Relocation of Microearthquakes in Beijing and Its Neighboring Areas and Its Tectonic Implications   总被引：1，自引：0，他引：1  

Wang Suyun  Xu Zhonghuai  Yu Yanxiang  and Huan WenlinInstitute of Geophysics  SSB  Beijing  China 《中国地震研究》1996,(1)

The 348 microearthquakes that occurred in Beijing and its neighboring areas(39°-41°,114°-117°E)during 1979 to March of 1992 are relocated in this study.Precision of hypocenter locations is improved by rechecking and supplementing readings of arriving times of the seismic phases used,testing and selecting the appropriate crustal model,and modifying the computer program.After the relocation,the number of earthquakes with focal depth determination has been increased to 313 from the previous 132.The overall average RMS residual of the observational arrival times has been reduced to 0.45±0.18 s from the previous value of 0.80±0.40 s.Nearly 10% of the relocated hypocenters,which are mostly in border regions of the area covered by the Beijing Telemetered Seismic Network,have been shifted more than 10 km.Epicenters of the relocated earthquakes are concentrated in the intermountainous basins,such as the Huai'an,Xuanhua,Huailai,and Zhuolu basins,and are related with the basin boundary faults between mountai  相似文献   

Variation of the Load/Unload Response Ratio Before the Main Shocks of the Reservoir-Induced Earthquakes     

Chen Xuezhong  Yin XiangchuInstitute of Geophysics  SSB  Beijing  ChinaCenter for Analysis  Predicuon  SSB  Beijing  China 《中国地震研究》1996,(2)

In this paper, the theory of the load/unload response ratio is applied to the prediction of the reservoir-induced earthquakes, and variation of the load/unload response ratio Y preceding the occurrence of main shocks of the reservoir-induced earthquakes in Xinfengjiang, Foziling, Danjiangkou, and Shenwo. The results show that the load/unload response ratio Y rises evidently prior to the main shocks.  相似文献   

Investigation on the Load/Unload Response Ratio With Coda Q-1 as Response     

Chen Xuezhong  Yin Xiangchu  Aki K  Ouyang H  Jin A.  Song Zhiping  and Wang YucangCenter tor Analysis  Prediction  SSB  Beijing  ChinaSouthern California Eanhquake Center  University of Southern California  Los Angeles  USAInstitute of Geophysics  SSB  Beijing  China 《中国地震研究》1996,(4)

The load/unload response ratio YQ with the geophysical parameter coda Q-1 of the crust as response is denned in this study.The variation in YQ-1 before and after the Northridge earthquake of January 17,1994(California)has been investigated by using the data of coda Q-1 with frequencies of 1.5,3.0,6.0,12.0,and 24.0 Hz in the Southern California from 1987 to 1994.It can be found that YQ-1 for coda waves with all frequencies,the frequency of 12.0 Hz excluded,ascended to a certain extent prior to the occurrence of the rnainshock and returned to normality after the main shock.  相似文献   

The Temporal Variation of LURR in Kanto and Other Regions in Japan and Its Application to Earthquake Prediction     

Yin Xiangchu  Chen Xuezhong  Song Ziping  and Wang YucangCenter for Analysis  Prediction  SSB  Beijing  China Institute of Geophysics  SSB  Beijing  China 《中国地震研究》1996,(4)

The temporal variation of LURR(y)for Kanto,Wakayama,and Hugo regions in Japan has been calculated and analysed.The LURR(y)values are significantly higher than 1 before the occurrence of all earthquakes with magnitude M≥6.0 in the Kanto region during the last two decades and the Kobe earthquake(1995-01-17).These results suggest that LURR theory is available for Japan.Recently they-value for Wakayama region has been near 1,while the y-value is remarkably larger than 1 for nearly two years for Kanto.According to these results,it is predicted that a strong earthquake with magnitude of about 6.0 could occur in 1 year or a little longer for in Kanto region or its adjacent regions,but there is little possibility for the Wakayama region.  相似文献   

火山震动特征及其动力学研究进展     

安镇文  叶正仁 《地震地磁观测与研究》1997,18(1):9-17

结合国内外资料，介绍了近年来火山震动的非线性动力学研究进展，并且讨论了预测火山活动的某些综合方法。  相似文献   

A uniform catalog of earthquakes for seismic hazard asesment in Iran   总被引：6，自引：0，他引：6  

