Simulation and 4D seismic studies of pressure management and CO2 plume control by means of brine extraction and monitoring at the Devine Test Site, South Texas, USA

Within the context of CO2 geological storage, excessive pressure build-up is undesirable because it increases the risks of CO2 plume leaks into unwanted zones, reduces the storage capacity of the formation, and can limit the life of a storage project. In this study, we designed a brine extraction field pilot project for pressure management and plume control in the Hosston Formation at the Devine Test Site (DTS) in Texas. We investigated the possibility of using seismic and tracer data to monitor pressure front and injected fluids plume. Seismic surveys provide the volumetric coverage needed to understand the 3D subsurface fluid and pore pressure front movement; however, the limit of seismic detectability may be influenced by Hosston Formation initial pore pressure. The range of minimum pore pressure increase needed to produce detectable P-wave and S-wave seismic velocities is investigated. Simulation study of active pressure management system (APMS) and passive pressure management system (PPMS) at the DTS is performed using the numerical simulator CMG-STARS to demonstrate the possibility of controlling pressure build up in the storage formation. The estimation of pore pressure increase from flow simulations will help us to understand if the pressure changes during brine injection and extraction can be detected using seismic response. Study findings show that 4D seismic is an appropriate monitoring tool considering the level of expected increase in pressure at the DTS and that, as expected, brine extraction is successful in controlling the pressure build up and potentially can steer the plume at the DTS. (C) 2017 Society of Chemical Industry and John Wiley & Sons, Ltd.