Articles | Volume 19, issue 10
Research article 01 Oct 2019
Research article | 01 Oct 2019
Probabilistic seismic hazard analysis using the logic tree approach – Patna district (India)
Panjamani Anbazhagan et al.
No articles found.
Mikhail K. Kaban, Sami El Khrepy, and Nassir Al-Arifi
Solid Earth, 9, 833–846,Short summary
We present an integrative model of the crust and upper mantle of Egypt based on an analysis of gravity, seismic, and geological data. These results are essential for deciphering the link between the dynamic processes in the Earth system and near-surface processes (particularly earthquakes) that influence human habitat. We identified the distinct fragmentation of the lithosphere of Egypt in several blocks. This division is closely related to the seismicity patterns in this region.
Sami El Khrepy, Ivan Koulakov, Nassir Al-Arifi, and Alexey G. Petrunin
Solid Earth, 7, 965–978,Short summary
Three-dimensional seismic structures beneath the Gulf of Aqaba are presented for the first time for the southern part of the Dead Sea. A regional earthquake tomography method is applied to P and S waves data. The new results indicate new perspectives suggesting an oceanic nature of the crust in the northern part of the Red Sea, disagreeing with the hypothesis of a gradual stretching of the continental crust.
I. Koulakov, A. Jakovlev, I. Zabelina, F. Roure, S. Cloetingh, S. El Khrepy, and N. Al-Arifi
Solid Earth, 6, 669–679,Short summary
A new regional seismic tomography model of the upper mantle beneath Italy is presented. Here we identify a high-velocity anomaly, identifiable as a long, narrow sausage-shaped body with a steeply dipping part down to a depth of 400km and then expanding horizontally over ~400km. We propose that it could be made up of infra continental lithospheric mantle of Adria, which is progressively delaminated, whereas its overlying crust becomes progressively accreted into the Apenninic tectonic wedge.
I. Koulakov, S. El Khrepy, N. Al-Arifi, I. Sychev, and P. Kuznetsov
Solid Earth, 5, 873–882,
Related subject area
Earthquake HazardsFault network reconstruction using agglomerative clustering: applications to southern Californian seismicityStyle of faulting of expected earthquakes in Italy as an input for seismic hazard modelingThe utility of earth science information in post-earthquake land-use decision-making: the 2010–2011 Canterbury earthquake sequence in Aotearoa New ZealandSpatiotemporal changes of seismicity rate during earthquakesDeep learning of the aftershock hysteresis effect based on the elastic dislocation theoryMeasuring the seismic risk along the Nazca–South American subduction front: Shannon entropy and mutabilityMacrozonation of seismic transient and permanent ground deformation of IranSpatial database and website for reservoir-triggered seismicity in BrazilProbabilistic tsunami hazard analysis for Tuzla test site using Monte Carlo simulationsSeismic hazard maps of Peshawar District for various return periodsContrasting seismic risk for Santiago, Chile, from near-field and distant earthquake sourcesThe spatial–temporal total friction coefficient of the fault viewed from the perspective of seismo-electromagnetic theoryReliability-based strength modification factor for seismic design spectra considering structural degradationNon-stationary extreme value analysis applied to seismic fragility assessment for nuclear safety analysisReal-time probabilistic seismic hazard assessment based on seismicity anomalyThe impact of topography on seismic amplification during the 2005 Kashmir earthquakeAssessment of seismic sources and capable faults through hierarchic tectonic criteria: implications for seismic hazard in the LevantAnalysis of spatiotemporal variations in middle-tropospheric to upper-tropospheric methane during the Wenchuan Ms = 8.0 earthquake by three indicesInfrasound and seismoacoustic signatures of the 28 September 2018 Sulawesi super-shear earthquakeEstimation of near-surface attenuation in the tectonically complex contact area of the northwestern External Dinarides and the Adriatic forelandDifficulties in explaining complex issues with maps: evaluating seismic hazard communication – the Swiss caseGeologic and geomorphic controls on rockfall hazard: how well do past rockfalls predict future distributions?A review and upgrade of the lithospheric dynamics in context of the seismo-electromagnetic theoryRevised earthquake sources along Manila trench for tsunami hazard assessment in the South China SeaFrom rapid visual survey to multi-hazard risk prioritisation