Prediction of Crustal Dynamics for the Yishu Fault Zone Based on Slip Susceptibility Analysis

Abstract. We estimate the slip susceptibility of faults in the Yishu fault zone using a slip tendency analysis based on coupled tectonic stress profiles. Studying in situ stress data and focal mechanism solution data collected in this area over more than 30 years, we construct the stress profiles of the study area using the coupling analysis method for deep and shallow stress data. Subsequently, the slip susceptibility of the faults is comprehensively evaluated based on various stress indicators and other related influencing factors. Our results show that μ_m is low in the deep and shallow crust of the Yishu fault zone, indicating a relatively low degree of overall stress accumulation. A comprehensive evaluation of the susceptibility of fault slips based on five typical influencing factors (μ_m, K, θ, S-wave velocity, and seismic density) indicates that the overall seismic risk in the central part of the Yishu fault zone is not high, while the northwestern Yishu fault zone exhibits high seismic risk. The southeastern part of the Yishu fault zone reflects the transition from medium to low seismic risk. These results provide geomechanical and fault mechanics evidence for evaluating the regional crustal dynamics of the Yishu fault zone.