2021年双湖M_(S)5.8地震InSAR同震形变场及断层滑动分布反演  

Coseismic Deformation Field and Fault Slip Distribution of the 2021 Shuanghu M_(S)5.8 Earthquake Revealed by InSAR Data

作　　者：李承涛 李琦[1,4] 谭凯 鲁小飞[1,2,3] LI Chengtao;LI Qi;TAN Kai;LU Xiaofei(Institute of Seismology,CEA,40 Hongshance Road,Wuhan 430071,China;Key Laboratory of Earthquake Geodesy,CEA,40 Hongshance Road,Wuhan 430071,China;Hubei Earthquake Agency,48 Hongshance Road,Wuhan 430071,China;Hebei Key Laboratory of Earthquake Dynamics,465 Xueyuan Road,Sanhe 065201,China)

机构地区：[1]中国地震局地震研究所,武汉市430071 [2]中国地震局地震大地测量重点实验室,武汉市430071 [3]湖北省地震局,武汉市430071 [4]河北省地震动力学重点实验室,河北省三河市065201

出　　处：《大地测量与地球动力学》2022年第2期153-157,共5页Journal of Geodesy and Geodynamics

基　　金：中国地震局地震研究所和应急管理部国家自然灾害防治研究院基本科研业务费(IS201956311);河北省地震动力学重点实验室开放基金(FZ212201);大地测量与地球动力学国家重点实验室开放基金(SKLGED2021-4-1);湖北省自然科学基金(2019CFB555)。

摘　　要：基于Sentinel-1A数据,利用合成孔径雷达差分干涉(DInSAR)技术提取视线向(LOS)同震形变场,利用基于序列蒙特卡罗采样的贝叶斯方法反演发震断层几何参数与断层滑动分布。结果表明,发震断层走向约47.810°±2.218°,倾角约36.664°±2.499°;震中位置为87.715°E、34.365°N,震源深度为5.673 km。同震滑动分布主要集中在3.9~7.5 km深度,最大滑动量约0.42 m,平均滑动角约-66.598°±3.258°。本次地震以正断为主,兼具少量左旋走滑性质,反演得到的矩震级为M_(W)5.5,略小于USGS提供的震级。Based on Sentinel-1A data,we use differential synthetic aperture radar interferometry(DInSAR)technology to obtain the LOS coseismic deformation field.We retrieve the geometric parameters of the seismogenic fault and fault slip distribution using Bayesian methods(BM)based on sequential Monte Carlo(SMC)sampling.The results show that the strike of seismogenic fault is about 47.810°±2.218°,the dip angle is about 36.664°±2.499°.The epicenter location is 87.715°E,34.365°N,and the corresponding depth is 5.673 km.The coseismic slip distribution is concentrated at a depth of 3.9~7.5 km,and the maximum slip is 0.42 m.The average rake angle is-66.598°±3.258°,which indicates that this earthquake is dominated by normal fault with slightly left-lateral strike-slip.The inverted moment magnitude isMW5.5,slightly less than the magnitude published by the USGS.

关 键 词：双湖地震 同震形变场 断层滑动分布 

分 类 号：P315[天文地球—地震学]