Seismicity Simulation in Western Sichuan of China Based on the Fault Interactions and Its Implication on the Estimation of the Regional Earthquake Risk

Abstract

AbstractSeismicity over 10,000 years in Western Sichuan of China has been simulated based on the mechanical synthetic seismicity model we developed. According to the analysis of the simulated synthetic seismic catalogue, the occurrence of strong earthquakes with Ms ≥ 7.0 in the whole region of Western Sichuan is rather random, very close to the Poisson process with seismic rate 0.0454/a, which means it is reasonable to estimate the regional earthquake risk with Poisson model in Western Sichuan. However, the occurrence of strong earthquakes with Ms ≥ 7.0 on the individual faults of Western Sichuan is far from Poisson process and could be predicted with a time‐dependent prediction model. The fault interaction matrices and earthquake transfer possibility matrices among the faults in Western Sichuan have been calculated based on the analysis of the simulated synthetic catalogues. We have also calculated the static change in Coulomb failure stress (CFS) on one fault induced by a strong earthquake on another fault in Western Sichuan to discuss the physical implications of the earthquake transfer possibility matrices inferred from the synthetic catalogue.