Coseismic Deformation and Fault Inversion of the 2017 Jiuzhaigou Ms 7.0 Earthquake: Constraints from Steerable Pyramid and InSAR Observations

The 8 August 2017 Ms 7.0 Jiuzhaigou earthquake was generated in the transition zone between Tazang fault, Huya and Minjiang all being part of East Kunlun fault system. In this study, two pairs SAR (synthetic aperture radar) data from Sentinel-1 satellite were used to derive surface displacement observations along line-of-sight (LOS) directions using differential interferometric (D-InSAR) method. A steerable pyramid filtering method (i.e., a for linear multiscale, multidirectional decomposition technology) proposed optimize enhance geological features image coseismic deformation field. 3D derived under constraint combined D-InSAR MAI small baseline subset InSAR (SBAS-InSAR) time series obtain cumulative across Fault slip inversion results interferogram indicate that dominated by left-lateral slip, movement horizontal deformation, vertical small, variable east–west direction largest, with maximum 0.2 m east 0.14 west. is about 77 cm, which located at depth 9 km. moment magnitude obtained Mw 6.6, seismic fault.