GEOLOGIC CHARACTERIZATION AND ASSESSMENT OF THE GEOLOGIC CARBON SEQUESTRATION RESOURCES IN THE CHEROKEE BASIN OF OKLAHOMA

The anthropogenic emission of carbon dioxide is a primary driver for present-day global warming and is expected to result in considerable hazardous climatic change with dangerous societal and environmental risks. Carbon capture and sequestration (CCS) is a potential and promising option for greenhouse gas mitigation. The present study aims to develop a geologic characterization and assessment of the potential geologic carbon storage resources in the Cherokee Basin of Oklahoma. The data used include: Well logs, induced seismicity data, faulting maps, and waste-water injection data. The workflow started with a regional screening and characterization of the entire Cherokee Basin of Oklahoma to identify the sub-regions of interest that are potentially suitable for CO₂ storage. The screening criteria utilized include reservoir-seal integrity and continuity, depth to the sealing layer, faulting intensity, induced seismicity, earthquakes, and groundwater aquifers. The reservoir parameters are then determined for the potential sinks to assess the storage resources. In this regard, more than 12,000 well logs representing 3652 wells that cover the Cherokee Basin were studied to figure out the stratigraphic framework, structural setting, and the petrophysical characteristics. Preliminary results reveal the identification of potential geologic carbon sequestration sites in Okmulgee and Osage counties. Other counties in the basin are still under assessment. In Okmulgee, the potential storage sinks are represented by stacked reservoirs that include the Cambrian – Ordovician Arbuckle Group (dolomite) and the sandstone formations of the Ordovician Simpson Group. The potential seals include the Ordovician Sylvan shale, the tight carbonates of the Viola Group, the Devonian Woodford shale, and shale units of the Simpson Group. In Osage and Kay counties, the potential storage sink is the Arbuckle dolomite (storage capacity P50% of 180,180,000t). Potential seals are the Woodford shale and the tight Mississippian limestone. Resource assessment in Okmulgee reveals that the Arbuckle and Simpson Groups in the central to eastern part of Okmulgee County provide a stacked succession of reservoirs with a cumulative storage capacity P50% of 75,870,000t. The Arbuckle and Simpson Groups in the southern part of Okmulgee provide a cumulative storage capacity P50% of 20,979,000t.