Numerical modeling of poro-viscoelastic wave propagation in effective Biot media using a mixed grid finite difference frequency-space domain approach

To approximate seismic wave propagation in double porosity media, the effective Biot governing equations with complex frequency dispersion characteristics are numerically solved using an upscaled poro-visoelastic approach. We compute the wavefields for solid particle velocity and fluid flux in the frequency domain using a mixed grid finite difference method. A homogeneous full space model with a single Cole-Cole relaxation function representing the attenuation mechanism is used to show that the numerical solutions match well the analytical solutions for source centre frequencies of 102 Hz to 104 Hz. The computed pore pressure wavefield for a two-layer porous model is used to further validate our numerical method.