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Shebalin P. N. Gvishiani A. D. Dzeboev B. A. Skorkina A. A. 《Doklady Earth Sciences》2022,507(1):930-935
Doklady Earth Sciences - For the first time, a numerical comparison of the General Seismic Zoning (GSZ) maps with the effect of earthquakes that actually occurred after the publication of the maps... 相似文献
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The objective of this study is to evaluate the seismic hazard at the Esfarayen-Bojnurd railway using the probabilistic seismic hazard assessment (PSHA) method. This method was carried out based on a recent data set to take into account the historic seismicity and updated instrumental seismicity. A homogenous earthquake catalogue was compiled and a proposed seismic sources model was presented. Attenuation equations that recently recommended by experts and developed based upon earthquake data obtained from tectonic environments similar to those in and around the studied area were weighted and used for assessment of seismic hazard in the frame of logic tree approach. Considering a grid of 1.2 × 1.2 km covering the study area, ground acceleration for every node was calculated. Hazard maps at bedrock conditions were produced for peak ground acceleration, in addition to return periods of 74, 475 and 2475 years. 相似文献
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The cross-bordering earthquake hazard mapfor three Central European countries, the CzechRepublic, Poland and Slovakia (CZ-PL-SK) in thesense of the Global Seismic Hazard AssessmentProgram (GSHAP) was elaborated both in terms ofmacroseismic intensities and in terms of peak groundaccelerations (PGA). A new earthquake parametriccatalogue for CZ-PL-SK (Schenková et al., 1999)allows the source regions to be delineated withrespect to tectonic structures. Regions for Austriaand Germany were taken from the D-A-CH area withsome modifications in the border zone with the CzechRepublic and Poland. Regions of other surroundingcountries were defined with respect to nationalearthquake catalogues and geologico-geophysical dataof Central European countries. For each sourceregion earthquake data were normalised to obtain areliable annual recurrence graph and the maximumexpected earthquakes. Attenuation laws were definedto allow more advanced earthquake hazard maps to becalculated by the standard probabilistic McGuire's(1976) approach. The obtained GSHAP hazard maps forthe CZ-PL-SK area were calculated for the returnperiod of 475 years. Besides a comparison with thehazard values for the D-A-CH area (Grünthal etal., 1995, 1996; Grünthal, 1997), the map wasalso compared with the effective ground accelerationmap for Austria (Lenhardt, 1996) and in both cases avery good coincidence was found.Author for correspondence 相似文献
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YinKunlong ZhangGuirong ZhuLiangfeng 《中国地质大学学报(英文版)》2004,15(3):306-311
In recent years, China has suffered serious geological disasters, most of slope movements due to complex geology, geomorphology, unusual weather conditions, and large-scale land explorations during high speed economic development. According to geological hazard investigations organized by the Ministry of Land and Resources of China, there are 400 towns and more than 10000 villages under the threatening of those landslide hazards. This paper presents the overview landslide hazard assessment in terms of GIS, which aims to evaluate the overview geohazard potentials, vulnerabilities of lives and land resources, and risks in conterminous China on the scale of 1 : 6 000 000. This is the first overview landslide hazard potential map of China. 相似文献
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Quaternary tectonics and paleoseismologicalinvestigations have defined a reliable framework ofactive faults in the southern Umbria and AbruzziApennines. Two sets of NW–SE to NNW–SSE trending, 16to 33 km-long, normal and normal-oblique faults orfault systems have caused the displacement of LatePleistocene–Holocene deposits and landforms within theinvestigated sector. Available data on verticaloffsets indicate that both Late Pleistocene–Holoceneand Quaternary (since the later part of the EarlyPleistocene; 0.9–1 Ma) slip rates range between 0.4and 1.2 mm/yr (range 0.6–0.8 mm/yr preferred).Paleoseismological investigations show that recurrenceintervals for surface faulting events are alwaysgreater than 1,000 years and are usually greater than2,000 years. Both paleoseismological data andlong-term seismicity show that activation of theinvestigated faults may result in earthquakes ofM = 6.5–7.0. The extension rate across the two sets ofprimary faults ranges between 0.7 and 1.6 mm/yr.Horizontal seismic strain has been calculated to be0.5–0.6 mm/yr, based on the summation of the seismicmoment of M > 5.3 earthquakes which have affected theinvestigated area since 1200 AD. This value may belower than that inferred through geological data,probably because the seismological record reliable forthe addition of the seismic moments covers a too shorttime window (about 800 