利用InSAR技术研究2018年西藏谢通门MW5.6地震发震构造

Seismogenic Structure of 2018 Xietongmen, Tibet MW5.6Earthquake Inferred from InSAR Data

摘要:

2018年12月24日在西藏日喀则市谢通门县发生M_W5.6地震。利用Sentinel-1A卫星数据和D-InSAR技术，获得该地震LOS方向的同震形变场图像，并以此为约束反演地震断层的几何参数和同震滑动分布特征。反演结果表明，谢通门M_W5.6地震发震断层近南北走向，断面倾向西，倾角约35°，破裂长度约12 km，同震滑动主要集中在4~11 km深度范围内，以正断倾滑为主，最大滑动量0.18 m，矩震级M_W5.6。2018年谢通门地震发震构造是谢通门—申扎伸展断裂系中的一条新生盲断层。

Abstract:

On December 24, 2018, a M_W5.6 earthquake occurred in Xietongmen County, Shigatse City, Tibet. This study utilizes Sentinel-1A satellite SAR data and D-InSAR technology to obtain an image of the co-seismic deformation field in the LOS direction and then inverses the geometric parameters and co-seismic slip distribution of the seismological fault of the event. The results show that the fault associated with the M_W5.6 earthquake lies in a near NS-direction, has a dip angle of 35°, and a rupture length of 12 km. The co-seismic slip is mainly concentrated in a range of 4-11 km, the maximum slip is 0.18 m, and the moment magnitude is M_W5.6. In addition, it is determined that the seismogenic fault of the Xietongmen earthquake in 2018 is a new blind fault belonging to the Xietongmen—Shenzha extensional fault system.