi, respectively. The third mission was to conduct emergency medicine and primary care in Iwate. The fourth was to assist with the evacuation and screening of inpatients with radiation exposure in Fukushima. Outcome: Triage, resuscitation and trauma expertise and equipment were required in Missions 1 and 2. Emergency medicine in hospitals and primary care in first-aid stations and evacuation areas were required for Mission 3. In Mission 4, the DMAT assisted with evacuation by ambulances and buses and screened people for radiation exposure. Only land phones and transceivers were available for Missions 1 to 3 although they were ineffective for urgent purposes. Discussion: These DMAT missions showed that there are new needs for DMATs in primary care, radiation screening and evacuation after the acute phase of a disaster. Alternative methods for communication infrastructure post-disaster need to be investigated with telecommunication experts.

Uplift and Subsidence Associated with the Great Aceh-Andaman Earthquake of 2004

Science.gov (United States)

2006-01-01

The magnitude 9.2 Indian Ocean earthquake of December 26, 2004, produced broad regions of uplift and subsidence. In order to define the lateral extent and the downdip limit of rupture, scientists from Caltech, Pasadena, Calif.; NASA's Jet Propulsion Laboratory, Pasadena, Calif.; Scripps Institution of Oceanography, La Jolla, Calif.; the U.S. Geological Survey, Pasadena, Calif.; and the Research Center for Geotechnology, Indonesian Institute of Sciences, Bandung, Indonesia; first needed to define the pivot line separating those regions. Interpretation of satellite imagery and a tidal model were one of the key tools used to do this. These pre-Sumatra earthquake (a) and post-Sumatra earthquake (b) images of North Sentinel Island in the Indian Ocean, acquired from the Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER) instrument on NASA's Terra spacecraft, show emergence of the coral reef surrounding the island following the earthquake. The tide was 30 plus or minus 14 centimeters lower in the pre-earthquake image (acquired November 21, 2000) than in the post-earthquake image (acquired February 20, 2005), requiring a minimum of 30 centimeters of uplift at this locality. Observations from an Indian Coast Guard helicopter on the northwest coast of the island suggest that the actual uplift is on the order of 1 to 2 meters at this site. In figures (c) and (d), pre-earthquake and post-earthquake ASTER images of a small island off the northwest coast of Rutland Island, 38 kilometers east of North Sentinel Island, show submergence of the coral reef surrounding the island. The tide was higher in the pre-earthquake image (acquired January 1, 2004) than in the post-earthquake image (acquired February 4, 2005), requiring subsidence at this locality. The pivot line must run between North Sentinel and Rutland islands. Note that the scale for the North Sentinel Island images differs from that for the Rutland Island images. The tidal model used for this study was

Chilean megathrust earthquake recurrence linked to frictional contrast at depth

Science.gov (United States)

Moreno, M.; Li, S.; Melnick, D.; Bedford, J. R.; Baez, J. C.; Motagh, M.; Metzger, S.; Vajedian, S.; Sippl, C.; Gutknecht, B. D.; Contreras-Reyes, E.; Deng, Z.; Tassara, A.; Oncken, O.

2018-04-01

Fundamental processes of the seismic cycle in subduction zones, including those controlling the recurrence and size of great earthquakes, are still poorly understood. Here, by studying the 2016 earthquake in southern Chile—the first large event within the rupture zone of the 1960 earthquake (moment magnitude (Mw) = 9.5)—we show that the frictional zonation of the plate interface fault at depth mechanically controls the timing of more frequent, moderate-size deep events (Mw shallow earthquakes (Mw > 8.5). We model the evolution of stress build-up for a seismogenic zone with heterogeneous friction to examine the link between the 2016 and 1960 earthquakes. Our results suggest that the deeper segments of the seismogenic megathrust are weaker and interseismically loaded by a more strongly coupled, shallower asperity. Deeper segments fail earlier ( 60 yr recurrence), producing moderate-size events that precede the failure of the shallower region, which fails in a great earthquake (recurrence >110 yr). We interpret the contrasting frictional strength and lag time between deeper and shallower earthquakes to be controlled by variations in pore fluid pressure. Our integrated analysis strengthens understanding of the mechanics and timing of great megathrust earthquakes, and therefore could aid in the seismic hazard assessment of other subduction zones.

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.

EARTHQUAKE-INDUCED DEFORMATION STRUCTURES AND RELATED TO EARTHQUAKE MAGNITUDES

Directory of Open Access Journals (Sweden)

Savaş TOPAL

2003-02-01

Full Text Available Earthquake-induced deformation structures which are called seismites may helpful to clasify the paleoseismic history of a location and to estimate the magnitudes of the potention earthquakes in the future. In this paper, seismites were investigated according to the types formed in deep and shallow lake sediments. Seismites are observed forms of sand dikes, introduced and fractured gravels and pillow structures in shallow lakes and pseudonodules, mushroom-like silts protruding laminites, mixed layers, disturbed varved lamination and loop bedding in deep lake sediments. Earthquake-induced deformation structures, by benefiting from previous studies, were ordered according to their formations and earthquake magnitudes. In this order, the lowest eartquake's record is loop bedding and the highest one is introduced and fractured gravels in lacustrine deposits.

Reviewing information support during the Great East Japan Earthquake disaster : From the perspective of a hospital library that received support

Science.gov (United States)

Terasawa, Motoko

The Great East Japan Earthquake of March 11, 2011 caused extensive damage over a widespread area. Our hospital library, which is located in the affected area, was no exception. A large collection of books was lost, and some web content was inaccessible due to damage to the network environment. This greatly hindered our efforts to continue providing post-disaster medical information services. Information support, such as free access to databases, journals, and other online content related to the disaster areas, helped us immensely during this time. We were fortunate to have the cooperation of various medical employees and library members via social networks, such as twitter, during the process of attaining this information support.

Global variations of large megathrust earthquake rupture characteristics

Science.gov (United States)

Kanamori, Hiroo

2018-01-01

Despite the surge of great earthquakes along subduction zones over the last decade and advances in observations and analysis techniques, it remains unclear whether earthquake complexity is primarily controlled by persistent fault properties or by dynamics of the failure process. We introduce the radiated energy enhancement factor (REEF), given by the ratio of an event’s directly measured radiated energy to the calculated minimum radiated energy for a source with the same seismic moment and duration, to quantify the rupture complexity. The REEF measurements for 119 large [moment magnitude (Mw) 7.0 to 9.2] megathrust earthquakes distributed globally show marked systematic regional patterns, suggesting that the rupture complexity is strongly influenced by persistent geological factors. We characterize this as the existence of smooth and rough rupture patches with varying interpatch separation, along with failure dynamics producing triggering interactions that augment the regional influences on large events. We present an improved asperity scenario incorporating both effects and categorize global subduction zones and great earthquakes based on their REEF values and slip patterns. Giant earthquakes rupturing over several hundred kilometers can occur in regions with low-REEF patches and small interpatch spacing, such as for the 1960 Chile, 1964 Alaska, and 2011 Tohoku earthquakes, or in regions with high-REEF patches and large interpatch spacing as in the case for the 2004 Sumatra and 1906 Ecuador-Colombia earthquakes. Thus, combining seismic magnitude Mw and REEF, we provide a quantitative framework to better represent the span of rupture characteristics of great earthquakes and to understand global seismicity. PMID:29750186

Fractals and Forecasting in Earthquakes and Finance

Science.gov (United States)

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

2011-12-01

It is now recognized that Benoit Mandelbrot's fractals play a critical role in describing a vast range of physical and social phenomena. Here we focus on two systems, earthquakes and finance. Since 1942, earthquakes have been characterized by the Gutenberg-Richter magnitude-frequency relation, which in more recent times is often written as a moment-frequency power law. A similar relation can be shown to hold for financial markets. Moreover, a recent New York Times article, titled "A Richter Scale for the Markets" [1] summarized the emerging viewpoint that stock market crashes can be described with similar ideas as large and great earthquakes. The idea that stock market crashes can be related in any way to earthquake phenomena has its roots in Mandelbrot's 1963 work on speculative prices in commodities markets such as cotton [2]. He pointed out that Gaussian statistics did not account for the excessive number of booms and busts that characterize such markets. Here we show that both earthquakes and financial crashes can both be described by a common Landau-Ginzburg-type free energy model, involving the presence of a classical limit of stability, or spinodal. These metastable systems are characterized by fractal statistics near the spinodal. For earthquakes, the independent ("order") parameter is the slip deficit along a fault, whereas for the financial markets, it is financial leverage in place. For financial markets, asset values play the role of a free energy. In both systems, a common set of techniques can be used to compute the probabilities of future earthquakes or crashes. In the case of financial models, the probabilities are closely related to implied volatility, an important component of Black-Scholes models for stock valuations. [2] B. Mandelbrot, The variation of certain speculative prices, J. Business, 36, 294 (1963)

Public perception of risks from nuclear power plants in Japan, before the Great East Japan Earthquake

International Nuclear Information System (INIS)

Murayama, Rumiko; Nakaune, Naoko; Kishikawa, Hiroki; Uchiyama, Iwao

2011-01-01

On this research we aim to clarify public perception of risks from nuclear power plants before the Great East Japan Earthquake. The findings of the questionnaire survey conducted in 2010 showed that 1) about 70% of the people felt that they gained benefit from nuclear power plants and these were needed for their daily life. 2) Fifty percent respondents recognized there was danger to themselves and their family members with regards to nuclear power plants. The risks of nuclear power plants to Japanese society ware estimated higher than that risk to individuals of Japanese public. 3) Perception of risks from nuclear power plants to individual Japanese tended to be slightly lower between 1999 and 2010. (author)

The way of the report in the Great East Japan Earthquake and the nuclear plant accident

International Nuclear Information System (INIS)

Inoue, Yoshiyuki

2015-01-01

Nearly four years pass from the Great East Japan Earthquake. Fukushima has a big influence of the nuclear plant accident, and more than 120,000 citizens of the prefecture are still forced to refuge. The citizens of Fukushima feel that the present conditions do not come outside a prefecture and have dissatisfaction for media. A gap occurs in what media convey and thinking that inhabitants want you to tell. One of the causes is a news value point of reference. The other is that the news is carried out in a viewpoint of Tokyo. Is there not the cancellation method? I consider it from the viewpoint of a reporter living in Fukushima city. (author)

History of the great Kanto earthquakes inferred from the ages of Holocene marine terraces revealed by a comprehensive drilling survey

Science.gov (United States)

Komori, Junki; Shishikura, Masanobu; Ando, Ryosuke; Yokoyama, Yusuke; Miyairi, Yosuke

2017-08-01

We measured the emergence ages of four marine terraces in the Chikura lowland, which lies to the southeast of the Boso Peninsula, in eastern Japan, to reevaluate the history of the great earthquake occurrences along the Sagami Trough over the past 10,000 years. The dates of the marine terraces are measured via radiocarbon dating of shell fossils obtained from the marine deposits. The sampling method employed in this study collects core samples using a dense and systematic drilling survey, which increased the reliability when correlating shell fossils with marine terraces. In addition, radiocarbon dating was performed with accelerator mass spectrometry, which produces more highly accurate measurements than those measured in previous studies. Moreover, we explored the surface profiles of the terraces with detailed digital elevation model (DEM) data obtained using LiDAR. The maximum emergence ages of the marine terraces were dated at 6300 cal yBP, 3000 cal yBP, and 2200 cal yBP from the top terrace excepting the lowest terrace (which was estimated at AD1703). In addition, another previously unrecognized terrace was detected between the highest and the second terrace in both the dating and the geomorphological analyses and was dated at 5800 cal yBP. The newly obtained ages are nearly a thousand of years younger than previously estimated ages; consequently, the intervals of the great earthquakes that occurred along the Sagami Trough are estimated to be much shorter and more varied than those of previous estimations. This result revises the data used in the current assessment of the probabilities of earthquakes along the Sagami Trough, which could devastate the Tokyo metropolitan area. Furthermore, it demonstrates that the current approach could be a powerful tool to increase the accuracy of assessments of the other areas with depositional marine terraces.

Evaluating a kinematic method for generating broadband ground motions for great subduction zone earthquakes: Application to the 2003 Mw 8.3 Tokachi‐Oki earthquake

Science.gov (United States)

Wirth, Erin A.; Frankel, Arthur; Vidale, John E.

2017-01-01

We compare broadband synthetic seismograms with recordings of the 2003 Mw">MwMw 8.3 Tokachi‐Oki earthquake to evaluate a compound rupture model, in which slip on the fault consists of multiple high‐stress‐drop asperities superimposed on a background slip distribution with longer rise times. Low‐frequency synthetics (frequency (>1  Hz">>1  Hz>1  Hz) stochastic synthetics using a matched filter at 1 Hz. We show that this compound rupture model and overall approach accurately reproduces waveform envelopes and observed response spectral accelerations (SAs) from the Tokachi‐Oki event. We find that sufficiently short subfault rise times (i.e., ∼1  Hz∼1  Hz. This is achieved by either (1) including distinct subevents with short rise times, as may be suggested by the Tokachi‐Oki data, or (2) imposing a fast‐slip velocity over the entire rupture area. We also include a systematic study on the effects of varying several kinematic rupture parameters. We find that simulated strong ground motions are sensitive to the average rupture velocity and coherence of the rupture front, with more coherent ruptures yielding higher response SAs. We also assess the effects of varying the average slip velocity and the character (i.e., area, magnitude, and location) of high‐stress‐drop subevents. Even in the absence of precise constraints on these kinematic rupture parameters, our simulations still reproduce major features in the Tokachi‐Oki earthquake data, supporting its accuracy in modeling future large earthquakes.

Large earthquake rates from geologic, geodetic, and seismological perspectives

Science.gov (United States)

Jackson, D. D.

2017-12-01

Earthquake rate and recurrence information comes primarily from geology, geodesy, and seismology. Geology gives the longest temporal perspective, but it reveals only surface deformation, relatable to earthquakes only with many assumptions. Geodesy is also limited to surface observations, but it detects evidence of the processes leading to earthquakes, again subject to important assumptions. Seismology reveals actual earthquakes, but its history is too short to capture important properties of very large ones. Unfortunately, the ranges of these observation types barely overlap, so that integrating them into a consistent picture adequate to infer future prospects requires a great deal of trust. Perhaps the most important boundary is the temporal one at the beginning of the instrumental seismic era, about a century ago. We have virtually no seismological or geodetic information on large earthquakes before then, and little geological information after. Virtually all-modern forecasts of large earthquakes assume some form of equivalence between tectonic- and seismic moment rates as functions of location, time, and magnitude threshold. That assumption links geology, geodesy, and seismology, but it invokes a host of other assumptions and incurs very significant uncertainties. Questions include temporal behavior of seismic and tectonic moment rates; shape of the earthquake magnitude distribution; upper magnitude limit; scaling between rupture length, width, and displacement; depth dependence of stress coupling; value of crustal rigidity; and relation between faults at depth and their surface fault traces, to name just a few. In this report I'll estimate the quantitative implications for estimating large earthquake rate. Global studies like the GEAR1 project suggest that surface deformation from geology and geodesy best show the geography of very large, rare earthquakes in the long term, while seismological observations of small earthquakes best forecasts moderate earthquakes

Damage of the Unit 1 reactor building overhead bridge crane at Onagawa Nuclear Power Station caused by the Great East Japan Earthquake and its repair works

International Nuclear Information System (INIS)

Sugamata, Norihiko

2014-01-01

The driving shaft bearings of the Unit 1 overhead bridge crane were damaged by the Great East Japan Earthquake at Onagawa Nuclear Power Station. The situation, investigation and repair works of the bearing failure are introduced in this paper. (author)

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

International Nuclear Information System (INIS)

Inoue, Chihiro; Joe, Seongjin

2014-01-01

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

The HayWired Earthquake Scenario

Science.gov (United States)

Detweiler, Shane T.; Wein, Anne M.

2017-04-24

ForewordThe 1906 Great San Francisco earthquake (magnitude 7.8) and the 1989 Loma Prieta earthquake (magnitude 6.9) each motivated residents of the San Francisco Bay region to build countermeasures to earthquakes into the fabric of the region. Since Loma Prieta, bay-region communities, governments, and utilities have invested tens of billions of dollars in seismic upgrades and retrofits and replacements of older buildings and infrastructure. Innovation and state-of-the-art engineering, informed by science, including novel seismic-hazard assessments, have been applied to the challenge of increasing seismic resilience throughout the bay region. However, as long as people live and work in seismically vulnerable buildings or rely on seismically vulnerable transportation and utilities, more work remains to be done.With that in mind, the U.S. Geological Survey (USGS) and its partners developed the HayWired scenario as a tool to enable further actions that can change the outcome when the next major earthquake strikes. By illuminating the likely impacts to the present-day built environment, well-constructed scenarios can and have spurred officials and citizens to take steps that change the outcomes the scenario describes, whether used to guide more realistic response and recovery exercises or to launch mitigation measures that will reduce future risk.The HayWired scenario is the latest in a series of like-minded efforts to bring a special focus onto the impacts that could occur when the Hayward Fault again ruptures through the east side of the San Francisco Bay region as it last did in 1868. Cities in the east bay along the Richmond, Oakland, and Fremont corridor would be hit hardest by earthquake ground shaking, surface fault rupture, aftershocks, and fault afterslip, but the impacts would reach throughout the bay region and far beyond. The HayWired scenario name reflects our increased reliance on the Internet and telecommunications and also alludes to the

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

Comparison of cardiovascular mortality in the Great East Japan and the Great Hanshin-Awaji Earthquakes　- a large-scale data analysis of death certificates.

Science.gov (United States)

Takegami, Misa; Miyamoto, Yoshihiro; Yasuda, Satoshi; Nakai, Michikazu; Nishimura, Kunihiro; Ogawa, Hisao; Hirata, Ken-Ichi; Toh, Ryuji; Morino, Yoshihiro; Nakamura, Motoyuki; Takeishi, Yasuchika; Shimokawa, Hiroaki; Naito, Hiroaki

2015-01-01

Large earthquakes have been associated with cardiovascular disease (CVD) mortality. In Japan, the 1995 Great Hanshin-Awaji (H-A) Earthquake was an urban-underground-type earthquake, whereas the 2011 Great East Japan (GEJ) Earthquake was an ocean-trench type. In the present study, we examined how these different earthquake types affected CVD mortality. We examined death certificate data from 2008 to 2012 for 131 municipalities in Iwate, Miyagi, and Fukushima prefectures (n=320,348) and from 1992 to 1996 for 220 municipalities in Hyogo, Osaka, and Kyoto prefectures (n=592,670). A Poisson regression model showed significant increases in the monthly numbers of acute myocardial infarction (AMI)-related deaths (incident rate ratio [IRR] GEJ=1.34, P=0.001; IRR of H-A=1.57, Pdeaths (IRR of GEJ=1.42, Pdeaths remained significant only for H-A (IRR=1.13, P=0.029). When analyzing the standardized mortality ratio (SMR) after the earthquakes using the Cochran-Armitage trend test, seismic intensity was significantly associated with AMI mortality for 2 weeks after both the GEJ (P for trend=0.089) and H-A earthquakes (P for trend=0.005). Following the GEJ and H-A earthquakes, there was a sharp increase in CVD mortality. The effect of the disaster was sustained for months after the H-A earthquake, but was diminished after the GEJ Earthquake.

The Alaska earthquake, March 27, 1964: effects on hydrologic regimen

Science.gov (United States)

Waller, Roger M.; Coble, R.W.; Post, Austin; McGarr, Arthur; Vorhis, Robert C.

1966-01-01

This is the fourth in a series of six reports that the U.S. Geological Survey published on the results of a comprehensive geologic study that began, as a reconnaissance survey, within 24 hours after the March 27, 1964, Magnitude 9.2 Great Alaska Earthquake and extended, as detailed investigations, through several field seasons. The 1964 Great Alaska earthquake was the largest earthquake in the U.S. since 1700. Professional Paper 544, in 5 parts, describes the effects on hydrologic regimen.

Medical relief activities conducted by Nippon Medical School in the acute phase of the Great East Japan Earthquake 2011.

Science.gov (United States)

Fuse, Akira; Shuto, Yuki; Ando, Fumihiko; Shibata, Masafumi; Watanabe, Akihiro; Onda, Hidetaka; Masuno, Tomohiko; Yokota, Hiroyuki

2011-01-01

At 14:46 on March 11, 2011, the Great East Japan Earthquake and tsunami occurred off the coast of Honshu, Japan. In the acute phase of this catastrophe, one of our teams was deployed as a Tokyo Disaster Medical Assistance Team (DMAT) to Kudan Kaikan in Tokyo, where the ceiling of a large hall had partially collapsed as the result of the earthquake, to conduct triage at the scene: 6 casualties were assigned to the red category (immediate), which included 1 case of cardiopulmonary arrest and 1 of flail chest; 8 casualties in the yellow category (delayed); and 22 casualties in the green category (minor). One severely injured person was transported to our hospital. Separately, our medical team was deployed to Miyagi 2 hours after the earthquake in our multipurpose medical vehicle as part of Japan DMAT (J-DMAT). We were the first DMAT from the metropolitan area to arrive, but we were unable to start medical relief activities because the information infrastructure had been destroyed and no specific information had yet reached the local headquarters. Early next morning, J-DMAT decided to support Sendai Medical Center and search and rescue efforts in the affected area and to establish a staging care unit at Camp Kasuminome of the Japan Self-Defense Force. Our team joined others to establish the staging care unit. Because information was still confused until day 3 of the disaster and we could not adequately grasp onsite medical needs, our J-DMAT decided to provide onsite support at Ishinomaki Red Cross Hospital, a disaster base hospital, and relay information about its needs to the local J-DMAT headquarters. Although our medical relief teams were deployed as quickly as possible, we could not begin medical relief activities immediately owing to the severely damaged information infrastructure. Only satellite mobile phones could be operated, and information on the number of casualties and the severity of shortages of lifeline services could be obtained only through a "go and

Guidelines for earthquake ground motion definition for the Eastern United States

International Nuclear Information System (INIS)

Gwaltney, R.C.; Aramayo, G.A.; Williams, R.T.

1985-01-01

Guidelines for the determination of earthquake ground-motion definition for the eastern United States are established in this paper. Both far-field and near-field guidelines are given. The guidelines were based on an extensive review of the current procedures for specifying ground motion in the United States. Both empirical and theoretical procedures were used in establishing the guidelines because of the low seismicity in the eastern United States. Only a few large to great (M > 7.5) sized earthquakes have occurred in this region, no evidence of tectonic surface ruptures related to historic or Holocene earthquakes have been found, and no currently active plate boundaries of any kind are known in this region. Very little instrumented data has been gathered in the East. Theoretical procedures are proposed so that in regions of almost no data a reasonable level of seismic ground motion activity can be assumed. The guidelines are to be used to develop the Safe Shutdown Earthquake, SSE. A new procedure for establishing the Operating Basis Earthquake, OBE, is proposed, in particular for the eastern United States. The OBE would be developed using a probabilistic assessment of the geological conditions and the recurrence of seismic events at a site. These guidelines should be useful in development of seismic design requirements for future reactors

Southern Peru desert shattered by the great 2001 earthquake: Implications for paleoseismic and paleo-El Niño–Southern Oscillation records

OpenAIRE

Keefer, David K.; Moseley, Michael E.

2004-01-01

In the desert region around the coastal city of Ilo, the great southern Peru earthquake of June 23, 2001 (8.2–8.4 moment magnitude), produced intense and widespread ground-failure effects. These effects included abundant landslides, pervasive ground cracking, microfracturing of surficial hillslope materials, collapse of drainage banks over long stretches, widening of hillside rills, and lengthening of first-order tributary channels. We have coined the term “shattered landscape” to describe th...

Earthquake prediction by Kina Method

International Nuclear Information System (INIS)

Kianoosh, H.; Keypour, H.; Naderzadeh, A.; Motlagh, H.F.

2005-01-01

Earthquake prediction has been one of the earliest desires of the man. Scientists have worked hard to predict earthquakes for a long time. The results of these efforts can generally be divided into two methods of prediction: 1) Statistical Method, and 2) Empirical Method. In the first method, earthquakes are predicted using statistics and probabilities, while the second method utilizes variety of precursors for earthquake prediction. The latter method is time consuming and more costly. However, the result of neither method has fully satisfied the man up to now. In this paper a new method entitled 'Kiana Method' is introduced for earthquake prediction. This method offers more accurate results yet lower cost comparing to other conventional methods. In Kiana method the electrical and magnetic precursors are measured in an area. Then, the time and the magnitude of an earthquake in the future is calculated using electrical, and in particular, electrical capacitors formulas. In this method, by daily measurement of electrical resistance in an area we make clear that the area is capable of earthquake occurrence in the future or not. If the result shows a positive sign, then the occurrence time and the magnitude can be estimated by the measured quantities. This paper explains the procedure and details of this prediction method. (authors)

THE RESPONSE OF MONTEREY BAY TO THE GREAT TOHOKU EARTHQUAKE OF 2011

Directory of Open Access Journals (Sweden)

D. Carroll

2011-01-01

Full Text Available The response of Monterey Bay to the Great Tohoku earthquake of 2011 is examined in this study. From a practical standpoint, although the resulting tsunami did not cause any damage to the open harbors at Monterey and Moss Landing, it caused extensive damage to boats and infrastructure in Santa Cruz Harbor, which is closed to surrounding waters. From a scientific standpoint, the observed and predicted amplitudes of the tsunami at 1 km from the source were 21.3 and 22.5 m based on the primary arrival from one DART bottom pressure recorder located 986 km ENE of the epicenter. The predicted and observed travel times for the tsunami to reach Monterey Bay agreed within 3%. The predicted and observed periods of the tsunami-generated wave before it entered the bay yielded periods that approached 2 hours. Once the tsunami entered Monterey Bay it was transformed into a seiche with a primary period of 36-37 minutes, corresponding to quarter-wave resonance within the bay. Finally, from a predictive standpoint, major tsunamis that enter the bay from the northwest, as in the present case, are the ones most likely to cause damage to Santa Cruz harbor.

Southern Peru desert shattered by the great 2001 earthquake: implications for paleoseismic and paleo-El Nino-Southern Oscillation records.

Science.gov (United States)

Keefer, David K; Moseley, Michael E

2004-07-27

In the desert region around the coastal city of Ilo, the great southern Peru earthquake of June 23, 2001 (8.2-8.4 moment magnitude), produced intense and widespread ground-failure effects. These effects included abundant landslides, pervasive ground cracking, microfracturing of surficial hillslope materials, collapse of drainage banks over long stretches, widening of hillside rills, and lengthening of first-order tributary channels. We have coined the term "shattered landscape" to describe the severity of these effects. Long-term consequences of this landscape shattering are inferred to include increased runoff and sediment transport during postearthquake rainstorms. This inference was confirmed during the first minor postearthquake rainstorm there, which occurred in June and July of 2002. Greater amounts of rainfall in this desert region have historically been associated with El Niño events. Previous studies of an unusual paleoflood deposit in this region have concluded that it is the product of El Niño-generated precipitation falling on seismically disturbed landscapes. The effects of the 2001 earthquake and 2002 rainstorm support that conclusion.

Dynamic Source Parameters of the 2008 Wenchuan 8.0, China, Earthquake

Science.gov (United States)

Yu, X.; Zhang, W.

2013-12-01

On May 12, 2008, a huge earthquake with magnitude Ms 8.0 occurred in the Wenchuan, Sichuan Province of China. This event was the most devastating earthquake in the mainland of China since the Great 1976 M7.8 Tangshan earthquake. It resulted in tremendous losses of life and property. Due to occur in the mountainous area, this great earthquake and the following thousands aftershocks also caused many other geological disasters, such as landslide, mud-rock flow and "quake lakes" which formed by landslide-induced reservoirs. This earthquake occurred along the Longmenshan fault, as the result of motion on a northeast striking reverse fault or thrust fault on the northwestern margin of the Sichuan Basin. The earthquake's epicenter and focal-mechanism are consistent with it having occurred as the result of movement on the Longmenshan fault or a tectonically related fault. The earthquake reflects tectonic stresses resulting from the convergence of crustal material slowly moving from the high Tibetan Plateau, to the west, against strong crust underlying the Sichuan Basin and southeastern China. In this study, the spatial and temporal distribution of the stress on the fault plane of this great earthquake is estimated from the inversion results (Qin & Zhang, 2013) by solving the elastodynamic equations. Then, the dynamic source parameters are determined and the relations between the shear stress and the slip, the shear stress and the slip-rate for all grid positions on the fault are investigated. Finally, the frictional law for the source rupture is inferred from the dynamic source parameters. Based on the obtained dynamic source parameters, we try to rebuild the dynamic rupture process of this event and discuss the characteristics of this great earthquake.

Charles Darwin's earthquake reports

Science.gov (United States)

Galiev, Shamil

2010-05-01

As it is the 200th anniversary of Darwin's birth, 2009 has also been marked as 170 years since the publication of his book Journal of Researches. During the voyage Darwin landed at Valdivia and Concepcion, Chile, just before, during, and after a great earthquake, which demolished hundreds of buildings, killing and injuring many people. Land was waved, lifted, and cracked, volcanoes awoke and giant ocean waves attacked the coast. Darwin was the first geologist to observe and describe the effects of the great earthquake during and immediately after. These effects sometimes repeated during severe earthquakes; but great earthquakes, like Chile 1835, and giant earthquakes, like Chile 1960, are rare and remain completely unpredictable. This is one of the few areas of science, where experts remain largely in the dark. Darwin suggested that the effects were a result of ‘ …the rending of strata, at a point not very deep below the surface of the earth…' and ‘…when the crust yields to the tension, caused by its gradual elevation, there is a jar at the moment of rupture, and a greater movement...'. Darwin formulated big ideas about the earth evolution and its dynamics. These ideas set the tone for the tectonic plate theory to come. However, the plate tectonics does not completely explain why earthquakes occur within plates. Darwin emphasised that there are different kinds of earthquakes ‘...I confine the foregoing observations to the earthquakes on the coast of South America, or to similar ones, which seem generally to have been accompanied by elevation of the land. But, as we know that subsidence has gone on in other quarters of the world, fissures must there have been formed, and therefore earthquakes...' (we cite the Darwin's sentences following researchspace. auckland. ac. nz/handle/2292/4474). These thoughts agree with results of the last publications (see Nature 461, 870-872; 636-639 and 462, 42-43; 87-89). About 200 years ago Darwin gave oneself airs by the

Ethical challenges for the design and conduct of mega-biobanking from Great East Japan Earthquake victims.

Science.gov (United States)

Matsui, Kenji; Tashiro, Shimon

2014-07-04

Amid continuing social unrest from the Great East Japan Earthquake and subsequent Fukushima nuclear accident of 2011, the Japanese government announced plans for a major biobanking project in the disaster-stricken areas, to be administered by the 'Tohoku Medical Megabank Organization' (ToMMo). This project differs from previous biobanking projects in that it 1) was initiated mainly to boost post-disaster recovery and reconstruction; and 2) targets the area's survivors as its primary subjects. Here, we review the ethics of the ToMMo biobanking project within the wider context of disaster remediation. Private citizens in the Tohoku region have criticized the project proposal, asking for further review of the ethics of targeting disaster survivors for this study. They claim the project violates the Declaration of Helsinki's ethical provisions in that (1) government and university researchers initiated it without consulting any Tohoku survivors; (2) survivors already suffering extreme losses may view study involvement as meaningless or even undesirable, yet feel forced to participate in exchange for tenuous promises of future assistance, thus exploiting those most in need.Although the ToMMo has promised certain future social benefits for the target population in exchange for participating in its biobanking research, it is questionable whether such research can address the immediate health needs of the Tohoku disaster survivors in any significant fashion. The ethics of recruiting still-struggling survivors is also questionable. This case analysis demonstrates that conducting a post-disaster biobanking project on survivors poses issues concerning potential exploitation and the just distribution of benefits and burdens. Though the ToMMo emphasizes the project's importance for individual survivors and regional recovery, it is questionable whether such research can justly respond to the survivors' immediate health needs and whether truly voluntary participation can be

APPLICATION OF MOBILE LIDAR MAPPING FOR DAMAGE SURVEY AFTER GREAT EAST JAPAN EARTHQUAKE

Directory of Open Access Journals (Sweden)

E. Ariyasu

2012-07-01

Full Text Available A massive earthquake of magnitude 9.0 hit off Tohoku region, the east coast of the Japanese main land, on 11 March, 2011. It was one of the historically powerful earthquakes in the world. The earthquake triggered powerful tsunami and broad-scale subsidence, so that, residential areas and infrastructures were catastrophically damaged. After that, it is necessary to renew a new map for reconstruction, such as cadastral map. In the critical situation, Mobile LiDAR Mapping system is efficient to rapidly collect fine data at once and capture more details of terrain features than data from airborne. In this paper, we would like to introduce procured instruments in our company and implemented survey several areas after the event, and suggest how to survey for cadastral map by Mobile LiDAR Mapping System.

A study on the factors that contribute to the practice of organizational behavior as coping with unexpected events. Exploration of the factors through the case survey of the Great East Japan Earthquake

International Nuclear Information System (INIS)

Hayase, Kenichi

2016-01-01

In the organizations in the face of unexpected events in the 2011 Great East Japan Earthquake, the organizational behavior which was coped with by their members was seen. It is important to prepare emergency that the backgrounds of those organizational behavior were understood. This study aimed to explore the factors that contribute to the practice of organizational behavior as coping with unexpected events through the case survey of the Great East Japan Earthquake. This study carried out literature survey and interview survey of personnel in charge of disaster prevention, BCP in the 10 organizations which coped with the earthquake. As the result, the following two outcomes were obtained. 1) Factors that contribute to the practice of the 13 kinds of the organizational behavior were clarified. 2) Discussion from the view point of the factors classification indicated the importance of the factors which are classified into normal business and features of organization. (author)

Investigating landslides caused by earthquakes - A historical review

Science.gov (United States)

Keefer, D.K.

2002-01-01

Post-earthquake field investigations of landslide occurrence have provided a basis for understanding, evaluating, and mapping the hazard and risk associated with earthquake-induced landslides. This paper traces the historical development of knowledge derived from these investigations. Before 1783, historical accounts of the occurrence of landslides in earthquake are typically so incomplete and vague that conclusions based on these accounts are of limited usefulness. For example, the number of landslides triggered by a given event is almost always greatly underestimated. The first formal, scientific post-earthquake investigation that included systematic documentation of the landslides was undertaken in the Calabria region of Italy after the 1783 earthquake swarm. From then until the mid-twentieth century, the best information on earthquake-induced landslides came from a succession of post-earthquake investigations largely carried out by formal commissions that undertook extensive ground-based field studies. Beginning in the mid-twentieth century, when the use of aerial photography became widespread, comprehensive inventories of landslide occurrence have been made for several earthquakes in the United States, Peru, Guatemala, Italy, El Salvador, Japan, and Taiwan. Techniques have also been developed for performing "retrospective" analyses years or decades after an earthquake that attempt to reconstruct the distribution of landslides triggered by the event. The additional use of Geographic Information System (GIS) processing and digital mapping since about 1989 has greatly facilitated the level of analysis that can applied to mapped distributions of landslides. Beginning in 1984, synthesis of worldwide and national data on earthquake-induced landslides have defined their general characteristics and relations between their occurrence and various geologic and seismic parameters. However, the number of comprehensive post-earthquake studies of landslides is still

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

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.

