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Neo-deterministic seismic hazard assessment (NDSHA) is based on the geophysical and seismotectonic features of a region and adopts a multiscale approach (i.e., regional and local) and multiscenario approach. This methodology has been successfully applied to many regions worldwide and, for the purpose of seismic microzoning, to several urban areas, including lifelines, relevant buildings, and cultural heritage sites. NDSHA naturally supplies realistic time series of ground motion, including reliable estimates of ground displacement readily applicable to seismic isolation techniques, useful to preserve historical monuments and relevant man-made structures. In this way, it creates a viable bridge between the seismological and the engineering community. We discuss here its application to the cities of Rome (where the first seismic microzonation study was developed using NDSHA), Valparaiso (where one of the first multihazard study was developed), and Trieste (where the first NDSHA study for seismic verification was conducted). This contribution should be intended as a sort of an illustrative, but definitely not exhaustive, view in space and time through possible NDSHA applications at a local scale.

Understanding of lithosphere dynamics, tectonic stress localization, earthquake occurrences, and seismic hazards has significantly advanced during the last decades. Meanwhile, despite the major advancements in geophysical sciences, yet we do not see a decline in earthquake disaster impacts and losses. Although earthquake disasters are mainly associated with significant vulnerability of society, comprehensive seismic hazards assessments and earthquake forecasting could contribute to preventive measures aimed to reduce impacts of earthquakes. Modeling of lithosphere dynamics and earthquake simulations coupled with a seismic hazard analysis can provide a better assessment of potential ground shaking due to earthquakes. Here we present a block-and-fault dynamics (BAFD) model, which simulates earthquakes due to lithosphere dynamics and allows for studying the influence of fault network properties and regional movements on seismic patterns. The model's performance is analyzed in terms of reproduction of basic features of the observed seismicity such as the frequency-magnitude relationship, clustering of earthquakes, occurrences of large events, fault slip rates, and earthquake mechanisms. Several studies related to the application of the BAFD model to the following earthquake-prone regions are reviewed: the southeastern Carpathians, Caucasus, the western India, Tibet-Himalaya, and the Sunda Arc. We examine then a new approach to seismic hazard analysis, which is based on instrumentally recorded, historical and BAFD-simulated earthquakes, and analyze how earthquake modeling can assist in hazard assessment. Finally, we discuss perspectives in modeling of earthquake occurrences and improvements in hazard assessment.

We study the spatio-temporal characteristics of earthquakes, and find that power laws and allometric growth laws are both statistically significant in the seismic dataset. For further analyzing the complexity of earthquake sequence, an approach of weighted earthquake networks modeling is presented with using the seismic and rock mass datasets. The rock masses covering the entire region are used to divide the region into a lot of small areas. It is shown that the distributions of connectivities and link weights both follow power law decay forms. The discovery of allometric growth laws is important for studying the dynamics of massive earthquakes. The suggested earthquake network is helpful to study the interactions between rock masses and expand a research prototype for modeling seismicity on complex networks.

Current computational resources and physical knowledge of the seismic wave generation and propagation processes allow for reliable numerical and analytical models of waveform generation and propagation. From the simulation of ground motion, it is easy to extract the desired earthquake hazard parameters. Accordingly, a scenario-based approach to seismic hazard assessment has been developed, namely the neo-deterministic seismic hazard assessment (NDSHA), which allows for a wide range of possible seismic sources to be used in the definition of reliable scenarios by means of realistic waveforms modelling. Such reli- able and comprehensive characterization of expected earthquake ground motion is essential to improve building codes, particularly for the protection of critical infrastructures and for land use planning. Parvez et al. (Geophys J Int 155:489–508, 2003) published the first ever neo-deterministic seismic hazard map of India by computing synthetic seismograms with input data set consisting of structural models, seismogenic zones, focal mechanisms and earthquake catalogues. As described in Panza et al. (Adv Geophys 53:93–165, 2012), the NDSHA methodology evolved with respect to the original formulation used by Parvez et al. (Geophys J Int 155:489–508, 2003): the computer codes were improved to better fit the need of producing real- istic ground shaking maps and ground shaking scenar- ios, at different scale levels, exploiting the most significant pertinent progresses in data acquisition and modelling. Accordingly, the present study supplies a revised NDSHA map for India. The seismic hazard, expressed in terms of maximum displacement (Dmax), maximum velocity (Vmax) and design ground acceleration (DGA), has been extracted from the synthetic signals and mapped on a regular grid over the studied territory.

In this paper, seismic risk scenarios for Bucharest, the capital city of Romania, are proposed and assessed. Bucharest has one of the highest seismic risk levels in Europe, and this is due to a combination of relatively high seismic hazard and a building stock built mainly before the devastating Vrancea 1977 earthquake. In this study, the seismic risk of Bucharest is assessed using the most recent information regarding the characteristics of the residential building stock. The ground motion amplitudes are evaluated starting from random fields obtained by coupling a ground motion model derived for the Vrancea intermediate-depth seismic source with a spatial correlation model. The seismic risk evaluation method applied in this study is based on the well-known macroseismic method. For several structural typologies, the vulnerability parameters are evaluated based on a damage survey performed on 18,000 buildings in Bucharest after the March 1977 earthquake. Subsequently, the risk metrics are compared with those from other studies in the literature that apply a different risk assessment methodology in order to gain a better view of the uncertainties associated with a seismic risk study at city level. Finally, the impact of several Vrancea intermediate-depth earthquake scenarios is evaluated and the results show that the earthquake which has the closest epicenter to Bucharest appears to be the most damaging.

This work focuses on the evaluation of the seismic hazard for Romania using earthquake catalogues generated by a Monte Carlo approach. The seismicity of Romania can be attributed to the Vrancea intermediate-depth seismic source and to 13 other crustal seismic sources. The recurrence times of large magnitude seismic events (both crustal and subcrustal), as well as the moment release rates are computed using simulated earthquake catalogues. The results show that the largest contribution to the overall moment release for the crustal seismic sources is from the seismic regions in Bulgaria, while the seismic regions in Romania contribute less than 5% of the overall moment release. In addition, the computations show that the moment release rate for the Vrancea subcrustal seismic source is about ten times larger than that of all the crustal seismic sources. Finally, the Monte Carlo approach is used to evaluate the seismic hazard for 20 cities in Romania with populations larger than 100,000 inhabitants. The results show some differences between the seismic hazard values obtained through Monte-Carlo simulation and those in the Romanian seismic design code P100-1/2013, notably for cities situated in the western part of Romania that are influenced by local crustal seismic sources.

