Analysis of the dynamics of strike slip faulting

Abstract

Strike slip generated by wave motions and wave motions generated by strike slip are analyzed for vertical surface faults on which motion is opposed by a frictional shear stress, which is assumed to increase linearly with depth. The fault is a plane of discontinuity in a homogeneous, isotropic, linearly elastic half-space. The half-space is subjected to normal stresses that increase linearly with depth and to spatially uniform antiplane shear stresses. The horizontally polarized shear motions occurring in these two problems can be treated by a single mathematical analysis, which is presented in some detail. The results of this paper include an expression for the rate of advance of the leading edge of the zone of sliding in the initial stages of the sliding process and an expression for the maximum depth of penetration of the zone of sliding. Shear stresses in the fault plane have also been computed, and an upper bound has been established for the relative displacement at the surface trace of the fault.