Guidelines for earthquake ground motion definition for the eastern United States

International Nuclear Information System (INIS)

Gwaltney, R.C.; Aramayo, G.A.; Williams, R.T.

1985-01-01

Guidelines for the determination of earthquake ground-motion definition for the eastern United States are established in this paper. Both far-field and near-field guidelines are given. The guidelines were based on an extensive review of the current procedures for specifying ground motion in the United States. Both empirical and theoretical procedures were used in establishing the guidelines because of the low seismicity in the eastern United States. Only a few large to great (M > 7.5) sized earthquakes have occurred in this region, no evidence of tectonic surface ruptures related to historic or Holocene earthquakes have been found, and no currently active plate boundaries of any kind are known in this region. Very little instrumented data has been gathered in the East. Theoretical procedures are proposed so that in regions of almost no data a reasonable level of seismic ground motion activity can be assumed. The guidelines are to be used to develop the Safe Shutdown Earthquake, SSE. A new procedure for establishing the Operating Basis Earthquake, OBE, is proposed, in particular for the eastern United States. The OBE would be developed using a probabilistic assessment of the geological conditions and the recurrence of seismic events at a site. These guidelines should be useful in development of seismic design requirements for future reactors. 17 refs., 2 figs., 1 tab

Comparison of two large earthquakes: the 2008 Sichuan Earthquake and the 2011 East Japan Earthquake.

Science.gov (United States)

Otani, Yuki; Ando, Takayuki; Atobe, Kaori; Haiden, Akina; Kao, Sheng-Yuan; Saito, Kohei; Shimanuki, Marie; Yoshimoto, Norifumi; Fukunaga, Koichi

2012-01-01

Between August 15th and 19th, 2011, eight 5th-year medical students from the Keio University School of Medicine had the opportunity to visit the Peking University School of Medicine and hold a discussion session titled "What is the most effective way to educate people for survival in an acute disaster situation (before the mental health care stage)?" During the session, we discussed the following six points: basic information regarding the Sichuan Earthquake and the East Japan Earthquake, differences in preparedness for earthquakes, government actions, acceptance of medical rescue teams, earthquake-induced secondary effects, and media restrictions. Although comparison of the two earthquakes was not simple, we concluded that three major points should be emphasized to facilitate the most effective course of disaster planning and action. First, all relevant agencies should formulate emergency plans and should supply information regarding the emergency to the general public and health professionals on a normal basis. Second, each citizen should be educated and trained in how to minimize the risks from earthquake-induced secondary effects. Finally, the central government should establish a single headquarters responsible for command, control, and coordination during a natural disaster emergency and should centralize all powers in this single authority. We hope this discussion may be of some use in future natural disasters in China, Japan, and worldwide.

VOLUNTARY ACTIVITIES AND ONLINE EDUCATION FOR DIGITAL HERITAGE INVENTORY DEVELOPMENT AFTER THE GREAT EAST JAPAN EARTHQUAKE

Directory of Open Access Journals (Sweden)

Y. Kondo

2013-07-01

Full Text Available Consortium for Earthquake-Damaged Cultural Heritage (CEDACH is a voluntary initiative launched just after the Great East Japan Earthquake on 11 March 2011. The consortium is developing a social network between local cultural resource managers restoring disaster-damaged cultural heritage on one side and remote researchers including historians, archaeologists and specialists of cultural information studies on the other side, in order to facilitate collaborative projects. This paper presents three projects in which CEDACH contributed to the development of a digital inventory for disaster-damaged heritage management through web-based collaborations by self-motivated workers. The first project, CEDACH GIS, developed an online archaeological site inventory for the disaster area. Although a number of individuals voluntarily participated in the project at the beginning, it gradually stagnated due to limited need for local rescue archaeology. However, the experience of online-based collaborations worked well for the second project proposed by local specialists, in which CEDACH restored the book catalogue of a tsunami-devastated research library. This experience highlighted the need for online education to improve information and communication technologies (ICT skills of data builders. Therefore, in the third project called CEDACHeLi, an e-Learning management system was developed to facilitate learning the fundamental knowledge and techniques required for information processing in rescue operations of disaster-damaged cultural heritage. This system will contribute to improved skills and motivation of potential workers for further developments in digital heritage inventory.

Voluntary Activities and Online Education for Digital Heritage Inventory Development after the Great East Japan Earthquake

Science.gov (United States)

Kondo, Y.; Uozu, T.; Seino, Y.; Ako, T.; Goda, Y.; Fujimoto, Y.; Yamaguchi, H.

2013-07-01

Consortium for Earthquake-Damaged Cultural Heritage (CEDACH) is a voluntary initiative launched just after the Great East Japan Earthquake on 11 March 2011. The consortium is developing a social network between local cultural resource managers restoring disaster-damaged cultural heritage on one side and remote researchers including historians, archaeologists and specialists of cultural information studies on the other side, in order to facilitate collaborative projects. This paper presents three projects in which CEDACH contributed to the development of a digital inventory for disaster-damaged heritage management through web-based collaborations by self-motivated workers. The first project, CEDACH GIS, developed an online archaeological site inventory for the disaster area. Although a number of individuals voluntarily participated in the project at the beginning, it gradually stagnated due to limited need for local rescue archaeology. However, the experience of online-based collaborations worked well for the second project proposed by local specialists, in which CEDACH restored the book catalogue of a tsunami-devastated research library. This experience highlighted the need for online education to improve information and communication technologies (ICT) skills of data builders. Therefore, in the third project called CEDACHeLi, an e-Learning management system was developed to facilitate learning the fundamental knowledge and techniques required for information processing in rescue operations of disaster-damaged cultural heritage. This system will contribute to improved skills and motivation of potential workers for further developments in digital heritage inventory.

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

Science.gov (United States)

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

2016-04-01

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

Investigating Landslides Caused by Earthquakes A Historical Review

Science.gov (United States)

Keefer, David K.

Post-earthquake field investigations of landslide occurrence have provided a basis for understanding, evaluating, and mapping the hazard and risk associated withearthquake-induced landslides. This paper traces thehistorical development of knowledge derived from these investigations. Before 1783, historical accounts of the occurrence of landslides in earthquakes are typically so incomplete and vague that conclusions based on these accounts are of limited usefulness. For example, the number of landslides triggered by a given event is almost always greatly underestimated. The first formal, scientific post-earthquake investigation that included systematic documentation of the landslides was undertaken in the Calabria region of Italy after the 1783 earthquake swarm. From then until the mid-twentieth century, the best information on earthquake-induced landslides came from a succession ofpost-earthquake investigations largely carried out by formal commissions that undertook extensive ground-based field studies. Beginning in the mid-twentieth century, when the use of aerial photography became widespread, comprehensive inventories of landslide occurrence have been made for several earthquakes in the United States, Peru, Guatemala, Italy, El Salvador, Japan, and Taiwan. Techniques have also been developed for performing ``retrospective'' analyses years or decades after an earthquake that attempt to reconstruct the distribution of landslides triggered by the event. The additional use of Geographic Information System (GIS) processing and digital mapping since about 1989 has greatly facilitated the level of analysis that can applied to mapped distributions of landslides. Beginning in 1984, syntheses of worldwide and national data on earthquake-induced landslides have defined their general characteristics and relations between their occurrence and various geologic and seismic parameters. However, the number of comprehensive post-earthquake studies of landslides is still

Potential future impacts of climatic change on the Great Plains

International Nuclear Information System (INIS)

Smit, B.

1991-01-01

A synopsis is provided of approaches to impact studies in the Great Plains, findings from studies of future impacts are summarized, and opportunities for enhancing understanding of future impacts are discussed. Potential impacts of climate change on agriculture, water resources, forestry, recreation/tourism, and energy are summarized. Impact analyses need to look more rigorously at variability in climate, the probabilities of various climatic conditions, and the sensitivity of social and economic activities to climatic variability. Most economic impact studies have assumed no adaptive behavior on the part of economic decision makers. Credible impact assessments require an improved understanding of the sensitivity and adaptability of sectors to climatic conditions, particularly variability. The energy sector in the Great Plains region is likely to be more sensitive to political developments in the Middle East than to climatic variability and change. Speculation and analysis of climate impacts have focused on supply conditions and demands, yet the sector is more keenly sensitive to policy implications of climatic change, such as the potential for fossil fuel taxes or other legislative or pricing constraints. 28 refs

Study of street-blockades caused by a large earthquake; Daishinsaiji ni okeru doro heisoku ni knsuru kenkyu (Hanshin Awaji daishinsai ni okeru jittai bunseki)

Energy Technology Data Exchange (ETDEWEB)

Imaizumi, K. [Kajima Corp., Tokyo (Japan); Asami, Y. [The University of Tokyo, Tokyo (Japan)

1999-09-30

The Great Hanshin-Awaji Earthquake caused great damage to roads. Not only on highways, but even in regional communities, a considerable number of streets became unusable because of falls of buildings, etc. to roads and occurrence of bumps. It provided obstacles in refuge and rescue activities. In building cities preparing for earthquake in future, it is important to re-evaluate how to make the road network including narrow streets. Therefore, paying attention to the physical distance of the roads in earthquake and the number of the points which people cannot reach, clarified was the relation between those phenomena and the characteristics of towns/roads which the region has. As an example of Higashinada-ward, Kobe-city, this report analyzed the data on the actual state from the aspects written below which become especially important in actions taken immediately after earthquake, and described the information/knowledge obtained therefrom: (1) difference in arrival distance between usually and in earthquake in case of walking from residence place to refuge place; (2) state of occurrence of the points where people cannot reach in going to hospitals by ambulance. (NEDO)

Physics of Earthquake Rupture Propagation

Science.gov (United States)

Xu, Shiqing; Fukuyama, Eiichi; Sagy, Amir; Doan, Mai-Linh

2018-05-01

A comprehensive understanding of earthquake rupture propagation requires the study of not only the sudden release of elastic strain energy during co-seismic slip, but also of other processes that operate at a variety of spatiotemporal scales. For example, the accumulation of the elastic strain energy usually takes decades to hundreds of years, and rupture propagation and termination modify the bulk properties of the surrounding medium that can influence the behavior of future earthquakes. To share recent findings in the multiscale investigation of earthquake rupture propagation, we held a session entitled "Physics of Earthquake Rupture Propagation" during the 2016 American Geophysical Union (AGU) Fall Meeting in San Francisco. The session included 46 poster and 32 oral presentations, reporting observations of natural earthquakes, numerical and experimental simulations of earthquake ruptures, and studies of earthquake fault friction. These presentations and discussions during and after the session suggested a need to document more formally the research findings, particularly new observations and views different from conventional ones, complexities in fault zone properties and loading conditions, the diversity of fault slip modes and their interactions, the evaluation of observational and model uncertainties, and comparison between empirical and physics-based models. Therefore, we organize this Special Issue (SI) of Tectonophysics under the same title as our AGU session, hoping to inspire future investigations. Eighteen articles (marked with "this issue") are included in this SI and grouped into the following six categories.

Failures and suggestions in Earthquake forecasting and prediction

Science.gov (United States)

Sacks, S. I.

2013-12-01

Seismologists have had poor success in earthquake prediction. However, wide ranging observations from earlier great earthquakes show that precursory data can exist. In particular, two aspects seem promising. In agreement with simple physical modeling, b-values decrease in highly loaded fault zones for years before failure. Potentially more usefully, in high stress regions, breakdown of dilatant patches leading to failure can yield expelled water-related observations. The volume increase (dilatancy) caused by high shear stresses decreases the pore pressure. Eventually, water flows back in restoring the pore pressure, promoting failure and expelling the extra water. Of course, in a generally stressed region there may be many small patches that fail, such as observed before the 1975 Haicheng earthquake. Only a few days before the major event will most of the dilatancy breakdown occur in the fault zone itself such as for the Tangshan, 1976 destructive event. Observations of 'water release' effects have been observed before the 1923 great Kanto earthquake, the 1984 Yamasaki event, the 1975 Haicheng and the 1976 Tangshan earthquakes and also the 1995 Kobe earthquake. While there are obvious difficulties in water release observations, not least because there is currently no observational network anywhere, historical data does suggest some promise if we broaden our approach to this difficult subject.

Excel, Earthquakes, and Moneyball: exploring Cascadia earthquake probabilities using spreadsheets and baseball analogies

Science.gov (United States)

Campbell, M. R.; Salditch, L.; Brooks, E. M.; Stein, S.; Spencer, B. D.

2017-12-01

Much recent media attention focuses on Cascadia's earthquake hazard. A widely cited magazine article starts "An earthquake will destroy a sizable portion of the coastal Northwest. The question is when." Stories include statements like "a massive earthquake is overdue", "in the next 50 years, there is a 1-in-10 chance a "really big one" will erupt," or "the odds of the big Cascadia earthquake happening in the next fifty years are roughly one in three." These lead students to ask where the quoted probabilities come from and what they mean. These probability estimates involve two primary choices: what data are used to describe when past earthquakes happened and what models are used to forecast when future earthquakes will happen. The data come from a 10,000-year record of large paleoearthquakes compiled from subsidence data on land and turbidites, offshore deposits recording submarine slope failure. Earthquakes seem to have happened in clusters of four or five events, separated by gaps. Earthquakes within a cluster occur more frequently and regularly than in the full record. Hence the next earthquake is more likely if we assume that we are in the recent cluster that started about 1700 years ago, than if we assume the cluster is over. Students can explore how changing assumptions drastically changes probability estimates using easy-to-write and display spreadsheets, like those shown below. Insight can also come from baseball analogies. The cluster issue is like deciding whether to assume that a hitter's performance in the next game is better described by his lifetime record, or by the past few games, since he may be hitting unusually well or in a slump. The other big choice is whether to assume that the probability of an earthquake is constant with time, or is small immediately after one occurs and then grows with time. This is like whether to assume that a player's performance is the same from year to year, or changes over their career. Thus saying "the chance of

Seismic measures and defence in depth of nuclear power plant. Lessons learned from the great east Japan earthquake

International Nuclear Information System (INIS)

Ochiai, Kanehiro

2011-01-01

The Great East Japan Earthquake occurred in March 11, 2011 brought about severe accident at nuclear power plant, which gave significant lessons to nuclear experts concerned with safety measures. Concepts of defence in depth was basic philosophy to assure safety of nuclear power plant even against uncertainties exceeding design basis. This concept consisted of prevention, monitoring, and action to mitigate consequences of failures such as a series of physical barriers between the reactor core and the environment, which were called multiple safety systems, each with backup and designed to accommodate human error. As for natural disaster, depth of recognition of characteristic of natural phenomena and its effect and engineering judgment was of prime importance. Different waveforms of ground motion at Fukushima and Onagawa at the Great East Japan Earthquake showed that design ground motion should have large uncertainties. To cope with uncertainties of ground motion, robust seismic measures based on experience were such as design of static seismic intensity and rigid structure of natural period less than 0.1 sec. As for tsunami, defence in depth measures were prepared for the cooling of reactor core, spent fuel and related electric generation equipment with taking into account 1) time lag between tsunami generation and arrival, 2) tsunami affected area could be limited by coastal levee or anti-inundation measure, 3) system redundancy could be assured by different locations of equipments and 4) repair works could be done by shipment of replacement equipment from outside due to limitation of affected regional area. Success examples of Onagawa, Tokai unit 2, Fukushima Daiichi unit 6 and Fukushima Daini Nuclear Power Plants could suggest definite tsunami defence in depth measures. Containment vent system as final heat sink and emergency condenser as reactor core cooling at outage should be properly utilized for Fukushima Daiichi unit 1 Nuclear Power Plant. (T. Tanaka)

Premenstrual symptoms and posttraumatic stress disorder in Japanese high school students 9 months after the great East-Japan earthquake.

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Takeda, Takashi; Tadakawa, Mari; Koga, Shoko; Nagase, Satoru; Yaegashi, Nobuo

2013-07-01

On March 11, 2011, the Great East-Japan Earthquake occurred and a massive tsunami hit the northeastern coast of Japan. Catastrophic disasters such as earthquakes and war cause tremendous damage, not only physically but also mentally. Posttraumatic stress disorder (PTSD) is an anxiety disorder that occurs in the aftermath of a traumatic event. Premenstrual syndrome (PMS) is a cluster of psychological and somatic symptoms that are limited to the late luteal phase of the menstrual cycle. Premenstrual dysphoric disorder (PMDD) is considered a severe form of PMS. To determine the relationship between premenstrual symptoms and natural disaster-induced PTSD among Japanese adolescent girls, we conducted a cross-sectional study. Overall, 1489 high school students who belong to two high schools in Sendai, the largest city in northeastern Japan, were assessed 9 months after the earthquake. These schools are located inland, far from the seashore, and were not damaged by the tsunami. Premenstrual symptoms were assessed using the Premenstrual Symptoms Questionnaire, and PTSD symptoms were assessed using the Japanese-language version of Impact of Event Scale-Revised, which is a widely used self-assessment questionnaire about PTSD symptoms. We analyzed the data of 1,180 girls who completed the questionnaires and 118 girls (10.0%) were classified as having PTSD. The prevalence rates of PMDD and moderate to severe PMS increased according to the comorbidity of PTSD (p PMS/PMDD and natural disaster-induced PTSD. The comorbidity of PMS/PMDD and PTSD may complicate the follow-up of both conditions.

Low cost earthquake resistant ferrocement small house

International Nuclear Information System (INIS)

Saleem, M.A.; Ashraf, M.; Ashraf, M.

2008-01-01

The greatest humanitarian challenge faced even today after one year of Kashmir Hazara earthquake is that of providing shelter. Currently on the globe one in seven people live in a slum or refugee camp. The earthquake of October 2005 resulted in a great loss of life and property. This research work is mainly focused on developing a design of small size, low cost and earthquake resistant house. Ferrocement panels are recommended as the main structural elements with lightweight truss roofing system. Earthquake resistance is ensured by analyzing the structure on ETABS for a seismic activity of zone 4. The behavior of structure is found satisfactory under the earthquake loading. An estimate of cost is also presented which shows that it is an economical solution. (author)

Influence of Great East Japan Earthquake on neutron source station in J-PARC

International Nuclear Information System (INIS)

Sakai, Kenji; Sakamoto, Shinichi; Kinoshita, Hidetaka; Seki, Masakazu; Haga, Katsuhiro; Kogawa, Hiroyuki; Wakui, Takashi; Naoe, Takashi; Kasugai, Yoshimi; Tatsumoto, Hideki; Aso, Tomokazu; Hasegawa, Shoichi; Maekawa, Fujio; Oikawa, Kenichi; Ooi, Motoki; Watanabe, Akihiko; Teshigawara, Makoto; Meigo, Shin-ichiro; Ikezaki, Kiyomi; Akutsu, Atsushi; Harada, Masahide; Takada, Hiroshi; Futakawa, Masatoshi

2012-03-01

This report investigates the behavior, damage and restoration of each component in a neutron source station of the Materials and Life Science Experimental Facility (MLF) of J-PARC at the time of the Great East Japan Earthquake (M9.0) and verified the safety design for emergency accidents in the neutron source station. The neutron source station of the MLF at the J-PARC generates neutrons by injecting proton beams into a mercury target, and supplies to user experimental apparatuses. It consists of the mercury target, three moderators filled with supercritical hydrogen, reflectors, water cooling shields, a vessel filled with helium gas, neutron beam shutters, biological-shields and so on. In case of loss of their external electric power supply, a control function for the source station is kept by an emergency power supply. According to interlock sequences in an emergency, a signal for terminating the beam operation is transmitted, the circulators shut down automatically, and the hydrogen gas is released out of the building. On March 11 in 2011, strong shocks caused by the earthquake were observed all over Ibaraki prefecture. At the date, a status of the source station was ready for the restart of beam operation. In the MLF, after strong quakes were detected at the several instruments, the external power supply was lost, all of the circulators shut down automatically, and the hydrogen gas was released. The leakages of mercury, hydrogen and radio-activation gases did not occur. While, the quakes made gaps between the shield blocks and ruptured external pipe lines for compressed air and water by subsidence around the building. But significant damages to the components were not found though the pressure drop of compressed air lines influenced on the mercury target trolley lock system and pneumatic operation values. These results substantiated the validity of the safety design for emergency accidents in the neutron source station in the MLF, and suggested several points

Overview of Historical Earthquake Document Database in Japan and Future Development

Science.gov (United States)

Nishiyama, A.; Satake, K.

2014-12-01

In Japan, damage and disasters from historical large earthquakes have been documented and preserved. Compilation of historical earthquake documents started in the early 20th century and 33 volumes of historical document source books (about 27,000 pages) have been published. However, these source books are not effectively utilized for researchers due to a contamination of low-reliability historical records and a difficulty for keyword searching by characters and dates. To overcome these problems and to promote historical earthquake studies in Japan, construction of text database started in the 21 century. As for historical earthquakes from the beginning of the 7th century to the early 17th century, "Online Database of Historical Documents in Japanese Earthquakes and Eruptions in the Ancient and Medieval Ages" (Ishibashi, 2009) has been already constructed. They investigated the source books or original texts of historical literature, emended the descriptions, and assigned the reliability of each historical document on the basis of written age. Another database compiled the historical documents for seven damaging earthquakes occurred along the Sea of Japan coast in Honshu, central Japan in the Edo period (from the beginning of the 17th century to the middle of the 19th century) and constructed text database and seismic intensity data base. These are now publicized on the web (written only in Japanese). However, only about 9 % of the earthquake source books have been digitized so far. Therefore, we plan to digitize all of the remaining historical documents by the research-program which started in 2014. The specification of the data base will be similar for previous ones. We also plan to combine this database with liquefaction traces database, which will be constructed by other research program, by adding the location information described in historical documents. Constructed database would be utilized to estimate the distributions of seismic intensities and tsunami

New geological perspectives on earthquake recurrence models

International Nuclear Information System (INIS)

Schwartz, D.P.

1997-01-01

In most areas of the world the record of historical seismicity is too short or uncertain to accurately characterize the future distribution of earthquakes of different sizes in time and space. Most faults have not ruptured once, let alone repeatedly. Ultimately, the ability to correctly forecast the magnitude, location, and probability of future earthquakes depends on how well one can quantify the past behavior of earthquake sources. Paleoseismological trenching of active faults, historical surface ruptures, liquefaction features, and shaking-induced ground deformation structures provides fundamental information on the past behavior of earthquake sources. These studies quantify (a) the timing of individual past earthquakes and fault slip rates, which lead to estimates of recurrence intervals and the development of recurrence models and (b) the amount of displacement during individual events, which allows estimates of the sizes of past earthquakes on a fault. When timing and slip per event are combined with information on fault zone geometry and structure, models that define individual rupture segments can be developed. Paleoseismicity data, in the form of timing and size of past events, provide a window into the driving mechanism of the earthquake engine--the cycle of stress build-up and release

Good practice at Onagawa power plant during the 3.11 Great East Japan Earthquake

International Nuclear Information System (INIS)

Wakabayashi, Toshiaki

2016-01-01

This paper describes the situation of Onagawa Nuclear Power Station after The off the Pacific Coast of Tohoku Earthquake on March 11, 2011: (1) outline of situation of nuclear power plant Unit 1, 2 and 3, (2) assumption of push wave from the recognition of the tsunami due to large earthquakes that occurred in the past and tsunami countermeasures, and securement of cooling function at the time of push/pull wave based on emergency seawater pumps, (3) installation of handrail sticks on the central control room monitoring and control panel as a countermeasure from the lessons from the past earthquakes, (4) improvement of the seismic tolerance of facilities, and (5) earthquake resistant reinforcement of main office building and new construction of a seismic isolation office building. As response to emergency situation, the following are described: (1) unification of external response service at the head office, and the helicopter transportation of goods due to power plant needs as the power station support from the head office, and (2) as the countermeasures of on-site power plant, the duplication of information transmission route and the survey/examination and countermeasures by individual teams for each problem (especially, fire at Unit 1 and seawater infiltration at Unit 2). In additive, through the emergency response at the time of The off the Pacific Coast of Tohoku Earthquake, this paper examined the required qualities of an on-site commander based on the experience stories of persons concerned. (A.O.)

Stress transferred by the 1995 Mw = 6.9 Kobe, Japan, shock: Effect on aftershocks and future earthquake probabilities

Science.gov (United States)

Toda, S.; Stein, R.S.; Reasenberg, P.A.; Dieterich, J.H.; Yoshida, A.

1998-01-01

The Kobe earthquake struck at the edge of the densely populated Osaka-Kyoto corridor in southwest Japan. We investigate how the earthquake transferred stress to nearby faults, altering their proximity to failure and thus changing earthquake probabilities. We find that relative to the pre-Kobe seismicity, Kobe aftershocks were concentrated in regions of calculated Coulomb stress increase and less common in regions of stress decrease. We quantify this relationship by forming the spatial correlation between the seismicity rate change and the Coulomb stress change. The correlation is significant for stress changes greater than 0.2-1.0 bars (0.02-0.1 MPa), and the nonlinear dependence of seismicity rate change on stress change is compatible with a state- and rate-dependent formulation for earthquake occurrence. We extend this analysis to future mainshocks by resolving the stress changes on major faults within 100 km of Kobe and calculating the change in probability caused by these stress changes. Transient effects of the stress changes are incorporated by the state-dependent constitutive relation, which amplifies the permanent stress changes during the aftershock period. Earthquake probability framed in this manner is highly time-dependent, much more so than is assumed in current practice. Because the probabilities depend on several poorly known parameters of the major faults, we estimate uncertainties of the probabilities by Monte Carlo simulation. This enables us to include uncertainties on the elapsed time since the last earthquake, the repeat time and its variability, and the period of aftershock decay. We estimate that a calculated 3-bar (0.3-MPa) stress increase on the eastern section of the Arima-Takatsuki Tectonic Line (ATTL) near Kyoto causes fivefold increase in the 30-year probability of a subsequent large earthquake near Kyoto; a 2-bar (0.2-MPa) stress decrease on the western section of the ATTL results in a reduction in probability by a factor of 140 to

Use of Ground Motion Simulations of a Historical Earthquake for the Assessment of Past and Future Urban Risks

Science.gov (United States)

Kentel, E.; Çelik, A.; karimzadeh Naghshineh, S.; Askan, A.

2017-12-01

Erzincan city located in the Eastern part of Turkey at the conjunction of three active faults is one of the most hazardous regions in the world. In addition to several historical events, this city has experienced one of the largest earthquakes during the last century: The 27 December 1939 (Ms=8.0) event. With limited knowledge of the tectonic structure by then, the city center was relocated to the North after the 1939 earthquake by almost 5km, indeed closer to the existing major strike slip fault. This decision coupled with poor construction technologies, led to severe damage during a later event that occurred on 13 March 1992 (Mw=6.6). The 1939 earthquake occurred in the pre-instrumental era in the region with no available local seismograms whereas the 1992 event was only recorded by 3 nearby stations. There are empirical isoseismal maps from both events indicating indirectly the spatial distribution of the damage. In this study, we focus on this region and present a multidisciplinary approach to discuss the different components of uncertainties involved in the assessment and mitigation of seismic risk in urban areas. For this initial attempt, ground motion simulation of the 1939 event is performed to obtain the anticipated ground motions and shaking intensities. Using these quantified results along with the spatial distribution of the observed damage, the relocation decision is assessed and suggestions are provided for future large earthquakes to minimize potential earthquake risks.

Superconducting Gravimeters Detect Gravity Fluctuations Induced by Mw 5.7 Earthquake Along South Pacific Rise Few Hours Before the 2011 Mw 9.0 Tohoku-Oki Earthquake

Directory of Open Access Journals (Sweden)

Keliang Zhang Jin Ma

2014-01-01

Full Text Available Gravity changes sometimes appear before a big earthquake. To determine the possible sources is important for recognizing the mechanism and further geodynamic studies. During the first two hours on March 11 before the Mw 9.0 Tohoku-Oki earthquake, the non-tidal gravity time series of superconducting gravimeters worldwide showed low-frequency (< 0.10 Hz fluctuations with amplitude of ~1 to 4 × 10-8 ms-2 lasting ~10 - 20 minutes. Through comparing global seismicity with the arrival times of seismic waves, we find that the fluctuations were induced by the Mw 5.7 earthquake that occurred at 0:14:54.68 at (53.27°S, 118.18°W along the eastern South Pacific Rise. Several body waves such as P, S are clearly recorded in the station with ~400 km distance to the hypocenter. The fluctuations are in response to the waves that propagate with a velocity of about 4 km s-1. Their amplitudes are proportional to the inverse of the epicentral distances even though the fluctuations of European sites were overlapped with waves associated with a smaller, i.e., Mw 2.6, event in Europe during this period. That is, the Mw 5.7 earthquake induced remarkable gravity fluctuations over long distances at stations all over the world. As such, the foreshocks with larger magnitudes occurred before the Mw 9.0 earthquake would have more significant influence on the gravity recordings and the seismic-wave induced component should be removed during the analysis of anomalies prior to a great earthquake in future studies.

Elevation of Derivatives of Reactive Oxygen Metabolites Elevated in Young "Disaster Responders" in Hypertension due to Great East Japan Earthquake.

Science.gov (United States)

Shiraishi, Yasunaga; Kujiraoka, Takehiko; Hakuno, Daihiko; Masaki, Nobuyuki; Tokuno, Shinichi; Adachi, Takeshi

2016-01-01

There have been very few studies on serum biomarkers associated with hypertension in disaster situations. We assessed biomarkers associated with disaster-related hypertension (DRH) due to the Great East Japan Earthquake of March 2011.We collected blood samples from members of the Japan Self Defense Forces (JSDF) (n = 77) after completing disaster relief operations. We divided them into two groups based on systolic blood pressure. We defined DRH as either systolic blood pressure greater than 140 mmHg or diastolic blood pressure greater than 90 mmHg at the time of completing missions.In subjects with DRH, the mean blood pressure was 143.5 ± 5.0/99.5 ± 2.4 mmHg. Height and body weight measurements were slightly greater in the DRH group but the differences were not significant, and age was significantly higher in the DRH group. There were no differences in serum biochemical tests including metabolic markers, sulfur-containing amino acids, and cytokines. Among nitric oxide-related amino acids, asymmetric dimethylarginine (ADMA) was lower in the DRH group than in the normotension group (0.40 ± 0.02 versus 0.31 ± 0.02 μmol/L P = 0.04). The serum oxidative stress metabolite levels (d-ROMs; indicators of active oxygen metabolite products) were significantly higher in the DRH group (273.6 ± 6.08 versus 313.5 ± 13.7 U.CARR P = 0.016). Using multivariable regression analysis, d-ROMs levels were particularly predictive for DRH.Oxidative stress is associated with DRH in responders to the disaster of the Great East Japan Earthquake.

Report on Disaster Medical Operations with Acupuncture/Massage Therapy after the Great East Japan Earthquake

Directory of Open Access Journals (Sweden)

Shin Takayama

2012-01-01

Full Text Available The Great East Japan Earthquake inflicted immense damage over a wide area of eastern Japan with the consequent tsunami. Department of Traditional Asian Medicine, Tohoku University, started providing medical assistance to the disaster-stricken regions mainly employing traditional Asian therapies. We visited seven evacuation centers in Miyagi and Fukushima Prefecture and provided acupuncture/massage therapy. While massage therapy was performed manually, filiform needles and press tack needles were used to administer acupuncture. In total, 553 people were treated (mean age, 54.0 years; 206 men, 347 women. Assessment by interview showed that the most common complaint was shoulder/back stiffness. The rate of therapy satisfaction was 92.3%. Many people answered that they experienced not only physical but also psychological relief. At the time of the disaster, acupuncture/massage therapy, which has both mental and physical soothing effects, may be a therapeutic approach that can be effectively used in combination with Western medical practices.

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

Post-earthquake building safety inspection: Lessons from the Canterbury, New Zealand, earthquakes

Science.gov (United States)

Marshall, J.; Jaiswal, Kishor; Gould, N.; Turner, F.; Lizundia, B.; Barnes, J.

2013-01-01

The authors discuss some of the unique aspects and lessons of the New Zealand post-earthquake building safety inspection program that was implemented following the Canterbury earthquake sequence of 2010–2011. The post-event safety assessment program was one of the largest and longest programs undertaken in recent times anywhere in the world. The effort engaged hundreds of engineering professionals throughout the country, and also sought expertise from outside, to perform post-earthquake structural safety inspections of more than 100,000 buildings in the city of Christchurch and the surrounding suburbs. While the building safety inspection procedure implemented was analogous to the ATC 20 program in the United States, many modifications were proposed and implemented in order to assess the large number of buildings that were subjected to strong and variable shaking during a period of two years. This note discusses some of the key aspects of the post-earthquake building safety inspection program and summarizes important lessons that can improve future earthquake response.

Crowd-Sourced Global Earthquake Early Warning

Science.gov (United States)

Minson, S. E.; Brooks, B. A.; Glennie, C. L.; Murray, J. R.; Langbein, J. O.; Owen, S. E.; Iannucci, B. A.; Hauser, D. L.

2014-12-01

Although earthquake early warning (EEW) has shown great promise for reducing loss of life and property, it has only been implemented in a few regions due, in part, to the prohibitive cost of building the required dense seismic and geodetic networks. However, many cars and consumer smartphones, tablets, laptops, and similar devices contain low-cost versions of the same sensors used for earthquake monitoring. If a workable EEW system could be implemented based on either crowd-sourced observations from consumer devices or very inexpensive networks of instruments built from consumer-quality sensors, EEW coverage could potentially be expanded worldwide. Controlled tests of several accelerometers and global navigation satellite system (GNSS) receivers typically found in consumer devices show that, while they are significantly noisier than scientific-grade instruments, they are still accurate enough to capture displacements from moderate and large magnitude earthquakes. The accuracy of these sensors varies greatly depending on the type of data collected. Raw coarse acquisition (C/A) code GPS data are relatively noisy. These observations have a surface displacement detection threshold approaching ~1 m and would thus only be useful in large Mw 8+ earthquakes. However, incorporating either satellite-based differential corrections or using a Kalman filter to combine the raw GNSS data with low-cost acceleration data (such as from a smartphone) decreases the noise dramatically. These approaches allow detection thresholds as low as 5 cm, potentially enabling accurate warnings for earthquakes as small as Mw 6.5. Simulated performance tests show that, with data contributed from only a very small fraction of the population, a crowd-sourced EEW system would be capable of warning San Francisco and San Jose of a Mw 7 rupture on California's Hayward fault and could have accurately issued both earthquake and tsunami warnings for the 2011 Mw 9 Tohoku-oki, Japan earthquake.

