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本文依据信息量的定量判定方法，从分析地震地质和前兆因子与强震发生的关系出发，对各种因子所能提供的长期或１０年尺度强震危险的信息量作了估计。 相似文献
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时间-震级可预报模式在南北地震带分段危险性评估中的应用 总被引：9，自引：1，他引：8
为了定量评估南北地震带不同段落的长期地震危险性,引入了时间－震级可预报模式。在详细地震复发行为的基础上,沿南北地震带划分了３９个震源区。利用其中２７个震源的多轮回复发资料初步建立起时间－震级可预报统计模型。计算结果表明,不同震源的地震复发表现出较好的时间可预报行为以及相对较弱的震级可预报行为。以时间可预报模型为基础,对所有震源区未来地震的复发概率进行了估算,同时,用震级可预报模型对未来地震的震级作 相似文献
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一种利用贝叶斯最小判别准则估计未来地震危险的新方法 总被引：2，自引：0，他引：2
提出了一种基于最大似然和贝叶斯最小判别准则的新预测方法,它的长处在于对样本数无特殊要求,所以,对低地震活动地区,此模型也能得到与时间有关的稳定的未来强震危险估计。最后,以华北地区为例,说明了本方法的可行性。 相似文献
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《地震研究进展（英文）》2023,3(1):100177
The long-term earthquake prediction from 2021 to 2030 is carried out by researching the active tectonic block boundary zones in the Chinese mainland. Based on the strong earthquake recurrence model, the cumulative probability of each target fault in the next 10 years is given by the recurrence period and elapsed time of each fault, which are adopted from relevant studies such as seismological geology, geodesy, and historical earthquake records. Based on the long-term predictions of large earthquakes throughout the world, this paper proposes a comprehensive judgment scheme based on the fault segments with the seismic gap, motion strongly locked, sparse small-moderate earthquakes, and apparent Coulomb stress increase. This paper presents a comprehensive analysis of the relative risk for strong earthquakes that may occur in the coming 10 years on the major faults in the active tectonic block boundary zones in the Chinese mainland. The present loading rate of each fault is first constrained by geodetic observations; the cumulative displacement of each fault is then estimated by the elapsed time since the most recent strong earthquake. 相似文献
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在强烈地震发生后,会引发建筑火灾等次生灾害,涉及因素较多,传统火灾危险性数学模型忽略了强震后既有建筑发生火灾时不同因素的随机性与模糊性特性,难于建立健全的评估数学模型,导致评估精度低。为解决该问题,通过分析强震后既有建筑火灾影响,用因素模糊数学方法建立强震后既有建筑火灾危险性评估数学模型及评估体系。具体方法是对评估指标体系中各层因素针对上层因素影响进行评分,建立判断矩阵,获取权重。确定隶属度矩阵,获取强震后既有建筑火灾危险性评估的因素集与评语集,构造单因素评判,给评估集中的因素赋予权重,进行一级模糊评估。把一级评估结果当成二级评估的单因素评估,通过模糊数学理论完成对强震后既有建筑火灾危险性的评估,得到综合评估结果。实验结果表明,采用所提模型进行危险性评估,得到结果符合实际情况,与其他模型相比,所提模型评估精度高。 相似文献
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Gian Paolo Cimellaro Fabrizio Ozzello Alessio Vallero Stephen Mahin Benshun Shao 《地震工程与结构动力学》2017,46(6):985-1002
In classical earthquake risk assessment, the human behavior is actually not taken into account in risk assessment. Agent‐based modeling is a simulation technique that has been applied recently in several fields, such as emergency evacuation. The paper is proposing a methodology that includes in agent‐based models the human behavior, considering the anxiety effects generated by the crowd and their influence on the evacuation delays. The proposed model is able to take into account the interdependency between the earthquake evacuation process, and the corresponding damage of structural and non‐structural components that is expressed in term of fragility curves. The software REPAST HPC has been used to implement the model, and as a case study, the earthquake evacuation by a mall located in Oakland has been used. The human behavior model has been calibrated through a survey using a miscellaneous sample from different countries. The model can be used to test future scenarios and help local authorities in situations where the human behavior plays a key role. Copyright © 2017 John Wiley & Sons, Ltd. 相似文献
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利用基于时-空传染型余震序列（Epidemic Type Aftershock Sequence, 简称ETAS）模型的随机除丛法,重新审视了2008年5月12日汶川MS8.0地震前可能存在的长期地震活动异常,研究了川滇地区背景地震活动特征,并评估了当前的强震危险状态.对川滇地区1970年以来的ML3.0以上的背景地震和丛集地震活动的研究结果表明,该地区地震丛集特征明显、时空分布很不均匀、地震序列常有前震事件.直接将概率值作为地震计数的权重,对地震丛集率空间分布图像分析表明,汶川MS8.0地震前,龙门山断裂带中南段存在着长期、大范围的地震丛集率低值区,震前该段处于应力闭锁状态.对川滇地区地震丛集率低值区内背景地震与全部地震的累积次数、b值和新定义的Δb等统计参量的分析表明,龙日坝与龙门山断裂带具有地震活动的关联性,川滇地区当前的强震潜在危险区可能是巧家地区和汶川MS8.0地震破裂尚未穿越的龙门山断裂带南段.此外,还发现b值倾向于反映局部应力场变化,而Δb能较为敏感地给出更大范围应力场的相对变化. 相似文献
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中等地震活动增强作为强震标志的研究 总被引：7，自引：0，他引：7
