Evaluating the impact of aquifer layer properties on geomechanical response during CO2 geological sequestration

Numerical models play an essential role in understanding the facts of carbon dioxide (CO2) geological sequestration in the life cycle of a storage reservoir. We present a series of test cases that reflect a broad and realistic range of aquifer reservoir properties to systematically evaluate and compare the impacts on the geomechanical response to CO2 injection. In this study, a coupled hydro-mechanical model was applied to simulate the sequestration process, and a quasi-Monte Carlo sampling method was employed to efficiently sample the value of aquifer properties and geometry parameters. Through quantitative sensitivity analysis, the impacts of all the input parameters are ranked. Aquifer permeability was found to be of significant importance to the geomechanical response to the injection. To study the influence of uncertainty of the permeability distribution in the aquifer, an additional series of tests is presented, based on a default permeability distribution site sample with various distribution deviations generated by the Monte Carlo sampling method. The results of the test series show that the uncertainty of permeability distributions significantly affect the displacement and possible failure zone.

► An efficient numerical simulation tool for CO2 sequestration uncertainty quantification.
► Sensitivity analysis for geomechanical response to CO2 sequestration.
► Aquifer permeability is of significant importance to the geomechanical response.
► Structure of layering aquifer permeability distributions impact the failure zone.