Geologic framework for the national assessment of carbon dioxide storage resources: Arkoma Basin, Kansas Basins, and Midcontinent Rift Basin study areas

2007 Energy Independence and Security Act (Public Law 110–140) directs the U.S. Geological Survey (USGS) to conduct a national assessment of potential geologic storage resources for carbon dioxide (CO₂). The methodology used by the USGS for the national CO₂ assessment follows that of previous USGS work. This methodology is non-economic and intended to be used at regional to subbasinal scales. This report identifies and contains geologic descriptions of three storage assessment units (SAUs) in Upper Cambrian to Mississippian sedimentary rocks within the Arkoma Basin study area, and two SAUs in Upper Cambrian to Mississippian sedimentary rocks within the Kansas Basins study area. The Arkoma Basin and Kansas Basins are adjacent with very similar geologic units; although the Kansas Basins area is larger, the Arkoma Basin is more structurally complex. The report focuses on the characteristics, specified in the methodology, that influence the potential CO₂ storage resource in the SAUs. Specific descriptions of the SAU boundaries as well as their sealing and reservoir units are included. Properties for each SAU, such as depth to top, gross thickness, porosity, permeability, groundwater quality, and structural reservoir traps, are usually provided to illustrate geologic factors critical to the assessment. Although assessment results are not contained in this report, the geologic information herein was employed, as specified in the USGS methodology, to calculate a probabilistic distribution of potential storage resources in each SAU. The Midcontinent Rift Basin study area was not assessed, because no suitable storage formations meeting our size, depth, reservoir quality, and regional seal guidelines were found. Figures in this report show study area boundaries along with the SAU boundaries and cell maps of well penetrations through sealing units into the top of the storage formations. The cell maps show the number of penetrating wells within one-square mile and are derived from interpretations of incompletely attributed well data and from a digital compilation that is known not to include all drilling. The USGS does not expect to know the location of all wells and cannot guarantee the amount of drilling through specific formations in any given cell shown on the cell maps.