通过对(1990~1996年)发生在我国大陆及边境地区24次6级以上地震的分析研究表明,80%的强震主震前在震源区及附近有中等地震活动增强的过程。异常表现出共同的基本特征,即长期平静→增强活动→震前平静→发震。震前平静至发震大约经历几个月到2年时间(平均10个月左右),可以作为中短期地震预报判据。用岩石蠕变声发射实验来解释这一现象,可把中等地震活动增强看作是稳态蠕变阶段后期发生的广义前震。 相似文献
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安宁河、 则木河构造区近期强震危险性的概率估计 总被引：5，自引：0，他引：5
2008年5月12日汶川8.0级地震发生后, 作为历史强震多发地段南北地震带中南段的安宁河、 则木河构造区强地震危险性受到广泛关注。 本文在分析安宁河、 则木河构造区强震活动特点的基础上, 利用地震危险性韦布尔概率估计方法, 对该区未来10年内发生6.5级以上强震的累计概率和条件概率进行了计算, 并结合前人针对汶川地震破裂对周边断层产生的库仑应力变化及潜在震源区判定等研究结果, 对该区强地震危险性进行了综合判断。 结果表明, 汶川8.0级地震发生后, 安宁河、 则木河构造区5级以上中强地震似有逐步活跃的趋势; 根据韦布尔概率模型计算得出的该区2021年前发生6.5级以上强地震的概率高达0.93, 条件概率为0.32。 因此, 该构造区, 尤其是区内的冕宁—西昌一带未来10年发生强地震的可能性相对较高。 相似文献
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Jonathan F. Nott 《地球表面变化过程与地形》1992,17(4):361-374
The long-term evolution of streams in the Shoalhaven catchment of southeast New South Wales has been a contentious issue for decades. Several authors have suggested that the Shoalhaven River was captured at the sharp eastward bend near Tallong: this has been used as evidence for the westward migration of the east Australian divide in this area. Other workers, however, have argued that capture did not occur and that the location of the divide has been stable throughout the Tertiary. A vast sheet of sediments which spread across and infill a palaeovalley network cut into a broad undulating plain in the middle Shoalhaven catchment provides a record of stream behaviour since at least the start of the Tertiary. This record shows that the Shoalhaven River and many of its tributaries have maintained almost the same courses since at least the very Early Tertiary. This provides strong evidence against the capture hypothesis. The record further suggests that during the Paleogene these streams were graded to a level within the southeast Australian highlands; their depths of incision thus cannot be used as evidence for the extent of uplift of the southeast Australian highlands during this time. 相似文献
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Djuro Radinović 《Pure and Applied Geophysics》1972,93(1):159-176
Summary A numerical model for the quantitative precipitation forecasting has been formulated. In this model precipitation is computed as a function of the vertical velocity and humidity distribution in the atmosphere. The orographic influence on the vertical velocity was taken into consideration. Further, the relation between vertical velocity and static stability of the atmosphere has been considered and, as an important factor in the condensation process, was introduced into the equation of the model. This numerical model for the precipitation forecasting has been applied in the North Adriactic Sea region, which is characterized by a strong vertical gradient of the specific humidity and pronounced orographic influence. The results achieved show that this model could successfully be used as an objective method in the routine forecasting of the amount of precipitation. 相似文献
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从信息论及贝叶斯模型出发,以长期异常背景为基础,近期异常为依据,在对未来十年Ｒ度的地震趋势进行估计的条件下,预测了河北北部２００５年前强震危险性,给出了区域内强震发生和各裂度概率的空间分布。 相似文献
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中国大陆强震时空关联特征及应用 总被引：4，自引：0，他引：4
根据我国大陆强震成组活动的特征,以强震诱发和成组孕育理论为基础,对我国近30年以来的强震进行At值扫描,并对其作出了系统分析和R值评分,据此对我国地震大形势进行了一定程度的预测。 相似文献
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Mathematical modeling founded on a strong field data base can be a valuable tool for the analysis of ground-water contamination problems. The purposes of this paper are threefold: (1) we demonstrate the dilemma of a knowledgeable ground-water quality regulator whose regulatory decision-making process is confronted with the output of a mathematical model that is based on very limited field test data; (2) we demonstrate a method available to a knowledgeable regulator for assessing approximately a range of possible performances of a contaminated ground-water recovery well field using a range of input data derived from a very limited data base; and (3) we present a strong case for presenting mathematical model outputs as ranges of values rather than as unique solutions. A range is determined by an examination of the level of sophistication of the field data base. Our experience with 12 field sites wherein ground-water contamination has occurred