The Midwest Regional Carbon Sequestration Partnership (MRCSP) has incorporated the work of geologic research teams (Geoteams) in its regional characterization, project planning and carbon dioxide (CO<
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) injection implementation work since the partnership was established by the U.S. Department of Energy (DOE) in 2003. Over this 16-year period, the cohort of Geoteams has grown from five to ten states and has contributed to the characterization of geologic sequestration opportunities, refinement of reservoir and seal data, and supported injection efforts through both predictive and post-injection assessments. This report details the work led by the Ohio Department of Natural Resources, Division of Geological Survey to evaluate the structure of nine formations in the Appalachian Basin of Ohio to assess seal integrity and whether carbon dioxide (CO<
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) migration pathways could pose a potential risk. As part of Phase II MRCSP work, the Pennsylvania Geological Survey led the characterization of the Llandovery Silurian (?middle Silurian?) to Middle Devonian regional geologic characterization CO<
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utilization and storage. This preliminary assessment included generalized, regional-scale mapping, as well as the development of relatively coarse structure and isochore maps of stratigraphic intervals of interest for the Appalachian Basin. Because this stratigraphic interval offers several enhanced oil recovery targets and secondary targets for CO<
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storage, the Ohio Geological Survey undertook efforts in Phase III to characterize the Ohio?s portion of the Appalachian Basin more precisely and to resolve inconsistencies within Ohio?s formation tops. This study refined the subsurface correlations of the Silurian-through-Devonian stratigraphic section in Ohio. Higher-resolution isochore mapping of the CO<
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storage reservoirs and seals provides greater detail of potential high-porosity zones and potential structural influence on the interval.