years) to be consideredrepresentative of the tectonic activity in theinvestigated area. This conclusion iscorroborated by the large recurrence intervalper fault (>1,000–2,000 years) inferred frompaleoseismological analysis. A comparison of theactive-fault framework and historical-seismicitydistribution indicates that the entire eastern set ofactive faults has likely not been activated since 1000AD, thus indicating that the elapsed time since thelast activation for several faults of the investigatedarea may be greater than 1,000 years. In terms ofhazard, the highest probability of activation isrelated to the eastern set faults, due to theobservation that the elapsed time for some of thesefaults may be similar to the recurrence interval. Asan example, paleoseismological andarchaeoseismological data indicate that the elapsedtime for the Mt. Vettore and Mt. Morrone Faults may begreater than 1,650 and 1,850 years, respectively.These data may have significant implications for riskrelated to a number of towns in central Italy and tothe city of Rome. As for the latter, in fact,monumental heritage has suffered significant damagedue to earthquakes of M > 6.5 which originated in theinvestigated Apennine sector. 相似文献
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The paper is dedicated to the review of methods of seismic hazard analysis currently in use, analyzing the strengths and weaknesses of different approaches. The review is performed from the perspective of a user of the results of seismic hazard analysis for different applications such as the design of critical and general (non-critical) civil infrastructures, technical and financial risk analysis. A set of criteria is developed for and applied to an objective assessment of the capabilities of different analysis methods. It is demonstrated that traditional probabilistic seismic hazard analysis (PSHA) methods have significant deficiencies, thus limiting their practical applications. These deficiencies have their roots in the use of inadequate probabilistic models and insufficient understanding of modern concepts of risk analysis, as have been revealed in some recent large scale studies. These deficiencies result in the lack of ability of a correct treatment of dependencies between physical parameters and finally, in an incorrect treatment of uncertainties. As a consequence, results of PSHA studies have been found to be unrealistic in comparison with empirical information from the real world. The attempt to compensate these problems by a systematic use of expert elicitation has, so far, not resulted in any improvement of the situation. It is also shown that scenario-earthquakes developed by disaggregation from the results of a traditional PSHA may not be conservative with respect to energy conservation and should not be used for the design of critical infrastructures without validation. Because the assessment of technical as well as of financial risks associated with potential damages of earthquakes need a risk analysis, current method is based on a probabilistic approach with its unsolved deficiencies.
Traditional deterministic or scenario-based seismic hazard analysis methods provide a reliable and in general robust design basis for applications such as the design of critical infrastructures, especially with systematic sensitivity analyses based on validated phenomenological models. Deterministic seismic hazard analysis incorporates uncertainties in the safety factors. These factors are derived from experience as well as from expert judgment. Deterministic methods associated with high safety factors may lead to too conservative results, especially if applied for generally short-lived civil structures. Scenarios used in deterministic seismic hazard analysis have a clear physical basis. They are related to seismic sources discovered by geological, geomorphologic, geodetic and seismological investigations or derived from historical references. Scenario-based methods can be expanded for risk analysis applications with an extended data analysis providing the frequency of seismic events. Such an extension provides a better informed risk model that is suitable for risk-informed decision making. 相似文献
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Ebru HARMANDAR 《《地质学报》英文版》2022,96(1):376-385
Fethiye is an important region located in the eastern part of the Mediterranean Basin.This region which is the most active part of the south-western Anatolia ex... 相似文献
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As a result of work carried out during the first two stages of the Global Seismic Hazard Assessment Program (GSHAP) for the Test Area Caucasus, a uniform earthquake catalogue was compiled and a Seismic Source Zones Model was designed. At the final stage of the program, the computation of seismic hazard was done by different methods.The results of a computation done using the Probabilistic Seismic Hazard Assessment methodology, as well as primary intermediate steps and preparatory work are given in the present paper. Peak horizontal ground acceleration is chosen as the parameter representing seismic hazard. Final computer calculations were done with the SEISRISK III program. The two final Seismic Hazard maps for different return periods are presented. The work was carried out at the National Survey for Seismic Protection of the Republic of Armenia. 相似文献
