Co2 Plume Migration in Tilted Aquifers Subject to Groundwater Flow

Carbon dioxide injection into geological formations such as deep saline aquifers for storage is an efficient technology to mitigate atmospheric CO2 emissions. Understanding the subsurface migration of the CO2 plume is important for storage capacity estimation, and for leakage risks assessments. In this study, we present a numerical simulation analysis of CO2 plume migration in tilted aquifer with groundwater flow and subjected to residual and dissolution trapping. We divide the post-injection migration of the plume into early and late post-injection periods. Here, we investigate the impact of aquifer slope with groundwater flow on the evolution of the plume during its early post-injection migration. Our analysis provides estimates of the height, extent and velocity of injected plume to understand how fast and far it migrates, and the amount of CO2 that remains mobile. The results show that as aquifer slope increases, the CO2 plume on the up-dip side migrates faster upwards; however, its height decreases with time. This implies that a smaller volume of CO2 remains mobile in the system for larger dip angles, thus reducing the potential for CO2 to escape to the surface. Our calculation of the instantaneous velocity demonstrates that the plume migration decelerates with time.