A comparison of carbon dioxide storage resource estimate methodologies for a regional assessment of the Northern Niagaran Pinnacle Reef Trend in the Michigan Basin

The Northern Niagaran Pinnacle Reef Trend has more than 800 identified Silurian-aged pinnacle reefs in the Michigan Basin. The reefs have a long history of oil and gas production, gas storage, and more recently successful CO2-enhanced oil recovery (EOR) operations. These fields provide an excellent opportunity to evaluate the geologic variability in complex carbonate reservoirs and its impact on carbon capture, utilization, and storage feasibility. A comprehensive database was built that identifies reefs and links key reservoir attributes to each field. Novel methodologies and techniques were developed to analyze hundreds of fields for CO2 storage and EOR options. This included a regional static earth model to compute volumetric-based resource estimates, fluid substitution to estimate storage resources from oil and gas production, and proximity analysis–based weighting of reefs to predict reservoir performance metrics and estimate EOR. Lastly, an enhanced storage scenario of maximizing a reef’s storage potential at the end of a CO2-EOR life cycle was evaluated.