Wave propagation in poroelastic media: A velocity‐stress staggered‐grid finite‐difference method with perfectly matched layers

Abstract

We present a velocity-stress staggered-grid finitedifference method to simulate wave propagation in heterogeneous poroelastic media. Biot’s theory expressed in terms of velocity and stress is to obtain a set of first order hyperbolic equations. This formulation is discretized into a staggered grid both in space and time domain with the harmonic average of the material properties to account for heterogeneous media. To simulate the wave propagation in an unbounded media, the perfectly matched layer method is used as an absorbing boundary condition. Numerical simulations of Biot’s theory show the existence of a slow P wave in porous media and are also qualitatively consistent with previous analytic predictions of the wave propagation in fluid saturated poroelastic media.