Slip properties of serpentine under high fluid pressure and implication for slow earthquake

2014 Fiscal Year Final Research Report

• Project/Area Number: 24340105
• Research Category: Grant-in-Aid for Scientific Research (B)
• Allocation Type: Partial Multi-year Fund
• Section: 一般
• Research Field: Solid earth and planetary physics
• Research Institution: Hiroshima University
• Principal Investigator: KATAYAMA Ikuo 広島大学, 理学(系)研究科(研究院), 教授 (10448235)
• Project Period (FY): 2012-04-01 – 2015-03-31
• Keywords: 蛇紋岩 / スロー地震 / 沈み込み帯

Outline of Final Research Achievements

Slow earthquakes occurred at subduction zone are distinct from regular earthquake in terms of their slip behaviors (e.g., Ide et al. 2007). We consider this difference to relate to localized hydration reactions at the plate interface that influence the frictional properties. The results of laboratory friction experiments indicate that, under high fluid pressure, simulated serpentine faults tend to be unstable at elevated temperature close to dehydration, which are characterized by a significantly slow rate of stress drop during instability. These properties are consistent with the characteristics of subduction-related slow earthquakes, which exhibit a relatively long duration for energy release.

Free Research Field

岩石変形学