From several decades ago, the average shear wave velocity for the top 30 m (Vs30) has been proposed as one of the important factors that reflects the amplification behavior of a site. Most of seismic design standards such as National Earthquake Hazards Reduction Program in the United States and Standard No. 2800 in Iran emphasize on the use of Vs30 measurements for site classification according to the soil type. As an important step in profound seismic risk reduction to earthquakes, a site effect study was conducted at a nationwide scale. We followed an indirect method to produce Vs30 map of Iran from geological and topographical data. The outputs indicate that hybrid Vs30 map has better performance than single topography-based Vs30 map. The amplitude map deduced from Vs30 and geology maps then is used for seismic microzonation of Tabriz city and extent of geographical distribution of damage for a possible deterministic scenario (M=7) is investigated through considering different fragility curves to describe damaging behavior of ordinary building types in the city.

The main goal of this work is to: (1) argue for the importance of a physically-based probabilistic seismic hazard analysis (pb-PSHA) methodology and show examples to support the argument from recent events, (2) demonstrate the methodology with the ground motion simulations of May 28, 1998, Mw = 5.5 Ras-Elhekma earthquake, north Egypt. The boundaries for the possible rupture parameters that may have been identified prior to the 1998 Ras-Elhekma earthquake were estimated. A range of simulated ground-motions for the Ras-Elhekma earthquake was “predicted” for frequency 0.5–25 Hz at three sites, where the large earthquake was recorded, with average epicentral distances of 220 km. The best rupture model of the 1998 Ras-Elhekma earthquake was identified by calculated the goodness of fit between observed and synthesized records at sites FYM, HAG, and KOT. We used the best rupture scenario of the 1998 earthquake to synthesize the ground motions at interested sites where the main shock was not recorded. Based on the good fit of simulated and observed seismograms, we concluded that this methodology can provide realistic ground motion of an earthquake and highly recommended for engineering purposes in advance or foregoing large earthquakes at non record sites. We propose that there is a need for this methodology for good-representing the true hazard with reducing uncertainties.

Thematic maps, such as seismic risk maps, are a useful tool that researchers use for representing the adverse outcomes that a natural catastrophic event can have over the territory. Generally, in those studies, major attention is focused in urban areas, where the human activities are concentrated. Main concerns are about the existing building stock, mostly composed by structures not compliant with modern seismic design criteria. The realization of a risk map is a complex task that involves the combination of data coming from different field of expertise, such as geology, geotechnical and structural engineering. The paper describes how the application of prospecting and surveying techniques (geological surveys, drilling, down-hole, MASW) allowed a decisive improvement in the geological knowledge of the area, contributing to define the subsoil model for the purposes of seismic microzonation. The interpretation of geophysical and geotechnical data and their correlation with geological units are explained and finally the microzonatic map is presented. The paper also reports the seismic geotechnical characterization executed with laboratory tests including the resonant column and cyclic torsional shear test on undisturbed samples. The results are summarized in terms of variation of stiffness and damping with shear strain. Finally, the use of wireless sensor technology for structural monitoring has significant benefits when the time available for access is often severely limited, by representing an effective way of managing risks once that an area of concern has been identified. The aim of the study is the acquisition of a local knowledge on issues related to seismic risk that may affect urban areas, through the acquisition, management and sharing of complex information. The available information, collected by sensor network, have been combined together in a Geographical Information System tool. The results provide a reliable representation of the seismic risk at urban scale to be used when planning the mitigation measures to be undertaken in order to improve the prevention and reduction of the disastrous effects of the earthquakes.

Schools are the gathering place of the young generation. They are expected to act as a refuge after an earthquake. Even though Nepal has no building supervision system, the quality of school buildings receives necessary attention. During a field study conducted in mid-June, we summarised the seismic damage to 12 schools with various types of structures, including local characteristic reinforced concrete frames, cement-bonded or mud-bonded masonry and timber frames. The pros and cons of local construction technologies are discussed. Some interesting earthquake phenomena, such as the effects of forward directivity, site configuration, earthquake sequence and safe distance from a slope, are discussed. The geo-security evaluation of a proposed school site in mountainous Baramchi is also conducted.

WOS: 000438615600008 Over the years, several local and regional seismic hazard studies have been conducted for the estimation of the seismic hazard in Turkey using different statistical processing tools for instrumental and historical earthquake data and modeling the geologic and tectonic characteristics of the region. Recently developed techniques, increased knowledge and improved databases brought the necessity to review the national active fault database and the compiled earthquake catalogue for the development of a national earthquake hazard map. A national earthquake strategy and action plan were conceived and accordingly with the collaboration of the several institutions and expert researchers, the Revision of Turkish Seismic Hazard Map Project (UDAP-C-13-06) was initiated, and finalized at the end of 2014. The scope of the project was confined to the revision of current national seismic hazard map, using the state of the art technologies and knowledge of the active fault, earthquake database, and ground motion prediction equations. The following two seismic source zonation models are developed for the probabilistic earthquake hazard analysis: (1) Area source model, (2) Fault and spatial smoothing seismic source model (FSBCK). In this study, we focus on the development and the characterization of the Fault Source model, the background spatially smoothed seismicity model and intrinsic uncertainty on the earthquake occurrence-rates-estimation. Finally, PSHA results obtained from the fault and spatial smoothed seismic source model are presented for 43, 72, 475 and 2475 years return periods (corresponding to 69, 50, 10, and 2% probability of exceedance in 50 years) for PGA and 5% damped spectral accelerations at 0.2 and 1.0 s. AFAD (Disaster and Emergency Management Authority of Turkey) [UDAP-C-13-16] First, we would like to express our gratitude to Sinan Akkar for his kind coordination of the project titled as "The update of the seismic hazard maps of Turkey'', and to Mustafa Erdik for his suggestions and comments, which helped us to considerably improve the project. We would like to thank various local researchers who gave us feedback and comments: Tolga Yilmaz, Ahmet Yakut, from Middle East Technical University; Murat Utkucu from Sakarya University. We also acknowledge Laurentiu Danciu from ETHZ, Roberto Basili from INGV, and Tuba Eroglu Azak who wrote and improved the codes and some scripts used in the calculation of some parameters. The study has been sponsored by AFAD (Disaster and Emergency Management Authority of Turkey) under Project Code UDAP-C-13-16. We would also like to thank Dr. Baumont for his review and suggestions for the improvement of the manuscript.

