| Budget Amount *help |
¥17,810,000 (Direct Cost: ¥13,700,000、Indirect Cost: ¥4,110,000)
Fiscal Year 2015: ¥3,640,000 (Direct Cost: ¥2,800,000、Indirect Cost: ¥840,000)
Fiscal Year 2014: ¥3,640,000 (Direct Cost: ¥2,800,000、Indirect Cost: ¥840,000)
Fiscal Year 2013: ¥10,530,000 (Direct Cost: ¥8,100,000、Indirect Cost: ¥2,430,000)
|
|---|
| Outline of Final Research Achievements |
Slow earthquakes in subduction zones have been considered as the key phenomenon associated with megathrust earthquakes. Several mechanisms have been proposed, but the cause of slow earthquakes remains elusive. One possibility is that an increase in pressure of pore fluid promote slow slip in subduction faults, yet role of fluid pressure in mechanics of slow earthquakes is poorly understood. Therefore, we conducted friction experiments on blueschist fault rocks to investigate the influence of effective stress on frictional behavior. Our results show a transition from stable to unstable behavior with decreasing effective normal stress, which is mechanically equivalent to increasing fluid pressure. This transition is a prerequisite for generating slow earthquakes. Our results imply that high pore pressures are a key factor for nucleating slip leading to slow earthquakes.
|
