Synthetic aperture radar interferometry–based coseismic deformation and slip distribution of the 2022 Menyuan MS6.9 earthquake in Qinghai, China

Abstract

On January 8, 2022, a 6.9 magnitude earthquake occurred in Menyuan County, Qinghai Province, with the epicenter located at the intersection of the Tuolaishan Fault and the Lenglongling Fault, which are part of the Qilian–Haiyuan fault zone. This study investigated the sliding characteristics and seismic mechanism of the earthquake to understand the activity and seismic risk of the fault on the northeastern margin of the Qinghai–Tibet Plateau. This paper analyzed Sentinel-1 synthetic aperture radar images to obtain the coseismic deformation field of the earthquake, which was then used to invert the slip distribution of the seismogenic fault and the coseismic Coulomb stress on the surrounding faults caused by the earthquake. It was found that the earthquake was primarily characterized by sinistral strike-slip movement. Along the satellite line of sight, the south wall of the fault had a maximum deformation of 0.62 m, and the north wall had a maximum deformation of 0.48 m. The coseismic slip distribution results indicated that the maximum slip of the earthquake was 4.51 m, and the moment magnitude was MW6.7. The Coulomb stress analysis showed that the 2016 Menyuan earthquake promoted the occurrence of the 2022 Menyuan earthquake.