[S-CG49] Integrative seismic and secondary hazard/risk assessment

[SCG49-07] Building a Community Fault Model: Insights from Dynamic Rupture Simulations of Natural Earthquakes

★Invited Papers

*Ryosuke Ando¹ (1.Graduate School of Science, University of Tokyo)

Keywords:3D fault geometry, Earthquake source processes, Stress field, Dynamic rupture simulations

The importance of fault geometry has been emphasized based on surface fault traces, leading to the forecast of the earthquake sizes and segmentations of fault systems. However, the information on the fault geometry is not utilized in forecasting the dynamic rupture processes and characterizing non-uniform distributions of fault slips. Recent developments of high-resolution observations in space and time unveil the complex non-planar geometry of faults. Further, by incorporating the 3-dimensional non-planar geometry, fully dynamic rupture simulations successfully reproduce the observed characteristics of rupture processes and sip heterogeneity of large natural earthquakes. Examples include recent events such as the 2016 Kaikoura, New Zealand Earthquake, the 2023 Kahramanmaras Earthquake and the 2024 Noto-peninsula Earthquake. We can constrain the initial stress condition by referring to the preseismic estimates of the regional stresses using stress tensor inversion techniques. Therefore, we can conduct forward modeling for individual faults to assess future earthquake rupture scenarios. In this talk, I will discuss the importance of the 3-D non-planar fault geometry models and introduce the Japanese Community Fault Model project, which aims to build the non-planar representation of the major faults in the entire Japan scale.