A Sensitivity Study on Regional Pressure Buildup from Large-Scale CO2 Storage Projects

Abstract

AbstractSeveral international researchers have in recent years evaluated the potentially far-reaching brine pressurization and migration processes resulting from the storage of large volumes of CO2 in deep saline aquifers (e.g, ). Predictive simulations have been conducted for idealized geologic systems as well as for large sedimentary basins with promising CO2 sequestration potential. In contrast to the latter studies, which often involve laterally extensive sediments with large storage capacity, we investigate here the potential impact of geologic carbon sequestration in a partially compartmentalized sandstone basin in the Southern San Joaquin Valley in California, USA. The expected CO2 plume behavior and injection-related pressure perturbation are modeled for a hypothetical CO2 sequestration project situated in the center of the basin. Uncertainty about fault behavior is addressed by assessing two distinctive fault property scenarios. A systematic sensitivity study is conducted for each scenario to identify key parameters and processes affecting pressure buildup and brine migration. We distinguish in this sensitivity study between the near-field region comprising the projected size of the CO2 plume, where hydrogeological properties are expected to be better constrained, and the far-field region comprising the projected extent of pressure buildup, where parameter uncertainty can be quite high