Reflection, transmission and AVO response of inhomogeneous plane waves in thermoporoelastic media with two-temperature equations of heat conduction

Abstract

We develop a modified fluid-saturated thermoporoelastic model by introducing two temperature equations to account for the temperature differences between the solid skeleton and the pore filling. The modified two-temperature-generalized thermoporoelastic (TTG) equation is an extension of the classical single-temperature (ST) Lord-Shulman (LS), Green-Lindsay (GL) and generalized LS theories. It predicts four compressional waves and one shear wave based on the analysis of inhomogeneous plane waves. We study the exact reflection and transmission coefficients (R/T) at the interface separating two thermoporoelastic half-spaces and develop an amplitude-variation-with-offset (AVO) approximation. Comparison with the Biot poroelastic case of the water/oil contact shows that the TTG model reproduces the exact R/T results. The AVO response of oil, gas, and real CO2 geosequestration reservoirs illustrates the practical applicability of the proposed model and provides the theoretical basis for the exploration of high-temperature resources.