A fourth-order accurate finite-difference program for the simulation of SH-wave propagation in heterogeneous viscoelastic medium

This article presents a staggered grid time-domain finite-difference (FD) program for the simulation of SH-wave propagation in a viscoelastic heterogeneous medium. The incorporation of realistic damping in FD program is based on a rheological model widely known as generalized Maxwell body (GMB-EK). The accuracy of implementation of realistic damping is validated by comparing the numerically computed frequency dependent quality factors and phase velocity with the same computed using GMB-EK rheological model and the Futterman's relationship. The accuracy was also validated by comparing the numerically computed soil amplification at resonance frequency for different damping with the analytical solutions. The stability and grid dispersion are also studied in details.