Earthquake modeling in the Dead Sea Basin

Abstract

We simulate 75 seconds of 1.5 Hz wave-propagation of the 1927 Jericho earthquake (ML 6.2) using a staggered-grid finite-difference (FD) method. From the time histories we compute peak ground velocities and pseudo-acceleration responses at 1 Hz in a 3D model including the Dead Sea Basin substructure. We compare the accelerations to values computed (a) for a homogeneous model and (b) using an attenuation relation similar to the one integrated in the building code 413 of Israel. With accelerations at 1 Hz, we show that the Dead Sea Basin substructure is responsible for a significant radiation anisotropy in ground motion attenuation when the source is located within the basin. Rupture dynamics effects of strike-slip events along faults bounding the basin enhance this behaviour. We show that both, the homogeneous model and the attenuation relation, underestimate the spectral responses on average by factors between 1.5 and 5.