河南小浪底水库库区地震剪切波分裂研究  

Seismic Shear-wave Splitting of Henan Xiaolangdi Reservoir Region

作　　者：李欣波[1] 吴鹏[1] 杨凡[2] 贾华[1] 赵长红[1] LI Xinbo;WU Peng;YANG Fan;JIA Hua;ZHAO Changhong(Handan Central Seismic Station,Hebei Earthquake Agency,Handan 056001,China;Earthquake Agency,Shijiazhuang 050021,China)

机构地区：[1]河北省地震局邯郸中心台,河北邯郸056001 [2]河北省地震局,石家庄050021

出　　处：《华北地震科学》2021年第1期42-48,共7页North China Earthquake Sciences

基　　金：2017年河北省地震科技星火计划项目(DZ20170509038)。

摘　　要：采用河南小浪底水库数字地震台网2009—2016年的地震观测资料,结合双差重定位结果,利用剪切波分裂系统分析方法,获得了小浪底水库库区8个数字地震台站的剪切波分裂参数。研究表明,小浪底库区地震主要分布在库区中段的石井河断层附近,呈团状散布;该区域的剪切波快波平均偏振方向为100.4°±45.0°,慢波平均时间延迟为(2.87±1.13)ms·km^(-1);研究区快波偏振方向与华南地块主压应力场方向一致性较好,区域内多数台站快波偏振方向与附近断层走向平行,慢波时间延迟与华北地块的研究结果相当。Collecting the seismic data from 2009 to 2016 recorded by Henan Xiaolangdi Reservoir Digital Seismic Network,and combining with the results obtained by Double-Difference Hypocenter Locations,this study has obtained the S wave splitting parameters of 8 digital seismic stations distributed in the Xiaolangdi Reservoir region using the SAM method.The results show that the earthquakes occurred in the Xiaolangdi reservoir area are mainly distributed near the Shijing River fault,which is located in the middle of the reservoir area.The dominant polarization direction of the fast shear wave is 100.4°±45.0°and the average time delay of the slow shear wave is(2.87±1.13)ms/km.The dominant polarization direction is consistent with the direction of the regional principal compressive stress of the South China Block.The dominant polarization direction of the fast shear wave of most stations in the region is consistent with the fault strike of the region.The slow wave time delay is equivalent to the results obtained from the North China Block.

关 键 词：小浪底水库 地壳各向异性 剪切波分裂 快剪切波偏振方向 

分 类 号：P315.31[天文地球—地震学]