利用InSAR数据约束反演2017年Mw6.3精河地震同震破裂模型

利用Sentinel-1降轨卫星数据，研究2017-08-09新疆精河M_W6.3地震的同震形变与断层滑动破裂。考虑轨道和大气误差的影响，基于模型改正后的精细同震干涉图显示，视线向最大地表位移约为7 cm，未发现有地表破裂。此外，基于弹性半空间位错模型，采用两步法策略分别反演地震的均匀断层几何参数和同震滑动分布，结果显示，精河地震发震断层以逆冲运动为主，主破裂区位于8~17 km深度，最大滑移量为0.6 m，表明该地震是一次由逆冲型隐伏断层产生的单次破裂事件。InSAR结果给出的地震释放矩能量为2.91×10¹⁸ Nm，相当于矩震级M_W6.25，与USGS、CENC等机构给出的震级一致。

Constraints on Coseismic Rupture Model of the 2017 MW6.3 JingheEarthquake from InSAR Data

In this study, InSAR data from Sentinel-1 satellite are used to image the coseismic deformation and constrain the focal mechanism of the M_W6.3 earthquake that struck Jinghe county, in the central segment of the Tien Shan Orogenic system, northwestern China, on 9th August 2017. After the orbit and atmospheric error are corrected in the coseismic interferogram, we find a maximum surface displacement in line of sight (LOS) up to 7 cm, and no surface rupture in this event. Assuming an elastic homogeneous half-space, a two-step inversion strategy is adopted to inverse the fault geometry and slip distribution, respectively. Our results demonstrate this event is dominated by thrust-slip with no strike-slip, and the main slip zone is in depths of 8 to 17 km with a maximum slip of 0.6 m, suggesting this event is a blind reverse thrust rupture with one asperity. The seismic moment determined in this study is 2.91×10¹⁸ Nm, corresponding to M_W6.25, which is consistent with the focal mechanism from USGS and CENC.