2003年1月4日新疆伽师5.4级地震的强震观测与分析   总被引：1，自引：0，他引：1  

艾买提·乃买提  张智强  吕桂林 《内陆地震》2003,17(3):216-221

2003年1月4日新疆伽师县发生了5．4级地震，其宏观烈度为Ⅵ度。布设在伽师县城的强震固定台记录到5．4级主震及1次4．2级余震的加速度，其中一个地震的最大加速度值(水平分量)为66．12gal。初步分析这次强地震运动特性，得出两点结论：(1)强运动记录检验了投入使用的GDQJ-1A型仪器性能良好；(2)加速度时程记录表明垂直向P波初动尖锐、强震持时较长，最长约达7．5s，而水平向P波初动弱、强震持时较短，仅约2．5s。  相似文献   

Large displacement behaviour of a structural model with foundation uplift under impulsive and earthquake excitations     

Giuseppe Oliveto  Ivo Cali  Annalisa Greco 《地震工程与结构动力学》2003,32(3):369-393

This paper considers the dynamical behaviour of a structural model with foundation uplift. The equations of motion of the system considered are derived for large displacements thus allowing for the eventual overturning of the system. The transition conditions between successive phases of motion, derived in terms of the specific Lagrangian co‐ordinates used in the formulation of the equations of motion, present innovative aspects which resolve some previously inexplicable behaviour in the structural response reported in the literature. The dynamical behaviour of the model is considered under impulsive and long‐duration ground motions. The minimum horizontal acceleration impulses for the uplift and the overturning of the system are evaluated in analytical form. The sensitivity of the model to uplifting and to overturning under impulsive excitations is established as a function of few significant structural parameters. Numerical applications have been performed changing either the structural parameters or the loading parameter, in order to analyse several dynamical behaviours and also to validate the analytical results. For earthquake ground motions the results, reported in the form of response spectra, show that linearized models generally underestimate, sometimes significantly, the structural response. Copyright © 2003 John Wiley & Sons, Ltd.  相似文献   

2002年4月5日江西强对流天气过程分析   总被引：1，自引：1，他引：1  

刘芳  刘献耀  李玉芳 《气象与减灾研究》2003,26(2):14-17

运用天气图、T213物理量场、卫星云图及相关的实况资料,综合分析了2002年4月5日08～23时发生在江西中北部的1次罕见的雷雨大风,并伴有局地强降水和冰雹等强对流天气的过程,从而揭示了本次过程的生消成因以及在热力、动力学等方面的基本特征。  相似文献   

基于GIS的强震震例信息管理系统的研制与应用     

国艳  韩绍欣  钱军 《东北地震研究》2003,19(2):68-72

以近年来中、强地震震害资料为基础，采用先进的GIS技术，建立了强震震例信息管理系统。通过该系统可以迅速了解地震的基本参数、地震地质背景、烈度分布以及经济损失等资料。  相似文献   

Glacial isostatic adjustment on 3-D Earth models: a finite-volume formulation   总被引：3，自引：0，他引：3  

Konstantin Latychev  Jerry X. Mitrovica  Jeroen Tromp  Mark E. Tamisiea  Dimitri Komatitsch  Christina C. Christara 《Geophysical Journal International》2005,161(2):421-444

  相似文献   

Estimation of the spatial distribution of ground motion parameters for two recent earthquakes in Japan   总被引：8，自引：0，他引：8  

Khosrow T. Shabestari  Fumio Yamazaki  Jun Saita  Masashi Matsuoka 《Tectonophysics》2004,390(1-4):193-204

A recent development in strong motion instrumentation in Japan provides an opportunity to collect valuable data sets, especially after moderate and large magnitude events. Gathering and modeling these data is a necessity for better understanding of regional ground motion characteristics. Estimations of the spatial distribution of earthquake ground motion plays an important role in early-stage damage assessments for both rescue operations by disaster management agencies as well as damage studies of urban structures. Subsurface geology layers and local soil conditions lead to soil amplification that contributes to the estimated ground motion parameters of the surface. We present a case study of the applicability of the nationally proposed GIS-based soil amplification ratios [J. Soil Dyn. Earthqu. Eng. 19 (2000) 41–53] to the October 6, 2000 Tottori-ken Seibu (western Tottori Prefecture) and the March 24, 2001 Geiyo earthquakes in Japan. First, ground motion values were converted to those at a hypothetical ground base-rock level (outcrop) using an amplification ratio for each 1×1 km area, based on geomorphological and subsurface geology information. Then a Kriging method, assuming an attenuation relationship at the base-rock as a trend component, is applied. Finally, the spatial distribution of ground motion at ground surface is obtained by applying GIS-based amplification factors for the entire region. The correlation between the observed and estimated ground motion values is reasonable for both earthquakes. Thus, the proposed method is applicable in near real-time early-damage assessments and seismic hazard studies in Japan.  相似文献   

台湾与大陆西部地区强震活动的呼应关系     

沈春芳  吴松江  沈健健 《福建地震》2003,(3)

台湾与大陆西部地区同属地槽回返区 ,同处于板块的缝合线上 ,因而两地的地震活动都比较强烈且频繁。根据对有地震记录以来的近 1 0 0多年的资料统计分析 ,表明每当西部地区发生一个或多个 6.8级以上的强震后不久 ,台湾地区必有一个或多个相应震级的强震与之相呼应。这是印度洋板块向北推挤碰撞的作用力与反作用力 ,明显大于太平洋板块对欧亚板块的作用力与反作用力的结果。  相似文献   

一个新的中短期地震预报指标   总被引：2，自引：0，他引：2  

陈学忠!中国北京  丁鉴海!中国北京 《地震》1998,(2)

通过对强震前数年内一定震级档次内的地震活动进行分析 ,提出一个刻划地震孕育过程进入中短期阶段的指标— Cr值。它可以反映岩石本构关系曲线峰值点附近的状态。在对 7次 7级左右强震进行震例研究表明 ,震前 Cr值出现明显高值异常。Cr值达最高值的时间超前地震发生 1～ 3a,多数是在 1 a左右 ,这对中短期地震预报有意义。  相似文献   

现代板块运动的测量和研究：地球物理方法   总被引：8，自引：2，他引：6  

孙付平  赵铭 《地球物理学进展》1998,13(1):1-16

本文简要阐述了用地球物理手段测量和研究现代全球板块运动的理论和方法、现状和发展。结合最新地学板块运动模型ＮＵＶＥＬ－１,着重介绍了最近十几年来全球板块运动的研究进展,对目前存在的问题及未来的发展作了评述。  相似文献   

地震窗方法在新疆伽师强震群短,临预报中的应用   总被引：3，自引：0，他引：3  

敖雪明  王桂岭 《内陆地震》1998,12(4):289-294

系统分析了１９９７年新疆伽师强震群多次中强以上地震前新疆地震窗的短临异常特征,并根据窗口网小震月频异常对伽师强震群首次６级地震作出了较好的短期预报。同时通过分析 阿图什余震窗在其后多次中强地震前出现的小震日频度异常,提取出阿图什余震窗的异常判据和预指标,统计检验结果表明,余震窗方法具有较高临震预报效能。  相似文献