Scenario-based earthquake hazard and risk assessment for Baku (Azerbaijan

Directory of Open Access Journals (Sweden)

G. Babayev

2010-12-01

Full Text Available A rapid growth of population, intensive civil and industrial building, land and water instabilities (e.g. landslides, significant underground water level fluctuations, and the lack of public awareness regarding seismic hazard contribute to the increase of vulnerability of Baku (the capital city of the Republic of Azerbaijan to earthquakes. In this study, we assess an earthquake risk in the city determined as a convolution of seismic hazard (in terms of the surface peak ground acceleration, PGA, vulnerability (due to building construction fragility, population features, the gross domestic product per capita, and landslide's occurrence, and exposure of infrastructure and critical facilities. The earthquake risk assessment provides useful information to identify the factors influencing the risk. A deterministic seismic hazard for Baku is analysed for four earthquake scenarios: near, far, local, and extreme events. The seismic hazard models demonstrate the level of ground shaking in the city: PGA high values are predicted in the southern coastal and north-eastern parts of the city and in some parts of the downtown. The PGA attains its maximal values for the local and extreme earthquake scenarios. We show that the quality of buildings and the probability of their damage, the distribution of urban population, exposure, and the pattern of peak ground acceleration contribute to the seismic risk, meanwhile the vulnerability factors play a more prominent role for all earthquake scenarios. Our results can allow elaborating strategic countermeasure plans for the earthquake risk mitigation in the Baku city.

Probabilistic risk assessment of earthquakes at the Rocky Flats Plant and subsequent upgrade to reduce risk

International Nuclear Information System (INIS)

Day, S.A.

1989-01-01

An analysis to determine the risk associated with earthquakes at the Rocky Flats Plant was performed. Seismic analyses and structural evaluations were used to postulate building and equipment damage and radiological releases to the environment from various magnitudes of earthquakes. Dispersion modeling and dose assessment to the public were then calculated. The frequency of occurrence of various magnitudes of earthquakes were determined from the Department of Energy natural Phenomena Hazards Modeling Project. Risk to the public was probabilistically assessed for each magnitude of earthquake and for overall seismic risk. Based on the results of this Probabilistic Risk Assessment and a cost/benefit analysis, seismic upgrades are being implemented for several plutonium-handling facilities for the purpose of risk reduction

Bayesian probabilistic network approach for managing earthquake risks of cities

DEFF Research Database (Denmark)

Bayraktarli, Yahya; Faber, Michael

2011-01-01

This paper considers the application of Bayesian probabilistic networks (BPNs) to large-scale risk based decision making in regard to earthquake risks. A recently developed risk management framework is outlined which utilises Bayesian probabilistic modelling, generic indicator based risk models...... and a fourth module on the consequences of an earthquake. Each of these modules is integrated into a BPN. Special attention is given to aggregated risk, i.e. the risk contribution from assets at multiple locations in a city subjected to the same earthquake. The application of the methodology is illustrated...... on an example considering a portfolio of reinforced concrete structures in a city located close to the western part of the North Anatolian Fault in Turkey....

Geoethical suggestions for reducing risk of next (not only strong) earthquakes

Science.gov (United States)

Nemec, Vaclav

2013-04-01

Three relatively recent examples of earthquakes can be used as a background for suggesting geoethical views into any prediction accompanied by a risk analysis. ĹAquila earthquake (Italy - 2009): ĹAquila was largely destroyed by earthquakes in 1315, 1319, 1452, 1461, 1501, 1646, 1703 (until that time altogether about 3000 victims) and 1786 (about 6000 victims of this event only). The city was rebuilt and remained stable until October 2008, when tremors began again. From January 1 through April 5, 2009, additional 304 tremors were reported. When after measuring increased levels of radon emitted from the ground a local citizen (for many years working for the Italian National Institute of Astrophysics) predicted a major earthquake on Italian television, he was accused of being alarmist. Italy's National Commission for Prediction and Prevention of Major Risks met in L'Aquila for one hour on March 31, 2009, without really evaluating and characterising the risks that were present. On April 6 a 6.3 magnitude earthquake struck Aquila and nearby towns, killing 309 people and injuring more than 1,500. The quake also destroyed roughly 20,000 buildings, temporarily displacing another 65,000 people. In July 2010, prosecutor Fabio Picuti charged the Commission members with manslaughter and negligence for failing to warn the public of the impending risk. Many international organizations joined the chorus of criticism wrongly interpreting the accusation and sentence at the first stage as a problem of impossibility to predict earthquakes. - The Eyjafjallajokull volcano eruption (Iceland - 2010) is a reminder that in our globalized, interconnected world because of the increased sensibility of the new technology even a relatively small natural disaster may cause unexpected range of problems. - Earthquake and tsunami (Japan - 2011) - the most powerful known earthquake ever to have hit Japan on March 11. Whereas the proper earthquake with the magnitude of 9.0 has caused minimum of

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.

INTEGRATED FRAMEWORK FOR ENHANCING EARTHQUAKE RISK MITIGATION DECISIONS

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Temitope Egbelakin

2015-12-01

Full Text Available The increasing scale of losses from earthquake disasters has reinforced the need for property owners to become proactive in seismic risk reduction programs. However, despite advancement in seismic design methods and legislative frameworks, building owners are found unwilling or lack motivation to adopt adequate mitigation measures that will reduce their vulnerability to earthquake disasters. Various theories and empirical findings have been used to explain the adoption of protective behaviours including seismic mitigation decisions, but their application has been inadequate to enhance building owners’ protective decisions. A holistic framework that incorporates the motivational orientations of decision-making, coupled with the social, cultural, economic, regulatory, institutional and political realms of earthquake risk mitigation to enhance building owners’ decisions to voluntarily implement adequate mitigation measures, is proposed. This framework attempts to address any multi-disciplinary barriers that exist in earthquake disaster management, by ensuring that stakeholders involved in seismic mitigation decisions work together to foster seismic rehabilitation of EPBs, as well as illuminate strategies that will initiate, promote and sustain the adoption of long-term earthquake mitigation. .

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

Risk factors of suicidal ideation among adolescents after Wenchuan earthquake in China.

Science.gov (United States)

Ran, Mao-Sheng; Zhang, Zhen; Fan, Mei; Li, Rong-Hui; Li, Yuan-Hao; Ou, Guo Jing; Jiang, Zhe; Tong, Yu-Zhen; Fang, Ding-Zhi

2015-02-01

Suicidal ideation is a common phenomenon in survivors after disaster event. To identify the change of suicidal ideation, and to test hypotheses concerning the suicidal ideation, depression and PTSD symptoms among adolescent survivors after the 2008 Wenchuan earthquake in China. The suicidal ideation among high school students at 6, 12 and 18 months after the Wenchuan earthquake were investigated. Subjects included 737 student survivors in an affected high school. The PTSD Checklist-Civilian Version (PCL-C) and the Chinese Beck Depression Inventory (C-BDI) were used to measure the symptoms of PTSD and depression. The rates of suicidal ideation among the adolescent survivors at 6-, 12- and 18-month after the earthquake were 35.6%, 35.6% and 30.7% respectively. Depression symptoms in the 18-month follow-up, suicidal ideations at 6 and 12 months after the earthquake were the independent risk factors of suicidal ideation in the 18-month follow-up. Depression symptoms were the strongest predictor of suicidal ideation after earthquake. An increased rate of suicidal ideation after the earthquake may be mainly due to depression but not to PTSD symptoms. The disaster-related psychological sequelae and the risk factors of suicidal ideation, especially depression symptoms, should be considered in the mental health services and suicide prevention. Copyright © 2014 Elsevier B.V. All rights reserved.

Earthquake Hazard and Risk in Alaska

Science.gov (United States)

Black Porto, N.; Nyst, M.

2014-12-01

Alaska is one of the most seismically active and tectonically diverse regions in the United States. To examine risk, we have updated the seismic hazard model in Alaska. The current RMS Alaska hazard model is based on the 2007 probabilistic seismic hazard maps for Alaska (Wesson et al., 2007; Boyd et al., 2007). The 2015 RMS model will update several key source parameters, including: extending the earthquake catalog, implementing a new set of crustal faults, updating the subduction zone geometry and reoccurrence rate. First, we extend the earthquake catalog to 2013; decluster the catalog, and compute new background rates. We then create a crustal fault model, based on the Alaska 2012 fault and fold database. This new model increased the number of crustal faults from ten in 2007, to 91 faults in the 2015 model. This includes the addition of: the western Denali, Cook Inlet folds near Anchorage, and thrust faults near Fairbanks. Previously the subduction zone was modeled at a uniform depth. In this update, we model the intraslab as a series of deep stepping events. We also use the best available data, such as Slab 1.0, to update the geometry of the subduction zone. The city of Anchorage represents 80% of the risk exposure in Alaska. In the 2007 model, the hazard in Alaska was dominated by the frequent rate of magnitude 7 to 8 events (Gutenberg-Richter distribution), and large magnitude 8+ events had a low reoccurrence rate (Characteristic) and therefore didn't contribute as highly to the overall risk. We will review these reoccurrence rates, and will present the results and impact to Anchorage. We will compare our hazard update to the 2007 USGS hazard map, and discuss the changes and drivers for these changes. Finally, we will examine the impact model changes have on Alaska earthquake risk. Consider risk metrics include average annual loss, an annualized expected loss level used by insurers to determine the costs of earthquake insurance (and premium levels), and the

Probabilistic earthquake risk assessment as a tool to improve safety and explanatory adequacy

International Nuclear Information System (INIS)

Itoi, Tatsuya

2015-01-01

This paper explains the concept of probabilistic earthquake risk assessment, mainly from the viewpoint as a tool to improve safety and explanatory adequacy. The definition of risk is the expected value of undesirable effect in an engineering meaning that is likely to occur in the future, and it is defined in risk management as the triplet of scenario (what can happen), frequency, and impact. As for the earthquake risk assessment of a nuclear power plant, the fragility of structure / system / component (SSC) against earthquake (so-called earthquake fragility) is assessed, and by combining with the earthquake hazard that has been separately obtained, the occurrence frequency and impact of the accident are obtained. From the view of the authors, earthquake risk assessment is for the purpose of decision-making, and is not intended to calculate the probability in a scientifically rigorous manner. For ensuring the quality of risk assessment, the table of 'Expert utilization standards for the evaluation of epistemological uncertainty' is used. Sole quantitative risk assessment is not necessarily sufficient for risk management. It would be important to find how to build the 'framework for comprehensive decision-making.' (A.O.)

Insight into the Earthquake Risk Information Seeking Behavior of the Victims: Evidence from Songyuan, China

Directory of Open Access Journals (Sweden)

Shasha Li

2017-03-01

Full Text Available Efficient risk communication is a vital way to reduce the vulnerability of individuals when facing emergency risks, especially regarding earthquakes. Efficient risk communication aims at improving the supply of risk information and fulfilling the need for risk information by individuals. Therefore, an investigation into individual-level information seeking behavior within earthquake risk contexts is very important for improved earthquake risk communication. However, at present there are very few studies that have explored the behavior of individuals seeking earthquake risk information. Under the guidance of the Risk Information Seeking and Processing model as well as relevant practical findings using the structural equation model, this study attempts to explore the main determinants of an individual’s earthquake risk information seeking behavior, and to validate the mediator effect of information need during the seeking process. A questionnaire-based survey of 918 valid respondents in Songyuan, China, who had been hit by a small earthquake swarm, was used to provide practical evidence for this study. Results indicated that information need played a noteworthy role in the earthquake risk information seeking process, and was detected both as an immediate predictor and as a mediator. Informational subjective norms drive the seeking behavior on earthquake risk information through both direct and indirect approaches. Perceived information gathering capacity, negative affective responses and risk perception have an indirect effect on earthquake risk information seeking behavior via information need. The implications for theory and practice regarding risk communication are discussed and concluded.

Seismicity and earthquake risk in western Sicily

Directory of Open Access Journals (Sweden)

P. COSENTINO

1978-06-01

Full Text Available The seismicity and the earthquake risk in Western Sicily are here
evaluated on the basis of the experimental data referring to the historical
and instrumentally recorded earthquakes in this area (from 1248
up to 1968, which have been thoroughly collected, analyzed, tested and
normalized in order to assure the quasi-stationarity of the series of
events.
The approximated magnitude values — obtained by means of a compared
analysis of the magnitude and epicentral intensity values of the
latest events — have allowed to study the parameters of the frequency-
magnitude relation with both the classical exponential model and
the truncated exponential one previously proposed by the author.
So, the basic parameters, including the maximum possible regional
magnitude, have been estimated by means of different procedures, and
their behaviours have been studied as functions of the threshold magnitude.

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

OpenAIRE

Ibrion, Mihaela

2018-01-01

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

Initiatives to Reduce Earthquake Risk of Developing Countries

Science.gov (United States)

Tucker, B. E.

2008-12-01

The seventeen-year-and-counting history of the Palo Alto-based nonprofit organization GeoHazards International (GHI) is the story of many initiatives within a larger initiative to increase the societal impact of geophysics and civil engineering. GHI's mission is to reduce death and suffering due to earthquakes and other natural hazards in the world's most vulnerable communities through preparedness, mitigation and advocacy. GHI works by raising awareness in these communities about their risk and about affordable methods to manage it, identifying and strengthening institutions in these communities to manage their risk, and advocating improvement in natural disaster management. Some of GHI's successful initiatives include: (1) creating an earthquake scenario for Quito, Ecuador that describes in lay terms the consequences for that city of a probable earthquake; (2) improving the curricula of Pakistani university courses about seismic retrofitting; (3) training employees of the Public Works Department of Delhi, India on assessing the seismic vulnerability of critical facilities such as a school, a hospital, a police headquarters, and city hall; (4) assessing the vulnerability of the Library of Tibetan Works and Archives in Dharamsala, India; (5) developing a seismic hazard reduction plan for a nonprofit organization in Kathmandu, Nepal that works to manage Nepal's seismic risk; and (6) assisting in the formulation of a resolution by the Council of the Organization for Economic Cooperation and Development (OECD) to promote school earthquake safety among OECD member countries. GHI's most important resource, in addition to its staff and Board of Trustees, is its members and volunteer advisors, who include some of the world's leading earth scientists, earthquake engineers, urban planners and architects, from the academic, public, private and nonprofit sectors. GHI is planning several exciting initiatives in the near future. One would oversee the design and construction of

Building Inventory Database on the Urban Scale Using GIS for Earthquake Risk Assessment

Science.gov (United States)

Kaplan, O.; Avdan, U.; Guney, Y.; Helvaci, C.

2016-12-01

The majority of the existing buildings are not safe against earthquakes in most of the developing countries. Before a devastating earthquake, existing buildings need to be assessed and the vulnerable ones must be determined. Determining the seismic performance of existing buildings which is usually made with collecting the attributes of existing buildings, making the analysis and the necessary queries, and producing the result maps is very hard and complicated procedure that can be simplified with Geographic Information System (GIS). The aim of this study is to produce a building inventory database using GIS for assessing the earthquake risk of existing buildings. In this paper, a building inventory database for 310 buildings, located in Eskisehir, Turkey, was produced in order to assess the earthquake risk of the buildings. The results from this study show that 26% of the buildings have high earthquake risk, 33% of the buildings have medium earthquake risk and the 41% of the buildings have low earthquake risk. The produced building inventory database can be very useful especially for governments in dealing with the problem of determining seismically vulnerable buildings in the large existing building stocks. With the help of this kind of methods, determination of the buildings, which may collapse and cause life and property loss during a possible future earthquake, will be very quick, cheap and reliable.

The earthquake/seismic risk, vulnerability and capacity profile for ...

African Journals Online (AJOL)

The study was carried out to understand the risks posed by earthquakes in Karonga based on roles and perception of stakeholders. Information was collected from several stakeholders who were found responding to earthquakes impacts in Karonga Town. The study found that several stakeholders, governmental and ...

Risk assessment study of fire following earthquake: a case study of petrochemical enterprises in China

Science.gov (United States)

Li, J.; Wang, Y.; Chen, H.; Lin, L.

2013-04-01

After an earthquake, the fire risk of petrochemistry enterprises is higher than that of other enterprises as it involves production processes with inflammable and explosive characteristics. Using Chinese petrochemical enterprises as the research object, this paper uses a literature review and case summaries to study, amongst others, the classification of petrochemical enterprises, the proportion of daily fires, and fire loss ratio. This paper builds a fire following earthquake risk assessment model of petrochemical enterprises based on a previous earthquake fire hazard model, and the earthquake loss prediction assessment method, calculates the expected loss of the fire following earthquake in various counties and draws a risk map. Moreover, this research identifies high-risk areas, concentrating on the Beijing-Tianjin-Tangshan region, and Shandong, Jiangsu, and Zhejiang provinces. Differences in enterprise type produce different levels and distribution of petrochemical enterprises earthquake fire risk. Furthermore, areas at high risk of post-earthquake fires and with low levels of seismic fortification require extra attention to ensure appropriate mechanisms are in place.

Urban Policies and Earthquake Risk Mitigation

International Nuclear Information System (INIS)

Sarlo, Antonella

2008-01-01

The paper aims at proposing some considerations about some recent experiences of research carried out on the theme of earthquake risk mitigation and combining policies and actions of mitigation with urban development strategies. The objective was to go beyond the classical methodological approach aiming at defining a 'technical' evaluation of the earthquake risk through a procedure which can correlate the three 'components' of danger, exposure and vulnerability. These researches experiment, in terms of methodology and application, with a new category of interpretation and strategy: the so-called Struttura Urbana Minima (Minimum urban structure).Actually, the introduction of the Struttura Urbana Minima establishes a different approach towards the theme of safety in the field of earthquake risk, since it leads to a wider viewpoint, combining the building aspect of the issue with the purely urban one, involving not only town planning, but also social and managerial implications.In this sense the constituent logic of these researches is strengthened by two fundamental issues:- The social awareness of earthquake;- The inclusion of mitigation policies in the ordinary strategies for town and territory management. Three main aspects of the first point, that is of the 'social awareness of earthquake', characterize this issue and demand to be considered within a prevention policy:- The central role of the risk as a social production,- The central role of the local community consent,- The central role of the local community capability to planTherefore, consent, considered not only as acceptance, but above all as participation in the elaboration and implementation of choices, plays a crucial role in the wider issue of prevention policies.As far as the second point is concerned, the inclusion of preventive mitigation policies in ordinary strategies for the town and territory management demands the identification of criteria of choice and priorities of intervention and, as a

Surface Rupture Effects on Earthquake Moment-Area Scaling Relations

Science.gov (United States)

Luo, Yingdi; Ampuero, Jean-Paul; Miyakoshi, Ken; Irikura, Kojiro

2017-09-01

Empirical earthquake scaling relations play a central role in fundamental studies of earthquake physics and in current practice of earthquake hazard assessment, and are being refined by advances in earthquake source analysis. A scaling relation between seismic moment ( M 0) and rupture area ( A) currently in use for ground motion prediction in Japan features a transition regime of the form M 0- A 2, between the well-recognized small (self-similar) and very large (W-model) earthquake regimes, which has counter-intuitive attributes and uncertain theoretical underpinnings. Here, we investigate the mechanical origin of this transition regime via earthquake cycle simulations, analytical dislocation models and numerical crack models on strike-slip faults. We find that, even if stress drop is assumed constant, the properties of the transition regime are controlled by surface rupture effects, comprising an effective rupture elongation along-dip due to a mirror effect and systematic changes of the shape factor relating slip to stress drop. Based on this physical insight, we propose a simplified formula to account for these effects in M 0- A scaling relations for strike-slip earthquakes.

Vrancea earthquakes. Specific actions to mitigate seismic risk

International Nuclear Information System (INIS)

Marmureanu, Gheorghe; Marmureanu, Alexandru

2005-01-01

natural disasters given by earthquakes, there is a need to reverse trends in seismic risk mitigation to future events. Main courses of specific action to mitigate the seismic risks from strong deep Vrancea earthquakes should be considered as key to future development projects, including: - Early warning system for industrial facilities; - Short and long term prediction program of strong Vrancea earthquakes; - Seismic hazard map of Romania; - Seismic microzonation of large populated cities; - Shake map; - Seismic tomography of dams for avoiding disasters. The quality of life and the security of infrastructure (including human services, civil and industrial structures, financial infrastructure, information transmission and processing systems) in every nation are increasingly vulnerable to disasters caused by events that have geological, atmospheric, hydrologic, and technological origins. As UN Secretary General Kofi Annan pointed out, 'Building a culture of prevention is not easy. While the costs of prevention have to be paid in the present, its benefits lie in a distant future'. In other words: Prevention pays off. This may not always become apparent immediately, but, in the long run, the benefits from prevention measures will always outweigh their costs by far. Romania is an earthquake prone area and these main specific actions are really contributing to seismic risk mitigation. These specific actions are provided for in Law nr. 372/March 18,2004 -'The National Program of Seismic Risk Management'. (authors)

Change of Japanese risk perception after Tohoku earthquake March 11, 2011

International Nuclear Information System (INIS)

Nakajima, Reiko

2011-01-01

The present study reports change of Japanese risk perception based on the results of national surveys carried out in 2010 and 2011. Major earthquake and nuclear power plant risk items were perceived much more serious, while other risks such as global warming, illicit drugs, terrorism were perceiver less serious, after Tohoku earthquake. Anxiety about radiological material was differently according to the distance from the Fukushima No. 1 nuclear power plant. (author)

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)

Communicating Earthquake Preparedness: The Influence of Induced Mood, Perceived Risk, and Gain or Loss Frames on Homeowners' Attitudes Toward General Precautionary Measures for Earthquakes.

Science.gov (United States)

Marti, Michèle; Stauffacher, Michael; Matthes, Jörg; Wiemer, Stefan

2018-04-01

Despite global efforts to reduce seismic risk, actual preparedness levels remain universally low. Although earthquake-resistant building design is the most efficient way to decrease potential losses, its application is not a legal requirement across all earthquake-prone countries and even if, often not strictly enforced. Risk communication encouraging homeowners to take precautionary measures is therefore an important means to enhance a country's earthquake resilience. Our study illustrates that specific interactions of mood, perceived risk, and frame type significantly affect homeowners' attitudes toward general precautionary measures for earthquakes. The interdependencies of the variables mood, risk information, and frame type were tested in an experimental 2 × 2 × 2 design (N = 156). Only in combination and not on their own, these variables effectively influence attitudes toward general precautionary measures for earthquakes. The control variables gender, "trait anxiety" index, and alteration of perceived risk adjust the effect. Overall, the group with the strongest attitudes toward general precautionary actions for earthquakes are homeowners with induced negative mood who process high-risk information and gain-framed messages. However, the conditions comprising induced negative mood, low-risk information and loss-frame and induced positive mood, low-risk information and gain-framed messages both also significantly influence homeowners' attitudes toward general precautionary measures for earthquakes. These results mostly confirm previous findings in the field of health communication. For practitioners, our study emphasizes that carefully compiled communication measures are a powerful means to encourage precautionary attitudes among homeowners, especially for those with an elevated perceived risk. © 2017 Society for Risk Analysis.

Web-Based Real Time Earthquake Forecasting and Personal Risk Management

Science.gov (United States)

Rundle, J. B.; Holliday, J. R.; Graves, W. R.; Turcotte, D. L.; Donnellan, A.

2012-12-01

Earthquake forecasts have been computed by a variety of countries and economies world-wide for over two decades. For the most part, forecasts have been computed for insurance, reinsurance and underwriters of catastrophe bonds. One example is the Working Group on California Earthquake Probabilities that has been responsible for the official California earthquake forecast since 1988. However, in a time of increasingly severe global financial constraints, we are now moving inexorably towards personal risk management, wherein mitigating risk is becoming the responsibility of individual members of the public. Under these circumstances, open access to a variety of web-based tools, utilities and information is a necessity. Here we describe a web-based system that has been operational since 2009 at www.openhazards.com and www.quakesim.org. Models for earthquake physics and forecasting require input data, along with model parameters. The models we consider are the Natural Time Weibull (NTW) model for regional earthquake forecasting, together with models for activation and quiescence. These models use small earthquakes ('seismicity-based models") to forecast the occurrence of large earthquakes, either through varying rates of small earthquake activity, or via an accumulation of this activity over time. These approaches use data-mining algorithms combined with the ANSS earthquake catalog. The basic idea is to compute large earthquake probabilities using the number of small earthquakes that have occurred in a region since the last large earthquake. Each of these approaches has computational challenges associated with computing forecast information in real time. Using 25 years of data from the ANSS California-Nevada catalog of earthquakes, we show that real-time forecasting is possible at a grid scale of 0.1o. We have analyzed the performance of these models using Reliability/Attributes and standard Receiver Operating Characteristic (ROC) tests. We show how the Reliability and

Earthquake and volcanic risks: issues for the Bataan Nuclear Power Plant

International Nuclear Information System (INIS)

Solidum, Dr. Renato U.

2009-01-01

The proposed re-commissioning of the mothballed Bataan Nuclear Power Plant (BNPP) has raised objections that include the perceived unsafe siting of the BNPP on Mt. Natib, a potentially active volcano, in an earthquake-prone region. This concern must be evaluated through thorough seismological, paleo-seismic, volcanological and engineering studies. The BNPP sits on Napot Point on the southwest foot slope of Mt. Natib, an andesitic to dacitic stratovolcano just 30 kms south of Mt. Pinatubo. Natib's evolution is poorly known, but involved at least 3 explosive summit eruptions that formed a 6 km-diameter coalescent caldera and a younger 2-km diameter caldera. Pyroclastic flows define the cone surface, and available age dating includes a ±27 ka 14C age for a deposit on the eastern flanks and an 11-18 ka relative dating for suspected pyroclastic deposits in Subic Bay (1). Whether these represent the most recent eruptions is uncertain. A detailed magmatic/eruptive history defining magmatic recharge and eruption recurrence rates, from which probabilities for future eruptive activity can be analyzed, will be necessary for quantifying volcanic risk. Furthermore, Natib,Pinatubo and adjacent Mariveles are part of the Luzon Arc and associated with ongoing subduction along the Manila Trench. Subduction earthquakes are common, but apart from these, seismic risk is also being attributted to tectonic structures inland that include reported on site faults inferred from drilling, basin faults seen in reflection profiles (1), the Subic Bay Fault Zone delineated by magmatic studies (2) and various lineaments inferred from satellite imageries. These, plus seismicity in the region are being argued as indicators of earthquake threat. However, much emphasis is given maximum seismic magnitudes rather than peak ground accelerations (PGAs), epicentral rather than focal sources,and the inference of faults/lineaments rather than paleoseismic evidence of recent faulting. Paleoseismic studies of

The Global Earthquake Model and Disaster Risk Reduction

Science.gov (United States)

Smolka, A. J.

2015-12-01

Advanced, reliable and transparent tools and data to assess earthquake risk are inaccessible to most, especially in less developed regions of the world while few, if any, globally accepted standards currently allow a meaningful comparison of risk between places. The Global Earthquake Model (GEM) is a collaborative effort that aims to provide models, datasets and state-of-the-art tools for transparent assessment of earthquake hazard and risk. As part of this goal, GEM and its global network of collaborators have developed the OpenQuake engine (an open-source software for hazard and risk calculations), the OpenQuake platform (a web-based portal making GEM's resources and datasets freely available to all potential users), and a suite of tools to support modelers and other experts in the development of hazard, exposure and vulnerability models. These resources are being used extensively across the world in hazard and risk assessment, from individual practitioners to local and national institutions, and in regional projects to inform disaster risk reduction. Practical examples for how GEM is bridging the gap between science and disaster risk reduction are: - Several countries including Switzerland, Turkey, Italy, Ecuador, Papua-New Guinea and Taiwan (with more to follow) are computing national seismic hazard using the OpenQuake-engine. In some cases these results are used for the definition of actions in building codes. - Technical support, tools and data for the development of hazard, exposure, vulnerability and risk models for regional projects in South America and Sub-Saharan Africa. - Going beyond physical risk, GEM's scorecard approach evaluates local resilience by bringing together neighborhood/community leaders and the risk reduction community as a basis for designing risk reduction programs at various levels of geography. Actual case studies are Lalitpur in the Kathmandu Valley in Nepal and Quito/Ecuador. In agreement with GEM's collaborative approach, all

Earthquake prediction the ory and its relation to precursors

International Nuclear Information System (INIS)

Negarestani, A.; Setayeshi, S.; Ghannadi-Maragheh, M.; Akasheh, B.

2001-01-01

Since we don't have enough knowledge about the Physics of earthquakes. therefore. the study of seismic precursors plays an important role in earthquake prediction. Earthquake prediction is a science which discusses about precursory phenomena during seismogenic process, and then investigates the correlation and association among them and the intrinsic relation between precursors and the seismogenic process. ar the end judges comprehensively the seismic status and finally makes earthquake prediction. There are two ways for predicting earthquake prediction. The first is to study the physics of seismogenic process and to determine the parameters in the process based on the source theories and the second way is to use seismic precursors. In this paper the theory of earthquake is reviewed. We also study theory of earthquake using models of earthquake origin, the relation between seismogenic process and various accompanying precursory phenomena. The earthquake prediction is divided into three categories: long-term, medium-term and short-term. We study seismic anomalous behavior. electric field, crustal deformation, gravity. magnetism of earth. change of groundwater variation. groundwater geochemistry and change of Radon gas emission. Finally, it is concluded the there is a correlation between Radon gas emission and earthquake phenomena. Meanwhile, there are some samples from actual processing in this area

Evaluation of earthquake vibration on aseismic design of nuclear power plant judging from recent earthquakes

International Nuclear Information System (INIS)

Dan, Kazuo

2006-01-01

The Regulatory Guide for Aseismic Design of Nuclear Reactor Facilities was revised on 19 th September, 2006. Six factors for evaluation of earthquake vibration are considered on the basis of the recent earthquakes. They are 1) evaluation of earthquake vibration by method using fault model, 2) investigation and approval of active fault, 3) direct hit earthquake, 4) assumption of the short active fault as the hypocentral fault, 5) locality of the earthquake and the earthquake vibration and 6) remaining risk. A guiding principle of revision required new evaluation method of earthquake vibration using fault model, and evaluation of probability of earthquake vibration. The remaining risk means the facilities and people get into danger when stronger earthquake than the design occurred, accordingly, the scattering has to be considered at evaluation of earthquake vibration. The earthquake belt of Hyogo-Nanbu earthquake and strong vibration pulse in 1995, relation between length of surface earthquake fault and hypocentral fault, and distribution of seismic intensity of off Kushiro in 1993 are shown. (S.Y.)

Risk assessment study of fire following an earthquake: a case study of petrochemical enterprises in China

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Li, J.; Wang, Y.; Chen, H.; Lin, L.

2014-04-01

After an earthquake, the fire risk of petrochemical enterprises is higher than that of other enterprises as it involves production processes with inflammable and explosive characteristics. Using Chinese petrochemical enterprises as the research object, this paper uses a literature review and case summaries to study, amongst others, the classification of petrochemical enterprises, the proportion of daily fires, and fire loss ratio. This paper builds a fire following an earthquake risk assessment model of petrochemical enterprises based on a previous earthquake fire hazard model, and the earthquake loss prediction assessment method, calculates the expected loss of the fire following an earthquake in various counties and draws a risk map. Moreover, this research identifies high-risk areas, concentrating on the Beijing-Tianjin-Tangshan region, and Shandong, Jiangsu, and Zhejiang provinces. Differences in enterprise type produce different levels and distribution of petrochemical enterprise earthquake fire risk. Furthermore, areas at high risk of post-earthquake fires and with low levels of seismic fortification require extra attention to ensure appropriate mechanisms are in place.

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.

Intermediate-depth earthquakes facilitated by eclogitization-related stresses

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Nakajima, Junichi; Uchida, Naoki; Shiina, Takahiro; Hasegawa, Akira; Hacker, Bradley R.; Kirby, Stephen H.

2013-01-01

Eclogitization of the basaltic and gabbroic layer in the oceanic crust involves a volume reduction of 10%–15%. One consequence of the negative volume change is the formation of a paired stress field as a result of strain compatibility across the reaction front. Here we use waveform analysis of a tiny seismic cluster in the lower crust of the downgoing Pacific plate and reveal new evidence in favor of this mechanism: tensional earthquakes lying 1 km above compressional earthquakes, and earthquakes with highly similar waveforms lying on well-defined planes with complementary rupture areas. The tensional stress is interpreted to be caused by the dimensional mismatch between crust transformed to eclogite and underlying untransformed crust, and the earthquakes are probably facilitated by reactivation of fossil faults extant in the subducting plate. These observations provide seismic evidence for the role of volume change–related stresses and, possibly, fluid-related embrittlement as viable processes for nucleating earthquakes in downgoing oceanic lithosphere.

Earthquake Hazard and Risk in New Zealand

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Apel, E. V.; Nyst, M.; Fitzenz, D. D.; Molas, G.

2014-12-01

To quantify risk in New Zealand we examine the impact of updating the seismic hazard model. The previous RMS New Zealand hazard model is based on the 2002 probabilistic seismic hazard maps for New Zealand (Stirling et al., 2002). The 2015 RMS model, based on Stirling et al., (2012) will update several key source parameters. These updates include: implementation a new set of crustal faults including multi-segment ruptures, updating the subduction zone geometry and reccurrence rate and implementing new background rates and a robust methodology for modeling background earthquake sources. The number of crustal faults has increased by over 200 from the 2002 model, to the 2012 model which now includes over 500 individual fault sources. This includes the additions of many offshore faults in northern, east-central, and southwest regions. We also use the recent data to update the source geometry of the Hikurangi subduction zone (Wallace, 2009; Williams et al., 2013). We compare hazard changes in our updated model with those from the previous version. Changes between the two maps are discussed as well as the drivers for these changes. We examine the impact the hazard model changes have on New Zealand earthquake risk. Considered risk metrics include average annual loss, an annualized expected loss level used by insurers to determine the costs of earthquake insurance (and premium levels), and the loss exceedance probability curve used by insurers to address their solvency and manage their portfolio risk. We analyze risk profile changes in areas with large population density and for structures of economic and financial importance. New Zealand is interesting in that the city with the majority of the risk exposure in the country (Auckland) lies in the region of lowest hazard, where we don't have a lot of information about the location of faults and distributed seismicity is modeled by averaged Mw-frequency relationships on area sources. Thus small changes to the background rates

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

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Nyst, M.

2012-12-01

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

Vrancea earthquakes. Courses for specific actions to mitigate seismic risk

International Nuclear Information System (INIS)

Marmureanu, Gheorghe; Marmureanu, Alexandru

2005-01-01

Earthquakes in the Carpathian-Pannonian region are confined to the crust, except the Vrancea zone, where earthquakes with focal depth down to 200 Km occur. For example, the ruptured area migrated from 150 km to 180 km (November 10,1940, M w = 7.7) from 90 km to 110 km (March 4, 1977, M w 7.4), from 130 km to 150 km (August 30, 1986, M w = 7.1) and from 70 km to 90 km (May 30, 1990, M w = 6.9) depth. The depth interval between 110 km and 130 km remains not ruptured since 1802, October 26, when it was the strongest earthquake occurred in this part of Central Europe. The magnitude is assumed to be M w = 7.9 - 8.0 and this depth interval is a natural candidate for the next strong Vrancea event. While no country in the world is entirely safe, the lack of capacity to limit the impact of seismic hazards remains a major burden for all countries and while the world has witnessed an exponential increase in human and material losses due to natural disasters given by earthquakes, there is a need to reverse trends in seismic risk mitigation to future events. Main courses for specific actions to mitigate the seismic risk given by strong deep Vrancea earthquakes should be considered as key for development actions: - Early warning system for industrial facilities. Early warning is more than a technological instrument to detect, monitor and submit warnings. It should become part of a management information system for decision-making in the context of national institutional frameworks for disaster management and part of national and local strategies and programmers for risk mitigation; - Prediction program of Vrancea strong earthquakes of short and long term; - Hazard seismic map of Romania. The wrong assessment of the seismic hazard can lead to dramatic situations as those from Bucharest or Kobe. Before the 1977 Vrancea earthquake, the city of Bucharest was designed to intensity I = VII (MMI) and the real intensity was I = IX1/2-X (MMI); - Seismic microzonation of large populated

Relations between source parameters for large Persian earthquakes

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Majid Nemati

2015-11-01

Full Text Available Empirical relationships for magnitude scales and fault parameters were produced using 436 Iranian intraplate earthquakes of recently regional databases since the continental events represent a large portion of total seismicity of Iran. The relations between different source parameters of the earthquakes were derived using input information which has usefully been provided from the databases after 1900. Suggested equations for magnitude scales relate the body-wave, surface-wave as well as local magnitude scales to scalar moment of the earthquakes. Also, dependence of source parameters as surface and subsurface rupture length and maximum surface displacement on the moment magnitude for some well documented earthquakes was investigated. For meeting this aim, ordinary linear regression procedures were employed for all relations. Our evaluations reveal a fair agreement between obtained relations and equations described in other worldwide and regional works in literature. The M0-mb and M0-MS equations are correlated well to the worldwide relations. Also, both M0-MS and M0-ML relations have a good agreement with regional studies in Taiwan. The equations derived from this study mainly confirm the results of the global investigations about rupture length of historical and instrumental events. However, some relations like MW-MN and MN-ML which are remarkably unlike to available regional works (e.g., American and Canadian were also found.

Long-term effects of earthquake experience of young persons on cardiovascular disease risk factors

Science.gov (United States)

Li, Na; Wang, Yumei; Yu, Lulu; Song, Mei; Wang, Lan; Ji, Chunpeng

2016-01-01

Introduction The aim of the study was to study the long-term effect on cardiovascular disease risk factors of stress from direct experience of an earthquake as a young person. Material and methods We selected workers born between July 1, 1958 and July 1, 1976 who were examined at Kailuan General Hospital between May and October of 2013. Data on cardiovascular events were taken during the workers’ annual health examination conducted between 2006 and 2007. All subjects were divided into three groups according to their experience of the Tangshan earthquake of July 28, 1976, as follows: control group; exposed group 1 and exposed group 2. We compared cardiovascular disease risk factors between the three groups as well as by gender and age. Results One thousand one hundred and ninety-six workers were included in the final statistical analysis. Among all subjects, resting heart rate (p = 0.003), total cholesterol (p earthquake compared with unexposed controls, but were unrelated to loss of relatives. No significant difference in triglyceride levels was observed between the three groups (p = 0.900). Further refinement showed that the effects were restricted to males 40 years of age or older at the time of analysis, but were due primarily to age at the time of earthquake exposure (p = 0.002, p Earthquake experience in the early years of life has long-term effects on adult resting heart rate, total cholesterol, and fasting plasma glucose, especially among men. PMID:28144258

Engineering aspects of earthquake risk mitigation: Lessons from management of recent earthquakes, and consequential mudflows and landslides

International Nuclear Information System (INIS)

1992-01-01

The Proceedings contain 30 selected presentations given at the Second and Third UNDRO/USSR Training Seminars: Engineering Aspects of Earthquake Risk Assessment and Mitigation of Losses, held in Dushanbe, October 1988; and Lessons from Management of Recent Earthquakes, and Consequential Mudflows and Landslides, held in Moscow, October 1989. The annexes to the document provide information on the participants, the work programme and the resolution adopted at each of the seminars. Refs, figs and tabs

The association between exposure and psychological health in earthquake survivors from the Longmen Shan Fault area: the mediating effect of risk perception

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Jiuping Xu

2016-05-01

Full Text Available Abstract Background In this study, exposure refers to survivors who suffered from life-changing situations, such as personal injuries, the deaths or injury of family members, relatives or friends or the loss of or damage to personal or family property, as a result of the earthquake. The mediating effect of risk perception on the exposure and psychological health in survivors from the Longmen Shan Fault area and the moderating effect of social support on the relationship between risk perception and psychological health were both examined. Method A cross-sectional survey was conducted in a local Longmen Shan Fault area near the epicenter of the 2008 Wenchuan earthquake. The Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition (DSM-IV, the standard Chinese 12-item Short Form (SF-12v2, and the Social Support Rating Scale (SSRS were used to interview 2,080 earthquake survivors in the period one-year after the earthquake. Based on the environment and the characteristics of the Longmen Shan Fault area, a risk perception questionnaire was developed to evaluate survivor risk perception. Factor and regression analyses were conducted to determine the hypothetical relations. Results The analyses provided effective support for the hypothesized model. Survivor risk perception was classified into direct risk perception and indirect risk perception. Survivor direct risk perception was found to play a partial mediating role in the relationship between exposure and the two domains (Physical component summary (PCS and the Mental component summary (MCS of psychological health. Survivor indirect risk perception was found to have a only partial mediating effect on the association between exposure and MCS. Social support was found to moderate the influence of risk perception on psychological health. Conclusion Risk communication should be considered in future post-earthquake psychological assistance programs and social support strategies could also be

Statistical validation of earthquake related observations

Science.gov (United States)

Kossobokov, V. G.

2011-12-01

The confirmed fractal nature of earthquakes and their distribution in space and time implies that many traditional estimations of seismic hazard (from term-less to short-term ones) are usually based on erroneous assumptions of easy tractable or, conversely, delicately-designed models. The widespread practice of deceptive modeling considered as a "reasonable proxy" of the natural seismic process leads to seismic hazard assessment of unknown quality, which errors propagate non-linearly into inflicted estimates of risk and, eventually, into unexpected societal losses of unacceptable level. The studies aimed at forecast/prediction of earthquakes must include validation in the retro- (at least) and, eventually, in prospective tests. In the absence of such control a suggested "precursor/signal" remains a "candidate", which link to target seismic event is a model assumption. Predicting in advance is the only decisive test of forecast/predictions and, therefore, the score-card of any "established precursor/signal" represented by the empirical probabilities of alarms and failures-to-predict achieved in prospective testing must prove statistical significance rejecting the null-hypothesis of random coincidental occurrence in advance target earthquakes. We reiterate suggesting so-called "Seismic Roulette" null-hypothesis as the most adequate undisturbed random alternative accounting for the empirical spatial distribution of earthquakes: (i) Consider a roulette wheel with as many sectors as the number of earthquake locations from a sample catalog representing seismic locus, a sector per each location and (ii) make your bet according to prediction (i.e., determine, which locations are inside area of alarm, and put one chip in each of the corresponding sectors); (iii) Nature turns the wheel; (iv) accumulate statistics of wins and losses along with the number of chips spent. If a precursor in charge of prediction exposes an imperfection of Seismic Roulette then, having in mind

EARTHQUAKE-INDUCED DEFORMATION STRUCTURES AND RELATED TO EARTHQUAKE MAGNITUDES

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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.

Rethinking earthquake-related DC-ULF electromagnetic phenomena: towards a physics-based approach

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Q. Huang

2011-11-01

Full Text Available Numerous electromagnetic changes possibly related with earthquakes have been independently reported and have even been attempted to apply to short-term prediction of earthquakes. However, there are active debates on the above issue because the seismogenic process is rather complicated and the studies have been mainly empirical (i.e. a kind of experience-based approach. Thus, a physics-based study would be helpful for understanding earthquake-related electromagnetic phenomena and strengthening their applications. As a potential physics-based approach, I present an integrated research scheme, taking into account the interaction among observation, methodology, and physical model. For simplicity, this work focuses only on the earthquake-related DC-ULF electromagnetic phenomena. The main approach includes the following key problems: (1 how to perform a reliable and appropriate observation with some clear physical quantities; (2 how to develop a robust methodology to reveal weak earthquake-related electromagnetic signals from noisy background; and (3 how to develop plausible physical models based on theoretical analyses and/or laboratory experiments for the explanation of the earthquake-related electromagnetic signals observed in the field conditions.

A global building inventory for earthquake loss estimation and risk management

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Jaiswal, K.; Wald, D.; Porter, K.

2010-01-01

We develop a global database of building inventories using taxonomy of global building types for use in near-real-time post-earthquake loss estimation and pre-earthquake risk analysis, for the U.S. Geological Survey's Prompt Assessment of Global Earthquakes for Response (PAGER) program. The database is available for public use, subject to peer review, scrutiny, and open enhancement. On a country-by-country level, it contains estimates of the distribution of building types categorized by material, lateral force resisting system, and occupancy type (residential or nonresidential, urban or rural). The database draws on and harmonizes numerous sources: (1) UN statistics, (2) UN Habitat's demographic and health survey (DHS) database, (3) national housing censuses, (4) the World Housing Encyclopedia and (5) other literature. ?? 2010, Earthquake Engineering Research Institute.

Rural Households’ Livelihood Capital, Risk Perception, and Willingness to Purchase Earthquake Disaster Insurance: Evidence from Southwestern China

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Dingde Xu

2018-06-01

Full Text Available Earthquake disaster insurance can effectively reduce the impact of earthquake disasters on rural households. Exploring rural households’ willingness to purchase earthquake disaster insurance in earthquake disaster areas provides an understanding of the motivations underlying the implementation of an insurance policy. However, few studies have examined the perspectives of rural households, in order to explore the correlations between the rural households’ livelihood capital, their disaster risk perception, and their willingness to purchase earthquake disaster insurance. A cross-sectional survey data including 241 rural households from the most severe disaster counties (cities during the 5 • 12 Wenchuan earthquake was examined with regard to rural households’ livelihood and disaster risk perception, and ordinal logistic regression models were constructed to explore rural households’ willingness to purchase earthquake disaster insurance, as well as the driving mechanism behind this willingness. The results showed that 34.44% of rural households were very willing to purchase earthquake disaster insurance, and 7.05% of rural households were very reluctant to purchase earthquake insurance. Rural households’ livelihood capital and risk perceptions were the most important factors affecting their willingness to purchase earthquake disaster insurance. Rural households with higher scores on natural capital, physical capital, possibility, and worry were more likely to purchase earthquake disaster insurance. Specifically, keeping all other variables constant, every one unit increase in nature capital and physical capital corresponded to an increase in the odds of willingness to purchase earthquake disaster insurance by a factor of 0.14 and 0.06, respectively; every one unit increase in possibility and worry corresponded to an increase in the odds of willingness to purchase earthquake disaster insurance by a factor of 0.03 and 0.04, respectively

Gravity Variations Related to Earthquakes in the BTTZ Region in China

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Zheng, J.; Liu, K.; Lu, H.; Liu, D.; Chen, Y.; Kuo, J. T.