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The ‘twin cities' district of Rawalpindi–Islamabad is among the most endangered seismic regions in Pakistan,with the seismic hazard assessed(0.32 g) to intensity IX MMI for a 475-year return period. A seismic hazard map for Rawalpindi–Islamabad is presented herein, based on 85 shear-wave velocity(VS) profiles obtained through geophysical H/V measurements and from the geological map of the region. Relationships between the average top thirty-meter shear-wave velocities(VS30) and surficial geological units have been determined. The peak ground acceleration(PGA) maps for 150,475 and 2475-year return periods were converted into a seismic intensity map. Intensity increments for different soils were used to compute PGA values for 150, 475 and 2475-year return periods. Sites located on softer ground experienced a higher degree of damage from moderate earthquakes. Due to the presence of soft clay or lique?able soil and lateral spreading, a few locations may be classified as hybrid sites class C and D. This map is a critical step in facilitating code-based site classification and seismic design throughout Rawalpindi–Islamabad. Although the seismic hazard map based on seismic intensities is no longer used in engineering geology, it is still important in seismological analysis and for civil protection purposes. 相似文献
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The hazard assessment of potential earthquake-induced landslides is an important aspect of the study of earthquake-induced landslides. In this study, we assessed the hazard of potential earthquake-induced landslides in Huaxian County with a new hazard assessment method. This method is based on probabilistic seismic hazard analysis and the Newmark cumulative displacement assessment model. The model considers a comprehensive suite of information, including the seismic activities and engineering geological conditions in the study area, and simulates the uncertainty of the intensity parameters of the engineering geological rock groups using the Monte Carlo method. Unlike previous assessment studies on ground motions with a given exceedance probability level, the hazard of earthquake-induced landslides obtained by the method presented in this study allows for the possibility of earthquake-induced landslides in different parts of the study area in the future. The assessment of the hazard of earthquake-induced landslides in this study showed good agreement with the historical distribution of earthquake-induced landslides. This indicates that the assessment properly reflects the macroscopic rules for the development of earthquake-induced landslides in the study area, and can provide a reference framework for the management of the risk of earthquake-induced landslides and land planning. 相似文献
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The study computes time-dependant earthquake probabilities on the basis of seismicity data mainly deriving from historic records.
It provides a methodological approach useful for those countries where the scarcity of instrumental data and/or paleoseismological
evidences requires that historical information shall be stressed. Thus, the conditional probability that damaging earthquakes
(M ≥ 6) may occur in Italy in the next 30 years is shown, and the potential for the main worldwide known Italian cities with
a cultural heritage is outlined. Earthquake probabilities are computed referring to the application of renewal processes,
where the periodicity is analytically modelled by means of the Brownian Passage Time function; an estimate of the dispersion
(i.e., uncertainty) introduced on probabilities is provided making use of Monte Carlo simulations. The computed probabilities
refer to seismic source zones deriving from the spatial clustering of the historically documented seismicity. The computation
of probabilities based on the interaction of earthquakes occurring in nearby zones, has been also attempted for a test area
to explore the influence exerted by the stress transfer effect. The main findings of this study are that (1) seismic source
zones in Southern Italy are the most prone to experience damaging earthquakes in the next 30-years, with conditional probabilities
a large as 10%; and (2) the influence exerted by the earthquake interaction in increasing such probabilities, doesn’t seem
to be relevant, because the mean recurrence times of large earthquakes (above the threshold magnitude of six chosen in this
study) are in general much longer than the time shortening produced by the stress transfer. 相似文献
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Please?refer?to?the?attachment(s)?for?more?details. 相似文献
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Sheridan Michael F. Hubbard Bernard Carrasco-núñez Gerardo Siebe Claus 《Natural Hazards》2004,33(2):209-221
