Dynamic modeling to understand pressure response from oil production and CO2 injection in a depleted pinnacle reef reservoir: Manual calibration using simplified resolution of reservoir heterogeneity

Abstract The Midwest Regional Carbon Sequestration Partnership has been investigating various reservoir characterization and modeling technologies as part of its commercial-scale implementation of carbon dioxide injection for geologic storage in multiple Silurian carbonate pinnacle reefs in northern Michigan, USA. This paper presents a discussion of the reservoir modeling study that was conducted for history-matching oil production and CO2 injection responses, forecasting CO2 plume migration and estimating associated storage to characterize the closed, depleted Dover-33 reef which has undergone extensive primary and secondary production. Dynamic modeling using equivalent simplified descriptions of reservoir heterogeneity were found to be numerically efficient and successfully explained the observed pressure buildup in the reef during the MRCSP CO2 injection phase. The validated history matched models are extremely useful for potential predictive modeling for considering operational optimization and evaluating subsequent production scenarios relevant to the reef.