The present paper discusses the use of an integrated remote sensing and Geographical Information System (GIS) techniques for evaluation of seismic hazard areas in Syria. In the proposed approach, we have used the Advanced Spaceborne Thermal Emission and Reflection Radiometer (Aster) satellite data, digital elevation data (30 m resolution), earthquake data, and active tectonic maps. Many important factors for evaluation of seismic hazard were identified and corresponding thematic data layers (past earthquake epicenters, active faults, digital elevation model, and slope) were generated. A numerical rating scheme has been developed for spatial data analysis using GIS to identify ranking of parameters for the evaluation of seismic hazard. The resulting earthquake potential map delineates the area into different relative susceptibility classes: high, moderate, low and very low. The potential earthquake map was validated by correlating the obtained different classes with the local probability that produced using conventional analysis of observed earthquakes. Using earthquake data of Syria and the peak ground acceleration (PGA) data are included in the model to develop final seismic hazard map based on Gutenberg-Richter ( a and b values) parameters and the concepts of local probability and recurrence time. The application of the proposed technique in Syrian region indicates that this method provides good estimate of seismic hazard map compared to those developed from traditional techniques deterministic (DSHA) and probabilistic seismic hazard (PSHA). For the first time, we have used numerous parameters in preparation of seismic hazard map. The evaluation of seismic hazard maps using the proposed model is found to be very realistic.

The parameters of the September 3, 1978, earthquake in the Western Caucasus are presented according to data from different seismological agencies. This event, along with the 1966 earthquake in Anapa, is the strongest seismic event in the region. The solutions suggested in the main international and national seismological agencies contradict the well-known fact that the earthquake did not have catastrophic consequences. This is confirmed only by the position of the epicenter according to GCMT data intended for determining somewhat different earthquake parameters: the focal mechanism and seismic moment. Despite the fact that there was no expedition to perform a macroseismic study of the earthquake, some information was collected by phone survey. Information on the spatial distribution of the macroseismic effect made it possible to more accurately determine the epicenter position according to the GCMT data.

In conventional seismic hazard analysis, uniform distribution over area and magnitude range is assumed for the evaluation of source seismicity which is not able to capture peculiar characteristic of near-fault ground motion well. For near-field hazard analysis, two important factors need to be considered: (1) rupture directivity effects and (2) occurrence of scenario characteristic ruptures in the nearby sources. This study proposed a simple framework to consider these two effects by modifying the predictions from the conventional ground motion model based on pulse occurrence probability and adjustment of the magnitude frequency distribution to account for the rupture characteristic of the fault. The results of proposed approach are compared with those of deterministic and probabilistic seismic hazard analyses. The results indicate that characteristic earthquake and directivity consideration both have significant effects on seismic hazard analysis estimates. The implemented approach leads to results close to deterministic seismic hazard analysis in the short period ranges (T 1.0 s). Finally, seismic hazard maps based on the proposed method could be developed and compared with other methods.

This paper focuses on the investigation of seismic risk for residential buildings situated in Bucharest, the capital city of Romania. With a population of nearly 2 million inhabitants and a residential building stock of more than 130,000 units, Bucharest represents a city with one of the highest seismic risks in Europe. The seismic risk is evaluated taking into consideration only the Vrancea intermediate-depth seismic source which exhibits a dominant influence on the seismic hazard in southern and eastern Romania (including Bucharest, as well). The analyses are conducted based on a Monte Carlo earthquake catalogue which covers a time span of 50,000 years and includes more than 13,000 seismic events with magnitudes M W ≥ 6.0. In addition, in order to account for the ground-motion variability throughout Bucharest, a recently developed spatial correlation model is applied. Thus, the influence of the ground-motion correlation on the damage estimates for Bucharest is evaluated, as well. The seismic risk estimates obtained for various earthquake scenarios show a significant variability of the results obtained and offer valuable information for the decision-makers from public institutions dealing with the risk management.

The aftershocks of the 2008 Wenchuan and 2013 Lushan earthquakes delineated a prominent 60-km-long “seismic gap.” The uncertainty regarding the near-future seismic potential of this seismic gap has become of increasing importance to both the scientific community and the public. Using paleoseismology, this study investigated the occurrence of the last major event in the seismic gap and then considered the future seismic potential. Based on image interpretation, trench excavation, radiocarbon and optically stimulated luminescence dating, and comparisons with historical earthquake rupture lengths, the most recent paleoearthquake (estimated magnitude: M6.5–7.0) along the Shuangshi–Dachuan Fault (SDF), which is the southern segment of the Longmen Shan Fault, was constrained to 640–1330 CE (very possibly, 876 CE). According to the most recent geological and geophysical findings, we suggest that the seismic gap (i.e., the SDF) could be capable of generating M6.0–7.0 earthquakes, but that the likelihood of such an occurrence in the near future is not very high.

During the 2011 Great East Japan earthquake occurring at the north-east pacific region, serious secondary disasters caused by collision of drifting containers or ships occurred in various structures when tsunami came. Disaster deterioration caused by earthquake and drifting object impact during earthquake and tsunami has become another problem. This study presents an effective method to evaluate the accumulative response of steel bridge under earthquake and large drifting object impact due to tsunami flow, and the earthquake and tsunami come from the same fault motion. The main innovation has to do with the quantification of the earthquake effect and the ship-impact effect due to earthquake-induced tsunami directly into ductility demands, a phenomenon which has not been studied in the past. A series of seismic response analysis and impact analysis are carried out, and damage to the main tower of bridge is evaluated by means of elastic-plastic finite element analysis. This study shows that piers of main tower of bridge can be severely damaged due to the earthquake and ship impact effect compared to only impact effect. An effective evaluated method that could be useful for evaluating damage of lifeline engineering under such mega earthquake and tsunami is proposed.

