The U.S. Geological Survey (USGS) recently completed an evaluation of the technically accessible storage resource (TA_SR) for carbon dioxide (CO₂) for 36 sedimentary basins in the onshore areas and State waters of the United States. The TA_SR is an estimate of the geologic storage resource that may be available for CO₂ injection and storage and is based on current geologic and hydrologic knowledge of the subsurface and current engineering practices. By using a geology-based probabilistic assessment methodology, the USGS assessment team members obtained a mean estimate of approximately 3,000 metric gigatons (Gt) of subsurface CO₂ storage capacity that is technically accessible below onshore areas and State waters; this amount is more than 500 times the 2011 annual U.S. energy-related CO₂ emissions of 5.5 Gt (U.S. Energy Information Administration, 2012, http://www.eia.gov/environment/emissions/carbon/).
In 2007, the Energy Independence and Security Act (Public Law 110–140) directed the U.S. Geological Survey to conduct a national assessment of geologic storage resources for CO₂ in consultation with the U.S. Environmental Protection Agency, the U.S. Department of Energy, and State geological surveys. The USGS developed a methodology to estimate storage resource potential in geologic formations in the United States (Burruss and others, 2009, USGS Open-File Report (OFR) 2009–1035; Brennan and others, 2010, USGS OFR 2010–1127; Blondes, Brennan, and others, 2013, USGS OFR 2013–1055). In 2012, the USGS completed the assessment, and the results are summarized in this Fact Sheet and are provided in more detail in companion reports (U.S. Geological Survey Geologic Carbon Dioxide Storage Resources Assessment Team, 2013a,b; see related reports at right).
The goal of this project was to conduct an initial assessment of storage capacity on a regional basis, and results are not intended for use in the evaluation of specific sites for potential CO₂ storage. The national assessment was a geology-based examination of all sedimentary basins in the onshore and State waters area of the United States that contain storage assessment units (SAUs) that could be defined according to geologic and hydrologic characteristics. Although geologic storage of CO₂ may be possible in some areas not assessed by the USGS, the SAUs identified in this assessment represent those areas within sedimentary basins that met the assessment criteria. A geologic description of each SAU was prepared; descriptions for SAUs in several basins are in Warwick and Corum (2012, USGS OFR 2012–1024).