Co-seismic Deformation and Source Model of the 2017 Mw6.3 Earthquake in Jinghe, Northwest China Constrained by InSAR and GNSS Measurements

Abstract:

At 8th August 2017, a Mw6.3 earthquake attracts the Xinjiang, northwest China. The epicenter is located at the border region of the North Tien Shan and Junggar basin. This earthquake is tthe first event that received adequate seismic and geodetic observations at this border region. It provides a rare chance to gain our insights into the interaction between the Junggar Basin and the north Tien Shan. In this study, near field co-seismic deformation caused by the 2017 Jinghe earthquake is measured with InSAR and GNSS technique. The quasi-eastward and quasi-upward co-seismic deformation are obtained with the ascending and descending Sentinel-1A observation. The source model paraments of this event were invert with the geodetic data and the nonlinear multipeak particle swarm optimization (MPSO) algorithm. Our result suggests that this event happened at a blind-thrust fault plane with the strike of 86.8 and the dip of 40.1. Predominant slips occur at the center of the fault plane with depths from 11.5 km to 18.5 km. The maximum slip is 0.49 m. The estimated total geodetic moment released with fault slips is about 2.95 . It is equivalent to a moment magnitude about Mw 6.28.