and numerical fragility of school buildingsTaylor's power law in the Wenchuan earthquake sequence with fluctuation scalingDamage induced by the 25 April 2015 Nepal earthquake in the Tibetan border region of China and increased post-seismic hazardsEvaluating earthquake-induced rockfall hazard near the Dead Sea TransformA statistical analysis of TIR anomalies extracted by RSTs in relation to an earthquake in the Sichuan area using MODIS LST dataIndirect seismic economic loss assessment and recovery evaluation using nighttime light images – application for Wenchuan earthquakeActive faults sources for the Pátzcuaro–Acambay fault system (Mexico): fractal analysis of slip rates and magnitudes Mw estimated from fault lengthApproach for combining fault and area sources in seismic hazard assessment: application in south-eastern SpainRevisiting seismic hazard assessment for Peninsular Malaysia using deterministic and probabilistic approachesMulti-hazard fragility analysis for fluvial dikes in earthquake- and flood-prone areasA study of earthquake recurrence based on a one-body spring-slider model in the presence of thermal-pressurized slip-weakening friction and viscosityAnalysis of the disaster characteristics and emergency response of the Jiuzhaigou earthquakeEarthquakes on the surface: earthquake location and area based on more than 14 500 ShakeMapsAssessment of liquefaction-induced hazards using Bayesian networks based on standard penetration test dataPre-seismic anomalies from optical satellite observations: a reviewDamage during the 6–24 February 2017 Ayvacık (Çanakkale) earthquake swarmMāori oral histories and the impact of tsunamis in Aotearoa-New ZealandImplications from palaeoseismological investigations at the Markgrafneusiedl Fault (Vienna Basin, Austria) for seismic hazard assessmentThe effect of alternative seismotectonic models on PSHA results – a sensitivity study for two sites in IsraelWidth of surface rupture zone for thrust earthquakes: implications for earthquake fault zoningSeismic assessment of a multi-span steel railway bridge in Turkey based on nonlinear time historyDetection of collapsed buildings from lidar data due to the 2016 Kumamoto earthquake in JapanPlanar seismic source characterization models developed for probabilistic seismic hazard assessment of IstanbulIntegrating faults and past earthquakes into a probabilistic seismic hazard model for peninsular ItalyWhen probabilistic seismic hazard climbs volcanoes: the Mt. Etna case, Italy – Part 2: Computational implementation and first resultsWhen probabilistic seismic hazard climbs volcanoes: the Mt. Etna case, Italy – Part 1: Model components for sources parameterization
Yavor Kamer, Guy Ouillon, and Didier Sornette
Nat. Hazards Earth Syst. Sci., 20, 3611–3625,Short summary
Earthquakes cluster in space highlighting fault structures in the crust. We introduce a method to identify such patterns. The method follows a bottom-up approach that starts from many small clusters and, by repeated mergings, produces a larger, less complex structure. We test the resulting fault network model by investigating its ability to forecast the location of earthquakes that were not used in the study. We envision that our method can contribute to future studies relying on fault patterns.
Silvia Pondrelli, Francesco Visini, Andrea Rovida, Vera D'Amico, Bruno Pace, and Carlo Meletti
Nat. Hazards Earth Syst. Sci., 20, 3577–3592,Short summary
We used 100 years of seismicity in Italy to predict the hypothetical tectonic style of future earthquakes, with the purpose of using this information in a new seismic hazard model. To squeeze all possible information out of the available data, we created a chain of criteria to be applied in the input and output selection processes. The result is a list of cases from very clear ones, e.g., extensional tectonics in the central Apennines, to completely random tectonics for future seismic events.
Mark C. Quigley, Wendy Saunders, Chris Massey, Russ Van Dissen, Pilar Villamor, Helen Jack, and Nicola Litchfield
Nat. Hazards Earth Syst. Sci., 20, 3361–3385,Short summary
This paper examines the roles of earth science information (data, knowledge, advice) in land-use decision-making in Christchurch, New Zealand, in response to the 2010–2011 Canterbury earthquake sequence. A detailed timeline of scientific activities and information provisions relative to key decision-making events is provided. We highlight the importance and challenges of the effective provision of science to decision makers in times of crisis.
