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1.
The seismic hazard assessment of the Dead Sea rift, Jordan   总被引:1,自引:0,他引:1  
The Dead Sea fault system and its branching faults represent one of the most tectonically active regions in the Middle East. The aim of this study is to highlight the degree of hazards related to the earthquake activities associated with the Dead Sea rift, in terms of speculating the possible future earthquakes. The present investigation mainly is based on available data and vertical crustal modeling of Jordan and the Dead Sea model for the Dead Sea basin with particular emphasis of the recent earthquake activities, which occurred on December 31st, 2003 (Mc = 3.7), February 11th, 2004 (strongest Mc = 4.9 R), and March 15th, 2004 (Mc = 4). The present research examines the location of the strong events and correlates them with the various tectonic elements in the area. The source mechanism of the main shock and the aftershock events is also examined. The analyses were based on the available short period seismogram data, which was recorded at the Natural Resources Authority of Jordan, Seismological Observatory. The seismic energy appears to have migrated from the south to the north during the period from December 31st up to March 12th, where the released seismic energy showed a migration character to the southern block of the eastern side of the Dead Sea, which led the seismic event to occur on March 15th.  相似文献   
2.
地震与核爆识别的小波包分量比方法   总被引:20,自引:5,他引:20  
频谱分析法在核爆与地震识别中具有广泛的应用.但是频谱分析方法是稳态方法,即使采用Gabor变换,也因时-频窗口形状不变而分辨串较低.为提高时-频分辨率,本文将小波变换理论用于乌鲁木齐台记录的地震与核爆事件的分析,并提出了识别核爆和天然地震的小波包分量比判据.通过对加拿大黄刀地震台记录的印度地下核爆的分析,进一步验证了小波包分量比判据对核爆和地震的识别具有较高的识别效率.结果表明:对于地震信号,其小波包分量比U03/U1一般都大于1.0,而对于核爆信号,比值U03/U13一般都小于1.0.  相似文献   
3.
新疆天山地区地下流体地震前兆研究的现状与发展前景   总被引:6,自引:8,他引:6  
王道 《内陆地震》1995,9(2):137-149
系统地介绍了新疆天山重点震监视区下流体观测网,及其地质构造环境和地下水的成因类型,总结了20年来地下流体地震前兆探索与地震前兆探索与地震预报研究的基本经验和成果。  相似文献   
4.
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   
5.
    
After the occurrence of the 26 September 1997 earthquake in Umbria–Marche an extensive survey was performed to individuate surface effects induced by the ground motion. Several types of effects occurred on bedrock, calcareous debris and sandy-clay deposits. Shallow soil slides and dry debris slides were mapped by field survey and aerial photograph interpretation in the epicentral area close to Nocera Umbra. This gave the opportunity for testing the prediction maps that can be obtained with the use of empirical laws, proposed by several authors, based on a simple method (Geotechnique 15(2) (1965) 139). Accelerometric records from the permanent and mobile seismic network of the Seismic Survey of Italy have been processed and interpolated to obtain strong ground motion parameters at each site, e.g. Peak Ground Acceleration, Spectral Intensity, Arias Intensity, etc. The different predictions have been tested with the real landslide data to verify their performances. Some of the proposed methods explain quite well the behaviour of slopes during the application of a time history and can therefore be employed for future landslide hazard zonation.  相似文献   
6.
为寻求更适合天绘一号卫星影像的分割方法,文章采用均值偏移分割、分水岭分割、数学形态学分割、连通分量分割4种图像分割方法对天绘一号卫星影像进行分割实验,并从视觉和定量两方面对分割结果进行评估.结果表明:均值偏移方法的分割质量更佳,且分割结果更有利于提升后续处理的效率;几何形态较规则、质地较均一、复杂度较低的地物类型分割质量较高,反之则较低.  相似文献   
7.
Evaluation of seismic ground motion induced by topographic irregularity   总被引:1,自引:0,他引:1  
Results of an extensive numerical study on the 2D scattering of seismic waves by local topography are presented. The investigation has been conducted using the direct boundary element method. Several types of topography (slopes, canyons and ridges) are considered. The influences of some key parameters, such as exciting frequency and geometry of the irregular feature, on surface ground motion are studied in detail. It is found that local topographic conditions play an important role in the modification of seismic ground motion at the irregular feature itself and its neighbourhood. The present results can be considered to be useful from the viewpoint of earthquake engineering and seismology.  相似文献   
8.
结合3G智能手机小巧易携带、可随时随地上网,配备先进的软硬件系统,可根据需要开发、安装应用软件,功能越来越强大等优点,以中兴U880为例,介绍3G智能手机存地震监测预报工作中的实际应用。  相似文献   
9.
    
Earthquake-induced slope stability is evaluated by the force-equilibrium method in engineering practice. This method provides a safety factor against initiating failure or displacement according to the Newmark model along a fixed slip surface but it cannot evaluate failure deformations after failure occurs. An energy approach is proposed as an alternative means for evaluating slope failures and subsequent flow deformations. The driving energy for slope displacement is considered to be the earthquake energy and the gravitational potential energy. As a first step in the research, an energy balance is formulated for the model of a rigid block resting on an inclined plane. Then, an innovative model test is developed, in which the energy balance in a sliding slope is measured on a shake table. The earthquake energy used for the slope failure can be successfully quantified in the test and its contribution to displacement is discussed in the light of the energy balance established for the block model.  相似文献   
10.
王斌  梁雪萍  周健 《华南地震》2008,28(3):118-126
对盐城地区地震活动概况进行了背景性分析,从该地区地震地质构造背景人手,阐述了影响盐城地区地震活动的主要断裂构造.对研究区域内的地震活动空间、时问分布特征进行了探讨,并分析了盐城地区的地震灾害特点。  相似文献   
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