The Earthquake Model of Middle East (EMME) project was carried out between 2010 and 2014 to provide a harmonized seismic hazard assessment without country border limitations. The result covers eleven countries: Afghanistan, Armenia, Azerbaijan, Cyprus, Georgia, Iran, Jordan, Lebanon, Pakistan, Syria and Turkey, which span one of the seismically most active regions on Earth in response to complex interactions between four major tectonic plates i.e. Africa, Arabia, India and Eurasia. Destructive earthquakes with great loss of life and property are frequent within this region, as exemplified by the recent events of Izmit (Turkey, 1999), Bam (Iran, 2003), Kashmir (Pakistan, 2005), Van (Turkey, 2011), and Hindu Kush (Afghanistan, 2015). We summarize multidisciplinary data (seismicity, geology, and tectonics) compiled and used to characterize the spatial and temporal distribution of earthquakes over the investigated region. We describe the development process of the model including the delineation of seismogenic sources and the description of methods and parameters of earthquake recurrence models, all representing the current state of knowledge and practice in seismic hazard assessment. The resulting seismogenic source model includes seismic sources defined by geological evidence and active tectonic findings correlated with measured seismicity patterns. A total of 234 area sources fully cross-border-harmonized are combined with 778 seismically active faults along with background-smoothed seismicity. Recorded seismicity (both historical and instrumental) provides the input to estimate rates of earthquakes for area sources and background seismicity while geologic slip-rates are used to characterize fault-specific earthquake recurrences. Ultimately, alternative models of intrinsic uncertainties of data, procedures and models are considered when used for calculation of the seismic hazard. At variance to previous models of the EMME region, we provide a homogeneous seismic source model representing a consistent basis for the next generation of seismic hazard models within the region.

The historical earthquake of the 1894 in Atalanti, Greece, produced widespread liquefaction effects on the broader coastal area. Although this earthquake has been extensively studied in the past, its magnitude still remains controversial. In the present study, we propose an indirect method for assessing its magnitude by simulating the ground motion and liquefaction effects, caused by a scenario earthquake with the characteristics of the 1894 event, at several sites located at the coastal zone of Atalanti Bay. For this purpose, we utilize information about the near‐surface soil conditions obtained by geophysical tools, data of recent seismic events, and results of stochastic simulation of strong ground motion for the scenario earthquake of the 1894 event. We confirm the high liquefaction potential of the investigated sites and establish that the low limit of magnitude ( M w ) for the 1894 earthquake is equal to 7.0. Electronic Supplement: Results of liquefaction analysis.

The earthquake hazard is most important title in seismic design of buildings. One of ways to know this hazard is to know where the earthquake boundary is. Moreover, understanding of the future earthquakes location, can help to modify the seismic hazard maps. The b-values, is the effective parameter on future earthquake positioning. This study was conducted to variations of b-values in the Gutenberg-Richter relation were examined for tectonic earthquakes in the NW of Iran. Earthquake dates for this area are given from the ISC, NEIC and Engdahl catalogues for a period of 735 to 2017 were used for analysis. We separated earthquake catalogue in part 1(before 2000) and Part 2 (all events). Delineated zone from b-value distribution map in catalogue Part 1, showed us five seismic gap region (area A to E) with a potential for the occurrence of earthquakes in the near future. The results of Part 2 showed that in areas A, B and C the future earthquake had happened. Therefore, we are waiting for last seismic events in the D and E areas. This "seismic gaps" is a potential threat to the surrounding regions, such as the Nakhichevan and Rasht city.

A significant number of Chinese and international earthquake disaster surveys indicate active faults as the root cause of earthquakes. Areas along fault lines experience the most severe damage and a greater number of personal injuries compared to regions on either side of the fault. Therefore, by adopting the shallow seismic reflection method to accurately detect the location and distribution of active faults, and developing effective measures to evade active faults, we can reduce earthquake disaster damage and economic losses. On April 20, 2013, the Lushan Ms7.0 earthquake occurred near the Shuangshi-Dachuan Fault (SDF) in the southern section of the Longmenshan fault zone. Because of its relatively high rate of earthquake activity, complex seismo-tectonic environment, and unique geological conditions, achieving usable data with seismic reflection is not easy. For that reason, available shallow seismic data of the SDF is extremely scarce. In our work, we carefully designed a survey to meet the constraints of the project and we have identified the precise location and near-surface structural form of the NE-trending SDF in the disaster area of the earthquake. The seismic surveys were located in Shuangshi Town of Lushan County and Daxi of Baoxing County. The detection of the SDF provided a scientific basis for selecting sites for post-disaster recovery and reconstruction to avoid these active fault zones, and reduce possible disastrous losses that could be caused by future earthquakes.

The approach in China since the last 1.5 decade for using apparent stress in time-dependent seismic hazard assessment or earthquake forecast is summarized. Retrospective case studies observe that apparent stress exhibits short-term increase, with time scale of several months, before moderate to strong earthquakes in a large area surrounding the ‘target earthquake’. Apparent stress is also used to estimate the tendency of aftershock activity. The concept relating apparent stress indirectly to stress level is used to understand the properties of some ‘precursory’ anomalies. Meanwhile, different opinions were reported. Problems in the calculation also existed for some cases. Moreover, retrospective studies have the limitation in their significance as compared to forward forecast test. Nevertheless, this approach, seemingly uniquely carried out in a large scale in mainland China, provides the earthquake catalogs for the predictive analysis of seismicity with an additional degree of freedom, deserving a systematic review and reflection.

