Seismic Wave Velocity Structure beneath the Iwo-jima Volcanoes

Abstract

The seismic wave velocity structure in the Iwo-jima volcanoes area, having three layers of which velocities are as follows : first layer (upper) is 1 km/sec (Vp), second layer is 2.3 km/sec (Vp) and third layer is 4.0 km/sec (Vp). The Ohmori coefficient, k, for earthquakes in this island area is inferred to be 2.5 from the seismic prospecting.