Volcán Citlaltépetl (Pico de Orizaba) with an elevation of 5,675 m is the highest volcano in North America. Its most recent catastrophic events involved the production of pyroclastic flows that erupted approximately 4,000, 8,500, and 13,000 years ago. The distribution of mapped deposits from these eruptions gives an approximate guide to the extent of products from potential future eruptions. Because the topography of this volcano is constantly changing computer simulations were made on the present topography using three computer algorithms: energy cone, FLOW2D, and FLOW3D. The Heim Coefficient (), used as a code parameter for frictional sliding in all our algorithms, is the ratio of the assumed drop in elevation (H) divided by the lateral extent of the mapped deposits (L). The viscosity parameter for the FLOW2D and FLOW3D codes was adjusted so that the paths of the flows mimicked those inferred from the mapped deposits. We modeled two categories of pyroclastic flows modeled for the level I and level II events. Level I pyroclastic flows correspond to small but more frequent block-and-ash flows that remain on the main cone. Level II flows correspond to more widespread flows from catastrophic eruptions with an approximate 4,000-year repose period. We developed hazard maps from simulations based on a National Imagery and Mapping Agency (NIMA) DTED-1 DEM with a 90 m grid and a vertical accuracy of ±30 m. Because realistic visualization is an important aid to understanding the risks related to volcanic hazards we present the DEM as modeled by FLOW3D. The model shows that the pyroclastic flows extend for much greater distances to the east of the volcano summit where the topographic relief is nearly 4,300 m. This study was used to plot hazard zones for pyroclastic flows in the official hazard map that was published recently. 相似文献
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Landslides as secondary seismic effects are causing some patterns of soil failure that are often considered among the most destructive ones. In fact, the impact from triggered landslides has sometimes exceeded damage directly related to strong shaking and fault rupture. The objective of this research study is landslide hazard and risk assessment considering different water saturation and earthquake scenarios, for a selected area in a sub-urban hilly part of Skopje—the capital of Macedonia. The final product is represented by digital maps of expected permanent displacements for a defined earthquake scenario, in different water saturation conditions of the instable soil layer. Qualitative landslide risk assessment is performed taking into consideration the exposure map of the habitants and local road of the area. As to the target area, it can be concluded that it has the potential for instability that, under certain scenarios, could result in economic and social damage (vulnerability of individual houses, vulnerability of infrastructure and alike). The results from this study referring to potentially affected population and infrastructure present solid base for preventive mitigation activities for reducing the consequences of geotechnical hazards in Skopje City associated with earthquakes. 相似文献
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Seismic Sequence in Carbonate Rocks By Vibrational Liquefaction 总被引：16，自引：0，他引：16
Qiao Xiufu Song Tianrui Gao Linzhi Peng Yang Li Haibing Gao Mai Song Biao Zhang QiaodaInstitute of Geology Chinese Academy of Geological Sciences Beijing 《《地质学报》英文版》1994,68(3)
On the basis of the records of strong seismic events taking place in soft carbonate sediments, a new seismic sequence system of vibrational liquefaction is established, which consists of a series of units, such as escaped structure of micrite veins and liquefied deformation formed in the period of seismic liquefaction, land subsidence structure after liquefaction, tsunamic hummocky and turbidite produced by seismic events, This sequence is a generalization and summation of field observation in vast areas, which shows the whole process of a strong seismic event and provides an unified theoretical explanation. The pattern of the seismic sequence by vibrational liquefaction provides one of correlation standards for geologists in the field to discriminate events in carbonate sequences. Based on the pattern of seismic sequence, the authors first advance a new conception of the Palaeo-Tanlu (Tancheng-Lujiang) Zone and discuss primarily its geological significations. 相似文献
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FanYunxiao LuoYun ChenQingshou 《中国地质大学学报(英文版)》2004,15(1):115-117
The effect of hazard was determined by the dangerous degree of hazard factor-environment and the vulnerable degree of sustaining body. The research into the latter is of importance for the hazard theory and the formation of laws on the mitigation of natural hazards. The way to evaluate the vulnerable degree is the foundation of and the key to the research. In this paper, the extenics model is established to do this job. 相似文献