The 7.8 Mw Gorkha earthquake struck the east of Lamjung in Nepal, followed by a sequence of powerful aftershocks. Chinese Team Six including the authors inspected the seismic damage to civil structures along 10 paths in densely populated areas with a seismic intensity of VII to IX, 40 days after the main shock. The damage was categorized according to structure types and described in detail. Several conclusions are made: powerful aftershocks can significantly affect the failure patterns; geological conditions, structure types, and height have great influence on the level of damage; and the local risky retrofitting technique needs improvement badly.

Earthquake event keeps increasing every year, and the recent cases of earthquake hazards invoke the necessity of seismic study in Korea, as geotechnical earthquake hazards, such as strong ground motion, liquefaction and landslides, are a significant threat to structures in industrial hub areas including coastal facilities. In this study, systemized framework of integrated assessment of earthquake-induced geotechnical hazard was established using advanced geospatial database. And a visible simulation of the framework was specifically conducted at two coastal facility areas in Incheon. First, the geospatial-grid information in the 3D domain were constructed with geostatistical interpolation method composed of multiple geospatial coverage mapping and 3D integration of geo-layer construction considering spatial outliers and geotechnical uncertainty. Second, the behavior of site-specific seismic responses were assessed by incorporating the depth to bedrock, mean shear wave velocity of the upper 30 m, and characteristic site period based on the geospatial-grid. Third, the normalized correlations between rock-outcrop accelerations and the maximum accelerations of each grid were determined considering the site-specific seismic response characteristics. Fourth, the potential damage due to liquefaction was estimated by combining the geospatial-grid and accelerations correlation grid based on the simplified liquefaction potential index evaluation method.

Seismic catalogues summarize information mainly on recent earthquakes and seismic events, recorded by means of relatively new instruments. Hence, this information, although being of high quality and quantitative value, sometimes is rather incomplete, since historical earthquakes are neglected in many cases. An example is the 1908 Cerbon earthquake (in Spain). This shake caused a good number of effects in the epicentre and surrounding area, triggering a huge landslide among some other effects. A complete geological and seismic site analysis, accompanied by a historical review of testimonies and journals of the time describing this particular earthquake, has been carried out, along with a deep field investigation to identify the mechanism of this landslide and the characteristics of the involved materials. A retrospective pseudo-static numerical simulation has been carried out to calculate the most probable range of peak horizontal accelerations during the earthquake. The results demonstrate the moderate relevance of this shake, also allowing us to quantify its objective importance. The presented methodology can be easily extended to some other similar cases, if seismic catalogues are to be completed for future designs accounting for seismic considerations.

Geophysical characterization of the subsurface by shallow seismic and electrical resistivity in conjunction with the geological conditions can provide more realistic information on earthquake hazard vulnerability assessment. Earthquake hazard vulnerability assessment requires not only the knowledge of earthquake source and propagation of seismic waves, but also local geological conditions which regulate ground shaking. Geophysical methods such as shallow seismic, electrical tomography, borehole geophysics and microtremor response are the most effective tools those contribute substantially in the earthquake hazard microzoning program. Strong-motion ground shaking character of a site due to an earthquake depends firstly on the magnitude of the source (moment magnitude, Mw) and the focal depth. However, fault reactivation can develop strong ground shaking at a site. Similarly, ground liquefaction can occur due to wave attenuation and amplification and can develop long residence time for ground shaking. Hence, earthquake hazard vulnerability of a site can be addressed more realistically taking into consideration of the source response, path response and site response. Groundwater condition and lithological variation of the subsurface zone can play an important role on the seismic response of a site. Geophysical parameters such as electrical resistivity, shear-wave velocity, dominant period and amplification factor in conjunction with geological information provide earthquake hazard vulnerability status. Earthquake hazard zoning is the first and the most important required step toward seismic risk analysis and mitigation strategy in the densely populated urban areas. Major earthquakes such as Bengal Earthquake in 1885 (also known as Manikganj Earthquake), 1897 Great Indian Earthquake and 1918 Srimangal Earthquake affected Dhaka Mega City of Bangladesh significantly. These earthquakes have been considered as the scenario earthquakes for hazard vulnerability assessment of Dhaka Mega City.

Seismic shaking and tectonic deformation during strong earthquakes can trigger widespread environmental effects. The severity and extent of a given effect relates to the characteristics of the causative earthquake and the intrinsic properties of the affected media. Documentation of earthquake environmental effects in well-instrumented, historical earthquakes can enable seismologic triggering thresholds to be estimated across a spectrum of geologic, topographic and hydrologic site conditions, and implemented into seismic hazard assessments, geotechnical engineering designs, palaeoseismic interpretations, and forecasts of the impacts of future earthquakes. The 2010–2011 Canterbury Earthquake Sequence (CES), including the moment magnitude (M w ) 7.1 Darfield earthquake and M w 6.2, 6.0, 5.9, and 5.8 aftershocks, occurred on a suite of previously unidentified, primarily blind, active faults in the eastern South Island of New Zealand. The CES is one of Earth's best recorded historical earthquake sequences. The location of the CES proximal to and beneath a major urban centre enabled rapid and detailed collection of vast amounts of field, geospatial, geotechnical, hydrologic, biologic, and seismologic data, and allowed incremental and cumulative environmental responses to seismic forcing to be documented throughout a protracted earthquake sequence. The CES caused multiple instances of tectonic surface deformation (≥ 3 events), surface manifestations of liquefaction (≥ 11 events), lateral spreading (≥ 6 events), rockfall (≥ 6 events), cliff collapse (≥ 3 events), subsidence (≥ 4 events), and hydrological (10s of events) and biological shifts (≥ 3 events). The terrestrial area affected by strong shaking (e.g. peak ground acceleration (PGA) ≥ 0.1–0.3 g), and the maximum distances between earthquake rupture and environmental response (R rup ), both generally increased with increased earthquake M w , but were also influenced by earthquake location and source characteristics. However, the severity of a given environmental response at any given site related predominantly to ground shaking characteristics (PGA, peak ground velocities) and site conditions (water table depth, soil type, geomorphic and topographic setting) rather than earthquake M w . In most cases, the most severe liquefaction, rockfall, cliff collapse, subsidence, flooding, tree damage, and biologic habitat changes were triggered by proximal, moderate magnitude (M w ≤ 6.2) earthquakes on blind faults. CES environmental effects will be incompletely preserved in the geologic record and variably diagnostic of spatial and temporal earthquake clustering. Liquefaction feeder dikes in areas of severe and recurrent liquefaction will provide the best preserved and potentially most diagnostic CES features. Rockfall talus deposits and boulders will be well preserved and potentially diagnostic of the strong intensity of CES shaking, but challenging to decipher in terms of single versus multiple events. Most other phenomena will be transient (e.g., distal groundwater responses), not uniquely diagnostic of earthquakes (e.g., flooding), or more ambiguous (e.g. biologic changes). Preliminary palaeoseismic investigations in the CES region indicate recurrence of liquefaction in susceptible sediments of ~ 100 to 300 yr, recurrence of severe rockfall event(s) of ca. 6000 to 8000 yr, and recurrence of surface rupturing on the largest CES source fault of ca. 20,000 to 30,000 yr. These data highlight the importance of utilising multiple proxy datasets in palaeoearthquake studies. The severity of environmental effects triggered during the strongest CES earthquakes was as great as or equivalent to any historic or prehistoric effects recorded in the geologic record. We suggest that the shaking caused by rupture of local blind faults in the CES comprised a ‘worst case’ seismic shaking scenario for parts of the Christchurch urban area. Moderate M w blind fault earthquakes may contribute the highest proportion of seismic hazard, be the most important drivers of landscape evolution, and dominate the palaeoseismic record in some locations on Earth, including locations distal from any identified active faults. A high scientific priority should be placed on improving the spatial extent and quality of ‘off-fault’ shaking records of strong earthquakes, particularly near major urban centres.

