Evaluation of potential impacts of geologic carbon sequestration using numerical simulation

A mathematical sedimentary basin model, including full coupling of multiphase CO₂-groundwater flow, heat flow, and rock deformation, was used to evaluate effects of CO₂ injection on fluid pressures and rock strain. Residence times and migration patterns of CO₂ in possible brine reservoir storage sites were also analyzed. Study areas include the Uinta and Paradox basins of Utah, and the Permian basin of west Texas. Sustained injection of CO₂ might encounter significant brine displacement out of adjacent sealing layers, depending on the injection history, initial brine composition, and hydrologic properties of both reservoirs and seals. Model simulations also suggested that injection could induce abnormally high fluid pressures, or overpressures. Injection-induced overpressures may migrate, and effective stresses may follow this migration under some conditions, as well as associated rock strain. Such strain migration may lead to induced or reactivated fractures or faults, but can be controlled through reservoir engineering. This is an abstract of a paper presented at the 2008 AIChE Spring National Meeting (New Orleans, LA 4/6-10/2008).