Epidemiological evaluation of cat health at a first-response animal shelter in Fukushima, following the Great East Japan Earthquakes of 2011.

Science.gov (United States)

Tanaka, Aki; Kass, Philip H; Martinez-Lopez, Beatriz; Hayama, Shinichi

2017-01-01

The Great East Japan Earthquakes of March 11, 2011 caused immense harm to the community and subsequent nuclear accident in Fukushima Prefecture extended the damage. Local residents were forced to evacuated without pets and the left behind animals were rescued from the restricted zone one month later. Unplanned animal rescue and unregulated sheltering caused secondary damage to animals such as disease epidemics at impounded animal shelter. The purpose of this study was to retrospectively evaluate the incidence of upper respiratory infection (URI) and diarrhea in cats at the first response animal shelter in Fukushima, and investigate factors affecting the duration of disease and determinants of treatments performed. Eighty percent and 59% of impounded cats developed URI, 71% and 54% of cats developed diarrhea, and 91% and 83% of cats had at least one disease in 2011 and 2012, respectively. Uses of multiple drug administration (more than five drugs) was associated with prolonged URI and diarrhea. Multiple antibiotics, antihistamines, interferon, and steroids were associated with relapse of and prolonged URI. Developing a standardized treatment protocol for commonly observed diseases at Japanese animal shelters to prevent and control diseases, to promote animal welfare, and protect public health in the face of future disasters is overdue.

Tsunamigenic earthquake simulations using experimentally derived friction laws

Science.gov (United States)

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

2018-03-01

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

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.

Supports for libraries'restoration from the Great East Japan Earthquake : Challenges we address at Miyagi Prefectural Library

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Kumagai, Shinichiro

This article overviews the situations of damage and reconstruction of mainly public libraries in Miyagi Prefecture about 9 months after the Great East Japan Earthquake. Serious damage of library buildings was due not only to the tsunami or seismic sea wave but to violent shaking, the latter less reported by the media. We at the Miyagi Prefectural Library implemented reconstruction assistance for regional public libraries in both direct and indirect ways. Among them, we report in detail on the support we offered until the Minami-sanriku Town Library reopened its service. We highlight a prefectural library's role, acting between supporters and those supportees, to consider the necessity of middle organizations. We clarify what challenges we face and examine how best to provide assistance in case of large-scale disasters.

Experimental evidence that thrust earthquake ruptures might open faults.

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Gabuchian, Vahe; Rosakis, Ares J; Bhat, Harsha S; Madariaga, Raúl; Kanamori, Hiroo

2017-05-18

Many of Earth's great earthquakes occur on thrust faults. These earthquakes predominantly occur within subduction zones, such as the 2011 moment magnitude 9.0 eathquake in Tohoku-Oki, Japan, or along large collision zones, such as the 1999 moment magnitude 7.7 earthquake in Chi-Chi, Taiwan. Notably, these two earthquakes had a maximum slip that was very close to the surface. This contributed to the destructive tsunami that occurred during the Tohoku-Oki event and to the large amount of structural damage caused by the Chi-Chi event. The mechanism that results in such large slip near the surface is poorly understood as shallow parts of thrust faults are considered to be frictionally stable. Here we use earthquake rupture experiments to reveal the existence of a torquing mechanism of thrust fault ruptures near the free surface that causes them to unclamp and slip large distances. Complementary numerical modelling of the experiments confirms that the hanging-wall wedge undergoes pronounced rotation in one direction as the earthquake rupture approaches the free surface, and this torque is released as soon as the rupture breaks the free surface, resulting in the unclamping and violent 'flapping' of the hanging-wall wedge. Our results imply that the shallow extent of the seismogenic zone of a subducting interface is not fixed and can extend up to the trench during great earthquakes through a torquing mechanism.

Concern over radiation exposure and psychological distress among rescue workers following the Great East Japan Earthquake

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Matsuoka Yutaka

2012-05-01

Full Text Available Abstract Background On March 11, 2011, the Great East Japan Earthquake and tsunami that followed caused severe damage along Japans northeastern coastline and to the Fukushima Daiichi nuclear power plant. To date, there are few reports specifically examining psychological distress in rescue workers in Japan. Moreover, it is unclear to what extent concern over radiation exposure has caused psychological distress to such workers deployed in the disaster area. Methods One month after the disaster, 424 of 1816 (24% disaster medical assistance team workers deployed to the disaster area were assessed. Concern over radiation exposure was evaluated by a single self-reported question. General psychological distress was assessed with the Kessler 6 scale (K6, depressive symptoms with the Center for Epidemiologic Studies Depression Scale (CES-D, fear and sense of helplessness with the Peritraumatic Distress Inventory (PDI, and posttraumatic stress symptoms with the Impact of Event Scale-Revised (IES-R. Results Radiation exposure was a concern for 39 (9.2% respondents. Concern over radiation exposure was significantly associated with higher scores on the K6, CES-D, PDI, and IES-R. After controlling for age, occupation, disaster operation experience, duration of time spent watching earthquake news, and past history of psychiatric illness, these associations remained significant in men, but did not remain significant in women for the CES-D and PDI scores. Conclusion The findings suggest that concern over radiation exposure was strongly associated with psychological distress. Reliable, accurate information on radiation exposure might reduce deployment-related distress in disaster rescue workers.

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

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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.

Coping with the challenges of early disaster response: 24 years of field hospital experience after earthquakes.

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Bar-On, Elhanan; Abargel, Avi; Peleg, Kobi; Kreiss, Yitshak

2013-10-01

To propose strategies and recommendations for future planning and deployment of field hospitals after earthquakes by comparing the experience of 4 field hospitals deployed by The Israel Defense Forces (IDF) Medical Corps in Armenia, Turkey, India and Haiti. Quantitative data regarding the earthquakes were collected from published sources; data regarding hospital activity were collected from IDF records; and qualitative information was obtained from structured interviews with key figures involved in the missions. The hospitals started operating between 89 and 262 hours after the earthquakes. Their sizes ranged from 25 to 72 beds, and their personnel numbered between 34 and 100. The number of patients treated varied from 1111 to 2400. The proportion of earthquake-related diagnoses ranged from 28% to 67% (P earthquakes, patient caseload and treatment requirements varied widely. The variables affecting the patient profile most significantly were time until deployment, total number of injured, availability of adjacent medical facilities, and possibility of evacuation from the disaster area. When deploying a field hospital in the early phase after an earthquake, a wide variability in patient caseload should be anticipated. Customization is difficult due to the paucity of information. Therefore, early deployment necessitates full logistic self-sufficiency and operational versatility. Also, collaboration with local and international medical teams can greatly enhance treatment capabilities.

Southern Peru desert shattered by the great 2001 earthquake: Implications for paleoseismic and paleo-El Niño–Southern Oscillation records

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Keefer, David K.; Moseley, Michael E.

2004-01-01

In the desert region around the coastal city of Ilo, the great southern Peru earthquake of June 23, 2001 (8.2–8.4 moment magnitude), produced intense and widespread ground-failure effects. These effects included abundant landslides, pervasive ground cracking, microfracturing of surficial hillslope materials, collapse of drainage banks over long stretches, widening of hillside rills, and lengthening of first-order tributary channels. We have coined the term “shattered landscape” to describe the severity of these effects. Long-term consequences of this landscape shattering are inferred to include increased runoff and sediment transport during postearthquake rainstorms. This inference was confirmed during the first minor postearthquake rainstorm there, which occurred in June and July of 2002. Greater amounts of rainfall in this desert region have historically been associated with El Niño events. Previous studies of an unusual paleoflood deposit in this region have concluded that it is the product of El Niño-generated precipitation falling on seismically disturbed landscapes. The effects of the 2001 earthquake and 2002 rainstorm support that conclusion. PMID:15263069

Earthquake forewarning in the Cascadia region

Science.gov (United States)

Gomberg, Joan S.; Atwater, Brian F.; Beeler, Nicholas M.; Bodin, Paul; Davis, Earl; Frankel, Arthur; Hayes, Gavin P.; McConnell, Laura; Melbourne, Tim; Oppenheimer, David H.; Parrish, John G.; Roeloffs, Evelyn A.; Rogers, Gary D.; Sherrod, Brian; Vidale, John; Walsh, Timothy J.; Weaver, Craig S.; Whitmore, Paul M.

2015-08-10

This report, prepared for the National Earthquake Prediction Evaluation Council (NEPEC), is intended as a step toward improving communications about earthquake hazards between information providers and users who coordinate emergency-response activities in the Cascadia region of the Pacific Northwest. NEPEC charged a subcommittee of scientists with writing this report about forewarnings of increased probabilities of a damaging earthquake. We begin by clarifying some terminology; a “prediction” refers to a deterministic statement that a particular future earthquake will or will not occur. In contrast to the 0- or 100-percent likelihood of a deterministic prediction, a “forecast” describes the probability of an earthquake occurring, which may range from >0 to processes or conditions, which may include Increased rates of M>4 earthquakes on the plate interface north of the Mendocino region 

Questionnaire investigation for the earthquake in Honjo city and Yazawa city, Akita Prefecture; Jishin ni kansuru ishiki chosa (Akitaken Honjoshi oyobi Yuzawashi ni okeru anketo kara)

Energy Technology Data Exchange (ETDEWEB)

Nogoshi, M [Akita University, Akita (Japan). College of Education; Kabutoya, S

1996-05-01

Consciousness for the earthquake was investigated by questionnaire surveys made in Honjo City and Yuzawa City, Akita Pref. in October 1995 twelve years after the Nihonkai Chubu Earthquake (M=7.7) in May 1983. The survey was conducted in terms of 27 items including personality, memory, knowledge/interest, psychology/action, mental attitude/preparations, wishes for researchers and administration, etc. Also included were the items on the Great Hanshin-Awaji Earthquake and the earthquake blank areas. The number of distributed questionnaires and the recovery rate of them are 1500 and 79.2% in Honjo City, and 1700 and 84.7% in Yuzawa City. From the survey, it was found that people have a lot of knowledge of and high interest in the earthquake and well remember it, and a lot of people know of tsunami, liquefaction phenomena, and the earthquake blank area. Further, they are afraid of earthquakes and think of their actions to be taken in case of earthquake. However, most people are little prepared for earthquakes. Important future subjects were suggested for the study of disaster prevention measures. 13 figs.

Earthquake Clusters and Spatio-temporal Migration of earthquakes in Northeastern Tibetan Plateau: a Finite Element Modeling

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Sun, Y.; Luo, G.

2017-12-01

Seismicity in a region is usually characterized by earthquake clusters and earthquake migration along its major fault zones. However, we do not fully understand why and how earthquake clusters and spatio-temporal migration of earthquakes occur. The northeastern Tibetan Plateau is a good example for us to investigate these problems. In this study, we construct and use a three-dimensional viscoelastoplastic finite-element model to simulate earthquake cycles and spatio-temporal migration of earthquakes along major fault zones in northeastern Tibetan Plateau. We calculate stress evolution and fault interactions, and explore effects of topographic loading and viscosity of middle-lower crust and upper mantle on model results. Model results show that earthquakes and fault interactions increase Coulomb stress on the neighboring faults or segments, accelerating the future earthquakes in this region. Thus, earthquakes occur sequentially in a short time, leading to regional earthquake clusters. Through long-term evolution, stresses on some seismogenic faults, which are far apart, may almost simultaneously reach the critical state of fault failure, probably also leading to regional earthquake clusters and earthquake migration. Based on our model synthetic seismic catalog and paleoseismic data, we analyze probability of earthquake migration between major faults in northeastern Tibetan Plateau. We find that following the 1920 M 8.5 Haiyuan earthquake and the 1927 M 8.0 Gulang earthquake, the next big event (M≥7) in northeastern Tibetan Plateau would be most likely to occur on the Haiyuan fault.

Obesity in elementary school children after the Great East Japan Earthquake.

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Moriyama, Hidenori; Fuchimukai, Toru; Kondo, Naoki; Takayama, John I

2018-03-01

Rikuzentakata was one of the cities most devastated by the Great East Japan Earthquake on 11 March 2011. Many buildings were swept away or destroyed and affected families were placed into temporary housing. The aim of this study was to determine the impact of long-term temporary housing on the body mass index (BMI) of elementary school children living in Rikuzentakata City. A retrospective cohort study of was carried out of students attending 1st-3rd grade in 2010, and 4th-6th grade in 2013, in eight elementary schools in Rikuzentakata City. Height and weight were measured annually. We compared changes in BMI between children in temporary housing and those in permanent housing. Separately, parents of students attending one of the elementary schools were surveyed in 2013. Of 526 children in the present study, 32% were living in temporary housing. The prevalence of obesity climbed from 5.3% in 2010 to 7.8% in 2013 in the temporary housing group, and from 7.6% to 7.8% in the permanent housing group. BMI z-score in the temporary housing group increased by 0.102 points between 2010 and 2013 (P comic books and their walking commute time had decreased by 2 min compared with before the disaster. Obesity prevalence and BMI z-score increased in children in temporary housing compared with permanent housing. A more sedentary lifestyle may explain this trend. It is important for policy makers and health-care providers to recognize potential consequences of long-term residence in temporary housing. © 2017 Japan Pediatric Society.

Resilience, post-traumatic growth, and work engagement among health care professionals after the Great East Japan Earthquake: A 4-year prospective follow-up study.

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Nishi, Daisuke; Kawashima, Yuzuru; Noguchi, Hiroko; Usuki, Masato; Yamashita, Akihiro; Koido, Yuichi; Matsuoka, Yutaka J

2016-07-22

Although attention has been paid to post-traumatic stress disorder (PTSD) among health care professionals after disasters, the impact of traumatic events on their work has not been elucidated. The aim of this study was to examine whether disaster-related distress, resilience, and post-traumatic growth (PTG) affect work engagement among health care professionals who had been deployed to the areas affected by the Great East Japan Earthquake that occurred on March 11, 2011. We recruited disaster medical assistance team members who were engaged in rescue activities after the earthquake. The short version of the Resilience Scale (RS-14) and Peritraumatic Distress Inventory (PDI) were administered one month after the earthquake, and the short form of Posttraumatic Growth Inventory (SF-PTGI) and Utrecht Work Engagement Scale (UWES) were administered four years after the earthquake. Work engagement is composed of vigor, dedication, and absorption. Regression analyses were used to examine the relationship of UWES with RS-14, PDI, and SF-PTGI. We obtained baseline data of 254 participants in April 2011, and 191 (75.2%) completed the follow-up assessment between December 2014 and March 2015. The results showed that RS-14 predicted vigor, dedication, and absorption; in addition, SF-PTGI was positively related with these three parameters (pwork engagement among health care professionals after disasters. These findings could be useful for establishing a support system after rescue activities during a large-scale disaster and for managing work-related stress among health care professionals.

Preparing for creative responses to “beyond assumed level” disasters: lessons from the ICT management in the 2011 Great East Japan earthquake crisis

Directory of Open Access Journals (Sweden)

Mihoko Sakurai

2012-12-01

Full Text Available A survey of the municipal government ICT divisions during and after the 2011 Great East Japan Earthquake and Tsunami crisis reveals the need for creative responses for “beyond assumed level” disasters. Complexity and diversity of the damage were simply too great for any plans to assume. Resident needs toward the municipal governments were also diverse and changed quickly as the time went by. The research also indicates that there would be ways to strengthen the capabilities to execute such spontaneous responses. Creative solutions executed during the 3.11 crisis were supported by the existence of open source software available on the net and skilled engineers that were capable of exploiting them. Frugal information system will be useful to improve preparedness for creative responses

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

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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.

Seismic properties of the Longmen Shan complex: Implications for the moment magnitude of the great 2008 Wenchuan earthquake in China

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Sun, Shengsi; Ji, Shaocheng; Wang, Qian; Wang, Hongcai; Long, Changxing; Salisbury, Matthew

2012-09-01

The 12 May 2008 Wenchuan earthquake is the largest active tectonic event reported to date in Sichuan (China). We have experimentally calibrated, up to 800 MPa, seismic and elastic properties of 12 representative samples from the Longmen Shan complex in which this great earthquake took place and its coseismic ruptures nucleated and propagated. Most of the samples show little Vp or Vs anisotropy at pressures above the microcrack-closure pressure (Pc = 200-300 MPa), and so the variation of anisotropy with pressure provides important hints for the preferred orientation of microcracks in the nonlinear poroelastic regime below Pc. Geothermal and rheological profiles indicate that the focal depth (~ 19 km) corresponds to the base of the schizosphere, below which the Longmen Shan complex switches from the brittle to ductile behavior. The investigation reveals that the crust of the Longmen Shan range consists of 4 layers from the surface to the Moho: Layer 1: Vp < 4.88 km/s (0-3 km thick, sedimentary rocks such as limestone, sandstone, conglomerate, and mudstone); Layer 2: Vp = 5.95-6.25 km/s (25-28 km thick, felsic rocks); Layer 3: Vp = 6.55 km/s (10 km thick, 67.5% felsic and 32.5% mafic rocks); and Layer 4: Vp = 6.90 km/s (8 km thick, 20.0% felsic and 80.0% mafic rocks). The average Vp/Vs ratio of 1.71 or Poisson's ratio of 0.24 calculated for the whole crust is consistent with the results measured using teleseismic receiver function techniques. This study also offers necessary information for broadband simulations of strong ground motions in the assessment and forecast of earthquake hazards in the region. Furthermore, the study, which yields a moment magnitude of 7.9-8.0 given the variation in the dip of the coseismic ruptures and the uncertainty in the depth to which the coseismic rupture may propagate downwards below the depth of the mainshock hypocenter, presents the first accurate quantification of the 2008 Wenchuan earthquake's size.

Earthquake-relief APWR (Advanced Pressurized Water Reactor) plants

International Nuclear Information System (INIS)

Yoshinaga, Hidekazu; Oshibe, Toshihiro; Yamaura, Yoshihisa; Kokubo, Eiji

1999-01-01

The anti-seismic design conditions for nuclear power stations are extremely severe in Japan. Therefore, various measures, including the increase in building wall thickness and in the number of equipment supports, need to be implemented to satisfy the necessary anti-seismic design. This is one of the causes of the increase in the construction cost of power stations. Meanwhile, a seismic isolation system, which mitigates an input earthquake motion, has been attracting attention in the general construction industry since the Great Hansin Earthquake in 1995. An increasing number of buildings employing such a system have been constructed. The system is being more popular and socially accepted. At the same time, the anti-seismic nuclear power stations have already been operated in France and South Africa. Various reviews and researches are promoted in Japan to adopt the seismic isolation system in nuclear power stations. The building and equipment designs when the seismic isolation system is applied to APWR are reviewed based on the experience in Japan and overseas. Specifically, reviews were conducted on the following items and their technical and economical feasibility has been well confirmed: Earthquake-relief equipment properties. Building design. Equipment design. The reliability and economy on the building and equipment designs shall further be enhanced in order to maximize the advantages of seismic isolation system in the future. (author)

Seismotectonics of the Nicobar Swarm and the geodynamic implications for the 2004 Great Sumatran Earthquake

Science.gov (United States)

Lister, Gordon

2017-04-01

The Great Sumatran Earthquake took place on 26th December 2004. One month into the aftershock sequence, a dense swarm of earthquakes took place beneath the Andaman Sea, northeast of the Nicobar Islands. The swarm continued for ˜11 days, rapidly decreasing in intensity towards the end of that period. Unlike most earthquake swarms, the Nicobar cluster was characterised by a large number of shocks with moment magnitude exceeding five. This meant that centroid moment tensor data could be determined, and this data in turn allows geometric analysis of inferred fault plane motions. The classification obtained using program eQuakes shows aftershocks falling into distinct spatial groups. Thrusts dominate in the south (in the Sumatran domain), and normal faults dominate in the north (in the Andaman domain). Strike-slip faults are more evenly spread. They occur on the Sumatran wrench system, for example, but also on the Indian plate itself. Orientation groups readily emerge from such an analysis. Temporal variation in behaviour is immediately evident, changing after ˜12 months. Orientation groups in the first twelve months are consistent with margin perpendicular extension beneath the Andaman Sea (i.e. mode II megathrust behaviour) whereas afterward the pattern of deformation appears to have reverted to that expected in consequence of relative plate motion. In the first twelve months, strike-slip motion appears to have taken place on faults that are sub-parallel to spreading segments in the Andaman Sea. By early 2006 however normal fault clusters formed that showed ˜N-S extension across these spreading segments had resumed, while the overall density of aftershocks in the Andaman segment had considerably diminished. Throughout this entire period the Sumatran segment exhibited aftershock sequences consistent with ongoing Mode I megathrust behaviour. The Nicobar Swarm marks the transition from one sort of slab dynamics to the other. The earthquake swarm may have been

Simulating Earthquakes for Science and Society: Earthquake Visualizations Ideal for use in Science Communication and Education

Science.gov (United States)

de Groot, R.

2008-12-01

The Southern California Earthquake Center (SCEC) has been developing groundbreaking computer modeling capabilities for studying earthquakes. These visualizations were initially shared within the scientific community but have recently gained visibility via television news coverage in Southern California. Computers have opened up a whole new world for scientists working with large data sets, and students can benefit from the same opportunities (Libarkin & Brick, 2002). For example, The Great Southern California ShakeOut was based on a potential magnitude 7.8 earthquake on the southern San Andreas fault. The visualization created for the ShakeOut was a key scientific and communication tool for the earthquake drill. This presentation will also feature SCEC Virtual Display of Objects visualization software developed by SCEC Undergraduate Studies in Earthquake Information Technology interns. According to Gordin and Pea (1995), theoretically visualization should make science accessible, provide means for authentic inquiry, and lay the groundwork to understand and critique scientific issues. This presentation will discuss how the new SCEC visualizations and other earthquake imagery achieve these results, how they fit within the context of major themes and study areas in science communication, and how the efficacy of these tools can be improved.

Visible Earthquakes: a web-based tool for visualizing and modeling InSAR earthquake data

Science.gov (United States)

Funning, G. J.; Cockett, R.

2012-12-01

InSAR (Interferometric Synthetic Aperture Radar) is a technique for measuring the deformation of the ground using satellite radar data. One of the principal applications of this method is in the study of earthquakes; in the past 20 years over 70 earthquakes have been studied in this way, and forthcoming satellite missions promise to enable the routine and timely study of events in the future. Despite the utility of the technique and its widespread adoption by the research community, InSAR does not feature in the teaching curricula of most university geoscience departments. This is, we believe, due to a lack of accessibility to software and data. Existing tools for the visualization and modeling of interferograms are often research-oriented, command line-based and/or prohibitively expensive. Here we present a new web-based interactive tool for comparing real InSAR data with simple elastic models. The overall design of this tool was focused on ease of access and use. This tool should allow interested nonspecialists to gain a feel for the use of such data and greatly facilitate integration of InSAR into upper division geoscience courses, giving students practice in comparing actual data to modeled results. The tool, provisionally named 'Visible Earthquakes', uses web-based technologies to instantly render the displacement field that would be observable using InSAR for a given fault location, geometry, orientation, and slip. The user can adjust these 'source parameters' using a simple, clickable interface, and see how these affect the resulting model interferogram. By visually matching the model interferogram to a real earthquake interferogram (processed separately and included in the web tool) a user can produce their own estimates of the earthquake's source parameters. Once satisfied with the fit of their models, users can submit their results and see how they compare with the distribution of all other contributed earthquake models, as well as the mean and median

Playing against nature: improving earthquake hazard mitigation

Science.gov (United States)

Stein, S. A.; Stein, J.

2012-12-01

The great 2011 Tohoku earthquake dramatically demonstrated the need to improve earthquake and tsunami hazard assessment and mitigation policies. The earthquake was much larger than predicted by hazard models, and the resulting tsunami overtopped coastal defenses, causing more than 15,000 deaths and $210 billion damage. Hence if and how such defenses should be rebuilt is a challenging question, because the defences fared poorly and building ones to withstand tsunamis as large as March's is too expensive,. A similar issue arises along the Nankai Trough to the south, where new estimates warning of tsunamis 2-5 times higher than in previous models raise the question of what to do, given that the timescale on which such events may occur is unknown. Thus in the words of economist H. Hori, "What should we do in face of uncertainty? Some say we should spend our resources on present problems instead of wasting them on things whose results are uncertain. Others say we should prepare for future unknown disasters precisely because they are uncertain". Thus society needs strategies to mitigate earthquake and tsunami hazards that make economic and societal sense, given that our ability to assess these hazards is poor, as illustrated by highly destructive earthquakes that often occur in areas predicted by hazard maps to be relatively safe. Conceptually, we are playing a game against nature "of which we still don't know all the rules" (Lomnitz, 1989). Nature chooses tsunami heights or ground shaking, and society selects the strategy to minimize the total costs of damage plus mitigation costs. As in any game of chance, we maximize our expectation value by selecting the best strategy, given our limited ability to estimate the occurrence and effects of future events. We thus outline a framework to find the optimal level of mitigation by balancing its cost against the expected damages, recognizing the uncertainties in the hazard estimates. This framework illustrates the role of the

Computational methods in earthquake engineering

CERN Document Server

Plevris, Vagelis; Lagaros, Nikos

2017-01-01

This is the third book in a series on Computational Methods in Earthquake Engineering. The purpose of this volume is to bring together the scientific communities of Computational Mechanics and Structural Dynamics, offering a wide coverage of timely issues on contemporary Earthquake Engineering. This volume will facilitate the exchange of ideas in topics of mutual interest and can serve as a platform for establishing links between research groups with complementary activities. The computational aspects are emphasized in order to address difficult engineering problems of great social and economic importance. .

Thermal infrared anomalies of several strong earthquakes.

Science.gov (United States)

Wei, Congxin; Zhang, Yuansheng; Guo, Xiao; Hui, Shaoxing; Qin, Manzhong; Zhang, Ying

2013-01-01

In the history of earthquake thermal infrared research, it is undeniable that before and after strong earthquakes there are significant thermal infrared anomalies which have been interpreted as preseismic precursor in earthquake prediction and forecasting. In this paper, we studied the characteristics of thermal radiation observed before and after the 8 great earthquakes with magnitude up to Ms7.0 by using the satellite infrared remote sensing information. We used new types of data and method to extract the useful anomaly information. Based on the analyses of 8 earthquakes, we got the results as follows. (1) There are significant thermal radiation anomalies before and after earthquakes for all cases. The overall performance of anomalies includes two main stages: expanding first and narrowing later. We easily extracted and identified such seismic anomalies by method of "time-frequency relative power spectrum." (2) There exist evident and different characteristic periods and magnitudes of thermal abnormal radiation for each case. (3) Thermal radiation anomalies are closely related to the geological structure. (4) Thermal radiation has obvious characteristics in abnormal duration, range, and morphology. In summary, we should be sure that earthquake thermal infrared anomalies as useful earthquake precursor can be used in earthquake prediction and forecasting.

Contribution of soil sciences for recovering from damages by the Great East Japan Earthquake

International Nuclear Information System (INIS)

Miwa, Eitaro; Miyazaki, Tsuyoshi; Nanzyo, Masami

2014-01-01

This symposium was held in September 2013, under the joint hosting of Science Council of Japan, Agricultural Academy of Japan, and Japanese Society of Soil Science and Plant Nutrition, as one of the programs of the Nagoya convention of Japanese Society of Soil Science and Plant Nutrition. The theme was the contribution of soil science to the restoration from the Great East Japan Earthquake and the issues involved in this. As the restoration from the tsunami, the following two topics were presented: 'Situation of Miyagi Prefecture and challenge of soil science', and 'Technological measures for the resumption of farming in tsunami-hit areas in Soma City, Fukushima Prefecture.' As the restoration from the radiation damage caused by Fukushima Daiichi Nuclear Power Station Accident, the following four topics were presented: 'Cooperation between villagers and scholars at Iitate Village; efforts for survey and decontamination with the hands of villagers,' 'Cesium fixation related to on-site soil,' 'Concentration and separation of cesium,' and 'Volume reduction of contaminated soil.' This paper summarizes these six topics of lectures, keynote comments by other specialists and relevant persons, and the atmosphere of the convention on the day. (A.O)

Source modeling of the 2015 Mw 7.8 Nepal (Gorkha) earthquake sequence: Implications for geodynamics and earthquake hazards

Science.gov (United States)

McNamara, D. E.; Yeck, W. L.; Barnhart, W. D.; Schulte-Pelkum, V.; Bergman, E.; Adhikari, L. B.; Dixit, A.; Hough, S. E.; Benz, H. M.; Earle, P. S.

2017-09-01

The Gorkha earthquake on April 25th, 2015 was a long anticipated, low-angle thrust-faulting event on the shallow décollement between the India and Eurasia plates. We present a detailed multiple-event hypocenter relocation analysis of the Mw 7.8 Gorkha Nepal earthquake sequence, constrained by local seismic stations, and a geodetic rupture model based on InSAR and GPS data. We integrate these observations to place the Gorkha earthquake sequence into a seismotectonic context and evaluate potential earthquake hazard. Major results from this study include (1) a comprehensive catalog of calibrated hypocenters for the Gorkha earthquake sequence; (2) the Gorkha earthquake ruptured a 150 × 60 km patch of the Main Himalayan Thrust (MHT), the décollement defining the plate boundary at depth, over an area surrounding but predominantly north of the capital city of Kathmandu (3) the distribution of aftershock seismicity surrounds the mainshock maximum slip patch; (4) aftershocks occur at or below the mainshock rupture plane with depths generally increasing to the north beneath the higher Himalaya, possibly outlining a 10-15 km thick subduction channel between the overriding Eurasian and subducting Indian plates; (5) the largest Mw 7.3 aftershock and the highest concentration of aftershocks occurred to the southeast the mainshock rupture, on a segment of the MHT décollement that was positively stressed towards failure; (6) the near surface portion of the MHT south of Kathmandu shows no aftershocks or slip during the mainshock. Results from this study characterize the details of the Gorkha earthquake sequence and provide constraints on where earthquake hazard remains high, and thus where future, damaging earthquakes may occur in this densely populated region. Up-dip segments of the MHT should be considered to be high hazard for future damaging earthquakes.

Rapid estimation of the moment magnitude of large earthquake from static strain changes

Science.gov (United States)

Itaba, S.

2014-12-01

The 2011 off the Pacific coast of Tohoku earthquake, of moment magnitude (Mw) 9.0, occurred on March 11, 2011. Based on the seismic wave, the prompt report of the magnitude which the Japan Meteorological Agency announced just after earthquake occurrence was 7.9, and it was considerably smaller than an actual value. On the other hand, using nine borehole strainmeters of Geological Survey of Japan, AIST, we estimated a fault model with Mw 8.7 for the earthquake on the boundary between the Pacific and North American plates. This model can be estimated about seven minutes after the origin time, and five minute after wave arrival. In order to grasp the magnitude of a great earthquake earlier, several methods are now being suggested to reduce the earthquake disasters including tsunami (e.g., Ohta et al., 2012). Our simple method of using strain steps is one of the strong methods for rapid estimation of the magnitude of great earthquakes.

Peptic Ulcers in Fukushima Prefecture Related to the Great East Japan Earthquake, Tsunami and Nuclear Accident

Science.gov (United States)

Hikichi, Takuto; Sato, Masaki; Watanabe, Ko; Nakamura, Jun; Kikuchi, Hitomi; Ejiri, Yutaka; Ishihata, Ryoichi; Irisawa, Atsushi; Takahashi, Yuta; Saito, Hironobu; Takagi, Tadayuki; Suzuki, Rei; Sugimoto, Mitsuru; Konno, Naoki; Waragai, Yuichi; Asama, Hiroyuki; Takasumi, Mika; Sato, Yuki; Ohira, Hiromasa; Obara, Katsutoshi

2017-01-01

Objective Due to the Great East Japan Earthquake, which occurred in March 2011, many residents of Fukushima Prefecture were affected by a radiation accident in addition to suffering loss or damage from the earthquake and the subsequent tsunami. The aim of this study was to evaluate the actual condition of patients with peptic ulcers related to the disaster. Methods Patients with peptic ulcers at six hospitals in three different regions of Fukushima Prefecture during the two months following the disaster and the corresponding period of the year before and the year after the disaster were enrolled in this study. Changes by period and region in the number of esophagogastroduodenoscopy (EGD) examinations and the number of peptic ulcer patients were evaluated as the primary endpoints. Changes in the frequencies of hemorrhagic ulcers were evaluated by period and by region as secondary endpoints. Results The numbers of EGDs and peptic ulcer cases compared to the previous year decreased in 2011 and then increased in 2012. However, the ratio of hemorrhagic ulcers to peptic ulcers was higher in 2011 (51.9%) than in 2010 (38.1%) and 2012 (31.1%), and the 2011 hemorrhagic ulcer ratio was the highest at 63.6% in the coastal area. Regarding bleeding cases during 2011, the rate at 1 month after the disaster (64.1%) was higher than the rate at 2 months after the disaster (40.5%) (p=0.033). Conclusion The number of patients with peptic ulcers did not increase immediately following the disaster in Fukushima Prefecture. However, the rate of bleeding patients increased soon after the disaster, especially in the coastal area. PMID:29269647

Modified-Fibonacci-Dual-Lucas method for earthquake prediction

Science.gov (United States)

Boucouvalas, A. C.; Gkasios, M.; Tselikas, N. T.; Drakatos, G.

2015-06-01

The FDL method makes use of Fibonacci, Dual and Lucas numbers and has shown considerable success in predicting earthquake events locally as well as globally. Predicting the location of the epicenter of an earthquake is one difficult challenge the other being the timing and magnitude. One technique for predicting the onset of earthquakes is the use of cycles, and the discovery of periodicity. Part of this category is the reported FDL method. The basis of the reported FDL method is the creation of FDL future dates based on the onset date of significant earthquakes. The assumption being that each occurred earthquake discontinuity can be thought of as a generating source of FDL time series The connection between past earthquakes and future earthquakes based on FDL numbers has also been reported with sample earthquakes since 1900. Using clustering methods it has been shown that significant earthquakes (conjunct Sun, Moon opposite Sun, Moon conjunct or opposite North or South Modes. In order to test improvement of the method we used all +8R earthquakes recorded since 1900, (86 earthquakes from USGS data). We have developed the FDL numbers for each of those seeds, and examined the earthquake hit rates (for a window of 3, i.e. +-1 day of target date) and for <6.5R. The successes are counted for each one of the 86 earthquake seeds and we compare the MFDL method with the FDL method. In every case we find improvement when the starting seed date is on the planetary trigger date prior to the earthquake. We observe no improvement only when a planetary trigger coincided with the earthquake date and in this case the FDL method coincides with the MFDL. Based on the MDFL method we present the prediction method capable of predicting global events or localized earthquakes and we will discuss the accuracy of the method in as far as the prediction and location parts of the method. We show example calendar style predictions for global events as well as for the Greek region using

Surface latent heat flux as an earthquake precursor

Directory of Open Access Journals (Sweden)

S. Dey

2003-01-01

Full Text Available The analysis of surface latent heat flux (SLHF from the epicentral regions of five recent earthquakes that occurred in close proximity to the oceans has been found to show anomalous behavior. The maximum increase of SLHF is found 2–7 days prior to the main earthquake event. This increase is likely due to an ocean-land-atmosphere interaction. The increase of SLHF prior to the main earthquake event is attributed to the increase in infrared thermal (IR temperature in the epicentral and surrounding region. The anomalous increase in SLHF shows great potential in providing early warning of a disastrous earthquake, provided that there is a better understanding of the background noise due to the tides and monsoon in surface latent heat flux. Efforts have been made to understand the level of background noise in the epicentral regions of the five earthquakes considered in the present paper. A comparison of SLHF from the epicentral regions over the coastal earthquakes and the earthquakes that occurred far away from the coast has been made and it has been found that the anomalous behavior of SLHF prior to the main earthquake event is only associated with the coastal earthquakes.