2006-05-01

Temporal variations of gravity before and after earthquakes have been observed since 1960s, but a definitive conclusion has not been reached concerning the relationship between the gravity variation and earthquake occurrence. Since 1980, the first US/China joint scientific research project has been monitoring micro-gravity variations related to earthquakes in the Beijing-Tianjin-Tangshan-Zhangjiekou (BTTZ) region in China through the establishment of a network of spatially and temporally continuous and discrete gravity stations. With the data of both temporally continuous and discrete data of gravity variations accumulated and analyzed, a general picture of gravity variation associated with the seismogenesis and occurrence of earthquakes in the BTTZ region has been emerged clearly. Some of the major findings are 1. Gravity variations before and after earthquakes exist spatially and temporally; 2. Gravity variation data of temporally continuous measurements are essential to monitor the variations of gravity related to earthquakes unless temporally discrete gravity data are made in very close time intervals. 3. Concept of epicentroid and hypocentroid with respect to the maximum values of gravity variation is valid and has been experimentally verified; 4. The gravity variations related to the occurrence of earthquakes in the BTTZ region for the magnitudes of 4-5 earthquakes support the proposed "combined dilatation model", i.e., a dual-dilatancy of diffusion dilatancy (D/D) and the fault zone dilatancy (FZD) models; 5. Although the temporally discrete gravity variation data were collected in a larger time interval of about six months in the BTTZ region, these gravity variation data, in some cases, indicate that these variations are related to the occurrence of earthquakes; 7. Subsurface fluids do play a very important role in the gravity variations that have not been recognized and emphasized previously; 7. With the temporally continuous gravity variation data, the

Global building inventory for earthquake loss estimation and risk management

Science.gov (United States)

Jaiswal, Kishor; Wald, David; Porter, Keith

2010-01-01

We develop a global database of building inventories using taxonomy of global building types for use in near-real-time post-earthquake loss estimation and pre-earthquake risk analysis, for the U.S. Geological Survey’s Prompt Assessment of Global Earthquakes for Response (PAGER) program. The database is available for public use, subject to peer review, scrutiny, and open enhancement. On a country-by-country level, it contains estimates of the distribution of building types categorized by material, lateral force resisting system, and occupancy type (residential or nonresidential, urban or rural). The database draws on and harmonizes numerous sources: (1) UN statistics, (2) UN Habitat’s demographic and health survey (DHS) database, (3) national housing censuses, (4) the World Housing Encyclopedia and (5) other literature.

Risk Management in Earthquakes, Financial Markets, and the Game of 21: The role of Forecasting, Nowcasting, and Timecasting

Science.gov (United States)

Rundle, J. B.

2017-12-01

Earthquakes and financial markets share surprising similarities [1]. For example, the well-known VIX index, which by definition is the implied volatility of the Standard and Poors 500 index, behaves in very similar quantitative fashion to time series for earthquake rates. Both display sudden increases at the time of an earthquake or an announcement of the US Federal Reserve Open Market Committee [2], and both decay as an inverse power of time. Both can be regarded as examples of first order phase transitions [1], and display fractal and scaling behavior associated with critical transitions, such as power-law magnitude-frequency relations in the tails of the distributions. Early quantitative investors such as Edward Thorpe and John Kelly invented novel methods to mitigate or manage risk in games of chance such as blackjack, and in markets using hedging techniques that are still in widespread use today. The basic idea is the concept of proportional betting, where the gambler/investor bets a fraction of the bankroll whose size is determined by the "edge" or inside knowledge of the real (and changing) odds. For earthquake systems, the "edge" over nature can only exist in the form of a forecast (probability of a future earthquake); a nowcast (knowledge of the current state of an earthquake fault system); or a timecast (statistical estimate of the waiting time until the next major earthquake). In our terminology, a forecast is a model, while the nowcast and timecast are analysis methods using observed data only (no model). We also focus on defined geographic areas rather than on faults, thereby eliminating the need to consider specific fault data or fault interactions. Data used are online earthquake catalogs, generally since 1980. Forecasts are based on the Weibull (1952) probability law, and only a handful of parameters are needed. These methods allow the development of real time hazard and risk estimation using cloud-based technologies, and permit the application of

The HayWired Earthquake Scenario—Earthquake Hazards

Science.gov (United States)

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 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)

Statistics and Analysis of the Relations between Rainstorm Floods and Earthquakes

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Baodeng Hou

2016-01-01

Full Text Available The frequent occurrence of geophysical disasters under climate change has drawn Chinese scholars to pay their attention to disaster relations. If the occurrence sequence of disasters could be identified, long-term disaster forecast could be realized. Based on the Earth Degassing Effect (EDE which is valid, this paper took the magnitude, epicenter, and occurrence time of the earthquake, as well as the epicenter and occurrence time of the rainstorm floods as basic factors to establish an integrated model to study the correlation between rainstorm floods and earthquakes. 2461 severe earthquakes occurred in China or within 3000 km from China and the 169 heavy rainstorm floods occurred in China over the past 200+ years as the input data of the model. The computational results showed that although most of the rainstorm floods have nothing to do with the severe earthquakes from a statistical perspective, some floods might relate to earthquakes. This is especially true when the earthquakes happen in the vapor transmission zone where rainstorms lead to abundant water vapors. In this regard, earthquakes are more likely to cause big rainstorm floods. However, many cases of rainstorm floods could be found after severe earthquakes with a large extent of uncertainty.

Uniform risk functionals for characterization of strong earthquake ground motions

International Nuclear Information System (INIS)

Anderson, J.G.; Trifunac, M.D.

1978-01-01

A uniform risk functional (e.g., Fourier spectrum, response spectrum, duration, etc.) is defined so that the probability that it is exceeded by some earthquake during a selected period of time is independent of the frequency of seismic waves. Such a functional is derived by an independent calculation, at each frequency, for the probability that the quantity being considered will be exceeded. Different aspects of the seismicity can control the amplitude of a uniform risk functional in different frequency ranges, and a uniform risk functional does not necessarily describe the strong shaking from any single earthquake. To be useful for calculating uniform risk functionals, a scaling relationship must provide an independent estimate of amplitudes of the functional in several frequency bands. The scaling relationship of Trifunac (1976) for Fourier spectra satisfies this requirement and further describes the distribution of spectral amplitudes about the mean trend; here, it is applied to find uniform risk Fourier amplitude spectra. In an application to finding the uniform risk spectra at a realistic site, this method is quite sensitive to the description of seismicity. Distinct models of seismicity, all consistent with our current level of knowledge of an area, can give significantly different risk estimates

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

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

The 2016 Kumamoto Earthquakes: Cascading Geological Hazards and Compounding Risks

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Katsuichiro Goda

2016-08-01

Full Text Available A sequence of two strike-slip earthquakes occurred on 14 and 16 April 2016 in the intraplate region of Kyushu Island, Japan, apart from subduction zones, and caused significant damage and disruption to the Kumamoto region. The analyses of regional seismic catalog and available strong motion recordings reveal striking characteristics of the events, such as migrating seismicity, earthquake surface rupture, and major foreshock-mainshock earthquake sequences. To gain valuable lessons from the events, a UK Earthquake Engineering Field Investigation Team (EEFIT was dispatched to Kumamoto, and earthquake damage surveys were conducted to relate observed earthquake characteristics to building and infrastructure damage caused by the earthquakes. The lessons learnt from the reconnaissance mission have important implications on current seismic design practice regarding the required seismic resistance of structures under multiple shocks and the seismic design of infrastructure subject to large ground deformation. The observations also highlight the consequences of cascading geological hazards on community resilience. To share the gathered damage data widely, geo-tagged photos are organized using Google Earth and the kmz file is made publicly available.

“Shake, Rattle and Roll”: risk assessment and management for food safety during two Christchurch earthquakes

Directory of Open Access Journals (Sweden)

Sally Johnston

2012-06-01

Full Text Available Problem: Two earthquakes recently struck the Christchurch region. The 2010 earthquake in Canterbury was strong yet sustained less damage than the 2011 earthquake in Christchurch, which although not as strong, was more damaging and resulted in 185 deaths. Both required activation of a food safety response.Context: The food safety response for both earthquakes was focused on reducing the risk of gastroenteritis by limiting the use of contaminated water and food, both in households and food businesses. Additional food safety risks were identified in the 2011 Christchurch earthquake due the use of large-scale catering for rescue workers, volunteers and residents unable to return home.Action: Using a risk assessment framework, the food safety response involved providing water and food safety advice, issuing a boil water notice for the region and initiating water testing on reticulation systems. Food businesses were contacted to ensure the necessary measures were being taken. Additional action during the 2011 Christchurch earthquake response included making contact with food businesses using checklists and principles developed in the first response and having regular contact with those providing catering for large numbers.Outcome: In the 2010 earthquake in Canterbury, several cases of gastroenteritis were reported, although most resulted from person-to-person contact rather than contamination of food. There was a small increase in gastroenteritis cases following the 2011 Christchurch earthquake.Discussion: The food safety response for both earthquakes was successful in meeting the goal of ensuring that foodborne illness did not put additional pressure on hospitals or affect search and rescue efforts.

Uniform risk spectra of strong earthquake ground motion: NEQRISK

International Nuclear Information System (INIS)

Lee, V.W.; Trifunac, M.D.

1987-01-01

The concept of uniform risk spectra of Anderson and Trifunac (1977) has been generalized to include (1) more refined description of earthquake source zones, (2) the uncertainties in estimating seismicity parameters a and b in log 10 N = a - bM, (3) to consider uncertainties in estimation of maximum earthquake size in each source zone, and to (4) include the most recent results on empirical scaling of strong motion amplitudes at a site. Examples of using to new NEQRISK program are presented and compared with the corresponding case studies of Anderson and Trifunac (1977). The organization of the computer program NEQRISK is also briefly described

Cascading hazards: Understanding triggering relations between wet tropical cyclones, landslides, and earthquakes

Science.gov (United States)

Wdowinski, S.; Peng, Z.; Ferrier, K.; Lin, C. H.; Hsu, Y. J.; Shyu, J. B. H.

2017-12-01

Earthquakes, landslides, and tropical cyclones are extreme hazards that pose significant threats to human life and property. Some of the couplings between these hazards are well known. For example, sudden, widespread landsliding can be triggered by large earthquakes and by extreme rainfall events like tropical cyclones. Recent studies have also shown that earthquakes can be triggered by erosional unloading over 100-year timescales. In a NASA supported project, titled "Cascading hazards: Understanding triggering relations between wet tropical cyclones, landslides, and earthquake", we study triggering relations between these hazard types. The project focuses on such triggering relations in Taiwan, which is subjected to very wet tropical storms, landslides, and earthquakes. One example for such triggering relations is the 2009 Morakot typhoon, which was the wettest recorded typhoon in Taiwan (2850 mm of rain in 100 hours). The typhoon caused widespread flooding and triggered more than 20,000 landslides, including the devastating Hsiaolin landslide. Six months later, the same area was hit by the 2010 M=6.4 Jiashian earthquake near Kaohsiung city, which added to the infrastructure damage induced by the typhoon and the landslides. Preliminary analysis of temporal relations between main-shock earthquakes and the six wettest typhoons in Taiwan's past 50 years reveals similar temporal relations between M≥5 events and wet typhoons. Future work in the project will include remote sensing analysis of landsliding, seismic and geodetic monitoring of landslides, detection of microseismicity and tremor activities, and mechanical modeling of crustal stress changes due to surface unloading.

It's Our Fault: better defining earthquake risk in Wellington, New Zealand

Science.gov (United States)

Van Dissen, R.; Brackley, H. L.; Francois-Holden, C.

2012-12-01

The Wellington region, home of New Zealand's capital city, is cut by a number of major right-lateral strike slip faults, and is underlain by the currently locked west-dipping subduction interface between the down going Pacific Plate, and the over-riding Australian Plate. In its short historic period (ca. 160 years), the region has been impacted by large earthquakes on the strike-slip faults, but has yet to bear the brunt of a subduction interface rupture directly beneath the capital city. It's Our Fault is a comprehensive study of Wellington's earthquake risk. Its objective is to position the capital city of New Zealand to become more resilient through an encompassing study of the likelihood of large earthquakes, and the effects and impacts of these earthquakes on humans and the built environment. It's Our Fault is jointly funded by New Zealand's Earthquake Commission, Accident Compensation Corporation, Wellington City Council, Wellington Region Emergency Management Group, Greater Wellington Regional Council, and Natural Hazards Research Platform. The programme has been running for six years, and key results to date include better definition and constraints on: 1) location, size, timing, and likelihood of large earthquakes on the active faults closest to Wellington; 2) earthquake size and ground shaking characterization of a representative suite of subduction interface rupture scenarios under Wellington; 3) stress interactions between these faults; 4) geological, geotechnical, and geophysical parameterisation of the near-surface sediments and basin geometry in Wellington City and the Hutt Valley; and 5) characterisation of earthquake ground shaking behaviour in these two urban areas in terms of subsoil classes specified in the NZ Structural Design Standard. The above investigations are already supporting measures aimed at risk reduction, and collectively they will facilitate identification of additional actions that will have the greatest benefit towards further

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.

The MCE (Maximum Credible Earthquake) - an approach to reduction of seismic risk

International Nuclear Information System (INIS)

Asmis, G.J.K.; Atchison, R.J.

1979-01-01

It is the responsibility of the Regulatory Body (in Canada, the AECB) to ensure that radiological risks resulting from the effects of earthquakes on nuclear facilities, do not exceed acceptable levels. In simplified numerical terms this means that the frequency of an unacceptable radiation dose must be kept below 10 -6 per annum. Unfortunately, seismic events fall into the class of external events which are not well defined at these low frequency levels. Thus, design earthquakes have been chosen, at the 10 -3 - 10 -4 frequency level, a level commensurate with the limits of statistical data. There exists, therefore, a need to define an additional level of earthquake. A seismic design explicitly and implicitly recognizes three levels of earthquake loading; one comfortably below yield, one at or about yield, and one at ultimate. The ultimate level earthquake, contrary to the first two, has been implicitly addressed by conscientious designers by choosing systems, materials and details compatible with postulated dynamic forces. It is the purpose of this paper to discuss the regulatory specifications required to quantify this third level, or Maximum Credible Earthquake (MCE). (orig.)

Seismic methodology in determining basis earthquake for nuclear installation

International Nuclear Information System (INIS)

Ameli Zamani, Sh.

2008-01-01

Design basis earthquake ground motions for nuclear installations should be determined to assure the design purpose of reactor safety: that reactors should be built and operated to pose no undue risk to public health and safety from earthquake and other hazards. Regarding the influence of seismic hazard to a site, large numbers of earthquake ground motions can be predicted considering possible variability among the source, path, and site parameters. However, seismic safety design using all predicted ground motions is practically impossible. In the determination of design basis earthquake ground motions it is therefore important to represent the influences of the large numbers of earthquake ground motions derived from the seismic ground motion prediction methods for the surrounding seismic sources. Viewing the relations between current design basis earthquake ground motion determination and modem earthquake ground motion estimation, a development of risk-informed design basis earthquake ground motion methodology is discussed for insight into the on going modernization of the Examination Guide for Seismic Design on NPP

Attention bias in earthquake-exposed survivors: an event-related potential study.

Science.gov (United States)

Zhang, Yan; Kong, Fanchang; Han, Li; Najam Ul Hasan, Abbasi; Chen, Hong

2014-12-01

The Chinese Wenchuan earthquake, which happened on the 28th of May in 2008, may leave deep invisible scars in individuals. China has a large number of children and adolescents, who tend to be most vulnerable because they are in an early stage of human development and possible post-traumatic psychological distress may have a life-long consequence. Trauma survivors without post-traumatic stress disorder (PTSD) have received little attention in previous studies, especially in event-related potential (ERP) studies. We compared the attention bias to threat stimuli between the earthquake-exposed group and the control group in a masked version of the dot probe task. The target probe presented at the same space location consistent with earthquake-related words was the congruent trial, while in the space location of neutral words was the incongruent trial. Thirteen earthquake-exposed middle school students without PTSD and 13 matched controls were included in this investigation. The earthquake-exposed group showed significantly faster RTs to congruent trials than to incongruent trials. The earthquake-exposed group produced significantly shorter C1 and P1 latencies and larger C1, P1 and P2 amplitudes than the control group. In particular, enhanced P1 amplitude to threat stimuli was observed in the earthquake-exposed group. These findings are in agreement with the prediction that earthquake-exposed survivors have an attention bias to threat stimuli. The traumatic event had a much greater effect on earthquake-exposed survivors even if they showed no PTSD symptoms than individuals in the controls. These results will provide neurobiological evidences for effective intervention and prevention to post-traumatic mental problems. Copyright © 2014 Elsevier B.V. All rights reserved.

Regional moment: Magnitude relations for earthquakes and explosions

Energy Technology Data Exchange (ETDEWEB)

Patton, H.J.; Walter, W.R. (Lawrence Livermore National Lab., CA (United States))

1993-02-19

The authors present M[sub o]:m[sub b] relations using m[sub b](P[sub n]) and m[sub b](L[sub g]) for earthquakes and explosions occurring in tectonic and stable areas. The observations for m[sub b](P[sub n]) range from about 3 to 6 and show excellent separation between earthquakes and explosions on M[sub o]:m[sub b] plots, independent of the magnitude. The scatter in M[sub o]:M[sub b] observations for NTS explosions is small compared to the earthquake data. The M[sub o]:m[sub b](L[sub g]) data for Soviet explosions overlay the observations for US explosions. These results, and the small scatter for NTS explosions, suggest weak dependence of M[sub o]:m[sub b] relations on emplacement media. A simple theoretical model is developed which matches all these observations. The model uses scaling similarity and conservation of energy to provide a physical link between seismic moment and a broadband seismic magnitude. Three factors, radiation pattern, material property, and apparent stress, contribute to the separation between earthquakes and explosions. This theoretical separation is independent of broadband magnitude. For US explosions in different media, the material property and apparent stress contributions are shown to compensate for one another, supporting the observations that M[sub o]:M[sub b] is nearly independent of source geology. 19 refs., 2 figs., 1 tab.

Earthquake damage to underground facilities and earthquake related displacement fields

International Nuclear Information System (INIS)

Pratt, H.R.; Stephenson, D.E.; Zandt, G.; Bouchon, M.; Hustrulid, W.A.

1982-01-01

The potential seismic risk for an underground facility is considered in the evaluation of its location and design. The possible damage resulting from either large-scale displacements or high accelerations should be considered in evaluating potential sites of underground facilities. Scattered through the available literature are statements to the effect that below a few hundred meters shaking and damage in mines is less than at the surface; however, data for decreased damage underground have not been completely reported or explained. In order to assess the seismic risk for an underground facility, a data base was established and analyzed to evaluate the potential for seismic disturbance. Substantial damage to underground facilities is usually the result of displacements primarily along pre-existing faults and fractures, or at the surface entrance to these facilities. Evidence of this comes from both earthquakes as a function of depth is important in the evaluation of the hazard to underground facilities. To evaluate potential displacements due to seismic effects of block motions along pre-existing or induced fractures, the displacement fields surrounding two types of faults were investigated. Analytical models were used to determine relative displacements of shafts and near-surface displacement of large rock masses. Numerical methods were used to determine the displacement fields associated with pure strike-slip and vertical normal faults. Results are presented as displacements for various fault lengths as a function of depth and distance. This provides input to determine potential displacements in terms of depth and distance for underground facilities, important for assessing potential sites and design parameters

Factors related to furniture anchoring: a method for reducing harm during earthquakes.

Science.gov (United States)

Haraoka, Tomoko; Hayasaka, Shinya; Murata, Chiyoe; Yamaoka, Taiji; Ojima, Toshiyuki

2013-02-01

Fatalities and injuries during an earthquake can be reduced by taking preemptive measures before-hand, and furniture anchoring is an important safety measure for all residents. This study sought to clarify the factors associated with furniture anchoring within the home. A self-administered mail survey was completed from July to August 2010 by 3500 men and women between the ages of 20 and 69 years who were chosen at random from an official government resident registry of 2 cities in Japan. Of the 1729 valid responses, 37.1% reported furniture anchoring. An association with furniture anchoring was observed for having viewed earthquake intensity maps or damage predictions (odds ratio [OR] 1.92, 95% C1 1.54-2.39), expressing concern about a future earthquake (OR 2.07, 95% C1 1.36-3.15), feelings of urgency (OR 1.90, 95% CI 1.47-2.45), accuracy of the government disaster preparedness information (OR 1.68, 95% CI 1.17-2.42), knowledge of the meaning of emergency earthquake warnings (OR 1.67, 95% CI 1.12-2.48), and participation in voluntary disaster preparedness activities (OR 1.40, 95% C1 1.12-1.75). Furniture anchoring was found to be associated with risk awareness, risk perception, disaster preparedness information provided by government to residents, knowledge of earthquakes, participation in voluntary disaster preparedness activities, nonwooden structures, and marital status. An increase in furniture anchoring is important and can be achieved through education and training in daily life.

PRECURSORS OF EARTHQUAKES: VLF SIGNALSIONOSPHERE IONOSPHERE RELATION

Directory of Open Access Journals (Sweden)

Mustafa ULAS

2013-01-01

Full Text Available lot of people have died because of earthquakes every year. Therefore It is crucial to predict the time of the earthquakes reasonable time before it had happed. This paper presents recent information published in the literature about precursors of earthquakes. The relationships between earthquakes and ionosphere are targeted to guide new researches in order to study further to find novel prediction methods.

Human Trafficking in Nepal: Post-Earthquake Risk and Response.

Science.gov (United States)

Gyawali, Bishal; Keeling, June; Kallestrup, Per

2017-04-01

As Nepal mourns the 1-year commemoration of the April 2015 earthquake and its aftershocks that killed more than 8500 people and left thousands injured and displaced, other more hidden repercussions of the resultant chaotic environment need attention: the increased risk of human trafficking. Considering that natural disasters provide a milieu for this illicit trade, there is a need for a robust response from stakeholders such as donors, civil society organizations, and government organizations against human trafficking following disasters such as the Nepal earthquake. Responsibility to prevent and fight trafficking should be explicitly included in the mandate of relief and rehabilitation mechanisms set up at the national level to coordinate the disaster relief response, serving to support populations in both rural and urban areas. (Disaster Med Public Health Preparedness. 2017;11:153-154).

Tectonic Movement in Korean Peninsula and Relation between Fault and Earthquake

International Nuclear Information System (INIS)

Bae, Dae Seok; Koh, Yong Kwon; Kim, Kyung Su

2009-08-01

The objectives of the research are to study geological faults and related geological processes such as tectonic processes and earthquake to select a safe site for the high level radioactive waste disposal consequently. The results from this study show the significance of faults evaluation and develop methods to analyze geological data related to faults such as tectonic processes and earthquake, which are important data for the site selection

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)

LastQuake: a comprehensive strategy for rapid engagement of earthquake eyewitnesses, massive crowdsourcing and risk reduction

Science.gov (United States)

Bossu, R.; Roussel, F.; Mazet-Roux, G.; Steed, R.; Frobert, L.

2015-12-01

LastQuake is a smartphone app, browser add-on and the most sophisticated Twitter robot (quakebot) for earthquakes currently in operation. It fulfills eyewitnesses' needs by offering information on felt earthquakes and their effects within tens of seconds of their occurrence. Associated with an active presence on Facebook, Pinterest and on websites, this proves a very efficient engagement strategy. For example, the app was installed thousands of times after the Ghorka earthquake in Nepal. Language barriers have been erased by using visual communication; for example, felt reports are collected through a set of cartoons representing different shaking levels. Within 3 weeks of the magnitude 7.8 Ghorka earthquakes, 7,000 felt reports with thousands of comments were collected related to the mainshock and tens of its aftershocks as well as 100 informative geo-located pics. The QuakeBot was essential in allowing us to be identified so well and interact with those affected. LastQuake is also a risk reduction tool since it provides rapid information. Rapid information is similar to prevention since when it does not exist, disasters can happen. When no information is available after a felt earthquake, the public block emergency lines by trying to find out the cause of the shaking, crowds form potentially leading to unpredictable crowd movement, rumors spread. In its next release LastQuake will also provide people with guidance immediately after a shaking through a number of pop-up cartoons illustrating "do/don't do" items (go to open places, do not phone emergency services except if people are injured…). LastQuake's app design is simple and intuitive and has a global audience. It benefited from a crowdfunding campaign (and the support of the Fondation MAIF) and more improvements have been planned after an online feedback campaign organized in early June with the Ghorka earthquake eyewitnesses. LastQuake is also a seismic risk reduction tools thanks to its very rapid

Fleeing to Fault Zones: Incorporating Syrian Refugees into Earthquake Risk Analysis along the East Anatolian and Dead Sea Rift Fault Zones

Science.gov (United States)

Wilson, B.; Paradise, T. R.

2016-12-01

The influx of millions of Syrian refugees into Turkey has rapidly changed the population distribution along the Dead Sea Rift and East Anatolian Fault zones. In contrast to other countries in the Middle East where refugees are accommodated in camp environments, the majority of displaced individuals in Turkey are integrated into cities, towns, and villages—placing stress on urban settings and increasing potential exposure to strong shaking. Yet, displaced populations are not traditionally captured in data sources used in earthquake risk analysis or loss estimations. Accordingly, we present a district-level analysis assessing the spatial overlap of earthquake hazards and refugee locations in southeastern Turkey to determine how migration patterns are altering seismic risk in the region. Using migration estimates from the U.S. Humanitarian Information Unit, we create three district-level population scenarios that combine official population statistics, refugee camp populations, and low, median, and high bounds for integrated refugee populations. We perform probabilistic seismic hazard analysis alongside these population scenarios to map spatial variations in seismic risk between 2011 and late 2015. Our results show a significant relative southward increase of seismic risk for this period due to refugee migration. Additionally, we calculate earthquake fatalities for simulated earthquakes using a semi-empirical loss estimation technique to determine degree of under-estimation resulting from forgoing migration data in loss modeling. We find that including refugee populations increased casualties by 11-12% using median population estimates, and upwards of 20% using high population estimates. These results communicate the ongoing importance of placing environmental hazards in their appropriate regional and temporal context which unites physical, political, cultural, and socio-economic landscapes. Keywords: Earthquakes, Hazards, Loss-Estimation, Syrian Crisis, Migration

Relating stick-slip friction experiments to earthquake source parameters

Science.gov (United States)

McGarr, Arthur F.

2012-01-01

Analytical results for parameters, such as static stress drop, for stick-slip friction experiments, with arbitrary input parameters, can be determined by solving an energy-balance equation. These results can then be related to a given earthquake based on its seismic moment and the maximum slip within its rupture zone, assuming that the rupture process entails the same physics as stick-slip friction. This analysis yields overshoots and ratios of apparent stress to static stress drop of about 0.25. The inferred earthquake source parameters static stress drop, apparent stress, slip rate, and radiated energy are robust inasmuch as they are largely independent of the experimental parameters used in their estimation. Instead, these earthquake parameters depend on C, the ratio of maximum slip to the cube root of the seismic moment. C is controlled by the normal stress applied to the rupture plane and the difference between the static and dynamic coefficients of friction. Estimating yield stress and seismic efficiency using the same procedure is only possible when the actual static and dynamic coefficients of friction are known within the earthquake rupture zone.

Facilitation of intermediate-depth earthquakes by eclogitization-related stresses and H2O

Science.gov (United States)

Nakajima, J.; Uchida, N.; Hasegawa, A.; Shiina, T.; Hacker, B. R.; Kirby, S. H.

2012-12-01

Generation of intermediate-depth earthquakes is an ongoing enigma because high lithostatic pressures render ordinary dry frictional failure unlikely. A popular hypothesis to solve this conundrum is fluid-related embrittlement (e.g., Kirby et al., 1996; Preston et al., 2003), which is known to work even for dehydration reactions with negative volume change (Jung et al., 2004). One consequence of reaction with the negative volume change is the formation of a paired stress field as a result of strain compatibility across the reaction front (Hacker, 1996; Kirby et al., 1996). Here we analyze waveforms of a tiny seismic cluster in the lower crust of the downgoing Pacific plate at a depth of 155 km and propose new evidence in favor of this mechanism: tensional earthquakes lying 1 km above compressional earthquakes, and earthquakes with highly similar waveforms lying on well-defined planes with complementary rupture areas. The tensional stress is interpreted to be caused by the dimensional mismatch between crust transformed to eclogite and underlying untransformed crust, and the earthquakes are interpreted to be facilitated by fluid produced by eclogitization. These observations provide seismic evidence for the dual roles of volume-change related stresses and fluid-related embrittlement as viable processes for nucleating earthquakes in downgoing oceanic lithosphere.

Collapse risk of buildings in the Pacific Northwest region due to subduction earthquakes

Science.gov (United States)

Raghunandan, Meera; Liel, Abbie B.; Luco, Nicolas

2015-01-01

Subduction earthquakes similar to the 2011 Japan and 2010 Chile events will occur in the future in the Cascadia subduction zone in the Pacific Northwest. In this paper, nonlinear dynamic analyses are carried out on 24 buildings designed according to outdated and modern building codes for the cities of Seattle, Washington, and Portland, Oregon. The results indicate that the median collapse capacity of the ductile (post-1970) buildings is approximately 40% less when subjected to ground motions from subduction, as compared to crustal earthquakes. Buildings are more susceptible to earthquake-induced collapse when shaken by subduction records (as compared to crustal records of the same intensity) because the subduction motions tend to be longer in duration due to their larger magnitude and the greater source-to-site distance. As a result, subduction earthquakes are shown to contribute to the majority of the collapse risk of the buildings analyzed.

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

Measuring the effectiveness of earthquake forecasting in insurance strategies

Science.gov (United States)

Mignan, A.; Muir-Wood, R.

2009-04-01

Given the difficulty of judging whether the skill of a particular methodology of earthquake forecasts is offset by the inevitable false alarms and missed predictions, it is important to find a means to weigh the successes and failures according to a common currency. Rather than judge subjectively the relative costs and benefits of predictions, we develop a simple method to determine if the use of earthquake forecasts can increase the profitability of active financial risk management strategies employed in standard insurance procedures. Three types of risk management transactions are employed: (1) insurance underwriting, (2) reinsurance purchasing and (3) investment in CAT bonds. For each case premiums are collected based on modelled technical risk costs and losses are modelled for the portfolio in force at the time of the earthquake. A set of predetermined actions follow from the announcement of any change in earthquake hazard, so that, for each earthquake forecaster, the financial performance of an active risk management strategy can be compared with the equivalent passive strategy in which no notice is taken of earthquake forecasts. Overall performance can be tracked through time to determine which strategy gives the best long term financial performance. This will be determined by whether the skill in forecasting the location and timing of a significant earthquake (where loss is avoided) is outweighed by false predictions (when no premium is collected). This methodology is to be tested in California, where catastrophe modeling is reasonably mature and where a number of researchers issue earthquake forecasts.

From Seismic Scenarios to Earthquake Risk Assessment: A Case Study for Iquique, Chile.

Science.gov (United States)

Aguirre, P.; Fortuno, C.; Martin, J. C. D. L. L.; Vasquez, J.

2015-12-01

Iquique is a strategic city and economic center in northern Chile, and is located in a large seismic gap where a megathrust earthquake and tsunami is expected. Although it was hit by a Mw 8.2 earthquake on April 1st 2014, which caused moderate damage, geophysical evidence still suggests that there is potential for a larger event, so a thorough risk assessment is key to understand the physical, social, and economic effects of such potential event, and devise appropriate mitigation plans. Hence, Iquique has been selected as a prime study case for the implementation of a risk assessment platform in Chile. Our study integrates research on three main elements of risk calculations: hazard evaluation, exposure model, and physical vulnerabilities. To characterize the hazard field, a set of synthetic seismic scenarios have been developed based on plate interlocking and the residual slip potential that results from subtracting the slip occurred during the April 1st 2014 rupture fault mechanism, obtained using InSAR+GPS inversion. Additional scenarios were developed based of the fault rupture model of the Maule 2010 Mw 8.8 earthquake and on the local plate locking models in northern Chile. These rupture models define a collection of possible realizations of earthquake geometries parameterized in terms of critical variables like slip magnitude, rise time, mean propagation velocity, directivity, and other, which are propagated to obtain a hazard map for Iquique (e.g. PGA, PGV, PDG). Furthermore, a large body of public and local data was used to construct a detailed exposure model for Iquique, including aggregated building count, demographics, essential facilities, and lifelines. This model together with the PGA maps for the April 1st 2014 earthquake are used to calibrate HAZUS outputs against observed damage, and adjust the fragility curves of physical systems according to more detailed analyses of typical Chilean building types and their structural properties, plus historical

Earthquakes in the kindergarten educate for risk mitigation

Science.gov (United States)

Mata, Isabel; Rodrigues, Isabel; Matias, Luis

2016-04-01

"Earthquakes in the kindergarten educate for risk mitigation" Isabel Rodrigues, Jardim de Infância D. Dinis, Odivelas, Isabel Mata, Secondary School Adelaide Cabette, Odivelas Luis Matias (UL / IDL), Instituto Dom Luiz, Universityof Lisbon, Lisbon, Portugal In Portugal Education for risk is now recognized as a child training component and young learners should develop the right skills in the first years of life. School can have an important role in this process, as a privileged actor in the mobilization of every society, providing and promoting dynamic and educational practices aimed at the wider spectrum of education for citizenship, the adoption of safety behaviours, prevention and adequate management of risk. The Group of Schools Adelaide Cabette in Odivelas is now a set of schools, from Kindergarten to Secondary. Aiming at educating for risk prevention, we developed an experiment with a pre-school class directed to the seismic risk, which was extended to Earth Sciences because it is difficult to teach this topic to the youngest learners, either from Kindergarten or from Primary School, as they haven't learned enough about planet Earth (many don't even know that it is not flat but round like a ball). This experiment involved a working project 1, which was initially developed in one of the classrooms, in kindergarten D. Dinis, and many questions have been asked by the students. The explanation for the students' questions gave origin to a set of experiences developed in the Secondary school. The same class concluded the project in their own classroom. In this project the young learners could have contact with pre-school teachers, secondary and university researchers, thus promoting the sharing of different knowledge, including the scientific linked to the educational one. We would like to share our poster summarizing our experience which we feltwas not only a great challenge, but also a rewarding way to disseminate science to the youngest learners. 1. Keywords

Development of fire risk assessment method caused by earthquake

International Nuclear Information System (INIS)

Mitomo, Nobuo; Matsukura, Hiroshi; Matsuoka, Takeshi; Suzuki, Kazutaka

2000-01-01

The purpose of this research is to establish the assessment method of the risk of the multiple fires caused by earthquake, in the framework of PSA. In order to establish this method, we have settled four tasks and started a five years research project in 1999 for five years. These results will be useful for not only nuclear power plants but also chemical plants, traffic systems etc. (author)

Investigation of the ULF electromagnetic phenomena related to earthquakes. Contemporary achievements and the perspectives

Energy Technology Data Exchange (ETDEWEB)

Kopytenko, Y.; Ismagilov, V. [SPbF Izmiran, St. Petersbourg (Russian Federation); Hayakawa, M [The University of Electro-Communications, Chofu, Tokyo (Japan); Smirnova, N.; Troyan, V. [St. Petersbourg Univ., St Petersbourg (Russian Federation). Inst. of Physics; Peterson, T. [TFPLAB, Cleveland, OH (United States)

2001-04-01

The results of ULF electromagnetic signal observations in seismoactive regions prior to earthquakes are presented and discussed. The new differential measurement technique developed in SPbF IZMIRAN for location of the ULF emission sources of space and lithosphere origin is described. The MVC-2DS geohphysical instrumentation is introduced as a promising tool for registration of ULF signals related to earthquakes (both seismic and electromagnetic ones). Methods are proposed for ULF data processing to investigate the preparation processes in the earthquake source regions and to distinguish seismogenic signals. on the background of space pulsations. Some examples of application of those methods for study of the earthquake precursory signatures are presented. Perspectives of seismo-electromagnetic tomography experiments in seismoactive regions, using MVC-2DS technique, are discussed in relation to the development of earthquake prediction methods.

Magnetic storm free ULF analysis in relation with earthquakes in Taiwan

Directory of Open Access Journals (Sweden)

S. Wen

2012-05-01

Full Text Available Despite early optimism, pre-earthquake anomalous phenomena can be determined by using enhanced amplitude at the ultra-low-frequency range from geomagnetic data via the Fourier transform. In reality, accuracy of the enhanced amplitude in relation to earthquakes (deduced from time-varied geomagnetic data would be damaged by magnetic storms and/or other unwanted influences resulting from solar activity and/or variations in the ionosphere, respectively. We substitute values of the cross correlation between amplitudes, summarized from the earthquake-related (0.1–0.01 Hz and the comparable (0.01–0.001 Hz frequency bands, for isolated amplitude enhancements as indexes of determination associated with seismo-magnetic anomalies to mitigate disturbance caused by magnetic storms. A station located about 300 km away from the others is also taken into account to further examine whether changes of the cross correlation values are caused by seismo-magnetic anomalies limited within local regions or not. Analytical results show that the values suddenly decrease near epicenters a few days before and after 67% (= 6/9 of earthquakes (M > = 5 in Taiwan between September 2010 and March 2011. Seismo-magnetic signals determined by using the values of cross correlation methods partially improve results yielded from the Fourier transform alone and provide advantageous information of earthquake locations.

Earthquake data base for Romania

International Nuclear Information System (INIS)

Rizescu, M.; Ghica, D.; Grecu, B.; Popa, M.; Borcia, I. S.

2002-01-01

A new earthquake database for Romania is being constructed, comprising complete earthquake information and being up-to-date, user-friendly and rapidly accessible. One main component of the database consists from the catalog of earthquakes occurred in Romania since 984 up to present. The catalog contains information related to locations and other source parameters, when available, and links to waveforms of important earthquakes. The other very important component is the 'strong motion database', developed for strong intermediate-depth Vrancea earthquakes where instrumental data were recorded. Different parameters to characterize strong motion properties as: effective peak acceleration, effective peak velocity, corner periods T c and T d , global response spectrum based intensities were computed and recorded into this database. Also, information on the recording seismic stations as: maps giving their positioning, photographs of the instruments and site conditions ('free-field or on buildings) are included. By the huge volume and quality of gathered data, also by its friendly user interface, the Romania earthquake data base provides a very useful tool for geosciences and civil engineering in their effort towards reducing seismic risk in Romania. (authors)

Earthquake related dynamic groundwater pressure changes observed at the Kamaishi Mine

International Nuclear Information System (INIS)

Sasaki, Shunji; Yasuike, Shinji; Komada, Hiroya; Kobayashi, Yoshimasa; Kawamura, Makoto; Aoki, Kazuhiro

1999-01-01

From 342 seismic records observed at the Kamaishi Mine form 1990 to 1998, a total of 92 data whose acceleration is greater than 1 gal or ground water pressure is greater than 1 kPa were selected and dynamic ground water pressure changes associated with earthquakes were studied. The results obtained are as follows: (1) A total of 27 earthquakes accompanied by static ground water pressure changes were observed. Earthquake-related static ground water pressure changes are smaller than 1/10 of the annual range of ground water pressure changes. There is also a tendency that the ground water pressure changes recovers to its original trend in several weeks after earthquakes. (2) Dynamic ground water pressure changes associated with earthquakes occur when P-waves arrive. However, the largest dynamic ground water pressure changes occur on S-wave part arrivals where the amplitude of seismic wave is the largest. A positive correlation is recognized between the maximum value of velocity wave form and that of dynamic ground water pressure changes. (3) The characteristic of dynamic change in ground water pressure due to earthquakes can be explained qualitatively by mechanism in which the P-wave converted from an incident SV wave propagates along the borehole. (author)

[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.

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.

Change of risk information disclosure in annual report. Before and after earthquake disaster

International Nuclear Information System (INIS)

Ueno, Takefumi

2011-01-01

This research examines how risk information disclosure is changing in annual report before and after East Japan Great Earthquake Disaster. Company voluntary disclose risk information in annual report. Manager can decide a style and items of risk information. This paper explores risk information disclosures of Tokyo Electric Power Company, Chubu Power Electric Company, Kansai Electric Power Company and Toyota Motor Corporation. The managers except Tokyo Electric Company are likely to disclose own catastrophe risk before the disaster. However, they do not try to reduce their risk. Corporations' risk information do not link with own risk management. (author)

Dynamic evaluation of seismic hazard and risks based on the Unified Scaling Law for Earthquakes

Science.gov (United States)

Kossobokov, V. G.; Nekrasova, A.

2016-12-01

We continue applying the general concept of seismic risk analysis in a number of seismic regions worldwide by constructing seismic hazard maps based on the Unified Scaling Law for Earthquakes (USLE), i.e. log N(M,L) = A + B•(6 - M) + C•log L, where N(M,L) is the expected annual number of earthquakes of a certain magnitude M within an seismically prone area of linear dimension L, A characterizes the average annual rate of strong (M = 6) earthquakes, B determines the balance between magnitude ranges, and C estimates the fractal dimension of seismic locus in projection to the Earth surface. The parameters A, B, and C of USLE are used to assess, first, the expected maximum magnitude in a time interval at a seismically prone cell of a uniform grid that cover the region of interest, and then the corresponding expected ground shaking parameters. After a rigorous testing against the available seismic evidences in the past (e.g., the historically reported macro-seismic intensity or paleo data), such a seismic hazard map is used to generate maps of specific earthquake risks for population, cities, and infrastructures. The hazard maps for a given territory change dramatically, when the methodology is applied to a certain size moving time window, e.g. about a decade long for an intermediate-term regional assessment or exponentially increasing intervals for a daily local strong aftershock forecasting. The of dynamical seismic hazard and risks assessment is illustrated by applications to the territory of Greater Caucasus and Crimea and the two-year series of aftershocks of the 11 October 2008 Kurchaloy, Chechnya earthquake which case-history appears to be encouraging for further systematic testing as potential short-term forecasting tool.

Hazus® estimated annualized earthquake losses for the United States

Science.gov (United States)

Jaiswal, Kishor; Bausch, Doug; Rozelle, Jesse; Holub, John; McGowan, Sean

2017-01-01

Large earthquakes can cause social and economic disruption that can be unprecedented to any given community, and the full recovery from these impacts may or may not always be achievable. In the United States (U.S.), the 1994 M6.7 Northridge earthquake in California remains the third costliest disaster in U.S. history; and it was one of the most expensive disasters for the federal government. Internationally, earthquakes in the last decade alone have claimed tens of thousands of lives and caused hundreds of billions of dollars of economic impact throughout the globe (~90 billion U.S. dollars (USD) from 2008 M7.9 Wenchuan China, ~20 billion USD from 2010 M8.8 Maule earthquake in Chile, ~220 billion USD from 2011 M9.0 Tohoku Japan earthquake, ~25 billion USD from 2011 M6.3 Christchurch New Zealand, and ~22 billion USD from 2016 M7.0 Kumamoto Japan). Recent earthquakes show a pattern of steadily increasing damages and losses that are primarily due to three key factors: (1) significant growth in earthquake-prone urban areas, (2) vulnerability of the older building stock, including poorly engineered non-ductile concrete buildings, and (3) an increased interdependency in terms of supply and demand for the businesses that operate among different parts of the world. In the United States, earthquake risk continues to grow with increased exposure of population and development even though the earthquake hazard has remained relatively stable except for the regions of induced seismic activity. Understanding the seismic hazard requires studying earthquake characteristics and locales in which they occur, while understanding the risk requires an assessment of the potential damage from earthquake shaking to the built environment and to the welfare of people—especially in high-risk areas. Estimating the varying degree of earthquake risk throughout the United States is critical for informed decision-making on mitigation policies, priorities, strategies, and funding levels in the

Integrated Earthquake Risk Assessment in the Kathmandu Valley - A Case Study

Science.gov (United States)

Schaper, Julia; Anhorn, Johannes; Khazai, Bijan; Nüsser, Marcus

2013-04-01

Rapid urban growth is a process which can be observed in cities worldwide. Managing these growing urban areas has become a major challenge for both governing bodies and citizens. Situated not only in a highly earthquake and landslide-prone area, but comprising also the cultural and political capital of Nepal, the fast expanding Kathmandu Valley in the Himalayan region is of particular interest. Vulnerability assessment has been an important tool for spatial planning in this already densely populated area. The magnitude 8.4 earthquake of Bihar in 1934 cost 8600 Nepalis their lives, destroyed 20% of the Kathmandu building stock and heavily damaged another 40%. Since then, Kathmandu has grown into a hub with over a million inhabitants. Rapid infrastructure and population growth aggravate the vulnerability conditions, particularly in the core area of Metropolitan Kathmandu. We propose an integrative framework for vulnerability and risk in Kathmandu Valley. In order to move towards a more systemic and integrated approach, we focus on interactions between natural hazards, physically engineered systems and society. High resolution satellite images are used to identify structural vulnerability of the building stock within the study area. Using object-based image analysis, the spatial dynamics of urban growth are assessed and validated using field data. Complementing this is the analysis of socio-economic attributes gained from databases and field surveys. An indicator-based vulnerability and resilience index will be operationalized using multi-attribute value theory and statistical methods such as principal component analysis. The results allow for a socio-economic comparison of places and their relative potential for harm and loss. The objective in this task is to better understand the interactions between nature and society, engineered systems and built environments through the development of an interdisciplinary framework on systemic seismic risk and vulnerability. Data

Developing Effective Earthquake Risk Reduction Strategies: The Potential Role of Academic Institutions in Lebanon

Science.gov (United States)

Baytiyeh, Hoda

2015-01-01

Lebanon faces the risk of powerful earthquakes with potentially devastating effects. However, the Lebanese people in general have not yet recognized this risk, as current educational programs and government officials have failed to inform them about it. This article discusses the essential role that Lebanese institutions of higher education should…

Earthquake Loss Assessment for the Evaluation of the Sovereign Risk and Financial Sustainability of Countries and Cities

Science.gov (United States)

Cardona, O. D.

