Regional CO sub(2) solubility trapping potential of a deep saline aquifer in Pohang basin, Korea

This paper presents regional CO sub(2) solubility trapping potential for stable CO sub(2) storage as immobile phase and decomposed form while CO sub(2) migrates through flow pathways characterized by the geological structure of an aquifer in Pohang basin, SE offshore Korea. The saline aquifer in Pohang basin has been selected as a target formation for geologic carbon storage due to favorable geologic structures and sedimentary strata defined through seismic survey. The aquifer is confined by southeast and northwest faults, and structure is unconfined and sloping toward the northeast direction. The main target within the aquifer to store CO sub(2) contains west plunging anticlines. In order to enlarge contact area of CO sub(2) with brine and improve injectivity, the CO sub(2) injector is located on marginal anticlines or small synclines. This structure may significantly affect CO sub(2) flow dynamics through upward migration pathways within the aquifer. We, in this area, provide estimates for CO sub(2) solubility trapping affected by dynamic CO sub(2) migration pathways and present different types of CO sub(2) trapping potentials. The numerical results based on thermodynamic equilibrium equation provide regional CO sub(2) solubility trapping potential which has a linear relationship with brine salinity. We suggest that dynamic migration pathways resulting from geological structure are significantly important to increase CO sub(2) solubility trapping potential in geological storage of CO sub(2).