2020年云南东川M_(L)4.2地震序列精定位研究  

Accurate Location of the 2020 Dongchuan,Yunnan M_(L)4.2 Earthquake Sequence

作　　者：高方鸿 刘志坤[1] 耿传涛 GAO Fanghong;LIU Zhikun;GENG Chuantao(School of Geophysics and Information Technology,China University of Geosciences,Beijing 100083,China)

机构地区：[1]中国地质大学(北京)地球物理与信息技术学院,北京100083

出　　处：《地震研究》2022年第1期48-53,共6页Journal of Seismological Research

基　　金：国家自然科学基金(41774062)资助.

摘　　要：利用云南东川地区10个宽频带流动台站的连续波形数据,采用基于深度学习的自动震相拾取方法和震相关联技术,对2020年东川M_(L)4.2地震序列分别进行绝对定位和相对定位,获得了该地震序列的高精度地震定位结果,得到东川M_(L)4.2地震序列的212个余震事件,约为中国地震台网目录给出的余震数目的5倍,丰富了M_(L)≤3.0余震;精定位结果表明东川M_(L)4.2主震震源深度为5.19 km,余震震源深度集中在3~6 km,余震序列分布长轴呈NNE向展布;此次地震发生在小江断裂带西支,发震构造与乌龙拉分盆地的构造演化有关。Selecting the continuous waveform data from 10 temporary broadband seismic stations in Dongchuan,Yunnan Province,and using the automatic seismic phase detection and correlation based on deep learning,we conduct absolute and relative locations of the July 8th,2020 Dongchuan M_(L)4.2 earthquake sequence,and obtain high-resolution results:the M_(L)4.2 earthquake sequence contains 212 events,about five times of the events from the catalogue of China Earthquake Networks Center,enriching the M_(L)<3.0 aftershocks.The focal depth of the M_(L)4.2 mainshock is 5.19 km and the aftershock sequence concentrates in the depth of 3—6 km.The Long axis of the aftershock zone is in the NNE direction.The earthquake sequence occurs in the west branch of the Xiaojiang Fault Zone and its seismogenic structure may be related with the tectonic evolution of the pull-apart Wulong Basin.

关 键 词：地震定位 微震检测 小江断裂带 双差定位法 拉分盆地 东川M_(L)4.2地震 

分 类 号：P315.73[天文地球—地震学]