[S-GD01] Geodetic Advances in Crustal Dynamics and Environmental Change for Taiwan and Neighboring Regions

[SGD01-09] Dynamic rupture process of active fault zones in eastern Taiwan with numerical simulation

*XiaoFei GUO^1,2, Yosuke Aoki², Jianghai Li¹ (1.School of Earth and Planetary Sciences, Peking University, 2.Earthquake Research Institute, The University of Tokyo)

Keywords:fault rupture, discrete element method, longitudinal valley fault zone

Active fault zones have complex structural and geometric features, and the complexity of fault rupture increases the difficulty of quantifying seismic hazard. Understanding the interplay between fault zones and earthquakes is a challenge for simulating the dynamic fault rupture process and is important for seismic hazard and risk assessment. Previous numerical modelling experiments have not yet discussed much the relationship between ruptures around complex active faults and earthquake occurrence. In this study, an attempt has been made to model and analyze the rupture process of earthquake faults using discrete element methods to elucidate the geological evolution of active faults and the occurrence of earthquakes by processing a dynamic model for interpreting the complexity of the rupture. To determine its feasibility, we regard the longitudinal valley fault zone in eastern Taiwan as the study area, and the simulation analyses are mainly carried out on the rupture of reverse-strike faults and strike-slip faults. By comparing actual observational data such as InSAR with surface fault deformation, the feasibility of the model can be determined. Deep fault ruptures can reveal potential rupture development patterns of the fault under multiple earthquake events in the study area. Additionally, displacement magnitude and internal stress distribution can be obtained, providing insights for future seismic hazard assessments.