Numerical experiments to characterize P-wave attenuation in partially saturated non-isothermal porous media

We use a model that combines the Biot and Lord- Shulman (LS) theories to study mesoscopic P-wave attenuation in partially saturated thermo-poroelastic media. This effects are due to the presence of mesoscopic-scale heterogeneities causing mode conversion from fast P-waves to slow Biot and thermal waves. A typical mesoscopic heterogeneity has a size of tens of centimeters and can be due to local variations in lithological properties or to patches of immiscible fluids. The equations were solved in a 1D layered media using the Finite Element method with the seismic response being recorded in order to observe and quantify attenuation effects. For this purpose, the spectral ratio and frequency shift methods were used to estimate the quality factor Q. In the numerical examples thermal effects are considered (coupled Case) or omitted (uncoupled Case). The results show that the inclusion of thermal effects constitutes a mesoscopic loss mechanism.