2013-05-01

Recently earthquakes have struck cities both from developing as well as developed countries, revealing significant knowledge gaps and the need to improve the quality of input data and of the assumptions of the risk models. The quake and tsunami in Japan (2011) and the disasters due to earthquakes in Haiti (2010), Chile (2010), New Zealand (2011) and Spain (2011), only to mention some unexpected impacts in different regions, have left several concerns regarding hazard assessment as well as regarding the associated uncertainties to the estimation of the future losses. Understanding probable losses and reconstruction costs due to earthquakes creates powerful incentives for countries to develop planning options and tools to cope with sovereign risk, including allocating the sustained budgetary resources necessary to reduce those potential damages and safeguard development. Therefore the use of robust risk models is a need to assess the future economic impacts, the country's fiscal responsibilities and the contingent liabilities for governments and to formulate, justify and implement risk reduction measures and optimal financial strategies of risk retention and transfer. Special attention should be paid to the understanding of risk metrics such as the Loss Exceedance Curve (empiric and analytical) and the Expected Annual Loss in the context of conjoint and cascading hazards.

Using Spatial Multi-Criteria Analysis and Ranking Tool (SMART in earthquake risk assessment: a case study of Delhi region, India

Directory of Open Access Journals (Sweden)

Nishant Sinha

2016-03-01

Full Text Available This article is aimed at earthquake hazard, vulnerability and risk assessment as a case study to demonstrate the applicability of Spatial Multi-Criteria Analysis and Ranking Tool (SMART, which is based on Saaty's multi-criteria decision analysis (MCDA technique. The three specific study sites of Delhi were chosen for research as it corresponds to a typical patch of the urban environs, completely engrossed with residential, commercial and industrial units. The earthquake hazard affecting components are established in the form of geographic information system data-set layers including seismic zone, peak ground acceleration (PGA, soil characteristics, liquefaction potential, geological characteristics, land use, proximity to fault and epicentre. The physical vulnerability layers comprising building information, namely number of stories, year-built range, area, occupancy and construction type, derived from remote sensing imagery, were only considered for the current research. SMART was developed for earthquake risk assessment, and weights were derived both at component and its element level. Based on weighted overlay techniques, the earthquake hazard and vulnerability layers were created from which the risk maps were derived through multiplicative analysis. The developed risk maps may prove useful in decision-making process and formulating risk mitigation measures.

Statistical distributions of earthquakes and related non-linear features in seismic waves

International Nuclear Information System (INIS)

Apostol, B.-F.

2006-01-01

A few basic facts in the science of the earthquakes are briefly reviewed. An accumulation, or growth, model is put forward for the focal mechanisms and the critical focal zone of the earthquakes, which relates the earthquake average recurrence time to the released seismic energy. The temporal statistical distribution for average recurrence time is introduced for earthquakes, and, on this basis, the Omori-type distribution in energy is derived, as well as the distribution in magnitude, by making use of the semi-empirical Gutenberg-Richter law relating seismic energy to earthquake magnitude. On geometric grounds, the accumulation model suggests the value r = 1/3 for the Omori parameter in the power-law of energy distribution, which leads to β = 1,17 for the coefficient in the Gutenberg-Richter recurrence law, in fair agreement with the statistical analysis of the empirical data. Making use of this value, the empirical Bath's law is discussed for the average magnitude of the aftershocks (which is 1.2 less than the magnitude of the main seismic shock), by assuming that the aftershocks are relaxation events of the seismic zone. The time distribution of the earthquakes with a fixed average recurrence time is also derived, the earthquake occurrence prediction is discussed by means of the average recurrence time and the seismicity rate, and application of this discussion to the seismic region Vrancea, Romania, is outlined. Finally, a special effect of non-linear behaviour of the seismic waves is discussed, by describing an exact solution derived recently for the elastic waves equation with cubic anharmonicities, its relevance, and its connection to the approximate quasi-plane waves picture. The properties of the seismic activity accompanying a main seismic shock, both like foreshocks and aftershocks, are relegated to forthcoming publications. (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

Earthquake risk reduction in the United States: An assessment of selected user needs and recommendations for the National Earthquake Hazards Reduction Program

Energy Technology Data Exchange (ETDEWEB)

NONE

1994-12-31

This Assessment was conducted to improve the National Earthquake Hazards Reduction Program (NEHRP) by providing NEHRP agencies with information that supports their user-oriented setting of crosscutting priorities in the NEHRP strategic planning process. The primary objective of this Assessment was to take a ``snapshot`` evaluation of the needs of selected users throughout the major program elements of NEHRP. Secondary objectives were to conduct an assessment of the knowledge that exists (or is being developed by NEHRP) to support earthquake risk reduction, and to begin a process of evaluating how NEHRP is meeting user needs. An identification of NEHRP`s strengths also resulted from the effort, since those strengths demonstrate successful methods that may be useful to NEHRP in the future. These strengths are identified in the text, and many of them represent important achievements since the Earthquake Hazards Reduction Act was passed in 1977.

Evaluation on lifetime risk in reinforced concrete structure; RC kozo no lifetime risk no hyoka ni kansuru kisoteki kenkyu

Energy Technology Data Exchange (ETDEWEB)

Suzuki, M. [Public Works Research Institute, Tsukuba (Japan); Adachi, H. [Taisei Corp., Tokyo (Japan); Akakura, Y. [Ministry of Transport, Tokyo (Japan); Ibayashi, K.; Ozaka, Y. [Tohoku Gakuin Univ., Sendai (Japan)

1996-02-15

To evaluate the risk during longevity of reinforced concrete structure subjected to earthquake motions, called lifetime risk, damage and safety were estimated by means of the earthquake risk analysis and earthquake response analysis. For the earthquake risk analysis, historical earthquake data with relatively low accuracy were efficiently taken into account, to determine the annual mean generation probability against the earthquake motion strength in ten main cities. A new damage index with load hysteresis was defined as an anti-earthquake evaluation index where accumulative damage is taken into consideration. Assuming that the damage transits from `certain state` to `certain state` every time the earthquake motion generates at the noticeable place, damage transition matrix expressing transition probability was calculated by using the results of earthquake risk analysis and the accumulative damage index. The lifetime risk was calculated from the damage transition matrix and the earthquake motion generation probability, to evaluate the safety. 21 refs., 10 figs., 8 tabs.

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

Science.gov (United States)

Larroque, Christophe; Ioualalen, Mansour; Scotti, Oona

2014-05-01

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

Risk factors for malnutrition in under-five children: one year after the Yogyakarta earthquake

Directory of Open Access Journals (Sweden)

Neti Nurani

2011-12-01

Full Text Available Background Malnutrition in children under the age of five remains a major health problem, since half of mortality cases in this age group involve malnutrition. The 2006 earthquake caused destruction of physical, biological and socio-economic environments, potentially leading to malnutrition in Yogyakarta children. Objective To identify the prevalence and risk factors of malnutrition in Yogyakarta children under five years of age, one year after the 2006 earthquake. Methods We conducted a cross-sectional study among children aged 0 to 60 months in the Bambanglipuro Subdistrict, Bantul Regency, Yogyakarta from September to October 2007. Nutritional status was determined using weight for height Z-scores, according to the WHO 2006 Child Growth Standards. Results Out of 666 subjects, we found severe malnutrition, undernutrition, normal weight, and overweight status in 1.7%, 4.8%, 88.6% and 4.8%, respectively. By multivariate analysis, risk factors for malnutrition were not having been weighed during the previous three months (OR 0.35; 95% CI 0.1 to 0.8 and having acute respiratory infection in the previous two weeks (OR 1.99; 95% CI 1.1 to 3.8 Conclusion One year following the 2006 earthquake, acute respiratory infection in the previous two weeks and unmonitored growth in the previous three months were risk factors for malnutrition in children under five years.

Keeping focus on earthquakes at school for seismic risk mitigation of the next generations

Science.gov (United States)

Saraò, Angela; Barnaba, Carla; Peruzza, Laura

2013-04-01

The knowledge of the seismic history of its own territory, the understanding of physical phenomena in response to an earthquake, the changes in the cultural heritage following a strong earthquake, the learning of actions to be taken during and after an earthquake, are piece of information that contribute to keep focus on the seismic hazard and to implement strategies for seismic risk mitigation. The training of new generations, today more than ever subject to rapid forgetting of past events, becomes therefore a key element to increase the perception that earthquakes happened and can happen at anytime and that mitigation actions are the only means to ensure the safety and to reduce damages and human losses. Since several years our institute (OGS) is involved in activities to raise awareness of education on earthquake. We aim to implement education programs with the goal of addressing a critical approach to seismic hazard reduction, differentiating the types of activities according to the age of the students. However, being such kind of activity unfunded, we can act at now only on a very limited number of schools per year. To be effective, the inclusion of the seismic risk issues in school curricula requires specific time and appropriate approaches when planning activities. For this reason, we involve also the teachers as proponents of activities and we encourage them to keep alive memories and discussion on earthquake in the classes. During the past years we acted mainly in the schools of the Friuli Venezia Giulia area (NE Italy), that is an earthquake prone area struck in 1976 by a destructive seismic event (Ms=6.5). We organized short training courses for teachers, we lectured classes, and we led laboratory activities with students. Indeed, being well known that students enjoy classes more when visual and active learning are joined, we propose a program that is composed by seminars, demonstrations and hands-on activities in the classrooms; for high school students

Modeling, Forecasting and Mitigating Extreme Earthquakes

Science.gov (United States)

Ismail-Zadeh, A.; Le Mouel, J.; Soloviev, A.

2012-12-01

Recent earthquake disasters highlighted the importance of multi- and trans-disciplinary studies of earthquake risk. A major component of earthquake disaster risk analysis is hazards research, which should cover not only a traditional assessment of ground shaking, but also studies of geodetic, paleoseismic, geomagnetic, hydrological, deep drilling and other geophysical and geological observations together with comprehensive modeling of earthquakes and forecasting extreme events. Extreme earthquakes (large magnitude and rare events) are manifestations of complex behavior of the lithosphere structured as a hierarchical system of blocks of different sizes. Understanding of physics and dynamics of the extreme events comes from observations, measurements and modeling. A quantitative approach to simulate earthquakes in models of fault dynamics will be presented. The models reproduce basic features of the observed seismicity (e.g., the frequency-magnitude relationship, clustering of earthquakes, occurrence of extreme seismic events). They provide a link between geodynamic processes and seismicity, allow studying extreme events, influence of fault network properties on seismic patterns and seismic cycles, and assist, in a broader sense, in earthquake forecast modeling. Some aspects of predictability of large earthquakes (how well can large earthquakes be predicted today?) will be also discussed along with possibilities in mitigation of earthquake disasters (e.g., on 'inverse' forensic investigations of earthquake disasters).

Crowdsourced earthquake early warning

Science.gov (United States)

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

2015-01-01

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

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

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.

Correlation between Earthquakes and AE Monitoring of Historical Buildings in Seismic Areas

Directory of Open Access Journals (Sweden)

Giuseppe Lacidogna

2015-12-01

Full Text Available In this contribution a new method for evaluating seismic risk in regional areas based on the acoustic emission (AE technique is proposed. Most earthquakes have precursors, i.e., phenomena of changes in the Earth’s physical-chemical properties that take place prior to an earthquake. Acoustic emissions in materials and earthquakes in the Earth’s crust, despite the fact that they take place on very different scales, are very similar phenomena; both are caused by a release of elastic energy from a source located in a medium. For the AE monitoring, two important constructions of Italian cultural heritage are considered: the chapel of the “Sacred Mountain of Varallo” and the “Asinelli Tower” of Bologna. They were monitored during earthquake sequences in their relative areas. By using the Grassberger-Procaccia algorithm, a statistical method of analysis was developed that detects AEs as earthquake precursors or aftershocks. Under certain conditions it was observed that AEs precede earthquakes. These considerations reinforce the idea that the AE monitoring can be considered an effective tool for earthquake risk evaluation.

Earthquake Hazard Analysis Methods: A Review

Science.gov (United States)

Sari, A. M.; Fakhrurrozi, A.

2018-02-01

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

Earthquake modelling at the country level using aggregated spatio-temporal point processes

NARCIS (Netherlands)

Lieshout, van M.N.M.; Stein, A.

2011-01-01

The goal of this paper is to derive a risk map for earthquake occurrences in Pakistan from a catalogue that contains spatial coordinates of shallow earthquakes of magnitude 4.5 or larger aggregated over calendar years. We test relative temporal stationarity and use the inhomogeneous J–function to

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

Identification of radon anomalies related to earthquakes

International Nuclear Information System (INIS)

Ozdas, M.; Inceoglu, F.; Rahman, C.; Yaprak, G.

2009-01-01

Put of many proposed earthquake precursors, temporal radon variation in soil is classified as one of a few promising geochemical signals that may be used for earthquake prediction. However, to use radon variation in soil gas as a reliable earthquake precursor, it must be realized that radon changes are controlled not only by deeper phenomena such as earthquake, but they are also controlled by meteorological parameters such as precipitation, barometric pressure, air temperature and etc. Further studies are required to differentiate the changes in the measured radon concentration caused by tectonic disturbances from the meteorological parameters. In the current study, temporal radon variations in soil gas along active faults in Alasehir of Gediz Graben Systems have been continuously monitored by LR-115 nuclear track detectors for two years. Additionally, the meteorological parameters such as barometric pressure, rainfall and air temperature at the monitoring site have been observed during the same period. Accordingly, regression analysis have been applied to the collected data to identify the radon anomalies due to the seismic activities from those of meteorological conditions.

30 CFR 250.192 - What reports and statistics must I submit relating to a hurricane, earthquake, or other natural...

Science.gov (United States)

2010-07-01

... relating to a hurricane, earthquake, or other natural occurrence? 250.192 Section 250.192 Mineral Resources... statistics must I submit relating to a hurricane, earthquake, or other natural occurrence? (a) You must... tropical storm, or an earthquake. Statistics include facilities and rigs evacuated and the amount of...

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

Comparative risk assessments for the city of Pointe-à-Pitre (French West Indies): earthquakes and storm surge

Science.gov (United States)

Reveillere, A. R.; Bertil, D. B.; Douglas, J. D.; Grisanti, L. G.; Lecacheux, S. L.; Monfort, D. M.; Modaressi, H. M.; Müller, H. M.; Rohmer, J. R.; Sedan, O. S.

2012-04-01

relevant historical cyclones and on the simulation of the associated wave and cyclonic surge. The combined local sea elevations, called "set-up", are then fitted with a statistical distribution in order to obtain its time return characteristics. Several run-ups are then extracted, the inundation areas are calculated and the relative losses of the affected assets are deduced. The Probabilistic Seismic Hazard Assessment and the exposed elements location and seismic vulnerability result from past public risk assessment studies. The loss estimations are computed for several return time periods, measured in percentage of buildings being in a given EMS-98 damage state per grid block, which are then converted into loss ratio. In parallel, an asset estimation is conducted. It is mainly focused on private housing, but it considers some major public infrastructures as well. The final outcome of this work is a direct economic loss-frequency plot for earthquake and storm surge. The Probable Maximum Loss and the Average Annual Loss derivate from this risk curve. In addition, different sources of uncertainty are identified through the loss estimation process. The full propagation of these uncertainties can provide an interval of confidence, which can be assigned to the risk-curve and we show how such additional information can be useful for risk comparison.

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)

Predicted Attenuation Relation and Observed Ground Motion of Gorkha Nepal Earthquake of 25 April 2015

Science.gov (United States)

Singh, R. P.; Ahmad, R.

2015-12-01

A comparison of recent observed ground motion parameters of recent Gorkha Nepal earthquake of 25 April 2015 (Mw 7.8) with the predicted ground motion parameters using exitsing attenuation relation of the Himalayan region will be presented. The recent earthquake took about 8000 lives and destroyed thousands of poor quality of buildings and the earthquake was felt by millions of people living in Nepal, China, India, Bangladesh, and Bhutan. The knowledge of ground parameters are very important in developing seismic code of seismic prone regions like Himalaya for better design of buildings. The ground parameters recorded in recent earthquake event and aftershocks are compared with attenuation relations for the Himalayan region, the predicted ground motion parameters show good correlation with the observed ground parameters. The results will be of great use to Civil engineers in updating existing building codes in the Himlayan and surrounding regions and also for the evaluation of seismic hazards. The results clearly show that the attenuation relation developed for the Himalayan region should be only used, other attenuation relations based on other regions fail to provide good estimate of observed ground motion parameters.

Risk Factors of Post-traumatic Stress and Depressive Disorders in Longmenshan Adolescents After the 2013 Lushan Earthquake.

Science.gov (United States)

Xu, Jiuping; Wang, Yan; Tang, Wanjie

2018-03-06

This study examined the severity of post-traumatic stress and depressive disorders in Longmenshan adolescents after the 2013 Lushan earthquake, as well as relationships among earthquake-related exposure, post-earthquake negative factors, previous exposure to the 2008 Wenchuan earthquake, and level of earthquake impact (city). A cross-sectional survey was conducted among adolescents in Lushan (n = 1416), Baoxing (n = 1102) and Tianquan (n = 1265) at 3 years after the Lushan earthquake. Respondents were evaluated using the Earthquake Experience Scale, the Adolescent Self-rating Life Events Checklist (ASLEC), the Children's Revised Impact of Event Scale (CRIES-13), and the Depression Self-Rating Scale (KADS-6). High levels of post-traumatic stress and depression symptoms were found among adolescents in the most heavily affected cities, and these symptoms were more severe in respondents exposed to the 2008 earthquake. PTSD correlated most strongly with earthquake exposure, whereas depression correlated most strongly with psychosocial stressors following the event.

Scaling relation between earthquake magnitude and the departure time from P wave similar growth

Science.gov (United States)

Noda, Shunta; Ellsworth, William L.

2016-01-01

We introduce a new scaling relation between earthquake magnitude (M) and a characteristic of initial P wave displacement. By examining Japanese K-NET data averaged in bins partitioned by Mw and hypocentral distance, we demonstrate that the P wave displacement briefly displays similar growth at the onset of rupture and that the departure time (Tdp), which is defined as the time of departure from similarity of the absolute displacement after applying a band-pass filter, correlates with the final M in a range of 4.5 ≤ Mw ≤ 7. The scaling relation between Mw and Tdp implies that useful information on the final M can be derived while the event is still in progress because Tdp occurs before the completion of rupture. We conclude that the scaling relation is important not only for earthquake early warning but also for the source physics of earthquakes.

Depressive symptoms and associated psychosocial factors among adolescent survivors 30 months after 2008 Wenchuan earthquake: A follow-up study

Directory of Open Access Journals (Sweden)

Xuliang eShi

2016-03-01

Full Text Available AbstractPurpose: This study longitudinally investigated the changes of depressive symptoms among adolescent survivors over two years and a half after the 2008 Wenchuan earthquake in China, as well as the predictive effects of demographic characteristics, earthquake exposure, negative life events, social support and dispositional resilience on the risk of depressive symptoms at two time points after the earthquake.Methods: Participants were 1573 adolescent survivors (720 males and 853 females, mean age at initial survey =15 ± 1.26, whose depressive symptoms were assessed at 6 months (T6m and 30 months (T30m post-earthquake. Data on demographics, earthquake exposure and dispositional resilience were collected at T6m. Negative life events and social support were measured at T6m and 24 months (T24m post-earthquake.Results: The prevalence rates of probable depression, 27.5% at T6m and 27.2% at T30m, maintained relatively stable over time. Female gender was related with higher risk of depressive symptoms at both T6m and T30m, while being only-child could only predict higher risk of depressive symptoms at T30m. Negative life events and social support at T6m, as well as earthquake exposure, were concurrently associated with increased risk of depressive symptoms at T6m, but not associated with the risk of depressive symptoms at T30m, while negative life events and social support at T24m could predict depressive symptoms at T30m, all of which suggested that these variables may have strong but short-term effect on adolescents’ depressive symptoms post-earthquake. Besides, dispositional resilience was evidenced as a relatively stable negative predictor for depressive symptoms.Conclusions: These findings could inform mental health professionals regarding how to screen adolescent survivors at high risk for depression, so as to provide them with timely and appropriate mental health services based on the identified risk and protective factors for depressive

A Study on Earthquake-Related Geoid Deformation at Beijing-Tangshan and West Yunnan During 1985-1998

Science.gov (United States)

Li, Z.

2006-05-01

Based on the determination of the non-tidal variations in the deflection of the vertical (or PlumbLine Variations, PLVs) at Beijing astronomical observatory, the work has been extended into a determination of the PLV array within a 4 x 1 (degree) area at Beijing-Tangshan. By repeated observations of the gravimetric network, 46 batches of this PLV array, and consequently the relative geoid deformation (RGD), of the area during 1987- 1998 have been determined. Together with the 23 earthquakes (Mb > 4.0) in the area during the same period, a comparison is done between an earthquake event and the related RGD. Similar study has also been carried out for the case in West Yunnan, where 32 batches of repeated gravimetric observations of the network there during 1985-1998 have been performed from which the 32 PLV array, as well as the corresponding RGD, of a 2 x 2 (dergee) area has been calculated. A comparison is also done at West Yunnan between an earthquake event and its related RGD. It is interesting to see that the earthquake and the RGD measured are related. It appears that there is usually a detectable RGD nearby well before an earthquake, but a contrary RGD afterwards. The study provides us a new approach in geodesy on the RGD determination, as well as a new measurable phenomenon in an earthquake event at Beijing-Tangshan and West Yunnan. The study also provides us evidence in which the existence of the PLVs, as well as the corresponding RGD, at Beijing- Tangshan and West Yunnan becomes more conclusive. Their potential usage in geodesy and seismology, as well as in other related sciences, is now expected.

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

Science.gov (United States)

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

2014-05-01

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

How to provide risk information. Based on citizen's evaluation of messages concerning radiation protection and anti-earthquake measures of nuclear power plant

International Nuclear Information System (INIS)

Tsuchiya, Tomoko; Kosugi, Motoko; Nakamura, Yasushi; Takahashi, Shigeaki; Harayama, Satoko

2009-01-01

The Framework for Nuclear Energy Policy in Japan, decided in 2005, requests implementation of risk communication to regain social trust on nuclear industry. Electric power companies, however, have few experiences of providing risk information as the first step of risk communication. This report analyzes which message is understandable, useful and trustworthy, by comparing two sets of different messages concerning radiation protection and anti-earthquake measures of nuclear power plant, respectively, based on interview survey for 30 people live in Tokyo metropolitan area. Participants in our survey evaluate the message about radiation protection including risk information is more reliable than one without risk information, but the former is less understandable and more anxious than the latter. In the case of messages regarding seismic measures of nuclear power plant, people are not satisfied with the argument which anti-earthquake measures are implemented, but want to know adequate grounds on which to admit that those measures are thorough. Another message of seismic measures we drafted contains basic knowledge about scales of earthquake, and shows that nuclear industry will consider bigger earthquake than ones in the past records, learn from past experience and improve their measures. 70% of participants assess this message more understandable, useful and trustworthy than the other to explain only seismic measures implemented. (author)

Earthquakes, May-June 1991

Science.gov (United States)

Person, W.J.

1992-01-01

One major earthquake occurred during this reporting period. This was a magntidue 7.1 in Indonesia (Minahassa Peninsula) on June 20. Earthquake-related deaths were reported in the Western Caucasus (Georgia, USSR) on May 3 and June 15. One earthquake-related death was also reported El Salvador on June 21. 

Applications of research from the U.S. Geological Survey program, assessment of regional earthquake hazards and risk along the Wasatch Front, Utah

Science.gov (United States)

Gori, Paula L.

1993-01-01

engineering studies. Translated earthquake hazard maps have also been developed to identify areas that are particularly vulnerable to various causes of damage such as ground shaking, surface rupturing, and liquefaction. The implementation of earthquake hazard reduction plans are now under way in various communities in Utah. The results of a survey presented in this paper indicate that technical public officials (planners and building officials) have an understanding of the earthquake hazards and how to mitigate the risks. Although the survey shows that the general public has a slightly lower concern about the potential for economic losses, they recognize the potential problems and can support a number of earthquake mitigation measures. The study suggests that many community groups along the Wasatch Front, including volunteer groups, business groups, and elected and appointed officials, are ready for action-oriented educational programs. These programs could lead to a significant reduction in the risks associated with earthquake hazards. A DATA BASE DESIGNED FOR URBAN SEISMIC HAZARDS STUDIES: A computerized data base has been designed for use in urban seismic hazards studies conducted by the U.S. Geological Survey. The design includes file structures for 16 linked data sets, which contain geological, geophysical, and seismological data used in preparing relative ground response maps of large urban areas. The data base is organized along relational data base principles. A prototype urban hazards data base has been created for evaluation in two urban areas currently under investigation: the Wasatch Front region of Utah and the Puget Sound area of Washington. The initial implementation of the urban hazards data base was accomplished on a microcomputer using dBASE III Plus software and transferred to minicomputers and a work station. A MAPPING OF GROUND-SHAKING INTENSITIES FOR SALT LAKE COUNTY, UTAH: This paper documents the development of maps showing a

Defeating Earthquakes

Science.gov (United States)

Stein, R. S.

2012-12-01

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

Health behaviors of victims and related factors in Wenchuan earthquake resettlement sites.

Science.gov (United States)

Liu, Qiaolan; Zhou, Hongyu; Zhou, Huan; Yang, Yang; Yang, Xiaoyan; Yu, Lingyun; Qiu, Peiyuan; Ma, Xiao

2011-03-01

The purpose of this study was to describe the health behaviors of earthquake victims related to gastrointestinal and respiratory infectious diseases in the centralized transitional earthquake resettlement sites in Wenchuan, China; and to identify key factors related to health behaviors that may inform local infectious diseases prevention and control strategies. Data were collected using a questionnaire that included questions about socio-demographic characteristics and health beliefs and behaviors. In total, 1411 participants were included through a two-stage random sampling strategy. A bivariate multilevel model was used to explore the related factors. Approximately 67% of the participants wash their hands after going to lavatories every time, and 87% felt uncomfortable spitting on the ground. The more the participants perceived their susceptibility to and the severity of infectious diseases, the better their health-related behaviors (P resettlement sites (P resettlement sites. Copyright © 2011 Elsevier Inc. All rights reserved.

Radon variations in the Wellington region, New Zealand, and their relation to earthquakes

International Nuclear Information System (INIS)

Robinson, R.; Whitehead, N.E.

1992-01-01

Temporal changes in the radon content of ground water and soil gas have been monitored in the Wellington region since early 1978 in order to examine their relation to earthquakes. New Zealand is a region of plate convergence and subduction with a moderate level of seismicity, both crustal and deep. The measurement technique is of the 'Track Edge' type and is simple and inexpensive to implement but is subject to several sources of error. The major feature of the data, in the form of monthly mean radon levels, is a large long term rise and fall in level lasting 2 1/2 to 3 years. Data from five sites are well correlated due to this feature but shorter term fluctuations are less well correlated. Effects of changes in the weather are small. The long term radon 'anomaly' cannot be convincingly related to any particular earthquake. Nor do earthquakes up to magnitude 5.2 within 100km show any clear effect on the radon level. Despite the lack of clear precursory effects due to specific earthquakes, there are some weak correlations between the radon level and the seismicity as a whole. These correlations, if physically real imply that post-event effects on radon are at least as important as precursory effects. However, it is not certain that the radon level is directly affected by earthquakes at all. It seems likely that the radon level reflects changes in regional strain rate that also monitor the seismicity. (auth). 14 refs., 6 figs., 4 tabs

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.

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

Science.gov (United States)

Wang, Yan; Lu, Yi

2018-01-01

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

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.

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.

Earthquake damage to underground facilities

International Nuclear Information System (INIS)

Pratt, H.R.; Hustrulid, W.A.; Stephenson, D.E.

1978-11-01

The potential seismic risk for an underground nuclear waste repository will be one of the considerations in evaluating its ultimate location. However, the risk to subsurface facilities cannot be judged by applying intensity ratings derived from the surface effects of an earthquake. A literature review and analysis were performed to document the damage and non-damage due to earthquakes to underground facilities. Damage from earthquakes to tunnels, s, and wells and damage (rock bursts) from mining operations were investigated. Damage from documented nuclear events was also included in the study where applicable. There are very few data on damage in the subsurface due to earthquakes. This fact itself attests to the lessened effect of earthquakes in the subsurface because mines exist in areas where strong earthquakes have done extensive surface damage. More damage is reported in shallow tunnels near the surface than in deep mines. In mines and tunnels, large displacements occur primarily along pre-existing faults and fractures or at the surface entrance to these facilities.Data indicate vertical structures such as wells and shafts are less susceptible to damage than surface facilities. More analysis is required before seismic criteria can be formulated for the siting of a nuclear waste repository

Psychological Vulnerability and Earthquake Risk Perception in Bucharest/Romania

Science.gov (United States)

Romeo Cretu, Zeno; Armas, Iuliana; Stanciugelu, Irina

2010-05-01

The importance of studying the relationship with the natural hazard events from a psycho-social perspective is fundamental by the experience with past disasters as much as by the research in the field that proved that the people's psychologic structures may constitute a starting point for risk reduction. People's psycho-behavioural patterns contain conscious or unconscious references to the environmental risk, thus creating certain adjustment strategies and mechanisms, with a certain degree of psychological vulnerability. In modern man's case, the high level of awareness in front of natural dangers, doubled by the perception of the environment's unsafety, experienced as a lack of control, brings to attention nowadays the problematic of the analysis of natural risk perception, as a main factor in the adjustment of human communities' capacity of adapting to the natural environment's dynamics. The major objective of this present work is, based on the development of an efficient evaluation methodology, to identify specific relational patterns to seismic risk in Bucharest, function the characteristics of the urban environment, the social, economical and psychological vulnerability, with results that can be applied for disaster management. For explaining human reactions and the way in which they perceive and evaluate the psychological resources, on a daily basis, but also in risk situations (earthquakes), a multi-modal questionnaire was conceived through qualitative methods (a focus group, along with experts from the Public and Administrative Sciences National School, Risk Communication Center). The questionnaire was structured on a 49 items sequence, in which were included different type of questions (with single or multiple answers, open questions etc), and also questions using different scaling methods. The items caught cognitive elements (expectations, anticipations and negative or positive judgments regarding risk element), affective (feelings) and behavioral

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

Directory of Open Access Journals (Sweden)

Y. Altinok

2005-01-01

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

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

Science.gov (United States)

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

2015-10-01

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

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

Science.gov (United States)

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

1990-01-01

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

Aseismic blocks and destructive earthquakes in the Aegean

Science.gov (United States)

Stiros, Stathis

2017-04-01

Aseismic areas are not identified only in vast, geologically stable regions, but also within regions of active, intense, distributed deformation such as the Aegean. In the latter, "aseismic blocks" about 200m wide were recognized in the 1990's on the basis of the absence of instrumentally-derived earthquake foci, in contrast to surrounding areas. This pattern was supported by the available historical seismicity data, as well as by geologic evidence. Interestingly, GPS evidence indicates that such blocks are among the areas characterized by small deformation rates relatively to surrounding areas of higher deformation. Still, the largest and most destructive earthquake of the 1990's, the 1995 M6.6 earthquake occurred at the center of one of these "aseismic" zones at the northern part of Greece, found unprotected against seismic hazard. This case was indeed a repeat of the case of the tsunami-associated 1956 Amorgos Island M7.4 earthquake, the largest 20th century event in the Aegean back-arc region: the 1956 earthquake occurred at the center of a geologically distinct region (Cyclades Massif in Central Aegean), till then assumed aseismic. Interestingly, after 1956, the overall idea of aseismic regions remained valid, though a "promontory" of earthquake prone-areas intruding into the aseismic central Aegean was assumed. Exploitation of the archaeological excavation evidence and careful, combined analysis of historical and archaeological data and other palaeoseismic, mostly coastal data, indicated that destructive and major earthquakes have left their traces in previously assumed aseismic blocks. In the latter earthquakes typically occur with relatively low recurrence intervals, >200-300 years, much smaller than in adjacent active areas. Interestingly, areas assumed a-seismic in antiquity are among the most active in the last centuries, while areas hit by major earthquakes in the past are usually classified as areas of low seismic risk in official maps. Some reasons

Characteristics of Gyeongju earthquake, moment magnitude 5.5 and relative relocations of aftershocks

Science.gov (United States)

Cho, ChangSoo; Son, Minkyung

2017-04-01

There is low seismicity in the korea peninsula. According historical record in the historic book, There were several strong earthquake in the korea peninsula. Especially in Gyeongju of capital city of the Silla dynasty, few strong earthquakes caused the fatalities of several hundreds people 1,300 years ago and damaged the houses and make the wall of castles collapsed. Moderate strong earthquake of moment magnitude 5.5 hit the city in September 12, 2016. Over 1000 aftershocks were detected. The numbers of occurrences of aftershock over time follows omori's law well. The distribution of relative locations of 561 events using clustering aftershocks by cross-correlation between P and S waveform of the events showed the strike NNE 25 30 o and dip 68 74o of fault plane to cause the earthquake matched with the fault plane solution of moment tensor inversion well. The depth of range of the events is from 11km to 16km. The width of distribution of event locations is about 5km length. The direction of maximum horizontal stress by inversion of stress for the moment solutions of main event and large aftershocks is similar to the known maximum horizontal stress direction of the korea peninsula. The relation curves between moment magnitude and local magnitude of aftershocks shows that the moment magnitude increases slightly more for events of size less than 2.0

Post-traumatic stress disorder status in a rescue group after the Wenchuan earthquake relief.

Science.gov (United States)

Huang, Junhua; Liu, Qunying; Li, Jinliang; Li, Xuejiang; You, Jin; Zhang, Liang; Tian, Changfu; Luan, Rongsheng

2013-07-15

Previous studies have suggested that the incidence of post-traumatic stress disorder in earthquake rescue workers is relatively high. Risk factors for this disorder include demographic characteristics, earthquake-related high-risk factors, risk factors in the rescue process, personality, social support and coping style. This study examined the current status of a unit of 1 040 rescue workers who participated in earthquake relief for the Wenchuan earthquake that occurred on May 12(th), 2008. Post-traumatic stress disorder was diagnosed primarily using the Clinician-Administered Post-traumatic Stress Disorder Scale during structured interviews. Univariate and multivariate statistical analyses were used to examine major risk factors that contributed to the incidence of post-traumatic stress disorder. Results revealed that the incidence of this disorder in the rescue group was 5.96%. The impact factors in univariate analysis included death of family members, contact with corpses or witnessing of the deceased or seriously injured, near-death experience, severe injury or mental trauma in the rescue process and working at the epicenter of the earthquake. Correlation analysis suggested that post-traumatic stress disorder was positively correlated with psychotic and neurotic personalities, negative coping and low social support. Impact factors in multivariate logistic regression analysis included near-death experience, severe injury or mental trauma, working in the epicenter of the rescue, neurotic personality, negative coping and low social support, among which low social support had the largest odds ratio of 20.42. Findings showed that the occurrence of post-traumatic stress disorder was the result of the interaction of multiple factors.

Post-traumatic stress disorder status in a rescue group after the Wenchuan earthquake relief

Science.gov (United States)

Huang, Junhua; Liu, Qunying; Li, Jinliang; Li, Xuejiang; You, Jin; Zhang, Liang; Tian, Changfu; Luan, Rongsheng

2013-01-01

Previous studies have suggested that the incidence of post-traumatic stress disorder in earthquake rescue workers is relatively high. Risk factors for this disorder include demographic characteristics, earthquake-related high-risk factors, risk factors in the rescue process, personality, social support and coping style. This study examined the current status of a unit of 1 040 rescue workers who participated in earthquake relief for the Wenchuan earthquake that occurred on May 12th, 2008. Post-traumatic stress disorder was diagnosed primarily using the Clinician-Administered Post-traumatic Stress Disorder Scale during structured interviews. Univariate and multivariate statistical analyses were used to examine major risk factors that contributed to the incidence of post-traumatic stress disorder. Results revealed that the incidence of this disorder in the rescue group was 5.96%. The impact factors in univariate analysis included death of family members, contact with corpses or witnessing of the deceased or seriously injured, near-death experience, severe injury or mental trauma in the rescue process and working at the epicenter of the earthquake. Correlation analysis suggested that post-traumatic stress disorder was positively correlated with psychotic and neurotic personalities, negative coping and low social support. Impact factors in multivariate logistic regression analysis included near-death experience, severe injury or mental trauma, working in the epicenter of the rescue, neurotic personality, negative coping and low social support, among which low social support had the largest odds ratio of 20.42. Findings showed that the occurrence of post-traumatic stress disorder was the result of the interaction of multiple factors. PMID:25206499

From Colfiorito to L'Aquila Earthquake: learning from the past to communicating the risk of the present

Science.gov (United States)

Lanza, T.; Crescimbene, M.; La Longa, F.

2012-04-01

Italy is a country at risk of impending earthquake in the near future. Very probably, as it has already happened in the 13 years between the last two important seismic events (Colfiorito 1997- L'Aquila 2009), there won't be enough time to solve all the problems connected to seismic risk: first of all the corruption related to politics concerning buildings; the lack of the money necessary to strengthen the already existing ones, historical centres, monuments and the masterpieces of Art; the difficult relations of the Institutions with the traditional media (newspapers, radio and TV) and, at the same time, the new media (web); the difficulties for scientists to reach important results in the immediate future due to the lack of funding and, last but not least, to the conflicting relationships inside the scientific community itself. In this scenario, communication and education play a crucial role in minimizing the risk of the population. In the present work we reconsider the past with the intent of starting to trace a path for a future strategy of risk communication where everybody involved, included the population, should do his best in order to face the next emergency.

Are seismic hazard assessment errors and earthquake surprises unavoidable?

Science.gov (United States)

Kossobokov, Vladimir

2013-04-01

Why earthquake occurrences bring us so many surprises? The answer seems evident if we review the relationships that are commonly used to assess seismic hazard. The time-span of physically reliable Seismic History is yet a small portion of a rupture recurrence cycle at an earthquake-prone site, which makes premature any kind of reliable probabilistic statements about narrowly localized seismic hazard. Moreover, seismic evidences accumulated to-date demonstrate clearly that most of the empirical relations commonly accepted in the early history of instrumental seismology can be proved erroneous when testing statistical significance is applied. Seismic events, including mega-earthquakes, cluster displaying behaviors that are far from independent or periodic. Their distribution in space is possibly fractal, definitely, far from uniform even in a single segment of a fault zone. Such a situation contradicts generally accepted assumptions used for analytically tractable or computer simulations and complicates design of reliable methodologies for realistic earthquake hazard assessment, as well as search and definition of precursory behaviors to be used for forecast/prediction purposes. As a result, the conclusions drawn from such simulations and analyses can MISLEAD TO SCIENTIFICALLY GROUNDLESS APPLICATION, which is unwise and extremely dangerous in assessing expected societal risks and losses. For example, a systematic comparison of the GSHAP peak ground acceleration estimates with those related to actual strong earthquakes, unfortunately, discloses gross inadequacy of this "probabilistic" product, which appears UNACCEPTABLE FOR ANY KIND OF RESPONSIBLE SEISMIC RISK EVALUATION AND KNOWLEDGEABLE DISASTER PREVENTION. The self-evident shortcomings and failures of GSHAP appeals to all earthquake scientists and engineers for an urgent revision of the global seismic hazard maps from the first principles including background methodologies involved, such that there becomes: (a) a

Natural Time, Nowcasting and the Physics of Earthquakes: Estimation of Seismic Risk to Global Megacities

Science.gov (United States)

Rundle, John B.; Luginbuhl, Molly; Giguere, Alexis; Turcotte, Donald L.

2018-02-01

Natural Time ("NT") refers to the concept of using small earthquake counts, for example of M > 3 events, to mark the intervals between large earthquakes, for example M > 6 events. The term was first used by Varotsos et al. (2005) and later by Holliday et al. (2006) in their studies of earthquakes. In this paper, we discuss ideas and applications arising from the use of NT to understand earthquake dynamics, in particular by use of the idea of nowcasting. Nowcasting differs from forecasting, in that the goal of nowcasting is to estimate the current state of the system, rather than the probability of a future event. Rather than focus on an individual earthquake faults, we focus on a defined local geographic region surrounding a particular location. This local region is considered to be embedded in a larger regional setting from which we accumulate the relevant statistics. We apply the nowcasting idea to the practical development of methods to estimate the current state of risk for dozens of the world's seismically exposed megacities, defined as cities having populations of over 1 million persons. We compute a ranking of these cities based on their current nowcast value, and discuss the advantages and limitations of this approach. We note explicitly that the nowcast method is not a model, in that there are no free parameters to be fit to data. Rather, the method is simply a presentation of statistical data, which the user can interpret. Among other results, we find, for example, that the current nowcast ranking of the Los Angeles region is comparable to its ranking just prior to the January 17, 1994 Northridge earthquake.

Semi-automated landform classification for hazard mapping of soil liquefaction by earthquake

Science.gov (United States)

Nakano, Takayuki

2018-05-01

Soil liquefaction damages were caused by huge earthquake in Japan, and the similar damages are concerned in near future huge earthquake. On the other hand, a preparation of soil liquefaction risk map (soil liquefaction hazard map) is impeded by the difficulty of evaluation of soil liquefaction risk. Generally, relative soil liquefaction risk should be able to be evaluated from landform classification data by using experimental rule based on the relationship between extent of soil liquefaction damage and landform classification items associated with past earthquake. Therefore, I rearranged the relationship between landform classification items and soil liquefaction risk intelligibly in order to enable the evaluation of soil liquefaction risk based on landform classification data appropriately and efficiently. And I developed a new method of generating landform classification data of 50-m grid size from existing landform classification data of 250-m grid size by using digital elevation model (DEM) data and multi-band satellite image data in order to evaluate soil liquefaction risk in detail spatially. It is expected that the products of this study contribute to efficient producing of soil liquefaction hazard map by local government.

Overview of the relations earthquake source parameters and the specification of strong ground motion for design purposes

International Nuclear Information System (INIS)

Bernreuter, D.L.

1977-08-01

One of the most important steps in the seismic design process is the specification of the appropriate ground motion to be input into the design analysis. From the point-of-view of engineering design analysis, the important parameters are peak ground acceleration, spectral shape and peak spectral levels. In a few cases, ground displacement is a useful parameter. The earthquake is usually specified by giving its magnitude and either the epicentral distance or the distance of the closest point on the causitive fault to the site. Typically, the appropriate ground motion parameters are obtained using the specified magnitude and distance in equations obtained from regression analysis among the appropriate variables. Two major difficulties with such an approach are: magnitude is not the best parameter to use to define the strength of an earthquake, and little near-field data is available to establish the appropriate form for the attenuation of the ground motion with distance, source size and strength. These difficulties are important for designing a critical facility; i.e., one for which a very low risk of exceeding the design ground motion is required. Examples of such structures are nuclear power plants, schools and hospitals. for such facilities, a better understanding of the relation between the ground motion and the important earthquake source parameters could be very useful for several reasons

Association between earthquake events and cholera outbreaks: a cross-country 15-year longitudinal analysis.

Science.gov (United States)

Sumner, Steven A; Turner, Elizabeth L; Thielman, Nathan M

2013-12-01

Large earthquakes can cause population displacement, critical sanitation infrastructure damage, and increased threats to water resources, potentially predisposing populations to waterborne disease epidemics such as cholera. Problem The risk of cholera outbreaks after earthquake disasters remains uncertain. A cross-country analysis of World Health Organization (WHO) cholera data that would contribute to this discussion has yet to be published. A cross-country longitudinal analysis was conducted among 63 low- and middle-income countries from 1995-2009. The association between earthquake disasters of various effect sizes and a relative spike in cholera rates for a given country was assessed utilizing fixed-effects logistic regression and adjusting for gross domestic product per capita, water and sanitation level, flooding events, percent urbanization, and under-five child mortality. Also, the association between large earthquakes and cholera rate increases of various degrees was assessed. Forty-eight of the 63 countries had at least one year with reported cholera infections during the 15-year study period. Thirty-six of these 48 countries had at least one earthquake disaster. In adjusted analyses, country-years with ≥10,000 persons affected by an earthquake had 2.26 times increased odds (95 CI, 0.89-5.72, P = .08) of having a greater than average cholera rate that year compared to country-years having earthquake. The association between large earthquake disasters and cholera infections appeared to weaken as higher levels of cholera rate increases were tested. A trend of increased risk of greater than average cholera rates when more people were affected by an earthquake in a country-year was noted. However these findings did not reach statistical significance at traditional levels and may be due to chance. Frequent large-scale cholera outbreaks after earthquake disasters appeared to be relatively uncommon.

[The hazards of reconstruction: anthropology of dwelling and social health risk in the L'Aquila (Central Italy) post-earthquake].

Science.gov (United States)

Ciccozzi, Antonello

2016-01-01

Even starting from the purpose of restoring the damage caused by a natural disaster, the post-earthquake reconstructions imply the risk of triggering a set of social disasters that may affect the public health sphere. In the case of the L'Aquila earthquake this risk seems to emerge within the urban planning on two levels of dwelling: at a landscape level, where there has been a change in the shape of the city towards a sprawling-sprinkling process; at an architectural level, on the problematic relationship between the politics and the poetics of cultural heritage protection and the goal to get restoration works capable to ensure the citizens seismic safety.

Salient Features of the 2015 Gorkha, Nepal Earthquake in Relation to Earthquake Cycle and Dynamic Rupture Models

Science.gov (United States)

Ampuero, J. P.; Meng, L.; Hough, S. E.; Martin, S. S.; Asimaki, D.