Chieh-Hung Chen, Yang-Yi Sun, Strong Wen, Peng Han, Li-Ching Lin, Huaizhong Yu, Xuemin Zhang, Yongxin Gao, Chi-Chia Tang, Cheng-Horng Lin, and Jann-Yenq Liu
Nat. Hazards Earth Syst. Sci., 20, 3333–3341,Short summary
Scientists demystify stress changes before mainshocks and utilize the foreshocks as an indicator. We investigate changes in seismicity far from mainshocks by using tens of thousands of M ≥ 2 quakes for 10 years in Taiwan and Japan. The results show that wide areas exhibit increased seismicity occurring more than several times in areas of the fault rupture. The stressed crust triggers resonance at frequencies varying from ~ 5 × 10–4 to ~ 10–3 Hz that is supported by the resonant frequency model.
Jin Chen, Hong Tang, and Wenkai Chen
Nat. Hazards Earth Syst. Sci., 20, 3117–3134,Short summary
The spatial and temporal distribution characteristics of aftershocks around the fault are analyzed according to the stress changes after the main earthquake. The model can be used to predict the multi-timescale anisotropy distribution of aftershocks fairly. The finite fault model of the main earthquake is used in the construction of the prediction model. The model is a deep neural network; the inputs are the stress components of each point; and the output is the probability of an aftershock.
Eugenio E. Vogel, Felipe G. Brevis, Denisse Pastén, Víctor Muñoz, Rodrigo A. Miranda, and Abraham C.-L. Chian
Nat. Hazards Earth Syst. Sci., 20, 2943–2960,Short summary
The Nazca–South American subduction front is one of the most active in the world. We have chosen four zones along this front to do a comparative study on possible different dynamics. Data are public and well tested in the last decades. The methods are original since mutability and Shannon entropy are not always used in this kind of problem, and, to our knowledge, this is the first time they are combined. The north of Chile could be a zone with greater chances of a large earthquake.
Saeideh Farahani, Behrouz Behnam, and Ahmad Tahershamsi
Nat. Hazards Earth Syst. Sci., 20, 2889–2903,Short summary
Iran is located on the Alpide earthquake belt, in the active collision zone between the Eurasian and Arabian plates. Due to the rapid demands for new lifelines, a risk assessment should be performed to reduce the probable damage in advance. In this study, a precise GIS-based map is proposed by employing the HAZUS methodology.
Eveline Sayão, George Sand França, Maristela Holanda, and Alexandro Gonçalves
Nat. Hazards Earth Syst. Sci., 20, 2001–2019,Short summary
One of the biggest challenges in studying reservoir-triggered seismicity (RTS) is to identify factors that can trigger seismicity. A spatial database and a web viewer were created, gathering the data pertinent to the RTS study. Results were obtained in processing these data; for example, the occurrence of RTS increases with the height of the dam, the minimum limiting volume value is 1 × 10−4 km3 for occurrence of RTS, and for geology no correlations were found, among other results.
Hafize Basak Bayraktar and Ceren Ozer Sozdinler
Nat. Hazards Earth Syst. Sci., 20, 1741–1764,Short summary
In this study, probabilistic tsunami hazard analysis was performed for the Tuzla region in case of a Prince Island fault rupture, which is the closest fault zone to the megacity Istanbul, and it has been silent for centuries. A synthetic earthquake catalog is generated using Monte Carlo simulations, and these events are used for tsunami analysis. The results of the study show that the probability of exceedance of 0.3 m tsunami wave height is bigger than 90 % for the next 50 and 100 years.
Khalid Mahmood, Naveed Ahmad, Usman Khan, and Qaiser Iqbal
Nat. Hazards Earth Syst. Sci., 20, 1639–1661,Short summary
The paper presents probabilistic-based seismic hazard maps prepared for Peshawar for various return periods using classical PSHA. The study considered both shallow and deep earthquakes, represented by area sources, while using recent ground motion prediction equations. The hazard map for a 475-year return period was compared with the hazard map given in the Building Code of Pakistan; they were found to be in close agreement. The obtained maps may be used for infrastructure risk assessment.