The great East Japan earthquake

Energy Technology Data Exchange (ETDEWEB)

Fluke, R.

2011-06-15

'Full text:' More formally called the Tohoku-Chihou-Taiheiyo-Oki Earthquake of March 11, 2011, it was the ensuing tsunami that caused the most death and destruction to the north-east coastal region of Japan. It is also what caused the multiple meltdowns at Fukushima Dai-ichi. Reactor Unit 1, ironically, was scheduled to be permanently shut down for decommissioning just two weeks later. The Fukushima Dai-ichi nuclear power plant has a tsunami protection barrier designed for the worst recorded tsunami in that area since 1896 - to a height of 5.7 m. The plant itself is on an elevated grade of about 10 m. The tsunami, reported to be 14-15 m, caused inundation of the entire site with at least four metres of seawater. The seawater flooded the turbine building and damaged electrical equipment including the emergency diesel generators, leaving the entire six-unit nuclear power plan without any source of AC power, known as the 'station blackout scenario'. There are numerous reports available on-line at various sites. The Japanese Government report is frank and forthcoming on the causes and the lessons learned, and the lAEA Mission report is in-depth and well presented, not only as a factual account of the events but as a unified source of the conclusions and lessons learned. Photos of the catastrophe are available at the TEPCO web site: http://www.tepco.co.jp/en/index-e.html. In this edition of the Bulletin there is a 'layman's' description of CANDU and BWR design in terms of the fundamental safety principles - Control, Cool and Contain as well as a description of how these principles were met, or not met at Fukushima Dai-ichi. Also, an excerpt from the IAEA Expert Mission is included. We 'technocrats' sometimes forget about the human aspects of a nuclear disaster. An essay by Dr. Michael Edwards is included entitled 'Psychology, Philosophy and Nuclear Science'. Other references to the events appear throughout this

The great East Japan earthquake

International Nuclear Information System (INIS)

Fluke, R.

2011-01-01

'Full text:' More formally called the Tohoku-Chihou-Taiheiyo-Oki Earthquake of March 11, 2011, it was the ensuing tsunami that caused the most death and destruction to the north-east coastal region of Japan. It is also what caused the multiple meltdowns at Fukushima Dai-ichi. Reactor Unit 1, ironically, was scheduled to be permanently shut down for decommissioning just two weeks later. The Fukushima Dai-ichi nuclear power plant has a tsunami protection barrier designed for the worst recorded tsunami in that area since 1896 - to a height of 5.7 m. The plant itself is on an elevated grade of about 10 m. The tsunami, reported to be 14-15 m, caused inundation of the entire site with at least four metres of seawater. The seawater flooded the turbine building and damaged electrical equipment including the emergency diesel generators, leaving the entire six-unit nuclear power plan without any source of AC power, known as the 'station blackout scenario'. There are numerous reports available on-line at various sites. The Japanese Government report is frank and forthcoming on the causes and the lessons learned, and the lAEA Mission report is in-depth and well presented, not only as a factual account of the events but as a unified source of the conclusions and lessons learned. Photos of the catastrophe are available at the TEPCO web site: http://www.tepco.co.jp/en/index-e.html. In this edition of the Bulletin there is a 'layman's' description of CANDU and BWR design in terms of the fundamental safety principles - Control, Cool and Contain as well as a description of how these principles were met, or not met at Fukushima Dai-ichi. Also, an excerpt from the IAEA Expert Mission is included. We 'technocrats' sometimes forget about the human aspects of a nuclear disaster. An essay by Dr. Michael Edwards is included entitled 'Psychology, Philosophy and Nuclear Science'. Other references to the events appear throughout this edition.(author)

Mega-city and great earthquake distributions: the search of basic links.

Science.gov (United States)

Levin, Boris; Sasorova, Elena; Domanski, Andrej

2013-04-01

The ever-increasing population density in large metropolitan cities near major active faults (e.g. Tokyo, Lisbon, San-Francisco, et al.) and recent catastrophic earthquakes in Japan, Indonesia and Haiti (loss of life more 500000), highlight the need for searching of causal relationships between distributions of earthquake epicenters and mega-cities at the Earth [1]. The latitudinal distribution of mega-cities calculated with using Internet data base, discovers a curious peculiarity: the density of large city numbers, related to 10-degree latitude interval, demonstrates two maximums in middle latitudes (±30-40°) on both sides of the equator. These maximums are separated by clean local minimum near equator, and such objects (mega-cities) are practically absent in the high latitudes. In the last two decades, it was shown [2, 3, 4] that a seismic activity of the Earth is described by the similar bimodal latitudinal distribution. The similarity between bimodal distributions for geophysical phenomena and mega-city locations attracts common attention. The peak values in the both distributions (near ±35°) correspond to location of well-known "critical latitudes" at the planet. These latitudes were determined [5], as the lines of intersection of a sphere and a spheroid of equal volume (±35°15'52″). Increasing of the angular velocity of a celestial body rotation leads to growth of oblateness of planet, and vice versa, the oblateness is decreasing with reducing of velocity of rotation. So, well-known effect of the Earth rotation instability leads to small pulsations of the geoid. In the critical latitudes, the geoid radius-vector is equal to the radius of sphere. The zones of near critical latitudes are characterized by high density of faults in the Earth crust and manifestation of some geological peculiarities (hot spot distribution, large ore deposit distribution, et al.). The active faults existence has led to an emanation of depth fluids, which created the good

How Should Disaster Base Hospitals Prepare for Dialysis Therapy after Earthquakes? Introduction of Double Water Piping Circuits Provided by Well Water System.

Science.gov (United States)

Ikegaya, Naoki; Seki, George; Ohta, Nobutaka

2016-01-01

After earthquakes, continuing dialysis for patients with ESRD and patients suffering from crush syndrome is the serious problem. In this paper, we analyzed the failure of the provision of dialysis services observed in recent disasters and discussed how to prepare for disasters to continue dialysis therapy. Japan has frequently experienced devastating earthquakes. A lot of dialysis centers could not continue dialysis treatment owing to damage caused by these earthquakes. The survey by Japanese Society for Dialysis Treatment (JSDT) after the Great East Japan Earthquake in 2011 showed that failure of lifelines such as electric power and water supply was the leading cause of the malfunction of dialysis treatment. Our hospital is located in Shizuoka Prefecture, where one of the biggest earthquakes is predicted to occur in the near future. In addition to reconstructing earthquake-resistant buildings and facilities, we therefore have adopted double electric and water lifelines by introducing emergency generators and well water supply systems. It is very important to inform politicians, bureaucrats, and local water departments that dialysis treatment, a life sustaining therapy for patients with end stage renal diseases, requires a large amount of water. We cannot prevent an earthquake but can curb the extent of a disaster by preparing for earthquakes.

Adaptively smoothed seismicity earthquake forecasts for Italy

Directory of Open Access Journals (Sweden)

Yan Y. Kagan

2010-11-01

Full Text Available We present a model for estimation of the probabilities of future earthquakes of magnitudes m ≥ 4.95 in Italy. This model is a modified version of that proposed for California, USA, by Helmstetter et al. [2007] and Werner et al. [2010a], and it approximates seismicity using a spatially heterogeneous, temporally homogeneous Poisson point process. The temporal, spatial and magnitude dimensions are entirely decoupled. Magnitudes are independently and identically distributed according to a tapered Gutenberg-Richter magnitude distribution. We have estimated the spatial distribution of future seismicity by smoothing the locations of past earthquakes listed in two Italian catalogs: a short instrumental catalog, and a longer instrumental and historic catalog. The bandwidth of the adaptive spatial kernel is estimated by optimizing the predictive power of the kernel estimate of the spatial earthquake density in retrospective forecasts. When available and reliable, we used small earthquakes of m ≥ 2.95 to reveal active fault structures and 29 probable future epicenters. By calibrating the model with these two catalogs of different durations to create two forecasts, we intend to quantify the loss (or gain of predictability incurred when only a short, but recent, data record is available. Both forecasts were scaled to five and ten years, and have been submitted to the Italian prospective forecasting experiment of the global Collaboratory for the Study of Earthquake Predictability (CSEP. An earlier forecast from the model was submitted by Helmstetter et al. [2007] to the Regional Earthquake Likelihood Model (RELM experiment in California, and with more than half of the five-year experimental period over, the forecast has performed better than the others.

A way to synchronize models with seismic faults for earthquake forecasting

DEFF Research Database (Denmark)

González, Á.; Gómez, J.B.; Vázquez-Prada, M.

2006-01-01

Numerical models are starting to be used for determining the future behaviour of seismic faults and fault networks. Their final goal would be to forecast future large earthquakes. In order to use them for this task, it is necessary to synchronize each model with the current status of the actual....... Earthquakes, though, provide indirect but measurable clues of the stress and strain status in the lithosphere, which should be helpful for the synchronization of the models. The rupture area is one of the measurable parameters of earthquakes. Here we explore how it can be used to at least synchronize fault...... models between themselves and forecast synthetic earthquakes. Our purpose here is to forecast synthetic earthquakes in a simple but stochastic (random) fault model. By imposing the rupture area of the synthetic earthquakes of this model on other models, the latter become partially synchronized...

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

Science.gov (United States)

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

2017-12-01

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

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.

Threat of an earthquake right under the capital in Japan

Science.gov (United States)

Rikitake, T.

1990-01-01

Tokyo, Japan's capital, has been enjoying a seismically quiet period following the 1923 Kanto earthquake of magnitude 7.9 that killed more than 140,000 people. Such a quiet period seems likely to be a repetition of the 80-year quiescence after the great 1703 Genroku earthquake of magntidue 8.2 that occurred in an epicentral area adjacent to that of the 1923 Kanto earthquake. In 1784, seismic activity immediately under the capital area revived with occasional occurrence of magnitude 6 to 7 shocks. Earthquakes of this class tended to occur more frequently as time went on and they eventually culminated in the 1923 Kanto earthquake. As more than 60 years have passed since the Kanto earthquake, we may well expect another revival of activity immediately under the capital area. 

Fighting and preventing post-earthquake fires in nuclear power plant

International Nuclear Information System (INIS)

Lu Xuefeng; Zhang Xin

2011-01-01

Nuclear power plant post-earthquake fires will cause not only personnel injury, severe economic loss, but also serious environmental pollution. For the moment, nuclear power is in a position of rapid development in China. Considering the earthquake-prone characteristics of our country, it is of great engineering importance to investigate the nuclear power plant post-earthquake fires. This article analyzes the cause, influential factors and development characteristics of nuclear power plant post-earthquake fires in details, and summarizes the three principles should be followed in fighting and preventing nuclear power plant post-earthquake fires, such as solving problems in order of importance and urgency, isolation prior to prevention, immediate repair and regular patrol. Three aspects were pointed out that should be paid attention in fighting and preventing post-earthquake fires. (authors)

Lichenometry dating of rock collapse related to the great Lisbon Earthquake (1755) at the SE part of Spain

Science.gov (United States)

Perez-Lopez, Raul; Rodriguez-Pascua, Miguel Angel; Silva, Pablo G.; Bischoff, James L.; Owen, Lewis A.; Giner-Robles, Jorge L.; Díez-Herrero, Andres

2010-05-01

"De una montaña, se desprendió una parte" (A large part of a mountain has fallen down). This sentence was extracted from an ancient text written at the end of the 18th Century, in relation with the great Earthquake of Lisbon in 1755 (Martínez-Solares, 2001), and describing the rock collapse recorded near the small town of Agramón, 50 km southeastward of Albacete city (SE of Spain). Up to now, archaeologists have suggested this rock collapse to the archaeological site of "El Tolmo de Minateda", a small butte (420 m long) of calcarenitic sandstone bedrock with a flat top and scarped cliffs (20m high) bordering the butte. This ancient city was habited by several civilizations from Bronze Ages to modern times (i.e. Iberians, Roman, Visigoths, Muslims, Medieval ages, etc.). The landscape of this area is characterized by a flat terrain with isolated relict structural buttes consisting of Late Neogene marine sandstones created by differential erosion. The site exhibits three different stages of massive rock collapse. The oldest is located at the north of the site while the younger is located at the south part of the site and affecting Visigothic stone carved tombs. Archaeologists have postulated that the youngest of these was triggered by the Lisbon earthquake of 1755. We have carried out a lichenometric analysis over the free-faces of the rock blocks, with the aim of testing the postulate. For our purpose, we have calculated the calibrated growth curve for Aspicilia Radiosa (Hoff.), which yields a linear growth of 0.2425 mm per yr (R2 = 0.97, N=20). This growth rate was determined for the time interval from 800 BP yrs to the present by two different approaches: (1) rates obtained from cemetery measurements (200 yrs BP) and (2) rates determined from well-dated archaeological monuments (200-800 yrs BP). Our analysis revealed that the age of the rock-falling was in the year 1754 AD ±4. Thus, our results confirm that this collapse of ca. 5000 m3 of volume was triggered

The future of future-oriented cognition in non-humans: theory and the empirical case of the great apes.

Science.gov (United States)

Osvath, Mathias; Martin-Ordas, Gema

2014-11-05

One of the most contested areas in the field of animal cognition is non-human future-oriented cognition. We critically examine key underlying assumptions in the debate, which is mainly preoccupied with certain dichotomous positions, the most prevalent being whether or not 'real' future orientation is uniquely human. We argue that future orientation is a theoretical construct threatening to lead research astray. Cognitive operations occur in the present moment and can be influenced only by prior causation and the environment, at the same time that most appear directed towards future outcomes. Regarding the current debate, future orientation becomes a question of where on various continua cognition becomes 'truly' future-oriented. We question both the assumption that episodic cognition is the most important process in future-oriented cognition and the assumption that future-oriented cognition is uniquely human. We review the studies on future-oriented cognition in the great apes to find little doubt that our closest relatives possess such ability. We conclude by urging that future-oriented cognition not be viewed as expression of some select set of skills. Instead, research into future-oriented cognition should be approached more like research into social and physical cognition. © 2014 The Author(s) Published by the Royal Society. All rights reserved.

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

Global earthquake casualties due to secondary effects: A quantitative analysis for improving rapid loss analyses

Science.gov (United States)

Marano, K.D.; Wald, D.J.; Allen, T.I.

2010-01-01

This study presents a quantitative and geospatial description of global losses due to earthquake-induced secondary effects, including landslide, liquefaction, tsunami, and fire for events during the past 40 years. These processes are of great importance to the US Geological Survey's (USGS) Prompt Assessment of Global Earthquakes for Response (PAGER) system, which is currently being developed to deliver rapid earthquake impact and loss assessments following large/significant global earthquakes. An important question is how dominant are losses due to secondary effects (and under what conditions, and in which regions)? Thus, which of these effects should receive higher priority research efforts in order to enhance PAGER's overall assessment of earthquakes losses and alerting for the likelihood of secondary impacts? We find that while 21.5% of fatal earthquakes have deaths due to secondary (non-shaking) causes, only rarely are secondary effects the main cause of fatalities. The recent 2004 Great Sumatra-Andaman Islands earthquake is a notable exception, with extraordinary losses due to tsunami. The potential for secondary hazards varies greatly, and systematically, due to regional geologic and geomorphic conditions. Based on our findings, we have built country-specific disclaimers for PAGER that address potential for each hazard (Earle et al., Proceedings of the 14th World Conference of the Earthquake Engineering, Beijing, China, 2008). We will now focus on ways to model casualties from secondary effects based on their relative importance as well as their general predictability. ?? Springer Science+Business Media B.V. 2009.

Plan for 3-D full-scale earthquake testing facility

International Nuclear Information System (INIS)

Ohtani, K.

2001-01-01

Based on the lessons learnt from the Great Hanshin-Awaji Earthquake, National Research Institute for Earth Science and Disaster Prevention plan to construct the 3-D Full-Scale Earthquake Testing Facility. This will be the world's largest and strongest shaking table facility. This paper describes the outline of the project for this facility. This facility will be completed in early 2005. (author)

An Integrated and Interdisciplinary Model for Predicting the Risk of Injury and Death in Future Earthquakes.

Science.gov (United States)

Shapira, Stav; Novack, Lena; Bar-Dayan, Yaron; Aharonson-Daniel, Limor

2016-01-01

A comprehensive technique for earthquake-related casualty estimation remains an unmet challenge. This study aims to integrate risk factors related to characteristics of the exposed population and to the built environment in order to improve communities' preparedness and response capabilities and to mitigate future consequences. An innovative model was formulated based on a widely used loss estimation model (HAZUS) by integrating four human-related risk factors (age, gender, physical disability and socioeconomic status) that were identified through a systematic review and meta-analysis of epidemiological data. The common effect measures of these factors were calculated and entered to the existing model's algorithm using logistic regression equations. Sensitivity analysis was performed by conducting a casualty estimation simulation in a high-vulnerability risk area in Israel. the integrated model outcomes indicated an increase in the total number of casualties compared with the prediction of the traditional model; with regard to specific injury levels an increase was demonstrated in the number of expected fatalities and in the severely and moderately injured, and a decrease was noted in the lightly injured. Urban areas with higher populations at risk rates were found more vulnerable in this regard. The proposed model offers a novel approach that allows quantification of the combined impact of human-related and structural factors on the results of earthquake casualty modelling. Investing efforts in reducing human vulnerability and increasing resilience prior to an occurrence of an earthquake could lead to a possible decrease in the expected number of casualties.

Exploring geological and socio-demographic factors associated with under-five mortality in the Wenchuan earthquake using neural network model.

Science.gov (United States)

Hu, Yi; Wang, Jinfeng; Li, Xiaohong; Ren, Dan; Driskell, Luke; Zhu, Jun

2012-01-01

On 12 May 2008, a devastating earthquake occurred in Sichuan Province, China, taking tens of thousands of lives and destroying the homes of millions of people. Among the large number of dead or missing were children, particularly children aged less than five years old, a fact which drew significant media attention. To obtain relevant information specifically to aid further studies and future preventative measures, a neural network model was proposed to explore some geological and socio-demographic factors associated with earthquake-related child mortality. Sensitivity analysis showed that topographic slope (mean 35.76%), geomorphology (mean 24.18%), earthquake intensity (mean 13.68%), and average income (mean 11%) had great contributions to child mortality. These findings could provide some clues to researchers for further studies and to policy makers in deciding how and where preventive measures and corresponding policies should be implemented in the reconstruction of communities.

Dynamic Parameters of the 2015 Nepal Gorkha Mw7.8 Earthquake Constrained by Multi-observations

Science.gov (United States)

Weng, H.; Yang, H.

2017-12-01

Dynamic rupture model can provide much detailed insights into rupture physics that is capable of assessing future seismic risk. Many studies have attempted to constrain the slip-weakening distance, an important parameter controlling friction behavior of rock, for several earthquakes based on dynamic models, kinematic models, and direct estimations from near-field ground motion. However, large uncertainties of the values of the slip-weakening distance still remain, mostly because of the intrinsic trade-offs between the slip-weakening distance and fault strength. Here we use a spontaneously dynamic rupture model to constrain the frictional parameters of the 25 April 2015 Mw7.8 Nepal earthquake, by combining with multiple seismic observations such as high-rate cGPS data, strong motion data, and kinematic source models. With numerous tests we find the trade-off patterns of final slip, rupture speed, static GPS ground displacements, and dynamic ground waveforms are quite different. Combining all the seismic constraints we can conclude a robust solution without a substantial trade-off of average slip-weakening distance, 0.6 m, in contrast to previous kinematical estimation of 5 m. To our best knowledge, this is the first time to robustly determine the slip-weakening distance on seismogenic fault from seismic observations. The well-constrained frictional parameters may be used for future dynamic models to assess seismic hazard, such as estimating the peak ground acceleration (PGA) etc. Similar approach could also be conducted for other great earthquakes, enabling broad estimations of the dynamic parameters in global perspectives that can better reveal the intrinsic physics of earthquakes.

On anti-earthquake design procedure of equipment and pipings in near future

International Nuclear Information System (INIS)

Shibata, H.

1981-01-01

The requirement of anti-earthquake design of nuclear power plants is getting severe year by year. The author will try to discuss how to control its severity and how to find a proper design procedure for licensing of new plants under such severe requirements. On the other hand we suffered from the enormous volumes of documents. To decrease such volumes, the format of documents should be standardized as well as the design procedure standardization. Starting from this point, we need the research and development on the following subjects: i) Standardization of design procedure. ii) Standardization of document. iii) Establishment of standard review procedure using computer. iv) Standardization of earthquake-resistant designed equipment. v) Standardization of anti-earthquake design procedure of piping systems. vi) Introducing margin evaluation procedure to design procedure. vii) Introducing proving test procedure of active component to design procedure. viii) Establishment of evaluation of human reliability in design, fabrication, inspection procedures. ix) Establishment of the proper relation of seismic trigger level and post-earthquake design procedures. (orig./HP)

Earthquake casualty models within the USGS Prompt Assessment of Global Earthquakes for Response (PAGER) system

Science.gov (United States)

Jaiswal, Kishor; Wald, David J.; Earle, Paul S.; Porter, Keith A.; Hearne, Mike

2011-01-01

Since the launch of the USGS’s Prompt Assessment of Global Earthquakes for Response (PAGER) system in fall of 2007, the time needed for the U.S. Geological Survey (USGS) to determine and comprehend the scope of any major earthquake disaster anywhere in the world has been dramatically reduced to less than 30 min. PAGER alerts consist of estimated shaking hazard from the ShakeMap system, estimates of population exposure at various shaking intensities, and a list of the most severely shaken cities in the epicentral area. These estimates help government, scientific, and relief agencies to guide their responses in the immediate aftermath of a significant earthquake. To account for wide variability and uncertainty associated with inventory, structural vulnerability and casualty data, PAGER employs three different global earthquake fatality/loss computation models. This article describes the development of the models and demonstrates the loss estimation capability for earthquakes that have occurred since 2007. The empirical model relies on country-specific earthquake loss data from past earthquakes and makes use of calibrated casualty rates for future prediction. The semi-empirical and analytical models are engineering-based and rely on complex datasets including building inventories, time-dependent population distributions within different occupancies, the vulnerability of regional building stocks, and casualty rates given structural collapse.

Proposal of great eastern Japan earthquake. Message from Fukushima Medical University

International Nuclear Information System (INIS)

Kikuchi, Shin-ichi

2012-01-01

Described are what Fukushima Medical University (FMU) faced and how FMU responded at Fukushima Daiichi Power Plant (FDPP) Accident by hydrogen explosions (Mar. 12 and 14, 2011) following the Great Eastern Japan Earthquake (Mar. 11). The Accident accompanying the forced evacuation of resident in the area 20 km afar from FDPP brought about the concern, fear and anger, different from those in the neighboring Miyagi Prefecture; and strong psychosomatic stress; as well as the significant alteration of composition of generation in population and in sickness proportion in the whole Prefecture. Under these circumstances, FMU decided to hold information in common and make a service window single, to give the top leadership with rough-and-ready practice and a flexible policy, which all were the president's responsibility for making staff work relieved and united. For holding information in common, frequent meetings of the whole FMU personnel were held (42 times from Mar. 11 to Nov.) and of managing staff (81 times until Nov.). During the period, FMU took measures to meet with the situation of patient receiving and transporting, measures against rumor, and cooperation with related medical institutions. Medicare support included the acute phase medicare, and planning and practice of healthcare management for >30 years onward in the Prefecture. The author summarizes 9 lessons proposed from the Disaster to be considered hereafter, like the system perfection at an emergency, more education about radiation for the resident and medicare staff, measures for aging of engineers and scientists related to atomic energy, and so on. As well, 6 lessons are summarized for the next generation using old aphorism and recent commentary in media. The people should follow the excellent leader at crisis; but it's the problem whether there is such a leader on site or in administration at the very time. (T.T.)

Prediction of strong earthquake motions on rock surface using evolutionary process models

International Nuclear Information System (INIS)

Kameda, H.; Sugito, M.

1984-01-01

Stochastic process models are developed for prediction of strong earthquake motions for engineering design purposes. Earthquake motions with nonstationary frequency content are modeled by using the concept of evolutionary processes. Discussion is focused on the earthquake motions on bed rocks which are important for construction of nuclear power plants in seismic regions. On this basis, two earthquake motion prediction models are developed, one (EMP-IB Model) for prediction with given magnitude and epicentral distance, and the other (EMP-IIB Model) to account for the successive fault ruptures and the site location relative to the fault of great earthquakes. (Author) [pt

Prospective testing of Coulomb short-term earthquake forecasts

Science.gov (United States)

Jackson, D. D.; Kagan, Y. Y.; Schorlemmer, D.; Zechar, J. D.; Wang, Q.; Wong, K.

2009-12-01

Earthquake induced Coulomb stresses, whether static or dynamic, suddenly change the probability of future earthquakes. Models to estimate stress and the resulting seismicity changes could help to illuminate earthquake physics and guide appropriate precautionary response. But do these models have improved forecasting power compared to empirical statistical models? The best answer lies in prospective testing in which a fully specified model, with no subsequent parameter adjustments, is evaluated against future earthquakes. The Center of Study of Earthquake Predictability (CSEP) facilitates such prospective testing of earthquake forecasts, including several short term forecasts. Formulating Coulomb stress models for formal testing involves several practical problems, mostly shared with other short-term models. First, earthquake probabilities must be calculated after each “perpetrator” earthquake but before the triggered earthquakes, or “victims”. The time interval between a perpetrator and its victims may be very short, as characterized by the Omori law for aftershocks. CSEP evaluates short term models daily, and allows daily updates of the models. However, lots can happen in a day. An alternative is to test and update models on the occurrence of each earthquake over a certain magnitude. To make such updates rapidly enough and to qualify as prospective, earthquake focal mechanisms, slip distributions, stress patterns, and earthquake probabilities would have to be made by computer without human intervention. This scheme would be more appropriate for evaluating scientific ideas, but it may be less useful for practical applications than daily updates. Second, triggered earthquakes are imperfectly recorded following larger events because their seismic waves are buried in the coda of the earlier event. To solve this problem, testing methods need to allow for “censoring” of early aftershock data, and a quantitative model for detection threshold as a function of

Rupture Propagation through the Big Bend of the San Andreas Fault: A Dynamic Modeling Case Study of the Great Earthquake of 1857

Science.gov (United States)

Lozos, J.

2017-12-01

The great San Andreas Fault (SAF) earthquake of 9 January 1857, estimated at M7.9, was one of California's largest historic earthquakes. Its 360 km rupture trace follows the Carrizo and Mojave segments of the SAF, including the 30° compressional Big Bend in the fault. If 1857 were a characteristic rupture, the hazard implications for southern California would be dire, especially given the inferred 150 year recurrence interval for this section of the fault. However, recent paleoseismic studies in this region suggest that 1857-type events occur less frequently than single-segment Carrizo or Mojave ruptures, and that the hinge of the Big Bend is a barrier to through-going rupture. Here, I use 3D dynamic rupture modeling to attempt to reproduce the rupture length and surface slip distribution of the 1857 earthquake, to determine which physical conditions allow rupture to negotiate the Big Bend of the SAF. These models incorporate the nonplanar geometry of the SAF, an observation-based heterogeneous regional velocity structure (SCEC CVM), and a regional stress field from seismicity literature. Under regional stress conditions, I am unable to produce model events that both match the observed surface slip on the Carrizo and Mojave segments of the SAF and include rupture through the hinge of the Big Bend. I suggest that accumulated stresses at the bend hinge from multiple smaller Carrizo or Mojave ruptures may be required to allow rupture through the bend — a concept consistent with paleoseismic observations. This study may contribute to understanding the cyclicity of hazard associated with the southern-central SAF.

Earthquake Drill using the Earthquake Early Warning System at an Elementary School

Science.gov (United States)

Oki, Satoko; Yazaki, Yoshiaki; Koketsu, Kazuki

2010-05-01

Japan frequently suffers from many kinds of disasters such as earthquakes, typhoons, floods, volcanic eruptions, and landslides. On average, we lose about 120 people a year due to natural hazards in this decade. Above all, earthquakes are noteworthy, since it may kill thousands of people in a moment like in Kobe in 1995. People know that we may have "a big one" some day as long as we live on this land and that what to do; retrofit houses, appliance heavy furniture to walls, add latches to kitchen cabinets, and prepare emergency packs. Yet most of them do not take the action, and result in the loss of many lives. It is only the victims that learn something from the earthquake, and it has never become the lore of the nations. One of the most essential ways to reduce the damage is to educate the general public to be able to make the sound decision on what to do at the moment when an earthquake hits. This will require the knowledge of the backgrounds of the on-going phenomenon. The Ministry of Education, Culture, Sports, Science and Technology (MEXT), therefore, offered for public subscription to choose several model areas to adopt scientific education to the local elementary schools. This presentation is the report of a year and half courses that we had at the model elementary school in Tokyo Metropolitan Area. The tectonic setting of this area is very complicated; there are the Pacific and Philippine Sea plates subducting beneath the North America and the Eurasia plates. The subduction of the Philippine Sea plate causes mega-thrust earthquakes such as the 1923 Kanto earthquake (M 7.9) making 105,000 fatalities. A magnitude 7 or greater earthquake beneath this area is recently evaluated to occur with a probability of 70 % in 30 years. This is of immediate concern for the devastating loss of life and property because the Tokyo urban region now has a population of 42 million and is the center of approximately 40 % of the nation's activities, which may cause great global

Finite-fault slip model of the 2016 Mw 7.5 Chiloé earthquake, southern Chile, estimated from Sentinel-1 data

Science.gov (United States)

Xu, Wenbin

2017-05-01

Subduction earthquakes have been widely studied in the Chilean subduction zone, but earthquakes occurring in its southern part have attracted less research interest primarily due to its lower rate of seismic activity. Here I use Sentinel-1 interferometric synthetic aperture radar (InSAR) data and range offset measurements to generate coseismic crustal deformation maps of the 2016 Mw 7.5 Chiloé earthquake in southern Chile. I find a concentrated crustal deformation with ground displacement of approximately 50 cm in the southern part of the Chiloé island. The best fitting fault model shows a pure thrust-fault motion on a shallow dipping plane orienting 4° NNE. The InSAR-determined moment is 2.4 × 1020 Nm with a shear modulus of 30 GPa, equivalent to Mw 7.56, which is slightly lower than the seismic moment. The model shows that the slip did not reach the trench, and it reruptured part of the fault that ruptured in the 1960 Mw 9.5 earthquake. The 2016 event has only released a small portion of the accumulated strain energy on the 1960 rupture zone, suggesting that the seismic hazard of future great earthquakes in southern Chile is high.

Data base pertinent to earthquake design basis

International Nuclear Information System (INIS)

Sharma, R.D.

1988-01-01

Mitigation of earthquake risk from impending strong earthquakes is possible provided the hazard can be assessed, and translated into appropriate design inputs. This requires defining the seismic risk problem, isolating the risk factors and quantifying risk in terms of physical parameters, which are suitable for application in design. Like all other geological phenomena, past earthquakes hold the key to the understanding of future ones. Quantificatio n of seismic risk at a site calls for investigating the earthquake aspects of the site region and building a data base. The scope of such investigations is il lustrated in Figure 1 and 2. A more detailed definition of the earthquake problem in engineering design is given elsewhere (Sharma, 1987). The present document discusses the earthquake data base, which is required to support a seismic risk evaluation programme in the context of the existing state of the art. (author). 8 tables, 10 figs., 54 refs

CN earthquake prediction algorithm and the monitoring of the future strong Vrancea events

International Nuclear Information System (INIS)

Moldoveanu, C.L.; Radulian, M.; Novikova, O.V.; Panza, G.F.

2002-01-01

The strong earthquakes originating at intermediate-depth in the Vrancea region (located in the SE corner of the highly bent Carpathian arc) represent one of the most important natural disasters able to induce heavy effects (high tool of casualties and extensive damage) in the Romanian territory. The occurrence of these earthquakes is irregular, but not infrequent. Their effects are felt over a large territory, from Central Europe to Moscow and from Greece to Scandinavia. The largest cultural and economical center exposed to the seismic risk due to the Vrancea earthquakes is Bucharest. This metropolitan area (230 km 2 wide) is characterized by the presence of 2.5 million inhabitants (10% of the country population) and by a considerable number of high-risk structures and infrastructures. The best way to face strong earthquakes is to mitigate the seismic risk by using the two possible complementary approaches represented by (a) the antiseismic design of structures and infrastructures (able to support strong earthquakes without significant damage), and (b) the strong earthquake prediction (in terms of alarm intervals declared for long, intermediate or short-term space-and time-windows). The intermediate term medium-range earthquake prediction represents the most realistic target to be reached at the present state of knowledge. The alarm declared in this case extends over a time window of about one year or more, and a space window of a few hundreds of kilometers. In the case of Vrancea events the spatial uncertainty is much less, being of about 100 km. The main measures for the mitigation of the seismic risk allowed by the intermediate-term medium-range prediction are: (a) verification of the buildings and infrastructures stability and reinforcement measures when required, (b) elaboration of emergency plans of action, (c) schedule of the main actions required in order to restore the normality of the social and economical life after the earthquake. The paper presents the

Resource utilization in the emergency department of a tertiary care university-based hospital in Tokyo before and after the 2011 Great East Japan earthquake and tsunami.

