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采用Ｍｓ和ＭＬ震级表对Ｖａｒｏｔｓｏｓ和Ｌａｚａｒｉｄｏｕ（１９９１）宣称成功的２２个希腊地震预报作了评估。如果我们假定预报的震级为Ｍｓ（预报的震级表在电报中未指明），用震中初步测定目录（ＰＤＥ）估算地震活动性，我们发现有７４％是虚报的（它们并不和某一指定的地震相关），９％偶然相关（任何一个或更多地震的随机概率ｐ〉５０％），以及１７％是不确定的（０．１５〈ｐ〈０．４０），没有什么成功预报其置信水平 相似文献
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多次强震单个发震概率的预测 总被引：1，自引：0，他引：1
本文提出了应用复杂记忆概率预测模型，对预测时段内发生多次地震的各次概率的计算方法。对华北北部地区（３９°─４１°Ｎ，１１４°─１１７°Ｅ）１９９５年至２００５年１０年内发生６级以上地震的概率进行了预测，结论是发生一次大于６级地震的概率为０．８５；在一定的假设条件下计算第一次地震后发生第二次６级以上地震的概率为０．２４；第三次６级以上地震的发生概率为０．０１。 相似文献
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据美国中部和东部地震台网资料，１７２７－１９８２年的地震目录和古地震资料的分析表明：今后３０年发生破坏性地震（Ｍ≥６．０）的泊松概率为中到高水平（０．４－０．６）。若考虑到地震波衰减的差异，可以认为，美国中部和东部今后３０年内发生破坏性地震的概率约为加州地震的２／３，但造成的破坏面积和社会影响是同样严重的。 相似文献
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由观测复发间隔得到的经验地震概率 总被引：3，自引：0，他引：3
给定断层段在前面一次破裂后某一特定时间Ｔ发生破裂的概率Ｐ，可由观测到的该断层段上复发间隔的样本作经验性的评估。假设的全部条件是特定时间段内破裂的概率与该断层段上所有破裂轮回的概率相同。假定观测到的ｎ个复发间隔中有ｍ个与前面一次地震后段Ｔ内发生破裂的轮回相应。新的一次轮回中破裂也落在最近一次地震后时间段Ｔ内的概率密度由β分布Ｐ（ｐ│ｍ，ｎ）＝｛（ｎ＋１）！／［ｍ！（ｎ－ｍ）！］｝ｐ＾ｍ（１－ｐ）＾ｎ 相似文献
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本文采用大森公式ｎ（ｔ）＝Ｋ／（ｔ＋ｃ）＾ｐ求解Ｋ、ｃ、ｐ三个参数，对云南１９６５年以来７１个地震序列进行研究。确定Ｐ＝０．８为前兆震群和正常震群的判定指标。利用Ｋ、ｃ、ｐ三参数计算序列理论曲线得到晚期强余震前差残曲线超出两倍均方差的结果。 相似文献
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地城发生非稳态泊松过程和中长期概率预测研究 总被引：4，自引：1，他引：3
在描述事件非稳态泊松过程的基本统计特征及其与稳态泊松过程判别的基础上,将非稳态泊松过程应用在华北地震区分渭带和华北平原地震带的中长期地震预测研究。研究表明,假定未来几百年间,汾渭带和华北平原带的强震（Ｍ≥７．０）活动,将重现上一次地震轮回的非稳态泊松时间过程,那么,在２０１０年前它们发生一次７级大地震的累计概率分别为０．２６（不确定性范围：０．０６￣０．５０）在０．４（不确定性范围：０．００￣０． 相似文献
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在描述事件非稳态泊松过程基本统计特征的基础上,将非稳态泊松过程应用在华北地震区汾渭带和华北平原地震带的中长期地震预测研究中。研究表明,假定未来几百年间,汾渭带和华北带的强震（Ｍ≥７．０）活动将重现上一次地震轮回的非稳态泊松时间过程,那么,在２０１０年前发生一次７级地震的累计概率分别为０．２６（不确定性范围为０．０６￣０．５０）和０．０４（不确定性范围为０．００￣０．１３）。它们明显地低于按稳态泊松 相似文献
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东地中海地区最近3次强震的余震衰减 总被引：1，自引：0，他引：1
对东地中海地区最近３次强城的余震序列进行了研究。这３次强震分别是：１９９５年１１月２２日Ｍｗ＝７．１地震、１９９３年８月３日ＭＬ＝５．８地震和１９９６年１０月９日ＭＷ＝６．８地震。前两次地震发生在亚喀巴湾,最后一次发生在塞浦路斯西南海岸的近岸。修正的大森公式对所有事件余震活动的衰减都给出了很好的拟合。亚喀巴湾两个序列的ｐ值相对较低（１９９３年,ｐ＝０．９０;１９９５年,ｐ＝０．７５）,这反映了余震 相似文献
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一种计算中小地震地震矩的简易方法 总被引：1，自引：0，他引：1
从Ｂ．Ａ．Ｂｏｌｔ博士得到一个关系式出发，采用一种新的量值转换方法，能够较方便地求得各中小地震的地震矩；并且利用江苏地区的ＤＤ－１地震仪的模拟记录资料，得到了江苏及其邻近地区１．０≤ＭＬ≤４．０的中小地震的地震矩Ｍ０（单位为１０＾０７Ｎ·ｍ）与震级ＭＬ的统计关系式：ｌｏｇＭ０＝（１．７６±０．１１）ＭＬ＋（１５．５９±０．２８）。 相似文献
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Robin K. McGuire 《地震工程与结构动力学》1977,5(3):211-234
The calculation of design spectra for building sites threatened by seismic ground motion is approached by considering the maximum responses of linearly elastic oscillators as indicators of ground motion intensity. Attenuation functions describing the distribution of response as a function of earthquake magnitude and distance are derived using 68 components of recorded ground motion as data. With a seismic hazard analysis for several hypothetical building sites, the distributions of maximum oscillator responses to earthquakes of random magnitude and location are calculated, and spectra