Ekbal Hussain, John R. Elliott, Vitor Silva, Mabé Vilar-Vega, and Deborah Kane
Nat. Hazards Earth Syst. Sci., 20, 1533–1555,Short summary
Many of the rapidly expanding cities around the world are located near active tectonic faults that have not produced an earthquake in recent memory. But these faults are generally small, and so most previous seismic-hazard analysis has focussed on large, more distant faults. In this paper we show that a moderate-size earthquake on a fault close to the city of Santiago in Chile has a greater impact on the city than a great earthquake on the tectonic boundary in the ocean, about a 100 km away.
Patricio Venegas-Aravena, Enrique G. Cordaro, and David Laroze
Nat. Hazards Earth Syst. Sci., 20, 1485–1496,Short summary
Over the past few years, a number of data have emerged on predicting large earthquakes using the magnetic field. These measurements are becoming strongly supported by rock electrification mechanisms experimentally and theoretically in seismo-electromagnetic theory. However, the processes that occur within the faults have yet to be elucidated. That is why this work theoretically links the friction changes of the faults with the lithospheric magnetic anomalies that surround the faults.
Sonia E. Ruiz, Ali Rodríguez-Castellanos, Edén Bojórquez, Miguel A. Orellana, and Afredo Reyes-Salazar
Nat. Hazards Earth Syst. Sci. Discuss.,
Revised manuscript accepted for NHESSShort summary
Seismic design guidelines for building structures present simplified approaches to include relevant structural behavior that affects the structural response through design-spectra modification factors. The objective of this study is to propose simplified mathematical expressions to modify the design-spectra to consider the stiffness and strength degrading behavior of structures. Additionally, these expressions are proposed to be included in the next version of the Mexico City Building Code.
Jeremy Rohmer, Pierre Gehl, Marine Marcilhac-Fradin, Yves Guigueno, Nadia Rahni, and Julien Clément
Nat. Hazards Earth Syst. Sci., 20, 1267–1285,Short summary
Fragility curves (FCs) are key tools for seismic probabilistic safety assessments that are performed at the level of the nuclear power plant (NPP). These statistical methods relate the probabilistic seismic hazard loading at the given site to the required performance of the NPP safety functions. In the present study, we investigate how the tools of non-stationary extreme value analysis can be used to model in a flexible manner the FCs for NPP.
Yu-Sheng Sun, Hsien-Chi Li, Ling-Yun Chang, Zheng-Kai Ye, and Chien-Chih Chen
Nat. Hazards Earth Syst. Sci., 20, 743–753,Short summary
Real-time probabilistic seismic hazard assessment (PSHA) was developed in consideration of its practicability for daily life and the rate of seismic activity with time. We selected the 2016 Meinong (ML 6.6) and the 2018 Hualien (ML 6.2) earthquakes in Taiwan as examples. The seismic intensity forecasting maps produced by the real-time PSHA facilitated the forecast of the maximum expected seismic intensity for the following 90 d. Compared with real data the maps showed considerable effectiveness.
Saad Khan, Mark van der Meijde, Harald van der Werff, and Muhammad Shafique
Nat. Hazards Earth Syst. Sci., 20, 399–411,Short summary
On 8 October 2005 the region of Kashmir was struck by a devastating earthquake of magnitude 7.6. Northern Pakistan and the region of Kashmir were severely damaged. The official death toll according to the Pakistani government was 87 350. It was thought that the terrain could have played a crucial role in the damage caused by the earthquake directly or indirectly. In this article we found that the terrain played a crucial role in intensifying the devastation of the earthquake.
Matty Sharon, Amir Sagy, Ittai Kurzon, Shmuel Marco, and Marcelo Rosensaft
Nat. Hazards Earth Syst. Sci., 20, 125–148,Short summary
We present a methodology for mapping faults that constitute far-field (ground motion) and near-field (surface rupture) hazards to structures, particularly for critical facilities. For categorising faults, the criteria are adjusted to local tectonic characteristics, combining data of geological maps, instrumental seismicity, geodesy and past earthquakes. Our results adhere to international standards of hazard assessment for nuclear power plants and improve the regional tectonic understanding.
