The Midwest Regional Carbon Sequestration Partnership (MRCSP) was founded in 2003 as part of the U.S. Department of Energy?s (DOE?s) Regional Carbon Sequestration Partnership initiative. Since its founding, MRCSP has made significant strides toward making CCUS a viable option for states in the region. The public/private consortium, funded through the DOE Regional Carbon Sequestration Initiative, brings together nearly 40 industry partners and 10 states. Battelle, as the project lead, oversees research, development and operations and coordinates activities among the partners. The incremental, phased approach has built a valuable knowledge base for the industry and paved the way for commercial-scale adoption of CCUS technologies. From 2008 to 2020, MRCSP Phase III focused on the development of large-scale injection projects. This report is part of a series of reports prepared under the Midwestern Regional Carbon Sequestration Partnership (MRCSP) Phase III (Development Phase). These reports summarize and detail the findings of the work conducted under the Phase III project. This report compiles the results of geologic characterization of late-stage reefs, active EOR reefs, and new EOR reefs in the Northern Niagaran Pinnacle Reef Trend (NNPRT) in Michigan to demonstrate developed methodologies, geologic variability, and reservoir potential for CO<
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storage. Conducting CO<
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injection and monitoring in these settings provide significant insights for addressing the project objectives: assessment of injectivity in complex carbonate reef deposits
assessing CO<
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trapping mechanisms in a closed reservoir system
assessing any final oil recovery from transitional or residual oil zones in a field where CO<
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flooding is nearing completion
evaluating the transition from EOR to storage of CO<
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assessing regional commercialization
assessing new technologies for tracking CO<
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, brine, and oil movements underground
and monitoring options in a closed reservoir with oil, residual oil, and water zones.