基于升降轨Sentinel-1 SAR影像研究精河MS6.6地震震源机制

采用Sentinel-1A/B卫星升降轨SAR数据获取了2017-08-09新疆精河MS6.6地震的同震形变场，并以InSAR形变场为约束，利用均匀滑动模型和分布式滑动模型反演了发震断层的滑动分布。结果表明，升降轨InSAR形变场均显示为隆升，形变影响范围约30 km × 40 km；发震断层走向约为83.8°，倾角约为40.6°，滑动角约为89.1°，震源深度约为20.7 km，矩震级为MW6.35，同震位错以逆冲运动为主兼有极少量左旋走滑分量。精河地震的发震断层为库松木楔克山前断裂，该次地震是新疆北天山地区逆冲断裂带深部发生错动的结果。

The 2017 Jinghe MS6.6 Earthquake Inversion from Ascending and Descending Sentinel-1 Observations

On 9th August, 2017, an MS6.6 earthquake occurred in Jinghe county of Xinjiang, China. In this study, ascending and descending tracks of Sentinel-1A/B images are employed to derive the precise coseismic surface displacements, then a two-step inversion strategy with uniform slip model and distributed slip model is used to estimate the fault geometry and coseismic slip distribution. InSAR results show that the coseismic deformation range is about 30 km×40 km. Our model suggests that the distributed slip mode can fit the observations very well. The earthquake fault is a thrust fault with a strike of 83.8°, a dip of 40.6°, a rake of 89.1°, a focal depth of 20.7 km, and the moment magnitude is 6.3, which is consistent with seismological results. The causative fault of Jinghe earthquake is Kusongmuxieke mountain front fault, and this earthquake is caused by the dislocation at the deep of thrust fault zone in the northern Tianshan mountains, Xinjiang.