Science.gov (United States)

Shimada, Mai; Tanabe, Aska; Gunshin, Masataka; Riffenburgh, Robert H; Tanen, David A

2012-12-01

The objective of this study was to determine the resource utilization of a tertiary care Japanese emergency department (ED) that was not immediately adjacent to the area of the 2011 Great East Japan earthquake and tsunami. A retrospective chart review was performed at a tertiary care university-based urban ED located approximately 290 km from the primary site of destruction secondary to an earthquake measuring 9.0 on the Richter Scale and the resulting tsunami. All patients who presented for a period of twelve days before and twelve days after the disaster were included. Data were collected using preformed data collection sheets, and stored in an Excel file. Abstracted data included gender, time in the ED, intravenous fluid administration, blood transfusion, oxygen, laboratories, electrocardiograms (ECGs), radiographs, ultrasound, diagnoses, surgical and medical referrals, and prescriptions written. Ten percent of the charts were reviewed for accuracy, and an error rate reported. Data were analyzed using 2-tailed t-tests, Fisher's exact tests or rank sum tests. Bonferroni correction was used to adjust P values for multiple comparisons. Charts for 1193 patients were evaluated. The error rate for the abstracted data was 3.2% (95% CI, 2.4%-4.1%). Six hundred fifty-seven patients (53% male) were evaluated in the ED after the earthquake, representing a 23% increase in patient volume. Mean patient time spent in the ED decreased from 61 minutes to 52 minutes (median decrease from 35 minutes to 32 minutes; P = .005). Laboratory utilization decreased from 51% to 43% (P = .006). The percentage of patients receiving prescriptions increased from 48% to 54% (P = .002). There was no change in the number of patients evaluated for surgical complaints, but there was an increase in the number treated for medical or psychiatric complaints. There was a significant increase in the number of people utilizing the ED in Tokyo after the Great East Japan earthquake and tsunami. Time spent

Lifestyle factors and social ties associated with the frequency of laughter after the Great East Japan Earthquake: Fukushima Health Management Survey.

Science.gov (United States)

Hirosaki, Mayumi; Ohira, Tetsuya; Yasumura, Seiji; Maeda, Masaharu; Yabe, Hirooki; Harigane, Mayumi; Takahashi, Hideto; Murakami, Michio; Suzuki, Yuriko; Nakano, Hironori; Zhang, Wen; Uemura, Mayu; Abe, Masafumi; Kamiya, Kenji

2018-03-01

Although mental health problems such as depression after disasters have been reported, positive psychological factors after disasters have not been examined. Recently, the importance of positive affect to our health has been recognised. We therefore investigated the frequency of laughter and its related factors among residents of evacuation zones after the Great East Japan Earthquake of 2011. In a cross-sectional study on 52,320 participants aged 20 years and older who were included in the Fukushima Health Management Survey in Japan's fiscal year 2012, associations of the frequency of laughter with changes in lifestyle after the disaster, such as a changed work situation, the number of family members, and the number of address changes, and other sociodemographic, psychological, and lifestyle factors were examined using logistic regression analysis. The frequency of laughter was assessed using a single-item question: "How often do you laugh out loud?" The proportion of those who laugh almost every day was 27.1%. Multivariable models adjusted for sociodemographic, psychological, and lifestyle factors demonstrated that an increase in the number of family members and fewer changes of address were significantly associated with a high frequency of laughter. Mental health, regular exercise, and participation in recreational activities were also associated with a high frequency of laughter. Changes in lifestyle factors after the disaster were associated with the frequency of laughter in the evacuation zone. Future longitudinal studies are needed to examine what factors can increase the frequency of laughter.

Heart Care in Japan: Before and After the 1995 Great Hanshin-Awaji Earthquake

OpenAIRE

Benedict, Timothy O.

2016-01-01

This paper examines the emergence of the term "heart care (kokoro no kea)" to describe the psychological support for disaster victims in the wake of the 1995 Hanshin earthquake. By comparing the usage of this term in the Yomiuri and Asahi newspapers before and after the earthquake, as well as its relationship with post-traumatic stress disorder (PTSD), this paper will show how heart care emerged in the context of hospice before expanding to include care for trauma more broadly. I will also di...

Possible scenarios for occurrence of M ~ 7 interplate earthquakes prior to and following the 2011 Tohoku-Oki earthquake based on numerical simulation.

Science.gov (United States)

Nakata, Ryoko; Hori, Takane; Hyodo, Mamoru; Ariyoshi, Keisuke

2016-05-10

We show possible scenarios for the occurrence of M ~ 7 interplate earthquakes prior to and following the M ~ 9 earthquake along the Japan Trench, such as the 2011 Tohoku-Oki earthquake. One such M ~ 7 earthquake is so-called the Miyagi-ken-Oki earthquake, for which we conducted numerical simulations of earthquake generation cycles by using realistic three-dimensional (3D) geometry of the subducting Pacific Plate. In a number of scenarios, the time interval between the M ~ 9 earthquake and the subsequent Miyagi-ken-Oki earthquake was equal to or shorter than the average recurrence interval during the later stage of the M ~ 9 earthquake cycle. The scenarios successfully reproduced important characteristics such as the recurrence of M ~ 7 earthquakes, coseismic slip distribution, afterslip distribution, the largest foreshock, and the largest aftershock of the 2011 earthquake. Thus, these results suggest that we should prepare for future M ~ 7 earthquakes in the Miyagi-ken-Oki segment even though this segment recently experienced large coseismic slip in 2011.

Possible scenarios for occurrence of M ~ 7 interplate earthquakes prior to and following the 2011 Tohoku-Oki earthquake based on numerical simulation

Science.gov (United States)

Nakata, Ryoko; Hori, Takane; Hyodo, Mamoru; Ariyoshi, Keisuke

2016-01-01

We show possible scenarios for the occurrence of M ~ 7 interplate earthquakes prior to and following the M ~ 9 earthquake along the Japan Trench, such as the 2011 Tohoku-Oki earthquake. One such M ~ 7 earthquake is so-called the Miyagi-ken-Oki earthquake, for which we conducted numerical simulations of earthquake generation cycles by using realistic three-dimensional (3D) geometry of the subducting Pacific Plate. In a number of scenarios, the time interval between the M ~ 9 earthquake and the subsequent Miyagi-ken-Oki earthquake was equal to or shorter than the average recurrence interval during the later stage of the M ~ 9 earthquake cycle. The scenarios successfully reproduced important characteristics such as the recurrence of M ~ 7 earthquakes, coseismic slip distribution, afterslip distribution, the largest foreshock, and the largest aftershock of the 2011 earthquake. Thus, these results suggest that we should prepare for future M ~ 7 earthquakes in the Miyagi-ken-Oki segment even though this segment recently experienced large coseismic slip in 2011. PMID:27161897

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.

Contributions to the Chile’s Seismic History: the Case of the Great Earthquake of 1730

Directory of Open Access Journals (Sweden)

María X. Urbina Carrasco

2016-12-01

Full Text Available According to the new and previously known documents it is concluded the earthquake of Chile in 1730 was composed by two independent earthquakes, each associated to a tsunami. Considering the latitudinal extension of the damage and the size of the tsunamis, it can be taken as the largest seismic event occurred in the history of Metropolitan or Central Chile. These conclusions allow to know better the seismic sequence of Central Chile, the Seismic History of the country, and contribute to the knowledge of the colonial history of the kingdom of Chile.

2011 Tohoku Earthquake and Japan's Nuclear Disaster - Implications for Indian Ocean Rim countries

Science.gov (United States)

Chadha, R. K.

2011-12-01

The Nuclear disaster in Japan after the M9.0 Tohoku earthquake on March 11, 2011 has elicited global response to have a relook at the safety aspects of the nuclear power plants from all angles including natural hazards like earthquakes and tsunami. Several countries have gone into safety audits of their nuclear programs in view of the experience in Japan. Tectonically speaking, countries located close to subduction zones or in direct line of impact of the subduction zones are the most vulnerable to earthquake or tsunami hazard, as these regions are the locale of great tsunamigenic earthquakes. The Japan disaster has also cautioned to the possibility of great impact to the critical structures along the coasts due to other ocean processes caused by ocean-atmosphere interactions and also due to global warming and sea level rise phenomena in future. This is particular true for island countries. The 2011 Tohoku earthquake in Japan will be remembered more because of its nuclear tragedy and tsunami rather than the earthquake itself. The disaster happened as a direct impact of a tsunami generated by the earthquake 130 km off the coast of Sendai in the Honshu region of Japan. The depth of the earthquake was about 25 km below the ocean floor and it occurred on a thrust fault causing a displacement of more than 20 meters. At few places, water is reported to have inundated areas up to 8-10 km inland. The height of the tsunami varied between 10 and 3 meters along the coast. Generally, during an earthquake damage to buildings or other structures occur due to strong shaking which is expressed in the form of ground accelerations 'g'. Although, Peak Ground Accelerations (PGA) consistently exceeded 2g at several places from Sendai down south, structures at the Fukushima Daiichi Nuclear Power Plant did not collapse due to the earthquake. In the Indian Ocean Rim countries, Indian, Pakistan and South Africa are the three countries where Nuclear power plants are operational, few of them

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.

Earthquake Signal Visible in GRACE Data

Science.gov (United States)

2005-01-01

[figure removed for brevity, see original site] Figure1 This figure shows the effect of the December 2004 great Sumatra earthquake on the Earth's gravity field as observed by GRACE. The signal is expressed in terms of the relative acceleration of the two GRACE satellites, in this case a few nanometers per second squared, or about 1 billionth of the acceleration we experience everyday at the Earth's surface.GRACE observations show comparable signals in the region of the earthquake. Other natural variations are also apparent in the expected places, whereas no other significant change would be expected in the region of the earthquake GRACE, twin satellites launched in March 2002, are making detailed measurements of Earth's gravity field which will lead to discoveries about gravity and Earth's natural systems. These discoveries could have far-reaching benefits to society and the world's population.

Relationships between mental health distress and work-related factors among prefectural public servants two months after the Great East Japan Earthquake.

Science.gov (United States)

Fukasawa, Maiko; Suzuki, Yuriko; Obara, Akiko; Kim, Yoshiharu

2015-02-01

In times of disaster, public servants face multiple burdens as they engage in a demanding and stressful disaster-response work while managing their own needs caused by the disaster. We investigated the effects of work-related factors on the mental health of prefectural public servants working in the area devastated by the Great East Japan Earthquake to identify some ideas for organizational work modifications to protect their mental health. Two months after the earthquake, Miyagi prefecture conducted a self-administered health survey of prefectural public servants and obtained 4,331 (82.8%) valid responses. We investigated relationships between mental health distress (defined as K6 ≥ 13) and work-related variables (i.e., job type, overwork, and working environment) stratified by level of earthquake damage experienced. The proportion of participants with mental health distress was 3.0% in the group that experienced less damage and 5.9% in the group that experienced severe damage. In the group that experienced less damage, working >100 h of overtime per month (adjusted odds ratio [OR], 2.06; 95% confidence interval [CI], 1.11-3.82) and poor workplace communication (adjusted OR, 10.96; 95% CI, 6.63-18.09) increased the risk of mental health distress. In the group that experienced severe damage, handling residents' complaints (adjusted OR, 4.79; 95% CI, 1.55-14.82) and poor workplace communication (adjusted OR, 9.14; 95% CI, 3.34-24.97) increased the risk, whereas involvement in disaster-related work (adjusted OR, 0.39; 95% CI, 0.18-0.86) decreased the risk. Workers who have experienced less disaster-related damage might benefit from working fewer overtime hours, and those who have experienced severe damage might benefit from avoiding contact with residents and engaging in disaster-related work. Facilitating workplace communication appeared important for both groups of workers.

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

KAUST Repository

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

2014-01-01

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

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

KAUST Repository

Goda, Katsuichiro

2014-09-01

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

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

Science.gov (United States)

Heidarzadeh, Mohammad; Ishibe, Takeo; Harada, Tomoya

2018-04-01

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

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...

Coseismic and postseismic deformation associated with the 2016 Mw 7.8 Kaikoura earthquake, New Zealand: fault movement investigation and seismic hazard analysis

Science.gov (United States)

Jiang, Zhongshan; Huang, Dingfa; Yuan, Linguo; Hassan, Abubakr; Zhang, Lupeng; Yang, Zhongrong

2018-04-01

The 2016 moment magnitude (Mw) 7.8 Kaikoura earthquake demonstrated that multiple fault segments can undergo rupture during a single seismic event. Here, we employ Global Positioning System (GPS) observations and geodetic modeling methods to create detailed images of coseismic slip and postseismic afterslip associated with the Kaikoura earthquake. Our optimal geodetic coseismic model suggests that rupture not only occurred on shallow crustal faults but also to some extent at the Hikurangi subduction interface. The GPS-inverted moment release during the earthquake is equivalent to a Mw 7.9 event. The near-field postseismic deformation is mainly derived from right-lateral strike-slip motions on shallow crustal faults. The afterslip did not only significantly extend northeastward on the Needles fault but also appeared at the plate interface, slowly releasing energy over the past 6 months, equivalent to a Mw 7.3 earthquake. Coulomb stress changes induced by coseismic deformation exhibit complex patterns and diversity at different depths, undoubtedly reflecting multi-fault rupture complexity associated with the earthquake. The Coulomb stress can reach several MPa during coseismic deformation, which can explain the trigger mechanisms of afterslip in two high-slip regions and the majority of aftershocks. Based on the deformation characteristics of the Kaikoura earthquake, interseismic plate coverage, and historical earthquakes, we conclude that Wellington is under higher seismic threat after the earthquake and great attention should be paid to potential large earthquake disasters in the near future.[Figure not available: see fulltext.

Time-dependent earthquake probability calculations for southern Kanto after the 2011 M9.0 Tohoku earthquake

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Nanjo, K. Z.; Sakai, S.; Kato, A.; Tsuruoka, H.; Hirata, N.

2013-05-01

Seismicity in southern Kanto activated with the 2011 March 11 Tohoku earthquake of magnitude M9.0, but does this cause a significant difference in the probability of more earthquakes at the present or in the To? future answer this question, we examine the effect of a change in the seismicity rate on the probability of earthquakes. Our data set is from the Japan Meteorological Agency earthquake catalogue, downloaded on 2012 May 30. Our approach is based on time-dependent earthquake probabilistic calculations, often used for aftershock hazard assessment, and are based on two statistical laws: the Gutenberg-Richter (GR) frequency-magnitude law and the Omori-Utsu (OU) aftershock-decay law. We first confirm that the seismicity following a quake of M4 or larger is well modelled by the GR law with b ˜ 1. Then, there is good agreement with the OU law with p ˜ 0.5, which indicates that the slow decay was notably significant. Based on these results, we then calculate the most probable estimates of future M6-7-class events for various periods, all with a starting date of 2012 May 30. The estimates are higher than pre-quake levels if we consider a period of 3-yr duration or shorter. However, for statistics-based forecasting such as this, errors that arise from parameter estimation must be considered. Taking into account the contribution of these errors to the probability calculations, we conclude that any increase in the probability of earthquakes is insignificant. Although we try to avoid overstating the change in probability, our observations combined with results from previous studies support the likelihood that afterslip (fault creep) in southern Kanto will slowly relax a stress step caused by the Tohoku earthquake. This afterslip in turn reminds us of the potential for stress redistribution to the surrounding regions. We note the importance of varying hazards not only in time but also in space to improve the probabilistic seismic hazard assessment for southern Kanto.

[Effects of psychological distress due to the Great East Japan Earthquake, tsunami, Fukushima Nuclear Power Plant disasters on psychiatric symptoms in patients with mental disorders: observational studies in Tochigi].

Science.gov (United States)

Suda, Shiro; Inoue, Koju; Inoue, Kana; Sato, Kazushige; Saito, Harumichi; Matsumoto, Takuya; Suzuki, Yohei; Miyata, Yoshihumi; Kuramochi, Motoki; Kikuchi, Senichiro; Shioda, Katsutoshi; Kobayashi, Toshiyuki; Kishi, Koichiro; Kato, Satoshi

2013-01-01

The Great East Japan Earthquake and subsequent tsunami of March 11, 2011 severely damaged a widespread region of northeastern Japan. Consequently, the Fukushima Nuclear Power Plant experienced a level seven 3 reactors melted down, which released a large amount of radioactive materials into the air. Due to the structural damage and radiation leaks, the victims are facing prolonged psychological distress. Eighty-two subjects with mental disorders who made their initial visit during the first 4 months after the earthquake and one hundred and ninety-four subjects with mental disorders who had been admitted during the first one year after the earthquake to the Jichi Medical University Hospital, which is located at the edge of the disaster-stricken region, were recruited for this study. Enrolled participants were assessed according to ICD-10. A questionnaire survey was employed to evaluate the severity of psychological distress and total amount of damage. The conditions of 22% of the outpatients had been worsened by the psychological distress related to the earthquake. Seven percent of the patients who had been hospitalized showed marked exacerbations due to the psychological distress associated with the disaster. It is of note that the exacerbation of psychiatric symptoms due to the disaster was evident among patients with mental disorders who lived even at the edge of the disaster area (i. e., subject to an earthquake intensity of 5 upper and 150 km from the Fukushima Nuclear Power Plant). The results suggest that the close follow-up of disaster victims with mental disorders is of critical importance.

The USGS Earthquake Notification Service (ENS): Customizable notifications of earthquakes around the globe

Science.gov (United States)

Wald, Lisa A.; Wald, David J.; Schwarz, Stan; Presgrave, Bruce; Earle, Paul S.; Martinez, Eric; Oppenheimer, David

2008-01-01

At the beginning of 2006, the U.S. Geological Survey (USGS) Earthquake Hazards Program (EHP) introduced a new automated Earthquake Notification Service (ENS) to take the place of the National Earthquake Information Center (NEIC) "Bigquake" system and the various other individual EHP e-mail list-servers for separate regions in the United States. These included northern California, southern California, and the central and eastern United States. ENS is a "one-stop shopping" system that allows Internet users to subscribe to flexible and customizable notifications for earthquakes anywhere in the world. The customization capability allows users to define the what (magnitude threshold), the when (day and night thresholds), and the where (specific regions) for their notifications. Customization is achieved by employing a per-user based request profile, allowing the notifications to be tailored for each individual's requirements. Such earthquake-parameter-specific custom delivery was not possible with simple e-mail list-servers. Now that event and user profiles are in a structured query language (SQL) database, additional flexibility is possible. At the time of this writing, ENS had more than 114,000 subscribers, with more than 200,000 separate user profiles. On a typical day, more than 188,000 messages get sent to a variety of widely distributed users for a wide range of earthquake locations and magnitudes. The purpose of this article is to describe how ENS works, highlight the features it offers, and summarize plans for future developments.

Goce derived geoid changes before the Pisagua 2014 earthquake

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Orlando Álvarez

2018-01-01

Full Text Available The analysis of space – time surface deformation during earthquakes reveals the variable state of stress that occurs at deep crustal levels, and this information can be used to better understand the seismic cycle. Understanding the possible mechanisms that produce earthquake precursors is a key issue for earthquake prediction. In the last years, modern geodesy can map the degree of seismic coupling during the interseismic period, as well as the coseismic and postseismic slip for great earthquakes along subduction zones. Earthquakes usually occur due to mass transfer and consequent gravity variations, where these changes have been monitored for intraplate earthquakes by means of terrestrial gravity measurements. When stresses and correspondent rupture areas are large, affecting hundreds of thousands of square kilometres (as occurs in some segments along plate interface zones, satellite gravimetry data become relevant. This is due to the higher spatial resolution of this type of data when compared to terrestrial data, and also due to their homogeneous precision and availability across the whole Earth. Satellite gravity missions as GOCE can map the Earth gravity field with unprecedented precision and resolution. We mapped geoid changes from two GOCE satellite models obtained by the direct approach, which combines data from other gravity missions as GRACE and LAGEOS regarding their best characteristics. The results show that the geoid height diminished from a year to five months before the main seismic event in the region where maximum slip occurred after the Pisagua Mw = 8.2 great megathrust earthquake. This diminution is interpreted as accelerated inland-directed interseismic mass transfer before the earthquake, coinciding with the intermediate degree of seismic coupling reported in the region. We highlight the advantage of satellite data for modelling surficial deformation related to pre-seismic displacements. This deformation, combined to

Meeting the Challenge of Earthquake Risk Globalisation: Towards the Global Earthquake Model GEM (Sergey Soloviev Medal Lecture)

Science.gov (United States)

Zschau, J.

2009-04-01

Earthquake risk, like natural risks in general, has become a highly dynamic and globally interdependent phenomenon. Due to the "urban explosion" in the Third World, an increasingly complex cross linking of critical infrastructure and lifelines in the industrial nations and a growing globalisation of the world's economies, we are presently facing a dramatic increase of our society's vulnerability to earthquakes in practically all seismic regions on our globe. Such fast and global changes cannot be captured with conventional earthquake risk models anymore. The sciences in this field are, therefore, asked to come up with new solutions that are no longer exclusively aiming at the best possible quantification of the present risks but also keep an eye on their changes with time and allow to project these into the future. This does not apply to the vulnerablity component of earthquake risk alone, but also to its hazard component which has been realized to be time-dependent, too. The challenges of earthquake risk dynamics and -globalisation have recently been accepted by the Global Science Forum of the Organisation for Economic Co-operation and Development (OECD - GSF) who initiated the "Global Earthquake Model (GEM)", a public-private partnership for establishing an independent standard to calculate, monitor and communicate earthquake risk globally, raise awareness and promote mitigation.

The Future of Earthquake Relocation Tools

Science.gov (United States)

Lecocq, T.; Caudron, C.

2010-12-01

Many scientists around the world use earthquake relocation software for their research. Some use "known" software like HYPODD or COMPLOC, while others use their own algorithms and codes. Often, beginners struggle to get one tool running or to properly configure input parameters. This Poster will be witness of debates that will take place during the Meeting, for example adressing questions like "Which program for which application?" ; "Standardized In/Outs?" , "Tectonic / Volcanic / Other ?" ; "All programs inside one single Super-Package?" ; "Common/Base Bibliography for the Relocation-Beginner?" ; "Continuous or Layered Velocity Model?" etc... We will also present the scheme of a Super-Package we are working on, grouping HYPODD [Waldhauser 2001], COMPLOC [Lin&Shearer 2006], LOTOS [Koulakov 2009] ; allowing standard in/outs for the 3 programs, and thus, the comparison of their outputs.

THE RESPONSE OF MONTEREY BAY TO THE 2010 CHILEAN EARTHQUAKE

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Laurence C. Breaker

2011-01-01

Full Text Available The primary frequencies contained in the arrival sequence produced by the tsunami from the Chilean earthquake of 2010 in Monterey Bay were extracted to determine the seiche modes that were produced. Singular Spectrum Analysis (SSA and Ensemble Empirical Mode Decomposition (EEMD were employed to extract the primary frequencies of interest. The wave train from the Chilean tsunami lasted for at least four days due to multipath arrivals that may not have included reflections from outside the bay but most likely did include secondary undulations, and energy trapping in the form of edge waves, inside the bay. The SSA decomposition resolved oscillations with periods of 52-57, 34-35, 26-27, and 21-22 minutes, all frequencies that have been predicted and/or observed in previous studies. The EEMD decomposition detected oscillations with periods of 50-55 and 21-22 minutes. Periods in the range of 50-57 minutes varied due to measurement uncertainties but almost certainly correspond to the first longitudinal mode of oscillation for Monterey Bay, periods of 34-35 minutes correspond to the first transverse mode of oscillation that assumes a nodal line across the entrance of the bay, a period of 26- 27 minutes, although previously observed, may not represent a fundamental oscillation, and a period of 21-22 minutes has been predicted and observed previously. A period of ~37 minutes, close to the period of 34-35 minutes, was generated by the Great Alaskan Earthquake of 1964 in Monterey Bay and most likely represents the same mode of oscillation. The tsunamis associated with the Great Alaskan Earthquake and the Chilean Earthquake both entered Monterey Bay but initially arrived outside the bay from opposite directions. Unlike the Great Alaskan Earthquake, however, which excited only one resonant mode inside the bay, the Chilean Earthquake excited several modes suggesting that the asymmetric shape of the entrance to Monterey Bay was an important factor and that the

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.

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

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

Science.gov (United States)

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

2017-12-01

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

Rebuilding Schools after the Wenchuan Earthquake: China Visits OECD, Italy and Turkey

Science.gov (United States)

CELE Exchange, 2009

2009-01-01

As the reconstruction efforts continue in China in the wake of the Great Wenchuan earthquake in May 2008, the China Development Research Foundation, with the support of the OECD Centre for Effective Learning Environments, organised an International Training Programme on the Post-Earthquake Reconstruction of Public Facilities from 1 to 11 December…

Residential relocation and change in social capital: A natural experiment from the 2011 Great East Japan Earthquake and Tsunami.

Science.gov (United States)

Hikichi, Hiroyuki; Sawada, Yasuyuki; Tsuboya, Toru; Aida, Jun; Kondo, Katsunori; Koyama, Shihoko; Kawachi, Ichiro

2017-07-01

Social connections in the community ("social capital") represent an important source of resilience in the aftermath of major disasters. However, little is known about how residential relocation due to housing destruction affects survivors' social capital. We examined changes in social capital among survivors of the 2011 Great East Japan Earthquake and Tsunami. People who lost their homes were resettled to new locations by two primary means: (i) group relocation to public temporary trailer housing or (ii) individual relocation, in which victims moved into government-provided housing by lottery or arranged for their own accommodation (market rental housing or private purchase/new construction). The baseline for our natural experiment was established 7 months before the 11 March 2011 disaster, when we conducted a survey of older community-dwelling adults who lived 80-km west of the earthquake epicenter. Approximately 2.5 years after the disaster, the follow-up survey gathered information about personal experiences of disaster as well as health status and social capital. Among 3421 people in our study, 79 people moved via group relocation to public temporary trailer housing, whereas 96 people moved on their own. The individual fixed-effects model showed that group relocation was associated with improved informal socializing and social participation (β coefficient = 0.053, 95% confidence interval: 0.011 to 0.095). In contrast, individual relocation was associated with declining informal socializing and social participation (β coefficient = -0.039, 95% confidence interval: -0.074 to -0.003). Group relocation, as compared to individual relocation, appeared to preserve social participation and informal socializing in the community.

The Great East Japan Earthquake, tsunami, and Fukushima Daiichi nuclear power plant accident: a triple disaster affecting the mental health of the country.

Science.gov (United States)

Yamashita, Jun; Shigemura, Jun

2013-09-01

The Great East Japan Earthquake in 2011 caused 2 other serious disasters: a tsunami and a nuclear power plant accident. A chronic shortage of mental health resources had been previously reported in the Tohoku region, and the triple disaster worsened the situation. Eventually a public health approach was implemented by providing a common room in temporary housing developments to build a sense of community and to approach evacuees so that they could be triaged and referred to mental health teams. Japan now advocates using psychological first aid to educate first responders. This article extracts key lessons from relevant literature. Copyright © 2013 Elsevier Inc. All rights reserved.

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

Science.gov (United States)

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

2016-01-01

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

Investigating Earthquake-induced Landslides­a Historical Review

Science.gov (United States)

Keefer, D. K.; Geological Survey, Us; Park, Menlo; Usa, Ca

Although earthquake-induced landslides have been described in documents for more than 3700 years, accounts from earthquakes before the late eighteenth century are incomplete concerning landslide numbers and vague concerning landslide character- istics. They are thus typically misleading concerning the true abundance of landslides and range of landslide characteristics. Beginning with studies of the 1783 Calabria, Italy earthquake, more complete and precise data concerning the occurrence of land- slides in earthquakes have become available. The historical development of knowl- edge concerning landslides triggered by earthquakes can be divided into several peri- ods. The first period, from 1783 until the first application of aerial photography, was characterized by ground-based studies of earthquake effects, typically carried out by formal scientific commissions. These formal studies typically identified a large, but not necessarily comprehensive, sampling of localities where landslides had occurred. In some, but not all cases, landslide characteristics were also described in enough de- tail that the general range of landslide characteristics could begin to be determined. More recently, some nineteenth to mid-twentieth century earthquakes have been stud- ied using retrospective analyses, in which the landslide occurrences associated with the event are inferred years to decades later, using contemporary accounts, mapping from aerial photographs, statistical studies, and (or) geotechnical analyses. The first use of aerial photographs to map earthquake effects immediately after the event prob- ably occurred in 1948. Since that time, the use of aerial photography has greatly facil- itated the compilation of post-earthquake landslide inventories, although because of the limitations of aerial photography, ground-based field studies continue to be cru- cial in preparing accurate and comprehensive landslide maps. Beginning with a small California earthquake in 1957

Remote Triggering of the Mw 6.9 Hokkaido Earthquake as a Result of the Mw 6.6 Indonesian Earthquake on September 11, 2008

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Cheng-Horng Lin

2012-01-01

Full Text Available Only just recently, the phenomenon of earthquakes being triggered by a distant earthquake has been well established. Yet, most of the triggered earthquakes have been limited to small earthquakes (M < 3. Also, the exact triggering mechanism for earthquakes is still not clear. Here I show how one strong earthquake (Mw = 6.6 is capable of triggering another (Mw = 6.9 at a remote distance (~4750 km. On September 11, 2008, two strong earthquakes with magnitudes (Mw of 6.6 and 6.9 hit respectively in Indonesia and Japan within a short interval of ~21 minutes time. Careful examination of broadband seismograms recorded in Japan shows that the Hokkaido earthquake occurred just as the surface waves generated by the Indonesia earthquake arrived. Although the peak dynamic stress estimated at the focus of the Hokkaido earthquake was just reaching the lower bound for the capability of triggering earthquakes in general, a more plausible mechanism for triggering an earthquake might be attributed to the change of a fault property by fluid infiltration. These observations suggest that the Hokkaido earthquake was likely triggered from a remote distance by the surface waves generated from the Indonesia earthquake. If some more cases can be observed, a temporal warning of possible interaction between strong earthquakes might be concerned in the future.

The Role of Museums in Recovery From Disaster: The Great East Japan Earthquake and Tsunami

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Sudo Ken‘ichi

2014-12-01

in the wake of the Great East Japan Earthquake demonstrates that a museum’s efforts to revive and restore traditional performing arts can do more than sustain folk arts. It can also play a vital role in rebuilding the spirits of communities and localities affected by disasters.

Remarkable changes in behavior and physiology of laboratory mice after the massive 2011 Tohoku earthquake in Japan.

Science.gov (United States)

Yanai, Shuichi; Semba, Yuki; Endo, Shogo

2012-01-01

A devastating earthquake and tsunami hit Japan on March 11, 2011, followed by several long and intense aftershocks. Laboratory mice housed in the Tokyo, located approximately 330 km south of this earthquake's epicenter, displayed remarkable changes in a variety of behaviors and physiological measures. Although unusual pre-earthquake behaviors have been previously reported in laboratory animals, little is known about behavioral and physiological changes that occur after a great earthquake. In the present study, the effects of Tohoku earthquake on mice behavior were investigated. "Earthquake-experienced" mice displayed a marked increase in food consumption without gaining body weight in response to the earthquake. They also displayed enhanced anxiety, and in a formal fear memory task, showed significantly greater tone- and context-dependent conditioned freezing. Water maze performance of earthquake-experienced mice showed the quicker acquisition of the task, faster swim speed and longer swim distance than the naive mice. Serum corticosterone levels were elevated compared to the naive mice, indicating that the earthquake and aftershocks were stressful for the mice. These results demonstrate that great earthquakes strongly affect mouse behaviors and physiology. Although the effects of a variety of experimental manipulations on mouse behaviors in disease models or in models of higher cognitive functions have been extensively examined, researchers need to be aware how natural phenomena, such as earthquakes and perhaps other natural environmental factors, influence laboratory animal behaviors and physiology.

Earthquake risk assessment of building structures

International Nuclear Information System (INIS)

Ellingwood, Bruce R.

2001-01-01

During the past two decades, probabilistic risk analysis tools have been applied to assess the performance of new and existing building structural systems. Structural design and evaluation of buildings and other facilities with regard to their ability to withstand the effects of earthquakes requires special considerations that are not normally a part of such evaluations for other occupancy, service and environmental loads. This paper reviews some of these special considerations, specifically as they pertain to probability-based codified design and reliability-based condition assessment of existing buildings. Difficulties experienced in implementing probability-based limit states design criteria for earthquake are summarized. Comparisons of predicted and observed building damage highlight the limitations of using current deterministic approaches for post-earthquake building condition assessment. The importance of inherent randomness and modeling uncertainty in forecasting building performance is examined through a building fragility assessment of a steel frame with welded connections that was damaged during the Northridge Earthquake of 1994. The prospects for future improvements in earthquake-resistant design procedures based on a more rational probability-based treatment of uncertainty are examined

Sector model analysis of risk on cross-jurisdictional treatment of disaster waste related to the Great East Japan Earthquake

International Nuclear Information System (INIS)

Nagashima, Miori; Itokawa, Etsuko; Ozuka, Yohei

2012-01-01

This study addressed the controversial issue of disaster waste treatment in the reconstruction efforts following the Great East Japan Earthquake. Using the Sector Model (Matsumoto 2009), we categorized a range of actions taken in relation to the cross-jurisdictional treatment into the four sectors, government, industry, academia, and private. The analysis through this Sector Model made it possible to map the entire layout of waste treatment, inclusive of less-visible industry and academia sectors. Accordingly, we have argued that differences of risk awareness are not necessarily due to sector differences but rather depend on two aspects of the disaster waste treatment; the safety levels and the nationwide treatment of waste in Japan. We further suggest that the discrepancy in the arguments on safety levels emerged as a result of scientific under-determination and cross-jurisdictional treatment from social and/or political under-determination. (author)

Future of Earthquake Early Warning: Quantifying Uncertainty and Making Fast Automated Decisions for Applications

Science.gov (United States)

Wu, Stephen

Earthquake early warning (EEW) systems have been rapidly developing over the past decade. Japan Meteorological Agency (JMA) has an EEW system that was operating during the 2011 M9 Tohoku earthquake in Japan, and this increased the awareness of EEW systems around the world. While longer-time earthquake prediction still faces many challenges to be practical, the availability of shorter-time EEW opens up a new door for earthquake loss mitigation. After an earthquake fault begins rupturing, an EEW system utilizes the first few seconds of recorded seismic waveform data to quickly predict the hypocenter location, magnitude, origin time and the expected shaking intensity level around the region. This early warning information is broadcast to different sites before the strong shaking arrives. The warning lead time of such a system is short, typically a few seconds to a minute or so, and the information is uncertain. These factors limit human intervention to activate mitigation actions and this must be addressed for engineering applications of EEW. This study applies a Bayesian probabilistic approach along with machine learning techniques and decision theories from economics to improve different aspects of EEW operation, including extending it to engineering applications. Existing EEW systems are often based on a deterministic approach. Often, they assume that only a single event occurs within a short period of time, which led to many false alarms after the Tohoku earthquake in Japan. This study develops a probability-based EEW algorithm based on an existing deterministic model to extend the EEW system to the case of concurrent events, which are often observed during the aftershock sequence after a large earthquake. To overcome the challenge of uncertain information and short lead time of EEW, this study also develops an earthquake probability-based automated decision-making (ePAD) framework to make robust decision for EEW mitigation applications. A cost-benefit model that

Geomagnetic anomalies - possible earthquake precursors - linked with 2004 significant seismic activity in Vrancea, Romania

International Nuclear Information System (INIS)

Enescu, D.