are drawn to indicate the maximum responses associated with specified probability levels. These spectra are compared to design spectra calculated from published methods of amplifying peak ground motion parameters. The latter spectra are found to be inconsistent in terms of risk for building sites very close and very far from faults. A ground motion parameter defined to be proportional to the maximum response of a 1 Hz, 2 per cent damped linearly elastic oscillator is investigated; this parameter, in conjunction with peak ground acceleration, is found to lead to risk-consistent design spectra. Through these two parameters, a design earthquake magnitude and design hypocentral distance are defined, for a specified building site and risk level. The use of these parameters in the seismic hazard mapping of a region is illustrated. 相似文献
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地震发生后，针对能够快速预测震中附近的烈度分布情况的问题，首先对632次地震触发的台站进行筛选，对2 231个台站触发后20 s内有效的7个地震动参数以及震级和震源距的信息进行提取，并利用人工神经网络对所选数据样本进行训练，建立三种有效的预测模型。研究结果显示模型一所选的输入参数为7个，不利用震源参数，在预测中有着较好的时效性，从第1 s到20 s,预测的平均烈度差值逐渐减小到0.45;模型二所选的输入参数为8个，利用了震源距信息，可以用于烈度级别的预测，预测的平均烈度差值逐渐减小到0.36;模型三所选的输入参数为9个，预测结果较好，可用于震后烈度场的实时预测，平均烈度差值逐渐减小到0.31。利用提出的3种模型对两次地震事件进行烈度预测，预测烈度差值取整后分别有95%和76%以上在1以内，有着较好的结果，可以用于地震预警当中。 相似文献
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我国新的地震区划图(1990年版)是采用地震危险性慨率分析方法编制的。该图给出的是场点地震烈度值,该值在50年内被突破的概率为0.1。人们普遍关注该图与我国曾经编制的地震区划图(1957年版,1977年版)的区别,该图超越概率概念的内含和外延以及超越概率水平为什么采用50年超越概率0.1。本文围绕这些问题进行了讨论。分析结果表明,前两张地震区划图编图的基本着眼点都是地震预测,而新的地震区划着眼于场点的地震动预测。新的地震区划图是按场点地震危险性分析方法给出的,它所表示的地震危险性只能针对具体的场点,不能完全反映区域的地震危险性特征。而弄清场点地震危险性和区域地震危险性的差异是正确进行区域防灾对策的基础。作者希望这些讨论能对正确使用新的地震区划图有所裨益。 相似文献
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利用《中国地震动参数区划图》采用的地震动参数衰减关系,以及《中国地震动参数区划图》中地震动峰值加速度和地震动加速度反应谱特征周期反推不同设防烈度和设计地震分组对应的震级和震中距,再根据《建筑抗震设计规范》中各设防水准的峰值加速度确定对应的震级和震中距,进而根据地震动强度包线参数与震级和震中距关系计算地震动强度包线参数的取值,为基于强度包线函数生成人工地震动提供参考,并讨论强度包线参数的取值规律：(1)随着设防烈度的提高,加速度时程曲线上升段持续时间t1和平稳段持续时间ts减小,下降段衰减指数c增大;(2)随着地震水准和设计地震分组的提高,加速度时程曲线上升段持续时间t1和平稳段持续时间ts增加,下降段衰减指数c减小;(3)在生成人工地震动时,除考虑峰值加速度和设计地震分组影响外,还需要考虑设防烈度影响。 相似文献
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Ground-motion prediction equations for the intermediate depth Vrancea (Romania) earthquakes 总被引：2，自引：1，他引：1
Vladimir Sokolov Klaus-Peter Bonjer Friedemann Wenzel Bogdan Grecu Mircea Radulian 《Bulletin of Earthquake Engineering》2008,6(3):367-388
We present the regional ground-motion prediction equations for peak ground acceleration (PGA), peak ground velocity (PGV),
pseudo-spectral acceleration (PSA), and seismic intensity (MSK scale) for the Vrancea intermediate depth earthquakes (SE-Carpathians)
and territory of Romania. The prediction equations were constructed using the stochastic technique on the basis of the regional
Fourier amplitude spectrum (FAS) source scaling and attenuation models and the generalised site amplification functions. Values
of considered ground motion parameters are given as the functions of earthquake magnitude, depth and epicentral distance.