2015-12-01

Two salient features of the 2015 Gorkha, Nepal, earthquake provide new opportunities to evaluate models of earthquake cycle and dynamic rupture. The Gorkha earthquake broke only partially across the seismogenic depth of the Main Himalayan Thrust: its slip was confined in a narrow depth range near the bottom of the locked zone. As indicated by the belt of background seismicity and decades of geodetic monitoring, this is an area of stress concentration induced by deep fault creep. Previous conceptual models attribute such intermediate-size events to rheological segmentation along-dip, including a fault segment with intermediate rheology in between the stable and unstable slip segments. We will present results from earthquake cycle models that, in contrast, highlight the role of stress loading concentration, rather than frictional segmentation. These models produce "super-cycles" comprising recurrent characteristic events interspersed by deep, smaller non-characteristic events of overall increasing magnitude. Because the non-characteristic events are an intrinsic component of the earthquake super-cycle, the notion of Coulomb triggering or time-advance of the "big one" is ill-defined. The high-frequency (HF) ground motions produced in Kathmandu by the Gorkha earthquake were weaker than expected for such a magnitude and such close distance to the rupture, as attested by strong motion recordings and by macroseismic data. Static slip reached close to Kathmandu but had a long rise time, consistent with control by the along-dip extent of the rupture. Moreover, the HF (1 Hz) radiation sources, imaged by teleseismic back-projection of multiple dense arrays calibrated by aftershock data, was deep and far from Kathmandu. We argue that HF rupture imaging provided a better predictor of shaking intensity than finite source inversion. The deep location of HF radiation can be attributed to rupture over heterogeneous initial stresses left by the background seismic activity

Lessons from the conviction of the L'Aquila seven: The standard probabilistic earthquake hazard and risk assessment is ineffective

Science.gov (United States)

Wyss, Max

2013-04-01

An earthquake of M6.3 killed 309 people in L'Aquila, Italy, on 6 April 2011. Subsequently, a judge in L'Aquila convicted seven who had participated in an emergency meeting on March 30, assessing the probability of a major event to follow the ongoing earthquake swarm. The sentence was six years in prison, a combine fine of 2 million Euros, loss of job, loss of retirement rent, and lawyer's costs. The judge followed the prosecution's accusation that the review by the Commission of Great Risks had conveyed a false sense of security to the population, which consequently did not take their usual precautionary measures before the deadly earthquake. He did not consider the facts that (1) one of the convicted was not a member of the commission and had merrily obeyed orders to bring the latest seismological facts to the discussion, (2) another was an engineer who was not required to have any expertise regarding the probability of earthquakes, (3) and two others were seismologists not invited to speak to the public at a TV interview and a press conference. This exaggerated judgment was the consequence of an uproar in the population, who felt misinformed and even mislead. Faced with a population worried by an earthquake swarm, the head of the Italian Civil Defense is on record ordering that the population be calmed, and the vice head executed this order in a TV interview one hour before the meeting of the Commission by stating "the scientific community continues to tell me that the situation is favorable and that there is a discharge of energy." The first lesson to be learned is that communications to the public about earthquake hazard and risk must not be left in the hands of someone who has gross misunderstandings about seismology. They must be carefully prepared by experts. The more significant lesson is that the approach to calm the population and the standard probabilistic hazard and risk assessment, as practiced by GSHAP, are misleading. The later has been criticized as

What is the best use of 100 Euros to reduce the earthquake risk of a residential masonry building in a developed nation? Optimisation and Quantification of the benefits of risk reduction

Science.gov (United States)

Daniell, James; Schaefer, Andreas; Wenzel, Friedemann

2015-04-01

The average loss per building in developed countries like Australia or Switzerland due to earthquakes will be far in excess of 100€ over a political lifetime of 4 years (via a stochastic risk assessment). So a good question is, what can be done for 100€ and a bit of hard work, to strengthen and retrofit a URM (unreinforced masonry house). Of course much of the loss occurs in a few large events, but significant damage also occurs from more frequent smaller events. Using the CATDAT Damaging Earthquakes Database (Daniell et al., 2011), 57% of deaths from earthquakes have occurred in masonry buildings since 1900 globally. Thus, with a view towards life safety and the maximum return on investment, different options are tested and discussed for retrofitting the average brick house for earthquake resistance. Bolting and bracketing furniture, electrical equipment and valuables to walls, the removal or tying in of certain non-structural elements, as well as adjustments such as seismic wallpaper and reinforcement are tested from empirical and analytical experience from around the world. Of course, earthquakes are not the only main concern for developed nation populations, so a view as to the best use of the 100€ is looked at in combination with other disaster types. Insurance takeout and its implications are also discussed. The process is repeated for the D-A-CH (Germany, Austria and Switzerland) region in order to see the regional economic implications for widespread awareness of earthquake risks and losses. The risk reduction is quantified and is seen to be significant for nearly all of the D-A-CH region. This analysis has implications for developed and developing nations alike.

Fragility analysis of flood protection structures in earthquake and flood prone areas around Cologne, Germany for multi-hazard risk assessment

Science.gov (United States)

Tyagunov, Sergey; Vorogushyn, Sergiy; Munoz Jimenez, Cristina; Parolai, Stefano; Fleming, Kevin; Merz, Bruno; Zschau, Jochen

2013-04-01

The work presents a methodology for fragility analyses of fluvial earthen dikes in earthquake and flood prone areas. Fragility estimates are being integrated into the multi-hazard (earthquake-flood) risk analysis being undertaken within the framework of the EU FP7 project MATRIX (New Multi-Hazard and Multi-Risk Assessment Methods for Europe) for the city of Cologne, Germany. Scenarios of probable cascading events due to the earthquake-triggered failure of flood protection dikes and the subsequent inundation of surroundings are analyzed for the area between the gauges Andernach and Düsseldorf along the Rhine River. Along this river stretch, urban areas are partly protected by earthen dikes, which may be prone to failure during exceptional floods and/or earthquakes. The seismic fragility of the dikes is considered in terms of liquefaction potential (factor of safety), estimated by the use of the simplified procedure of Seed and Idriss. It is assumed that initiation of liquefaction at any point throughout the earthen dikes' body corresponds to the failure of the dike and, therefore, this should be taken into account for the flood risk calculations. The estimated damage potential of such structures is presented as a two-dimensional surface (as a function of seismic hazard and water level). Uncertainties in geometrical and geotechnical dike parameters are considered within the framework of Monte Carlo simulations. Taking into consideration the spatial configuration of the existing flood protection system within the area under consideration, seismic hazard curves (in terms of PGA) are calculated for sites along the river segment of interest at intervals of 1 km. The obtained estimates are used to calculate the flood risk when considering the temporal coincidence of seismic and flood events. Changes in flood risk for the considered hazard cascade scenarios are quantified and compared to the single-hazard scenarios.

Earthquake prediction rumors can help in building earthquake awareness: the case of May the 11th 2011 in Rome (Italy)

Science.gov (United States)

Amato, A.; Arcoraci, L.; Casarotti, E.; Cultrera, G.; Di Stefano, R.; Margheriti, L.; Nostro, C.; Selvaggi, G.; May-11 Team

2012-04-01

Banner headlines in an Italian newspaper read on May 11, 2011: "Absence boom in offices: the urban legend in Rome become psychosis". This was the effect of a large-magnitude earthquake prediction in Rome for May 11, 2011. This prediction was never officially released, but it grew up in Internet and was amplified by media. It was erroneously ascribed to Raffaele Bendandi, an Italian self-taught natural scientist who studied planetary motions and related them to earthquakes. Indeed, around May 11, 2011, there was a planetary alignment and this increased the earthquake prediction credibility. Given the echo of this earthquake prediction, INGV decided to organize on May 11 (the same day the earthquake was predicted to happen) an Open Day in its headquarter in Rome to inform on the Italian seismicity and the earthquake physics. The Open Day was preceded by a press conference two days before, attended by about 40 journalists from newspapers, local and national TV's, press agencies and web news magazines. Hundreds of articles appeared in the following two days, advertising the 11 May Open Day. On May 11 the INGV headquarter was peacefully invaded by over 3,000 visitors from 9am to 9pm: families, students, civil protection groups and many journalists. The program included conferences on a wide variety of subjects (from social impact of rumors to seismic risk reduction) and distribution of books and brochures, in addition to several activities: meetings with INGV researchers to discuss scientific issues, visits to the seismic monitoring room (open 24h/7 all year), guided tours through interactive exhibitions on earthquakes and Earth's deep structure. During the same day, thirteen new videos have also been posted on our youtube/INGVterremoti channel to explain the earthquake process and hazard, and to provide real time periodic updates on seismicity in Italy. On May 11 no large earthquake happened in Italy. The initiative, built up in few weeks, had a very large feedback

Analysis of pre-earthquake ionospheric anomalies before the global M = 7.0+ earthquakes in 2010

Directory of Open Access Journals (Sweden)

W. F. Peng

2012-03-01

Full Text Available The pre-earthquake ionospheric anomalies that occurred before the global M = 7.0+ earthquakes in 2010 are investigated using the total electron content (TEC from the global ionosphere map (GIM. We analyze the possible causes of the ionospheric anomalies based on the space environment and magnetic field status. Results show that some anomalies are related to the earthquakes. By analyzing the time of occurrence, duration, and spatial distribution of these ionospheric anomalies, a number of new conclusions are drawn, as follows: earthquake-related ionospheric anomalies are not bound to appear; both positive and negative anomalies are likely to occur; and the earthquake-related ionospheric anomalies discussed in the current study occurred 0–2 days before the associated earthquakes and in the afternoon to sunset (i.e. between 12:00 and 20:00 local time. Pre-earthquake ionospheric anomalies occur mainly in areas near the epicenter. However, the maximum affected area in the ionosphere does not coincide with the vertical projection of the epicenter of the subsequent earthquake. The directions deviating from the epicenters do not follow a fixed rule. The corresponding ionospheric effects can also be observed in the magnetically conjugated region. However, the probability of the anomalies appearance and extent of the anomalies in the magnetically conjugated region are smaller than the anomalies near the epicenter. Deep-focus earthquakes may also exhibit very significant pre-earthquake ionospheric anomalies.

Earthquake hazard evaluation for Switzerland

International Nuclear Information System (INIS)

Ruettener, E.

1995-01-01

Earthquake hazard analysis is of considerable importance for Switzerland, a country with moderate seismic activity but high economic values at risk. The evaluation of earthquake hazard, i.e. the determination of return periods versus ground motion parameters, requires a description of earthquake occurrences in space and time. In this study the seismic hazard for major cities in Switzerland is determined. The seismic hazard analysis is based on historic earthquake records as well as instrumental data. The historic earthquake data show considerable uncertainties concerning epicenter location and epicentral intensity. A specific concept is required, therefore, which permits the description of the uncertainties of each individual earthquake. This is achieved by probability distributions for earthquake size and location. Historical considerations, which indicate changes in public earthquake awareness at various times (mainly due to large historical earthquakes), as well as statistical tests have been used to identify time periods of complete earthquake reporting as a function of intensity. As a result, the catalog is judged to be complete since 1878 for all earthquakes with epicentral intensities greater than IV, since 1750 for intensities greater than VI, since 1600 for intensities greater than VIII, and since 1300 for intensities greater than IX. Instrumental data provide accurate information about the depth distribution of earthquakes in Switzerland. In the Alps, focal depths are restricted to the uppermost 15 km of the crust, whereas below the northern Alpine foreland earthquakes are distributed throughout the entire crust (30 km). This depth distribution is considered in the final hazard analysis by probability distributions. (author) figs., tabs., refs

GEM - The Global Earthquake Model

Science.gov (United States)

Smolka, A.

2009-04-01

Over 500,000 people died in the last decade due to earthquakes and tsunamis, mostly in the developing world, where the risk is increasing due to rapid population growth. In many seismic regions, no hazard and risk models exist, and even where models do exist, they are intelligible only by experts, or available only for commercial purposes. The Global Earthquake Model (GEM) answers the need for an openly accessible risk management tool. GEM is an internationally sanctioned public private partnership initiated by the Organisation for Economic Cooperation and Development (OECD) which will establish an authoritative standard for calculating and communicating earthquake hazard and risk, and will be designed to serve as the critical instrument to support decisions and actions that reduce earthquake losses worldwide. GEM will integrate developments on the forefront of scientific and engineering knowledge of earthquakes, at global, regional and local scale. The work is organized in three modules: hazard, risk, and socio-economic impact. The hazard module calculates probabilities of earthquake occurrence and resulting shaking at any given location. The risk module calculates fatalities, injuries, and damage based on expected shaking, building vulnerability, and the distribution of population and of exposed values and facilities. The socio-economic impact module delivers tools for making educated decisions to mitigate and manage risk. GEM will be a versatile online tool, with open source code and a map-based graphical interface. The underlying data will be open wherever possible, and its modular input and output will be adapted to multiple user groups: scientists and engineers, risk managers and decision makers in the public and private sectors, and the public-at- large. GEM will be the first global model for seismic risk assessment at a national and regional scale, and aims to achieve broad scientific participation and independence. Its development will occur in a

Empirical ground-motion relations for subduction-zone earthquakes and their application to Cascadia and other regions

Science.gov (United States)

Atkinson, G.M.; Boore, D.M.

2003-01-01

Ground-motion relations for earthquakes that occur in subduction zones are an important input to seismic-hazard analyses in many parts of the world. In the Cascadia region (Washington, Oregon, northern California, and British Columbia), for example, there is a significant hazard from megathrust earthquakes along the subduction interface and from large events within the subducting slab. These hazards are in addition to the hazard from shallow earthquakes in the overlying crust. We have compiled a response spectra database from thousands of strong-motion recordings from events of moment magnitude (M) 5-8.3 occurring in subduction zones around the world, including both interface and in-slab events. The 2001 M 6.8 Nisqually and 1999 M 5.9 Satsop earthquakes are included in the database, as are many records from subduction zones in Japan (Kyoshin-Net data), Mexico (Guerrero data), and Central America. The size of the database is four times larger than that available for previous empirical regressions to determine ground-motion relations for subduction-zone earthquakes. The large dataset enables improved determination of attenuation parameters and magnitude scaling, for both interface and in-slab events. Soil response parameters are also better determined by the data. We use the database to develop global ground-motion relations for interface and in-slab earthquakes, using a maximum likelihood regression method. We analyze regional variability of ground-motion amplitudes across the global database and find that there are significant regional differences. In particular, amplitudes in Cascadia differ by more than a factor of 2 from those in Japan for the same magnitude, distance, event type, and National Earthquake Hazards Reduction Program (NEHRP) soil class. This is believed to be due to regional differences in the depth of the soil profile, which are not captured by the NEHRP site classification scheme. Regional correction factors to account for these differences are

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

Digital Repository Service at National Institute of Oceanography (India)

Murthy, K.S.R.

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

Earthquakes: Risk, Monitoring, Notification, and Research

Science.gov (United States)

2008-06-19

States are as much as 30% lower for certain types of ground motion, called long-period seismic waves, which affect taller , multistory buildings. Ground...jump between connected faults. Earthquakes that occur along the Sierra Madre Fault in southern California, for example, could trigger a series of

Comparing population exposure to multiple Washington earthquake scenarios for prioritizing loss estimation studies

Science.gov (United States)

Wood, Nathan J.; Ratliff, Jamie L.; Schelling, John; Weaver, Craig S.

2014-01-01

Scenario-based, loss-estimation studies are useful for gauging potential societal impacts from earthquakes but can be challenging to undertake in areas with multiple scenarios and jurisdictions. We present a geospatial approach using various population data for comparing earthquake scenarios and jurisdictions to help emergency managers prioritize where to focus limited resources on data development and loss-estimation studies. Using 20 earthquake scenarios developed for the State of Washington (USA), we demonstrate how a population-exposure analysis across multiple jurisdictions based on Modified Mercalli Intensity (MMI) classes helps emergency managers understand and communicate where potential loss of life may be concentrated and where impacts may be more related to quality of life. Results indicate that certain well-known scenarios may directly impact the greatest number of people, whereas other, potentially lesser-known, scenarios impact fewer people but consequences could be more severe. The use of economic data to profile each jurisdiction’s workforce in earthquake hazard zones also provides additional insight on at-risk populations. This approach can serve as a first step in understanding societal impacts of earthquakes and helping practitioners to efficiently use their limited risk-reduction resources.

The Temblor mobile seismic risk app, v2: Rapid and seamless earthquake information to inspire individuals to recognize and reduce their risk

Science.gov (United States)

Stein, R. S.; Sevilgen, V.; Sevilgen, S.; Kim, A.; Jacobson, D. S.; Lotto, G. C.; Ely, G.; Bhattacharjee, G.; O'Sullivan, J.

2017-12-01

Temblor quantifies and personalizes earthquake risk and offers solutions by connecting users with qualified retrofit and insurance providers. Temblor's daily blog on current earthquakes, seismic swarms, eruptions, floods, and landslides makes the science accessible to the public. Temblor is available on iPhone, Android, and mobile web app platforms (http://temblor.net). The app presents both scenario (worst case) and probabilistic (most likely) financial losses for homes and commercial buildings, and estimates the impact of seismic retrofit and insurance on the losses and safety. Temblor's map interface has clickable earthquakes (with source parameters and links) and active faults (name, type, and slip rate) around the world, and layers for liquefaction, landslides, tsunami inundation, and flood zones in the U.S. The app draws from the 2014 USGS National Seismic Hazard Model and the 2014 USGS Building Seismic Safety Council ShakeMap scenari0 database. The Global Earthquake Activity Rate (GEAR) model is used worldwide, with active faults displayed in 75 countries. The Temblor real-time global catalog is merged from global and national catalogs, with aftershocks discriminated from mainshocks. Earthquake notifications are issued to Temblor users within 30 seconds of their occurrence, with approximate locations and magnitudes that are rapidly refined in the ensuing minutes. Launched in 2015, Temblor has 650,000 unique users, including 250,000 in the U.S. and 110,000 in Chile, as well as 52,000 Facebook followers. All data shown in Temblor is gathered from authoritative or published sources and is synthesized to be intuitive and actionable to the public. Principal data sources include USGS, FEMA, EMSC, GEM Foundation, NOAA, GNS Science (New Zealand), INGV (Italy), PHIVOLCS (Philippines), GSJ (Japan), Taiwan Earthquake Model, EOS Singapore (Southeast Asia), MTA (Turkey), PB2003 (plate boundaries), CICESE (Baja California), California Geological Survey, and 20 other state

Prediction of the occurrence of related strong earthquakes in Italy

International Nuclear Information System (INIS)

Vorobieva, I.A.; Panza, G.F.

1993-06-01

In the seismic flow it is often observed that a Strong Earthquake (SE), is followed by Related Strong Earthquakes (RSEs), which occur near the epicentre of the SE with origin time rather close to the origin time of the SE. The algorithm for the prediction of the occurrence of a RSE has been developed and applied for the first time to the seismicity data of the California-Nevada region and has been successfully tested in several regions of the World, the statistical significance of the result being 97%. So far, it has been possible to make five successful forward predictions, with no false alarms or failures to predict. The algorithm is applied here to the Italian territory, where the occurrence of RSEs is a particularly rare phenomenon. Our results show that the standard algorithm is successfully directly applicable without any adjustment of the parameters. Eleven SEs are considered. Of them, three are followed by a RSE, as predicted by the algorithm, eight SEs are not followed by a RSE, and the algorithm predicts this behaviour for seven of them, giving rise to only one false alarm. Since, in Italy, quite often the series of strong earthquakes are relatively short, the algorithm has been extended to handle such situation. The result of this experiment indicates that it is possible to attempt to test a SE, for the occurrence of a RSE, soon after the occurrence of the SE itself, performing timely ''preliminary'' recognition on reduced data sets. This fact, the high confidence level of the retrospective analysis, and the first successful forward predictions, made in different parts of the World, indicates that, even if additional tests are desirable, the algorithm can already be considered for routine application to Civil Defence. (author). Refs, 3 figs, 7 tabs

Earthquake Disaster of Yogyakarta and Central Java, and Disaster Reduction, Indonesia

Directory of Open Access Journals (Sweden)

Sutikno Sutikno

2016-05-01

Full Text Available This paper discussed on earthquake disaster and its reduction of Yogyakarta and Central Java, Indonesia. The study area is located at relatively a short distance from subduction zone of India-Australian and Eurasian plates. Geologically this area is characterized by fault and graben structure, and geomorphologically is composed of block mountain, karsts topography and fluvio-volcanic plain. Aim of this paper is to evaluate the spatial distribution of the damage area, the environmental impacts, and to discuss the risk reduction of earthquake disaster scientifically and practically. In this paper to determine the hazard susceptibility zone and their environmental impact used geologic, geomorphologic, land use map, remote sensing image interpretation, and field observation. Discussion on the earthquake disaster risk reduction based on the hazard susceptibility and the characteristic of the human settlement and facilities. The result of this study shows that: i.the high damage area associate with distribution of the fault structures and the lithology; ii. mass-movement, lowering of groundwater, rising new springs, liquefaction, cracking of rocks and land surface; iii. structural non structural efforts are used for earthquake disaster reduction.

1/f and the Earthquake Problem: Scaling constraints that facilitate operational earthquake forecasting

Science.gov (United States)

yoder, M. R.; Rundle, J. B.; Turcotte, D. L.

2012-12-01

The difficulty of forecasting earthquakes can fundamentally be attributed to the self-similar, or "1/f", nature of seismic sequences. Specifically, the rate of occurrence of earthquakes is inversely proportional to their magnitude m, or more accurately to their scalar moment M. With respect to this "1/f problem," it can be argued that catalog selection (or equivalently, determining catalog constraints) constitutes the most significant challenge to seismicity based earthquake forecasting. Here, we address and introduce a potential solution to this most daunting problem. Specifically, we introduce a framework to constrain, or partition, an earthquake catalog (a study region) in order to resolve local seismicity. In particular, we combine Gutenberg-Richter (GR), rupture length, and Omori scaling with various empirical measurements to relate the size (spatial and temporal extents) of a study area (or bins within a study area) to the local earthquake magnitude potential - the magnitude of earthquake the region is expected to experience. From this, we introduce a new type of time dependent hazard map for which the tuning parameter space is nearly fully constrained. In a similar fashion, by combining various scaling relations and also by incorporating finite extents (rupture length, area, and duration) as constraints, we develop a method to estimate the Omori (temporal) and spatial aftershock decay parameters as a function of the parent earthquake's magnitude m. From this formulation, we develop an ETAS type model that overcomes many point-source limitations of contemporary ETAS. These models demonstrate promise with respect to earthquake forecasting applications. Moreover, the methods employed suggest a general framework whereby earthquake and other complex-system, 1/f type, problems can be constrained from scaling relations and finite extents.; Record-breaking hazard map of southern California, 2012-08-06. "Warm" colors indicate local acceleration (elevated hazard

Earthquake potential revealed by tidal influence on earthquake size-frequency statistics

Science.gov (United States)

Ide, Satoshi; Yabe, Suguru; Tanaka, Yoshiyuki

2016-11-01

The possibility that tidal stress can trigger earthquakes is long debated. In particular, a clear causal relationship between small earthquakes and the phase of tidal stress is elusive. However, tectonic tremors deep within subduction zones are highly sensitive to tidal stress levels, with tremor rate increasing at an exponential rate with rising tidal stress. Thus, slow deformation and the possibility of earthquakes at subduction plate boundaries may be enhanced during periods of large tidal stress. Here we calculate the tidal stress history, and specifically the amplitude of tidal stress, on a fault plane in the two weeks before large earthquakes globally, based on data from the global, Japanese, and Californian earthquake catalogues. We find that very large earthquakes, including the 2004 Sumatran, 2010 Maule earthquake in Chile and the 2011 Tohoku-Oki earthquake in Japan, tend to occur near the time of maximum tidal stress amplitude. This tendency is not obvious for small earthquakes. However, we also find that the fraction of large earthquakes increases (the b-value of the Gutenberg-Richter relation decreases) as the amplitude of tidal shear stress increases. The relationship is also reasonable, considering the well-known relationship between stress and the b-value. This suggests that the probability of a tiny rock failure expanding to a gigantic rupture increases with increasing tidal stress levels. We conclude that large earthquakes are more probable during periods of high tidal stress.

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

International Nuclear Information System (INIS)

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

2012-01-01

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

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

Energy Technology Data Exchange (ETDEWEB)

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

2012-03-01

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

The Chiloé Mw 7.6 earthquake of 2016 December 25 in Southern Chile and its relation to the Mw 9.5 1960 Valdivia earthquake

Science.gov (United States)

Lange, Dietrich; Ruiz, Javier; Carrasco, Sebastián; Manríquez, Paula

2018-04-01

On 2016 December 25, an Mw 7.6 earthquake broke a portion of the Southern Chilean subduction zone south of Chiloé Island, located in the central part of the Mw 9.5 1960 Valdivia earthquake. This region is characterized by repeated earthquakes in 1960 and historical times with very sparse interseismic activity due to the subduction of a young (˜15 Ma), and therefore hot, oceanic plate. We estimate the coseismic slip distribution based on a kinematic finite-fault source model, and through joint inversion of teleseismic body waves and strong motion data. The coseismic slip model yields a total seismic moment of 3.94 × 1020 N.m that occurred over ˜30 s, with the rupture propagating mainly downdip, reaching a peak slip of ˜4.2 m. Regional moment tensor inversion of stronger aftershocks reveals thrust type faulting at depths of the plate interface. The fore- and aftershock seismicity is mostly related to the subduction interface with sparse seismicity in the overriding crust. The 2016 Chiloé event broke a region with increased locking and most likely broke an asperity of the 1960 earthquake. The updip limit of the main event, aftershocks, foreshocks and interseismic activity are spatially similar, located ˜15 km offshore and parallel to Chiloé Islands west coast. The coseismic slip model of the 2016 Chiloé earthquake suggests a peak slip of 4.2 m that locally exceeds the 3.38 m slip deficit that has accumulated since 1960. Therefore, the 2016 Chiloé earthquake possibly released strain that has built up prior to the 1960 Valdivia earthquake.

Structural variation along the southwestern Nankai seismogenic zone related to various earthquake phenomena

Science.gov (United States)

Nakanishi, A.; Shimomura, N.; Kodaira, S.; Obana, K.; Takahashi, T.; Yamamoto, Y.; Sato, T.; Kashiwase, K.; Fujimori, H.; Kaneda, Y.; Mochizuki, K.; Kato, A.; Iidaka, T.; Kurashimo, E.; Shinohara, M.; Takeda, T.; Shiomi, K.

2011-12-01

In the Nankai Trough subduction seismogenic zone, the Nankai and Tonankai earthquakes had often occurred simultaneously, and caused a great event. In order to reduce a great deal of damage to coastal area from both strong ground motion and tsunami generation, it is necessary to understand rupture synchronization and segmentation of the Nankai megathrust earthquake. For a precise estimate of the rupture area of the Nankai megathrust event, it is important to know the geometry of the subducting Philippine Sea plate and deep subduction structure along the Nankai Trough. To obtain the deep subduction structure of the coseismic rupture area of the Nankai earthquake in 1946 off Shikoku area, the large-scale high-resolution wide-angle seismic study was conducted in 2009 and 2010. In this study, 201 and 200 ocean bottom seismographs were deployed off the Shikoku Island and the Kii channel respectively. A tuned airgun system (7800 cu. in.) shot every 200m along 13 profiles. Airgun shots were also recorded along an onshore seismic profile (prepared by ERI, univ. of Tokyo and NIED) prolonged from the offshore profile off the Kii Peninsula. Long-term observation was conducted for ~9 months by 21 OBSs off the Shikoku area and 20 OBSs off the Kii channel.This research is part of 'Research concerning Interaction Between the Tokai, Tonankai and Nankai Earthquakes' funded by Ministry of Education, Culture, Sports, Science and Technology, Japan. Structural images of the overriding plate indicate the old accreted sediments (the Cretaceous-Tertiary accretionary prism) with the velocity greater than 6km/s extend seaward from off the Shikoku to the Hyuga-nada. Moreover, the young accreted sediments become relatively thinner eastward from off the cape Ashizuri to Muroto. These structural variations might be related to the different rupture pattern of the Nankai event. Structural image of the deep low frequency earthquakes and tremors is shown by using the airgun shots recorded at onshore

Earthquake Emergency Education in Dushanbe, Tajikistan

Science.gov (United States)

Mohadjer, Solmaz; Bendick, Rebecca; Halvorson, Sarah J.; Saydullaev, Umed; Hojiboev, Orifjon; Stickler, Christine; Adam, Zachary R.

2010-01-01

We developed a middle school earthquake science and hazards curriculum to promote earthquake awareness to students in the Central Asian country of Tajikistan. These materials include pre- and post-assessment activities, six science activities describing physical processes related to earthquakes, five activities on earthquake hazards and mitigation…

Electrocardiographic features of patients with earthquake related posttraumatic stress disorder

Science.gov (United States)

İlhan, Erkan; Kaplan, Abdullah; Güvenç, Tolga Sinan; Biteker, Murat; Karabulut, Evindar; Işıklı, Serhan

2013-01-01

AIM: To analyze electrocardiographic features of patients diagnosed with posttraumatic stress disorder (PTSD) after the Van-Erciş earthquake, with a shock measuring 7.2 on the Richter scale that took place in Turkey in October 2011. METHODS: Surface electrocardiograms of 12 patients with PTSD admitted to Van Erciş State Hospital (Van, Turkey) from February 2012 to May 2012 were examined. Psychiatric interviews of the sex and age matched control subjects, who had experienced the earthquake, confirmed the absence of any known diagnosable psychiatric conditions in the control group. RESULTS: A wide range of electrocardiogram (ECG) parameters, such as P-wave dispersion, QT dispersion, QT interval, Tpeak to Tend interval, intrinsicoid deflection durations and other traditional parameters were similar in both groups. There was no one with an abnormal P wave axis, short or long PR interval, long or short QT interval, negative T wave in lateral leads, abnormal T wave axis, abnormal left or right intrinsicoid deflection duration, low voltage, left bundle branch block, right bundle branch block, left posterior hemiblock, left or right axis deviation, left ventricular hypertrophy, right or left atrial enlargement and pathological q(Q) wave in either group. CONCLUSION: The study showed no direct effect of earthquake related PTSD on surface ECG in young patients. So, we propose that PTSD has no direct effect on surface ECG but may cause electrocardiographic changes indirectly by triggering atherosclerosis and/or contributing to the ongoing atherosclerotic process. PMID:23538549

Stigma in science: the case of earthquake prediction.

Science.gov (United States)

Joffe, Helene; Rossetto, Tiziana; Bradley, Caroline; O'Connor, Cliodhna

2018-01-01

This paper explores how earthquake scientists conceptualise earthquake prediction, particularly given the conviction of six earthquake scientists for manslaughter (subsequently overturned) on 22 October 2012 for having given inappropriate advice to the public prior to the L'Aquila earthquake of 6 April 2009. In the first study of its kind, semi-structured interviews were conducted with 17 earthquake scientists and the transcribed interviews were analysed thematically. The scientists primarily denigrated earthquake prediction, showing strong emotive responses and distancing themselves from earthquake 'prediction' in favour of 'forecasting'. Earthquake prediction was regarded as impossible and harmful. The stigmatisation of the subject is discussed in the light of research on boundary work and stigma in science. The evaluation reveals how mitigation becomes the more favoured endeavour, creating a normative environment that disadvantages those who continue to pursue earthquake prediction research. Recommendations are made for communication with the public on earthquake risk, with a focus on how scientists portray uncertainty. © 2018 The Author(s). Disasters © Overseas Development Institute, 2018.

Health Status and Risk Factors among Adolescent Survivors One Month after the 2014 Ludian Earthquake

Directory of Open Access Journals (Sweden)

Bihan Tang

2015-06-01

Full Text Available Background: An earthquake struck Ludian in Yunnan Province (China on 3 August 2014, resulting in 3143 injuries, 617 deaths, and 112 missing persons. Our study aimed at estimating the health status and associated determinants among adolescent survivors after the Ludian earthquake. Methods: A cross-sectional survey of 845 was conducted at the Ludian No. 1 Middle School. Descriptive statistics, t-tests, ANOVA and stepwise linear regression analysis were used for data analysis. Results: The mean scores on the physical component summary (PCS and mental component summary (MCS were 46.23 (SD = 7.10 and 36.34 (SD = 7.09, respectively. Lower PCS scores in the aftermath of an earthquake were associated with being trapped or in danger, being female, being an ethnic minority, injury to self and house damage, while lower MSC scores were associated with fear during the earthquake, Han ethnicity, death in the family, not being involved in the rescue and low household income. Conclusions: In our study, significant associations between demographic, socio-economic, and trauma-related experiences variables and overall physical and mental health of adolescent survivors were presented. The results of this study help expand our knowledge of health status among adolescent survivors after the Ludian earthquake.

Money matters: Rapid post-earthquake financial decision-making

Science.gov (United States)

Wald, David J.; Franco, Guillermo

2016-01-01

Post-earthquake financial decision-making is a realm beyond that of many people. In the immediate aftermath of a damaging earthquake, billions of dollars of relief, recovery, and insurance funds are in the balance through new financial instruments that allow those with resources to hedge against disasters and those at risk to limit their earthquake losses and receive funds for response and recovery.

Human casualties in earthquakes: Modelling and mitigation

Science.gov (United States)

Spence, R.J.S.; So, E.K.M.

2011-01-01

Earthquake risk modelling is needed for the planning of post-event emergency operations, for the development of insurance schemes, for the planning of mitigation measures in the existing building stock, and for the development of appropriate building regulations; in all of these applications estimates of casualty numbers are essential. But there are many questions about casualty estimation which are still poorly understood. These questions relate to the causes and nature of the injuries and deaths, and the extent to which they can be quantified. This paper looks at the evidence on these questions from recent studies. It then reviews casualty estimation models available, and finally compares the performance of some casualty models in making rapid post-event casualty estimates in recent earthquakes.

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

International Nuclear Information System (INIS)

Georgescu, E.-S.

2002-01-01

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

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.

Radon, gas geochemistry, groundwater, and earthquakes

Energy Technology Data Exchange (ETDEWEB)

King, Chi-Yu [Power Reactor and Nuclear Fuel Development Corp., Tono Geoscience Center, Toki, Gifu (Japan)

1998-12-31

Radon monitoring in groundwater, soil air, and atmosphere has been continued in many seismic areas of the world for earthquake-prediction and active-fault studies. Some recent measurements of radon and other geochemical and hydrological parameters have been made for sufficiently long periods, with reliable instruments, and together with measurements of meteorological variables and solid-earth tides. The resultant data are useful in better distinguishing earthquake-related changes from various background noises. Some measurements have been carried out in areas where other geophysical measurements are being made also. Comparative studies of various kinds of geophysical data are helpful in ascertaining the reality of the earthquake-related and fault-related anomalies and in understanding the underlying mechanisms. Spatial anomalies of radon and other terrestrial gasses have been observed for many active faults. Such observations indicate that gas concentrations are very much site dependent, particularly on fault zones where terrestrial fluids may move vertically. Temporal anomalies have been reliably observed before and after some recent earthquakes, including the 1995 Kobe earthquake, and the general pattern of anomaly occurrence remains the same as observed before: They are recorded at only relatively few sensitive sites, which can be at much larger distances than expected from existing earthquake-source models. The sensitivity of a sensitive site is also found to be changeable with time. These results clearly show the inadequacy of the existing dilatancy-fluid diffusion and elastic-dislocation models for earthquake sources to explain earthquake-related geochemical and geophysical changes recorded at large distances. (J.P.N.)

Implementation of equity in resource allocation for regional earthquake risk mitigation using two-stage stochastic programming.

Science.gov (United States)

Zolfaghari, Mohammad R; Peyghaleh, Elnaz

2015-03-01

This article presents a new methodology to implement the concept of equity in regional earthquake risk mitigation programs using an optimization framework. It presents a framework that could be used by decisionmakers (government and authorities) to structure budget allocation strategy toward different seismic risk mitigation measures, i.e., structural retrofitting for different building structural types in different locations and planning horizons. A two-stage stochastic model is developed here to seek optimal mitigation measures based on minimizing mitigation expenditures, reconstruction expenditures, and especially large losses in highly seismically active countries. To consider fairness in the distribution of financial resources among different groups of people, the equity concept is incorporated using constraints in model formulation. These constraints limit inequity to the user-defined level to achieve the equity-efficiency tradeoff in the decision-making process. To present practical application of the proposed model, it is applied to a pilot area in Tehran, the capital city of Iran. Building stocks, structural vulnerability functions, and regional seismic hazard characteristics are incorporated to compile a probabilistic seismic risk model for the pilot area. Results illustrate the variation of mitigation expenditures by location and structural type for buildings. These expenditures are sensitive to the amount of available budget and equity consideration for the constant risk aversion. Most significantly, equity is more easily achieved if the budget is unlimited. Conversely, increasing equity where the budget is limited decreases the efficiency. The risk-return tradeoff, equity-reconstruction expenditures tradeoff, and variation of per-capita expected earthquake loss in different income classes are also presented. © 2015 Society for Risk Analysis.

Disaster preparedness and response improvement: comparison of the 2010 Haiti earthquake-related diagnoses with baseline medical data.

Science.gov (United States)

van Berlaer, Gerlant; Staes, Tom; Danschutter, Dirk; Ackermans, Ronald; Zannini, Stefano; Rossi, Gabriele; Buyl, Ronald; Gijs, Geert; Debacker, Michel; Hubloue, Ives

2017-10-01

Disaster medicine research generally lacks control groups. This study aims to describe categories of diagnoses encountered by the Belgian First Aid and Support Team after the 2010 Haiti earthquake and extract earthquake-related changes from comparison with comparable baseline data. The hypothesis is that besides earthquake-related trauma, medical problems emerge soon, questioning an appropriate composition of Foreign Medical Teams and Interagency Emergency Health Kits. Using a descriptive cohort study design, diagnoses of patients presenting to the Belgian field hospital were prospectively registered during 4 weeks after the earthquake and compared with those recorded similarly by Médecins Sans Frontières in the same area and time span in previous and later years. Of 7000 triaged postearthquake patients, 3500 were admitted, of whom 2795 were included and analysed. In the fortnight after the earthquake, 90% suffered from injury. In the following fortnight, medical diseases emerged, particularly respiratory (23%) and digestive (14%). More than 53% developed infections within 3 weeks after the event. Médecins Sans Frontières registered 6407 patients in 2009; 6033 in 2011; and 7300 in 2012. A comparison indicates that postearthquake patients suffered significantly less from violence, but more from wounds, respiratory, digestive and ophthalmological diseases. This is the first comparison of postearthquake diagnoses with baseline data. Within 2 weeks after the acute phase of an earthquake, respiratory, digestive and ophthalmological problems will emerge to the prejudice of trauma. This fact should be anticipated when composing Foreign Medical Teams and Interagency Emergency Health Kits to be sent to the disaster site.

Synthetic Earthquake Statistics From Physical Fault Models for the Lower Rhine Embayment

Science.gov (United States)

Brietzke, G. B.; Hainzl, S.; Zöller, G.

2012-04-01

As of today, seismic risk and hazard estimates mostly use pure empirical, stochastic models of earthquake fault systems tuned specifically to the vulnerable areas of interest. Although such models allow for reasonable risk estimates they fail to provide a link between the observed seismicity and the underlying physical processes. Solving a state-of-the-art fully dynamic description set of all relevant physical processes related to earthquake fault systems is likely not useful since it comes with a large number of degrees of freedom, poor constraints on its model parameters and a huge computational effort. Here, quasi-static and quasi-dynamic physical fault simulators provide a compromise between physical completeness and computational affordability and aim at providing a link between basic physical concepts and statistics of seismicity. Within the framework of quasi-static and quasi-dynamic earthquake simulators we investigate a model of the Lower Rhine Embayment (LRE) that is based upon seismological and geological data. We present and discuss statistics of the spatio-temporal behavior of generated synthetic earthquake catalogs with respect to simplification (e.g. simple two-fault cases) as well as to complication (e.g. hidden faults, geometric complexity, heterogeneities of constitutive parameters).

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...

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

Science.gov (United States)

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

2013-12-01

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

Earthquake-induced ground failures in Italy from a reviewed database

Science.gov (United States)

Martino, S.; Prestininzi, A.; Romeo, R. W.

2014-04-01

A database (Italian acronym CEDIT) of earthquake-induced ground failures in Italy is presented, and the related content is analysed. The catalogue collects data regarding landslides, liquefaction, ground cracks, surface faulting and ground changes triggered by earthquakes of Mercalli epicentral intensity 8 or greater that occurred in the last millennium in Italy. As of January 2013, the CEDIT database has been available online for public use (http://www.ceri.uniroma1.it/cn/gis.jsp ) and is presently hosted by the website of the Research Centre for Geological Risks (CERI) of the Sapienza University of Rome. Summary statistics of the database content indicate that 14% of the Italian municipalities have experienced at least one earthquake-induced ground failure and that landslides are the most common ground effects (approximately 45%), followed by ground cracks (32%) and liquefaction (18%). The relationships between ground effects and earthquake parameters such as seismic source energy (earthquake magnitude and epicentral intensity), local conditions (site intensity) and source-to-site distances are also analysed. The analysis indicates that liquefaction, surface faulting and ground changes are much more dependent on the earthquake source energy (i.e. magnitude) than landslides and ground cracks. In contrast, the latter effects are triggered at lower site intensities and greater epicentral distances than the other environmental effects.

Reproductive health and access to healthcare facilities: risk factors for depression and anxiety in women with an earthquake experience.

Science.gov (United States)

Anwar, Jasim; Mpofu, Elias; Matthews, Lynda R; Shadoul, Ahmed Farah; Brock, Kaye E

2011-06-30

The reproductive and mental health of women contributes significantly to their overall well-being. Three of the eight Millennium Development Goals are directly related to reproductive and sexual health while mental disorders make up three of the ten leading causes of disease burden in low and middle-income countries. Among mental disorders, depression and anxiety are two of the most prevalent. In the context of slower progress in achieving Millennium Development Goals in developing countries and the ever-increasing man-made and natural disasters in these areas, it is important to understand the association between reproductive health and mental health among women with post-disaster experiences. This was a cross-sectional study with a sample of 387 women of reproductive age (15-49 years) randomly selected from the October 2005 earthquake affected areas of Pakistan. Data on reproductive health was collected using the Centers for Disease Control reproductive health assessment toolkit. Depression and anxiety were measured using the Hopkins Symptom Checklist-25, while earthquake experiences were captured using the Harvard Trauma Questionnaire. The association of either depression or anxiety with socio-demographic variables, earthquake experiences, reproductive health and access to health facilities was estimated using multivariate logistic regression. Post-earthquake reproductive health events together with economic deprivation, lower family support and poorer access to health care facilities explained a significant proportion of differences in the experiencing of clinical levels of depression and anxiety. For instance, women losing resources for subsistence, separation from family and experiencing reproductive health events such as having a stillbirth, having had an abortion, having had abnormal vaginal discharge or having had genital ulcers, were at significant risk of depression and anxiety. The relationship between women's post-earthquake mental health and

Mental health problems among the survivors in the hard-hit areas of the Yushu earthquake.

Directory of Open Access Journals (Sweden)

Zhen Zhang

Full Text Available BACKGROUND: On April 14, 2010, an earthquake registering 7.1 on the Richter scale shook Qinghai Province in southwest China. The earthquake caused numerous casualties and much damage. The epicenter, Yushu County, suffered the most severe damage. As a part of the psychological relief work, the present study evaluated the mental health statuses of the people affected and identified the mental disorder risk factors related to earthquakes. METHODS: Five hundred and five earthquake survivors living in Yushu County were investigated 3-4 months after the earthquake. Participant demographic data including gender, age, marital status, ethnicity, educational level, and religious beliefs were collected. The Earthquake-Specific Trauma Exposure Indicators assessed the intensity of exposure to trauma during the earthquake. The PTSD Checklist-Civilian version (PCL-C and the Hopkins Symptoms Checklist-25 (HSCL-25 assessed the symptoms and prevalence rates of probable Posttraumatic Stress Disorder (PTSD as well as anxiety and depression, respectively. The Perceived Social Support Scale (PSSS evaluated subjective social support. RESULTS: The prevalence rates of probable PTSD, anxiety, and depression were 33.7%, 43.8% and 38.6%, respectively. Approximately one fifth of participants suffered from all three conditions. Individuals who were female, felt initial fear during the earthquake, and had less social support were the most likely to have poor mental health. CONCLUSIONS: The present study revealed that there are serious mental problems among the hard-hit survivors of the Yushu earthquake. Survivors at high risk for mental disorders should be specifically considered. The present study provides useful information for rebuilding and relief work.

Earthquake Triggering in the September 2017 Mexican Earthquake Sequence

Science.gov (United States)

Fielding, E. J.; Gombert, B.; Duputel, Z.; Huang, M. H.; Liang, C.; Bekaert, D. P.; Moore, A. W.; Liu, Z.; Ampuero, J. P.

2017-12-01

Southern Mexico was struck by four earthquakes with Mw > 6 and numerous smaller earthquakes in September 2017, starting with the 8 September Mw 8.2 Tehuantepec earthquake beneath the Gulf of Tehuantepec offshore Chiapas and Oaxaca. We study whether this M8.2 earthquake triggered the three subsequent large M>6 quakes in southern Mexico to improve understanding of earthquake interactions and time-dependent risk. All four large earthquakes were extensional despite the the subduction of the Cocos plate. The traditional definition of aftershocks: likely an aftershock if it occurs within two rupture lengths of the main shock soon afterwards. Two Mw 6.1 earthquakes, one half an hour after the M8.2 beneath the Tehuantepec gulf and one on 23 September near Ixtepec in Oaxaca, both fit as traditional aftershocks, within 200 km of the main rupture. The 19 September Mw 7.1 Puebla earthquake was 600 km away from the M8.2 shock, outside the standard aftershock zone. Geodetic measurements from interferometric analysis of synthetic aperture radar (InSAR) and time-series analysis of GPS station data constrain finite fault total slip models for the M8.2, M7.1, and M6.1 Ixtepec earthquakes. The early M6.1 aftershock was too close in time and space to the M8.2 to measure with InSAR or GPS. We analyzed InSAR data from Copernicus Sentinel-1A and -1B satellites and JAXA ALOS-2 satellite. Our preliminary geodetic slip model for the M8.2 quake shows significant slip extended > 150 km NW from the hypocenter, longer than slip in the v1 finite-fault model (FFM) from teleseismic waveforms posted by G. Hayes at USGS NEIC. Our slip model for the M7.1 earthquake is similar to the v2 NEIC FFM. Interferograms for the M6.1 Ixtepec quake confirm the shallow depth in the upper-plate crust and show centroid is about 30 km SW of the NEIC epicenter, a significant NEIC location bias, but consistent with cluster relocations (E. Bergman, pers. comm.) and with Mexican SSN location. Coulomb static stress

Foreshock activity and its probabilistic relation to earthquake occurrence in Albania and the surrounding area

Directory of Open Access Journals (Sweden)

K. Irikura

1999-06-01

Full Text Available We investigate some characteristics of foreshock activity of moderate and large earthquakes which occurred in the present century in Albania and the surrounding area. Using a prediction algorithm, based on possible foreshocks, we obtained a probabilistic relation between possible foreshocks and mainshocks. From documentary and instrumental data for the period 1901-1994 for the area between 39.0°- 43.0°N and 18.5°-21.5°E we evaluated the probability of the occurrence of mainshocks immediately after their possible foreshocks. The result shows that the probability that mainshocks with magnitude M ³ 6.0 are preceded by a foreshock with magnitude M ³ 4.4, distance £ about 50 km and time £ 10 days is 38% (6/16. The probability that one earthquake with M ³ 4.4 will be followed by a larger earthquake with M ³ 6.0 within about 50 km and 10 days is 1.3% (6/468, but the probability increases to 33% (1/3 if 7 earthquakes with M ³ 4.4 occur within about 50 km and 10 days. From instrumental data for the period 1971-1994, the probability that mainshocks with M ³ 5.0 are preceded by a foreshock with magnitude M ³ 4.0 is 33% (5/15. The probability that one earthquake with M ³ 4.0 will be followed by a larger earthquake with M ³ 5.0 within about 50 km and 10 days is 1.9% (5/262, but the probability increase to 5.6% (1/18 if 3 earthquakes with M ³ 4.0 occur within about 50 km and 10 days. We also found a regional variation of foreshock activity with activity decreasing from the Vlora-Elbasani-Dibra transversal seismic belt to the Ionian-Adriatic seismic zone to the interior part of Albania seismic zone.

