Applications and future developments of the (thermo-) poro-elastic theory in geophysics

Abstract

Fluids are naturally present in the crust from subsoil to several kilometers deep. The representation of the Earth's crust as a purely elastic medium ignores the effects of fluids within rock pores. Because the presence of fluids alters the mechanical response of rocks, the theory of poro-elasticity can be used to more accurately represent the deformation and the stress field of the crust, especially when the fluid saturation of rocks is high. In a poro-elastic medium, fluids interact with the hosting rocks through the pore-pressure. If the fluids have significantly different temperatures compared to the surrounding rocks, the theory of poro-elasticity can be generalized to the thermo-poro-elasticity, which also takes into account the effects of the thermal expansion of the medium The geophysical applications of these theoretical frameworks are highly diverse and based on different modeling approaches and assumptions. In this work, we emphasize potential applications of thermo-poro-elasticity theory in developing increasingly complex models of rock-fluid interactions. To do that, we focus on the different modeling approaches employed in some recent models of deep fluid exploitation, reservoir induced seismicity, interaction between seismic faults and fluids, and hydrothermal systems in volcanic zones. Our review paper aims to offer a comprehensive summary of the models, theories, code packages, and applications pertinent to this area and suggest some possible future developments of thermo-(poro-elastic) models in different application areas.