has led us to conclude that field data are seldom, if ever, adequate to defend a unique solution from a mathematical model. Regulatory decisions generally can be reduced to minimization of risks based on the smallest range of model outputs that can be defended on the basis of the field data base. The more limited the field data base, the greater must be the range of defensible model outputs, and consequently, the greater the risk inherent in subsequent regulatory decisions. The knowledgeable regulator can assess the risks in the regulatory decision-making process only if he is able to assess the extent to which the field data base for the mathematical model output reflects state-of-the-art data collection and analysis technologies and methodologies. If an applicant for a permit or license submits a less than adequate data base and concomitantly a broad range of defensible model outputs, he inherently requests that the knowledgeable regulator accept a risk greater than that required if adequate aquifer testing techniques had been employed. 相似文献
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C. Dai X. H. Cai Y. P. Cai Q. Huo Y. Lv G. H. Huang 《Stochastic Environmental Research and Risk Assessment (SERRA)》2014,28(2):167-187
In this research, approaches of interval mathematical programming, two-stage stochastic programming and conditional value-at-risk (CVaR) are incorporated within a general modeling framework, leading to an interval-parameter mean-CVaR two-stage stochastic programming (IMTSP). The developed method has several advantages: (i) it can be used to deal with uncertainties presented as interval numbers and probability distributions, (ii) its objective function simultaneously takes expected cost and system risk into consideration, thus, it is useful for helping decision makers analyze the trade-offs between cost and risk, and (iii) it can be used for supporting quantitatively evaluating the right tail of distributions of waste generation rate, which can better quantify the system risk. The IMTSP model is applied to the long-term planning of municipal solid waste management system in the City of Regina, Canada. The results indicate that IMTSP performs better in its capability of generating a series of waste management patterns under different risk-aversion levels, and also providing supports for decision makers in identifying desired waste flow strategies, considering balance between system economy and environmental quality. 相似文献
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Modern engineering design methods require ground motion time histories as input for non-linear dynamic structural analysis. Non-linear dynamic methods of analysis are increasingly applied in the context of probabilistic risk assessments and for cost-effective design of critical infrastructures. In current engineering practice artificial time histories matching deterministic design spectra or probabilistic uniform hazard spectra are most frequently used for engineering analysis. The intermediate step of generation of response spectra can lead to a biased estimate of the potential damage from earthquakes because of insufficient consideration of the true energy content and strong motion duration of earthquakes. Thus, assessment of seismic risk may seem unrealistic. An engineering approach to the development of three-component ground motion time histories has been established which enables consideration of the typical characteristics of seismic sources, regional ground motion attenuation, and the main geotechnical characteristics of the target site. Therefore, the approach is suitable for use in scenario-based risk analysis a larger number of time histories are required for representation of the seismic hazard. Near-field effects are implemented in the stochastic source model using engineering approximations. The approach is suggested for use in areas of low seismicity where ground motion records of larger earthquakes are not available. Uncertainty analysis indicates that ground motions generated by individual earthquakes are well constrained and that the usual lognormal model is not the best choice for predicting the upper tail of the distribution of the ground motions. 相似文献