Seismic risk map of Korea

International Nuclear Information System (INIS)

Lee, S.H.; Lee, Y.K.; Eum, S.H.; Yang, S.J.; Chun, M.S.

1983-01-01

A study on seismic hazard level in Korea has been performed and the main results of the study are summarized as follows: 1. Historians suggest that the quality of historical earthquake data may be accurate in some degree and the data should be used in seismic risk analysis. 2. The historical damage events are conformed in historical literatures and their intensities are re-evaluated by joint researchers. The maximum MM intensity of them is VIII evaluated for 17 events. 3. The relation of earthquakes to surface fault is not clear. It seems resonable to related them to tectonic provinces. 4. Statistical seismic risk analysis shows that the acceleration expected within 50O year return period is less than 0.25G when only instrumental earthquakes are used and less than 0.10G if all of instrumental and historical earthquakes are used. The acceleration in Western Coast and Kyungsang area is higher than the other regions in Korea. 5. The maximum horizontal acceleration determined by conservative method is 0.26G when historical earthquake data are used and less than 0.20G if only instrumental earthquakes are used. The return period of 0.26G is 240 years in Kyungsang province and longer in other provinces. (Author)

Lake sediments as natural seismographs: Earthquake-related deformations (seismites) in central Canadian lakes

Science.gov (United States)

Doughty, M.; Eyles, N.; Eyles, C. H.; Wallace, K.; Boyce, J. I.

2014-11-01

Central Canada experiences numerous intraplate earthquakes but their recurrence and source areas remain obscure due to shortness of the instrumental and historic records. Unconsolidated fine-grained sediments in lake basins are 'natural seismographs' with the potential to record ancient earthquakes during the last 10,000 years since the retreat of the Laurentide Ice Sheet. Many lake basins are cut into bedrock and are structurally-controlled by the same Precambrian basement structures (shear zones, terrane boundaries and other lineaments) implicated as the source of ongoing mid-plate earthquake activity. A regional seismic sub-bottom profiling of lakes Gull, Muskoka, Joseph, Rousseau, Ontario, Wanapitei, Fairbanks, Vermilion, Nipissing, Georgian Bay, Mazinaw, Simcoe, Timiskaming, Kipawa, Parry Sound and Lake of Bays, encompassing a total of more than 2000 kilometres of high-resolution track line data supplemented by multibeam and sidescan sonar survey records show a consistent sub-bottom stratigraphy of relatively-thick lowermost lateglacial facies composed of interbedded semi-transparent mass flow facies (debrites, slumps) and rhythmically-laminated silty-clays. Mass flows together with cratered ('kettled') lake floors and associated deformations reflect a dynamic ice-contact glaciolacustrine environment. Exceptionally thick mass flow successions in Lake Timiskaming along the floor of the Timiskaming Graben within the seismically-active Western Quebec Seismic Zone (WQSZ), point to a higher frequency of earthquakes and slope failure during deglaciation and rapid glacio-isostatic rebound though faulting continues into the postglacial. Lateglacial faulting, diapiric deformation and slumping of coeval lateglacial sediments is observed in Parry Sound, Lake Muskoka and Lake Joseph, which are all located above prominent Precambrian terrane boundaries. Lateglacial sediments are sharply overlain by relatively-thin rhythmically-laminated and often semi

Deterministic earthquake scenarios for the city of Sofia

International Nuclear Information System (INIS)

Slavov, S.; Paskaleva, I.; Kouteva, M.; Vaccari, P.; Panza, G.F.

2002-08-01

The city of Sofia is exposed to a high seismic risk. Macroseismic intensities in the range of VIII-X (MSK) can be expected in the city. The earthquakes, that can influence the hazard at Sofia, originate either beneath the city or are caused by seismic sources located within a radius of 40km. The city of Sofia is also prone to the remote Vrancea seismic zone in Romania, and particularly vulnerable are the long - period elements of the built environment. The high seismic risk and the lack of instrumental recordings of the regional seismicity makes the use of appropriate credible earthquake scenarios and ground motion modelling approaches for defining the seismic input for the city of Sofia necessary. Complete synthetic seismic signals, due to several earthquake scenarios, were computed along chosen geological profiles crossing the city, applying a hybrid technique, based on the modal summation technique and finite differences. The modelling takes into account simultaneously the geotechnical properties of the site, the position and geometry of the seismic source and the mechanical properties of the propagation medium. Acceleration, velocity and displacement time histories and related quantities of earthquake engineering interest (e.g. response spectra, ground motion amplification along the profiles) have been supplied. The approach applied in this study allows us to obtain the definition of the seismic input at low cost exploiting large quantities of existing data (e.g. geotechnical, geological, seismological). It may be efficiently used to estimate the ground motion for the purposes of microzonation, urban planning, retrofitting or insurance of the built environment, etc. (author)

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

Science.gov (United States)

Sugimoto, Megumi

2015-04-01

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

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)

Parallelization of the Coupled Earthquake Model

Science.gov (United States)

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

2007-01-01

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

Development of optimization-based probabilistic earthquake scenarios for the city of Tehran

Science.gov (United States)

Zolfaghari, M. R.; Peyghaleh, E.

2016-01-01

This paper presents the methodology and practical example for the application of optimization process to select earthquake scenarios which best represent probabilistic earthquake hazard in a given region. The method is based on simulation of a large dataset of potential earthquakes, representing the long-term seismotectonic characteristics in a given region. The simulation process uses Monte-Carlo simulation and regional seismogenic source parameters to generate a synthetic earthquake catalogue consisting of a large number of earthquakes, each characterized with magnitude, location, focal depth and fault characteristics. Such catalogue provides full distributions of events in time, space and size; however, demands large computation power when is used for risk assessment, particularly when other sources of uncertainties are involved in the process. To reduce the number of selected earthquake scenarios, a mixed-integer linear program formulation is developed in this study. This approach results in reduced set of optimization-based probabilistic earthquake scenario, while maintaining shape of hazard curves and full probabilistic picture by minimizing the error between hazard curves driven by full and reduced sets of synthetic earthquake scenarios. To test the model, the regional seismotectonic and seismogenic characteristics of northern Iran are used to simulate a set of 10,000-year worth of events consisting of some 84,000 earthquakes. The optimization model is then performed multiple times with various input data, taking into account probabilistic seismic hazard for Tehran city as the main constrains. The sensitivity of the selected scenarios to the user-specified site/return period error-weight is also assessed. The methodology could enhance run time process for full probabilistic earthquake studies like seismic hazard and risk assessment. The reduced set is the representative of the contributions of all possible earthquakes; however, it requires far less

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

Science.gov (United States)

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

2009-04-01

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

Hotspots, Lifelines, and the Safrr Haywired Earthquake Sequence

Science.gov (United States)

Ratliff, J. L.; Porter, K.

2014-12-01

Though California has experienced many large earthquakes (San Francisco, 1906; Loma Prieta, 1989; Northridge, 1994), the San Francisco Bay Area has not had a damaging earthquake for 25 years. Earthquake risk and surging reliance on smartphones and the Internet to handle everyday tasks raise the question: is an increasingly technology-reliant Bay Area prepared for potential infrastructure impacts caused by a major earthquake? How will a major earthquake on the Hayward Fault affect lifelines (roads, power, water, communication, etc.)? The U.S. Geological Survey Science Application for Risk Reduction (SAFRR) program's Haywired disaster scenario, a hypothetical two-year earthquake sequence triggered by a M7.05 mainshock on the Hayward Fault, addresses these and other questions. We explore four geographic aspects of lifeline damage from earthquakes: (1) geographic lifeline concentrations, (2) areas where lifelines pass through high shaking or potential ground-failure zones, (3) areas with diminished lifeline service demand due to severe building damage, and (4) areas with increased lifeline service demand due to displaced residents and businesses. Potential mainshock lifeline vulnerability and spatial demand changes will be discerned by superimposing earthquake shaking, liquefaction probability, and landslide probability damage thresholds with lifeline concentrations and with large-capacity shelters. Intersecting high hazard levels and lifeline clusters represent potential lifeline susceptibility hotspots. We will also analyze possible temporal vulnerability and demand changes using an aftershock shaking threshold. The results of this analysis will inform regional lifeline resilience initiatives and response and recovery planning, as well as reveal potential redundancies and weaknesses for Bay Area lifelines. Identified spatial and temporal hotspots can provide stakeholders with a reference for possible systemic vulnerability resulting from an earthquake sequence.

A quick earthquake disaster loss assessment method supported by dasymetric data for emergency response in China

Science.gov (United States)

Xu, Jinghai; An, Jiwen; Nie, Gaozong

2016-04-01

Improving earthquake disaster loss estimation speed and accuracy is one of the key factors in effective earthquake response and rescue. The presentation of exposure data by applying a dasymetric map approach has good potential for addressing this issue. With the support of 30'' × 30'' areal exposure data (population and building data in China), this paper presents a new earthquake disaster loss estimation method for emergency response situations. This method has two phases: a pre-earthquake phase and a co-earthquake phase. In the pre-earthquake phase, we pre-calculate the earthquake loss related to different seismic intensities and store them in a 30'' × 30'' grid format, which has several stages: determining the earthquake loss calculation factor, gridding damage probability matrices, calculating building damage and calculating human losses. Then, in the co-earthquake phase, there are two stages of estimating loss: generating a theoretical isoseismal map to depict the spatial distribution of the seismic intensity field; then, using the seismic intensity field to extract statistics of losses from the pre-calculated estimation data. Thus, the final loss estimation results are obtained. The method is validated by four actual earthquakes that occurred in China. The method not only significantly improves the speed and accuracy of loss estimation but also provides the spatial distribution of the losses, which will be effective in aiding earthquake emergency response and rescue. Additionally, related pre-calculated earthquake loss estimation data in China could serve to provide disaster risk analysis before earthquakes occur. Currently, the pre-calculated loss estimation data and the two-phase estimation method are used by the China Earthquake Administration.

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.

Spatio-temporal earthquake risk assessment for the Lisbon Metropolitan Area - A contribution to improving standard methods of population exposure and vulnerability analysis

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Freire, Sérgio; Aubrecht, Christoph

2010-05-01

The recent 7.0 M earthquake that caused severe damage and destruction in parts of Haiti struck close to 5 PM (local time), at a moment when many people were not in their residences, instead being in their workplaces, schools, or churches. Community vulnerability assessment to seismic hazard relying solely on the location and density of resident-based census population, as is commonly the case, would grossly misrepresent the real situation. In particular in the context of global (climate) change, risk analysis is a research field increasingly gaining in importance whereas risk is usually defined as a function of hazard probability and vulnerability. Assessment and mapping of human vulnerability has however generally been lagging behind hazard analysis efforts. Central to the concept of vulnerability is the issue of human exposure. Analysis of exposure is often spatially tied to administrative units or reference objects such as buildings, spanning scales from the regional level to local studies for small areas. Due to human activities and mobility, the spatial distribution of population is time-dependent, especially in metropolitan areas. Accurately estimating population exposure is a key component of catastrophe loss modeling, one element of effective risk analysis and emergency management. Therefore, accounting for the spatio-temporal dynamics of human vulnerability correlates with recent recommendations to improve vulnerability analyses. Earthquakes are the prototype for a major disaster, being low-probability, rapid-onset, high-consequence events. Lisbon, Portugal, is subject to a high risk of earthquake, which can strike at any day and time, as confirmed by modern history (e.g. December 2009). The recently-approved Special Emergency and Civil Protection Plan (PEERS) is based on a Seismic Intensity map, and only contemplates resident population from the census as proxy for human exposure. In the present work we map and analyze the spatio-temporal distribution of

Earthquake Safety Tips in the Classroom

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Melo, M. O.; Maciel, B. A. P. C.; Neto, R. P.; Hartmann, R. P.; Marques, G.; Gonçalves, M.; Rocha, F. L.; Silveira, G. M.

2014-12-01

The catastrophes induced by earthquakes are among the most devastating ones, causing an elevated number of human losses and economic damages. But, we have to keep in mind that earthquakes don't kill people, buildings do. Earthquakes can't be predicted and the only way of dealing with their effects is to teach the society how to be prepared for them, and how to deal with their consequences. In spite of being exposed to moderate and large earthquakes, most of the Portuguese are little aware of seismic risk, mainly due to the long recurrence intervals between strong events. The acquisition of safe and correct attitudes before, during and after an earthquake is relevant for human security. Children play a determinant role in the establishment of a real and long-lasting "culture of prevention", both through action and new attitudes. On the other hand, when children assume correct behaviors, their relatives often change their incorrect behaviors to mimic the correct behaviors of their kids. In the framework of a Parents-in-Science initiative, we started with bi-monthly sessions for children aged 5 - 6 years old and 9 - 10 years old. These sessions, in which parents, teachers and high-school students participate, became part of the school's permanent activities. We start by a short introduction to the Earth and to earthquakes by story telling and by using simple science activities to trigger children curiosity. With safety purposes, we focus on how crucial it is to know basic information about themselves and to define, with their families, an emergency communications plan, in case family members are separated. Using a shaking table we teach them how to protect themselves during an earthquake. We then finish with the preparation on an individual emergency kit. This presentation will highlight the importance of encouraging preventive actions in order to reduce the impact of earthquakes on society. This project is developed by science high-school students and teachers, in

OMG Earthquake! Can Twitter improve earthquake response?

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Earle, P. S.; Guy, M.; Ostrum, C.; Horvath, S.; Buckmaster, R. A.

2009-12-01

The U.S. Geological Survey (USGS) is investigating how the social networking site Twitter, a popular service for sending and receiving short, public, text messages, can augment its earthquake response products and the delivery of hazard information. The goal is to gather near real-time, earthquake-related messages (tweets) and provide geo-located earthquake detections and rough maps of the corresponding felt areas. Twitter and other social Internet technologies are providing the general public with anecdotal earthquake hazard information before scientific information has been published from authoritative sources. People local to an event often publish information within seconds via these technologies. In contrast, depending on the location of the earthquake, scientific alerts take between 2 to 20 minutes. Examining the tweets following the March 30, 2009, M4.3 Morgan Hill earthquake shows it is possible (in some cases) to rapidly detect and map the felt area of an earthquake using Twitter responses. Within a minute of the earthquake, the frequency of “earthquake” tweets rose above the background level of less than 1 per hour to about 150 per minute. Using the tweets submitted in the first minute, a rough map of the felt area can be obtained by plotting the tweet locations. Mapping the tweets from the first six minutes shows observations extending from Monterey to Sacramento, similar to the perceived shaking region mapped by the USGS “Did You Feel It” system. The tweets submitted after the earthquake also provided (very) short first-impression narratives from people who experienced the shaking. Accurately assessing the potential and robustness of a Twitter-based system is difficult because only tweets spanning the previous seven days can be searched, making a historical study impossible. We have, however, been archiving tweets for several months, and it is clear that significant limitations do exist. The main drawback is the lack of quantitative information

Ionospheric anomalies detected by ionosonde and possibly related to crustal earthquakes in Greece

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Perrone, Loredana; De Santis, Angelo; Abbattista, Cristoforo; Alfonsi, Lucilla; Amoruso, Leonardo; Carbone, Marianna; Cesaroni, Claudio; Cianchini, Gianfranco; De Franceschi, Giorgiana; De Santis, Anna; Di Giovambattista, Rita; Marchetti, Dedalo; Pavòn-Carrasco, Francisco J.; Piscini, Alessandro; Spogli, Luca; Santoro, Francesca

2018-03-01

Ionosonde data and crustal earthquakes with magnitude M ≥ 6.0 observed in Greece during the 2003-2015 period were examined to check if the relationships obtained earlier between precursory ionospheric anomalies and earthquakes in Japan and central Italy are also valid for Greek earthquakes. The ionospheric anomalies are identified on the observed variations of the sporadic E-layer parameters (h'Es, foEs) and foF2 at the ionospheric station of Athens. The corresponding empirical relationships between the seismo-ionospheric disturbances and the earthquake magnitude and the epicentral distance are obtained and found to be similar to those previously published for other case studies. The large lead times found for the ionospheric anomalies occurrence may confirm a rather long earthquake preparation period. The possibility of using the relationships obtained for earthquake prediction is finally discussed.

Ionospheric anomalies detected by ionosonde and possibly related to crustal earthquakes in Greece

Directory of Open Access Journals (Sweden)

L. Perrone

2018-03-01

Full Text Available Ionosonde data and crustal earthquakes with magnitude M ≥ 6.0 observed in Greece during the 2003–2015 period were examined to check if the relationships obtained earlier between precursory ionospheric anomalies and earthquakes in Japan and central Italy are also valid for Greek earthquakes. The ionospheric anomalies are identified on the observed variations of the sporadic E-layer parameters (h′Es, foEs and foF2 at the ionospheric station of Athens. The corresponding empirical relationships between the seismo-ionospheric disturbances and the earthquake magnitude and the epicentral distance are obtained and found to be similar to those previously published for other case studies. The large lead times found for the ionospheric anomalies occurrence may confirm a rather long earthquake preparation period. The possibility of using the relationships obtained for earthquake prediction is finally discussed.

Developing a new perspective to study the health of survivors of Sichuan earthquakes in China: a study on the effect of post-earthquake rescue policies on survivors' health-related quality of life.

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Liang, Ying; Wang, Xiukun

2013-10-29

Sichuan is a province in China with an extensive history of earthquakes. Recent earthquakes, including the Lushan earthquake in 2013, have resulted in thousands of people losing their homes and their families. However, there is a research gap on the efficiency of government support policies. Therefore, this study develops a new perspective to study the health of earthquake survivors, based on the effect of post-earthquake rescue policies on health-related quality of life (HRQOL) of survivors of the Sichuan earthquake. This study uses data from a survey conducted in five hard-hit counties (Wenchuan, Qingchuan, Mianzhu, Lushan, and Dujiangyan) in Sichuan in 2013. A total of 2,000 questionnaires were distributed, and 1,672 were returned; the response rate was 83.6%. Results of the rescue policies scale and Medical Outcomes Study Short Form 36 (SF-36) scale passed the reliability test. The confirmatory factor analysis model showed that the physical component summary (PCS) directly affected the mental component summary (MCS). The results of structural equation model regarding the effects of rescue policies on HRQOL showed that the path coefficients of six policies (education, orphans, employment, poverty, legal, and social rescue policies) to the PCS of survivors were all positive and passed the test of significance. Finally, although only the path coefficient of the educational rescue policy to the MCS of survivors was positive and passed the test of significance, the other five policies affected the MCS indirectly through the PCS. The general HRQOL of survivors is not ideal; the survivors showed a low satisfaction with the post-earthquake rescue policies. Further, the six post-earthquake rescue policies significantly improved the HRQOL of survivors and directly affected the promotion of the PCS of survivors. Aside from the educational rescue policy, all other policies affected the MCS indirectly through the PCS. This finding indicates relatively large differences in

Temporal variation of gravity field prior to the Ludian Ms6.5 and Kangding Ms6.3 earthquakes

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Hongtao Hao

2015-11-01

Full Text Available Using mobile gravity data from the central area of Sichuan and Yunnan Provinces, the relationship between gravity variation and earthquakes was studied based on the Ludian Ms6.5 earthquake that occurred on August 3rd, 2014, and the Kangding Ms6.3 earthquake that occurred on November 22nd, 2014; the mechanism of gravity variation was also explored. The results are as follows: (1 Prior to both earthquakes, gravity variation exhibited similar characteristics as those observed before both the Tangshan and Wenchuan earthquakes, in which typical precursor anomalies were positive gravity variation near the epicenter and the occurrence of a high-gravity-gradient zone across the epicenter prior to the earthquake. (2 A relatively accurate prediction of the occurrence locations of the two earthquakes was made by the Gravity Network Center of China (GNCC based on these precursor anomalies. In the gravity study report on the 2014 earthquake trends submitted at the end of 2013, the Daofu-Shimian section at the junction of the Xianshuihe and Longmenshan fault zones was noted as an earthquake-risk region with a predicted magnitude of 6.5, which covered the epicenter of the Kangding Ms6.3 earthquake. In another report on earthquake trends in southwestern China submitted in mid-2014, the Lianfeng, Zhaotong fault zone was also classified as an earthquake-risk region with a magnitude of 6.0, and the central area of this region basically overlapped with the epicenter of the Ludian Ms6.5 earthquake. (3 The gravity variation characteristics are reasonably consistent with crustal movements, and deep material migration is likely the primary cause of gravity variation.

Realization of Earthquake Vulnerability Analysis in Structure Scale with Fuzzy Logic Method in GIS: Kadikoy, Maltepe and Prince Islands Sample

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Alper Şen

2016-12-01

Full Text Available The inadequate evaluation of geologic factors and unqualified and unplanned structuring play effective role in giant damage and loss of lives created by the earthquakes and faulty areas choice and structure construction cause building damages during the earthquake, thus it also causes giant loss of lives. Istanbul province and its immediate environment are located in north of North Anatolian Fault Zone having 1500 km length. Hence, it causes that the settlement’s Sea of Marmara coastal region is located in 1st seismic belt. The earthquake risk in Istanbul and related risk factors should be determined besides vulnerability and earthquake risk. A mathematical model has been created in geographic information systems for Kadıkoy, Maltepe and Prince Islands sub-provinces by using Fuzzy Logic method which is one of the artificial intelligence methods by considering 4 vulnerability parameters and earthquake vulnerability analysis have been made in this study. The used parameters are the location by fault line, geologic structure, building structure and the number of floors. The vulnerability grades emerged as a result of analysis have been studied and the distribution of buildings according to those levels have been presented via a thematic map. The pre-earthquake precautions should be determined for the study field by considering the vulnerability grades in case of any earthquake and the loss of life and property should be minimized.

Offshore Earthquakes Do Not Influence Marine Mammal Stranding Risk on the Washington and Oregon Coasts

Science.gov (United States)

Grant, Rachel A.; Savirina, Anna

2018-01-01

Simple Summary Marine mammals stranding on coastal beaches is not unusual. However, there appears to be no single cause for this, with several causes being probable, such as starvation, contact with humans (for example boat strike or entanglement with fishing gear), disease, and parasitism. We evaluated marine mammal stranding off the Washington and Oregon coasts and looked at offshore earthquakes as a possible contributing factor. Our analysis showed that offshore earthquakes did not make marine mammals more likely to strand. We also analysed a subset of data from the north of Washington State and found that non-adult animals made up a large proportion of stranded animals, and for dead animals the commonest cause of death was disease, traumatic injury, or starvation. Abstract The causes of marine mammals stranding on coastal beaches are not well understood, but may relate to topography, currents, wind, water temperature, disease, toxic algal blooms, and anthropogenic activity. Offshore earthquakes are a source of intense sound and disturbance and could be a contributing factor to stranding probability. We tested the hypothesis that the probability of marine mammal stranding events on the coasts of Washington and Oregon, USA is increased by the occurrence of offshore earthquakes in the nearby Cascadia subduction zone. The analysis carried out here indicated that earthquakes are at most, a very minor predictor of either single, or large (six or more animals) stranding events, at least for the study period and location. We also tested whether earthquakes inhibit stranding and again, there was no link. Although we did not find a substantial association of earthquakes with strandings in this study, it is likely that there are many factors influencing stranding of marine mammals and a single cause is unlikely to be responsible. Analysis of a subset of data for which detailed descriptions were available showed that most live stranded animals were pups, calves, or

The severity of an earthquake

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,

1997-01-01

The severity of an earthquake can be expressed in terms of both intensity and magnitude. However, the two terms are quite different, and they are often confused. Intensity is based on the observed effects of ground shaking on people, buildings, and natural features. It varies from place to place within the disturbed region depending on the location of the observer with respect to the earthquake epicenter. Magnitude is related to the amount of seismic energy released at the hypocenter of the earthquake. It is based on the amplitude of the earthquake waves recorded on instruments

Napa Earthquake impact on water systems

Science.gov (United States)

Wang, J.

2014-12-01

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

Mapping individuals' earthquake preparedness in China

Science.gov (United States)

Wu, Guochun; Han, Ziqiang; Xu, Weijin; Gong, Yue

2018-05-01

Disaster preparedness is critical for reducing potential impact. This paper contributes to current knowledge of disaster preparedness using representative national sample data from China, which faces high earthquake risks in many areas of the country. The adoption of earthquake preparedness activities by the general public, including five indicators of material preparedness and five indicators of awareness preparedness, were surveyed and 3245 respondents from all 31 provinces of Mainland China participated in the survey. Linear regression models and logit regression models were used to analyze the effects of potential influencing factors. Overall, the preparedness levels are not satisfied, with a material preparation score of 3.02 (1-5), and awareness preparation score of 2.79 (1-5), nationally. Meanwhile, residents from western China, which has higher earthquake risk, have higher degrees of preparedness. The concern for disaster risk reduction (DRR) and the concern for building safety and participation in public affairs are consistent positive predictors of both material and awareness preparedness. The demographic and socioeconomic variables' effects, such as gender, age, education, income, urban/rural division, and building size, vary according to different preparedness activities. Finally, the paper concludes with a discussion of the theoretical contribution and potential implementation.

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

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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.

Resilience of aging populations after devastating earthquake event and its determinants - A case study of the Chi-Chi earthquake in Taiwan

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Hung, Chih-Hsuan; Hung, Hung-Chih

2016-04-01

1.Background Major portions of urban areas in Asia are highly exposed and vulnerable to devastating earthquakes. Many studies identify ways to reduce earthquake risk by concentrating more on building resilience for the particularly vulnerable populations. By 2020, as the United Nations' warning, many Asian countries would become 'super-aged societies', such as Taiwan. However, local authorities rarely use resilience approach to frame earthquake disaster risk management and land use strategies. The empirically-based research about the resilience of aging populations has also received relatively little attention. Thus, a challenge arisen for decision-makers is how to enhance resilience of aging populations within the context of risk reduction. This study aims to improve the understanding of the resilience of aging populations and its changes over time in the aftermath of a destructive earthquake at the local level. A novel methodology is proposed to assess the resilience of aging populations and to characterize their changes of spatial distribution patterns, as well as to examine their determinants. 2.Methods and data An indicator-based assessment framework is constructed with the goal of identifying composite indicators (including before, during and after a disaster) that could serve as proxies for attributes of the resilience of aging populations. Using the recovery process of the Chi-Chi earthquake struck central Taiwan in 1999 as a case study, we applied a method combined a geographical information system (GIS)-based spatial statistics technique and cluster analysis to test the extent of which the resilience of aging populations is spatially autocorrelated throughout the central Taiwan, and to explain why clustering of resilient areas occurs in specific locations. Furthermore, to scrutinize the affecting factors of resilience, we develop an aging population resilience model (APRM) based on existing resilience theory. Using the APRM, we applied a multivariate

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.

Global assessment of human losses due to earthquakes

Science.gov (United States)

Silva, Vitor; Jaiswal, Kishor; Weatherill, Graeme; Crowley, Helen

2014-01-01

Current studies have demonstrated a sharp increase in human losses due to earthquakes. These alarming levels of casualties suggest the need for large-scale investment in seismic risk mitigation, which, in turn, requires an adequate understanding of the extent of the losses, and location of the most affected regions. Recent developments in global and uniform datasets such as instrumental and historical earthquake catalogues, population spatial distribution and country-based vulnerability functions, have opened an unprecedented possibility for a reliable assessment of earthquake consequences at a global scale. In this study, a uniform probabilistic seismic hazard assessment (PSHA) model was employed to derive a set of global seismic hazard curves, using the open-source software OpenQuake for seismic hazard and risk analysis. These results were combined with a collection of empirical fatality vulnerability functions and a population dataset to calculate average annual human losses at the country level. The results from this study highlight the regions/countries in the world with a higher seismic risk, and thus where risk reduction measures should be prioritized.

Long-term impact of earthquakes on sleep quality.

Science.gov (United States)

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

2013-01-01

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

Earthquake Early Warning: User Education and Designing Effective Messages

Science.gov (United States)

Burkett, E. R.; Sellnow, D. D.; Jones, L.; Sellnow, T. L.

2014-12-01

The U.S. Geological Survey (USGS) and partners are transitioning from test-user trials of a demonstration earthquake early warning system (ShakeAlert) to deciding and preparing how to implement the release of earthquake early warning information, alert messages, and products to the public and other stakeholders. An earthquake early warning system uses seismic station networks to rapidly gather information about an occurring earthquake and send notifications to user devices ahead of the arrival of potentially damaging ground shaking at their locations. Earthquake early warning alerts can thereby allow time for actions to protect lives and property before arrival of damaging shaking, if users are properly educated on how to use and react to such notifications. A collaboration team of risk communications researchers and earth scientists is researching the effectiveness of a chosen subset of potential earthquake early warning interface designs and messages, which could be displayed on a device such as a smartphone. Preliminary results indicate, for instance, that users prefer alerts that include 1) a map to relate their location to the earthquake and 2) instructions for what to do in response to the expected level of shaking. A number of important factors must be considered to design a message that will promote appropriate self-protective behavior. While users prefer to see a map, how much information can be processed in limited time? Are graphical representations of wavefronts helpful or confusing? The most important factor to promote a helpful response is the predicted earthquake intensity, or how strong the expected shaking will be at the user's location. Unlike Japanese users of early warning, few Californians are familiar with the earthquake intensity scale, so we are exploring how differentiating instructions between intensity levels (e.g., "Be aware" for lower shaking levels and "Drop, cover, hold on" at high levels) can be paired with self-directed supplemental

A new strategy for earthquake focal mechanisms using waveform-correlation-derived relative polarities and cluster analysis: Application to the 2014 Long Valley Caldera earthquake swarm

Science.gov (United States)

Shelly, David R.; Hardebeck, Jeanne L.; Ellsworth, William L.; Hill, David P.

2016-01-01

In microseismicity analyses, reliable focal mechanisms can typically be obtained for only a small subset of located events. We address this limitation here, presenting a framework for determining robust focal mechanisms for entire populations of very small events. To achieve this, we resolve relative P and S wave polarities between pairs of waveforms by using their signed correlation coefficients—a by-product of previously performed precise earthquake relocation. We then use cluster analysis to group events with similar patterns of polarities across the network. Finally, we apply a standard mechanism inversion to the grouped data, using either catalog or correlation-derived P wave polarity data sets. This approach has great potential for enhancing analyses of spatially concentrated microseismicity such as earthquake swarms, mainshock-aftershock sequences, and industrial reservoir stimulation or injection-induced seismic sequences. To demonstrate its utility, we apply this technique to the 2014 Long Valley Caldera earthquake swarm. In our analysis, 85% of the events (7212 out of 8494 located by Shelly et al. [2016]) fall within five well-constrained mechanism clusters, more than 12 times the number with network-determined mechanisms. Of the earthquakes we characterize, 3023 (42%) have magnitudes smaller than 0.0. We find that mechanism variations are strongly associated with corresponding hypocentral structure, yet mechanism heterogeneity also occurs where it cannot be resolved by hypocentral patterns, often confined to small-magnitude events. Small (5–20°) rotations between mechanism orientations and earthquake location trends persist when we apply 3-D velocity models and might reflect a geometry of en echelon, interlinked shear, and dilational faulting.

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.

Earthquake related displacement fields near underground facilities

International Nuclear Information System (INIS)

Pratt, H.R.; Zandt, G.; Bouchon, M.

1979-04-01

Relative displacements of rock masses are evaluated in terms of geological evidence, seismological evidence, data from simulation experiments, and analytical predictive models. Numerical models have been developed to determine displacement fields as a function of depth, distance, and azimuth from an earthquake source. Computer calculations for several types of faults indicate that displacements decrease rapidly with distance from the fault, but that displacements can either increase or decrease as a function of depth depending on the type and geometry of the fault. For long shallow vertical strike-slip faults the displacement decreases markedly with depth. For square strike slip faults and for dip slip faults displacement does not decrease as markedly with depth. Geologic structure, material properties, and depth affect the seismic source spectrum. Amplification of the high frequencies of shear waves is larger by a factor of about 2 for layered geologic models than for an elastic half space

Earthquake likelihood model testing

Science.gov (United States)

Schorlemmer, D.; Gerstenberger, M.C.; Wiemer, S.; Jackson, D.D.; Rhoades, D.A.

2007-01-01

INTRODUCTIONThe Regional Earthquake Likelihood Models (RELM) project aims to produce and evaluate alternate models of earthquake potential (probability per unit volume, magnitude, and time) for California. Based on differing assumptions, these models are produced to test the validity of their assumptions and to explore which models should be incorporated in seismic hazard and risk evaluation. Tests based on physical and geological criteria are useful but we focus on statistical methods using future earthquake catalog data only. We envision two evaluations: a test of consistency with observed data and a comparison of all pairs of models for relative consistency. Both tests are based on the likelihood method, and both are fully prospective (i.e., the models are not adjusted to fit the test data). To be tested, each model must assign a probability to any possible event within a specified region of space, time, and magnitude. For our tests the models must use a common format: earthquake rates in specified “bins” with location, magnitude, time, and focal mechanism limits.Seismology cannot yet deterministically predict individual earthquakes; however, it should seek the best possible models for forecasting earthquake occurrence. This paper describes the statistical rules of an experiment to examine and test earthquake forecasts. The primary purposes of the tests described below are to evaluate physical models for earthquakes, assure that source models used in seismic hazard and risk studies are consistent with earthquake data, and provide quantitative measures by which models can be assigned weights in a consensus model or be judged as suitable for particular regions.In this paper we develop a statistical method for testing earthquake likelihood models. A companion paper (Schorlemmer and Gerstenberger 2007, this issue) discusses the actual implementation of these tests in the framework of the RELM initiative.Statistical testing of hypotheses is a common task and a

ON THE RELATION BETWEEN EARTHQUAKE AND ATMOSPHERIC ELECTRICITY

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Kuznetsov V.V.

2017-07-01

Full Text Available The change in the magnitude of the atmospheric electric field (AEF before the earthquake and immediately after it, according to our model, is due to the fact that the protons of water atmospheric complexes turn out to be quantum-entangled to protons of hydrogen bonds (HB in lithosphere material. After the establishment of the quantum entanglement regime in the system, a decoherence follows. It manifests itself in AEF change, and then there is a recoherence, during which the quantum entanglement of the largest possible number of elements in the system with HB which ends with a new decoherence, is again tuned in the system. It is during this process that a shock wave or an earthquake entailing the change of AEF magnitude is generated.

Prevent recurrence of nuclear disaster (3). Agenda on nuclear safety from earthquake engineering

International Nuclear Information System (INIS)

Kameda, Hiroyuki; Takada, Tsuyoshi; Ebisawa, Katsumi; Nakamura, Susumu

2012-01-01

Based on results of activities of committee on seismic safety of nuclear power plants (NPPs) of Japan Association for Earthquake Engineering, which started activities after Chuetsu-oki earthquake and then experienced Great East Japan Earthquake, (under close collaboration with the committee of Atomic Energy Society of Japan started activities simultaneously), and taking account of further development of concept, agenda on nuclear safety were proposed from earthquake engineering. In order to prevent recurrence of nuclear disaster, individual technical issues of earthquake engineering and comprehensive issues of integration technology, multidisciplinary collaboration and establishment of technology governance based on them were of prime importance. This article described important problems to be solved; (1) technical issues and mission of seismic safety of NPPs, (2) decision making based on risk assessment - basis of technical governance, (3) framework of risk, design and regulation - framework of required technology governance, (4) technical issues of earthquake engineering for nuclear safety, (5) role of earthquake engineering in nuclear power risk communication and (6) importance of multidisciplinary collaboration. Responsibility of engineering would be attributed to establishment of technology governance, cultivation of individual technology and integration technology, and social communications. (T. Tanaka)

Earthquake engineering for nuclear facilities

CERN Document Server

Kuno, Michiya

2017-01-01

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

Precisely locating the Klamath Falls, Oregon, earthquakes

Science.gov (United States)

Qamar, A.; Meagher, K.L.

1993-01-01

The Klamath Falls earthquakes on September 20, 1993, were the largest earthquakes centered in Oregon in more than 50 yrs. Only the magnitude 5.75 Milton-Freewater earthquake in 1936, which was centered near the Oregon-Washington border and felt in an area of about 190,000 sq km, compares in size with the recent Klamath Falls earthquakes. Although the 1993 earthquakes surprised many local residents, geologists have long recognized that strong earthquakes may occur along potentially active faults that pass through the Klamath Falls area. These faults are geologically related to similar faults in Oregon, Idaho, and Nevada that occasionally spawn strong earthquakes. 

Varenna workshop report. Operational earthquake forecasting and decision making

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Warner Marzocchi

2015-09-01

Full Text Available A workshop on Operational earthquake forecasting and decision making was convened in Varenna, Italy, on June 8-11, 2014, under the sponsorship of the EU FP 7 REAKT (Strategies and tools for Real-time EArthquake risK reducTion project, the Seismic Hazard Center at the Istituto Nazionale di Geofisica e Vulcanologia (INGV, and the Southern California Earthquake Center (SCEC. The main goal was to survey the interdisciplinary issues of operational earthquake forecasting (OEF, including the problems that OEF raises for decision making and risk communication. The workshop was attended by 64 researchers from universities, research centers, and governmental institutions in 11 countries. Participants and the workshop agenda are listed in the appendix.The workshop comprised six topical sessions structured around three main themes: the science of operational earthquake forecasting, decision making in a low-probability environment, and communicating hazard and risk. Each topic was introduced by a moderator and surveyed by a few invited speakers, who were then empaneled for an open discussion. The presentations were followed by poster sessions. During a wrap-up session on the last day, the reporters for each topical session summarized the main points that they had gleaned from the talks and open discussions. This report attempts to distill this workshop record into a brief overview of the workshop themes and to describe the range of opinions expressed during the discussions.

The changing health priorities of earthquake response and implications for preparedness: a scoping review.

Science.gov (United States)

Cartwright, C; Hall, M; Lee, A C K

2017-09-01

Earthquakes have substantial impacts on mortality in low- and middle-income countries (LMIC). The academic evidence base to support Disaster Risk Reduction activities in LMIC settings is, however, limited. We sought to address this gap by identifying the health and healthcare impacts of earthquakes in LMICs and to identify the implications of these findings for future earthquake preparedness. Scoping review. A scoping review was undertaken with systematic searches of indexed databases to identify relevant literature. Key study details, findings, recommendations or lessons learnt were extracted and analysed across individual earthquake events. Findings were categorised by time frame relative to earthquakes and linked to the disaster preparedness cycle, enabling a profile of health and healthcare impacts and implications for future preparedness to be established. Health services need to prepare for changing health priorities with a shift from initial treatment of earthquake-related injuries to more general health needs occurring within the first few weeks. Preparedness is required to address mental health and rehabilitation needs in the medium to longer term. Inequalities of the impact of earthquakes on health were noted in particular for women, children, the elderly, disabled and rural communities. The need to maintain access to essential services such as reproductive health and preventative health services were identified. Key preparedness actions include identification of appropriate leaders, planning and training of staff. Testing of plans was advocated within the literature with evidence that this is possible in LMIC settings. Whilst there are a range of health and healthcare impacts of earthquakes, common themes emerged in different settings and from different earthquake events. Preparedness of healthcare systems is essential and possible, in order to mitigate the adverse health impacts of earthquakes in LMIC settings. Preparedness is needed at the community

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.

Living with earthquakes - development and usage of earthquake-resistant construction methods in European and Asian Antiquity

Science.gov (United States)

Kázmér, Miklós; Major, Balázs; Hariyadi, Agus; Pramumijoyo, Subagyo; Ditto Haryana, Yohanes

2010-05-01

outermost layer was treated this way, the core of the shrines was made of simple rectangular blocks. The system resisted both in-plane and out-of-plane shaking quite well, as proven by survival of many shrines for more than a millennium, and by fracturing of blocks instead of displacement during the 2006 Yogyakarta earthquake. Systematic use or disuse of known earthquake-resistant techniques in any one society depends on the perception of earthquake risk and on available financial resources. Earthquake-resistant construction practice is significantly more expensive than regular construction. Perception is influenced mostly by short individual and longer social memory. If earthquake recurrence time is longer than the preservation of social memory, if damaging quakes fade into the past, societies commit the same construction mistakes again and again. Length of the memory is possibly about a generation's lifetime. Events occurring less frequently than 25-30 years can be readily forgotten, and the risk of recurrence considered as negligible, not worth the costs of safe construction practices. (Example of recurring flash floods in Hungary.) Frequent earthquakes maintain safe construction practices, like the Java masonry technique throughout at least two centuries, and like the Fachwerk tradition on Modern Aegean Samos throughout 500 years of political and technological development. (OTKA K67583)

Awareness and understanding of earthquake hazards at school

Science.gov (United States)

Saraò, Angela; Peruzza, Laura; Barnaba, Carla; Bragato, Pier Luigi

2014-05-01

Schools have a fundamental role in broadening the understanding of natural hazard and risks and in building the awareness in the community. Recent earthquakes in Italy and worldwide, have clearly demonstrated that the poor perception of seismic hazards diminishes the effectiveness of mitigation countermeasures. Since years the Seismology's department of OGS is involved in education projects and public activities to raise awareness about earthquakes. Working together with teachers we aim at developing age-appropriate curricula to improve the student's knowledge about earthquakes, seismic safety, and seismic risk reduction. Some examples of education activities we performed during the last years are here presented. We show our experience with the primary and intermediate schools where, through hands-on activities, we explain the earthquake phenomenon and its effects to kids, but we illustrate also some teaching interventions for high school students. During the past years we lectured classes, we led laboratory and field activities, and we organized summer stages for selected students. In the current year we are leading a project aimed at training high school students on seismic safety through a multidisciplinary approach that involves seismologists, engineers and experts of safety procedures. To combine the objective of dissemination of earthquake culture, also through the knowledge of the past seismicity, with that of a safety culture, we use innovative educational techniques and multimedia resources. Students and teachers, under the guidance of an expert seismologist, organize a combination of hands-on activities for understanding earthquakes in the lab through cheap tools and instrumentations At selected schools we provided the low cost seismometers of the QuakeCatcher network (http://qcn.stanford.edu) for recording earthquakes, and we trained teachers to use such instruments in the lab and to analyze recorded data. Within the same project we are going to train

Natural Time and Nowcasting Earthquakes: Are Large Global Earthquakes Temporally Clustered?

Science.gov (United States)

Luginbuhl, Molly; Rundle, John B.; Turcotte, Donald L.

2018-02-01

The objective of this paper is to analyze the temporal clustering of large global earthquakes with respect to natural time, or interevent count, as opposed to regular clock time. To do this, we use two techniques: (1) nowcasting, a new method of statistically classifying seismicity and seismic risk, and (2) time series analysis of interevent counts. We chose the sequences of M_{λ } ≥ 7.0 and M_{λ } ≥ 8.0 earthquakes from the global centroid moment tensor (CMT) catalog from 2004 to 2016 for analysis. A significant number of these earthquakes will be aftershocks of the largest events, but no satisfactory method of declustering the aftershocks in clock time is available. A major advantage of using natural time is that it eliminates the need for declustering aftershocks. The event count we utilize is the number of small earthquakes that occur between large earthquakes. The small earthquake magnitude is chosen to be as small as possible, such that the catalog is still complete based on the Gutenberg-Richter statistics. For the CMT catalog, starting in 2004, we found the completeness magnitude to be M_{σ } ≥ 5.1. For the nowcasting method, the cumulative probability distribution of these interevent counts is obtained. We quantify the distribution using the exponent, β, of the best fitting Weibull distribution; β = 1 for a random (exponential) distribution. We considered 197 earthquakes with M_{λ } ≥ 7.0 and found β = 0.83 ± 0.08. We considered 15 earthquakes with M_{λ } ≥ 8.0, but this number was considered too small to generate a meaningful distribution. For comparison, we generated synthetic catalogs of earthquakes that occur randomly with the Gutenberg-Richter frequency-magnitude statistics. We considered a synthetic catalog of 1.97 × 10^5 M_{λ } ≥ 7.0 earthquakes and found β = 0.99 ± 0.01. The random catalog converted to natural time was also random. We then generated 1.5 × 10^4 synthetic catalogs with 197 M_{λ } ≥ 7.0 in each catalog and

Criteria for waste-related risks to be below regulatory concern

International Nuclear Information System (INIS)

Trubatch, S.L.

