联合InSAR和高频GNSS位移波形反演2022年青海门源M6.9地震同震破裂过程

Using differential interferometric synthetic aperture radar (InSAR) and pixel offset tracking, we obtained both the coseismic displacements along line-of-sight and near-field range offsets of the 2022 Qinghai Menyuan M6. 9 earthquake from Sentinel-1 SAR images, and also got high-rate displacement waveforms at 16 Global Navigation Satellite System stations through epochwise precise point positioning solutions. Based on these measurements, we then jointly inverted the rupture process of the 2022 Menyuan M6. 9 earthquake. Our results show that this earthquake was a bilateral asymmetric event, which ruptured two faults at strikes of 82 degrees and 112 degrees with a total length of similar to 26 km. Most of the slip occurred between 0 and 5 km, and the peak slip was similar to 4 m. A total seismic moment of 8. 65 x10(18) Nm (equivalent to M(w)6. 56) was released within similar to 10 s. Coulomb failure stress change analysis indicates that stress levels of two neighbouring seismogenic faults at 10 km were increased, which was responsible for the subsequent aftershocks in this region. Our slip model implies insignificant shallow slip deficits, considering InSAR time series from 2014 to 2021, so we speculated that there should be negligible shallow creeping along Lenglongling and Tuolaishan segments during the long-term interseismic period.