Rupture initiation and stop under nonuniform stress and friction

2023 Fiscal Year Final Research Report

• Project/Area Number: 20K14583
• Research Category: Grant-in-Aid for Early-Career Scientists
• Allocation Type: Multi-year Fund
• Review Section: Basic Section 17040:Solid earth sciences-related
• Research Institution: National Institute of Advanced Industrial Science and Technology (2021-2023); National Research Institute for Earth Science and Disaster Prevention (2020)
• Principal Investigator: Urata Yumi 国立研究開発法人産業技術総合研究所, 地質調査総合センター, 主任研究員 (80780452)
• Project Period (FY): 2020-04-01 – 2024-03-31
• Keywords: 断層 / 破壊開始 / 地震規模 / 非一様応力摩擦場

Outline of Final Research Achievements

Theoretical works on rupture initiation have assumed the uniform or axisymmetric shear stress distribution and the uniform friction properties. However, stress and friction distributions are considered to be heterogeneous, and the heterogeneity would contribute to the stopping of ruptures. In this study, we showed that indices for the prediction of rupture initiation and the earthquake magnitude, based on the static fracture mechanics. We applied the indices to anticipated Nankai-trough earthquakes. These results would be useful in the study on the earthquake rupture scenarios.

Free Research Field

地震学

Academic Significance and Societal Importance of the Research Achievements

本課題では、空間非一様な応力・摩擦下での断層破壊の開始と地震規模の予測に関する指標を得ることができた。これは、破壊の開始・停止の物理に関する基礎的な理解を深化させるものである。また、この指標は、今後、防災減災対策にも有用な、想定地震の震源位置や規模の予測に関する研究を進める上での基礎となりうる。