1986-01-01

This paper describes and analyzes the criteria recently established by the US Court of Appeals for the District of Columbia Circuit for determining that a risk is de minimis, i.e., below regulatory concern (BRC), for the purpose of the Atomic Energy Act of 1954, as amended, 42 USC 2011 et seq. The court established these BRC criteria incidentally during its review of intervenors' challenge to the US Nuclear Regulatory Commission's (NRC's) issuance of an operating license for the Diablo Canyon Nuclear Power Plant. In the course of that licensing proceeding, the NRC had determined that its regulations did not require it to consider the complicating effects of earthquakes on emergency planning. Although the legal standard and its quantitation arose in the context of emergency planning, these criteria are equally applicable to waste-related risks cognizable under the Atomic Energy Act. These criteria imply that the NRC, when licensing a waste repository, need not consider the risk of a catastrophic accident having a frequency of occurrence of less than one chance in one hundred thousand per year

Earthquake Hazard for Aswan High Dam Area

Science.gov (United States)

Ismail, Awad

2016-04-01

Earthquake activity and seismic hazard analysis are important components of the seismic aspects for very essential structures such as major dams. The Aswan High Dam (AHD) created the second man-made reservoir in the world (Lake Nasser) and is constructed near urban areas pose a high-risk potential for downstream life and property. The Dam area is one of the seismically active regions in Egypt and is occupied with several cross faults, which are dominant in the east-west and north-south. Epicenters were found to cluster around active faults in the northern part of Lake and AHD location. The space-time distribution and the relation of the seismicity with the lake water level fluctuations were studied. The Aswan seismicity separates into shallow and deep seismic zones, between 0 and 14 and 14 and 30 km, respectively. These two seismic zones behave differently over time, as indicated by the seismicity rate, lateral extent, b-value, and spatial clustering. It is characterized by earthquake swarm sequences showing activation of the clustering-events over time and space. The effect of the North African drought (1982 to present) is clearly seen in the reservoir water level. As it decreased and left the most active fault segments uncovered, the shallow activity was found to be more sensitive to rapid discharging than to the filling. This study indicates that geology, topography, lineations in seismicity, offsets in the faults, changes in fault trends and focal mechanisms are closely related. No relation was found between earthquake activity and both-ground water table fluctuations and water temperatures measured in wells located around the Kalabsha area. The peak ground acceleration is estimated in the dam site based on strong ground motion simulation. This seismic hazard analyses have indicated that AHD is stable with the present seismicity. The earthquake epicenters have recently took place approximately 5 km west of the AHD structure. This suggests that AHD dam must be

An investigation into the socioeconomic aspects of two major earthquakes in Iran.

Science.gov (United States)

Amini Hosseini, Kambod; Hosseinioon, Solmaz; Pooyan, Zhila

2013-07-01

An evaluation of the socioeconomic consequences of earthquakes is an essential part of the development of risk reduction and disaster management plans. However, these variables are not normally addressed sufficiently after strong earthquakes; researchers and relevant stakeholders focus primarily on the physical damage and casualties. The importance of the socioeconomic consequences of seismic events became clearer in Iran after the Bam earthquake on 26 December 2003, as demonstrated by the formulation and approval of various laws and ordinances. This paper reviews the country's regulatory framework in the light of the socioeconomic aspects of two major and destructive earthquakes: in Manjil-Rudbar in 1990, and in Bam in 2003. The results take the form of recommendations and practical strategies for incorporating the socioeconomic dimensions of earthquakes in disaster risk management planning. The results presented here can be applied in other countries with similar conditions to those of Iran in order to improve public preparedness and risk reduction. © 2013 The Author(s). Journal compilation © Overseas Development Institute, 2013.

Topographic changes and their driving factors after 2008 Wenchuan Earthquake

Science.gov (United States)

Li, C.; Wang, M.; Xie, J.; Liu, K.

2017-12-01

The Wenchuan Ms 8.0 Earthquake caused topographic change in the stricken areas because of the formation of numerous coseismic landslides. The emergence of new landslides and debris flows and movement of loose materials under the driving force of heavy rainfall could further shape the local topography. Dynamic topographic changes in mountainous areas stricken by major earthquakes have a strong linkage to the development and occurrence of secondary disasters. However, little attention has been paid to continuously monitoring mountain environment change after such earthquakes. A digital elevation model (DEM) is the main feature of the terrain surface, in our research, we extracted DEM in 2013 and 2015 of a typical mountainous area severely impacted by the 2008 Wenchuan earthquake from the ZY-3 stereo pair images with validation by field measurement. Combined with the elevation dataset in 2002 and 2010, we quantitatively assessed elevation changes in different years and qualitatively analyzed spatiotemporal variation of the terrain and mass movement across the study area. The results show that the earthquake stricken area experienced substantial elevation changes caused by seismic forces and subsequent rainfalls. Meanwhile, deposits after the earthquake are mainly accumulated on the river-channels and mountain ridges and deep gullies which increase the risk of other geo-hazards. And the heavy rainfalls after the earthquake have become the biggest driver of elevation reduction, which overwhelmed elevation increase during the major earthquake. Our study provided a better understanding of subsequent hazards and risks faced by residents and communities stricken by major earthquakes.

Mapping individuals' earthquake preparedness in China

Directory of Open Access Journals (Sweden)

G. Wu

2018-05-01

Full Text Available Disaster preparedness is critical for reducing potential impact. This paper contributes to current knowledge of disaster preparedness using representative national sample data from China, which faces high earthquake risks in many areas of the country. The adoption of earthquake preparedness activities by the general public, including five indicators of material preparedness and five indicators of awareness preparedness, were surveyed and 3245 respondents from all 31 provinces of Mainland China participated in the survey. Linear regression models and logit regression models were used to analyze the effects of potential influencing factors. Overall, the preparedness levels are not satisfied, with a material preparation score of 3.02 (1–5, and awareness preparation score of 2.79 (1–5, nationally. Meanwhile, residents from western China, which has higher earthquake risk, have higher degrees of preparedness. The concern for disaster risk reduction (DRR and the concern for building safety and participation in public affairs are consistent positive predictors of both material and awareness preparedness. The demographic and socioeconomic variables' effects, such as gender, age, education, income, urban/rural division, and building size, vary according to different preparedness activities. Finally, the paper concludes with a discussion of the theoretical contribution and potential implementation.

Precursory diffuse carbon dioxide degassing signature related to a 5.1 magnitude earthquake in El Salvador, Central America

Science.gov (United States)

Salazar, J. M. L.; Pérez, N. M.; Hernández, P. A.; Soriano, T.; Barahona, F.; Olmos, R.; Cartagena, R.; López, D. L.; Lima, R. N.; Melián, G.; Galindo, I.; Padrón, E.; Sumino, H.; Notsu, K.

2002-12-01

Anomalous changes in the diffuse emission of carbon dioxide have been observed before some of the aftershocks of the 13 February 2001 El Salvador earthquake (magnitude 6.6). A significant increase in soil CO 2 efflux was detected 8 days before a 5.1 magnitude earthquake on 8 May 2001 25 km away from the observation site. In addition, pre- and co-seismic CO 2 efflux variations have also been observed related to the onset of a seismic swarm beneath San Vicente volcano on May 2001. Strain changes and/or fluid pressure fluctuations prior to earthquakes in the crust are hypothesized to be responsible for the observed variations in gas efflux at the surface environment of San Vicente volcano.

Assessment of risks of loose landslide deposits formed by the 2008 Wenchuan earthquake

Science.gov (United States)

Zhang, S.; Zhang, L. M.; Peng, M.; Zhang, L. L.; Zhao, H. F.; Chen, H. X.

2012-05-01

A Geographic Information System (GIS)-based quantitative risk assessment methodology was adopted to evaluate the risks of loose deposits formed by the 2008 Wenchuan earthquake along a highway near the epicenter. A total of 305 loose deposits with a total volume of 4.0 × 107 m3 has been identified. A physical model was used to determine the failure probability of these loose deposits under six rainfall scenarios, assuming the loose deposits as infinite slopes. The calculated probability of rain-induced slope failures is verified by the recorded landslides at the same site during a storm in 2010. Seventy-nine out of the 112 rain-induced loose deposit failures are predicted by the reliability analysis, with an accuracy of 71%. The results of reliability analysis and information on the consequence of these rain-induced landslides enable the estimation of the annual societal and individual risks of the loose deposits. Under the rainfall scenarios of 30 mm/12 h and 70 mm/12 h, the estimated annual societal risks reach 8.8 and 7.5, respectively, and the individual risks reach 0.05 and 0.04, respectively, which are very high compared with present risk acceptance criteria. The preliminary assessment provides a benchmark for studying the long-term risks of these loose deposits and engineering decision.

Profile and procedures for fractures among 1323 fracture patients from the 2010 Yushu earthquake, China.

Science.gov (United States)

Kang, Peng; Tang, Bihan; Liu, Yuan; Liu, Xu; Shen, Yan; Liu, Zhipeng; Yang, Hongyang; Zhang, Lulu

2016-11-01

The injuries caused by earthquakes are often complex and of various patterns. Our study included all fracture inpatients from the Yushu earthquake (1323 in total), to learn more about the incidence and distribution of fractures during earthquakes. A retrospective study of the clinical characteristics of hospitalized fracture patients after the 2010 Yushu earthquake was conducted from December 20 to 25, 2010.We reviewed medical records of hospitalized patients who had been evacuated from the Yushu earthquake area between April 14 and June 15, 2010, from 57 hospitals, and also reviewed more than 100 documents assembled from daily medical rescue and disease prevention reports submitted by the frontline rescue organizations. In total, 78.0% of fracture patients were admitted to the hospital within 3 days after the earthquake. There were 1323 patients who presented with 1539 fractures. The most common fracture occurred in the lower limbs, followed by spinal, pelvic, and shoulder-upper limb fractures. The end of the thoracic vertebra and the lumbar vertebra were the high-risk sites for vertebral fractures. A total of 38 patients became paraplegic. A 2-level spatial clustering was detected among the 193 patients presenting with 2 fractures. Analysis profiles of the injuries and clinical features of patients with earthquake-related fractures will positively impact rescue efforts and the treatment of fracture injuries caused by possible future natural disasters. We should assemble orthopedic-related medications and surgical equipment, and allocate them promptly after a major earthquake. Copyright © 2016 Elsevier Inc. All rights reserved.

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.

Dynamic Assessment of Seismic Risk (DASR) by Multi-parametric Observations: Preliminary Results of PRIME experiment within the PRE-EARTHQUAKES EU-FP7 Project

Science.gov (United States)

Tramutoli, V.; Inan, S.; Jakowski, N.; Pulinets, S. A.; Romanov, A.; Filizzola, C.; Shagimuratov, I.; Pergola, N.; Ouzounov, D. P.; Papadopoulos, G. A.; Parrot, M.; Genzano, N.; Lisi, M.; Alparlsan, E.; Wilken, V.; Tsybukia, K.; Romanov, A.; Paciello, R.; Zakharenkova, I.; Romano, G.

2012-12-01

The integration of different observations together with the refinement of data analysis methods, is generally expected to improve our present knowledge of preparatory phases of earthquakes and of their possible precursors. This is also the main goal of PRE-EARTHQUAKES (Processing Russian and European EARTH observations for earthQUAKE precursors Studies) the FP7 Project which, to this aim, committed together, different international expertise and observational capabilities, in the last 2 years. In the learning phase of the project, different parameters (e.g. thermal anomalies, total electron content, radon concentration, etc.), measured from ground and satellite systems and analyzed by using different data analysis approaches, have been studied for selected geographic areas and specific seismic events in the past. Since July 2012 the PRIME (PRE-EARTHQUAKES Real-time Integration and Monitoring Experiment) started attempting to perform, on the base of independent observations collected and integrated in real-time through the PEG (PRE-EARTHQUAKES Geo-portal), a Dynamic Assessment of Seismic Risk (DASR) on selected geographic areas of Europe (Italy-Greece-Turkey) and Asia (Kamchatka, Sakhalin, Japan). In this paper, results so far achieved as well as the potential and opportunities they open for a worldwide Earthquake Observation System (EQuOS) - as a dedicated component of GEOSS (Global Earth Observation System of Systems) - will be presented.

The wicked problem of earthquake hazard in developing countries: the example of Bangladesh

Science.gov (United States)

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

2017-12-01

Many developing nations in earthquake-prone areas confront a tough problem: how much of their limited resources to use mitigating earthquake hazards? This decision is difficult because it is unclear when an infrequent major earthquake may happen, how big it could be, and how much harm it may cause. This issue faces nations with profound immediate needs and ongoing rapid urbanization. Earthquake hazard mitigation in Bangladesh is a wicked problem. It is the world's most densely populated nation, with 160 million people in an area the size of Iowa. Complex geology and sparse data make assessing a possibly-large earthquake hazard difficult. Hence it is hard to decide how much of the limited resources available should be used for earthquake hazard mitigation, given other more immediate needs. Per capita GDP is $1200, so Bangladesh is committed to economic growth and resources are needed to address many critical challenges and hazards. In their subtropical environment, rural Bangladeshis traditionally relied on modest mud or bamboo homes. Their rapidly growing, crowded capital, Dhaka, is filled with multistory concrete buildings likely to be vulnerable to earthquakes. The risk is compounded by the potential collapse of services and accessibility after a major temblor. However, extensive construction as the population shifts from rural to urban provides opportunity for earthquake-risk reduction. While this situation seems daunting, it is not hopeless. Robust risk management is practical, even for developing nations. It involves recognizing uncertainties and developing policies that should give a reasonable outcome for a range of the possible hazard and loss scenarios. Over decades, Bangladesh has achieved a thousandfold reduction in risk from tropical cyclones by building shelters and setting up a warning system. Similar efforts are underway for earthquakes. Smart investments can be very effective, even if modest. Hence, we suggest strategies consistent with high

The Christchurch earthquake stroke incidence study.

Science.gov (United States)

Wu, Teddy Y; Cheung, Jeanette; Cole, David; Fink, John N

2014-03-01

We examined the impact of major earthquakes on acute stroke admissions by a retrospective review of stroke admissions in the 6 weeks following the 4 September 2010 and 22 February 2011 earthquakes. The control period was the corresponding 6 weeks in the previous year. In the 6 weeks following the September 2010 earthquake there were 97 acute stroke admissions, with 79 (81.4%) ischaemic infarctions. This was similar to the 2009 control period which had 104 acute stroke admissions, of whom 80 (76.9%) had ischaemic infarction. In the 6 weeks following the February 2011 earthquake, there were 71 stroke admissions, and 61 (79.2%) were ischaemic infarction. This was less than the 96 strokes (72 [75%] ischaemic infarction) in the corresponding control period. None of the comparisons were statistically significant. There was also no difference in the rate of cardioembolic infarction from atrial fibrillation between the study periods. Patients admitted during the February 2011 earthquake period were less likely to be discharged directly home when compared to the control period (31.2% versus 46.9%, p=0.036). There was no observable trend in the number of weekly stroke admissions between the 2 weeks leading to and 6 weeks following the earthquakes. Our results suggest that severe psychological stress from earthquakes did not influence the subsequent short term risk of acute stroke, but the severity of the earthquake in February 2011 and associated civil structural damages may have influenced the pattern of discharge for stroke patients. Copyright © 2013 Elsevier Ltd. All rights reserved.

Seismic experience in power and industrial facilities as it relates to small magnitude earthquakes

International Nuclear Information System (INIS)

Swan, S.W.; Horstman, N.G.

1987-01-01

The data base on the performance of power and industrial facilities in small magnitude earthquakes (M = 4.0 - 5.5) is potentially very large. In California alone many earthquakes in this magnitude range occur every year, often near industrial areas. In 1986 for example, in northern California alone, there were 76 earthquakes between Richter magnitude 4.0 and 5.5. Experience has shown that the effects of small magnitude earthquakes are seldom significant to well-engineered facilities. (The term well-engineered is here defined to include most modern industrial installations, as well as power plants and substations.) Therefore detailed investigations of small magnitude earthquakes are normally not considered worthwhile. The purpose of this paper is to review the tendency toward seismic damage of equipment installations representative of nuclear power plant safety systems. Estimates are made of the thresholds of seismic damage to certain types of equipment in terms of conventional means of measuring the damage potential of an earthquake. The objective is to define thresholds of damage that can be correlated with Richter magnitude. In this manner an earthquake magnitude might be chosen below which damage to nuclear plant safety systems is not considered credible

Assessment of earthquake-induced landslides hazard in El Salvador after the 2001 earthquakes using macroseismic analysis

Science.gov (United States)

Esposito, Eliana; Violante, Crescenzo; Giunta, Giuseppe; Ángel Hernández, Miguel

2016-04-01

Two strong earthquakes and a number of smaller aftershocks struck El Salvador in the year 2001. The January 13 2001 earthquake, Mw 7.7, occurred along the Cocos plate, 40 km off El Salvador southern coast. It resulted in about 1300 deaths and widespread damage, mainly due to massive landsliding. Two of the largest earthquake-induced landslides, Las Barioleras and Las Colinas (about 2x105 m3) produced major damage to buildings and infrastructures and 500 fatalities. A neighborhood in Santa Tecla, west of San Salvador, was destroyed. The February 13 2001 earthquake, Mw 6.5, occurred 40 km east-southeast of San Salvador. This earthquake caused over 300 fatalities and triggered several landslides over an area of 2,500 km2 mostly in poorly consolidated volcaniclastic deposits. The La Leona landslide (5-7x105 m3) caused 12 fatalities and extensive damage to the Panamerican Highway. Two very large landslides of 1.5 km3 and 12 km3 produced hazardous barrier lakes at Rio El Desague and Rio Jiboa, respectively. More than 16.000 landslides occurred throughout the country after both quakes; most of them occurred in pyroclastic deposits, with a volume less than 1x103m3. The present work aims to define the relationship between the above described earthquake intensity, size and areal distribution of induced landslides, as well as to refine the earthquake intensity in sparsely populated zones by using landslide effects. Landslides triggered by the 2001 seismic sequences provided useful indication for a realistic seismic hazard assessment, providing a basis for understanding, evaluating, and mapping the hazard and risk associated with earthquake-induced landslides.

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

International Nuclear Information System (INIS)

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

2011-06-01

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

Episodic radon changes in subsurface soil gas along active faults and possible relation to earthquakes

International Nuclear Information System (INIS)

King, C.

1980-01-01

Subsurface soil gas along active faults in central California has been continuously monitored by the Track Etch method to test whether its radon-isotope content may show any premonitory changes useful for earthquake prediction. The monitoring network was installed in May 1975 and has since been gradually expanded to consist of more than 60 stations along a 380-km section of the San Andreas fault system between Santa Rosa and Cholame. This network has recorded several episodes, each lasting several weeks to several months, during which the radon concentration increased by a factor of approximately 2 above average along some long, but limited, fault segments (approx.100 km). These episodes occurred in different seasons and do not appear to be systematically related to changes in meteorological conditions. However, they coincided reasonably well in time and space with larger local earthquakes above a threshold magnitude of about 4.0. These episodic radon changes may be caused by a changing outgassing rate in the fault zones in response to some episodic strain changes, which incidentally caused the earthquakes

Role of the Internet in Anticipating and Mitigating Earthquake Catastrophes, and the Emergence of Personal Risk Management (Invited)

Science.gov (United States)

Rundle, J. B.; Holliday, J. R.; Donnellan, A.; Graves, W.; Tiampo, K. F.; Klein, W.

2009-12-01

Risks from natural and financial catastrophes are currently managed by a combination of large public and private institutions. Public institutions usually are comprised of government agencies that conduct studies, formulate policies and guidelines, enforce regulations, and make “official” forecasts. Private institutions include insurance and reinsurance companies, and financial service companies that underwrite catastrophe (“cat”) bonds, and make private forecasts. Although decisions about allocating resources and developing solutions are made by large institutions, the costs of dealing with catastrophes generally fall for the most part on businesses and the general public. Information on potential risks is generally available to the public for some hazards but not others. For example, in the case of weather, private forecast services are provided by www.weather.com and www.wunderground.com. For earthquakes in California (only), the official forecast is the WGCEP-USGS forecast, but provided in a format that is difficult for the public to use. Other privately made forecasts are currently available, for example by the JPL QuakeSim and Russian groups, but these efforts are limited. As more of the world’s population moves increasingly into major seismic zones, new strategies are needed to allow individuals to manage their personal risk from large and damaging earthquakes. Examples include individual mitigation measures such as retrofitting, as well as microinsurance in both developing and developed countries, as well as other financial strategies. We argue that the “long tail” of the internet offers an ideal, and greatly underutilized mechanism to reach out to consumers and to provide them with the information and tools they need to confront and manage seismic hazard and risk on an individual, personalized basis. Information of this type includes not only global hazard forecasts, which are now possible, but also global risk estimation. Additionally

Limitation of the Predominant-Period Estimator for Earthquake Early Warning and the Initial Rupture of Earthquakes

Science.gov (United States)

Yamada, T.; Ide, S.

2007-12-01

Earthquake early warning is an important and challenging issue for the reduction of the seismic damage, especially for the mitigation of human suffering. One of the most important problems in earthquake early warning systems is how immediately we can estimate the final size of an earthquake after we observe the ground motion. It is relevant to the problem whether the initial rupture of an earthquake has some information associated with its final size. Nakamura (1988) developed the Urgent Earthquake Detection and Alarm System (UrEDAS). It calculates the predominant period of the P wave (τp) and estimates the magnitude of an earthquake immediately after the P wave arrival from the value of τpmax, or the maximum value of τp. The similar approach has been adapted by other earthquake alarm systems (e.g., Allen and Kanamori (2003)). To investigate the characteristic of the parameter τp and the effect of the length of the time window (TW) in the τpmax calculation, we analyze the high-frequency recordings of earthquakes at very close distances in the Mponeng mine in South Africa. We find that values of τpmax have upper and lower limits. For larger earthquakes whose source durations are longer than TW, the values of τpmax have an upper limit which depends on TW. On the other hand, the values for smaller earthquakes have a lower limit which is proportional to the sampling interval. For intermediate earthquakes, the values of τpmax are close to their typical source durations. These two limits and the slope for intermediate earthquakes yield an artificial final size dependence of τpmax in a wide size range. The parameter τpmax is useful for detecting large earthquakes and broadcasting earthquake early warnings. However, its dependence on the final size of earthquakes does not suggest that the earthquake rupture is deterministic. This is because τpmax does not always have a direct relation to the physical quantities of an earthquake.

Preliminary report on Petatlan, Mexico: earthquake of 14 March 1979

Energy Technology Data Exchange (ETDEWEB)

1979-01-01

A major earthquake, M/sub s/ = 7.6, occurred off the southern coast of Mexico near the town of Petatlan on 14 March 1979. The earthquake ruptured a 50-km-long section of the Middle American subduction zone, a seismic gap last ruptured by a major earthquake (M/sub s/ = 7.5) in 1943. Since adjacent gaps of approximately the same size have not had a large earthquake since 1911, and one of these suffered three major earthquakes in four years (1907, 1909, 1911), recurrence times for large events here are highly variable. Thus, this general area remains one of high seismic risk, and provides a focus for investigation of segmentation in the subduction processes. 2 figures.

Ionospheric precursors to large earthquakes: A case study of the 2011 Japanese Tohoku Earthquake

Science.gov (United States)

Carter, B. A.; Kellerman, A. C.; Kane, T. A.; Dyson, P. L.; Norman, R.; Zhang, K.

2013-09-01

Researchers have reported ionospheric electron distribution abnormalities, such as electron density enhancements and/or depletions, that they claimed were related to forthcoming earthquakes. In this study, the Tohoku earthquake is examined using ionosonde data to establish whether any otherwise unexplained ionospheric anomalies were detected in the days and hours prior to the event. As the choices for the ionospheric baseline are generally different between previous works, three separate baselines for the peak plasma frequency of the F2 layer, foF2, are employed here; the running 30-day median (commonly used in other works), the International Reference Ionosphere (IRI) model and the Thermosphere Ionosphere Electrodynamic General Circulation Model (TIE-GCM). It is demonstrated that the classification of an ionospheric perturbation is heavily reliant on the baseline used, with the 30-day median, the IRI and the TIE-GCM generally underestimating, approximately describing and overestimating the measured foF2, respectively, in the 1-month period leading up to the earthquake. A detailed analysis of the ionospheric variability in the 3 days before the earthquake is then undertaken, where a simultaneous increase in foF2 and the Es layer peak plasma frequency, foEs, relative to the 30-day median was observed within 1 h before the earthquake. A statistical search for similar simultaneous foF2 and foEs increases in 6 years of data revealed that this feature has been observed on many other occasions without related seismic activity. Therefore, it is concluded that one cannot confidently use this type of ionospheric perturbation to predict an impending earthquake. It is suggested that in order to achieve significant progress in our understanding of seismo-ionospheric coupling, better account must be taken of other known sources of ionospheric variability in addition to solar and geomagnetic activity, such as the thermospheric coupling.

Earthquakes

Science.gov (United States)

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

Structural Risk Assessment and Mitigation for Low- to Mid-Rise Residential Buildings in China

Directory of Open Access Journals (Sweden)

Kasim A. Korkmaz

2017-07-01

Full Text Available China has experienced major earthquakes recently. The 2014 Ludian earthquake struck Ludian County, Yunnan, (Mw = 6.1 on 3 August, 2014. On April 20th 2013, Ya’an earthquake (Mw = 6.9, on April 14th 2010, Qinghai earthquake (Mw = 7.1, on July 9th 2009, Yunnan earthquake (Mw = 6.0, and on May 12th 2008, Sichuan earthquake (Mw = 7.9 struck China. Among these disasters, the most devastating, the Sichuan earthquake, resulted in the collapse of 5 million buildings and damage to more than 21 million. Human loss was also high with over 60,000 people dead, 360,000 injured, and more than 14 million people displaced. South-west China lies in an area that is prone to earthquakes. In 1970, a magnitude 7.7 earthquake in Yunnan with 15,000 lost. This study presents a detailed risk assessment for a structural risk assessment and mitigation for low- to mid-rise residential buildings for China. The risk assessment, through seismic hazard assessment approaches, evaluates the impact of the disasters for integrated structural health monitoring. Among the results of the investigation, relations and links between safety and risk are defined.

Relationship of heat and cold to earthquakes

Energy Technology Data Exchange (ETDEWEB)

Chen, Y.

1980-06-26

An analysis of 54 earthquakes of magnitude 7 and above, including 13 of magnitude 8 and above, between 780 BC and the present, shows that the vast majority of them fell in the four major cool periods during this time span, or on the boundaries of these periods. Between 1800 and 1876, four periods of earthquake activity in China can be recognized, and these tend to correspond to relatively cold periods over that time span. An analysis of earthquakes of magnitude 6 or above over the period 1951 to 1965 gives the following results: earthquakes in north and southwest China tended to occur when the preceding year had an above-average annual temperature and winter temperature; in the northeast they tended to occur in a year after a year with an above-average winter temperature; in the northwest there was also a connection with a preceding warm winter, but to a less pronounced degree. The few earthquakes in South China seemed to follow cold winters. Both the Tangshan and Yongshan Pass earthquakes were preceded by unusually warm years and relatively high winter temperatures.

Studies of the subsurface effects of earthquakes

International Nuclear Information System (INIS)

Marine, I.W.

1980-01-01

As part of the National Terminal Waste Storage Program, the Savannah River Laboratory is conducting a series of studies on the subsurface effects of earthquakes. This report summarizes three subcontracted studies. (1) Earthquake damage to underground facilities: the purpose of this study was to document damage and nondamage caused by earthquakes to tunnels and shallow underground openings; to mines and other deep openings; and to wells, shafts, and other vertical facilities. (2) Earthquake related displacement fields near underground facilities: the study included an analysis of block motion, an analysis of the dependence of displacement on the orientation and distance of joints from the earthquake source, and displacement related to distance and depth near a causative fault as a result of various shapes, depths, and senses of movement on the causative fault. (3) Numerical simulation of earthquake effects on tunnels for generic nuclear waste repositories: the objective of this study was to use numerical modeling to determine under what conditions seismic waves might cause instability of an underground opening or create fracturing that would increase the permeability of the rock mass

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

EARTHQUAKE TRIGGERING AND SPATIAL-TEMPORAL RELATIONS IN THE VICINITY OF YUCCA MOUNTAIN, NEVADA

Energy Technology Data Exchange (ETDEWEB)

na

2001-02-08

It is well accepted that the 1992 M 5.6 Little Skull Mountain earthquake, the largest historical event to have occurred within 25 km of Yucca Mountain, Nevada, was triggered by the M 7.2 Landers earthquake that occurred the day before. On the premise that earthquakes can be triggered by applied stresses, we have examined the earthquake catalog from the Southern Great Basin Digital Seismic Network (SGBDSN) for other evidence of triggering by external and internal stresses. This catalog now comprises over 12,000 events, encompassing five years of consistent monitoring, and has a low threshold of completeness, varying from M 0 in the center of the network to M 1 at the fringes. We examined the SGBDSN catalog response to external stresses such as large signals propagating from teleseismic and regional earthquakes, microseismic storms, and earth tides. Results are generally negative. We also examined the interplay of earthquakes within the SGBDSN. The number of ''foreshocks'', as judged by most criteria, is significantly higher than the background seismicity rate. In order to establish this, we first removed aftershocks from the catalog with widely used methodology. The existence of SGBDSN foreshocks is supported by comparing actual statistics to those of a simulated catalog with uniform-distributed locations and Poisson-distributed times of occurrence. The probabilities of a given SGBDSN earthquake being followed by one having a higher magnitude within a short time frame and within a close distance are at least as high as those found with regional catalogs. These catalogs have completeness thresholds two to three units higher in magnitude than the SGBDSN catalog used here. The largest earthquake in the SGBDSN catalog, the M 4.7 event in Frenchman Flat on 01/27/1999, was preceded by a definite foreshock sequence. The largest event within 75 km of Yucca Mountain in historical time, the M 5.7 Scotty's Junction event of 08/01/1999, was also

EARTHQUAKE TRIGGERING AND SPATIAL-TEMPORAL RELATIONS IN THE VICINITY OF YUCCA MOUNTAIN, NEVADA

International Nuclear Information System (INIS)

2001-01-01

It is well accepted that the 1992 M 5.6 Little Skull Mountain earthquake, the largest historical event to have occurred within 25 km of Yucca Mountain, Nevada, was triggered by the M 7.2 Landers earthquake that occurred the day before. On the premise that earthquakes can be triggered by applied stresses, we have examined the earthquake catalog from the Southern Great Basin Digital Seismic Network (SGBDSN) for other evidence of triggering by external and internal stresses. This catalog now comprises over 12,000 events, encompassing five years of consistent monitoring, and has a low threshold of completeness, varying from M 0 in the center of the network to M 1 at the fringes. We examined the SGBDSN catalog response to external stresses such as large signals propagating from teleseismic and regional earthquakes, microseismic storms, and earth tides. Results are generally negative. We also examined the interplay of earthquakes within the SGBDSN. The number of ''foreshocks'', as judged by most criteria, is significantly higher than the background seismicity rate. In order to establish this, we first removed aftershocks from the catalog with widely used methodology. The existence of SGBDSN foreshocks is supported by comparing actual statistics to those of a simulated catalog with uniform-distributed locations and Poisson-distributed times of occurrence. The probabilities of a given SGBDSN earthquake being followed by one having a higher magnitude within a short time frame and within a close distance are at least as high as those found with regional catalogs. These catalogs have completeness thresholds two to three units higher in magnitude than the SGBDSN catalog used here. The largest earthquake in the SGBDSN catalog, the M 4.7 event in Frenchman Flat on 01/27/1999, was preceded by a definite foreshock sequence. The largest event within 75 km of Yucca Mountain in historical time, the M 5.7 Scotty's Junction event of 08/01/1999, was also preceded by foreshocks. The

Large earthquakes and creeping faults

Science.gov (United States)

Harris, Ruth A.

2017-01-01

Faults are ubiquitous throughout the Earth's crust. The majority are silent for decades to centuries, until they suddenly rupture and produce earthquakes. With a focus on shallow continental active-tectonic regions, this paper reviews a subset of faults that have a different behavior. These unusual faults slowly creep for long periods of time and produce many small earthquakes. The presence of fault creep and the related microseismicity helps illuminate faults that might not otherwise be located in fine detail, but there is also the question of how creeping faults contribute to seismic hazard. It appears that well-recorded creeping fault earthquakes of up to magnitude 6.6 that have occurred in shallow continental regions produce similar fault-surface rupture areas and similar peak ground shaking as their locked fault counterparts of the same earthquake magnitude. The behavior of much larger earthquakes on shallow creeping continental faults is less well known, because there is a dearth of comprehensive observations. Computational simulations provide an opportunity to fill the gaps in our understanding, particularly of the dynamic processes that occur during large earthquake rupture and arrest.

The 2011 Tohoku-oki Earthquake related to a large velocity gradient within the Pacific plate

Science.gov (United States)

Matsubara, Makoto; Obara, Kazushige

2015-04-01

rays from the hypocenter around the coseismic region of the Tohoku-oki earthquake take off downward and pass through the Pacific plate. The landward low-V zone with a large anomaly corresponds to the western edge of the coseismic slip zone of the 2011 Tohoku-oki earthquake. The initial break point (hypocenter) is associated with the edge of a slightly low-V and low-Vp/Vs zone corresponding to the boundary of the low- and high-V zone. The trenchward low-V and low-Vp/Vs zone extending southwestward from the hypocenter may indicate the existence of a subducted seamount. The high-V zone and low-Vp/Vs zone might have accumulated the strain and resulted in the huge coseismic slip zone of the 2011 Tohoku earthquake. The low-V and low-Vp/Vs zone is a slight fluctuation within the high-V zone and might have acted as the initial break point of the 2011 Tohoku earthquake. Reference Matsubara, M. and K. Obara (2011) The 2011 Off the Pacific Coast of Tohoku earthquake related to a strong velocity gradient with the Pacific plate, Earth Planets Space, 63, 663-667. Okada, Y., K. Kasahara, S. Hori, K. Obara, S. Sekiguchi, H. Fujiwara, and A. Yamamoto (2004) Recent progress of seismic observation networks in Japan-Hi-net, F-net, K-NET and KiK-net, Research News Earth Planets Space, 56, xv-xxviii.

A minimalist model of characteristic earthquakes

DEFF Research Database (Denmark)

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

2002-01-01

In a spirit akin to the sandpile model of self- organized criticality, we present a simple statistical model of the cellular-automaton type which simulates the role of an asperity in the dynamics of a one-dimensional fault. This model produces an earthquake spectrum similar to the characteristic-earthquake...... behaviour of some seismic faults. This model, that has no parameter, is amenable to an algebraic description as a Markov Chain. This possibility illuminates some important results, obtained by Monte Carlo simulations, such as the earthquake size-frequency relation and the recurrence time...... of the characteristic earthquake....

The escaping "pneuma" - gas of ancient earthquake concepts in relation to animal, atmospheric and thermal precursors

Science.gov (United States)

Helmut, Tributsch

2013-04-01

The escaping "pneuma" - gas of ancient earthquake concepts in relation to animal, atmospheric and thermal precursors Helmut Tributsch Present affiliation: Carinthian University for Applied Sciences, Bio-mimetics program, Europastrasse 4, 9524 Villach, Austria, helmut.tributsch@alice.it Retired from: Free University Berlin, Institute for physical and theoretical chemistry, Takustr. 3, 14195 Berlin, Germany. For two thousand years ancient European and medieval (including islamic) natural philosophers have considered a dry, warm gas, the "pneuma" ( breath, exhalation), escaping from the earth, as precursor and trigger of earthquakes. Also in China an escaping gas or breath (the qi) was considered the cause of earthquake, first in a document from 780 BC. We know today that escaping gas is not causing earthquakes. But it may be that natural phenomena that supported such a pneuma-concept have again and again been observed. The unpolluted environment and the largely absence of distracting artificial stimuli may have allowed the recognition of distinct earthquake precursors, such as described by ancient observers: (1) the sun becomes veiled and has a dim appearance, turns reddish or dark (2) a narrow long stretched cloud becomes visible, like a line drawn by a ruler, (3) earthquakes preceded by a thin streak of cloud stretching over a wide space. (4) earthquakes in the morning sometimes preceded by a still and a strong frost, (5) a surf - line of the air sea is forming (near the horizon). The described phenomena may be interpreted as a kind of smog forming above the ground prior to an earthquake, a smog exhaled from the ground, which is triggering water condensation, releasing latent heat, changing visibility, temperature, heat conduction and radiation properties. This could perfectly match the phenomenon, which is at the origin of satellite monitored temperature anomalies preceding earthquakes. Based on a few examples it will be shown that the time window of temperature

Earthquakes and nuclear waste: A lesson in media relations

International Nuclear Information System (INIS)

Patrick, S.M.

1993-01-01

The Little Skull Mountain earthquake on June 29, 1992 marked the beginning of a challenging period for the US DOE's Yucca Mountain Site Characterization Project's (YMP's) Public Affairs department. We needed to relay complicated and difficult to understand scientific principals in an easily understandable fashion to local and national media who were hungry for detailed information. Volumes of quickly accumulating data was swiftly sorted, interpreted, and placed in context with other data in order to be properly presented. The main difficulty in this situation was attempting to assure that the information presented led to an intellectual and not emotional analysis of the earthquake. This paper will discuss some of the processes undertaken to meet both the needs of local media as well as our own needs

Proactive vs. reactive learning on buildings response and earthquake risks, in schools of Romania

Directory of Open Access Journals (Sweden)

Daniela DOBRE

2015-07-01

Full Text Available During the last 20 years, many specific activities of earthquake education and preparedness were initiated and supported in Romania by drafting materials for citizens, students, professors etc. (Georgescu et al., 2004, 2006. The education, training and information on earthquake disaster potential are important factors to mitigate the earthquake effects. Such activities, however, need time to be developed and may take different forms of presentation in order to capture the attention, to increase interest, to develop skills and attitudes in order to induce a proper behavior towards safety preparedness. It shall also be based on the accumulation of concerns and knowledge, which are, in principle, a consequence of the motivation, but which depend on the methods applied and actions taken for efficient earthquake preparedness, assessed and updated following actual earthquakes (Masuda, Midorikawa, Miki and Ohmachi, 1988. We are now at a crossroad and the proactive attitude and behavior (anticipative and participative needs to be extended in learning, within institutional framework, but correlated with the usual targets of schools and teenagers proactive issue (ROEDUSEIS-NET; Page and Page, 2003, by encouraging students in activities closer to earthquake engineering.

Recent Mega-Thrust Tsunamigenic Earthquakes and PTHA

Science.gov (United States)

Lorito, S.

2013-05-01

The occurrence of several mega-thrust tsunamigenic earthquakes in the last decade, including but not limited to the 2004 Sumatra-Andaman, the 2010 Maule, and 2011 Tohoku earthquakes, has been a dramatic reminder of the limitations in our capability of assessing earthquake and tsunami hazard and risk. However, the increasingly high-quality geophysical observational networks allowed the retrieval of most accurate than ever models of the rupture process of mega-thrust earthquakes, thus paving the way for future improved hazard assessments. Probabilistic Tsunami Hazard Analysis (PTHA) methodology, in particular, is less mature than its seismic counterpart, PSHA. Worldwide recent research efforts of the tsunami science community allowed to start filling this gap, and to define some best practices that are being progressively employed in PTHA for different regions and coasts at threat. In the first part of my talk, I will briefly review some rupture models of recent mega-thrust earthquakes, and highlight some of their surprising features that likely result in bigger error bars associated to PTHA results. More specifically, recent events of unexpected size at a given location, and with unexpected rupture process features, posed first-order open questions which prevent the definition of an heterogeneous rupture probability along a subduction zone, despite of several recent promising results on the subduction zone seismic cycle. In the second part of the talk, I will dig a bit more into a specific ongoing effort for improving PTHA methods, in particular as regards epistemic and aleatory uncertainties determination, and the computational PTHA feasibility when considering the full assumed source variability. Only logic trees are usually explicated in PTHA studies, accounting for different possible assumptions on the source zone properties and behavior. The selection of the earthquakes to be actually modelled is then in general made on a qualitative basis or remains implicit

The Value, Protocols, and Scientific Ethics of Earthquake Forecasting

Science.gov (United States)

Jordan, Thomas H.

2013-04-01

Earthquakes are different from other common natural hazards because precursory signals diagnostic of the magnitude, location, and time of impending seismic events have not yet been found. Consequently, the short-term, localized prediction of large earthquakes at high probabilities with low error rates (false alarms and failures-to-predict) is not yet feasible. An alternative is short-term probabilistic forecasting based on empirical statistical models of seismic clustering. During periods of high seismic activity, short-term earthquake forecasts can attain prospective probability gains up to 1000 relative to long-term forecasts. The value of such information is by no means clear, however, because even with hundredfold increases, the probabilities of large earthquakes typically remain small, rarely exceeding a few percent over forecasting intervals of days or weeks. Civil protection agencies have been understandably cautious in implementing operational forecasting protocols in this sort of "low-probability environment." This paper will explore the complex interrelations among the valuation of low-probability earthquake forecasting, which must account for social intangibles; the protocols of operational forecasting, which must factor in large uncertainties; and the ethics that guide scientists as participants in the forecasting process, who must honor scientific principles without doing harm. Earthquake forecasts possess no intrinsic societal value; rather, they acquire value through their ability to influence decisions made by users seeking to mitigate seismic risk and improve community resilience to earthquake disasters. According to the recommendations of the International Commission on Earthquake Forecasting (www.annalsofgeophysics.eu/index.php/annals/article/view/5350), operational forecasting systems should appropriately separate the hazard-estimation role of scientists from the decision-making role of civil protection authorities and individuals. They should

The Role of Knowledge in the prevention of natural hazards and related risks.

Directory of Open Access Journals (Sweden)

Enrico Miccadei

2014-02-01

Full Text Available Human activities, especially over the last two centuries, have had a huge impact on the environment and the landscape. Mankind is able to control and induce landscape changes but is subject to natural processes and hazards due to severe and extreme events (particularly earthquakes but also landslides and flooding and related risks. Risks are the result of hazards, exposed elements and vulnerability and they are consequently not only an expression of the natural environment, but also related to human interaction with nature. Risks need to be addressed regularly by means of a high level of knowledge in order to provide most up­to­date information for any decision which needs to be taken by any party involved. A high level of knowledge concerning natural hazards and related risks stems from the geological and geomorphological history and from the historical records of the natural processes and grows with multi­scale, multi­temporal and multidisciplinary studies and investigations, which include land management, economic and social issues. A strong effort has to be made in this way to improve risk assessment and the enforcement of existing laws and ­ if necessary ­ new laws, really stem from recent disasters. This will help to achieve improved and effective land management, based on an interdisciplinary approach in which expert geologists and land managers will play a role, because of the importance of natural processes in inducing risks.

How fault geometry controls earthquake magnitude

Science.gov (United States)

Bletery, Q.; Thomas, A.; Karlstrom, L.; Rempel, A. W.; Sladen, A.; De Barros, L.

2016-12-01

Recent large megathrust earthquakes, such as the Mw9.3 Sumatra-Andaman earthquake in 2004 and the Mw9.0 Tohoku-Oki earthquake in 2011, astonished the scientific community. The first event occurred in a relatively low-convergence-rate subduction zone where events of its size were unexpected. The second event involved 60 m of shallow slip in a region thought to be aseismicaly creeping and hence incapable of hosting very large magnitude earthquakes. These earthquakes highlight gaps in our understanding of mega-earthquake rupture processes and the factors controlling their global distribution. Here we show that gradients in dip angle exert a primary control on mega-earthquake occurrence. We calculate the curvature along the major subduction zones of the world and show that past mega-earthquakes occurred on flat (low-curvature) interfaces. A simplified analytic model demonstrates that shear strength heterogeneity increases with curvature. Stress loading on flat megathrusts is more homogeneous and hence more likely to be released simultaneously over large areas than on highly-curved faults. Therefore, the absence of asperities on large faults might counter-intuitively be a source of higher hazard.

Radon anomalies prior to earthquakes (2). Atmospheric radon anomaly observed before the Hyogoken-Nanbu earthquake

International Nuclear Information System (INIS)

Ishikawa, Tetsuo; Tokonami, Shinji; Yasuoka, Yumi; Shinogi, Masaki; Nagahama, Hiroyuki; Omori, Yasutaka; Kawada, Yusuke

2008-01-01

Before the 1995 Hyogoken-Nanbu earthquake, various geochemical precursors were observed in the aftershock area: chloride ion concentration, groundwater discharge rate, groundwater radon concentration and so on. Kobe Pharmaceutical University (KPU) is located about 25 km northeast from the epicenter and within the aftershock area. Atmospheric radon concentration had been continuously measured from 1984 at KPU, using a flow-type ionization chamber. The radon concentration data were analyzed using the smoothed residual values which represent the daily minimum of radon concentration with the exclusion of normalized seasonal variation. The radon concentration (smoothed residual values) demonstrated an upward trend about two months before the Hyogoken-Nanbu earthquake. The trend can be well fitted to a log-periodic model related to earthquake fault dynamics. As a result of model fitting, a critical point was calculated to be between 13 and 27 January 1995, which was in good agreement with the occurrence date of earthquake (17 January 1995). The mechanism of radon anomaly before earthquakes is not fully understood. However, it might be possible to detect atmospheric radon anomaly as a precursor before a large earthquake, if (1) the measurement is conducted near the earthquake fault, (2) the monitoring station is located on granite (radon-rich) areas, and (3) the measurement is conducted for more than several years before the earthquake to obtain background data. (author)

Disturbances in equilibrium function after major earthquake.

Science.gov (United States)

Honma, Motoyasu; Endo, Nobutaka; Osada, Yoshihisa; Kim, Yoshiharu; Kuriyama, Kenichi

2012-01-01

Major earthquakes were followed by a large number of aftershocks and significant outbreaks of dizziness occurred over a large area. However it is unclear why major earthquake causes dizziness. We conducted an intergroup trial on equilibrium dysfunction and psychological states associated with equilibrium dysfunction in individuals exposed to repetitive aftershocks versus those who were rarely exposed. Greater equilibrium dysfunction was observed in the aftershock-exposed group under conditions without visual compensation. Equilibrium dysfunction in the aftershock-exposed group appears to have arisen from disturbance of the inner ear, as well as individual vulnerability to state anxiety enhanced by repetitive exposure to aftershocks. We indicate potential effects of autonomic stress on equilibrium function after major earthquake. Our findings may contribute to risk management of psychological and physical health after major earthquakes with aftershocks, and allow development of a new empirical approach to disaster care after such events.

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

Science.gov (United States)

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.

Earthquake damage to underground facilities

International Nuclear Information System (INIS)

Pratt, H.R.; Stephenson, D.E.; Zandt, G.; Bouchon, M.; Hustrulid, W.A.

1980-01-01

In order to assess the seismic risk for an underground facility, a data base was established and analyzed to evaluate the potential for seismic disturbance. Substantial damage to underground facilities is usually the result of displacements primarily along pre-existing faults and fractures, or at the surface entrance to these facilities. Evidence of this comes from both earthquakes and large explosions. Therefore, the displacement due to earthquakes as a function of depth is important in the evaluation of the hazard to underground facilities. To evaluate potential displacements due to seismic effects of block motions along pre-existing or induced fractures, the displacement fields surrounding two types of faults were investigated. Analytical models were used to determine relative displacements of shafts and near-surface displacement of large rock masses. Numerical methods were used to determine the displacement fields associated with pure strike-slip and vertical normal faults. Results are presented as displacements for various fault lengths as a function of depth and distance. This provides input to determine potential displacements in terms of depth and distance for underground facilities, important for assessing potential sites and design parameters

Prevalence and psychosocial risk factors of PTSD: 18 months after Kashmir earthquake in Pakistan.