高孟谭  陈运泰  王健 《地震学报(英文版)》1997,10(6):713-726

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用于速度图象重建的层析成象法   总被引：35，自引：15，他引：35       下载免费PDF全文

刘福田  李强 《地球物理学报》1989,32(1):46-61

本文提出了一种用于速度图象重建的层析成象法。特别注意到地震学上的ST与医学上的CT的不尽相同之处,并处理了由此引起的困难。与速度图象重建有关的正问题的分析表明,不同频率范围的资料其分辨能力是不同的,因此,区域地震与远震资料的解释应予注意。本文有关速度图象重建的讨论不仅涉及到与成象方法有关的反演理论和方法,还给出了进行数值计算的内存量和运算量的分析。关于重建图象的质量评价,还给出了反演解的可靠性分析,为分辨特性的描述提供了一种既简便又形象直观的方案。 本文的方法与现行主要方法的比较表明:1.本文的方法允许存在速度间断面,有利于揭示不同构造区域的地壳厚度的差异;2.在常用的方法中,作为正问题假定的常速度块同反演结果解释时非常速度块之间不协调。由于我们把给定网格点的速度值的插值函数作为速度的空间函数,这一困难已被解决;3.相对于Aki等的一般方法,本文的内存量节省约一个量级、运算量减少约一半;4.相对于ART类方法本身不能给出成象结果的可靠性分析,本文的方法则具有显著的优点。 作者在分析了天然地震资料的状况之后相信,对充分利用我国地震台网的现有观测资料,本文的方法是有效的。  相似文献   

扬子地台灯影组碳酸盐岩中的硫和碳同位素记录   总被引：17，自引：3，他引：17  

张同钢储雪蕾  张启锐冯连君 霍卫国 《岩石学报》2004,20(3):717-724

扬子地区灯影组的海相碳酸盐岩地层不仅记录了当时海水的碳同位素变化，也保存了海水的硫同位素记录，能够通过测定所提取的微量硫酸盐的硫同位素组成来获得。灯影组碳酸盐岩中微量硫酸盐的δ^34S值大部分在 20.0‰～ 38．7‰之间变化，碳酸盐岩的δ^13C值变化在 0．5‰～ 5．0‰之间。除灯影组顶、底界线处外，δ^34S和δ^13C值总体上变化幅度较小，大体上呈逐渐降低的变化趋势。灯影组碳酸盐岩中连续的硫、碳同位素记录分别反映了同期海水中溶解硫酸盐和碳酸盐的硫、碳同位素的变化特征。灯影组微量硫酸盐和碳酸盐岩的同位素特征，意味着灯影期海洋中具有高的生物产率和有机碳埋藏速率；除了顶底界线处，具有相对稳定的古气候条件和古海洋环境。灯影期海水的δ^34S值和δ^13C值同时呈逐渐降低的变化趋势，可能是由海洋深部水体逐渐氧化所致。  相似文献   

山东仰口地区超高压变质岩混杂带的组成及其构造变形     

方爱民  赵中岩 《岩石学报》2004,20(5):1087-1096

从构造岩石角度将山东青岛仰口地区发育的超高压变质岩混杂带划分为构造整合单元和构造混杂单元两个组成部分，对不同单元的岩性组成及其超高压变质特征进行了描述。着重对不同构造单元中的构造变形期次进行了划分。总结了不同期次构造变形的宏观及微观特征。结合苏鲁超高压变质带在区域上构造变形期次的研究情况，初步提出形成仰口地区超高压变质岩中各种构造形迹的构造模式，并对它们所反映的仰口超高压带形成和折返的构造意义进行了探讨。  相似文献   

高密度电阻率法在城市活断层调查中的应用   总被引：7，自引：3，他引：7  

李清林  张建志  秦建增  黄邦武 《CT理论与应用研究》2003,12(1):1-5

目的 在城市活断层调查中应用高密度电阻率层析成像测量方法。资料和方法 利用电阻率层析成像测量方法，在北京某地的活断层、郑州老鸦陈断层、安阳南断裂等处理进行了地震活断层调查，采用正、反演处理软件进行资料处理和解释。结果 取得了较理想的勘探效果。结论 在城市活断层调查中，电阻率层析成像测量方法是一种十分有效的勘探方法。  相似文献