Simulation of the cumulative impacts of CO2 geological storage and petroleum production on aquifer pressures in the offshore Gippsland Basin

Generally, the CO2 injectivity for a pressure-depleted aquifer is likely to be higher than that for a hydrostatically-pressured aquifer, and the difference should be related to the volumes of previous petroleum and associated water production. CO2 injection and petroleum production operating independently can result in significant over- or underpressuring in a basin, potentially causing land uplift/subsidence or contamination of groundwater. The simulation results in this study suggest that, given the right injection concept, unwanted pressure changes and associated impacts could be significantly reduced when CO2 injection and petroleum production operated conjunctively.