2005-01-01

The association between a precursory geomagnetic anomaly and a Vrancea earthquake of moderate-to-high magnitude (M W = 6.3) followed by weaker earthquakes (M W W ≤ 6.3 the conclusion of our earlier papers, i.e., that the great majority of Vrancea earthquakes of magnitudes 3.7 ≤ M W ≤5.0 were accompanied by observable precursory electromagnetic anomalies. Our works show that neither the precursor time nor the amplitude of the precursory magnetic anomaly can be linked reliably with the magnitude of the anticipated earthquake. Knowing the way electric resistivity varies ahead of an earthquake, we can assert that the earthquake-precursory growth in geomagnetic impedance is matched by an earthquake-precursory decrease of electric resistivity. (authors)

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...

Disease prevalence among nursery school children after the Great East Japan earthquake.

Science.gov (United States)

Ishikuro, Mami; Matsubara, Hiroko; Kikuya, Masahiro; Obara, Taku; Sato, Yuki; Metoki, Hirohito; Isojima, Tsuyoshi; Yokoya, Susumu; Kato, Noriko; Tanaka, Toshiaki; Chida, Shoichi; Ono, Atsushi; Hosoya, Mitsuaki; Yokomichi, Hiroshi; Yamagata, Zentaro; Tanaka, Soichiro; Kure, Shigeo; Kuriyama, Shinichi

2017-01-01

To investigate the relationship between personal experience of the Great East Japan Earthquake and various disease types among nursery school children. We conducted a nationwide survey of nursery school children born between 2 April 2006 and 1 April 2007. Nursery school teachers completed questionnaires if they agreed to join the study. Questionnaire items for children consisted of their birth year and month, sex, any history of moving into or out of the current nursery school, presence of diseases diagnosed by a physician at the age of 66-78 months and type of disaster experience. The survey was conducted from September 2012 to December 2012. Japan, nationwide. A total of 60 270 nursery school children were included in the analysis, 840 of whom experienced the disaster on 11 March 2011. The health status of children 1.5 years after the disaster based on nursery school records. Experiencing the disaster significantly affected the prevalence of overall and individual diseases. Furthermore, there was a difference in disease prevalence between boys and girls. In boys, experiencing the tsunami (OR 2.53, 95% CI 1.22 to 5.24) and living in an evacuation centre (OR 2.92, 95% CI 1.46 to 5.83) were remarkably associated with a higher prevalence of atopic dermatitis, but these trends were not observed among girls. Instead, the home being destroyed (OR 3.50, 95% CI 2.02 to 6.07) and moving house (OR 4.19, 95% CI 2.01 to 8.71) were positively associated with a higher prevalence of asthma among girls. Our study indicates that experiencing the disaster may have affected the health status of nursery school children at least up to 1.5 years after the disaster. Continuous monitoring of the health status of children is necessary to develop strategic plans for child health.

Fault Branching and Long-Term Earthquake Rupture Scenario for Strike-Slip Earthquake

Science.gov (United States)

Klinger, Y.; CHOI, J. H.; Vallage, A.

2017-12-01

Careful examination of surface rupture for large continental strike-slip earthquakes reveals that for the majority of earthquakes, at least one major branch is involved in the rupture pattern. Often, branching might be either related to the location of the epicenter or located toward the end of the rupture, and possibly related to the stopping of the rupture. In this work, we examine large continental earthquakes that show significant branches at different scales and for which ground surface rupture has been mapped in great details. In each case, rupture conditions are described, including dynamic parameters, past earthquakes history, and regional stress orientation, to see if the dynamic stress field would a priori favor branching. In one case we show that rupture propagation and branching are directly impacted by preexisting geological structures. These structures serve as pathways for the rupture attempting to propagate out of its shear plane. At larger scale, we show that in some cases, rupturing a branch might be systematic, hampering possibilities for the development of a larger seismic rupture. Long-term geomorphology hints at the existence of a strong asperity in the zone where the rupture branched off the main fault. There, no evidence of throughgoing rupture could be seen along the main fault, while the branch is well connected to the main fault. This set of observations suggests that for specific configurations, some rupture scenarios involving systematic branching are more likely than others.

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.

Co-Seismic Gravity Gradient Changes of the 2006-2007 Great Earthquakes in the Central Kuril Islands from GRACE Observations

Science.gov (United States)

Rahimi, A.; Shahrisvand, M.

2017-09-01

GRACE satellites (the Gravity Recovery And climate Experiment) are very useful sensors to extract gravity anomalies after earthquakes. In this study, we reveal co-seismic signals of the two combined earthquakes, the 2006 Mw8.3 thrust and 2007 Mw8.1 normal fault earthquakes of the central Kuril Islands from GRACE observations. We compute monthly full gravitational gradient tensor in the local north-east-down frame for Kuril Islands earthquakes without spatial averaging and de-striping filters. Some of gravitational gradient components (e.g. ΔVxx, ΔVxz) enhance high frequency components of the earth gravity field and reveal more details in spatial and temporal domain. Therefore, co-seismic activity can be better illustrated. For the first time, we show that the positive-negative-positive co-seismic ΔVxx due to the Kuril Islands earthquakes ranges from - 0.13 to + 0.11 milli Eötvös, and ΔVxz shows a positive-negative-positive pattern ranges from - 0.16 to + 0.13 milli Eötvös, agree well with seismic model predictions.

Why Different Drought Indexes Show Distinct Future Drought Risk Outcomes in the U.S. Great Plains?

Science.gov (United States)

Feng, S.; Hayes, M. J.; Trnka, M.

2015-12-01

Vigorous discussions and disagreements about the future changes in drought intensity in the US Great Plains have been taking place recently within the literature. These discussions have involved widely varying estimates based on drought indices and model-based projections of the future. To investigate and understand the causes for such a disparity between these previous estimates, we analyzed 10 commonly-used drought indexes using the output from 26 state-of-the-art climate models. These drought indices were computed using potential evapotranspiration estimated by the physically-based Penman-Monteith method (PE_pm) and the empirically-based Thornthwaite method (PE_th). The results showed that the short-term drought indicators are similar to modeled surface soil moisture and show a small but consistent drying trend in the future. The long-term drought indicators and the total column soil moisture, however, are consistent in projecting more intense future drought. When normalized, the drought indices with PE_th all show unprecedented and possibly unrealistic future drying, while the drought indices with PE_pm show comparable dryness with the modeled soil moisture. Additionally, the drought indices with PE_pm are closely related to soil moisture during both the 20th and 21st Centuries. Overall, the drought indices with PE_pm, as well as the modeled total column soil moisture, suggest a widespread and very significant drying of the Great Plains region toward the end of the Century. Our results suggested that the sharp contracts about future drought risk in the Great Plains discussed in previous studies are caused by 1) comparing the projected changes in short-term droughts with that of the long-term droughts, and/or 2) computing the atmospheric evaporative demand using the empirically-based method (e.g., PE_th). Our analysis may be applied for drought projections in other regions across the globe.

[The number of deaths by suicide after the Great East Japan Earthquake based on demographic statistics in the coastal and non-coastal areas of Iwate, Miyagi, and Fukushima prefectures].

Science.gov (United States)

Masaki, Naoko; Hashimoto, Shuji; Kawado, Miyuki; Ojima, Toshiyuki; Takeshima, Tadashi; Matsubara, Miyuki; Mitoku, Kazuko; Ogata, Yukiko

2018-01-01

Objective　The number of deaths by suicide after the Great East Japan Earthquake was surveyed based on demographic statistics. In particular, this study examined whether or not there were excessive deaths due to suicide (excluding people who were injured in the earthquake) after the Great East Japan Earthquake disaster. This examination surveyed municipalities in coastal and non-coastal areas of Iwate, Miyagi, and Fukushima prefectures (referred to below as the "three prefectures").Methods　The demographic statistics questionnaire survey information supplied by Article 33 of the Statistics Act (Ministry of Health, Labour and Welfare's published statistics Vol. 0925 No.4, September 25 th , 2014) were used as the basic data with particular reference to the information on the deaths from January 1 st , 2010 to March 31 st , 2013. The information obtained included the date of death, the municipality where the address of the deceased was registered, the gender of the deceased, age at the time of death, and cause of death codes (International Classification of Disease Codes 10 th revision: ICD-10). Additionally, information was gathered about the population based on the resident register from 2009 to 2013 and the 2010 National Census; the number of deaths by suicide was then totalled by period and area. The areas were classified as municipalities within three prefectures and those located elsewhere using the municipality where the address of the deceased was registered.Results　The SMR for suicides did not show a tendency to increase for coastal or non-coastal areas throughout the two-year period after the earthquake disaster (from March 2011 to February 2013).　The SMR for the three prefectures 0-1 years after the disaster compared with the year before the disaster was 0.92 and for 1-2 years after the disaster was 0.93. Both these values were significantly low. Looking at both the non-coastal and coastal areas from each of the three prefectures, the SMR for suicides

Earthquake source imaging by high-resolution array analysis at regional distances: the 2010 M7 Haiti earthquake as seen by the Venezuela National Seismic Network

Science.gov (United States)

Meng, L.; Ampuero, J. P.; Rendon, H.

2010-12-01

Back projection of teleseismic waves based on array processing has become a popular technique for earthquake source imaging,in particular to track the areas of the source that generate the strongest high frequency radiation. The technique has been previously applied to study the rupture process of the Sumatra earthquake and the supershear rupture of the Kunlun earthquakes. Here we attempt to image the Haiti earthquake using the data recorded by Venezuela National Seismic Network (VNSN). The network is composed of 22 broad-band stations with an East-West oriented geometry, and is located approximately 10 degrees away from Haiti in the perpendicular direction to the Enriquillo fault strike. This is the first opportunity to exploit the privileged position of the VNSN to study large earthquake ruptures in the Caribbean region. This is also a great opportunity to explore the back projection scheme of the crustal Pn phase at regional distances,which provides unique complementary insights to the teleseismic source inversions. The challenge in the analysis of the 2010 M7.0 Haiti earthquake is its very compact source region, possibly shorter than 30km, which is below the resolution limit of standard back projection techniques based on beamforming. Results of back projection analysis using the teleseismic USarray data reveal little details of the rupture process. To overcome the classical resolution limit we explored the Multiple Signal Classification method (MUSIC), a high-resolution array processing technique based on the signal-noise orthognality in the eigen space of the data covariance, which achieves both enhanced resolution and better ability to resolve closely spaced sources. We experiment with various synthetic earthquake scenarios to test the resolution. We find that MUSIC provides at least 3 times higher resolution than beamforming. We also study the inherent bias due to the interferences of coherent Green’s functions, which leads to a potential quantification

The 2008 Wenchuan Earthquake and the Rise and Fall of Earthquake Prediction in China

Science.gov (United States)

Chen, Q.; Wang, K.

2009-12-01

Regardless of the future potential of earthquake prediction, it is presently impractical to rely on it to mitigate earthquake disasters. The practical approach is to strengthen the resilience of our built environment to earthquakes based on hazard assessment. But this was not common understanding in China when the M 7.9 Wenchuan earthquake struck the Sichuan Province on 12 May 2008, claiming over 80,000 lives. In China, earthquake prediction is a government-sanctioned and law-regulated measure of disaster prevention. A sudden boom of the earthquake prediction program in 1966-1976 coincided with a succession of nine M > 7 damaging earthquakes in the densely populated region of the country and the political chaos of the Cultural Revolution. It climaxed with the prediction of the 1975 Haicheng earthquake, which was due mainly to an unusually pronounced foreshock sequence and the extraordinary readiness of some local officials to issue imminent warning and evacuation order. The Haicheng prediction was a success in practice and yielded useful lessons, but the experience cannot be applied to most other earthquakes and cultural environments. Since the disastrous Tangshan earthquake in 1976 that killed over 240,000 people, there have been two opposite trends in China: decreasing confidence in prediction and increasing emphasis on regulating construction design for earthquake resilience. In 1976, most of the seismic intensity XI areas of Tangshan were literally razed to the ground, but in 2008, many buildings in the intensity XI areas of Wenchuan did not collapse. Prediction did not save life in either of these events; the difference was made by construction standards. For regular buildings, there was no seismic design in Tangshan to resist any earthquake shaking in 1976, but limited seismic design was required for the Wenchuan area in 2008. Although the construction standards were later recognized to be too low, those buildings that met the standards suffered much less

Change in failure stress on the southern san andreas fault system caused by the 1992 magnitude = 7.4 landers earthquake.

Science.gov (United States)

Stein, R S; King, G C; Lin, J

1992-11-20

The 28 June Landers earthquake brought the San Andreas fault significantly closer to failure near San Bernardino, a site that has not sustained a large shock since 1812. Stress also increased on the San Jacinto fault near San Bernardino and on the San Andreas fault southeast of Palm Springs. Unless creep or moderate earthquakes relieve these stress changes, the next great earthquake on the southern San Andreas fault is likely to be advanced by one to two decades. In contrast, stress on the San Andreas north of Los Angeles dropped, potentially delaying the next great earthquake there by 2 to 10 years.

Earthquake stand-by instruction device for nuclear power plant

International Nuclear Information System (INIS)

Nakagawa, Masaki; Ijima, Tadashi

1998-01-01

The magnitude of earthquakes is forecast at a high accuracy by disposing seismic detectors to a plurality of points distant from an object plant. The accuracy of the judgement for the magnitude of earthquakes can be improved by processing seismic movements by using seismic movements observed along with elapse of time. The measured seismic waveforms are always stored even during the processing time. With such procedures, when one processing is completed, processing can be conducted successively by using stored data, by which processing can be conducted by using all the data from the occurrence of the earthquakes. Then, the seismic movements can be estimated from an early stage of the occurrence of the earthquakes, and since the seismic movement can be judged based on a great amount of data with lapse of time, an appropriate stand-by instruction can be provided. (N.H.)

Health Outcomes for Children in Haiti Since the 2010 Earthquake: A Systematic Review.

Science.gov (United States)

Dube, Annie; Moffatt, Madeline; Davison, Colleen; Bartels, Susan

2018-02-01

Haiti remains the poorest country in the Americas and one of the poorest in the world. Children in Haiti face many health concerns, some of which were exacerbated by the 2010 earthquake. This systematic review summarizes published research conducted since the 2010 earthquake, focusing on health outcomes for children in Haiti, including physical, psychological, and socioeconomic well-being. A literature search was conducted identifying articles published from January 2010 through May 2016 related to pediatric health outcomes in Haiti. Two reviewers screened articles independently. Included research articles described at least one physical health, psychological health, or socioeconomic outcome among children less than 18 years of age in Haiti since the January 2010 earthquake. Fifty-eight full-length research articles were reviewed, covering infectious diseases (non-cholera [N=12] and cholera [N=7]), nutrition (N=11), traumatic injuries (N=11), mental health (N=9), anemia (N=4), abuse and violence (N=5), and other topics (N=3). Many children were injured in the 2010 earthquake, and care of their injuries is described in the literature. Infectious diseases were a significant cause of morbidity and mortality among children following the earthquake, with cholera being one of the most important etiologies. The literature also revealed that large numbers of children in Haiti have significant symptoms of posttraumatic stress disorder (PTSD), peri-traumatic stress, depression, and anxiety, and that food insecurity and malnutrition continue to be important issues. Future health programs in Haiti should focus on provision of clean water, sanitation, and other measures to prevent infectious diseases. Mental health programming and services for children also appear to be greatly needed, and food insecurity/malnutrition must be addressed if children are to lead healthy, productive lives. Given the burden of injury after the 2010 earthquake, further research on long

Trends in psychological distress and alcoholism after The Great East Japan Earthquake of 2011

Directory of Open Access Journals (Sweden)

A. Kanehara

2016-12-01

Full Text Available Aims: Many studies have shown that natural disasters affect mental health; however, longitudinal data on post-disaster mental health problems are scarce. The aims of our study were to investigate the trend in psychological distress and alcoholism after The Great East Japan Earthquake and tsunami in north eastern Japan, in March 2011. Methods: A longitudinal study was conducted using annual health check data for the general population, in the city of Higashi-Matsushima, which was affected by the high impact of tsunami. In 2012 and 2013, the Kessler Psychological Distress Scale and the CAGE questionnaire (for screening for alcoholism were used to assess psychological distress and prevalence of alcoholism. Results: Of 11,855 total eligible residents, 2192 received the annual check in 2012 and 2013. The prevalence of mental illness and the mean score of alcoholism tendency increased during the follow-up period. The majority of respondents (43.8% with baseline serious mental illness (SMI continued to have SMI at follow-up; only 16.7% reported recovering. Older age, female sex, and severity of home damage predicted higher psychological distress, while male sex was a risk factor for alcoholism at follow-up. Conclusions: Psychological distress deteriorated 2 years after the huge natural disaster, compared with 1 year after the disaster. Long-term mental health care is needed for those affected by natural disasters, particularly those who have suffered loss. Keywords: Natural disaster, Psychological distress, Alcoholism, Longitudinal study

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. .

Earthquake geology of the Bulnay Fault (Mongolia)

Science.gov (United States)

Rizza, Magali; Ritz, Jean-Franciois; Prentice, Carol S.; Vassallo, Ricardo; Braucher, Regis; Larroque, Christophe; Arzhannikova, A.; Arzhanikov, S.; Mahan, Shannon; Massault, M.; Michelot, J-L.; Todbileg, M.

2015-01-01

The Bulnay earthquake of July 23, 1905 (Mw 8.3-8.5), in north-central Mongolia, is one of the world's largest recorded intracontinental earthquakes and one of four great earthquakes that occurred in the region during the 20th century. The 375-km-long surface rupture of the left-lateral, strike-slip, N095°E trending Bulnay Fault associated with this earthquake is remarkable for its pronounced expression across the landscape and for the size of features produced by previous earthquakes. Our field observations suggest that in many areas the width and geometry of the rupture zone is the result of repeated earthquakes; however, in those areas where it is possible to determine that the geomorphic features are the result of the 1905 surface rupture alone, the size of the features produced by this single earthquake are singular in comparison to most other historical strike-slip surface ruptures worldwide. Along the 80 km stretch, between 97.18°E and 98.33°E, the fault zone is characterized by several meters width and the mean left-lateral 1905 offset is 8.9 ± 0.6 m with two measured cumulative offsets that are twice the 1905 slip. These observations suggest that the displacement produced during the penultimate event was similar to the 1905 slip. Morphotectonic analyses carried out at three sites along the eastern part of the Bulnay fault, allow us to estimate a mean horizontal slip rate of 3.1 ± 1.7 mm/yr over the Late Pleistocene-Holocene period. In parallel, paleoseismological investigations show evidence for two earthquakes prior to the 1905 event with recurrence intervals of ~2700-4000 years.

Earthquake-proof supporting structure in reactor vessel

International Nuclear Information System (INIS)

Sakurai, Akio; Sekine, Katsuhisa; Madokoro, Manabu; Katoono, Shin-ichi; Konno, Mutsuo; Suzuki, Takuro.

1990-01-01

Conventional earthquake-proof structure comprises a vessel vibration stopper integrated to a reactor vessel, powder for restricting the horizontal displacements, a safety vessel surrounds the outer periphery of the reactor vessel and a safety vessel vibration stopper integrated therewith, which are fixed to buildings. However, there was a problem that a great amount of stresses are generated in the base of the reactor vessel vibration stopper due to reaction of the powders which restrict thermal expansion. In order to remarkably reduce the reaction of the powers, powders are charged into a spaces formed between each of the reactor vessel vibration stopper, the safety vessel vibration stopper and the flexible member disposed between them. According to this constitution, the reactor vessel vibration stopper does not undergo a great reaction of the powers upon thermal expansion of the reactor vessel to moderate the generated stresses, maintain the strength and provide earthquake-proof supporting function. (N.H.)

Remarkable changes in behavior and physiology of laboratory mice after the massive 2011 Tohoku earthquake in Japan.

Directory of Open Access Journals (Sweden)

Shuichi Yanai

Full Text Available A devastating earthquake and tsunami hit Japan on March 11, 2011, followed by several long and intense aftershocks. Laboratory mice housed in the Tokyo, located approximately 330 km south of this earthquake's epicenter, displayed remarkable changes in a variety of behaviors and physiological measures. Although unusual pre-earthquake behaviors have been previously reported in laboratory animals, little is known about behavioral and physiological changes that occur after a great earthquake. In the present study, the effects of Tohoku earthquake on mice behavior were investigated. "Earthquake-experienced" mice displayed a marked increase in food consumption without gaining body weight in response to the earthquake. They also displayed enhanced anxiety, and in a formal fear memory task, showed significantly greater tone- and context-dependent conditioned freezing. Water maze performance of earthquake-experienced mice showed the quicker acquisition of the task, faster swim speed and longer swim distance than the naive mice. Serum corticosterone levels were elevated compared to the naive mice, indicating that the earthquake and aftershocks were stressful for the mice. These results demonstrate that great earthquakes strongly affect mouse behaviors and physiology. Although the effects of a variety of experimental manipulations on mouse behaviors in disease models or in models of higher cognitive functions have been extensively examined, researchers need to be aware how natural phenomena, such as earthquakes and perhaps other natural environmental factors, influence laboratory animal behaviors and physiology.

Earthquake Loss Scenarios: Warnings about the Extent of Disasters

Science.gov (United States)

Wyss, M.; Tolis, S.; Rosset, P.

2016-12-01

It is imperative that losses expected due to future earthquakes be estimated. Officials and the public need to be aware of what disaster is likely in store for them in order to reduce the fatalities and efficiently help the injured. Scenarios for earthquake parameters can be constructed to a reasonable accuracy in highly active earthquake belts, based on knowledge of seismotectonics and history. Because of the inherent uncertainties of loss estimates however, it would be desirable that more than one group calculate an estimate for the same area. By discussing these estimates, one may find a consensus of the range of the potential disasters and persuade officials and residents of the reality of the earthquake threat. To model a scenario and estimate earthquake losses requires data sets that are sufficiently accurate of the number of people present, the built environment, and if possible the transmission of seismic waves. As examples we use loss estimates for possible repeats of historic earthquakes in Greece that occurred between -464 and 700. We model future large Greek earthquakes as having M6.8 and rupture lengths of 60 km. In four locations where historic earthquakes with serious losses have occurred, we estimate that 1,000 to 1,500 people might perish, with an additional factor of four people injured. Defining the area of influence of these earthquakes as that with shaking intensities larger and equal to V, we estimate that 1.0 to 2.2 million people in about 2,000 settlements may be affected. We calibrate the QLARM tool for calculating intensities and losses in Greece, using the M6, 1999 Athens earthquake and matching the isoseismal information for six earthquakes, which occurred in Greece during the last 140 years. Comparing fatality numbers that would occur theoretically today with the numbers reported, and correcting for the increase in population, we estimate that the improvement of the building stock has reduced the mortality and injury rate in Greek

Preliminary Study on Earthquake Surface Rupture Extraction from Uav Images

Science.gov (United States)

Yuan, X.; Wang, X.; Ding, X.; Wu, X.; Dou, A.; Wang, S.

2018-04-01

Because of the advantages of low-cost, lightweight and photography under the cloud, UAVs have been widely used in the field of seismic geomorphology research in recent years. Earthquake surface rupture is a typical seismic tectonic geomorphology that reflects the dynamic and kinematic characteristics of crustal movement. The quick identification of earthquake surface rupture is of great significance for understanding the mechanism of earthquake occurrence, disasters distribution and scale. Using integrated differential UAV platform, series images were acquired with accuracy POS around the former urban area (Qushan town) of Beichuan County as the area stricken seriously by the 2008 Wenchuan Ms8.0 earthquake. Based on the multi-view 3D reconstruction technique, the high resolution DSM and DOM are obtained from differential UAV images. Through the shade-relief map and aspect map derived from DSM, the earthquake surface rupture is extracted and analyzed. The results show that the surface rupture can still be identified by using the UAV images although the time of earthquake elapse is longer, whose middle segment is characterized by vertical movement caused by compression deformation from fault planes.

Current status of JRR-3. After the 3.11 earthquake

International Nuclear Information System (INIS)

Arai, Masaji; Murayama, Yoji; Wada, Shigeru

2012-01-01

JRR-3 at Tokai site of JAEA was in its regular maintenance period, when the Great East Japan Earthquake was taken place on 11th March 2011. The reactor building with their solid foundations and the equipment important to safety survived the earthquake without serious damage and no radioactive leakage has been occurred. Recovery work is planned to be completed by the end of this March. At the same time, check and test of the integrity of all components and seismic assessment to show resistance with the 3.11 earthquake have been carried out. JRR-3 will restart its operation after completing above mentioned procedures. (author)

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.

Survey of Preventable Disaster Deaths at Medical Institutions in Areas Affected by the Great East Japan Earthquake: Retrospective Survey of Medical Institutions in Miyagi Prefecture.

Science.gov (United States)

Yamanouchi, Satoshi; Sasaki, Hiroyuki; Kondo, Hisayoshi; Mase, Tomohiko; Otomo, Yasuhiro; Koido, Yuichi; Kushimoto, Shigeki

2017-10-01

Introduction In 2015, the authors reported the results of a preliminary investigation of preventable disaster deaths (PDDs) at medical institutions in areas affected by the Great East Japan Earthquake (2011). This initial survey considered only disaster base hospitals (DBHs) and hospitals that had experienced at least 20 patient deaths in Miyagi Prefecture (Japan); therefore, hospitals that experienced fewer than 20 patient deaths were not investigated. This was an additional study to the previous survey to better reflect PDD at hospitals across the entire prefecture. Of the 147 hospitals in Miyagi Prefecture, the 14 DBHs and 82 non-DBHs that agreed to participate were included in an on-site survey. A database was created based on the medical records of 1,243 patient deaths that occurred between March 11, 2011 and April 1, 2011, followed by determination of their status as PDDs. A total of 125 cases of PDD were identified among the patients surveyed. The rate of PDD was significantly higher at coastal hospitals than inland hospitals (17.3% versus 6.3%; Pdisaster deaths in non-DBHs were most numerous in facilities with few general beds, especially among patients hospitalized before the disaster in hospitals with fewer than 100 beds. Categorized by area, the most frequent causes of PDD were: insufficient medical resources, disrupted lifelines, delayed medical intervention, and deteriorated environmental conditions in homes and emergency shelters in coastal areas; and were delayed medical intervention and disrupted lifelines in inland areas. Categorized by hospital function, the most frequent causes were: delayed medical intervention, deteriorated environmental conditions in homes and emergency shelters, and insufficient medical resources at DBHs; while those at non-DBHs were disrupted lifelines, insufficient medical resources, delayed medical intervention, and lack of capacity for transport within the area. Preventable disaster death at medical institutions in areas

SOCIETAL IMPLICATIONS OF GREAT HANSHIN-AWAJI EARTHQUAKE DISASTER OF JANUARY 17,1995

OpenAIRE

Haruo, HAYASHI; Yoshiaki, KAWATA; Associate Professor, Research Center for Disaster Reduction Systems, Disaster Prevention Research Institute, Kyoto University; Professor, Research Center for Disaster Reduction Systems, Disaster Prevention Research Institute, Kyoto University

1995-01-01

A brief overview of what happened during the first month after the Hyogoken-nambu earthquake of January 17,1995 is given in terms both of the emergency responses initiated and the societal impact. For emergency responses, formal organization responses are discussed in reference to "Saigai taisaku kihon-ho (the Fundamental Disaster Management Law)" and "Saigai kyujyo-ho (the Disaster Relief Law)". Using the Kobe Fire Department as an example, search and rescue efforts as well as fire suppressi...

Societal implications of great Hanshin-awaji earthquake disaster of January 17, 1995

OpenAIRE

KAWATA, Yoshiaki; HAYASHI, Haruo

1995-01-01

A brief overview of what happened during the first month after the Hyogoken-nambu earthquake of January 17, 1995 is given in terms both of the emergency responses initiated and the societal impact. For emergency responses, formal organization responses are discussed in reference to "Saigai taisaku kihon-ho (the Fundamental Disaster Management Law)" and "Saigai kyujyo-ho (the Disaster Relief Law)". Using the Kobe Fire Department as an example, search and rescue efforts as well as fire suppress...

Monitoring Seismic Velocity Change to Explore the Earthquake Seismogenic Structures

Science.gov (United States)

Liao, C. F.; Wen, S.; Chen, C.

2017-12-01

Studying spatial-temporal variations of subsurface velocity structures is still a challenge work, but it can provide important information not only on geometry of a fault, but also the rheology change induced from the strong earthquake. In 1999, a disastrous Chi-Chi earthquake (Mw7.6; Chi-Chi EQ) occurred in central Taiwan and caused great impacts on Taiwan's society. Therefore, the major objective of this research is to investigate whether the rheology change of fault can be associated with seismogenic process before strong earthquake. In addition, after the strike of the Chi-Chi EQ, whether the subsurface velocity structure resumes to its steady state is another issue in this study. Therefore, for the above purpose, we have applied a 3D tomographic technique to obtain P- and S-wave velocity structures in central Taiwan using travel time data provided by the Central Weather Bureau (CWB). One major advantage of this method is that we can include out-of-network data to improve the resolution of velocity structures at deeper depths in our study area. The results show that the temporal variations of Vp are less significant than Vs (or Vp/Vs ratio), and Vp is not prominent perturbed before and after the occurrence of the Chi-Chi EQ. However, the Vs (or Vp/Vs ratio) structure in the source area demonstrates significant spatial-temporal difference before and after the mainshock. From the results, before the mainshock, Vs began to decrease (Vp/Vs ratio was increased as well) at the hanging wall of Chelungpu fault, which may be induced by the increasing density of microcracks and fluid. But in the vicinities of Chi-Chi Earthquake's source area, Vs was increasing (Vp/Vs ratio was also decreased). This phenomenon may be owing to the closing of cracks or migration of fluid. Due to the different physical characteristics around the source area, strong earthquake may be easily nucleated at the junctional zone. Our findings suggest that continuously monitoring the Vp and Vs (or

Paleoearthquake rupture behavior and recurrence of great earthquakes along the Haiyuan fault, northwestern China

Institute of Scientific and Technical Information of China (English)

ZHANG Peizhen; MIN Wei; DENG Qidong; MAO Fengying

2005-01-01

The Haiyuan fault is a major seismogenic fault in north-central China where the1920 Haiyuan earthquake of magnitude 8.5 occurred, resulting in more than 220000 deaths. The fault zone can be divided into three segments based on their geometric patterns and associated geomorphology. To study paleoseismology and recurrent history of devastating earthquakes along the fault, we dug 17 trenches along different segments of the fault zone. Although only 10of them allow the paleoearthquake event to be dated, together with the 8 trenches dug previously they still provide adequate information that enables us to capture major paleoearthquakes occurring along the fault during the past geological time. We discovered 3 events along the eastern segment during the past 14000 a, 7 events along the middle segment during the past 9000 a, and 6 events along the western segment during the past 10000 a. These events clearly depict two temporal clusters. The first cluster occurs from 4600 to 6400 a, and the second occurs from 1000to 2800 a, approximately. Each cluster lasts about 2000 a. Time period between these two clusters is also about 2000 a. Based on fault geometry, segmentation pattern, and paleoearthquake events along the Haiyuan fault we can identify three scales of earthquake rupture: rupture of one segment, cascade rupture of two segments, and cascade rupture of entire fault (three segments).Interactions of slip patches on the surface of the fault may cause rupture on one patch or ruptures of more than two to three patchs to form the complex patterns of cascade rupture events.

Paleoseismic Records of 1762 and Similar Prior Earthquakes Along the South-Eastern Coast of Bangladesh

Science.gov (United States)

Mondal, D. R.; McHugh, C. M.; Mortlock, R. A.; Gurung, D.; Bastas-Hernandez, A.; Steckler, M. S.; Seeber, L.; Mustaque, S.; Goodbred, S. L., Jr.; Akhter, S. H.; Saha, P.

2014-12-01

The great 1762 Arakan earthquake caused subsidence and uplift along 700km of the Arakan coast, and is thought to derive from a huge megathrust rupture reaching northward onto the southeastern coast of Bangladesh. Paleoseismic investigations were conducted in that area to document effects of that and prior earthquakes. U/Th ages obtained from isochron analysis of uplifted dead coral heads of the Poritesspecies, collected along a south to north transect from the islands east coast reveal at least three growth interruptions caused by abrupt relative sea-level changes within the past 1300 years that we interpret to be associated with megathrust ruptures. The ages show distinct events approximately 250, 900 and 1300 years ago. The youngest of these events corresponds to the 1762 Great Arakan earthquake. The two prior events at ~1100 and 700 AD, suggest an average recurrence interval of 400-600 years. Along the coast of Teknaf, we mapped a ~2m uplifted terrace. Marine shells on top of the terrace dated with C-14 at 1695-1791 AD link the uplift to the 1762 Great Arakan earthquake. Based on this evidence and previous work (Wang et al., 2013 and Aung et al., 2008), we estimated the 1762 rupture to be at least 700 km long, from Chebuda Island to the Sitakund anticline encompassing the Teknaf Peninsula. Considering 14 mm/yr convergence rate and 400-600 yrs recurrence interval, this rupture zone has now accumulated elastic deformation to generate a M~8.4 earthquake, close to the M8.8 estimated by Cummins (2007) for the 1762 earthquake. Published recurrence intervals based on C-14 ages along the Myanmar coast ~90 km south of Bangladesh reveal three ruptures within the last 3400 years with an average recurrence interval of 1000-2000 years (Aung et al., 2008). While the 1762 rupture reached across both areas, some of the prior ruptures may be confined to one or the other of these areas, with a smaller magnitude. Our precise U-Th ages provide evidence of recurrence intervals of

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

Long-term outcomes of patients evacuated from hospitals near the Fukushima Daiichi nuclear power plant after the Great East Japan Earthquake.

Science.gov (United States)

Igarashi, Yutaka; Tagami, Takashi; Hagiwara, Jun; Kanaya, Takahiro; Kido, Norihiro; Omura, Mariko; Tosa, Ryoichi; Yokota, Hiroyuki

2018-01-01

After the accident of the Fukushima Daiichi nuclear power plant due to the Great East Japan Earthquake in March 2011, the Japanese government issued a mandatory evacuation order for people living within a 20 km radius of the nuclear power plant. The aim of the current study was to investigate long-term outcomes of these patients and identify factors related to mortality. Patients who were evacuated from hospitals near the Fukushima Daiichi nuclear power plant to the Aizu Chuo Hospital from 15 to 26 March, 2011 were included in this study. The following data were collected from medical records: age, sex, activities of daily life, hospital they were admitted in at the time of earthquake, distance between the facility and the nuclear power plant, reasons of evacuation and number of transfers. The patient outcomes were collected from medical records and/or investigated on the telephone in January 2012. A total of 97 patients (28 men and 69 women) were transferred from 10 hospitals via ambulances or buses. No patients died or experienced exacerbation during transfer. Median age of the patients was 86 years. Of the total, 36 patients were not able to obey commands, 44 were bed-ridden and 61 were unable to sustain themselves via oral intake of food. Among 86 patients who were followed-up, 41 (48%) died at the end of 2011. Multiple-regression analysis showed that non-oral intake [Hazard Ratio (HR): 6.07, 95% Confidence interval (CI): 1.94-19.0] and male sex [HR: 8.35, 95% CI: 2.14-32.5] had significant impact on mortality. This study found that 48% of the evacuated patients died 9 months after the earthquake and they had significantly higher mortality rate than the nursing home residents. Non-oral intake and male sex had significant impact on mortality. These patients should be considered as especially vulnerable in case of hospital evacuation.

