2015年11月22日广东徐闻M_L 4.2地震震源机制解及精定位分析  

Focal mechanism solution and accurate location of Xuwen M_L 4.1 earthquake in Guangdong Province on Nov.22,2015

作　　者：徐晓枫[1] 王惠琳[1] 胡久常[1] 宋秀青[2] 孙佩雯[1] Xu Xiaofeng;Wang Huilin;Hu Jiuchang;Song Xiuqing;Sun Peiwen(Earthquake Administration of Hainan Province, Haikou 570203, China;Earthquake Administration of Shanghai Municipality, Shanghai 200062, China)

机构地区：[1]海南省地震局,中国海口570203 [2]上海市地震局,中国上海200062

出　　处：《地震地磁观测与研究》2017年第2期1-6,共6页Seismological and Geomagnetic Observation and Research

基　　金：海南省地震局青年科学基金项目(项目编号:201606)

摘　　要：基于海南地震台网数字波形资料,采用CAP方法对2015年11月22日广东徐闻M_L 4.2地震反演震源机制解,计算得出节面Ⅰ参数:走向110°,倾角84°,滑动角-158°;节面Ⅱ参数:走向18°,倾角69°,滑动角-5°。推断为1次走滑为主兼有正断性质的破裂,与铺前—清澜断裂属于走滑正断的运动特征较为吻合。对2000年1月—2016年6月主震周边地区(19.3°—20.6°N,110.0°—111.0°E)M_L1.0以上183次地震进行双差精定位分析,得到146次地震的重定位结果。结果显示:震源深度分布不再仅局限于10 km附近,而是呈垂直带状分布,与雷琼地区新构造运动主要以垂直差异性活动为主的活动特征相吻合。The Xuwen ML4.2earthquake occurred on July31,2016.Base on the records of Hainan Earthquake Network,we obtained the focal mechanism of the earthquake with the“cut and paste”(CAP)method.The result shows:the strike,dip and rake angles of nodal plane I are110°,84°and-158°,respectively;Those of other nodal plane are18°,69°and-5°.It is concluded that the seismogenic fault of Xuwen ML4.2earthquake is a strike-slip fault with normal type.This is in agreement with the movement characteristic of the Puqian-Qinglan fault which belongs to the strike-slip fault.Using the double difference location method,183ML≥1.0earthquakes from January2000to June2016are relocated.The relocating results of146earthquakes are obtained.The result shows that the source distributions are no longer confined to the10km,but is a vertical zonal distribution.This is consistent with the activity characteristic of the new tectonic movement which is mainly vertical difference activity in Leiqiong region.

关 键 词：CAP方法 双差定位法 震源机制解 震源深度 地震构造 

分 类 号：P315.33[天文地球—地震学]