Seismic Waves in Heterogeneous Crust-Mantle Layers under Initial Stresses

Abstract

This article investigates the propagations of SH-waves and Rayleigh-type waves in a pre-stressed heterogeneous half-space and also Love-type waves in a pre-stressed heterogeneous layer overlying a pre-stressed heterogeneous half-space. Wave-velocity relations for SH-waves, Rayleigh-type waves, and dispersion equation for Love-type waves are derived. The results reflect that initial stress and inhomogeneity decrease the phase velocity of the SH-waves and Rayleigh-type waves. The phase and damping velocities of Love-type waves decrease with wave number, initial stress of the upper media, and inhomogeneity of the lower media, whereas they increase with initial stress of the lower media and inhomogeneity of the upper media.