Quantification of Fluid Migration Via faults Requires two-way Coupled Hydromechanical Simulations

Subsurface storage of fluids triggers pressure and volume changes in reservoirs, caprocks and faults. In this context, hydraulic fault conductivity can increase by several orders of magnitude, promoting upward migration of reservoir fluids into shallow freshwater aquifers. In the present study, we compared one-way and two-way hydromechanical couplings to quantify the impacts of subsurface fluid storage on fluid migration via a fault. Our simulation results emphasize the requirement of two-way coupled hydromechanical simulations, since neglecting petrophysical changes in the one-way coupling leads to an underestimation of fault pressure gradients, and thus fluid migration.