Jing Cui, Xuhui Shen, Jingfa Zhang, Weiyu Ma, and Wei Chu
Nat. Hazards Earth Syst. Sci., 19, 2841–2854,
Christoph Pilger, Peter Gaebler, Lars Ceranna, Alexis Le Pichon, Julien Vergoz, Anna Perttu, Dorianne Tailpied, and Benoit Taisne
Nat. Hazards Earth Syst. Sci., 19, 2811–2825,Short summary
This paper provides infrasound data analysis, modeling, and interpretation of the source characteristics of the 28 September 2018 magnitude 7.5 Sulawesi earthquake. Epicentral ground movement by the earthquake rupture as well as the secondary shaking of nearby mountainous topography is responsible for the strong infrasound generated. Findings allow one to improve knowledge of infrasonic and seismoacoustic source processes and the monitoring capabilities of the infrasound arrays used.
Snježana Markušić, Davor Stanko, Tvrtko Korbar, and Ivica Sović
Nat. Hazards Earth Syst. Sci., 19, 2701–2714,Short summary
Based on κ values, estimated from local earthquakes recorded by seismological stations situated in the western part of Croatia, regional near-surface attenuation is defined. It shows that attenuation properties of rocks in the northwestern External Dinarides are far from isotropic. The most likely anisotropy sources are the preferential orientations of cracks and fractures under the local tectonic stress field, trapping of waves along major faults, and/or attenuation within the fault zones.
Michèle Marti, Michael Stauffacher, and Stefan Wiemer
Nat. Hazards Earth Syst. Sci., 19, 2677–2700,Short summary
Maps are an established way to illustrate natural hazards and regularly used to communicate with non-experts. However, there is evidence that they are frequently misconceived. Using a real case, our study shows that applying or disregarding best practices in visualization, editing, and presentation significantly impacts the comprehensibility of seismic hazard information. We suggest scrutinizing current natural-hazard communication strategies and empirically testing new products.
Josh Borella, Mark Quigley, Zoe Krauss, Krystina Lincoln, Januka Attanayake, Laura Stamp, Henry Lanman, Stephanie Levine, Sam Hampton, and Darren Gravley
Nat. Hazards Earth Syst. Sci., 19, 2249–2280,Short summary
Here we evaluate geologic, geomorphic, and anthropogenic controls on rockfall hazard and highlight the complexity of interpreting future rockfall hazard based on former boulder distributions. To evaluate how past rockfall deposits relate to contemporary rockfall hazard, we mapped then compared the locations, physical characteristics, and lithologies of rockfall boulders deposited during the 2010–2011 Canterbury earthquake sequence (n = 185) with their prehistoric counterparts (n = 1093).
Patricio Venegas-Aravena, Enrique G. Cordaro, and David Laroze
Nat. Hazards Earth Syst. Sci., 19, 1639–1651,Short summary
Several authors have shown evidence of electromagnetic measurements prior to earthquakes. However, these investigations lack a physical mechanism to support them. That is why we developed a theory that could explain many of these phenomena. Specifically, we demonstrate that the generation of microcracks in the lithosphere due to stress changes can explain and describe these electromagnetic phenomena.
Qiang Qiu, Linlin Li, Ya-Ju Hsu, Yu Wang, Chung-Han Chan, and Adam D. Switzer
Nat. Hazards Earth Syst. Sci., 19, 1565–1583,Short summary
The accuracy of tsunami hazard assessments is highly dependent on the reliability of earthquake source models. In this study, we combine the most updated geological and geophysical data of the Manila subduction zone to propose a series of possible rupture scenarios. These rupture models facilitate an improved understanding of the potential tsunami hazard in the South China Sea. The results highlight the grave consequences faced by the SCS, one of the world's most densely populated coastlines.
Roberto Gentile, Carmine Galasso, Yunita Idris, Ibnu Rusydy, and Ella Meilianda
Nat. Hazards Earth Syst. Sci., 19, 1365–1386,Short summary
This paper introduces the INSPIRE index, which quantifies the relative seismic risk of reinforced concrete buildings. A rapid visual survey form is proposed, which allows us to (1) calculate the INSPIRE index, (2) calculate a tsunami risk index, and (3) define archetype buildings to be analysed in more detail. The effectiveness of such tools is demonstrated with an application to 85 school buildings in Indonesia, also providing detailed numerical simulations for an archetype building.
