3-D Finite-difference Simulation of Rayleigh-to-Love Wave Conversion

Abstract

Rayleigh-to-Love wave conversion by a Tien Shan-like mountain structure (MRS) is simulated using a 3-D finite-difference method. Love waves are generated through the oblique incidence of Rayleigh waves on the irregular front of the MRS at an azimuthal angle of 60  The wavefields of the vertical (W)  and radial (U) components show the propagation of transmitted and reflected Rayleigh waves along the great circle path and scattered P-SV waves leaking into the mantle, while the wavefield of the transverse (V) component clearly shows the generation process of converted Love waves. Spectral analysis of simulated waves in the MRS shows that the excitation of converted Love waves is dominant at periods near 20 s. At 20 s, the displacement and stress eigenfunctions of Rayleigh waves are similar to those of Love waves in the MRS model.  The characteristics of converted Love waves for an Alpine-like crustal structure reported by Snieder (1986) are also discussed.