基于D—InSAR的九寨沟地震同震形变场反演分析  

Inversion analysis of co-seismic deformation field of Jiuzhaigou earthquake based on D—InSAR

作　　者：赵强[1] 杨国东[1] 张旭晴[1] 邵鹏 ZHAO Qiang;YANG Guo-dong;ZHANG Xu-qing;SHAG Feng(College of Geo-exploration Science and Technology,Jilin University,Changchun 130026,China;China Petroleum Pipeline Engineering Ltd,Langfang 065000,Hebei,China)

机构地区：[1]吉林大学地球探测科学与技术学院,长春130026 [2]中国石油管道局工程有限公司,河北廊坊065000

出　　处：《世界地质》2018年第3期938-944,共7页World Geology

基　　金：国家自然科学基金(41472243)资助

摘　　要：利用覆盖九寨沟地区的RadarSat—2数据与Sentinel—1A数据,采用精轨数据进行定轨,消除轨道误差,并结合合成孔径差分(D-InSAR)方法中的双轨差分技术,获取2017年8月8日Mw7. 0级地震的同震形变场。结果表明,视线方向(LOS)最大沉降量约为20 cm,隆起量达9 cm。基于弹性半空间形变模型反演该地震的断层滑动分布,得出该地震断层滑动以左旋走滑为主,走向为330°,倾角为32°,滑动角为-170°,同震滑动分布主要集中在4～12 km深度处,最大滑动量位于9 km处,约为6. 14 m,平均滑动量为0. 57 m。反演获得的地震标量矩为4. 06E+18N·m,震级Mw约为6. 4,深度为19. 5 km。On the basis of RadarSat-2 data and Sentinel-1A data covering the Jiuzhaigou area,the August 8,2017 co-seismic deformation field of the Mw 7. 0 Earthquake is acquired by determining orbit using precision orbit data,eliminating orbital errors and combining the Dual-track difference technique in the synthetic aperture difference( D-InSAR) method. The results show that the maximum subside of the line of sight( LOS) is about 20 cm and the amount of upraise is 9 cm. Based on the elastic half-space deformation model,the fault slip distribution of the earthquake was inverted and the slip of the fault was dominated by left-lateral strike-slip,with a strike of 330°,an inclination of 32°,a sliding angle of -170°. The co-seismic slip distribution focused on the depth of 4 ~ 12 km,with the maximum sliding amount of 6. 14 m located at the depth of 9 km,and the average sliding amount of 0. 57 m. The seismic scalar moment obtained by inversion is 4. 06 E + 18 N·m,the magnitude Mw is about 6. 4,and the depth is 19. 5 km.

关 键 词：九寨沟地震 D-InSAR同震形变场 滑动分布反演 震源机制 

分 类 号：P631.44[天文地球—地质矿产勘探]