Peijian Shi, Mei Li, Yang Li, Jie Liu, Haixia Shi, Tao Xie, and Chong Yue
Nat. Hazards Earth Syst. Sci., 19, 1119–1127,Short summary
A statistical method is tentatively utilized to study distribution properties of aftershocks of the Wenchuan sequence in the view of energy release. The results show that the events in the Wenchuan sequence are not independent but have mutual attraction, their spatio–temporal distribution tends to be nonrandom but definite and deterministic, and imply it is possible for energy release to be predicted, although we cannot accurately predict the occurrence time and locations of the imminent event.
Zhonghai Wu, Patrick J. Barosh, Guanghao Ha, Xin Yao, Yongqiang Xu, and Jie Liu
Nat. Hazards Earth Syst. Sci., 19, 873–888,Short summary
The main damage characteristics have been reported in Nepal caused by the 2015 Nepal earthquake but not in China. Our investigations suggested that damage caused by the earthquake in Tibet varies with intensity, amount of rock weakened by previous movement, steepness of slope, and lithology. The damage shows directional features mainly developed in the N-trending rifts in southern Tibet. The earthquake-induced landslides and collapses generally occurred where previous ones had taken place.
Mor Kanari, Oded Katz, Ram Weinberger, Naomi Porat, and Shmuel Marco
Nat. Hazards Earth Syst. Sci., 19, 889–906,Short summary
We study rockfall hazard to a town in an earthquake-prone area, where large trailer-truck-sized boulders are scattered downslope above the town. Mapping boulder locations and sizes (in the field and in past aerial photos) and calculating their predicted trajectories downslope using computer simulation yielded a hazard map for rockfall impact. Hazard is reduced where slope angle is below 10°. Dating rockfalls coincides with past earthquakes and predicts probability for future rockfall.
Ying Zhang and Qingyan Meng
Nat. Hazards Earth Syst. Sci., 19, 535–549,Short summary
There is a long history of researching earthquake prediction, but weaknesses in traditional approaches to seismic hazards have become more and more evident. Remote sensing was used with earth observation technology, which is a new method that can instantly acquire a large area of abnormal information caused by earthquakes. In this paper, a popular method was tested in Sichuan but it did not perform well in earthquake predictions of this area. The causes have also been studied.
Jianfei Wang, Jingfa Zhang, Lixia Gong, Qiang Li, and Dan Zhou
Nat. Hazards Earth Syst. Sci., 18, 3253–3266,Short summary
This paper focused on the indirect economic losses caused by the Wenchuan earthquake in 2008 and evaluated the progress of restoration and reconstruction based on nighttime light images. Results show that the GDP has a quadratic function relationship with the total nighttime lights under normal conditions, and the economy of the disaster area after the earthquake showed unstable and turbulent development. This research provides a basis for macro-control of earthquake recovery and reconstruction.
Avith Mendoza-Ponce, Angel Figueroa-Soto, Diana Soria-Caballero, and Víctor Hugo Garduño-Monroy
Nat. Hazards Earth Syst. Sci., 18, 3121–3135,Short summary
This research carries out an investigation of the dynamics of the Pátzcuaro–Acambay fault system in central Mexico. We use a fractal analysis of slip rates and magnitudes Mw, estimated from fault length to define faults that are susceptible of generating earthquakes. We found that 316 faults are active and moreover the existence of three zones with different deformation processes. The implications of this new micro-regionalization are very important in order to reduce seismic hazard.
Alicia Rivas-Medina, Belen Benito, and Jorge Miguel Gaspar-Escribano
Nat. Hazards Earth Syst. Sci., 18, 2809–2823,Short summary
We present an approach for seismic hazard assessment that considers a hybrid source model composed of faults and zones containing the remaining seismicity. The seismic-moment rate is used to distribute seismic potential, avoiding double counting. The approach is applied in SE Spain, a region of low-to-moderate seismicity. Results show a concentration of expected accelerations around fault traces using the hybrid approach, which is not appreciated in the classic approach using zones exclusively.
Daniel Weijie Loi, Mavinakere Eshwaraiah Raghunandan, and Varghese Swamy
Nat. Hazards Earth Syst. Sci., 18, 2387–2408,Short summary
This work presents deterministic and probabilistic seismic hazard assessments for Peninsular Malaysia by considering far-field (> 400 km) Sumatran and local intraplate earthquake sources (2004–2016 from 19 stations). Our results predict the central-western peninsula experiencing higher ground motions due to events from Sumatran sources. Our predicted acceleration values are well within the allowable design limits as per the Annex drafted in 2016 by the Department of Standards Malaysia.