Incidence of Domestic Violence Against Pregnant Females After the Great East Japan Earthquake in Miyagi Prefecture: The Japan Environment and Children's Study.

Science.gov (United States)

Sakurai, Kasumi; Nishigori, Hidekazu; Nishigori, Toshie; Mizuno, Satoshi; Obara, Taku; Iwama, Noriyuki; Watanabe, Zen; Ishikuro, Mami; Tatsuta, Nozomi; Nishijima, Ichiko; Sugawara, Junichi; Fujiwara, Ikuma; Arima, Takahiro; Kuriyama, Shinichi; Metoki, Hirohito; Takahashi, Fumiaki; Nakai, Kunihiko; Yaegashi, Nobuo

2017-04-01

This study aimed to clarify the correlation between the 2011 Great East Japan Earthquake and domestic violence (DV) against pregnant females after the disaster in Miyagi Prefecture, an area damaged by the earthquake and tsunami. We analyzed 7600 pregnant females from June to December 2011. The incidence of physical and mental DV and the proportions in the inland, north coastal, and south coastal areas of Miyagi Prefecture and nationwide were calculated, and a chi-square test was conducted for comparison. The risk factors for DV were estimated with multivariate logistic regression analyses on a prefecture-wide basis. The incidence levels for physical DV were found to be 5.9% in the north coastal area, which was significantly higher than in the inland area (1.3%, P=0.0007) and nationwide (1.5%, P<0.0001). There were no significant differences in the incidence of mental DV between the 3 areas in Miyagi Prefecture (inland 15.2%, north coast 15.7%, and south coast 18.8%) or nationwide (13.8%). Experiencing disease or injury in someone close and changes in the family structure were significantly associated with mental DV in Miyagi Prefecture. Continuous monitoring and support for pregnant females may be necessary to address this issue in disaster-affected areas. (Disaster Med Public Health Preparedness. 2017;11:216-226).

Reliability of telecommunications systems following a major disaster: survey of secondary and tertiary emergency institutions in Miyagi Prefecture during the acute phase of the 2011 Great East Japan Earthquake.

Science.gov (United States)

Kudo, Daisuke; Furukawa, Hajime; Nakagawa, Atsuhiro; Abe, Yoshiko; Washio, Toshikatsu; Arafune, Tatsuhiko; Sato, Dai; Yamanouchi, Satoshi; Ochi, Sae; Tominaga, Teiji; Kushimoto, Shigeki

2014-04-01

Telecommunication systems are important for sharing information among health institutions to successfully provide medical response following disasters. The aim of this study was to clarify the problems associated with telecommunication systems in the acute phase of the Great East Japan Earthquake (March 11, 2011). All 72 of the secondary and tertiary emergency hospitals in Miyagi Prefecture were surveyed to evaluate the telecommunication systems in use during the 2011 Great Japan Earthquake, including satellite mobile phones, multi-channel access (MCA) wireless systems, mobile phones, Personal Handy-phone Systems (PHS), fixed-line phones, and the Internet. Hospitals were asked whether the telecommunication systems functioned correctly during the first four days after the earthquake, and, if not, to identify the cause of the malfunction. Each telecommunication system was considered to function correctly if the hospital staff could communicate at least once in every three calls. Valid responses were received from 53 hospitals (73.6%). Satellite mobile phones functioned correctly at the highest proportion of the equipped hospitals, 71.4%, even on Day 0. The MCA wireless system functioned correctly at the second highest proportion of the equipped hospitals. The systems functioned correctly at 72.0% on Day 0 and at 64.0% during Day 1 through Day 3. The main cause of malfunction of the MCA wireless systems was damage to the base station or communication lines (66.7%). Ordinary (personal or general communication systems) mobile phones did not function correctly at any hospital until Day 2, and PHS, fixed-line phones, and the Internet did not function correctly at any area hospitals that were severely damaged by the tsunami. Even in mildly damaged areas, these systems functioned correctly at telecommunications systems do not function.

A study of earthquake-induced building detection by object oriented classification approach

Science.gov (United States)

Sabuncu, Asli; Damla Uca Avci, Zehra; Sunar, Filiz

2017-04-01

Among the natural hazards, earthquakes are the most destructive disasters and cause huge loss of lives, heavily infrastructure damages and great financial losses every year all around the world. According to the statistics about the earthquakes, more than a million earthquakes occur which is equal to two earthquakes per minute in the world. Natural disasters have brought more than 780.000 deaths approximately % 60 of all mortality is due to the earthquakes after 2001. A great earthquake took place at 38.75 N 43.36 E in the eastern part of Turkey in Van Province on On October 23th, 2011. 604 people died and about 4000 buildings seriously damaged and collapsed after this earthquake. In recent years, the use of object oriented classification approach based on different object features, such as spectral, textural, shape and spatial information, has gained importance and became widespread for the classification of high-resolution satellite images and orthophotos. The motivation of this study is to detect the collapsed buildings and debris areas after the earthquake by using very high-resolution satellite images and orthophotos with the object oriented classification and also see how well remote sensing technology was carried out in determining the collapsed buildings. In this study, two different land surfaces were selected as homogenous and heterogeneous case study areas. In the first step of application, multi-resolution segmentation was applied and optimum parameters were selected to obtain the objects in each area after testing different color/shape and compactness/smoothness values. In the next step, two different classification approaches, namely "supervised" and "unsupervised" approaches were applied and their classification performances were compared. Object-based Image Analysis (OBIA) was performed using e-Cognition software.

Earthquake safety program at Lawrence Livermore National Laboratory

International Nuclear Information System (INIS)

Freeland, G.E.

1985-01-01

Within three minutes on the morning of January 24, 1980, an earthquake and three aftershocks, with Richter magnitudes of 5.8, 5.1, 4.0, and 4.2, respectively, struck the Livermore Valley. Two days later, a Richter magnitude 5.4 earthquake occurred, which had its epicenter about 4 miles northwest of the Lawrence Livermore National Laboratory (LLNL). Although no one at the Lab was seriously injured, these earthquakes caused considerable damage and disruption. Masonry and concrete structures cracked and broke, trailers shifted and fell off their pedestals, office ceilings and overhead lighting fell, and bookcases overturned. The Laboratory was suddenly immersed in a site-wide program of repairing earthquake-damaged facilities, and protecting our many employees and the surrounding community from future earthquakes. Over the past five years, LLNL has spent approximately $10 million on its earthquake restoration effort for repairs and upgrades. The discussion in this paper centers upon the earthquake damage that occurred, the clean-up and restoration efforts, the seismic review of LLNL facilities, our site-specific seismic design criteria, computer-floor upgrades, ceiling-system upgrades, unique building seismic upgrades, geologic and seismologic studies, and seismic instrumentation. 10 references

What was the role of nurses during the 2011 great East earthquake of Japan? An integrative review of the Japanese literature.

Science.gov (United States)

Kako, Mayumi; Ranse, Jamie; Yamamoto, Aiko; Arbon, Paul

2014-06-01

An earthquake and tsunami hit the east coast of Japan on March 11, 2011. Nurses were actively involved in the health response to this disaster and, subsequently, many authors have reported on the role nurses played in these efforts in Japanese nursing professional journals. Aim To describe the role of nurses who assisted in the 2011 Great East Earthquake of Japan by reviewing Japanese literature and reporting the findings in English. This research used an integrative literature review methodology. Manuscripts were obtained from the Japanese database Ichushi Ver. 5 (Japan Medical Abstracts Society, Tokyo, Japan). A total of 44 manuscripts were identified and included in a thematic analysis. Three main themes were identified: (1) nursing roles, (2) specialized nursing roles, and (3) preparedness education. Nurses fulfilled different roles in the period after the disaster (ie, as a clinician, a communicator, a leader, and a provider of psychosocial support). Additionally, the specialized nurse role was identified, along with the need for preparedness education to support the nurse's role in a disaster. The understanding of the role of nurses in disasters is expanding. There is a need to further explore the roles of specialized nurses in disasters. Further disaster education opportunities should be available as a part of continuing education for all nurses. Radiation aspects of disaster assistance should be included in disaster education programs where there are radio-nuclear hazards present in the environment.

IMMEDIATE MENTAL CONSEQUENCES OF THE GREAT EAST JAPAN EARTHQUAKE AND FUKUSHIMA NUCLEAR POWER PLANT ACCIDENT ON MOTHERS EXPERIENCING MISCARRIAGE, ABORTION, AND STILLBIRTH: THE FUKUSHIMA HEALTH MANAGEMENT SURVEY.

Science.gov (United States)

Yoshida-Komiya, Hiromi; Goto, Aya; Yasumura, Seiji; Fujimori, Keiya; Abe, Masafumi

2015-01-01

The Fukushima Pregnancy and Birth Survey was launched to monitor pregnant mothers' health after the Great East Japan Earthquake and Fukushima Daiichi Nuclear Power Plant (NPP) accident. Several lines of investigations have indicated that a disaster impacts maternal mental health with childbirth. However, there is no research regarding mental health of mothers with fetal loss after a disaster. In this report, we focus on those women immediately after the Great East Japan Earthquake and Fukushima NPP accident and discuss their support needs. Data regarding 61 miscarriages, 5 abortions, and 22 stillbirths were analyzed among the women who were pregnant at the time of the accident in the present study. We used a two-item case-finding instrument for depression screening, and compared the childbirth group with the fetal loss groups. We also analyzed mothers' opinions written as free-form text. Among the three fetal loss groups, the proportion of positive depression screens was significantly higher in the miscarriage and stillbirth group than in the childbirth group. Mothers' opinions were grouped into six categories, with pregnancy-related items being most common, especially in the miscarriage and stillbirth groups. A higher proportion of Fukushima mothers with fetal loss, especially those with miscarriage and stillbirth, had depressive symptoms compared to those who experienced childbirth. Health care providers need to pay close attention to this vulnerable group and respond to their concerns regarding the effects on their fertility.

Remarkable Changes in Behavior and Physiology of Laboratory Mice after the Massive 2011 Tohoku Earthquake in Japan

Science.gov (United States)

Yanai, Shuichi; Semba, Yuki; Endo, Shogo

2012-01-01

A devastating earthquake and tsunami hit Japan on March 11, 2011, followed by several long and intense aftershocks. Laboratory mice housed in the Tokyo, located approximately 330 km south of this earthquake’s epicenter, displayed remarkable changes in a variety of behaviors and physiological measures. Although unusual pre-earthquake behaviors have been previously reported in laboratory animals, little is known about behavioral and physiological changes that occur after a great earthquake. In the present study, the effects of Tohoku earthquake on mice behavior were investigated. “Earthquake-experienced” mice displayed a marked increase in food consumption without gaining body weight in response to the earthquake. They also displayed enhanced anxiety, and in a formal fear memory task, showed significantly greater tone- and context-dependent conditioned freezing. Water maze performance of earthquake-experienced mice showed the quicker acquisition of the task, faster swim speed and longer swim distance than the naive mice. Serum corticosterone levels were elevated compared to the naive mice, indicating that the earthquake and aftershocks were stressful for the mice. These results demonstrate that great earthquakes strongly affect mouse behaviors and physiology. Although the effects of a variety of experimental manipulations on mouse behaviors in disease models or in models of higher cognitive functions have been extensively examined, researchers need to be aware how natural phenomena, such as earthquakes and perhaps other natural environmental factors, influence laboratory animal behaviors and physiology. PMID:22957073

The HayWired earthquake scenario—We can outsmart disaster

Science.gov (United States)

Hudnut, Kenneth W.; Wein, Anne M.; Cox, Dale A.; Porter, Keith A.; Johnson, Laurie A.; Perry, Suzanne C.; Bruce, Jennifer L.; LaPointe, Drew

2018-04-18

The HayWired earthquake scenario, led by the U.S. Geological Survey (USGS), anticipates the impacts of a hypothetical magnitude-7.0 earthquake on the Hayward Fault. The fault is along the east side of California’s San Francisco Bay and is among the most active and dangerous in the United States, because it runs through a densely urbanized and interconnected region. One way to learn about a large earthquake without experiencing it is to conduct a scientifically realistic scenario. The USGS and its partners in the HayWired Coalition and the HayWired Campaign are working to energize residents and businesses to engage in ongoing and new efforts to prepare the region for such a future earthquake.

Empirical relations between instrumental and seismic parameters of some strong earthquakes of Colombia

International Nuclear Information System (INIS)

Marin Arias, Juan Pablo; Salcedo Hurtado, Elkin de Jesus; Castillo Gonzalez, Hardany

2008-01-01

In order to establish the relationships between macroseismic and instrumental parameters, macroseismic field of 28 historical earthquakes that produced great effects in the Colombian territory were studied. The integration of the parameters was made by using the methodology of Kaussel and Ramirez (1992), for great Chilean earthquakes; Kanamori and Anderson (1975) and Coppersmith and Well (1994) for world-wide earthquakes. Once determined the macroseismic and instrumental parameters it was come to establish the model of the source of each earthquake, with which the data base of these parameters was completed. For each earthquake parameters related to the local and normal macroseismic epicenter were complemented, depth of the local and normal center, horizontal extension of both centers, vertical extension of the normal center, model of the source, area of rupture. The obtained empirical relations from linear equations, even show behaviors very similar to the found ones by other authors for other regions of the world and to world-wide level. The results of this work allow establishing that certain mutual non compatibility exists between the area of rupture and the length of rupture determined by the macroseismic methods, with parameters found with instrumental data like seismic moment, Ms magnitude and Mw magnitude.

Evaluation of earthquake resistance design for underground structures of nuclear power plant, (1)

International Nuclear Information System (INIS)

Tohma, Junichi; Kokusho, Kenji; Iwatate, Takahiro; Ohtomo, Keizo

1986-01-01

As to earthquake resistant design of underground civil engineering structures related with emergency cooling water system of nuclear power plant, it is required these structures must maintain the function of great important their own facilities during earthquakes, especially for design earthquake motion. In this study, shaft pipline, pit and duct for cooling sea water facilities were chosen as typical underground structures, and the authors deal with the seismic design method for calculation of the principal sectional force in these structures generated by design earthquake motion. Especially, comparative investigations concerned with response displacement method versus dynamic analysis methods (lumped mass analysis and finite element analysis) are discussed. (author)

Short-term and long-term earthquake occurrence models for Italy: ETES, ERS and LTST

Directory of Open Access Journals (Sweden)

Maura Murru

2010-11-01

Full Text Available This study describes three earthquake occurrence models as applied to the whole Italian territory, to assess the occurrence probabilities of future (M ≥5.0 earthquakes: two as short-term (24 hour models, and one as long-term (5 and 10 years. The first model for short-term forecasts is a purely stochastic epidemic type earthquake sequence (ETES model. The second short-term model is an epidemic rate-state (ERS forecast based on a model that is physically constrained by the application to the earthquake clustering of the Dieterich rate-state constitutive law. The third forecast is based on a long-term stress transfer (LTST model that considers the perturbations of earthquake probability for interacting faults by static Coulomb stress changes. These models have been submitted to the Collaboratory for the Study of Earthquake Predictability (CSEP for forecast testing for Italy (ETH-Zurich, and they were locked down to test their validity on real data in a future setting starting from August 1, 2009.

Numerical Simulation of Stress evolution and earthquake sequence of the Tibetan Plateau

Science.gov (United States)

Dong, Peiyu; Hu, Caibo; Shi, Yaolin

2015-04-01

The India-Eurasia's collision produces N-S compression and results in large thrust fault in the southern edge of the Tibetan Plateau. Differential eastern flow of the lower crust of the plateau leads to large strike-slip faults and normal faults within the plateau. From 1904 to 2014, more than 30 earthquakes of Mw > 6.5 occurred sequentially in this distinctive tectonic environment. How did the stresses evolve during the last 110 years, how did the earthquakes interact with each other? Can this knowledge help us to forecast the future seismic hazards? In this essay, we tried to simulate the evolution of the stress field and the earthquake sequence in the Tibetan plateau within the last 110 years with a 2-D finite element model. Given an initial state of stress, the boundary condition was constrained by the present-day GPS observation, which was assumed as a constant rate during the 110 years. We calculated stress evolution year by year, and earthquake would occur if stress exceed the crustal strength. Stress changes due to each large earthquake in the sequence was calculated and contributed to the stress evolution. A key issue is the choice of initial stress state of the modeling, which is actually unknown. Usually, in the study of earthquake triggering, people assume the initial stress is zero, and only calculate the stress changes by large earthquakes - the Coulomb failure stress changes (Δ CFS). To some extent, this simplified method is a powerful tool because it can reveal which fault or which part of a fault becomes more risky or safer relatively. Nonetheless, it has not utilized all information available to us. The earthquake sequence reveals, though far from complete, some information about the stress state in the region. If the entire region is close to a self-organized critical or subcritical state, earthquake stress drop provides an estimate of lower limit of initial state. For locations no earthquakes occurred during the period, initial stress has to be

Regional Seismic Amplitude Modeling and Tomography for Earthquake-Explosion Discrimination

Science.gov (United States)

Walter, W. R.; Pasyanos, M. E.; Matzel, E.; Gok, R.; Sweeney, J.; Ford, S. R.; Rodgers, A. J.

2008-12-01

Empirically explosions have been discriminated from natural earthquakes using regional amplitude ratio techniques such as P/S in a variety of frequency bands. We demonstrate that such ratios discriminate nuclear tests from earthquakes using closely located pairs of earthquakes and explosions recorded on common, publicly available stations at test sites around the world (e.g. Nevada, Novaya Zemlya, Semipalatinsk, Lop Nor, India, Pakistan, and North Korea). We are examining if there is any relationship between the observed P/S and the point source variability revealed by longer period full waveform modeling. For example, regional waveform modeling shows strong tectonic release from the May 1998 India test, in contrast with very little tectonic release in the October 2006 North Korea test, but the P/S discrimination behavior appears similar in both events using the limited regional data available. While regional amplitude ratios such as P/S can separate events in close proximity, it is also empirically well known that path effects can greatly distort observed amplitudes and make earthquakes appear very explosion-like. Previously we have shown that the MDAC (Magnitude Distance Amplitude Correction, Walter and Taylor, 2001) technique can account for simple 1-D attenuation and geometrical spreading corrections, as well as magnitude and site effects. However in some regions 1-D path corrections are a poor approximation and we need to develop 2-D path corrections. Here we demonstrate a new 2-D attenuation tomography technique using the MDAC earthquake source model applied to a set of events and stations in both the Middle East and the Yellow Sea Korean Peninsula regions. We believe this new 2-D MDAC tomography has the potential to greatly improve earthquake-explosion discrimination, particularly in tectonically complex regions such as the Middle East.

Atmospheric Signals Associated with Major Earthquakes. A Multi-Sensor Approach. Chapter 9

Science.gov (United States)

Ouzounov, Dimitar; Pulinets, Sergey; Hattori, Katsumi; Kafatos, Menas; Taylor, Patrick

2011-01-01

We are studying the possibility of a connection between atmospheric observation recorded by several ground and satellites as earthquakes precursors. Our main goal is to search for the existence and cause of physical phenomenon related to prior earthquake activity and to gain a better understanding of the physics of earthquake and earthquake cycles. The recent catastrophic earthquake in Japan in March 2011 has provided a renewed interest in the important question of the existence of precursory signals preceding strong earthquakes. We will demonstrate our approach based on integration and analysis of several atmospheric and environmental parameters that were found associated with earthquakes. These observations include: thermal infrared radiation, radon! ion activities; air temperature and humidity and a concentration of electrons in the ionosphere. We describe a possible physical link between atmospheric observations with earthquake precursors using the latest Lithosphere-Atmosphere-Ionosphere Coupling model, one of several paradigms used to explain our observations. Initial results for the period of2003-2009 are presented from our systematic hind-cast validation studies. We present our findings of multi-sensor atmospheric precursory signals for two major earthquakes in Japan, M6.7 Niigata-ken Chuetsu-oki of July16, 2007 and the latest M9.0 great Tohoku earthquakes of March 11,2011

Update earthquake risk assessment in Cairo, Egypt

Science.gov (United States)

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

2017-07-01

and collapse prevention in future earthquakes, a five-step road map has been purposed.

The Mw=8.8 Maule earthquake aftershock sequence, event catalog and locations

Science.gov (United States)

Meltzer, A.; Benz, H.; Brown, L.; Russo, R. M.; Beck, S. L.; Roecker, S. W.

2011-12-01

The aftershock sequence of the Mw=8.8 Maule earthquake off the coast of Chile in February 2010 is one of the most well-recorded aftershock sequences from a great megathrust earthquake. Immediately following the Maule earthquake, teams of geophysicists from Chile, France, Germany, Great Britain and the United States coordinated resources to capture aftershocks and other seismic signals associated with this significant earthquake. In total, 91 broadband, 48 short period, and 25 accelerometers stations were deployed above the rupture zone of the main shock from 33-38.5°S and from the coast to the Andean range front. In order to integrate these data into a unified catalog, the USGS National Earthquake Information Center develop procedures to use their real-time seismic monitoring system (Bulletin Hydra) to detect, associate, location and compute earthquake source parameters from these stations. As a first step in the process, the USGS has built a seismic catalog of all M3.5 or larger earthquakes for the time period of the main aftershock deployment from March 2010-October 2010. The catalog includes earthquake locations, magnitudes (Ml, Mb, Mb_BB, Ms, Ms_BB, Ms_VX, Mc), associated phase readings and regional moment tensor solutions for most of the M4 or larger events. Also included in the catalog are teleseismic phases and amplitude measures and body-wave MT and CMT solutions for the larger events, typically M5.5 and larger. Tuning of automated detection and association parameters should allow a complete catalog of events to approximately M2.5 or larger for that dataset of more than 164 stations. We characterize the aftershock sequence in terms of magnitude, frequency, and location over time. Using the catalog locations and travel times as a starting point we use double difference techniques to investigate relative locations and earthquake clustering. In addition, phase data from candidate ground truth events and modeling of surface waves can be used to calibrate the

Water supply facility damage and water resource operation at disaster base hospitals in miyagi prefecture in the wake of the Great East Japan Earthquake.

Science.gov (United States)

Matsumura, Takashi; Osaki, Shizuka; Kudo, Daisuke; Furukawa, Hajime; Nakagawa, Atsuhiro; Abe, Yoshiko; Yamanouchi, Satoshi; Egawa, Shinichi; Tominaga, Teiji; Kushimoto, Shigeki

2015-04-01

The aim of this study was to shed light on damage to water supply facilities and the state of water resource operation at disaster base hospitals in Miyagi Prefecture (Japan) in the wake of the Great East Japan Earthquake (2011), in order to identify issues concerning the operational continuity of hospitals in the event of a disaster. In addition to interview and written questionnaire surveys to 14 disaster base hospitals in Miyagi Prefecture, a number of key elements relating to the damage done to water supply facilities and the operation of water resources were identified from the chronological record of events following the Great East Japan Earthquake. Nine of the 14 hospitals experienced cuts to their water supplies, with a median value of three days (range=one to 20 days) for service recovery time. The hospitals that could utilize well water during the time that water supply was interrupted were able to obtain water in quantities similar to their normal volumes. Hospitals that could not use well water during the period of interruption, and hospitals whose water supply facilities were damaged, experienced significant disruption to dialysis, sterilization equipment, meal services, sanitation, and outpatient care services, though the extent of disruption varied considerably among hospitals. None of the hospitals had determined the amount of water used for different purposes during normal service or formulated a plan for allocation of limited water in the event of a disaster. The present survey showed that it is possible to minimize the disruption and reduction of hospital functions in the event of a disaster by proper maintenance of water supply facilities and by ensuring alternative water resources, such as well water. It is also clear that it is desirable to conclude water supply agreements and formulate strategic water allocation plans in preparation for the eventuality of a long-term interruption to water services.

How did rehabilitation professionals act when faced with the Great East Japan earthquake and disaster? Descriptive epidemiology of disability and an interim report of the relief activities of the ten Rehabilitation-Related Organizations.

OpenAIRE

Liu, Meigen; Kohzuki, Masahiro; Hamamura, Akinori; Ishikawa, Makoto; Saitoh, Masami; Kurihara, Masaki; Handa, Kazuto; Nakamura, Haruki; Fukaura, Junichi; Kimura, Ryuji; Ito, Takao; Matsuzaka, Nobuou

2012-01-01

Objective: Inter-organizational coordination is important for rehabilitation disaster relief. The 2011 Great East Japan Earthquake and Disaster was unprecedented, being geographically widespread and multifaceted. Faced with the crisis, rehabilitation professionals established the 10 Rehabilitation- Related Organizations of Rehabilitation Support Service (10-RRO). The objectives of this paper are to provide descriptive epidemiology and assess the activities of 10- RRO. Design: Descriptive. Met...

Has El Salvador Fault Zone produced M ≥ 7.0 earthquakes? The 1719 El Salvador earthquake

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Canora, C.; Martínez-Díaz, J.; Álvarez-Gómez, J.; Villamor, P.; Ínsua-Arévalo, J.; Alonso-Henar, J.; Capote, R.

2013-05-01

Historically, large earthquakes, Mw ≥ 7.0, in the Εl Salvador area have been attributed to activity in the Cocos-Caribbean subduction zone. Τhis is correct for most of the earthquakes of magnitude greater than 6.5. However, recent paleoseismic evidence points to the existence of large earthquakes associated with rupture of the Εl Salvador Fault Ζone, an Ε-W oriented strike slip fault system that extends for 150 km through central Εl Salvador. Τo calibrate our results from paleoseismic studies, we have analyzed the historical seismicity of the area. In particular, we suggest that the 1719 earthquake can be associated with paleoseismic activity evidenced in the Εl Salvador Fault Ζone. Α reinterpreted isoseismal map for this event suggests that the damage reported could have been a consequence of the rupture of Εl Salvador Fault Ζone, rather than rupture of the subduction zone. Τhe isoseismal is not different to other upper crustal earthquakes in similar tectonovolcanic environments. We thus challenge the traditional assumption that only the subduction zone is capable of generating earthquakes of magnitude greater than 7.0 in this region. Τhis result has broad implications for future risk management in the region. Τhe potential occurrence of strong ground motion, significantly higher and closer to the Salvadorian populations that those assumed to date, must be considered in seismic hazard assessment studies in this area.

A Kinesthetic Demonstration for Locating Earthquake Epicenters

Science.gov (United States)

Keyantash, J.; Sperber, S.

2005-12-01

During Spring 2005, an inquiry-based curriculum for plate tectonics was developed for implementation in sixth-grade classrooms within the Los Angeles Unified School District (LAUSD). Two cohorts of LAUSD teachers received training and orientation to the plate tectonics unit during one week workshops in July 2005. However, during the training workshops, it was observed that there was considerable confusion among the teachers as to how the traditional "textbook" explanation of the time lag between P and S waves on a seismogram could possibly be used to determine the epicenter of an earthquake. One of the State of California science content standards for sixth grade students is that they understand how the epicenters of earthquakes are determined, so it was critical that the teachers themselves grasped the concept. In response to the adult learner difficulties, the classroom explanation of earthquake epicenter location was supplemented with an outdoor kinesthetic activity. Based upon the experience of the kinesthetic model, it was found that the hands-on model greatly cemented the teachers' understanding of the underlying theory. This paper details the steps of the kinesthetic demonstration for earthquake epicenter identification, as well as offering extended options for its classroom implementation.

Incorporating human-triggered earthquake risks into energy and water policies

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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.

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

Creating a Global Building Inventory for Earthquake Loss Assessment and Risk Management

Science.gov (United States)

Jaiswal, Kishor; Wald, David J.

2008-01-01

Earthquakes have claimed approximately 8 million lives over the last 2,000 years (Dunbar, Lockridge and others, 1992) and fatality rates are likely to continue to rise with increased population and urbanizations of global settlements especially in developing countries. More than 75% of earthquake-related human casualties are caused by the collapse of buildings or structures (Coburn and Spence, 2002). It is disheartening to note that large fractions of the world's population still reside in informal, poorly-constructed & non-engineered dwellings which have high susceptibility to collapse during earthquakes. Moreover, with increasing urbanization half of world's population now lives in urban areas (United Nations, 2001), and half of these urban centers are located in earthquake-prone regions (Bilham, 2004). The poor performance of most building stocks during earthquakes remains a primary societal concern. However, despite this dark history and bleaker future trends, there are no comprehensive global building inventories of sufficient quality and coverage to adequately address and characterize future earthquake losses. Such an inventory is vital both for earthquake loss mitigation and for earthquake disaster response purposes. While the latter purpose is the motivation of this work, we hope that the global building inventory database described herein will find widespread use for other mitigation efforts as well. For a real-time earthquake impact alert system, such as U.S. Geological Survey's (USGS) Prompt Assessment of Global Earthquakes for Response (PAGER), (Wald, Earle and others, 2006), we seek to rapidly evaluate potential casualties associated with earthquake ground shaking for any region of the world. The casualty estimation is based primarily on (1) rapid estimation of the ground shaking hazard, (2) aggregating the population exposure within different building types, and (3) estimating the casualties from the collapse of vulnerable buildings. Thus, the

A Sex Disparity Among Earthquake Victims.

Science.gov (United States)

Ardagh, Michael; Standring, Sarah; Deely, Joanne M; Johnston, David; Robinson, Viki; Gulliver, Pauline; Richardson, Sandra; Dierckx, Alieke; Than, Martin

2016-02-01

Understanding who is most vulnerable during an earthquake will help health care responders prepare for future disasters. We analyzed the demography of casualties from the Christchurch earthquake in New Zealand. The demography of the total deceased, injured, and hospitalized casualties of the Christchurch earthquake was compared with that of the greater Christchurch population, the Christchurch central business district working population, and patients who presented to the single acute emergency department on the same month and day over the prior 10 years. Sex data were compared to scene of injury, context of injury, clinical characteristics of injury, and injury severity scores. Significantly more females than males were injured or killed in the entire population of casualties (P20% were injured at commercial or service localities (444/2032 males [22%]; 1105/4627 females [24%]). Adults aged between 20 and 69 years (1639/2032 males [81%]; 3717/4627 females [80%]) were most frequently injured. Where people were and what they were doing at the time of the earthquake influenced their risk of injury.

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

Directory of Open Access Journals (Sweden)

A. Suppasri

2012-01-01

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

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

Directory of Open Access Journals (Sweden)

George Pararas-Carayannis

2006-01-01

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

The maximum earthquake in future T years: Checking by a real catalog

International Nuclear Information System (INIS)

Pisarenko, V.F.; Rodkin, M.V.

2015-01-01

The studies of disaster statistics are being largely carried out in recent decades. Some recent achievements in the field can be found in Pisarenko and Rodkin (2010). An important aspect in the seismic risk assessment is the using historical earthquake catalogs and the combining historical data with instrumental ones since historical catalogs cover very long time periods and can improve seismic statistics in the higher magnitude domain considerably. We suggest the new statistical technique for this purpose and apply it to two historical Japan catalogs and the instrumental JMA catalog. The main focus of these approaches is on the occurrence of disasters of extreme sizes as the most important ones from practical point of view. Our method of statistical analysis of the size distribution in the uppermost range of extremely rare events was suggested, based on maximum size M max (τ) (e.g. earthquake energy, ground acceleration caused by earthquake, victims and economic losses from natural catastrophes, etc.) that will occur in a prescribed time interval τ. A new approach to the problem discrete data that we called “the magnitude spreading” is suggested. This method reduces discrete random value to continuous ones by addition a small uniformly distributed random components. We analyze this method in details and apply it to verification of parameters derived from two historical catalogs: the Usami earthquake catalog (599–1884) and the Utsu catalog (1885–1925). We compare their parameters with ones derived from the instrumental JMA catalog (1926–2014). The results of this verification are following: The Usami catalog is incompatible with the instrumental one, whereas parameters estimated from the Utsu catalog are statistically compatible in the higher magnitude domain with sample of M max (τ) derived from the JMA catalog

Clustered and transient earthquake sequences in mid-continents

Science.gov (United States)

Liu, M.; Stein, S. A.; Wang, H.; Luo, G.

2012-12-01

Earthquakes result from sudden release of strain energy on faults. On plate boundary faults, strain energy is constantly accumulating from steady and relatively rapid relative plate motion, so large earthquakes continue to occur so long as motion continues on the boundary. In contrast, such steady accumulation of stain energy does not occur on faults in mid-continents, because the far-field tectonic loading is not steadily distributed between faults, and because stress perturbations from complex fault interactions and other stress triggers can be significant relative to the slow tectonic stressing. Consequently, mid-continental earthquakes are often temporally clustered and transient, and spatially migrating. This behavior is well illustrated by large earthquakes in North China in the past two millennia, during which no single large earthquakes repeated on the same fault segments, but moment release between large fault systems was complementary. Slow tectonic loading in mid-continents also causes long aftershock sequences. We show that the recent small earthquakes in the Tangshan region of North China are aftershocks of the 1976 Tangshan earthquake (M 7.5), rather than indicators of a new phase of seismic activity in North China, as many fear. Understanding the transient behavior of mid-continental earthquakes has important implications for assessing earthquake hazards. The sequence of large earthquakes in the New Madrid Seismic Zone (NMSZ) in central US, which includes a cluster of M~7 events in 1811-1812 and perhaps a few similar ones in the past millennium, is likely a transient process, releasing previously accumulated elastic strain on recently activated faults. If so, this earthquake sequence will eventually end. Using simple analysis and numerical modeling, we show that the large NMSZ earthquakes may be ending now or in the near future.

Post-Earthquake Reconstruction — in Context of Housing

Science.gov (United States)

Sarkar, Raju

Comprehensive rescue and relief operations are always launched with no loss of time with active participation of the Army, Governmental agencies, Donor agencies, NGOs, and other Voluntary organizations after each Natural Disaster. There are several natural disasters occurring throughout the world round the year and one of them is Earthquake. More than any other natural catastrophe, an earthquake represents the undoing of our most basic pre-conceptions of the earth as the source of stability or the first distressing factor due to earthquake is the collapse of our dwelling units. Earthquake has affected buildings since people began constructing them. So after each earthquake a reconstruction of housing program is very much essential since housing is referred to as shelter satisfying one of the so-called basic needs next to food and clothing. It is a well-known fact that resettlement (after an earthquake) is often accompanied by the creation of ghettos and ensuing problems in the provision of infrastructure and employment. In fact a housing project after Bhuj earthquake in Gujarat, India, illustrates all the negative aspects of resettlement in the context of reconstruction. The main theme of this paper is to consider few issues associated with post-earthquake reconstruction in context of housing, all of which are significant to communities that have had to rebuild after catastrophe or that will face such a need in the future. Few of them are as follows: (1) Why rebuilding opportunities are time consuming? (2) What are the causes of failure in post-earthquake resettlement? (3) How can holistic planning after an earthquake be planned? (4) What are the criteria to be checked for sustainable building materials? (5) What are the criteria for success in post-earthquake resettlement? (6) How mitigation in post-earthquake housing can be made using appropriate repair, restoration, and strengthening concepts?