Science.gov (United States)

Naeem, Farooq; Ayub, Muhammad; Masood, Khadija; Gul, Huma; Khalid, Mahwish; Farrukh, Ammara; Shaheen, Aisha; Waheed, Waquas; Chaudhry, Haroon Rasheed

2011-04-01

On average in a year 939 earthquakes of a magnitude between 5 and 8 on the Richter scale occur around the world. In earthquakes developing countries are prone to large-scale destruction because of poor structural quality of buildings, and preparedness for earthquakes. On 8th October 2005, a major earthquake hit the remote and mountainous region of northern Pakistan and Kashmir. We wanted to find out the rate of PTSD in a randomly selected sample of participants living in earthquake area and the correlates of the PTSD. The study was conducted 18 months after the earthquake. We selected a sample of men and women living in the houses and tents for interviews. Using well established instruments for PTSD and general psychiatric morbidity we gathered information from over 1200 people in face to face interviews. We gathered information about trauma exposure and loss as well. 55.2% women and 33.4% men suffered from PTSD. Living in a joint family was protective against the symptoms of PTSD. Dose of exposure to trauma was associated with the symptoms of PTSD. Living in a tent was associated with general psychiatric morbidity but not with PTSD. We used questionnaire instead of interviews to detect the symptoms of psychiatric disorders. The symptoms of PTSD are common 18 months after the earthquake and they are specifically associated with the dose of trauma exposure. This may have implications for rehabilitation of this population. Copyright © 2010 Elsevier B.V. All rights reserved.

The 2010 Chile Earthquake: Rapid Assessments of Tsunami

OpenAIRE

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

2010-01-01

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

Seismicity and seismic hazard in Sabah, East Malaysia from earthquake and geodetic data

Science.gov (United States)

Gilligan, A.; Rawlinson, N.; Tongkul, F.; Stephenson, R.

2017-12-01

While the levels of seismicity are low in most of Malaysia, the state of Sabah in northern Borneo has moderate levels of seismicity. Notable earthquakes in the region include the 1976 M6.2 Lahad Datu earthquake and the 2015 M6 Ranau earthquake. The recent Ranau earthquake resulted in the deaths of 18 people on Mt Kinabalu, an estimated 100 million RM ( US$23 million) damage to buildings, roads, and infrastructure from shaking, and flooding, reduced water quality, and damage to farms from landslides. Over the last 40 years the population of Sabah has increased to over four times what it was in 1976, yet seismic hazard in Sabah remains poorly understood. Using seismic and geodetic data we hope to better quantify the hazards posed by earthquakes in Sabah, and thus help to minimize risk. In order to do this we need to know about the locations of earthquakes, types of earthquakes that occur, and faults that are generating them. We use data from 15 MetMalaysia seismic stations currently operating in Sabah to develop a region-specific velocity model from receiver functions and a pre-existing surface wave model. We use this new velocity model to (re)locate earthquakes that occurred in Sabah from 2005-2016, including a large number of aftershocks from the 2015 Ranau earthquake. We use a probabilistic nonlinear earthquake location program to locate the earthquakes and then refine their relative locations using a double difference method. The recorded waveforms are further used to obtain moment tensor solutions for these earthquakes. Earthquake locations and moment tensor solutions are then compared with the locations of faults throughout Sabah. Faults are identified from high-resolution IFSAR images and subsequent fieldwork, with a particular focus on the Lahad Datau and Ranau areas. Used together, these seismic and geodetic data can help us to develop a new seismic hazard model for Sabah, as well as aiding in the delivery of outreach activities regarding seismic hazard

Simplified design and evaluation of liquid storage tanks relative to earthquake loading

Energy Technology Data Exchange (ETDEWEB)

Poole, A.B.

1994-06-01

A summary of earthquake-induced damage in liquid storage tanks is provided. The general analysis steps for dynamic response of fluid-filled tanks subject to horizontal ground excitation are discussed. This work will provide major attention to the understanding of observed tank-failure modes. These modes are quite diverse in nature, but many of the commonly appearing patterns are believed to be shell buckling. A generalized and simple-to-apply shell loading will be developed using Fluegge shell theory. The input to this simplified analysis will be horizontal ground acceleration and tank shell form parameters. A dimensionless parameter will be developed and used in predictions of buckling resulting from earthquake-imposed loads. This prediction method will be applied to various tank designs that have failed during major earthquakes and during shaker table tests. Tanks that have not failed will also be reviewed. A simplified approach will be discussed for early design and evaluation of tank shell parameters and materials to provide a high confidence of low probability of failure during earthquakes.

Earthquake potential in California-Nevada implied by correlation of strain rate and seismicity

Science.gov (United States)

Zeng, Yuehua; Petersen, Mark D.; Shen, Zheng-Kang

2018-01-01

Rock mechanics studies and dynamic earthquake simulations show that patterns of seismicity evolve with time through (1) accumulation phase, (2) localization phase, and (3) rupture phase. We observe a similar pattern of changes in seismicity during the past century across California and Nevada. To quantify these changes, we correlate GPS strain rates with seismicity. Earthquakes of M > 6.5 are collocated with regions of highest strain rates. By contrast, smaller magnitude earthquakes of M ≥ 4 show clear spatiotemporal changes. From 1933 to the late 1980s, earthquakes of M ≥ 4 were more diffused and broadly distributed in both high and low strain rate regions (accumulation phase). From the late 1980s to 2016, earthquakes were more concentrated within the high strain rate areas focused on the major fault strands (localization phase). In the same time period, the rate of M > 6.5 events also increased significantly in the high strain rate areas. The strong correlation between current strain rate and the later period of seismicity indicates that seismicity is closely related to the strain rate. The spatial patterns suggest that before the late 1980s, the strain rate field was also broadly distributed because of the stress shadows from previous large earthquakes. As the deformation field evolved out of the shadow in the late 1980s, strain has refocused on the major fault systems and we are entering a period of increased risk for large earthquakes in California.

Multi-Sensor Observations of Earthquake Related Atmospheric Signals over Major Geohazard Validation Sites

Science.gov (United States)

Ouzounov, D.; Pulinets, S.; Davindenko, D.; Hattori, K.; Kafatos, M.; Taylor, P.

2012-01-01

We are conducting a scientific validation study involving multi-sensor observations in our investigation of phenomena preceding major earthquakes. Our approach is based on a systematic analysis of several atmospheric and environmental parameters, which we found, are associated with the earthquakes, namely: thermal infrared radiation, outgoing long-wavelength radiation, ionospheric electron density, and atmospheric temperature and humidity. For first time we applied this approach to selected GEOSS sites prone to earthquakes or volcanoes. This provides a new opportunity to cross validate our results with the dense networks of in-situ and space measurements. We investigated two different seismic aspects, first the sites with recent large earthquakes, viz.- Tohoku-oki (M9, 2011, Japan) and Emilia region (M5.9, 2012,N. Italy). Our retrospective analysis of satellite data has shown the presence of anomalies in the atmosphere. Second, we did a retrospective analysis to check the re-occurrence of similar anomalous behavior in atmosphere/ionosphere over three regions with distinct geological settings and high seismicity: Taiwan, Japan and Kamchatka, which include 40 major earthquakes (M>5.9) for the period of 2005-2009. We found anomalous behavior before all of these events with no false negatives; false positives were less then 10%. Our initial results suggest that multi-instrument space-borne and ground observations show a systematic appearance of atmospheric anomalies near the epicentral area that could be explained by a coupling between the observed physical parameters and earthquake preparation processes.

Deterministic earthquake scenarios for the city of Sofia

CERN Document Server

Slavov, S I; Panza, G F; Paskaleva, I; Vaccari, P

2002-01-01

The city of Sofia is exposed to a high seismic risk. Macroseismic intensities in the range of VIII-X (MSK) can be expected in the city. The earthquakes, that can influence the hazard at Sofia, originate either beneath the city or are caused by seismic sources located within a radius of 40km. The city of Sofia is also prone to the remote Vrancea seismic zone in Romania, and particularly vulnerable are the long - period elements of the built environment. The high seismic risk and the lack of instrumental recordings of the regional seismicity makes the use of appropriate credible earthquake scenarios and ground motion modelling approaches for defining the seismic input for the city of Sofia necessary. Complete synthetic seismic signals, due to several earthquake scenarios, were computed along chosen geological profiles crossing the city, applying a hybrid technique, based on the modal summation technique and finite differences. The modelling takes into account simultaneously the geotechnical properties of the si...

Tidal controls on earthquake size-frequency statistics

Science.gov (United States)

Ide, S.; Yabe, S.; Tanaka, Y.

2016-12-01

The possibility that tidal stresses can trigger earthquakes is a long-standing issue in seismology. Except in some special cases, a causal relationship between seismicity and the phase of tidal stress has been rejected on the basis of studies using many small events. However, recently discovered deep tectonic tremors are highly sensitive to tidal stress levels, with the relationship being governed by a nonlinear law according to which the tremor rate increases exponentially with increasing stress; thus, slow deformation (and the probability of earthquakes) may be enhanced during periods of large tidal stress. Here, we show the influence of tidal stress on seismicity by calculating histories of tidal shear stress during the 2-week period before earthquakes. Very large earthquakes tend to occur near the time of maximum tidal stress, but this tendency is not obvious for small earthquakes. Rather, we found that tidal stress controls the earthquake size-frequency statistics; i.e., the fraction of large events increases (i.e. the b-value of the Gutenberg-Richter relation decreases) as the tidal shear stress increases. This correlation is apparent in data from the global catalog and in relatively homogeneous regional catalogues of earthquakes in Japan. The relationship is also reasonable, considering the well-known relationship between stress and the b-value. Our findings indicate that the probability of a tiny rock failure expanding to a gigantic rupture increases with increasing tidal stress levels. This finding has clear implications for probabilistic earthquake forecasting.

Can mine tremors be predicted? Observational studies of earthquake nucleation, triggering and rupture in South African mines

CSIR Research Space (South Africa)

Durrheim, RJ

2012-05-01

Full Text Available Earthquakes, and the tsunamis and landslides they trigger, pose a serious risk to people living close to plate boundaries, and a lesser but still significant risk to inhabitants of stable continental regions where destructive earthquakes are rare... of experiments that seek to identify reliable precursors of damaging seismic events. 1. Introduction Earthquakes, and the tsunamis and landslides they trigger, pose a serious risk to people living close to plate boundaries, and a lesser but still significant...

Why local people did not present a problem in the 2016 Kumamoto earthquake, Japan though people accused in the 2009 L'Aquila earthquake?

Science.gov (United States)

Sugimoto, M.

2016-12-01

Risk communication is a big issues among seismologists after the 2009 L'Aquila earthquake all over the world. A lot of people remember 7 researchers as "L'Aquila 7" were accused in Italy. Seismologists said it is impossible to predict an earthquake by science technology today and join more outreach activities. "In a subsequent inquiry of the handling of the disaster, seven members of the Italian National Commission for the Forecast and Prevention of Major Risks were accused of giving "inexact, incomplete and contradictory" information about the danger of the tremors prior to the main quake. On 22 October 2012, six scientists and one ex-government official were convicted of multiple manslaughter for downplaying the likelihood of a major earthquake six days before it took place. They were each sentenced to six years' imprisonment (Wikipedia)". Finally 6 scientists are not guilty. The 2016 Kumamoto earthquake hit Kyushu, Japan in April. They are very similar seismological situations between the 2016 Kumamoto earthquake and the 2009 L'Aquila earthquake. The foreshock was Mj6.5 and Mw6.2 in 14 April 2016. The main shock was Mj7.3 and Mw7.0. Japan Metrological Agency (JMA) misleaded foreshock as mainshock before main shock occured. 41 people died by the main shock in Japan. However local people did not accused scientists in Japan. It has been less big earhquakes around 100 years in Kumamoto. Poeple was not so matured that they treated earthquake information in Kyushu, Japan. How are there differences between Japan and Italy? We learn about outreach activities for sciencits from this case.

The 2012 Mw5.6 earthquake in Sofia seismogenic zone - is it a slow earthquake

Science.gov (United States)

Raykova, Plamena; Solakov, Dimcho; Slavcheva, Krasimira; Simeonova, Stela; Aleksandrova, Irena

2017-04-01

Recently our understanding of tectonic faulting has been shaken by the discoveries of seismic tremor, low frequency earthquakes, slow slip events, and other models of fault slip. These phenomenas represent models of failure that were thought to be non-existent and theoretically impossible only a few years ago. Slow earthquakes are seismic phenomena in which the rupture of geological faults in the earth's crust occurs gradually without creating strong tremors. Despite the growing number of observations of slow earthquakes their origin remains unresolved. Studies show that the duration of slow earthquakes ranges from a few seconds to a few hundred seconds. The regular earthquakes with which most people are familiar release a burst of built-up stress in seconds, slow earthquakes release energy in ways that do little damage. This study focus on the characteristics of the Mw5.6 earthquake occurred in Sofia seismic zone on May 22nd, 2012. The Sofia area is the most populated, industrial and cultural region of Bulgaria that faces considerable earthquake risk. The Sofia seismic zone is located in South-western Bulgaria - the area with pronounce tectonic activity and proved crustal movement. In 19th century the city of Sofia (situated in the centre of the Sofia seismic zone) has experienced two strong earthquakes with epicentral intensity of 10 MSK. During the 20th century the strongest event occurred in the vicinity of the city of Sofia is the 1917 earthquake with MS=5.3 (I0=7-8 MSK64).The 2012 quake occurs in an area characterized by a long quiescence (of 95 years) for moderate events. Moreover, a reduced number of small earthquakes have also been registered in the recent past. The Mw5.6 earthquake is largely felt on the territory of Bulgaria and neighbouring countries. No casualties and severe injuries have been reported. Mostly moderate damages were observed in the cities of Pernik and Sofia and their surroundings. These observations could be assumed indicative for a

On the relation of earthquake stress drop and ground motion variability

Science.gov (United States)

Oth, Adrien; Miyake, Hiroe; Bindi, Dino

2017-07-01

One of the key parameters for earthquake source physics is stress drop since it can be directly linked to the spectral level of ground motion. Stress drop estimates from moment corner frequency analysis have been shown to be extremely variable, and this to a much larger degree than expected from the between-event ground motion variability. This discrepancy raises the question whether classically determined stress drop variability is too large, which would have significant consequences for seismic hazard analysis. We use a large high-quality data set from Japan with well-studied stress drop data to address this issue. Nonparametric and parametric reference ground motion models are derived, and the relation of between-event residuals for Japan Meteorological Agency equivalent seismic intensity and peak ground acceleration with stress drop is analyzed for crustal earthquakes. We find a clear correlation of the between-event residuals with stress drops estimates; however, while the island of Kyushu is characterized by substantially larger stress drops than Honshu, the between-event residuals do not reflect this observation, leading to the appearance of two event families with different stress drop levels yet similar range of between-event residuals. Both the within-family and between-family stress drop variations are larger than expected from the ground motion between-event variability. A systematic common analysis of these parameters holds the potential to provide important constraints on the relative robustness of different groups of data in the different parameter spaces and to improve our understanding on how much of the observed source parameter variability is likely to be true source physics variability.

Earthquake occurrence as stochastic event: (1) theoretical models

Energy Technology Data Exchange (ETDEWEB)

Basili, A.; Basili, M.; Cagnetti, V.; Colombino, A.; Jorio, V.M.; Mosiello, R.; Norelli, F.; Pacilio, N.; Polinari, D.

1977-01-01

The present article intends liaisoning the stochastic approach in the description of earthquake processes suggested by Lomnitz with the experimental evidence reached by Schenkova that the time distribution of some earthquake occurrence is better described by a Negative Bionomial distribution than by a Poisson distribution. The final purpose of the stochastic approach might be a kind of new way for labeling a given area in terms of seismic risk.

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.

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)

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

deepest, offering a comprehensive characterization of sediment remobilization by a transform earthquake. These and other modern case studies will improve our ability to recognize earthquake-related sedimentation events, to differentiate them from other causes, and to decipher in them important characteristics of the earthquakes.

Seismic risk analysis for the Westinghouse Electric facility, Cheswick, Pennsylvania

International Nuclear Information System (INIS)

1977-01-01

This report presents the results of a detailed seismic risk analysis of the Westinghouse Electric plutonium fuel development facility at Cheswick, Pennsylvania. This report focuses on earthquakes. The historical seismic record was established after a review of available literature, consultation with operators of local seismic arrays and examination of appropriate seismic data bases. Because of the aseismicity of the region around the site, an analysis different from the conventional closest approach in a tectonic province was adapted. Earthquakes as far from the site as 1,000 km were included, as were the possibility of earthquakes at the site. In addition, various uncertainties in the input were explicitly considered in the analysis. For example, allowance was made for both the uncertainty in predicting maximum possible earthquakes in the region and the effect of the dispersion of data about the best fit attenuation relation. The attenuation relationship is derived from two of the most recent, advanced studies relating earthquake intensity reports and acceleration. Results of the risk analysis, which include a Bayesian estimate of the uncertainties, are presented as return period accelerations. The best estimate curve indicates that the Westinghouse facility will experience 0.05 g every 220 years and 0.10 g every 1400 years. The accelerations are very insensitive to the details of the source region geometries or the historical earthquake statistics in each region and each of the source regions contributes almost equally to the cumulative risk at the site

Behavioral Response in the Immediate Aftermath of Shaking: Earthquakes in Christchurch and Wellington, New Zealand, and Hitachi, Japan

Directory of Open Access Journals (Sweden)

Ihnji Jon

2016-11-01

Full Text Available This study examines people’s response actions in the first 30 min after shaking stopped following earthquakes in Christchurch and Wellington, New Zealand, and Hitachi, Japan. Data collected from 257 respondents in Christchurch, 332 respondents in Hitachi, and 204 respondents in Wellington revealed notable similarities in some response actions immediately after the shaking stopped. In all four events, people were most likely to contact family members and seek additional information about the situation. However, there were notable differences among events in the frequency of resuming previous activities. Actions taken in the first 30 min were weakly related to: demographic variables, earthquake experience, contextual variables, and actions taken during the shaking, but were significantly related to perceived shaking intensity, risk perception and affective responses to the shaking, and damage/infrastructure disruption. These results have important implications for future research and practice because they identify promising avenues for emergency managers to communicate seismic risks and appropriate responses to risk area populations.

Scientific, Engineering, and Financial Factors of the 1989 Human-Triggered Newcastle Earthquake in Australia

Science.gov (United States)

Klose, C. D.

2006-12-01

This presentation emphasizes the dualism of natural resources exploitation and economic growth versus geomechanical pollution and risks of human-triggered earthquakes. Large-scale geoengineering activities, e.g., mining, reservoir impoundment, oil/gas production, water exploitation or fluid injection, alter pre-existing lithostatic stress states in the earth's crust and are anticipated to trigger earthquakes. Such processes of in- situ stress alteration are termed geomechanical pollution. Moreover, since the 19th century more than 200 earthquakes have been documented worldwide with a seismic moment magnitude of 4.5losses of triggered earthquakes. An hazard assessment, based on a geomechanical crust model, shows that only four deep coal mines were responsible for triggering this severe earthquake. A small-scale economic risk assessment identifies that the financial loss due to earthquake damage has reduced mining profits that have been re-invested in the Newcastle region for over two centuries beginning in 1801. Furthermore, large-scale economic risk assessment reveals that the financial loss is equivalent to 26% of the Australian Gross Domestic Product (GDP) growth in 1988/89. These costs account for 13% of the total costs of all natural disasters (e.g., flooding, drought, wild fires) and 94% of the costs of all earthquakes recorded in Australia between 1967 and 1999. In conclusion, the increasing number and size of geoengineering activities, such as coal mining near Newcastle or planned carbon dioxide Geosequestration initiatives, represent a growing hazard potential, which can negatively affect socio-economic growth and sustainable development. Finally, hazard and risk degrees, based on geomechanical-mathematical models, can be forecasted in space and over time for urban planning in order to prevent economic losses of human-triggered earthquakes in the future.

Earthquake Risk Management of Underground Lifelines in the Urban Area of Catania

International Nuclear Information System (INIS)

Grasso, S.; Maugeri, M.

2008-01-01

Lifelines typically include the following five utility networks: potable water, sewage natural gas, electric power, telecommunication and transportation system. The response of lifeline systems, like gas and water networks, during a strong earthquake, can be conveniently evaluated with the estimated average number of ruptures per km of pipe. These ruptures may be caused either by fault ruptures crossing, or by permanent deformations of the soil mass (landslides, liquefaction), or by transient soil deformations caused by seismic wave propagation. The possible consequences of damaging earthquakes on transportation systems may be the reduction or the interruption of traffic flow, as well as the impact on the emergency response and on the recovery assistance. A critical element in the emergency management is the closure of roads due to fallen obstacles and debris of collapsed buildings.The earthquake-induced damage to buried pipes is expressed in terms of repair rate (RR), defined as the number of repairs divided by the pipe length (km) exposed to a particular level of seismic demand; this number is a function of the pipe material (and joint type), of the pipe diameter and of the ground shaking level, measured in terms of peak horizontal ground velocity (PGV) or permanent ground displacement (PGD). The development of damage algorithms for buried pipelines is primarily based on empirical evidence, tempered with engineering judgment and sometimes by analytical formulations.For the city of Catania, in the present work use has been made of the correlation between RR and peak horizontal ground velocity by American Lifelines Alliance (ALA, 2001), for the verifications of main buried pipelines. The performance of the main buried distribution networks has been evaluated for the Level I earthquake scenario (January 11, 1693 event I = XI, M 7.3) and for the Level II earthquake scenario (February 20, 1818 event I = IX, M 6.2).Seismic damage scenario of main gas pipelines and

Strong motion duration and earthquake magnitude relationships

International Nuclear Information System (INIS)

Salmon, M.W.; Short, S.A.; Kennedy, R.P.

1992-06-01

Earthquake duration is the total time of ground shaking from the arrival of seismic waves until the return to ambient conditions. Much of this time is at relatively low shaking levels which have little effect on seismic structural response and on earthquake damage potential. As a result, a parameter termed ''strong motion duration'' has been defined by a number of investigators to be used for the purpose of evaluating seismic response and assessing the potential for structural damage due to earthquakes. This report presents methods for determining strong motion duration and a time history envelope function appropriate for various evaluation purposes, for earthquake magnitude and distance, and for site soil properties. There are numerous definitions of strong motion duration. For most of these definitions, empirical studies have been completed which relate duration to earthquake magnitude and distance and to site soil properties. Each of these definitions recognizes that only the portion of an earthquake record which has sufficiently high acceleration amplitude, energy content, or some other parameters significantly affects seismic response. Studies have been performed which indicate that the portion of an earthquake record in which the power (average rate of energy input) is maximum correlates most closely with potential damage to stiff nuclear power plant structures. Hence, this report will concentrate on energy based strong motion duration definitions

GPS Analyses of the Sumatra-Andaman Earthquake

DEFF Research Database (Denmark)

Khan, Shfaqat Abbas; Gudmundsson, Ólafur

2005-01-01

The Sumatra, Indonesia, earthquake on 26 December 2004 was one of the most devastating earthquakes in history. With a magnitude of M w = 9.3 (revised based on normal-mode amplitudes by Stein and Okal, http://www.earth.northwestern.edu/people/seth/research/sumatra.html), it is the second largest...... earthquake recorded since 1900. It occurred about 100 km off the west coast of northern Sumatra, where the relatively dense Indo-Australian plate moves beneath the lighter Burma plate, resulting in stress accumulation. The average relative velocity of the two plates is about 6 cm/yr. On 26 December 2004...

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

Science.gov (United States)

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.

Impact of earthquake-induced tsunamis on public health

Science.gov (United States)

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

2017-04-01

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

Transient postseismic mantle relaxation following 2004 Sumatra earthquake: implications of seismic vulnerability in the Andaman-Nicobar region

Directory of Open Access Journals (Sweden)

C. D. Reddy

2012-02-01

Full Text Available Throughout the world, the tsunami generation potential of some large under-sea earthquakes significantly contributes to regional seismic hazard, which gives rise to significant risk in the near-shore provinces where human settlements are in sizeable population, often referred to as coastal seismic risk. In this context, we show from the pertinent GPS data that the transient stresses generated by the viscoelastic relaxation process taking place in the mantle is capable of rupturing major faults by stress transfer from the mantle through the lower crust including triggering additional rupture on the other major faults. We also infer that postseismic relaxation at relatively large depths can push some of the fault segments to reactivation causing failure sequences. As an illustration to these effects, we consider in detail the earthquake sequence comprising six events, starting from the main event of M_w = 7.5, on 10 August 2009 and tapering off to a small earthquake of M_w = 4.5 on 2 February 2011 over a period of eighteen months in the intensely seismic Andaman Islands between India and Myanmar. The persisting transient stresses, spatio-temporal seismic pattern, modeled Coulomb stress changes, and the southward migration of earthquake activity has increased the probability of moderate earthquakes recurring in the northern Andaman region, particularly closer to or somewhat south of Diglipur.

78 FR 64973 - Scientific Earthquake Studies Advisory Committee (SESAC)

Science.gov (United States)

2013-10-30

... DEPARTMENT OF THE INTERIOR Geological Survey [GX14GG009950000] Scientific Earthquake Studies... Public Law 106-503, the Scientific Earthquake Studies Advisory Committee (SESAC) will hold its next... Survey (USGS) on matters relating to the USGS's participation in the National Earthquake Hazards...

76 FR 19123 - National Earthquake Prediction Evaluation Council (NEPEC)

Science.gov (United States)

2011-04-06

... Earthquake Prediction Evaluation Council (NEPEC) AGENCY: U.S. Geological Survey, Interior. ACTION: Notice of meeting. SUMMARY: Pursuant to Public Law 96-472, the National Earthquake Prediction Evaluation Council... proposed earthquake predictions, on the completeness and scientific validity of the available data related...

Safety and survival in an earthquake

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,

1969-01-01

Many earth scientists in this country and abroad are focusing their studies on the search for means of predicting impending earthquakes, but, as yet, an accurate prediction of the time and place of such an event cannot be made. From past experience, however, one can assume that earthquakes will continue to harass mankind and that they will occur most frequently in the areas where they have been relatively common in the past. In the United States, earthquakes can be expected to occur most frequently in the western states, particularly in Alaska, California, Washington, Oregon, Nevada, Utah, and Montana. The danger, however, is not confined to any one part of the country; major earthquakes have occurred at widely scattered locations.

Immediate behavioural responses to earthquakes in Christchurch, New Zealand, and Hitachi, Japan.

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Lindell, Michael K; Prater, Carla S; Wu, Hao Che; Huang, Shih-Kai; Johnston, David M; Becker, Julia S; Shiroshita, Hideyuki

2016-01-01

This study examines people's immediate responses to earthquakes in Christchurch, New Zealand, and Hitachi, Japan. Data collected from 257 respondents in Christchurch and 332 respondents in Hitachi revealed notable similarities between the two cities in people's emotional reactions, risk perceptions, and immediate protective actions during the events. Respondents' physical, household, and social contexts were quite similar, but Hitachi residents reported somewhat higher levels of emotional reaction and risk perception than did Christchurch residents. Contrary to the recommendations of emergency officials, the most frequent response of residents in both cities was to freeze. Christchurch residents were more likely than Hitachi residents to drop to the ground and take cover, whereas Hitachi residents were more likely than Christchurch residents to evacuate immediately the building in which they were situated. There were relatively small correlations between immediate behavioural responses and demographic characteristics, earthquake experience, and physical, social, or household context. © 2016 The Author(s). Disasters © Overseas Development Institute, 2016.

Isolating social influences on vulnerability to earthquake shaking: identifying cost-effective mitigation strategies.

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Bhloscaidh, Mairead Nic; McCloskey, John; Pelling, Mark; Naylor, Mark

2013-04-01

Until expensive engineering solutions become more universally available, the objective targeting of resources at demonstrably effective, low-cost interventions might help reverse the trend of increasing mortality in earthquakes. Death tolls in earthquakes are the result of complex interactions between physical effects, such as the exposure of the population to strong shaking, and the resilience of the exposed population along with supporting critical infrastructures and institutions. The identification of socio-economic factors that contribute to earthquake mortality is crucial to identifying and developing successful risk management strategies. Here we develop a quantitative methodology more objectively to assess the ability of communities to withstand earthquake shaking, focusing on, in particular, those cases where risk management performance appears to exceed or fall below expectations based on economic status. Using only published estimates of the shaking intensity and population exposure for each earthquake, data that is available for earthquakes in countries irrespective of their level of economic development, we develop a model for mortality based on the contribution of population exposure to shaking only. This represents an attempt to remove, as far as possible, the physical causes of mortality from our analysis (where we consider earthquake engineering to reduce building collapse among the socio-economic influences). The systematic part of the variance with respect to this model can therefore be expected to be dominated by socio-economic factors. We find, as expected, that this purely physical analysis partitions countries in terms of basic socio-economic measures, for example GDP, focusing analytical attention on the power of economic measures to explain variance in observed distributions of earthquake risk. The model allows the definition of a vulnerability index which, although broadly it demonstrates the expected income-dependence of vulnerability to

Napa earthquake: An earthquake in a highly connected world

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Bossu, R.; Steed, R.; Mazet-Roux, G.; Roussel, F.

2014-12-01

The Napa earthquake recently occurred close to Silicon Valley. This makes it a good candidate to study what social networks, wearable objects and website traffic analysis (flashsourcing) can tell us about the way eyewitnesses react to ground shaking. In the first part, we compare the ratio of people publishing tweets and with the ratio of people visiting EMSC (European Mediterranean Seismological Centre) real time information website in the first minutes following the earthquake occurrence to the results published by Jawbone, which show that the proportion of people waking up depends (naturally) on the epicentral distance. The key question to evaluate is whether the proportions of inhabitants tweeting or visiting the EMSC website are similar to the proportion of people waking up as shown by the Jawbone data. If so, this supports the premise that all methods provide a reliable image of the relative ratio of people waking up. The second part of the study focuses on the reaction time for both Twitter and EMSC website access. We show, similarly to what was demonstrated for the Mineral, Virginia, earthquake (Bossu et al., 2014), that hit times on the EMSC website follow the propagation of the P waves and that 2 minutes of website traffic is sufficient to determine the epicentral location of an earthquake on the other side of the Atlantic. We also compare with the publication time of messages on Twitter. Finally, we check whether the number of tweets and the number of visitors relative to the number of inhabitants is correlated to the local level of shaking. Together these results will tell us whether the reaction of eyewitnesses to ground shaking as observed through Twitter and the EMSC website analysis is tool specific (i.e. specific to Twitter or EMSC website) or whether they do reflect people's actual reactions.

Determination of Road Functionality for Küçükçekmece District Following a Scenario Earthquake for Istanbul

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Betül Ergün Konukcu

2016-03-01

Full Text Available Istanbul has been affected by earthquakes throughout its history. The most recent earthquake to shake Istanbul was on August 17 1999, along the North Anatolian Fault, 12 km southeast of the Izmit Province, with a magnitude of 7.4. Following the 1999 Izmit earthquake, the earthquake risk in Istanbul started to draw attention and many scientific studies were conducted on the potential earthquake risk in this city. Based on these studies, predictions are that Istanbul is going to face a major earthquake in the near future and this will cause severe damage to the built environment. It is estimated that the damage caused by the anticipated earthquake will be extensive as a consequence of Istanbul’s low quality building stock of Istanbul. The buildings that have the possibility of being damaged cause debris around them. If roadside buildings collapsed during the earthquake, the scattered parts of the buildings could cause roads to lose their functionality. Not only building damage but also transportation damage analysis is necessary to use risk mitigation studies and decisions, being that experiences showed that the functionality of transportation structure effects post-earthquake emergency response and recovery operation seriously. This study aims to reveal a method for road functionality in Küçükçekçekmece following a potential Istanbul Earthquake by using building collapse direction and bridge damage.

The induced earthquake sequence related to the St. Gallen deep geothermal project (Switzerland): Fault reactivation and fluid interactions imaged by microseismicity

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Diehl, T.; Kraft, T.; Kissling, E.; Wiemer, S.

2017-09-01

In July 2013, a sequence of more than 340 earthquakes was induced by reservoir stimulations and well-control procedures following a gas kick at a deep geothermal drilling project close to the city of St. Gallen, Switzerland. The sequence culminated in an ML 3.5 earthquake, which was felt within 10-15 km from the epicenter. High-quality earthquake locations and 3-D reflection seismic data acquired in the St. Gallen project provide a unique data set, which allows high-resolution studies of earthquake triggering related to the injection of fluids into macroscopic fault zones. In this study, we present a high-precision earthquake catalog of the induced sequence. Absolute locations are constrained by a coupled hypocenter-velocity inversion, and subsequent double-difference relocations image the geometry of the ML 3.5 rupture and resolve the spatiotemporal evolution of seismicity. A joint interpretation of earthquake and seismic data shows that the majority of the seismicity occurred in the pre-Mesozoic basement, hundreds of meters below the borehole and the targeted Mesozoic sequence. We propose a hydraulic connectivity between the reactivated fault and the borehole, likely through faults mapped by seismic data. Despite the excellent quality of the seismic data, the association of seismicity with mapped faults remains ambiguous. In summary, our results document that the actual hydraulic properties of a fault system and hydraulic connections between its fault segments are complex and may not be predictable upfront. Incomplete knowledge of fault structures and stress heterogeneities within highly complex fault systems additionally challenge the degree of predictability of induced seismicity related to underground fluid injections.

Injuries and Traumatic Psychological Exposures Associated with the South Napa Earthquake - California, 2014.

Science.gov (United States)

Attfield, Kathleen R; Dobson, Christine B; Henn, Jennifer B; Acosta, Meileen; Smorodinsky, Svetlana; Wilken, Jason A; Barreau, Tracy; Schreiber, Merritt; Windham, Gayle C; Materna, Barbara L; Roisman, Rachel

2015-09-11

On August 24, 2014, at 3:20 a.m., a magnitude 6.0 earthquake struck California, with its epicenter in Napa County (1). The earthquake was the largest to affect the San Francisco Bay area in 25 years and caused significant damage in Napa and Solano counties, including widespread power outages, five residential fires, and damage to roadways, waterlines, and 1,600 buildings (2). Two deaths resulted (2). On August 25, Napa County Public Health asked the California Department of Public Health (CDPH) for assistance in assessing postdisaster health effects, including earthquake-related injuries and effects on mental health. On September 23, Solano County Public Health requested similar assistance. A household-level Community Assessment for Public Health Emergency Response (CASPER) was conducted for these counties in two cities (Napa, 3 weeks after the earthquake, and Vallejo, 6 weeks after the earthquake). Among households reporting injuries, a substantial proportion (48% in Napa and 37% in western Vallejo) reported that the injuries occurred during the cleanup period, suggesting that increased messaging on safety precautions after a disaster might be needed. One fifth of respondents overall (27% in Napa and 9% in western Vallejo) reported one or more traumatic psychological exposures in their households. These findings were used by Napa County Mental Health to guide immediate-term mental health resource allocations and to conduct public training sessions and education campaigns to support persons with mental health risks following the earthquake. In addition, to promote community resilience and future earthquake preparedness, Napa County Public Health subsequently conducted community events on the earthquake anniversary and provided outreach workers with psychological first aid training.

Earthquake induced liquefaction hazard, probability and risk assessment in the city of Kolkata, India: its historical perspective and deterministic scenario

Science.gov (United States)

Nath, Sankar Kumar; Srivastava, Nishtha; Ghatak, Chitralekha; Adhikari, Manik Das; Ghosh, Ambarish; Sinha Ray, S. P.

2018-01-01

Liquefaction-induced ground failure is one amongst the leading causes of infrastructure damage due to the impact of large earthquakes in unconsolidated, non-cohesive, water saturated alluvial terrains. The city of Kolkata is located on the potentially liquefiable alluvial fan deposits of Ganga-Bramhaputra-Meghna Delta system with subsurface litho-stratigraphic sequence comprising of varying percentages of clay, cohesionless silt, sand, and gravel interbedded with decomposed wood and peat. Additionally, the region has moderately shallow groundwater condition especially in the post-monsoon seasons. In view of burgeoning population, there had been unplanned expansion of settlements in the hazardous geological, geomorphological, and hydrological conditions exposing the city to severe liquefaction hazard. The 1897 Shillong and 1934 Bihar-Nepal earthquakes both of M w 8.1 reportedly induced Modified Mercalli Intensity of IV-V and VI-VII respectively in the city reportedly triggering widespread to sporadic liquefaction condition with surface manifestation of sand boils, lateral spreading, ground subsidence, etc., thus posing a strong case for liquefaction potential analysis in the terrain. With the motivation of assessing seismic hazard, vulnerability, and risk of the city of Kolkata through a consorted federal funding stipulated for all the metros and upstart urban centers in India located in BIS seismic zones III, IV, and V with population more than one million, an attempt has been made here to understand the liquefaction susceptibility condition of Kolkata under the impact of earthquake loading employing modern multivariate techniques and also to predict deterministic liquefaction scenario of the city in the event of a probabilistic seismic hazard condition with 10% probability of exceedance in 50 years and a return period of 475 years. We conducted in-depth geophysical and geotechnical investigations in the city encompassing 435 km2 area. The stochastically

Posttraumatic stress disorder and posttraumatic growth coexistence and the risk factors in Wenchuan earthquake survivors.

Science.gov (United States)

Wu, Zhibin; Xu, Jiuping; Sui, Yan

2016-03-30

Various studies have assessed the negative and/or positive changes in the aftermath of traumatic events. Yet few of these have addressed the factors associated with the coexistence of both negative and positive changes after a devastating earthquake. The aim of this study is to assess the relationship between the negative and positive changes and elucidate the risk factors of such changes one year after Wenchuan earthquake. A total of 2080 survivors from 19 counties participated in a self-report questionnaire survey which included the posttraumatic stress disorder (PTSD) Check list-Civilian, the posttraumatic growth PTG Inventory (PTGI). The prevalence of PTSD and moderate PTG was found to be 40.1% (95% CI [37.9% 42.3%]) and 51.1% (95% CI [48.9% 53.3%]). The PTSD and moderate PTG coexistence was 19.6% (95% CI [17.8% 21.4%]). PTSD symptom severity was significantly positively associated with the PTG score. Middle aged groups (31-40 and 41-50 years old, OR=2.323, 95% CI [1.059, 5.095] and OR=2.410, 95% CI [1.090, 5.329] respectively), those with lower income levels (OR=8.019, 95% CI [2.421, 26.558]), those living in temporary house (OR=1.946, 95% CI [1.280, 2.956]), and those who had had less social support (OR=1.109, 95% CI [1.076, 1.143]) had a significantly higher possibility for the presence of PTSD and moderate PTG coexistence. The results indicated the widespread positive changes in earthquake survivors. Better income levels and living conditions and higher social support were suggested to promote PTG in those with PTSD. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

Induced seismicity provides insight into why earthquake ruptures stop

KAUST Repository

Galis, Martin

2017-12-21

Injection-induced earthquakes pose a serious seismic hazard but also offer an opportunity to gain insight into earthquake physics. Currently used models relating the maximum magnitude of injection-induced earthquakes to injection parameters do not incorporate rupture physics. We develop theoretical estimates, validated by simulations, of the size of ruptures induced by localized pore-pressure perturbations and propagating on prestressed faults. Our model accounts for ruptures growing beyond the perturbed area and distinguishes self-arrested from runaway ruptures. We develop a theoretical scaling relation between the largest magnitude of self-arrested earthquakes and the injected volume and find it consistent with observed maximum magnitudes of injection-induced earthquakes over a broad range of injected volumes, suggesting that, although runaway ruptures are possible, most injection-induced events so far have been self-arrested ruptures.

Swedish earthquakes and acceleration probabilities

International Nuclear Information System (INIS)

Slunga, R.

1979-03-01

A method to assign probabilities to ground accelerations for Swedish sites is described. As hardly any nearfield instrumental data is available we are left with the problem of interpreting macroseismic data in terms of acceleration. By theoretical wave propagation computations the relation between seismic strength of the earthquake, focal depth, distance and ground accelerations are calculated. We found that most Swedish earthquake of the area, the 1904 earthquake 100 km south of Oslo, is an exception and probably had a focal depth exceeding 25 km. For the nuclear power plant sites an annual probability of 10 -5 has been proposed as interesting. This probability gives ground accelerations in the range 5-20 % for the sites. This acceleration is for a free bedrock site. For consistency all acceleration results in this study are given for bedrock sites. When applicating our model to the 1904 earthquake and assuming the focal zone to be in the lower crust we get the epicentral acceleration of this earthquake to be 5-15 % g. The results above are based on an analyses of macrosismic data as relevant instrumental data is lacking. However, the macroseismic acceleration model deduced in this study gives epicentral ground acceleration of small Swedish earthquakes in agreement with existent distant instrumental data. (author)

Geomorphic legacy of medieval Himalayan earthquakes in the Pokhara Valley

Science.gov (United States)

Schwanghart, Wolfgang; Bernhardt, Anne; Stolle, Amelie; Hoelzmann, Philipp; Adhikari, Basanta R.; Andermann, Christoff; Tofelde, Stefanie; Merchel, Silke; Rugel, Georg; Fort, Monique; Korup, Oliver

2016-04-01

The Himalayas and their foreland belong to the world's most earthquake-prone regions. With millions of people at risk from severe ground shaking and associated damages, reliable data on the spatial and temporal occurrence of past major earthquakes is urgently needed to inform seismic risk analysis. Beyond the instrumental record such information has been largely based on historical accounts and trench studies. Written records provide evidence for damages and fatalities, yet are difficult to interpret when derived from the far-field. Trench studies, in turn, offer information on rupture histories, lengths and displacements along faults but involve high chronological uncertainties and fail to record earthquakes that do not rupture the surface. Thus, additional and independent information is required for developing reliable earthquake histories. Here, we present exceptionally well-dated evidence of catastrophic valley infill in the Pokhara Valley, Nepal. Bayesian calibration of radiocarbon dates from peat beds, plant macrofossils, and humic silts in fine-grained tributary sediments yields a robust age distribution that matches the timing of nearby M>8 earthquakes in ~1100, 1255, and 1344 AD. The upstream dip of tributary valley fills and X-ray fluorescence spectrometry of their provenance rule out local sediment sources. Instead, geomorphic and sedimentary evidence is consistent with catastrophic fluvial aggradation and debris flows that had plugged several tributaries with tens of meters of calcareous sediment from the Annapurna Massif >60 km away. The landscape-changing consequences of past large Himalayan earthquakes have so far been elusive. Catastrophic aggradation in the wake of two historically documented medieval earthquakes and one inferred from trench studies underscores that Himalayan valley fills should be considered as potential archives of past earthquakes. Such valley fills are pervasive in the Lesser Himalaya though high erosion rates reduce

Maximum magnitude of injection-induced earthquakes: A criterion to assess the influence of pressure migration along faults

Science.gov (United States)

Norbeck, Jack H.; Horne, Roland N.

2018-05-01

The maximum expected earthquake magnitude is an important parameter in seismic hazard and risk analysis because of its strong influence on ground motion. In the context of injection-induced seismicity, the processes that control how large an earthquake will grow may be influenced by operational factors under engineering control as well as natural tectonic factors. Determining the relative influence of these effects on maximum magnitude will impact the design and implementation of induced seismicity management strategies. In this work, we apply a numerical model that considers the coupled interactions of fluid flow in faulted porous media and quasidynamic elasticity to investigate the earthquake nucleation, rupture, and arrest processes for cases of induced seismicity. We find that under certain conditions, earthquake ruptures are confined to a pressurized region along the fault with a length-scale that is set by injection operations. However, earthquakes are sometimes able to propagate as sustained ruptures outside of the zone that experienced a pressure perturbation. We propose a faulting criterion that depends primarily on the state of stress and the earthquake stress drop to characterize the transition between pressure-constrained and runaway rupture behavior.

Expanding Horizons in Mitigating Earthquake Related Disasters in Urban Areas: Global Development of Real-Time Seismology

OpenAIRE

Utkucu, Murat; Küyük, Hüseyin Serdar; Demir, İsmail Hakkı

2016-01-01

Abstract Real-time seismology is a newly developing alternative approach in seismology to mitigate earthquake hazard. It exploits up-to-date advances in seismic instrument technology, data acquisition, digital communications and computer systems for quickly transforming data into earthquake information in real-time to reduce earthquake losses and its impact on social and economic life in the earthquake prone densely populated urban and industrial areas.  Real-time seismology systems are not o...

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

Science.gov (United States)

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

Who is Responsible for Human Suffering due to Earthquakes?

Science.gov (United States)

Wyss, M.

2012-12-01

A court in L'Aquila, Italy, convicted seven to six years in prison and a combined fine of two million Euros for not following their "obligation to avoid death, injury and damage, or at least to minimize them," as the prosecution alleged. These men lose their jobs and pensions, and are banned from holding public office. Meanwhile, the town of L'Aquila is teeming with furious citizens, who are preparing additional civil suits against the defendants, whom they hold responsible for the deaths of their loved ones, killed by collapsing buildings during the magnitude 6.3 earthquake of April 6, 2009. Before this shock, an earthquake swarm had scared the inhabitants for several weeks. To calm the population, the vice-director of the Department of Civil Protection (DCP) called a meeting of the Italian Commission of Great Risks (CGR) in L'Aquila to assess the situation on March 31. One hour before this meeting, the vice-director stated in a TV interview that the seismic situation in L'Aquila was "certainly normal" and posed "no danger" and he added that "the scientific community continues to assure me that, to the contrary, it's a favorable situation because of the continuous discharge of energy." This statement is untrue in two ways. Firstly, small earthquakes do not release enough strain energy to reduce the potential for a large shock, and secondly no seismologist would make such a statement because we know it is not true. However, the population clung to the idea: "the more tremors, the less danger". People who lost relatives allege that they would have left their homes, had they not been falsely assured of their safety. The court treated all seven alike, although they had very different functions and obligations. Two were leaders in DCP, four were members of the CGR, and one was a seismology expert, who brought the latest seismic data. The minutes of the meeting show that none of the experts said anything wrong. They all stated that the probability of a main shock to

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.

