FUNDAMENTAL STUDY ON PULSE-TYPE EARTHQUAKE MOTION NEAR SEISMIC FAULT BASED ON DYNAMIC RUPTURE MODEL

Abstract

This study investigates fundamental properties of the pulse-type earthquake motions adjacent to a vertical strike-slip fault using the dynamic rupture model based on the slip-weakening law. Surface-rupturing leads to large final slip in the surface region which has less influence on amplification of velocity pulse in fault-normal direction. It is inferred from parameter study that large stress drop and small critical slip result in large velocity amplitudes as consequences of the faster rupture velocity and increase of slip rate. Peculiar spatial variation of pulse velocity is also discussed in related with a supershear rupture.