Abstract:
A
MS6.9 earthquake occurred at Menyuan County, Haibei Prefecture, Qinghai Province on 8 January 2022. Relocation results of the Menyuan
MS6.9 earthquake sequence suggest that there is still a possibility for another strong earthquake in Menyuan area. Based on topography data and three-dimensional velocity structure in the source zone, together with the preliminary result about the source rupture process of Menyuan earthquake, we simulated seismic wave propagation of Menyuan
MS6.9 earthquake by curvilinear-grid finite difference method, and obtained seismic intensity distribution accordingly. The simulated results show that the ground motion attenuation along the direction of fault strike is significantly smaller than that along the direction of fault dip. The maximum seismic intensity caused by Menyuan
MS6.9 earthquake is about Ⅷ degree, and located in the vicinity of the rupture initial point. Theoretical intensity distribution is roughly consistent with the seismic intensity distribution from field surveys. Affected by the directional effects of strong ground motion and undulated topography, earthquake disasters mainly concentrated in the WNW and ESE directions of the seismic fault.