Stress evaluation of earthquake fault and slow slip fault in subduction zone

2021 Fiscal Year Final Research Report

• Project/Area Number: 19K04019
• Research Category: Grant-in-Aid for Scientific Research (C)
• Allocation Type: Multi-year Fund
• Section: 一般
• Review Section: Basic Section 17040:Solid earth sciences-related
• Research Institution: Yamaguchi University
• Principal Investigator: Sakaguchi Arito 山口大学, 大学院創成科学研究科, 教授 (80304666)
• Project Period (FY): 2019-04-01 – 2022-03-31
• Keywords: 断層 / 歪み / 応力 / カルサイト

Outline of Final Research Achievements

It had been difficult to distinguish whether the fault caused a seismic rapid slip or a slow slip from the fault rock. We proposed that the slip mode can be identified from the stress concentration condition around the fault. For this subject, we improved the technique of the calcite twin analysis. It was found that strain distribution around the fault depends on the depth.
In the process of this study, we developed new technique to estimate stress/strain condition of rock and related materials. This method can apply to safety evaluation for concrete buildings.

Free Research Field

構造地質学

Academic Significance and Societal Importance of the Research Achievements

地震発生帯が巨大地震やスロー地震といった複雑な挙動を起こすメカニズムを説明するうえで，研究対象となる陸上断層の過去の挙動を知る手段の開発は急務であった．本研究は新しい応力・歪み計を開発して，これに有効であることを示した．
また，同手法はコンクリート構造物にも応用できるため，経年劣化や災害によるダメージを受けた構造物の安全評価にも利用出来る（特許出願済み）．