Thousand Seismic Sites for a Sight of Crustal Activity

Abstract

Weakening process of the crust is an important key for understanding of crustal dynamics. Earthquake faulting is a phenomenon of inelastic deformation taking place within seismogenic zone and its occurrence is affected by stress condition of the crust. High-resolution hypocenter distribution, fault orientation of small earthquakes, and structure of seismic wave propagating velocity illuminate present condition in the crust. Therefore, we are carrying out seismic observation by one thousand stations in an aftershock area of the 2000 Western Tottori earthquake (M7.3). It is expected that the detectability of earthquake is smaller than magnitude of minus 1 and accuracy of the fault orientation is less than several degrees. These observation enable us to visible the crustal activity.