Earthquake could cause severe damage to the architectural heritage which should be conserved. The ground shaking by earthquake generates the dynamic loading to the structure on the surface and this dynamic loading can cause damage (such as collapse) to the structure. The magnitude of this dynamic loading is proportional to that of ground shaking. Therefore, seismic hazard can be determined through the evaluation of ground shaking. In this study, seismic hazard of architectural heritages in Seoul is evaluated by site investigation using surface wave method and site-specific ground response analysis.

Shear-wave velocity of the top 30 m, VS30, is commonly used for prediction of the seismic site response. This paper presents development, validation and uncertainty assessment of a regional VS30 model based on a combination of simplified 3D geology and statistically representative velocity values. Results identify soft marine sediments in deep sedimentary basins as zones most susceptible to seismic shaking. Compared to the available urban-scale seismic zonation studies, the regional model showed a success rate of roughly 64% in predicting local site category. The standard deviation was in average 30% of the expected VS30 value.

This paper is about short review of earthquake statistics and efforts for earthquake mitigation, hazard and risk assessment studies in Pakistan. Pakistan and adjoining region lying between longitude 60°E to 78°E and latitude 20°N to 45°N are selected for the study as this region has a history of many large earthquakes because of its location in the region of intersection of three plates namely Indian, Eurasian and Arabian Sea plate. This paper is based on the study of both seismological history of the region which includes recent and historical seismicity based on earthquake catalogue as well as geological knowledge supplemented with available fault system information. In this study, Pakistan and adjoining regions are divided into 14 seismogenic zones. Seismicity of each zone is studied considering also the major cities in the respective zone and type of infrastructure which is mainly responsible for earthquake disaster rather than earthquake itself.

Permanent deformation plays a key role in performance based earthquake resistant design. In order to estimate permanent deformation after earthquake, it is essential to secure reliable response history analysis(RHA) as well as earthquake scenario. This study focuses on permanent deformation of an inverted T-type wall under earthquake. The study is composed of two separate parts. The first one is on the verification of RHA and the second one is on an effect of input earthquake motion. The former is discussed in companion paper and the latter in this paper. In order to investigate the effect of an input earthquake motion on the permanent deformation, three bins of spectral matched real earthquake records with different magnitude, regions, epicentral distance are constructed. Parametric study was performed using the verified RHA through the companion paper for each earthquake records in the bins. The most influential parameter affecting permanent displacement is magnitude. The other parameters describing earthquake motion are not significant enough to increase permanent displacement of the inverted T-type wall except for energy related parameters(AI, CI, SEI).

In the last 900 years, the east coast of Sicily has been struck by several disastrous earthquakes. The earthquakes occurred in 1169, 1542, 1693, 1818, 1908 and more recently in 1990, with estimated magnitudes, ranging from less than 5.0 to greater than 7.0, testify the high level of hazard in this area. Many towns were destroyed during the above-mentioned earthquakes. The high level of seismicity that affects the area, together with the considerable high density of inhabitants living in its urban area, contribute to classify it as one of the area having the highest seismic risk in Italy. It is also not negligible the high potential damage to which its historic-architectural patrimony could undergo even at moderate magnitudes. Many researches show that the site seismic response is strongly influenced by stratigraphic and topographic features. Site response can reduce or amplify the earthquake induced ground motion. In this study seismic response of strategic building located in Catania has been done, and main results are presented.

Seismic microzonation is a process of estimating site-specific effects due to an earthquake on urban centers for its disaster mitigation and management. The state of West Bengal, located in the western foreland of the Assam–Arakan Orogenic Belt, the Himalayan foothills and Surma Valley, has been struck by several devastating earthquakes in the past, indicating the need for a seismotectonic review of the province, especially in light of probable seismic threat to its capital city of Kolkata, which is a major industrial and commercial hub in the eastern and northeastern region of India. A synoptic probabilistic seismic hazard model of Kolkata is initially generated at engineering bedrock (Vs30 ~ 760 m s−1) considering 33 polygonal seismogenic sources at two hypocentral depth ranges, 0–25 and 25–70 km; 158 tectonic sources; appropriate seismicity modeling; 14 ground motion prediction equations for three seismotectonic provinces, viz. the east-central Himalaya, the Bengal Basin and Northeast India selected through suitability testing; and appropriate weighting in a logic tree framework. Site classification of Kolkata performed following in-depth geophysical and geotechnical investigations places the city in D1, D2, D3 and E classes. Probabilistic seismic hazard assessment at a surface-consistent level – i.e., the local seismic hazard related to site amplification performed by propagating the bedrock ground motion with 10% probability of exceedance in 50 years through a 1-D sediment column using an equivalent linear analysis – predicts a peak ground acceleration (PGA) range from 0.176 to 0.253 g in the city. A deterministic liquefaction scenario in terms of spatial distribution of liquefaction potential index corresponding to surface PGA distribution places 50% of the city in the possible liquefiable zone. A multicriteria seismic hazard microzonation framework is proposed for judicious integration of multiple themes, namely PGA at the surface, liquefaction potential index, NEHRP soil site class, sediment class, geomorphology and ground water table in a fuzzy protocol in the geographical information system by adopting an analytical hierarchal process. The resulting high-resolution surface consistent hazard, liquefaction and microzonation maps are expected to play vital roles in earthquake-related disaster mitigation and management of the city of Kolkata.