Sergey Tyagunov, Sergiy Vorogushyn, Cristina Muñoz Jimenez, Stefano Parolai, and Kevin Fleming
Nat. Hazards Earth Syst. Sci., 18, 2345–2354,Short summary
A methodological framework for the multi-hazard (earthquake and flood) failure analysis of fluvial dikes due to liquefaction is presented. Failure probability of the earthen structures is presented in the form of a fragility surface as a function of both seismic and hydraulic load. It is emphasized that the potential interactions between the two hazards should not be ignored in risk analyses and decision-making.
Nat. Hazards Earth Syst. Sci., 18, 1969–1983,Short summary
Numerical simulations are made for exploring rictional and viscous effects on earthquake recurrence based on a one-body spring-slider model with thermal-pressurized slip-weakening friction and viscosity. Included also is the effect due to wear process of faults, which can change long-term behavior of earthquakes.
Wei Wang, Hong Chen, Aihui Xu, and Minhao Qu
Nat. Hazards Earth Syst. Sci., 18, 1771–1783,Short summary
This paper provides a detailed introduction to the disaster situation of the 8 August 2017, Ms 7.0 earthquake that occurred in Jiuzhaigou County, Sichuan Province, China, and specifically describes the emergency response activities of all levels of the government, various departments, rescue teams, enterprises and public institutions as well as social organizations. The characteristics of the earthquake disaster and the emergency responses are analysed and summarized.
Nat. Hazards Earth Syst. Sci., 18, 1665–1679,Short summary
This study constructs a comprehensive dataset of global strong ground motion data to define new concepts of earthquake location and strong shaking area. These concepts can help to facilitate a more effective communication of the natural hazard of earthquakes that is focused on surface shaking. Past earthquake shaking is analyzed to support a transition of the discussion of earthquakes from seismology to a geography context and thus foster improved social science research on earthquake impacts.
Xiao-Wei Tang, Xu Bai, Ji-Lei Hu, and Jiang-Nan Qiu
Nat. Hazards Earth Syst. Sci., 18, 1451–1468,
Zhong-Hu Jiao, Jing Zhao, and Xinjian Shan
Nat. Hazards Earth Syst. Sci., 18, 1013–1036,Short summary
This paper dedicatedly reviews the progress and development of pre-seismic precursors and anomaly detection methods in this decade. Although several important problems still remain in this domain at present, developments of these two aspects can enrich available information sources, provide advanced tools for multilevel earthquake monitoring, and improve short- and medium-term forecasting, which should play a large and growing role in pre-seismic anomaly research from optical satellite data.
Ramazan Livaoğlu, Mehmet Ömer Timurağaoğlu, Cavit Serhatoğlu, and Mahmud Sami Döven
Nat. Hazards Earth Syst. Sci., 18, 921–934,Short summary
The paper discusses the seismological aspects of the 6–24 February 2017 Ayvacık (Çanakkale) earthquake swarm, describes the classifications of buildings in the area and elaborates on the performance of various building types during the earthquakes, and evaluates the damage distributions according to villages, damage ratios, structures and damage levels.
Darren N. King, Wendy S. Shaw, Peter N. Meihana, and James R. Goff
Nat. Hazards Earth Syst. Sci., 18, 907–919,
Esther Hintersberger, Kurt Decker, Johanna Lomax, and Christopher Lüthgens
Nat. Hazards Earth Syst. Sci., 18, 531–553,Short summary
The Vienna Basin is a low seismicity area, where historical data do not identify all potential earthquake sources. Despite observed Quaternary offset, there are no earthquakes along the Markgrafneusiedl Fault (MF). Results from 3 palaeoseismic trenches show evidence for 5–6 earthquakes with magnitudes up to M = 6.8 during the last 120 kyr. Therefore the MF should be considered as a seismic source, together with similar faults in the Vienna Basin, increasing the seismic potential close to Vienna.
