Inferring frictional properties at wide range of slip rate based on natural earthquake data and physical modelling

2017 Fiscal Year Final Research Report

• Project/Area Number: 25800253
• Research Category: Grant-in-Aid for Young Scientists (B)
• Allocation Type: Multi-year Fund
• Research Field: Solid earth and planetary physics
• Research Institution: The University of Tokyo (2014-2017); National Institute of Advanced Industrial Science and Technology (2013)
• Principal Investigator: Ando Ryosuke 東京大学, 大学院理学系研究科(理学部), 准教授 (10455256)
• Project Period (FY): 2013-04-01 – 2018-03-31
• Keywords: 地震 / スロー地震 / 摩擦 / 破壊 / 東北地方太平洋沖地震 / 断層 / 沈み込み帯 / シミュレーション

Outline of Final Research Achievements

We investigated a wide range of the slip rate dependences of the frictional strength on the natural fault surface by targeting the after-slip area found associated with the foreshock of the 2011 Tohoku-oki earthquake. We numerically compute the shear stress change by using the boundary integral equation method with the inputs of the kinematically obtained slip profiles. As the result, the after-slip exhibits the frictional properties of the weak rate-strengthening at the low rate of 10**-6 [m/s] and of the strong rate-weakening at the high rate of 1 [m/s].

Free Research Field

地震学