Seismic hazard assessment is done for oil field areas in the North Caspian region by a method earlier successfully applied to other areas. The method involves general seismic zoning data, available regional databases on recurrence of seismic shaking, known models of ground motion attenuation in seismoactive regions, and data on geological and geophysical surveys in the studied area. The assigned level of seismic hazard of the region is refined using probabilistic analysis; additionally, disaggregation is made and accelerograms are synthesized (the latter are necessary for seismic microzoning of particular sites using the numerical nonlinear analysis of ground seismic response). The amplitude and spectral characteristics of ground motions are obtained which are necessary for seismic resistance design and construction of petroleum industry objects.

The main objective of this paper was to introduce the Environmental Seismic Intensity scale (ESI), a new scale developed and tested by an interdisciplinary group of scientists (geologists, geophysicists and seismologists) in the frame of the International Union for Quaternary Research (INQUA) activities, to the widest community of earth scientists and engineers dealing with seismic hazard assessment. This scale defines earthquake intensity by taking into consideration the occurrence, size and areal distribution of earthquake environmental effects (EEE), including surface faulting, tectonic uplift and subsidence, landslides, rock falls, liquefaction, ground collapse and tsunami waves. Indeed, EEEs can significantly improve the evaluation of seismic intensity, which still remains a critical parameter for a realistic seismic hazard assessment, allowing to compare historical and modern earthquakes. Moreover, as shown by recent moderate to large earthquakes, geological effects often cause severe damage''; therefore, their consideration in the earthquake risk scenario is crucial for all stakeholders, especially urban planners, geotechnical and structural engineers, hazard analysts, civil protection agencies and insurance companies. The paper describes background and construction principles of the scale and presents some case studies in different continents and tectonic settings to illustrate its relevant benefits. ESI is normally used together with traditional intensity scales, which, unfortunately, tend to saturate in the highest degrees. In this case and in unpopulated areas, ESI offers a unique way for assessing a reliable earthquake intensity. Finally, yet importantly, the ESI scale also provides a very convenient guideline for the survey of EEEs in earthquake-stricken areas, ensuring they are catalogued in a complete and homogeneous manner

Many efforts have been made to quickly estimate the maximum runup height of tsunamis associated with large earthquakes. This is a difficult task because of the time it takes to construct an accurate tsunami model using real-time data from the source. It is possible to construct a database of potential seismic sources and their corresponding tsunami a priori. However, such models are generally based on uniform slip distributions and thus oversimplify the knowledge of the earthquake source. Here we show how to predict tsunami runup from any seismic source model using an analytic solution that is specifically designed for subduction zones with a well-defined geometry, i.e., Chile, Japan, Nicaragua, and Alaska. The main idea of this work is to provide a tool for emergency response, trading off accuracy for speed. The solutions we present for large earthquakes appear promising. Here runup models are computed for the following: the 1992 Mw 7.7 Nicaragua earthquake, the 2001 Mw 8.4 Peru earthquake, the 2003 Mw 8.3 Hokkaido earthquake, the 2007 Mw 8.1 Peru earthquake, the 2010 Mw 8.8 Maule earthquake, the 2011 Mw 9.0 Tohoku earthquake, and the recent 2014 Mw 8.2 Iquique earthquake. The maximum runup estimations are consistent with measurements made inland after each event, with a peak of 9 m for Nicaragua, 8 m for Peru (2001), 32 m for Maule, 41 m for Tohoku, and 4.1 m for Iquique. Considering recent advances made in the analysis of real-time GPS data and the ability to rapidly resolve the finiteness of a large earthquake close to existing GPS networks, it will be possible in the near future to perform these calculations within the first minutes after the occurrence of similar events. Thus, such calculations will provide faster runup information than is available from existing uniform-slip seismic source databases or past events of premodeled seismic sources.

The extensive damage to buildings caused by the Nepal Ms 8.1 earthquake has attracted much attention by the international community. After the preliminary scientific investigations on the different affected areas in Nepal, the construction and damage characteristics of five different types of buildings commonly existing in Nepal were discussed and the reasons of their disaster performance were analyzed. Types of buildings investigated include reinforced concrete (RC) frame structures, rubble structures, brick-wood structures, raw soil structures, and brick-wood structures of historic buildings. In addition, the weak links of the seismic design were pointed out, which was very important for the post-earthquake reconstruction and recovery, and gave a preliminary explanations for the damage experienced.

The paper presents new criteria of seismic and rock burst hazard assessment in Polish hard coal mines where longwall mining system is common practice. The presented criteria are based on the results of continuous recording of seismic events and analysis of selected seismological parameters: spatial location of seismic event in relation to mining workings, seismic energy, seismic energy release per unit coal face advance, b-value of Gutenberg-Richter law, seismic energy index EI, seismic moment M0, weighted value of peak particle velocity PPVW. These parameters are determined in a moving daily time windows or time windows with fixed number of seismic tremors. Time changes of these parameters are then compared with mean value estimated in the analyzed area. This is the basis to indicate the zones of high seismic and rock burst hazard in specific moment in time during mining process. Additionally, the zones of high seismic and rock burst hazard are determined by utilization of passive seismic tomography method. All the calculated seismic parameters in moving time windows are used to quantify seismic and rock burst hazard by four level scales. In practice, assessment of seismic and rock burst hazard is used to make daily decision about using rock burst prevention activities and correction of further exploitation of monitored coal panel.