Effects of Huge Earthquakes on Earth Rotation and the length of Day

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Changyi Xu

2013-01-01

Full Text Available We calculated the co-seismic Earth rotation changes for several typical great earthquakes since 1960 based on Dahlen¡¦s analytical expression of Earth inertia moment change, the excitation functions of polar motion and, variation in the length of a day (ΔLOD. Then, we derived a mathematical relation between polar motion and earthquake parameters, to prove that the amplitude of polar motion is independent of longitude. Because the analytical expression of Dahlen¡¦s theory is useful to theoretically estimate rotation changes by earthquakes having different seismic parameters, we show results for polar motion and ΔLOD for various types of earthquakes in a comprehensive manner. The modeled results show that the seismic effect on the Earth¡¦s rotation decreases gradually with increased latitude if other parameters are unchanged. The Earth¡¦s rotational change is symmetrical for a 45° dip angle and the maximum changes appear at the equator and poles. Earthquakes at a medium dip angle and low latitudes produce large rotation changes. As an example, we calculate the polar motion and ΔLOD caused by the 2011 Tohoku-Oki Earthquake using two different fault models. Results show that a fine slip fault model is useful to compute co-seismic Earth rotation change. The obtained results indicate Dahlen¡¦s method gives good approximations for computation of co-seismic rotation changes, but there are some differences if one considers detailed fault slip distributions. Finally we analyze and discuss the co-seismic Earth rotation change signal using GRACE data, showing that such a signal is hard to be detected at present, but it might be detected under some conditions. Numerical results of this study will serve as a good indicator to check if satellite observations such as GRACE can detect a seismic rotation change when a great earthquake occur.

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

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

2017-12-01

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

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

KAUST Repository

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

2017-01-01

In this study, earthquake rupture models for future mega-thrust earthquakes in the Nankai–Tonankai subduction zone are developed by incorporating the main characteristics of inverted source models of the 2011 Tohoku earthquake. These scenario

The Need for More Earthquake Science in Southeast Asia

Science.gov (United States)

Sieh, K.

2015-12-01

Many regions within SE Asia have as great a density of active seismic structures as does the western US - Sumatra, Myanmar, Bangladesh, New Guinea and the Philippines come first to mind. Much of Earth's release of seismic energy in the current millennium has, in fact, come from these regions, with great losses of life and livelihoods. Unfortunately, the scientific progress upon which seismic-risk reduction in SE Asia ultimately depends has been and continues to be slow. Last year at AGU, for example, I counted 57 talks about the M6 Napa earthquake. In contrast, I can't recall hearing any talk on a SE Asian M6 earthquake at any venue in the past many years. In fact, even M7+ earthquakes often go unstudied. Not uncommonly, the region's earthquake scientists face high financial and political impediments to conducting earthquake research. Their slow speed in the development of scientific knowledge doesn't bode well for speedy progress in the science of seismic hazards, the sine qua non for substantially reducing seismic risk. There are two basic necessities for the region to evolve significantly from the current state of affairs. Both involve the development of regional infrastructure: 1) Data: Robust and accessible geophysical monitoring systems would need to be installed, maintained and utilized by the region's earth scientists and their results shared internationally. Concomitantly, geological mapping (sensu lato) would need to be undertaken. 2) People: The training, employment, and enduring support of a new, young, international corps of earth scientists would need to accelerate markedly. The United States could play an important role in achieving the goal of significant seismic risk reduction in the most seismically active countries of SE Asia by taking the lead in establishing a coalition to robustly fund a multi-decadal program that supports scientists and their research institutions to work alongside local expertise.

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

level of shaking intensity with empirical models of fatality losses calibrated on past earthquakes in each country. Non-seismic detections and macroseismic questionnaires collected online are combined to identify as many as possible of the felt earthquakes regardless their magnitude. Non seismic detections include Twitter earthquake detections, developed by the US Geological Survey, where the number of tweets containing the keyword "earthquake" is monitored in real time and flashsourcing, developed by the EMSC, which detect traffic surges on its rapid earthquake information website caused by the natural convergence of eyewitnesses who rush to the Internet to investigate the cause of the shaking that they have just felt. All together, we estimate that the number of detected felt earthquakes is around 1 000 per year, compared with the 35 000 earthquakes annually reported by the EMSC! Felt events are already the subject of the web page "Latest significant earthquakes" on EMSC website (http://www.emsc-csem.org/Earthquake/significant_earthquakes.php) and of a dedicated Twitter service @LastQuake. We will present the identification process of the earthquakes that matter, the smartphone application itself (to be released in May) and its future evolutions.

Academia Sinica, TW E-science to Assistant Seismic Observations for Earthquake Research, Monitor and Hazard Reduction Surrounding the South China Sea

Science.gov (United States)

Huang, Bor-Shouh; Liu, Chun-Chi; Yen, Eric; Liang, Wen-Tzong; Lin, Simon C.; Huang, Win-Gee; Lee, Shiann-Jong; Chen, Hsin-Yen

Experience from the 1994 giant Sumatra earthquake, seismic and tsunami hazard have been considered as important issues in the South China Sea and its surrounding region, and attracted many seismologist's interesting. Currently, more than 25 broadband seismic instruments are currently operated by Institute of Earth Sciences, Academia Sinica in northern Vietnam to study the geodynamic evolution of the Red river fracture zone and rearranged to distribute to southern Vietnam recently to study the geodynamic evolution and its deep structures of the South China Sea. Similar stations are planned to deploy in Philippines in near future. In planning, some high quality stations may be as permanent stations and added continuous GPS observations, and instruments to be maintained and operated by several cooperation institutes, for instance, Institute of Geophysics, Vietnamese Acadamy of Sciences and Technology in Vietnam and Philippine Institute of Volcanology and Seismology in Philippines. Finally, those stations will be planed to upgrade as real time transmission stations for earthquake monitoring and tsunami warning. However, high speed data transfer within different agencies is always a critical issue for successful network operation. By taking advantage of both EGEE and EUAsiaGrid e-Infrastructure, Academia Sinica Grid Computing Centre coordinates researchers from various Asian countries to construct a platform to high performance data transfer for huge parallel computation. Efforts from this data service and a newly build earthquake data centre for data management may greatly improve seismic network performance. Implementation of Grid infrastructure and e-science issues in this region may assistant development of earthquake research, monitor and natural hazard reduction. In the near future, we will search for new cooperation continually from the surrounding countries of the South China Sea to install new seismic stations to construct a complete seismic network of the

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

International Nuclear Information System (INIS)

Yamazaki, Tatsuhiro

2012-01-01

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

Sensitivity of Earthquake Loss Estimates to Source Modeling Assumptions and Uncertainty

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Reasenberg, Paul A.; Shostak, Nan; Terwilliger, Sharon

2006-01-01

Introduction: This report explores how uncertainty in an earthquake source model may affect estimates of earthquake economic loss. Specifically, it focuses on the earthquake source model for the San Francisco Bay region (SFBR) created by the Working Group on California Earthquake Probabilities. The loss calculations are made using HAZUS-MH, a publicly available computer program developed by the Federal Emergency Management Agency (FEMA) for calculating future losses from earthquakes, floods and hurricanes within the United States. The database built into HAZUS-MH includes a detailed building inventory, population data, data on transportation corridors, bridges, utility lifelines, etc. Earthquake hazard in the loss calculations is based upon expected (median value) ground motion maps called ShakeMaps calculated for the scenario earthquake sources defined in WGCEP. The study considers the effect of relaxing certain assumptions in the WG02 model, and explores the effect of hypothetical reductions in epistemic uncertainty in parts of the model. For example, it addresses questions such as what would happen to the calculated loss distribution if the uncertainty in slip rate in the WG02 model were reduced (say, by obtaining additional geologic data)? What would happen if the geometry or amount of aseismic slip (creep) on the region's faults were better known? And what would be the effect on the calculated loss distribution if the time-dependent earthquake probability were better constrained, either by eliminating certain probability models or by better constraining the inherent randomness in earthquake recurrence? The study does not consider the effect of reducing uncertainty in the hazard introduced through models of attenuation and local site characteristics, although these may have a comparable or greater effect than does source-related uncertainty. Nor does it consider sources of uncertainty in the building inventory, building fragility curves, and other assumptions

Eight Personal Characteristics Associated with the Power to Live with Disasters as Indicated by Survivors of the 2011 Great East Japan Earthquake Disaster.

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Motoaki Sugiura

Full Text Available People perceive, judge, and behave differently in disasters and in a wide range of other difficult situations depending on their personal characteristics. The power to live, as captured by characteristics that are advantageous for survival in such situations, has thus far been modeled in arbitrary ways. Conceptualizing such characteristics in more objective ways may be helpful for systematic preparations for future disasters and life difficulties. Here, we attempted to identify the major factors of the power to live by summarizing the opinions of survivors of the 2011 Great East Japan Earthquake disaster. We conducted personal interviews with 78 survivors about their survival experiences and elicited their opinions about the power to live as relevant to those experiences. We then incorporated these opinions into a questionnaire that was completed by 1400 survivors. Factor analysis identified eight factors related to the power to live: leadership, problem solving, altruism, stubbornness, etiquette, emotional regulation, self-transcendence, and active well-being. All factors had sufficient internal construct validity, and six of them showed significant associations with one or more measures of survival success in the disaster, including immediate tsunami evacuation, problem solving in refugee situations, recovery during reconstruction, physical health, and mental health. Overall, the personal characteristics described by the eight factors largely overlap with those described in previous arbitrary models. Further research should investigate the domains, phases, and contexts in which each factor contributes to survival, address whether the factors are rooted in nature or in nurture, and explore their psychological or physiological bases.

Eight Personal Characteristics Associated with the Power to Live with Disasters as Indicated by Survivors of the 2011 Great East Japan Earthquake Disaster.

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Sugiura, Motoaki; Sato, Shosuke; Nouchi, Rui; Honda, Akio; Abe, Tsuneyuki; Muramoto, Toshiaki; Imamura, Fumihiko

2015-01-01

People perceive, judge, and behave differently in disasters and in a wide range of other difficult situations depending on their personal characteristics. The power to live, as captured by characteristics that are advantageous for survival in such situations, has thus far been modeled in arbitrary ways. Conceptualizing such characteristics in more objective ways may be helpful for systematic preparations for future disasters and life difficulties. Here, we attempted to identify the major factors of the power to live by summarizing the opinions of survivors of the 2011 Great East Japan Earthquake disaster. We conducted personal interviews with 78 survivors about their survival experiences and elicited their opinions about the power to live as relevant to those experiences. We then incorporated these opinions into a questionnaire that was completed by 1400 survivors. Factor analysis identified eight factors related to the power to live: leadership, problem solving, altruism, stubbornness, etiquette, emotional regulation, self-transcendence, and active well-being. All factors had sufficient internal construct validity, and six of them showed significant associations with one or more measures of survival success in the disaster, including immediate tsunami evacuation, problem solving in refugee situations, recovery during reconstruction, physical health, and mental health. Overall, the personal characteristics described by the eight factors largely overlap with those described in previous arbitrary models. Further research should investigate the domains, phases, and contexts in which each factor contributes to survival, address whether the factors are rooted in nature or in nurture, and explore their psychological or physiological bases.

Margin-Wide Earthquake Subspace Scanning Along the Cascadia Subduction Zone Using the Cascadia Initiative Amphibious Dataset

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Morton, E.; Bilek, S. L.; Rowe, C. A.

2017-12-01

Understanding the spatial extent and behavior of the interplate contact in the Cascadia Subduction Zone (CSZ) may prove pivotal to preparation for future great earthquakes, such as the M9 event of 1700. Current and historic seismic catalogs are limited in their integrity by their short duration, given the recurrence rate of great earthquakes, and by their rather high magnitude of completeness for the interplate seismic zone, due to its offshore distance from these land-based networks. This issue is addressed via the 2011-2015 Cascadia Initiative (CI) amphibious seismic array deployment, which combined coastal land seismometers with more than 60 ocean-bottom seismometers (OBS) situated directly above the presumed plate interface. We search the CI dataset for small, previously undetected interplate earthquakes to identify seismic patches on the megathrust. Using the automated subspace detection method, we search for previously undetected events. Our subspace comprises eigenvectors derived from CI OBS and on-land waveforms extracted for existing catalog events that appear to have occurred on the plate interface. Previous work focused on analysis of two repeating event clusters off the coast of Oregon spanning all 4 years of deployment. Here we expand earlier results to include detection and location analysis to the entire CSZ margin during the first year of CI deployment, with more than 200 new events detected for the central portion of the margin. Template events used for subspace scanning primarily occurred beneath the land surface along the coast, at the downdip edge of modeled high slip patches for the 1700 event, with most concentrated at the northwestern edge of the Olympic Peninsula.

The SCEC/USGS dynamic earthquake rupture code verification exercise

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Harris, R.A.; Barall, M.; Archuleta, R.; Dunham, E.; Aagaard, Brad T.; Ampuero, J.-P.; Bhat, H.; Cruz-Atienza, Victor M.; Dalguer, L.; Dawson, P.; Day, S.; Duan, B.; Ely, G.; Kaneko, Y.; Kase, Y.; Lapusta, N.; Liu, Yajing; Ma, S.; Oglesby, D.; Olsen, K.; Pitarka, A.; Song, S.; Templeton, E.

2009-01-01

Numerical simulations of earthquake rupture dynamics are now common, yet it has been difficult to test the validity of these simulations because there have been few field observations and no analytic solutions with which to compare the results. This paper describes the Southern California Earthquake Center/U.S. Geological Survey (SCEC/USGS) Dynamic Earthquake Rupture Code Verification Exercise, where codes that simulate spontaneous rupture dynamics in three dimensions are evaluated and the results produced by these codes are compared using Web-based tools. This is the first time that a broad and rigorous examination of numerous spontaneous rupture codes has been performed—a significant advance in this science. The automated process developed to attain this achievement provides for a future where testing of codes is easily accomplished.Scientists who use computer simulations to understand earthquakes utilize a range of techniques. Most of these assume that earthquakes are caused by slip at depth on faults in the Earth, but hereafter the strategies vary. Among the methods used in earthquake mechanics studies are kinematic approaches and dynamic approaches.The kinematic approach uses a computer code that prescribes the spatial and temporal evolution of slip on the causative fault (or faults). These types of simulations are very helpful, especially since they can be used in seismic data inversions to relate the ground motions recorded in the field to slip on the fault(s) at depth. However, these kinematic solutions generally provide no insight into the physics driving the fault slip or information about why the involved fault(s) slipped that much (or that little). In other words, these kinematic solutions may lack information about the physical dynamics of earthquake rupture that will be most helpful in forecasting future events.To help address this issue, some researchers use computer codes to numerically simulate earthquakes and construct dynamic, spontaneous

Earthquakes

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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 ...

Our response to the earthquake at Onagawa Nuclear Power Station

International Nuclear Information System (INIS)

Hirakawa, Tomoshi

2008-01-01

When the Miyagi Offshore earthquake occurred on August 16, 2005, all three units at the Onagawa NPS were shut down automatically according to the Strong Seismic Acceleration' signal. Our inspection after the earthquake confirmed there was no damage to the equipment of the nuclear power plants, but the analysis of the response spectrum observed at the bedrock showed the earthquake had exceeded the 'design-basis earthquake', at certain periods, so that we implemented a review of the seismic safety of plant facilities. In the review, the ground motion of Miyagi Offshore Earthquake which are predicted to occur in the near future were reexamined based on the observation data, and then 'The Ground Motion for Safety Check' surpassing the supposed ground motion of the largest earthquake was established. The seismic safety of plant facilities, important for safety, was assured. At present, No.1 to No.3 units at Onagawa NPS have returned to normal operation. (author)

Theatre as Therapy, Therapy as Theatre Transforming the Memories and Trauma of the 21 September 1999 Earthquake in Taiwan

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Chang, Ivy I-Chu

2005-01-01

On 21 September 1999, a 7.3 magnitude earthquake in Taiwan destroyed more than 100,000 houses, causing 2,294 deaths and 8,737 injuries. In the aftermath of the earthquake, a great number of social workers and cultural workers were thrust into Nantou County and Taichung County of central Taiwan, the epicentre of the earthquake, to assist the…

Mitigating the consequences of future earthquakes in historical centres: what perspectives from the joined use of past information and geological-geophysical surveys?

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Terenzio Gizzi, Fabrizio; Moscatelli, Massimiliano; Potenza, Maria Rosaria; Zotta, Cinzia; Simionato, Maurizio; Pileggi, Domenico; Castenetto, Sergio

2015-04-01

To mitigate the damage effects of earthquakes in urban areas and particularly in historical centres prone to high seismic hazard is an important task to be pursued. As a matter of fact, seismic history throughout the world informs us that earthquakes have caused deep changes in the ancient urban conglomerations due to their high building vulnerability. Furthermore, some quarters can be exposed to an increase of seismic actions if compared with adjacent areas due to the geological and/or topographical features of the site on which the historical centres lie. Usually, the strategies aimed to estimate the local seismic hazard make only use of the geological-geophysical surveys. Thorough this approach we do not draw any lesson from what happened as a consequences of past earthquakes. With this in mind, we present the results of a joined use of historical data and traditional geological-geophysical approach to analyse the effects of possible future earthquakes in historical centres. The research activity discussed here is arranged into a joint collaboration between the Department of Civil Protection of the Presidency of Council of Ministers, the Institute of Environmental Geology and Geoengineering and the Institute of Archaeological and Monumental Heritage of the National (Italian) Research Council. In order to show the results, we discuss the preliminary achievements of the integrated study carried out on two historical towns located in Southern Apennines, a portion of the Italian peninsula exposed to high seismic hazard. Taking advantage from these two test sites, we also discuss some methodological implications that could be taken as a reference in the seismic microzonation studies.

Assessment of precast beam-column using capacity demand response spectrum subject to design basis earthquake and maximum considered earthquake

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Ghani, Kay Dora Abd.; Tukiar, Mohd Azuan; Hamid, Nor Hayati Abdul

2017-08-01

Malaysia is surrounded by the tectonic feature of the Sumatera area which consists of two seismically active inter-plate boundaries, namely the Indo-Australian and the Eurasian Plates on the west and the Philippine Plates on the east. Hence, Malaysia experiences tremors from far distant earthquake occurring in Banda Aceh, Nias Island, Padang and other parts of Sumatera Indonesia. In order to predict the safety of precast buildings in Malaysia under near field ground motion the response spectrum analysis could be used for dealing with future earthquake whose specific nature is unknown. This paper aimed to develop of capacity demand response spectrum subject to Design Basis Earthquake (DBE) and Maximum Considered Earthquake (MCE) in order to assess the performance of precast beam column joint. From the capacity-demand response spectrum analysis, it can be concluded that the precast beam-column joints would not survive when subjected to earthquake excitation with surface-wave magnitude, Mw, of more than 5.5 Scale Richter (Type 1 spectra). This means that the beam-column joint which was designed using the current code of practice (BS8110) would be severely damaged when subjected to high earthquake excitation. The capacity-demand response spectrum analysis also shows that the precast beam-column joints in the prototype studied would be severely damaged when subjected to Maximum Considered Earthquake (MCE) with PGA=0.22g having a surface-wave magnitude of more than 5.5 Scale Richter, or Type 1 spectra.

Some rapid and long traveled landslides triggered by the May 12, 2008 Sichuan earthquake

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Wang, G.; Kamai, T.; Chigira, M.; Wu, X. Y.; Zhang, D. X.

2009-04-01

On May 12, 2008, a 7.9M earthquake struck Sichuan province of China, causing a huge number of death and injuries, and great loss of properties, becoming the most damaging earthquake since the 1976 Tangshan earthquake, in China. The collapse of buildings during the earthquake is the main reason for the casualties. There are a huge number of landslides that had been triggered by this earthquake. Almost all the roads to the mountainous areas had been blocked and many dams were formed by the displaced landslide materials, resulting in great difficulties for the aftershock rescue activities. Also a big portion of the casualties was directly caused by the landslides. The authors had reconnaissance field trips of the landslides, and performed preliminary investigation on some of the catastrophic ones. In this report, four landslides, i.e., Xiejiadian landslide in Pengzhou city, Donghekou landslide and Magongxiang landslide in Qingchuan County, and Niujuangou landslide on the epicenter area of Yingxiu Town, are introduced. The characteristics of deposited landslide masses in Donghekou landslide were investigated by means of a multichannel surface wave technique. Two earthquake recorders were installed at the upper part and deposit area of Donghekou landslide. The seismic responses of different parts of the landslides were monitored, and recorded successfully during the aftershocks that occurred in Qingchuan County on July 24, 2008. Also the drained and undrained dynamic shear behaviors of samples from the landslide areas were examined. Some preliminary analyzing results will be presented in this report.

Automatic Earthquake Shear Stress Measurement Method Developed for Accurate Time- Prediction Analysis of Forthcoming Major Earthquakes Along Shallow Active Faults

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Serata, S.

2006-12-01

basis to disclose an acting earthquake shear stress S at top of the tectonic plate is established at the depth of 600-800m (Window). This concept is supported by outcome of the Japanese government stress measurement made at the epicenter of the Kobe earthquake of 1995, where S is found to be less than 5 MPa. At the same time S at the earthquake active Ashio mining district was found to be 36 MPa (90 percent of maximum S) at Window. These findings led to formulation of a quantitative method proposed to monitor earthquake triggering potential in and around any growing earthquake stress nucleus along shallow active faults. For future earthquake time prediction, the Stressmeter can be applied first to survey general distribution of earthquake shear stress S along major active faults. A site with its shear stress greater than 30 MPa may be identified as a site of growing stress nucleus. A Stressmeter must be permanently buried at the site to monitor future stress growth toward a possible triggering by mathematical analysis of the stress excursion dynamics. This is made possible by the automatic stress measurement capability of the Stressmeter at a frequency up to 100 times per day. The significance of this approach is a possibility to save lives by time-prediction of a forthcoming major earthquake with accuracy in hours and minutes.

Mathematical models for estimating earthquake casualties and damage cost through regression analysis using matrices

International Nuclear Information System (INIS)

Urrutia, J D; Bautista, L A; Baccay, E B

2014-01-01

The aim of this study was to develop mathematical models for estimating earthquake casualties such as death, number of injured persons, affected families and total cost of damage. To quantify the direct damages from earthquakes to human beings and properties given the magnitude, intensity, depth of focus, location of epicentre and time duration, the regression models were made. The researchers formulated models through regression analysis using matrices and used α = 0.01. The study considered thirty destructive earthquakes that hit the Philippines from the inclusive years 1968 to 2012. Relevant data about these said earthquakes were obtained from Philippine Institute of Volcanology and Seismology. Data on damages and casualties were gathered from the records of National Disaster Risk Reduction and Management Council. This study will be of great value in emergency planning, initiating and updating programs for earthquake hazard reduction in the Philippines, which is an earthquake-prone country.

Earthquake clustering in modern seismicity and its relationship with strong historical earthquakes around Beijing, China

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Wang, Jian; Main, Ian G.; Musson, Roger M. W.

2017-11-01

Beijing, China's capital city, is located in a typical intraplate seismic belt, with relatively high-quality instrumental catalogue data available since 1970. The Chinese historical earthquake catalogue contains six strong historical earthquakes of Ms ≥ 6 around Beijing, the earliest in 294 AD. This poses a significant potential hazard to one of the most densely populated and economically active parts of China. In some intraplate areas, persistent clusters of events associated with historical events can occur over centuries, for example, the ongoing sequence in the New Madrid zone of the eastern US. Here we will examine the evidence for such persistent clusters around Beijing. We introduce a metric known as the `seismic density index' that quantifies the degree of clustering of seismic energy release. For a given map location, this multi-dimensional index depends on the number of events, their magnitudes, and the distances to the locations of the surrounding population of earthquakes. We apply the index to modern instrumental catalogue data between 1970 and 2014, and identify six clear candidate zones. We then compare these locations to earthquake epicentre and seismic intensity data for the six largest historical earthquakes. Each candidate zone contains one of the six historical events, and the location of peak intensity is within 5 km or so of the reported epicentre in five of these cases. In one case—the great Ms 8 earthquake of 1679—the peak is closer to the area of strongest shaking (Intensity XI or more) than the reported epicentre. The present-day event rates are similar to those predicted by the modified Omori law but there is no evidence of ongoing decay in event rates. Accordingly, the index is more likely to be picking out the location of persistent weaknesses in the lithosphere. Our results imply zones of high seismic density index could be used in principle to indicate the location of unrecorded historical of palaeoseismic events, in China and

Characteristics and Future Changes of Great Mississippi Flood Events in a Global Coupled Climate Model

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van der Wiel, K.; Kapnick, S. B.; Vecchi, G.; Smith, J. A.

2017-12-01

The Mississippi-Missouri river catchment houses millions of people and much of the U.S. national agricultural production. Severe flooding events can therefore have large negative societal, natural and economic impacts. GFDL FLOR, a global coupled climate model (atmosphere, ocean, land, sea ice with integrated river routing module) is used to investigate the characteristics of great Mississippi floods with an average return period of 100 years. Model experiments under pre-industrial greenhouse gas forcing were conducted for 3400 years, such that the most extreme flooding events were explicitly modeled and the land and/or atmospheric causes could be investigated. It is shown that melt of snow pack and frozen sub-surface water in the Missouri and Upper Mississippi basins prime the river system, subsequently sensitizing it to above average precipitation in the Ohio and Tennessee basins. The months preceding the greatest flooding events are above average wet, leading to moist sub-surface conditions. Anomalous melt depends on the availability of frozen water in the catchment, therefore anomalous amounts of sub-surface frozen water and anomalous large snow pack in winter (Nov-Feb) make the river system susceptible for these great flooding events in spring (Feb-Apr). An additional experiment of 1200 years under transient greenhouse gas forcing (RCP4.5, 5 members) was done to investigate potential future change in flood risk. Based on a peak-over-threshold method, it is found that the number of great flooding events decreases in a warmer future. This decrease coincides with decreasing occurrence of large melt events, but is despite increasing numbers of large precipitation events. Though the model results indicate a decreasing risk for the greatest flooding events, the predictability of events might decrease in a warmer future given the changing characters of melt and precipitation.

[Medium- and long-term health effects of the L'Aquila earthquake (Central Italy, 2009) and of other earthquakes in high-income Countries: a systematic review].

Science.gov (United States)

Ripoll Gallardo, Alba; Alesina, Marta; Pacelli, Barbara; Serrone, Dario; Iacutone, Giovanni; Faggiano, Fabrizio; Della Corte, Francesco; Allara, Elias

2016-01-01

to compare the methodological characteristics of the studies investigating the middle- and long-term health effects of the L'Aquila earthquake with the features of studies conducted after other earthquakes occurred in highincome Countries. a systematic comparison between the studies which evaluated the health effects of the L'Aquila earthquake (Central Italy, 6th April 2009) and those conducted after other earthquakes occurred in comparable settings. Medline, Scopus, and 6 sources of grey literature were systematically searched. Inclusion criteria comprised measurement of health outcomes at least one month after the earthquake, investigation of earthquakes occurred in high-income Countries, and presence of at least one temporal or geographical control group. out of 2,976 titles, 13 studies regarding the L'Aquila earthquake and 51 studies concerning other earthquakes were included. The L'Aquila and the Kobe/Hanshin- Awaji (Japan, 17th January 1995) earthquakes were the most investigated. Studies on the L'Aquila earthquake had a median sample size of 1,240 subjects, a median duration of 24 months, and used most frequently a cross sectional design (7/13). Studies on other earthquakes had a median sample size of 320 subjects, a median duration of 15 months, and used most frequently a time series design (19/51). the L'Aquila studies often focussed on mental health, while the earthquake effects on mortality, cardiovascular outcomes, and health systems were less frequently evaluated. A more intensive use of routine data could benefit future epidemiological surveillance in the aftermath of earthquakes.

Fukushima after the Great East Japan Earthquake: lessons for developing responsive and resilient health systems

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Fukuma, Shingo; Ahmed, Shahira; Goto, Rei; Inui, Thomas S; Atun, Rifat; Fukuhara, Shunichi

2017-01-01

Background On 11 March 2011, the Great East Japan Earthquake, followed by a tsunami and nuclear–reactor meltdowns, produced one of the most severe disasters in the history of Japan. The adverse impact of this ‘triple disaster’ on the health of local populations and the health system was substantial. In this study we examine population–level health indicator changes that accompanied the disaster, and discuss options for re–designing Fukushima’s health system, and by extension that of Japan, to enhance its responsiveness and resilience to current and future shocks. Methods We used country–level (Japan–average) or prefecture–level data (2005–2014) available from the portal site of Official Statistics of Japan for Fukushima, Miyagi, and Iwate, the prefectures that were most affected by the disaster, to compare trends before (2005–2010) and after (2011–2014) the ‘disaster’. We made time–trend line plots to describe changes over time in age–adjusted cause–specific mortality rates in each prefecture. Findings All three prefectures, and in particular Fukushima, had lower socio–economic indicators, an older population, lower productivity and gross domestic product per capita, and less higher–level industry than the Japan average. All three prefectures were ‘medically underserved’, with fewer physicians, nurses, ambulance calls and clinics per 100 000 residents than the Japan average. Even before the disaster, age–adjusted all–cause mortality in Fukushima was in general higher than the national rates. After the triple disaster we found that the mortality rate due to myocardial infarction increased substantially in Fukushima while it decreased nationwide. Compared to Japan average, spikes in mortality due to lung disease (all three prefectures), stroke (Iwate and Miyagi), and all–cause mortality (Miyagi and Fukushima) were also observed post–disaster. The cause–specific mortality rate from cancer followed similar trends in

Prediction of maximum earthquake intensities for the San Francisco Bay region

Science.gov (United States)

Borcherdt, Roger D.; Gibbs, James F.

1975-01-01

The intensity data for the California earthquake of April 18, 1906, are strongly dependent on distance from the zone of surface faulting and the geological character of the ground. Considering only those sites (approximately one square city block in size) for which there is good evidence for the degree of ascribed intensity, the empirical relation derived between 1906 intensities and distance perpendicular to the fault for 917 sites underlain by rocks of the Franciscan Formation is: Intensity = 2.69 - 1.90 log (Distance) (km). For sites on other geologic units intensity increments, derived with respect to this empirical relation, correlate strongly with the Average Horizontal Spectral Amplifications (AHSA) determined from 99 three-component recordings of ground motion generated by nuclear explosions in Nevada. The resulting empirical relation is: Intensity Increment = 0.27 +2.70 log (AHSA), and average intensity increments for the various geologic units are -0.29 for granite, 0.19 for Franciscan Formation, 0.64 for the Great Valley Sequence, 0.82 for Santa Clara Formation, 1.34 for alluvium, 2.43 for bay mud. The maximum intensity map predicted from these empirical relations delineates areas in the San Francisco Bay region of potentially high intensity from future earthquakes on either the San Andreas fault or the Hazard fault.

Prediction of maximum earthquake intensities for the San Francisco Bay region

Energy Technology Data Exchange (ETDEWEB)

Borcherdt, R.D.; Gibbs, J.F.

1975-01-01

The intensity data for the California earthquake of Apr 18, 1906, are strongly dependent on distance from the zone of surface faulting and the geological character of the ground. Considering only those sites (approximately one square city block in size) for which there is good evidence for the degree of ascribed intensity, the empirical relation derived between 1906 intensities and distance perpendicular to the fault for 917 sites underlain by rocks of the Franciscan formation is intensity = 2.69 - 1.90 log (distance) (km). For sites on other geologic units, intensity increments, derived with respect to this empirical relation, correlate strongly with the average horizontal spectral amplifications (AHSA) determined from 99 three-component recordings of ground motion generated by nuclear explosions in Nevada. The resulting empirical relation is intensity increment = 0.27 + 2.70 log (AHSA), and average intensity increments for the various geologic units are -0.29 for granite, 0.19 for Franciscan formation, 0.64 for the Great Valley sequence, 0.82 for Santa Clara formation, 1.34 for alluvium, and 2.43 for bay mud. The maximum intensity map predicted from these empirical relations delineates areas in the San Francisco Bay region of potentially high intensity from future earthquakes on either the San Andreas fault or the Hayward fault.

The support for a purification of water contaminated with radioactivity, and problems of the radioactivity standard in an emergency situation at the stricken area 2011 Great East Japan Earthquake

International Nuclear Information System (INIS)

Maeda, Yoshiaki

2011-01-01

The accident of the Fukushima Daiichi Nuclear Station of Tokyo Electric Power Company associated with the Great East Japan Earthquake incurred severe situation, where lifeline was cut off due to the discharge of a large amount of radioactive substances. In particular, the supply of safe foods and drinking water in radiation-polluted areas is urgently required. The authors have been developing up to now Crystal Valley water purifier and CV-Rescue water purifier that can purify well-water unsuitable for drinking due to contamination with toxic substances and produce drinkable water with safety without anxiety. This paper introduces the processes, in which verification test was performed to confirm that the above purifiers can be used for the removal of radioactivity discharged from the Great East Japan Earthquake this time, the validity of these purifiers was clarified, and these purifiers have actually been used for supporting water supply. This paper especially points out that a problem exists in the various standards on radioactivity that were temporarily determined in face of emergency of radiation pollution due to the nuclear power station accident this time. In these standards, the temporary standard on radioactive iodine 131 in drinking water is too high compared with the standards of WHO and those of advanced countries like U.S.A. It also points out the problem that radioactive substances in drinking water have not been removed yet. (O.A.)

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

Regional fault deformation characteristics before and after the Menyuan Ms6.4 earthquake

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Ning Li

2016-07-01

Full Text Available This study analyzes data regarding cross-fault deformations within the seismogenic zone of the 2016 Qinghai Menyuan Ms6.4 earthquake and its surrounding area. The results showed that the tendency anomaly sites near the epicenter had relatively long anomaly durations prior to the earthquake, while sudden-jumping anomaly sites started to increase in the middle eastern Qilian Mountains approximately a year before the earthquake and continued to increase and migrate towards the vicinity of the epicenter two to six months before the earthquake. Intensive observations a few days after the earthquake indicated that abnormal returns and turns before the earthquake were significant, but all had small amplitudes, and the coseismic effect was generally minor. In addition, the post-seismic tendency analysis of individual cross faults in the Qilian Mountain fault zone revealed an accelerating thrust tendency at all cross-fault sites in the middle Qilian Mountains after the 2008 Wenchuan Ms8.0 earthquake. This indicates that the Wenchuan mega-earthquake exerted a great impact on the dynamic environment of the northeastern margin of the Qinghai-Tibet plate and significantly enhanced the extrusion effect of the Indian plate on the middle Qilian Mountains, generating favorable conditions for the occurrence of Menyuan thrust earthquakes.