Coupled Thermo-hydro-Mechanical Effects on Caprock Stability During Carbon Dioxide Injection

This study presents a numerical investigation of the effects of coupled material properties on the caprock stability. A thermo-hydro-mechanical framework is proposed in order to reproduce the physical processes. The results indicate that for a given geometrical configuration and a given temperature difference between injected CO2 and reservoir, the potential for the caprock failure may increase or decrease. This contradictory behaviour mainly depends on the combination of the thermal-hydro-mechanical parameters, i.e., thermal expansion coefficient, stiffness and the Biot coefficient. Therefore, the coupled effects of material properties on the caprock stability should be addressed in a combined way for low-temperature CO2 injection problems.