The developed ground-motion models were tested and calibrated using the available data from the large Vrancea earthquakes.
We suggest to use the presented equations for the rapid estimation of seismic effect after strong earthquakes (Shakemap generation)
and seismic hazard assessment, both deterministic and probabilistic approaches. 相似文献
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Mathilde B. Sørensen Dietrich Stromeyer Gottfried Grünthal 《Soil Dynamics and Earthquake Engineering》2010
The use of shake maps in terms of macroseismic intensity in earthquake early warning systems as well as intensity based seismic hazard assessments provides a valuable supplement to typical studies based on recorded ground motion parameters. A requirement for such applications is ground motion prediction equations (GMPE) in terms of macroseismic intensity, which have the advantages of good data availability and the direct relation of intensity to earthquake damage. In the current study, we derive intensity prediction equations for the Vrancea region in Romania, which is characterized by the frequent occurrence of large intermediate depth earthquakes giving rise to a peculiar anisotropic ground shaking distribution. The GMPE have a physical basis and take the anisotropic intensity distribution into account through an empirical regional correction function. Furthermore, the relations are easy to implement for the user. Relations are derived in terms of epicentral, rupture and Joyner–Boore distance and the obtained relations all provide a new intensity estimate with an uncertainty of ca. 0.6 intensity units. 相似文献
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Hu-Shuan Wang 《地震学报(英文版)》1993,6(3):705-712
Artificial Neural Network (ANN) model of computation based on mathematical model of neural processes is applied to establish
an intelligent computing network from seismic intensity to peak ground parameter instead of the conventional statistical relationship
in this paper. For a give seismic intensity rating, the network formed with actual strong ground motion records directly produces
the corresponding peak ground parameters and the effects of earthquake magnitude and epicentral distance are included. The
computed results of the network trained with a number of strong motion records in the West America show that such networks
have obtained good conversion relationship from seismic intensity to peak ground parameters.
The Chinese version of this paper appeared in the Chinese edition ofActa Seismologica Sinica,15, 208–216, 1993. 相似文献
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Ludovica Elefante Fatemeh JalayerIunio Iervolino Gaetano Manfredi 《Soil Dynamics and Earthquake Engineering》2010
The results of seismic hazard disaggregation can be used to assign relative weights to a given ground motion record based on its corresponding magnitude, distance and deviation from the ground motion prediction model (epsilon) in order to make probability-based seismic assessments using non-linear dynamic analysis. In this paper, the implications of using the weighted ground motion records are investigated in terms of the mean annual frequency of exceedance of the critical component-based demand to capacity ratio in an existing reinforced concrete structure using both the peak ground acceleration and the first-mode spectral acceleration as intensity measures. It is demonstrated how site-specific seismic hazard disaggregation can be used in order to obtain the conditional probability distribution for a relevant ground motion characteristic given the chosen intensity measure. Distinguished by the amount of structural analysis required, two alternative non-linear dynamic analysis procedures, namely the cloud and the stripes method are implemented. The weighted cloud and the weighted stripes methods are then introduced as analysis procedures which modify the structural response to the selected ground motion records by employing the information provided from the seismic hazard analysis. It is demonstrated that the resulting annual frequencies based on weighted records are comparable to those obtained by using vector-valued intensity measures, while requiring less computational effort. 相似文献