Matan Avital, Ronnie Kamai, Michael Davis, and Ory Dor
Nat. Hazards Earth Syst. Sci., 18, 499–514,Short summary
We perform a hazard sensitivity study for two sites in Israel, exploring effects of uncertainty on the calculated seismic hazard. We account for uncertainty in the earthquake source properties, such as their geometric representation and seismic activity. We also account for uncertainty in the wave propagation path, by using alternative models to describe the ground motion calculations. We conclude that the current practice in Israel should be updated as it is probably underestimating the hazard.
Paolo Boncio, Francesca Liberi, Martina Caldarella, and Fiia-Charlotta Nurminen
Nat. Hazards Earth Syst. Sci., 18, 241–256,Short summary
The criteria for zoning the surface fault rupture hazard (SFRH) along-thrust faults are defined by analysing the characteristics of the areas of coseismic surface faulting in thrust earthquakes. The results and the database made available as supplementary material can be used for improving the attenuation relationships for distributed faulting, with possible applications in probabilistic studies of fault displacement hazard.
Mehmet F. Yılmaz and Barlas Ö. Çağlayan
Nat. Hazards Earth Syst. Sci., 18, 231–240,Short summary
This study focuses on the determination of seismic behavior and safety of specific bridges under seismic conditions. One of the nine intensity measures is selected considering practicality, efficiency, and proficiency. Component and system fragility curves are derived considering serviceability limits and component capacity. The results show that serves velocity limits has important effects on fragility curves of bridges and truss piers elements are the most vulnerable elements in the system.
Luis Moya, Fumio Yamazaki, Wen Liu, and Masumi Yamada
Nat. Hazards Earth Syst. Sci., 18, 65–78,Short summary
On 14 April 2016, an Mw 6.5 earthquake occurred in Kumamoto prefecture, Japan (foreshock). About 28 h later, another earthquake of Mw 7.0 occurred (mainshock). The earthquake produced extensive losses to the infrastructure. This paper shows the extraction of collapsed buildings from a pair of airborne lidar data recorded before and after the mainshock. A number of methods were applied and their performances were evaluated by comparison with actual data obtained from a field survey.
Zeynep Gülerce, Kadir Buğra Soyman, Barış Güner, and Nuretdin Kaymakci
Nat. Hazards Earth Syst. Sci., 17, 2365–2381,Short summary
This contribution provides an updated planar seismic source characterization (SSC) model to be used in the probabilistic seismic hazard assessment (PSHA) for Istanbul. The state-of-the-art SSC model presented here is the first fully documented and ready-to-use fault-based SSC model developed for the PSHA of Istanbul.
Alessandro Valentini, Francesco Visini, and Bruno Pace
Nat. Hazards Earth Syst. Sci., 17, 2017–2039,Short summary
In this paper, we present the results of an alternative seismogenic source model for use in a probabilistic seismic hazard assessment for Italy that integrates active fault and seismological data. Combining active faults and background sources is one of the key aspects in this type of approach. The strength of our approach lies in its ability to integrate different levels of available information for active faults in Italy or elsewhere.
Laura Peruzza, Raffaele Azzaro, Robin Gee, Salvatore D'Amico, Horst Langer, Giuseppe Lombardo, Bruno Pace, Marco Pagani, Francesco Panzera, Mario Ordaz, Miguel Leonardo Suarez, and Giuseppina Tusa
Nat. Hazards Earth Syst. Sci., 17, 1999–2015,Short summary
It is well known that volcanoes and earthquakes are associated, and some active volcanoes cause damaging earthquakes. Nonetheless, volcanoes usually are not pinpointed on a hazard map, as the effects of shallow, volcanic earthquakes can be overshadowed by stronger tectonic earthquakes in the region, particularly when long exposure periods are considered. In this study we faced some challenges with software implementations and original concept scheme for an original PSHA at Mt. Etna, Italy.
Raffaele Azzaro, Graziella Barberi, Salvatore D'Amico, Bruno Pace, Laura Peruzza, and Tiziana Tuvè
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In the present study, mapping of probability of exceedance of peak ground acceleration and spectral acceleration for the Patna district is presented considering both classical and zoneless approaches through the logic tree framework to capture the epistemic uncertainty.
In the present study, mapping of probability of exceedance of peak ground acceleration and...