2009年7月9日姚安M_S6.0地震破裂方向性研究  

Rupture Directivity of the July 9,2009 Yao'an M_S6.0 Earthquake

作　　者：施春辉 何骁慧 倪四道[2] Shi Chunhui;He Xiaohui;Ni Sidao(School of Earth and Space Sciences, University of Science and Technology of China, Hefei 230026, China;Institute of Geodesy and Geophysics, Chinese Academy of Sciences, Wuhan 430077, China)

机构地区：[1]中国科学技术大学地球和空间科学学院,合肥市金寨路96号230026 [2]中国科学院测量与地球物理研究所,武汉430077

出　　处：《中国地震》2018年第2期293-302,共10页Earthquake Research in China

基　　金：国家自然科学基金(41461164003)资助

摘　　要：2009年7月9日19时19分,云南姚安发生M_S6.0地震。10日17:02、13日00:01又相继发生M_S5.2、M_S4.7地震。利用近震CAP方法反演震源机制解发现,此次地震震源破裂方式以走滑为主,主震震源机制解2个节面走向分别为203°、295°。已有的考察资料尚未显示活动,故难以确定实际发震面。为此,采用相对质心震中确定破裂方向性的方法,利用主震与参考地震之间的P波到时差和CAP反演输出的波形时移,计算得到姚安地震起始震中与质心震中间的差异,推断震源机制解中走向为295°的节面为实际发震面,并对定位误差、发震时刻不准确以及机制解差异等因素进行了分析,发现这些因素对确定发震断层影响不大。The Yao＇an,Yunnan M_S6.0 earthquake occurred at 19： 19 of July 9,2009. At 17： 02 of July 10 and 00： 01 of July 13,the M_S5.2 and M_S4.7 earthquakes occurred. We applied the CutAnd-Paste（CAP） method to determine the focal mechanism,and found the earthquake is a strikeslip event,with two nodal planes striking 203 degrees and 295 degrees. Active faults have not been found in previous regional geological survey,so it is difficult to determine the seismogenic fault. We use the relative centroid location method to determine the earthquake ＇s rupture directivity,and found that the nodal plane with the strike of 295~° is the ruptured plane. We also investigated the result＇s robustness against the error of location,original time and focal mechanism,and found the resolved rupture directivity is stable.

关 键 词：破裂方向 质心震中 姚安地震 

分 类 号：P315[天文地球—地震学]