Catalog of Hawaiian earthquakes, 1823-1959

Science.gov (United States)

Klein, Fred W.; Wright, Thomas L.

2000-01-01

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

Vulnerability assessment of archaeological sites to earthquake hazard: An indicator based method integrating spatial and temporal aspects

Directory of Open Access Journals (Sweden)

Despina Minos-Minopoulos

2017-07-01

Full Text Available Across the world, numerous sites of cultural heritage value are at risk from a variety of human-induced and natural hazards such as war and earthquakes. Here we present and test a novel indicator-based method for assessing the vulnerability of archaeological sites to earthquakes. Vulnerability is approached as a dynamic element assessed through a combination of spatial and temporal parameters. The spatial parameters examine the susceptibility of the sites to the secondary Earthquake Environmental Effects of ground liquefaction, landslides and tsunami and are expressed through the Spatial Susceptibility Index (SSi. Parameters of physical vulnerability, economic importance and visitors density examine the temporal vulnerability of the sites expressed through the Temporal Vulnerability Index (TVi. The equally weighted sum of the spatial and temporal indexes represents the total Archaeological Site Vulnerability Index (A.S.V.I.. The A.S.V.I method is applied at 16 archaeological sites across Greece, allowing an assessment of their vulnerability. This then allows the establishment of a regional and national priority list for considering future risk mitigation. Results indicate that i the majority of the sites have low to moderate vulnerability to earthquake hazard, ii Neratzia Fortress on Kos and Heraion on Samos are characterised as highly vulnerable and should be prioritised for further studies and mitigation measures, and iii the majority of the sites are susceptible to at least one Earthquake Environmental Effect and present relatively high physical vulnerability attributed to the existing limited conservation works. This approach highlights the necessity for an effective vulnerability assessment methodology within the existing framework of disaster risk management for cultural heritage.

Earthquake Education in Prime Time

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de Groot, R.; Abbott, P.; Benthien, M.

2004-12-01

Since 2001, the Southern California Earthquake Center (SCEC) has collaborated on several video production projects that feature important topics related to earthquake science, engineering, and preparedness. These projects have also fostered many fruitful and sustained partnerships with a variety of organizations that have a stake in hazard education and preparedness. The Seismic Sleuths educational video first appeared in the spring season 2001 on Discovery Channel's Assignment Discovery. Seismic Sleuths is based on a highly successful curriculum package developed jointly by the American Geophysical Union and The Department of Homeland Security Federal Emergency Management Agency. The California Earthquake Authority (CEA) and the Institute for Business and Home Safety supported the video project. Summer Productions, a company with a reputation for quality science programming, produced the Seismic Sleuths program in close partnership with scientists, engineers, and preparedness experts. The program has aired on the National Geographic Channel as recently as Fall 2004. Currently, SCEC is collaborating with Pat Abbott, a geology professor at San Diego State University (SDSU) on the video project Written In Stone: Earthquake Country - Los Angeles. Partners on this project include the California Seismic Safety Commission, SDSU, SCEC, CEA, and the Insurance Information Network of California. This video incorporates live-action demonstrations, vivid animations, and a compelling host (Abbott) to tell the story about earthquakes in the Los Angeles region. The Written in Stone team has also developed a comprehensive educator package that includes the video, maps, lesson plans, and other supporting materials. We will present the process that facilitates the creation of visually effective, factually accurate, and entertaining video programs. We acknowledge the need to have a broad understanding of the literature related to communication, media studies, science education, and

Application of τc*Pd in earthquake early warning

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Huang, Po-Lun; Lin, Ting-Li; Wu, Yih-Min

2015-03-01

Rapid assessment of damage potential and size of an earthquake at the station is highly demanded for onsite earthquake early warning. We study the application of τc*Pd for its estimation on the earthquake size using 123 events recorded by the borehole stations of KiK-net in Japan. The new type of earthquake size determined by τc*Pd is more related to the damage potential. We find that τc*Pd provides another parameter to measure the size of earthquake and the threshold to warn strong ground motion.

Ionospheric precursors for crustal earthquakes in Italy

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L. Perrone

2010-04-01

Full Text Available Crustal earthquakes with magnitude 6.0>M≥5.5 observed in Italy for the period 1979–2009 including the last one at L'Aquila on 6 April 2009 were considered to check if the earlier obtained relationships for ionospheric precursors for strong Japanese earthquakes are valid for the Italian moderate earthquakes. The ionospheric precursors are based on the observed variations of the sporadic E-layer parameters (h'Es, fbEs and foF2 at the ionospheric station Rome. Empirical dependencies for the seismo-ionospheric disturbances relating the earthquake magnitude and the epicenter distance are obtained and they have been shown to be similar to those obtained earlier for Japanese earthquakes. The dependences indicate the process of spreading the disturbance from the epicenter towards periphery during the earthquake preparation process. Large lead times for the precursor occurrence (up to 34 days for M=5.8–5.9 tells about a prolong preparation period. A possibility of using the obtained relationships for the earthquakes prediction is discussed.

The Need for More Earthquake Science in Southeast Asia

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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.

The use of radon as an earthquake precursor

International Nuclear Information System (INIS)

Ramola, R.C.; Singh, M.; Sandhu, A.S.; Singh, S.; Virk, H.S.

1990-01-01

Radon monitoring for earthquake prediction is part of an integral approach since the discovery of coherent and time anomalous radon concentrations prior to, during and after the 1966 Tashkent earthquake. In this paper some studies of groundwater and soil gas radon content in relation to earthquake activities are reviewed. Laboratory experiments and the development of groundwater and soil gas radon monitoring systems are described. In addition, radon monitoring studies conducted at the Guru Nanak Dev University Campus since 1986 are presented in detail. During these studies some anomalous changes in radon concentration were recorded before earthquakes occurred in the region. The anomalous radon increases are independent of meteorological conditions and appear to be caused by strain changes, which precede the earthquake. Anomalous changes in radon concentration before an earthquake suggest that radon monitoring can serve as an additional technique in the earthquake prediction programme in India. (author)

Earthquakes and Earthquake Engineering. LC Science Tracer Bullet.

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Buydos, John F., Comp.

An earthquake is a shaking of the ground resulting from a disturbance in the earth's interior. Seismology is the (1) study of earthquakes; (2) origin, propagation, and energy of seismic phenomena; (3) prediction of these phenomena; and (4) investigation of the structure of the earth. Earthquake engineering or engineering seismology includes the…

<> earthquakes: a growing contribution to the Catalogue of Strong Italian Earthquakes

Directory of Open Access Journals (Sweden)

E. Guidoboni

2000-06-01

Full Text Available The particular structure of the research into historical seismology found in this catalogue has allowed a lot of information about unknown seismic events to be traced. This new contribution to seismologic knowledge mainly consists in: i the retrieval and organisation within a coherent framework of documentary evidence of earthquakes that took place between the Middle Ages and the sixteenth century; ii the improved knowledge of seismic events, even destructive events, which in the past had been "obscured" by large earthquakes; iii the identification of earthquakes in "silent" seismic areas. The complex elements to be taken into account when dealing with unknown seismic events have been outlined; much "new" information often falls into one of the following categories: simple chronological errors relative to other well-known events; descriptions of other natural phenomena, though defined in texts as "earthquakes" (landslides, hurricanes, tornadoes, etc.; unknown tremors belonging to known seismic periods; tremors that may be connected with events which have been catalogued under incorrect dates and with very approximate estimates of location and intensity. This proves that this was not a real seismic "silence" but a research vacuum.

Uncertainties in Earthquake Loss Analysis: A Case Study From Southern California

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Mahdyiar, M.; Guin, J.

2005-12-01

Probabilistic earthquake hazard and loss analyses play important roles in many areas of risk management, including earthquake related public policy and insurance ratemaking. Rigorous loss estimation for portfolios of properties is difficult since there are various types of uncertainties in all aspects of modeling and analysis. It is the objective of this study to investigate the sensitivity of earthquake loss estimation to uncertainties in regional seismicity, earthquake source parameters, ground motions, and sites' spatial correlation on typical property portfolios in Southern California. Southern California is an attractive region for such a study because it has a large population concentration exposed to significant levels of seismic hazard. During the last decade, there have been several comprehensive studies of most regional faults and seismogenic sources. There have also been detailed studies on regional ground motion attenuations and regional and local site responses to ground motions. This information has been used by engineering seismologists to conduct regional seismic hazard and risk analysis on a routine basis. However, one of the more difficult tasks in such studies is the proper incorporation of uncertainties in the analysis. From the hazard side, there are uncertainties in the magnitudes, rates and mechanisms of the seismic sources and local site conditions and ground motion site amplifications. From the vulnerability side, there are considerable uncertainties in estimating the state of damage of buildings under different earthquake ground motions. From an analytical side, there are challenges in capturing the spatial correlation of ground motions and building damage, and integrating thousands of loss distribution curves with different degrees of correlation. In this paper we propose to address some of these issues by conducting loss analyses of a typical small portfolio in southern California, taking into consideration various source and ground

Geographic variation of clinically diagnosed mood and anxiety disorders in Christchurch after the 2010/11 earthquakes.

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

2014-11-01

The 22nd February 2011 Christchurch earthquake killed 185 people, injured over 8000, damaged over 100,000 buildings and on-going aftershocks maintained high anxiety levels. This paper examines the dose of exposure effect of earthquake damage assessments, earthquake intensity measures, liquefaction and lateral spreading on mood and anxiety disorders in Christchurch after this event. We hypothesise that such disorders are more likely to develop in people who have experienced greater exposure to these impacts within their neighborhood than others who have been less exposed, but also live in the city. For this purpose, almost all clinically diagnosed incident and relapsed cases in Christchurch in a 12 months period after the 2011 earthquake were analysed. Spatio-temporal cluster analysis shows that people living in the widely affected central and eastern parts after the 2010/11 earthquakes have a 23% higher risk of developing a mood or anxiety disorder than people living in other parts of the city. Generally, mood and anxiety-related disorders increase with closer proximity to damage from liquefaction and moderate to major lateral spreading, as well as areas that are more likely to suffer from damage in future earthquakes. Copyright © 2014 Elsevier Ltd. All rights reserved.

Analog earthquakes

International Nuclear Information System (INIS)

Hofmann, R.B.

1995-01-01

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

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

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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

Earthquake chemical precursors in groundwater: a review

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Paudel, Shukra Raj; Banjara, Sushant Prasad; Wagle, Amrita; Freund, Friedemann T.

2018-03-01

We review changes in groundwater chemistry as precursory signs for earthquakes. In particular, we discuss pH, total dissolved solids (TDS), electrical conductivity, and dissolved gases in relation to their significance for earthquake prediction or forecasting. These parameters are widely believed to vary in response to seismic and pre-seismic activity. However, the same parameters also vary in response to non-seismic processes. The inability to reliably distinguish between changes caused by seismic or pre-seismic activities from changes caused by non-seismic activities has impeded progress in earthquake science. Short-term earthquake prediction is unlikely to be achieved, however, by pH, TDS, electrical conductivity, and dissolved gas measurements alone. On the other hand, the production of free hydroxyl radicals (•OH), subsequent reactions such as formation of H2O2 and oxidation of As(III) to As(V) in groundwater, have distinctive precursory characteristics. This study deviates from the prevailing mechanical mantra. It addresses earthquake-related non-seismic mechanisms, but focused on the stress-induced electrification of rocks, the generation of positive hole charge carriers and their long-distance propagation through the rock column, plus on electrochemical processes at the rock-water interface.

ANALYSIS OF LABOUR ACCIDENTS OCCURRING IN DISASTER RESTORATION WORK FOLLOWING THE NIIGATA CHUETSU EARTHQUAKE (2004) AND THE NIIGATA CHUETSU-OKI EARTHQUAKE (2007)

Science.gov (United States)

Itoh, Kazuya; Noda, Masashi; Kikkawa, Naotaka; Hori, Tomohito; Tamate, Satoshi; Toyosawa, Yasuo; Suemasa, Naoaki

Labour accidents in disaster-relief and disaster restoration work following the Niigata Chuetsu Earthquake (2004) and the Niigata Chuetsu-oki Earthquake (2007) were analysed and characterised in order to raise awareness of the risks and hazards in such work. The Niigata Chuetsu-oki Earthquake affected houses and buildings rather than roads and railways, which are generally disrupted due to landslides or slope failures caused by earthquakes. In this scenario, the predominant type of accident is a "fall to lower level," which increases mainly due to the fact that labourers are working to repair houses and buildings. On the other hand, landslides and slope failures were much more prevalent in the Niigata Chuetsu Earthquake, resulting in more accidents occurring in geotechnical works rather than in construction works. Therefore, care should be taken in preventing "fall to lower level" accidents associated with repair work on the roofs of low-rise houses, "cut or abrasion" accidents due to the demolition of damaged houses and "caught in or compressed by equipment" accidents in road works and water and sewage works.

Children's emotional experience two years after an earthquake: An exploration of knowledge of earthquakes and associated emotions.

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Raccanello, Daniela; Burro, Roberto; Hall, Rob

2017-01-01

We explored whether and how the exposure to a natural disaster such as the 2012 Emilia Romagna earthquake affected the development of children's emotional competence in terms of understanding, regulating, and expressing emotions, after two years, when compared with a control group not exposed to the earthquake. We also examined the role of class level and gender. The sample included two groups of children (n = 127) attending primary school: The experimental group (n = 65) experienced the 2012 Emilia Romagna earthquake, while the control group (n = 62) did not. The data collection took place two years after the earthquake, when children were seven or ten-year-olds. Beyond assessing the children's understanding of emotions and regulating abilities with standardized instruments, we employed semi-structured interviews to explore their knowledge of earthquakes and associated emotions, and a structured task on the intensity of some target emotions. We applied Generalized Linear Mixed Models. Exposure to the earthquake did not influence the understanding and regulation of emotions. The understanding of emotions varied according to class level and gender. Knowledge of earthquakes, emotional language, and emotions associated with earthquakes were, respectively, more complex, frequent, and intense for children who had experienced the earthquake, and at increasing ages. Our data extend the generalizability of theoretical models on children's psychological functioning following disasters, such as the dose-response model and the organizational-developmental model for child resilience, and provide further knowledge on children's emotional resources related to natural disasters, as a basis for planning educational prevention programs.

Critical behavior in earthquake energy dissipation

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Wanliss, James; Muñoz, Víctor; Pastén, Denisse; Toledo, Benjamín; Valdivia, Juan Alejandro

2017-09-01

We explore bursty multiscale energy dissipation from earthquakes flanked by latitudes 29° S and 35.5° S, and longitudes 69.501° W and 73.944° W (in the Chilean central zone). Our work compares the predictions of a theory of nonequilibrium phase transitions with nonstandard statistical signatures of earthquake complex scaling behaviors. For temporal scales less than 84 hours, time development of earthquake radiated energy activity follows an algebraic arrangement consistent with estimates from the theory of nonequilibrium phase transitions. There are no characteristic scales for probability distributions of sizes and lifetimes of the activity bursts in the scaling region. The power-law exponents describing the probability distributions suggest that the main energy dissipation takes place due to largest bursts of activity, such as major earthquakes, as opposed to smaller activations which contribute less significantly though they have greater relative occurrence. The results obtained provide statistical evidence that earthquake energy dissipation mechanisms are essentially "scale-free", displaying statistical and dynamical self-similarity. Our results provide some evidence that earthquake radiated energy and directed percolation belong to a similar universality class.

Marmara Island earthquakes, of 1265 and 1935; Turkey

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Y. Altınok

2006-01-01

Full Text Available The long-term seismicity of the Marmara Sea region in northwestern Turkey is relatively well-recorded. Some large and some of the smaller events are clearly associated with fault zones known to be seismically active, which have distinct morphological expressions and have generated damaging earthquakes before and later. Some less common and moderate size earthquakes have occurred in the vicinity of the Marmara Islands in the west Marmara Sea. This paper presents an extended summary of the most important earthquakes that have occurred in 1265 and 1935 and have since been known as the Marmara Island earthquakes. The informative data and the approaches used have therefore the potential of documenting earthquake ruptures of fault segments and may extend the records kept on earthquakes far before known history, rock falls and abnormal sea waves observed during these events, thus improving hazard evaluations and the fundamental understanding of the process of an earthquake.

Investigating Earthquake-induced Landslides­a Historical Review

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

, extensive to relatively complete inventories landslides have been prepared for a relatively small number of earthquakes. Through the 1960's and 1970's the best landslide inventories typically were complete only for a central affected area, although the first virtually complete inventory of a large earthquake was prepared for the M 7.6 Guatemala earthquake in 1976. Beginning in 1980, virtu- ally complete landslide inventories have prepared for several additional earthquakes in California, El Salvador, Japan, Italy, and Taiwan. Most of these used aerial pho- tography in combination with ground field studies, although the studies of the most recent of these events, in Taiwan, have also used satellite imagery, and three of the others (including the two smallest) were compiled largely from ground-based field 1 studies without aerial photography. Since 1989, digital mapping and GIS techniques have come into common use for mapping earthquake-induced landslides, and the use of these techniques has greatly enhanced the level of analysis that can be applied to earthquake-induced landslide occurrence. The first synthesis of data on earthquake- induced landslides, completed in 1984, defined the general characteristics of these landslides, derived relations between landslide occurrence on the one hand and geo- logic and seismic parameters on the other hand, and identified the types of hazards as- sociated with them. Since then, additional synthesis of worldwide data (1999) and na- tional data from New Zealand (1997), Greece (2000), and Italy (2000) have provided additional data on landslide characteristics and hazards and have extended, revised, and refined these relations. Recently completed studies have also identified areas with anomalous landslide distributions, have provided data for correlating the occurrence of landslides with a measure of local ground motion, have verified the occasional delayed triggering of landslides as a consequence of seismic shaking, and have identi- fied

Posttraumatic stress disorder: a serious post-earthquake complication.

Science.gov (United States)

Farooqui, Mudassir; Quadri, Syed A; Suriya, Sajid S; Khan, Muhammad Adnan; Ovais, Muhammad; Sohail, Zohaib; Shoaib, Samra; Tohid, Hassaan; Hassan, Muhammad

2017-01-01

Earthquakes are unpredictable and devastating natural disasters. They can cause massive destruction and loss of life and survivors may suffer psychological symptoms of severe intensity. Our goal in this article is to review studies published in the last 20 years to compile what is known about posttraumatic stress disorder (PTSD) occurring after earthquakes. The review also describes other psychiatric complications that can be associated with earthquakes, to provide readers with better overall understanding, and discusses several sociodemographic factors that can be associated with post-earthquake PTSD. A search for literature was conducted on major databases such as MEDLINE, PubMed, EMBASE, and PsycINFO and in neurology and psychiatry journals, and many other medical journals. Terms used for electronic searches included, but were not limited to, posttraumatic stress disorder (PTSD), posttraumatic symptoms, anxiety, depression, major depressive disorder, earthquake, and natural disaster. The relevant information was then utilized to determine the relationships between earthquakes and posttraumatic stress symptoms. It was found that PTSD is the most commonly occurring mental health condition among earthquake survivors. Major depressive disorder, generalized anxiety disorder, obsessive compulsive disorder, social phobia, and specific phobias were also listed. The PTSD prevalence rate varied widely. It was dependent on multiple risk factors in target populations and also on the interval of time that had elapsed between the exposure to the deadly incident and measurement. Females seemed to be the most widely-affected group, while elderly people and young children exhibit considerable psychosocial impact.

Operational Earthquake Forecasting: Proposed Guidelines for Implementation (Invited)

Science.gov (United States)

Jordan, T. H.

2010-12-01

The goal of operational earthquake forecasting (OEF) is to provide the public with authoritative information about how seismic hazards are changing with time. During periods of high seismic activity, short-term earthquake forecasts based on empirical statistical models can attain nominal probability gains in excess of 100 relative to the long-term forecasts used in probabilistic seismic hazard analysis (PSHA). Prospective experiments are underway by the Collaboratory for the Study of Earthquake Predictability (CSEP) to evaluate the reliability and skill of these seismicity-based forecasts in a variety of tectonic environments. How such information should be used for civil protection is by no means clear, because even with hundredfold increases, the probabilities of large earthquakes typically remain small, rarely exceeding a few percent over forecasting intervals of days or weeks. Civil protection agencies have been understandably cautious in implementing formal procedures for OEF in this sort of “low-probability environment.” Nevertheless, the need to move more quickly towards OEF has been underscored by recent experiences, such as the 2009 L’Aquila earthquake sequence and other seismic crises in which an anxious public has been confused by informal, inconsistent earthquake forecasts. Whether scientists like it or not, rising public expectations for real-time information, accelerated by the use of social media, will require civil protection agencies to develop sources of authoritative information about the short-term earthquake probabilities. In this presentation, I will discuss guidelines for the implementation of OEF informed by my experience on the California Earthquake Prediction Evaluation Council, convened by CalEMA, and the International Commission on Earthquake Forecasting, convened by the Italian government following the L’Aquila disaster. (a) Public sources of information on short-term probabilities should be authoritative, scientific, open, and

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

Evaluating spatial and temporal relationships between an earthquake cluster near Entiat, central Washington, and the large December 1872 Entiat earthquake

Science.gov (United States)

Brocher, Thomas M.; Blakely, Richard J.; Sherrod, Brian

2017-01-01

We investigate spatial and temporal relations between an ongoing and prolific seismicity cluster in central Washington, near Entiat, and the 14 December 1872 Entiat earthquake, the largest historic crustal earthquake in Washington. A fault scarp produced by the 1872 earthquake lies within the Entiat cluster; the locations and areas of both the cluster and the estimated 1872 rupture surface are comparable. Seismic intensities and the 1–2 m of coseismic displacement suggest a magnitude range between 6.5 and 7.0 for the 1872 earthquake. Aftershock forecast models for (1) the first several hours following the 1872 earthquake, (2) the largest felt earthquakes from 1900 to 1974, and (3) the seismicity within the Entiat cluster from 1976 through 2016 are also consistent with this magnitude range. Based on this aftershock modeling, most of the current seismicity in the Entiat cluster could represent aftershocks of the 1872 earthquake. Other earthquakes, especially those with long recurrence intervals, have long‐lived aftershock sequences, including the Mw">MwMw 7.5 1891 Nobi earthquake in Japan, with aftershocks continuing 100 yrs after the mainshock. Although we do not rule out ongoing tectonic deformation in this region, a long‐lived aftershock sequence can account for these observations.

Orphans and at-risk children in Haiti: vulnerabilities and human rights issues postearthquake.

Science.gov (United States)

Nicholas, Patrice K; George, Erin K; Raymond, Nadia; Lewis-OʼConnor, Annie; Victoria, Stephanie; Lucien, Sergeline; Peters-Lewis, Angelleen; Hickey, Nancy; Corless, Inge B; Tyer-Viola, Lynda; Davis, Sheila M; Barry, Donna; Marcelin, Naomie; Valcourt, Roodeline

2012-01-01

The vulnerability of children in Haiti has increased dramatically since the earthquake in January 2010. Prior to the earthquake, the prevalence of orphans and at-risk children was high but since the earthquake, more than 1 million people-with more than 380,000 children remaining displaced and living in over 1200 displacement sites. These existing conditions leave orphans and at-risk children vulnerable to exploitation, abuse, and increased risk of HIV/AIDS. This article will focus on the complex issues affecting orphans and at-risk children and the intersection with HIV/AIDS and human rights. Specific recommendations by United Nations Children's Fund are discussed. Nursing in Haiti must address the policy-related and population-specific approaches for the care of children living with or affected by HIV/AIDS.

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

ELER software - a new tool for urban earthquake loss assessment

Science.gov (United States)

Hancilar, U.; Tuzun, C.; Yenidogan, C.; Erdik, M.

2010-12-01

Rapid loss estimation after potentially damaging earthquakes is critical for effective emergency response and public information. A methodology and software package, ELER-Earthquake Loss Estimation Routine, for rapid estimation of earthquake shaking and losses throughout the Euro-Mediterranean region was developed under the Joint Research Activity-3 (JRA3) of the EC FP6 Project entitled "Network of Research Infrastructures for European Seismology-NERIES". Recently, a new version (v2.0) of ELER software has been released. The multi-level methodology developed is capable of incorporating regional variability and uncertainty originating from ground motion predictions, fault finiteness, site modifications, inventory of physical and social elements subjected to earthquake hazard and the associated vulnerability relationships. Although primarily intended for quasi real-time estimation of earthquake shaking and losses, the routine is also equally capable of incorporating scenario-based earthquake loss assessments. This paper introduces the urban earthquake loss assessment module (Level 2) of the ELER software which makes use of the most detailed inventory databases of physical and social elements at risk in combination with the analytical vulnerability relationships and building damage-related casualty vulnerability models for the estimation of building damage and casualty distributions, respectively. Spectral capacity-based loss assessment methodology and its vital components are presented. The analysis methods of the Level 2 module, i.e. Capacity Spectrum Method (ATC-40, 1996), Modified Acceleration-Displacement Response Spectrum Method (FEMA 440, 2005), Reduction Factor Method (Fajfar, 2000) and Coefficient Method (ASCE 41-06, 2006), are applied to the selected building types for validation and verification purposes. The damage estimates are compared to the results obtained from the other studies available in the literature, i.e. SELENA v4.0 (Molina et al., 2008) and

A prospective earthquake forecast experiment in the western Pacific

Science.gov (United States)

Eberhard, David A. J.; Zechar, J. Douglas; Wiemer, Stefan

2012-09-01

Since the beginning of 2009, the Collaboratory for the Study of Earthquake Predictability (CSEP) has been conducting an earthquake forecast experiment in the western Pacific. This experiment is an extension of the Kagan-Jackson experiments begun 15 years earlier and is a prototype for future global earthquake predictability experiments. At the beginning of each year, seismicity models make a spatially gridded forecast of the number of Mw≥ 5.8 earthquakes expected in the next year. For the three participating statistical models, we analyse the first two years of this experiment. We use likelihood-based metrics to evaluate the consistency of the forecasts with the observed target earthquakes and we apply measures based on Student's t-test and the Wilcoxon signed-rank test to compare the forecasts. Overall, a simple smoothed seismicity model (TripleS) performs the best, but there are some exceptions that indicate continued experiments are vital to fully understand the stability of these models, the robustness of model selection and, more generally, earthquake predictability in this region. We also estimate uncertainties in our results that are caused by uncertainties in earthquake location and seismic moment. Our uncertainty estimates are relatively small and suggest that the evaluation metrics are relatively robust. Finally, we consider the implications of our results for a global earthquake forecast experiment.

The 2012 MW5.6 earthquake in the vicinity of the city of Sofia

Science.gov (United States)

Simeonova, Stela; Solakov, Dimcho; Aleksandrova, Irena; Dimitrova, Liliya; Popova, Iliana; Raykova, Plamena

2013-04-01

The territory of Bulgaria represents a typical example of high seismic risk area in the eastern part of the Balkan Peninsula. The neotectonic movements on the Balkan Peninsula were controlled by extensional collapse of the Late Alpin orogen, and were influenced by extension behind the Aegean arc and by the complicated vertical and horizontal movements in the Pannonian region. The city of Sofia is the capital of Bulgaria. It is situated in the centre of the Sofia seismic zone that is the most populated (more than 1.2 mil. inhabitants), industrial and cultural region of Bulgaria that faces considerable earthquake risk. Seismicity in the zone is related mainly to the marginal neotectonic faults of Sofia graben. The available historical documents prove the occurrence of destructive earthquakes during the 15th-18th centuries in the Sofia zone. In 19th century the city of Sofia has experienced two strong earthquakes: the 1818 earthquake with epicentral intensity I0=8-9 MSK and the 1858 earthquake with I0=IX-X MSK64. The 1858 earthquake caused heavy destruction in the town of Sofia and the appearance of thermal springs in the western part of the town. After a quiescence of about 50 years a strong event with M=6.5 occurred in 1905 near the western marginal part of the Sofia zone. During the 20th century the strongest event occurred in the vicinity of the city of Sofia is the 1917 earthquake with MS=5.3 (I0=7-8 MSK64). The earthquake caused a lot of damages in the town and changed the capacity of the thermal mineral springs in Sofia and the surrounding villages. The earthquake was felt in an area of 50000 km2 and followed by aftershocks, which lasted more than one year. Almost a century later (95 years) an earthquake of moment magnitude 5.6 hit Sofia seismic zone, on May 22nd, 2012, at 25 km south west of the city of Sofia. This shallow earthquake was largely felt in the region and up to Greece, FYROM, Serbia and Romania. No severe injuries have been reported so far, though

Shallow moonquakes - How they compare with earthquakes

Science.gov (United States)

Nakamura, Y.

1980-01-01

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

Automatic Earthquake Detection by Active Learning

Science.gov (United States)

Bergen, K.; Beroza, G. C.

2017-12-01

In recent years, advances in machine learning have transformed fields such as image recognition, natural language processing and recommender systems. Many of these performance gains have relied on the availability of large, labeled data sets to train high-accuracy models; labeled data sets are those for which each sample includes a target class label, such as waveforms tagged as either earthquakes or noise. Earthquake seismologists are increasingly leveraging machine learning and data mining techniques to detect and analyze weak earthquake signals in large seismic data sets. One of the challenges in applying machine learning to seismic data sets is the limited labeled data problem; learning algorithms need to be given examples of earthquake waveforms, but the number of known events, taken from earthquake catalogs, may be insufficient to build an accurate detector. Furthermore, earthquake catalogs are known to be incomplete, resulting in training data that may be biased towards larger events and contain inaccurate labels. This challenge is compounded by the class imbalance problem; the events of interest, earthquakes, are infrequent relative to noise in continuous data sets, and many learning algorithms perform poorly on rare classes. In this work, we investigate the use of active learning for automatic earthquake detection. Active learning is a type of semi-supervised machine learning that uses a human-in-the-loop approach to strategically supplement a small initial training set. The learning algorithm incorporates domain expertise through interaction between a human expert and the algorithm, with the algorithm actively posing queries to the user to improve detection performance. We demonstrate the potential of active machine learning to improve earthquake detection performance with limited available training data.

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

Economic consequences of earthquakes: bridging research and practice with HayWired

Science.gov (United States)

Wein, A. M.; Kroll, C.

2016-12-01

The U.S. Geological Survey partners with organizations and experts to develop multiple hazard scenarios. The HayWired earthquake scenario refers to a rupture of the Hayward fault in the Bay Area of California and addresses the potential chaos related to interconnectedness at many levels: the fault afterslip and aftershocks, interdependencies of lifelines, wired/wireless technology, communities at risk, and ripple effects throughout today's digital economy. The scenario is intended for diverse audiences. HayWired analyses translate earthquake hazards (surface rupture, ground shaking, liquefaction, landslides) into physical engineering and environmental health impacts, and into societal consequences. Damages to life and property and lifeline service disruptions are direct causes of business interruption. Economic models are used to estimate the economic impacts and resilience in the regional economy. The objective of the economic analysis is to inform policy discourse about economic resilience at all three levels of the economy: macro, meso, and micro. Stakeholders include businesses, economic development, and community leaders. Previous scenario analyses indicate the size of an event: large earthquakes and large winter storms are both "big ones" for California. They motivate actions to reduce the losses from fire following earthquake and water supply outages. They show the effect that resilience can have on reducing economic losses. Evaluators find that stakeholders learned the most about the economic consequences.

Prenatal Earthquake Exposure and Midlife Uric Acid Levels Among Chinese Adults.

Science.gov (United States)

Ji, Chunpeng; Li, Yanping; Cui, Liufu; Cai, Jianfang; Shi, Jihong; Cheng, Feon W; Li, Yuqing; Curhan, Gary C; Wu, Shouling; Gao, Xiang

2017-05-01

To test whether prenatal exposure to earthquake (as a surrogate for acute prenatal stress) could have unfavorable effects on uric acid levels later in life. We included 536 individuals who had been prenatally exposed to the Tangshan earthquake in 1976, and 536 sex- and age-matched individuals without that exposure. Serum uric acid concentrations were measured based on fasting blood samples, which were repeatedly collected in 2006, 2008, and 2010. Mean uric acid concentrations in 2010 and the increasing rate from 2006 to 2010 were compared between the 2 groups, after adjustment for age, sex, body mass index, serum concentrations of glucose, triglycerides, C-reactive protein level, estimated glomerular filtration rate, and other potential confounders. We also used multiple logistic regression to estimate the risk of hyperuricemia (>416 μmole/liter in men or >357 μmole/liter in women) in 2010 by calculating the odds ratios (ORs) and 95% confidence intervals (95% CIs) after adjustment for the previously mentioned covariates. Participants with prenatal exposure to the earthquake had higher concentrations of serum uric acid (adjusted means 315 μmole/liter versus 296 μmole/liter; P = 0.001) and a higher likelihood of having hyperuricemia (multivariate adjusted OR 1.70 [95% CI 1.09-2.66]) in 2010 relative to those without the exposure. Prenatal exposure to the earthquake was consistently significantly associated with a faster increase in uric acid concentration from 2006 to 2010 (P earthquake was associated with higher serum uric acid and higher odds of hyperuricemia in early adulthood. © 2016, American College of Rheumatology.

Decreasing Relative Risk Premium

DEFF Research Database (Denmark)

Hansen, Frank

relative risk premium in the small implies decreasing relative risk premium in the large, and decreasing relative risk premium everywhere implies risk aversion. We finally show that preferences with decreasing relative risk premium may be equivalently expressed in terms of certain preferences on risky......We consider the risk premium demanded by a decision maker with wealth x in order to be indifferent between obtaining a new level of wealth y1 with certainty, or to participate in a lottery which either results in unchanged present wealth or a level of wealth y2 > y1. We define the relative risk...... premium as the quotient between the risk premium and the increase in wealth y1–x which the decision maker puts on the line by choosing the lottery in place of receiving y1 with certainty. We study preferences such that the relative risk premium is a decreasing function of present wealth, and we determine...

Tilt Precursors before Earthquakes on the San Andreas Fault, California.

Science.gov (United States)

Johnston, M J; Mortensen, C E

1974-12-13

An array of 14 biaxial shallow-borehole tiltmeters (at 1O(-7) radian sensitivity) has been installed along 85 kilometers of the San Andreas fault during the past year. Earthquake-related changes in tilt have been simultaneously observed on up to four independent instruments. At earthquake distances greater than 10 earthquake source dimensions, there are few clear indications of tilt change. For the four instruments with the longest records (> 10 months), 26 earthquakes have occurred since July 1973 with at least one instrument closer than 10 source dimensions and 8 earthquakes with more than one instrument within that distance. Precursors in tilt direction have been observed before more than 10 earthquakes or groups of earthquakes, and no similar effect has yet been seen without the occurrence of an earthquake.

Seismic hazard and seismic risk assessment based on the unified scaling law for earthquakes: Himalayas and adjacent regions

Science.gov (United States)

Nekrasova, A. K.; Kossobokov, V. G.; Parvez, I. A.

2015-03-01

For the Himalayas and neighboring regions, the maps of seismic hazard and seismic risk are constructed with the use of the estimates for the parameters of the unified scaling law for earthquakes (USLE), in which the Gutenberg-Richter law for magnitude distribution of seismic events within a given area is applied in the modified version with allowance for linear dimensions of the area, namely, log N( M, L) = A + B (5 - M) + C log L, where N( M, L) is the expected annual number of the earthquakes with magnitude M in the area with linear dimension L. The spatial variations in the parameters A, B, and C for the Himalayas and adjacent regions are studied on two time intervals from 1965 to 2011 and from 1980 to 2011. The difference in A, B, and C between these two time intervals indicates that seismic activity experiences significant variations on a scale of a few decades. With a global consideration of the seismic belts of the Earth overall, the estimates of coefficient A, which determines the logarithm of the annual average frequency of the earthquakes with a magnitude of 5.0 and higher in the zone with a linear dimension of 1 degree of the Earth's meridian, differ by a factor of 30 and more and mainly fall in the interval from -1.1 to 0.5. The values of coefficient B, which describes the balance between the number of earthquakes with different magnitudes, gravitate to 0.9 and range from less than 0.6 to 1.1 and higher. The values of coefficient C, which estimates the fractal dimension of the local distribution of epicenters, vary from 0.5 to 1.4 and higher. In the Himalayas and neighboring regions, the USLE coefficients mainly fall in the intervals of -1.1 to 0.3 for A, 0.8 to 1.3 for B, and 1.0 to 1.4 for C. The calculations of the local value of the expected peak ground acceleration (PGA) from the maximal expected magnitude provided the necessary basis for mapping the seismic hazards in the studied region. When doing this, we used the local estimates of the

Turning the rumor of May 11, 2011 earthquake prediction In Rome, Italy, into an information day on earthquake hazard

Science.gov (United States)

Amato, A.; Cultrera, G.; Margheriti, L.; Nostro, C.; Selvaggi, G.; INGVterremoti Team

2011-12-01

A devastating earthquake had been predicted for May 11, 2011 in Rome. This prediction was never released officially by anyone, but it grew up in the Internet and was amplified by media. It was erroneously ascribed to Raffaele Bendandi, an Italian self-taught natural scientist who studied planetary motions. Indeed, around May 11, 2011, a planetary alignment was really expected and this contributed to give credibility to the earthquake prediction among people. During the previous months, INGV was overwhelmed with requests for information about this supposed prediction by Roman inhabitants and tourists. Given the considerable mediatic impact of this expected earthquake, INGV decided to organize an Open Day in its headquarter in Rome for people who wanted to learn more about the Italian seismicity and the earthquake as natural phenomenon. The Open Day was preceded by a press conference two days before, in which we talked about this prediction, we presented the Open Day, and we had a scientific discussion with journalists about the earthquake prediction and more in general on the real problem of seismic risk in Italy. About 40 journalists from newspapers, local and national tv's, press agencies and web news attended the Press Conference and hundreds of articles appeared in the following days, advertising the 11 May Open Day. The INGV opened to the public all day long (9am - 9pm) with the following program: i) meetings with INGV researchers to discuss scientific issues; ii) visits to the seismic monitoring room, open 24h/7 all year; iii) guided tours through interactive exhibitions on earthquakes and Earth's deep structure; iv) lectures on general topics from the social impact of rumors to seismic risk reduction; v) 13 new videos on channel YouTube.com/INGVterremoti to explain the earthquake process and give updates on various aspects of seismic monitoring in Italy; vi) distribution of books and brochures. Surprisingly, more than 3000 visitors came to visit INGV

Source study of the Jan Mayen transform fault strike-slip earthquakes

Science.gov (United States)

Rodríguez-Pérez, Q.; Ottemöller, L.

2014-07-01

Seismic source parameters of oceanic transform zone earthquakes have been relatively poorly studied. Previous studies showed that this type of earthquakes has unique characteristics such as not only the relatively common occurrence of slow events with weak seismic radiation at high frequencies but also the occurrence of some events that have high apparent stress indicating strong high frequency radiation. We studied 5 strike-slip earthquakes in the Jan Mayen fracture zone with magnitudes in the range of 5.9 centroid time delay compared to other oceanic transform fault earthquakes.

Development of a national system for prevention and mitigation of earthquake damages to people and properties, and the reduction of costs related to earthquakes for the Italian Government

Science.gov (United States)

Console, R.; Greco, M.; Colangelo, A.; Cioè, A.; Trivigno, L.; Chiappini, M.; Ponzo, F.

2015-12-01

Recognizing that the Italian territory is prone to disasters in connection with seismic and hydro-geological risk, it has become necessary to define novel regulations and viable solutions aimed at conveying the economical resources of the Italian Government, too often utilized for the management of post-event situations, towards prevention activities. The work synthetically presents the project developed by the CGIAM together with the INGV, and open to collaboration with other Italian and International partners. This project is aimed at the development of a National System for prevention and mitigation of the earthquakes damages, through the definition of a model that achieves the mitigation of the building collapsing risk and the consequent reduction of casualties. Such a model is based on two main issues a) a correct evaluation of risk, defined as a reliable assessment of the hazard expected at a given site and of the vulnerability of civil and industrial buildings, b) setting up of novel strategies for the safety of buildings. The hazard assessment is pursued through the application of innovative multidisciplinary geophysical methodologies and the application of a physically based earthquake simulator. The structural vulnerability of buildings is estimated by means of simplified techniques based on few representative parameters (such as different structural typologies, dynamic soil-structure interaction, etc.) and, for detailed studies, standard protocols for model updating techniques. We analyze, through numerical and experimental approaches, new solutions for the use of innovative materials, and new techniques for the reduction of seismic vulnerability of structural, non-structural and accessorial elements, including low cost type. The project activities are initially implemented on a study area in Southern Italy (Calabria) selected because of its tectonic complexity. The results are expected to be applicable for other hazardous seismic areas of Italy.

A smartphone application for earthquakes that matter!

Science.gov (United States)

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

2014-05-01

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

Investigation of tectonics and statistical analysis of earthquake hazard in Tange Sorkh dam

OpenAIRE

ZOLFAGHARI, Sayyed Yaghoub; RAFIEE, A.; HADI, S. M.R.; TAHERMANESH, R.

2015-01-01

Abstract. Today, most understood the importance of the risk of earthquakes with the intensification of the country's development, the rise in urbanization, the concentration of population and material and intellectual capital and increased vulnerability of the capital in the Iran seismic zone. Iran, as one of the most seismic countries in the world, in recent years has witnessed the devastating earthquake, for example can be pointed to earthquakes of Rudbar - Manjil, Bojnoord, Zir Kouh Ghaena...

Regional earthquake loss estimation in the Autonomous Province of Bolzano - South Tyrol (Italy)

Science.gov (United States)

Huttenlau, Matthias; Winter, Benjamin

2013-04-01

Beside storm events geophysical events cause a majority of natural hazard losses on a global scale. However, in alpine regions with a moderate earthquake risk potential like in the study area and thereupon connected consequences on the collective memory this source of risk is often neglected in contrast to gravitational and hydrological hazards processes. In this context, the comparative analysis of potential disasters and emergencies on a national level in Switzerland (Katarisk study) has shown that earthquakes are the most serious source of risk in general. In order to estimate the potential losses of earthquake events for different return periods and loss dimensions of extreme events the following study was conducted in the Autonomous Province of Bolzano - South Tyrol (Italy). The applied methodology follows the generally accepted risk concept based on the risk components hazard, elements at risk and vulnerability, whereby risk is not defined holistically (direct, indirect, tangible and intangible) but with the risk category losses on buildings and inventory as a general risk proxy. The hazard analysis is based on a regional macroseismic scenario approach. Thereby, the settlement centre of each community (116 communities) is defined as potential epicentre. For each epicentre four different epicentral scenarios (return periods of 98, 475, 975 and 2475 years) are calculated based on the simple but approved and generally accepted attenuation law according to Sponheuer (1960). The relevant input parameters to calculate the epicentral scenarios are (i) the macroseismic intensity and (ii) the focal depth. The considered macroseismic intensities are based on a probabilistic seismic hazard analysis (PSHA) of the Italian earthquake catalogue on a community level (Dipartimento della Protezione Civile). The relevant focal depth are considered as a mean within a defined buffer of the focal depths of the harmonized earthquake catalogues of Italy and Switzerland as well as

Electrocardiographic features of patients with earthquake related posttraumatic stress disorder

OpenAIRE

İlhan, Erkan; Kaplan, Abdullah; Güvenç, Tolga Sinan; Biteker, Murat; Karabulut, Evindar; Işıklı, Serhan

2013-01-01

AIM: To analyze electrocardiographic features of patients diagnosed with posttraumatic stress disorder (PTSD) after the Van-Erciş earthquake, with a shock measuring 7.2 on the Richter scale that took place in Turkey in October 2011.

Accelerating risk reduction in Kathmandu Valley, Nepal: Theory-based mass-media intervention proven to increase knowledge of, belief in, and intent to support earthquake-resistant construction.

Science.gov (United States)

Sanquini, A.; Thapaliya, S. M.; Wood, M. M.; Hilley, G. E.

2015-12-01

Motivating people in rapidly urbanizing areas to take protective actions against natural disasters faces the challenge that these people often do not know what actions to take, do not believe that such actions are effective, and/or believe that the disaster will not happen to them within their lifetimes. Thus, finding demonstrated ways of motivating people to take protective action likely constitutes a grand challenge for natural disaster risk reduction and resiliency, because it may be one of the largest, lowest-cost sources of potential risk reduction in these situations. We developed a theory-based documentary film (hereafter, intervention) targeted at motivating retrofits of local school buildings, and tested its effectiveness in Kathmandu, Nepal, using a matched-pair clustered randomized controlled trial. The intervention features Nepalese who have strengthened their school buildings as role models to others at schools still in need of seismic work. It was tested at 16 Kathmandu Valley schools from November 2014 through March 2015. Schools were matched into 8 pairs, then randomly assigned to see either the intervention film or an attention placebo control film on an unrelated topic. Testing was completed just five weeks before the M 7.8 Gorkha earthquake struck central Nepal. When compared to the control schools, the schools whose community members saw the retrofit intervention film increased their knowledge of specific actions to take in support of earthquake-resistant construction, belief in the feasibility of making buildings earthquake-resistant, willingness to support seismic strengthening of the local school building, and likelihood to recommend to others that they build earthquake-resistant homes, which have all been shown to be precursors to taking self-protective action. This suggests that employing a mass-media intervention featuring community members who have already taken the desired action increases factors that may accelerate adoption of risk

Earthquake, GIS and multimedia. The 1883 Casamicciola earthquake

Directory of Open Access Journals (Sweden)

M. Rebuffat

1995-06-01

Full Text Available A series of multimedia monographs concerning the main seismic events that have affected the Italian territory are in the process of being produced for the Documental Integrated Multimedia Project (DIMP started by the Italian National Seismic Survey (NSS. The purpose of the project is to reconstruct the historical record of earthquakes and promote an earthquake public education. Producing the monographs. developed in ARC INFO and working in UNIX. involved designing a special filing and management methodology to integrate heterogeneous information (images, papers, cartographies, etc.. This paper describes the possibilities of a GIS (Geographic Information System in the filing and management of documental information. As an example we present the first monograph on the 1883 Casamicciola earthquake. on the island of Ischia (Campania, Italy. This earthquake is particularly interesting for the following reasons: I historical-cultural context (first destructive seismic event after the unification of Italy; 2 its features (volcanic earthquake; 3 the socioeconomic consequences caused at such an important seaside resort.