Dynamic rupture modeling and ground-motion simulations of the 2022 Mw 6.6 Luding earthquake

The 2022 Mw 6.6 Luding earthquake occurred on the Xianshuihe fault, one of China's most active faults. Revealing the rupture process of the Luding earthquake and exploring the distribution of high intensities is important for earthquake hazard reduction around the active Xianshuihe fault in the future. Therefore, we modeled the dynamic rupture and ground motions of the Luding earthquake. The dynamic rupture modeling demonstrates that the maximum slip of the fault plane is approximately 1.34 m, and the ground-motion simulations show the highest intensity attained is IX. In addition, we conducted a comparative analysis between synthetic data and station observation records, illustrating that our simulation results are compatible with the seismic station observations. We investigated the influence of geometric complexities on the Xianshuihe fault rupture and found that varying the dip angle of the southern segment may lead to premature rupture termination and constrain the rupture propagation. Our study provides insights into the complex geometry's effect on the physical process of large earthquakes on the Xianshuihe fault.