We present a new approach to assessment of regional seismic hazard, which accounts for observed (instrumentally recorded and historic) earthquakes, as well as for seismic events simulated for a significantly longer period of time than that of observations. We apply this approach to probabilistic seismic hazard analysis (PSHA) for the Tibet–Himalayan region. The large magnitude synthetic events, which are consistent with the geophysical and geodetic data, together with the observed earthquakes are employed for the Monte-Carlo PSHA. Earthquake scenarios for hazard assessment are generated stochastically to sample the magnitude and spatial distribution of seismicity, as well as the distribution of ground motion for each seismic event. The peak ground acceleration values, which are estimated for the return period of 475 yr, show that the hazard level associated with large events in the Tibet–Himalayan region significantly increases if the long record of simulated seismicity is considered in the PSHA. The magnitude and the source location of the 2008 Wenchuan M = 7.9 earthquake are among the range of those described by the seismic source model accepted in our analysis. We analyze the relationship between the ground motion data obtained in the earthquake's epicentral area and the obtained PSHA estimations using a deaggregation technique. The proposed approach provides a better understanding of ground shaking due to possible large-magnitude events and could be useful for risk assessment, earthquake engineering purposes, and emergency planning.

Based on the reconnaissance of buildings in Dujiangyan City during 2008 Wenchuan earthquake, China, structural damage characteristics and the spatial distribution of structural damage are investigated, and the possible reasons for the extraordinary features are discussed with consideration of the influence of urban historical evolution and spatial variation of earthquake motions. Firstly, the urban plan and typical characteristics of structural seismic damage are briefly presented and summarized. Spatial distribution of structural damage is then comparatively analyzed by classifying all surveyed buildings in accordance with different construction age, considering the influence of seismic design code on urban buildings. Finally, the influences of evolution of seismic design code, topographic condition, local site and distance from fault rupture on spatial distribution of structural damage are comprehensively discussed. It is concluded that spatial variation of earthquake motions, resulting from topography, local site effect and fault rupture, are very important factor leading to the extraordinary spatial distribution of building damage except the evolution of seismic design codes. It is necessary that the spatial distribution of earthquake motions should be considered in seismic design of structures located in complicated topography area and near active faults.

Suez Canal is the most important navigational water stream in the world. It separates the eastern part of the Nile Delta from northern Sinai and controls 40 % of ship movement in the world. There is also the new Suez Canal project, which is one of the most important new projects in Egypt. The purpose of this study is to assess seismic hazards at and around Suez Canal. The technique used in hazard estimation is the probabilistic seismic hazard approach (PSHA). Alternative seismotectonic source models were included in the hazard assessment to account for the epistemic uncertainty. Contour maps were produced for ground motion on rock for spectral periods 0.2, 0.5, 1 and 2 s, as well as Peak Ground Acceleration (PGA) for return periods of 75, 475, 975 and 2475 years (equivalent to 20, 10, 5 and 2 % probability of exceeding ground motion in 50 years, respectively). The Uniform Hazard Spectra (UHS) was also estimated for some cities inside the study area on rock for return periods of 75, 475, 975 and 2475 years. The results show that the highest hazard level is at the southeastern part of the study area with maximum expected spectral acceleration of 280.3 cm/s2 (gal) at a spectral period of 0.2 s for a return period of 475 years. The results of this study can be used for seismic microzonation, seismic risk mitigation and for earthquake engineering purposes.

This paper describes an updated probabilistic seismic hazard analysis which estimates potential seismic ground motions on rock sites in Hong Kong based on a new seismic source model. A detailed catalogue of historical and recent earthquakes within the South China region was reviewed and updated using data up to 2009. A new seismic source model was developed based on the consideration of seismicity, geological and tectonic information of the region, especially the source zone boundaries that were used to produce seismic hazard maps in the current Chinese code for seismic design of buildings, GB50011 [1].

A seismic sequence that included a moment magnitude M W = 5.9 earthquake struck three regions of Northern Italy (Emilia Romagna, Veneto and Lombardy) in May–June 2012. The sequence caused significant damage to several historical buildings and in some cases caused complete structural collapse. Cracks appeared in the belfry and cusp of the 69 m high, ∼3° leaning bell tower of Ficarolo (Rovigo). A project aimed at studying the geometry of the tower, possible local seismic amplification and soil-structure interaction began in early 2013 before the earthquake. The data were provided by terrestrial laser scanning, low-cost operational modal analysis and geophysical measurements. The repetition of the surveys during and after the seismic sequence, which was augmented by thermal imaging measurements, allowed an evaluation of the changes caused by the earthquake. In addition to an evaluation of the damage, the data allowed the development of a method based on fast and relatively low-cost measurements that provide useful information for cultural heritage management purposes. The results highlighted that the surveys can be carried out during a seismic emergency and that preventive measures can be carried out under reasonable time and budget constraints in high seismic hazard areas.

damaged by Emilia-Romagna earthquake sequence of May 2012. The research suggests solutions for the rehabilitation of a masonry historic building that presents a serious damage pattern. The solutions includes the base isolation of the global structure. Through the historical analysis, the damage survey and the mechanisms analysis were defined the macro-structure of the palace. Subsequently, was generated different configurations based on the aggregation or separation of the five macro-structure identified. The separation of these proposed projects is done through the use of seismic isolators and dampers. It was carried out a simplified finite element model and the linear elastic dynamic modal analysis was performed to evaluate the main modes of vibration of each configuration, which correspond to the higher values of percentage of participating mass. Finally a response spectrum analysis was performed with the use of data of the earthquake of 29 May 2012. It going to evaluate the seismic behavior of all the configurations.

This study presents the design and implementation of a structural health monitoring system based on acceleration measurements which used to observe and investigate the structural performance of the administration building in Seoul National University of Education during an earthquake event. The frequency and spectrum are analyzed to assess the building performance during an earthquake shaking which took place on March 31st, 2014. The results indicate that : the vibration of the roof is more clear and dominant during the shaking, and the response of building during earthquake is so small and safe.