日本地球惑星科学連合2019年大会

講演情報

[E] ポスター発表

セッション記号 S (固体地球科学) » S-CG 固体地球科学複合領域・一般

[S-CG48] Science of slow earthquakes: Toward unified understandings of whole earthquake process

2019年5月29日(水) 17:15 〜 18:30 ポスター会場 (幕張メッセ国際展示場 8ホール)

コンビーナ:井出 哲(東京大学大学院理学系研究科地球惑星科学専攻)、廣瀬 仁(神戸大学都市安全研究センター)、氏家 恒太郎(筑波大学生命環境系)、波多野 恭弘(東京大学地震研究所)

[SCG48-P24] A new hydrothermal, low to high speed rotary-shearing apparatus: Reproduction of slow/megathrust earthquakes in laboratory

*廣瀬 丈洋1谷川 亘1濱田 洋平1岡崎 啓史1 (1.国立研究開発法人海洋研究開発機構 高知コア研究所)

キーワード:friction、hydrothermal、slow to fast slip

Earthquakes involve a wide range of slip rates, from slow/aseismic to fast/seismic slip along faults. Thus, frictional properties of faults over wide slip rates (nm/s to m/s), in particular under hydrothermal conditions similar to those expected in seismogenic zones are essential for a unified understanding of all earthquake events. A new hydrothermal, low to high speed rotary-shearing apparatus has been installed at Kochi/JAMSTEC, in order to study the fault constitutive properties at slow to fast slip rates and the physicochemical mechanisms underlying mechanical responses. The apparatus is currently capable of applying slip rates from 100 nm/s to 2 m/s, normal stress up to 55 MPa, fluid pressure up to 120 MPa and temperature up to 450oC with infinite displacement. We have been improving the apparatus to work as we intended. In pilot tests, we used metamorphic rocks (pelitic and green schists) as starting materials that are potentially distributed at and below seismogenic zones along hot and young subduction zones. We will present our preliminary results with the basic design of the apparatus.