In what they call the "first-ever detailed national geologic carbon sequestration assessment," the newly released USGS report National Assessment of Geologic Carbon Dioxide Storage Resources—Summary omits the CO2 sequestration potential in Arizona. One of those studies was funded by USGS and delivered to them about 18 months ago.
The news release from USGS says "The United States has the potential to store a mean of 3,000 metric gigatons of carbon dioxide (CO2) in geologic basins throughout the country, according to the first-ever detailed national geologic carbon sequestration assessment released today by the U.S. Geological Survey (USGS). The assessment comes on the heels of a national plan to combat climate change announced by President Obama yesterday."
AZGS has published 8 studies on CO2 storage potential, with two others in final review:
Gootee, B.F., 2013. Geologic evaluation of Yuma Basin for carbon
dioxide sequestration potential. Arizona Geological Survey Open File Report,
OFR-13-04, 17 p.,
Gootee,
B.F., 2013. An Evaluation of Carbon Dioxide Sequestration Potential in Mohawk
Basin, Gila River Trough, Southwestern Arizona. Arizona Geological Survey Open File
Report, OFR-13-02, 8 p.,
Gootee,
B.F., 2012. Geologic Evaluation of the Tucson Basin for Carbon Dioxide
Sequestration Potential. Arizona Geological Survey Open File Report, OFR 12-40,
v 1.0, 11 p., 3 plates,
Gootee,
B.F., M.K. Mahan and D.S. Love, 2012. A Summary of Salinities in Arizona’s Deep
Groundwater. Arizona Geological Survey Open File Report, OFR-12-26, 23 p., http://repository.azgs.az.gov/uri_gin/azgs/dlio/1458
Gootee,
B.F., 2012. Geologic Evaluation of the Willcox Basin for Carbon Dioxide
Sequestration. Arizona Geological Survey Open File Report, OFR-12-03, 10 page
report, 2 map plates, 4 appendices, http://repository.azgs.az.gov/uri_gin/azgs/dlio/1399
Gootee,
B.F., 2012. Geologic Evaluation of the Safford Basin for Carbon Dioxide
Sequestration Potential. Arizona Geological Survey Open-File Report, OFR-12-01,
71 p. with 3 appendices, one map sheet with geologic cross sections, http://repository.azgs.az.gov/uri_gin/azgs/dlio/1388
Rauzi, S.L.
and J.E. Spencer, 2012. An Evaluation of CO2 Sequestration Potential of Paleozoic
Sandstone Units, Northeastern Arizona. Arizona Geological Survey Open File
Report, OFR-12-10, 24p., http://repository.azgs.az.gov/uri_gin/azgs/dlio/1460
Rauzi, S. and Spencer, J.E., 2009, Carbon Sequestration Potential at the 1 Alpine-Federal Site in East-Central Arizona. Arizona Geological Survey Open-File Report, OFR-09-02, 6 p.
Spencer, J.E., 2011. Preliminary Evaluation of Cenozoic Basins in Arizona for CO2 Sequestration Potential. Arizona Geological Survey Open-File Report, OFR-11-05, 14 p., http://repository.azgs.az.gov/uri_gin/azgs/dlio/1388
Gootee, B.F., In review, An Evaluation of Carbon Dioxide Sequestration
Potential in the Luke Basin, South-Central Arizona. Arizona Geological Survey
Open File Report, OFR-13-05, 10 p., 2 map plates and 2 appendices.
Ref: U.S. Geological Survey Geologic Carbon Dioxide
Storage Resources Assessment Team, 2013, National assessment of geologic
carbon dioxide storage resources—Summary: U.S. Geological Survey Fact
Sheet 2013–3020, 6 p., http://pubs.usgs.gov/fs/2013/3020/.
I contacted Peter Warwick, at the USGS about the Arizona data. He provided a thoughtful and detailed response:
ReplyDeleteThank you for your note. In order to complete the national CO2 storage assessment within the short time frame required by the Congressional legislation (2.5 years), we had to make relatively rapid decisions about many stratigraphic units in sedimentary basins throughout the United States. Also, similar to other national assessments (oil and gas, geothermal, etc), we created a set of assessment criteria. For this assessment, those criteria included minimum storage area, minimum porosity, minimum total dissolved solids, minimum and maximum depth cut offs, and so on.
The basins within Arizona are primarily within the Basin and Range and the southern Colorado Plateau. The Basin and Range of Arizona was evaluated by the USGS and was not assessed because it did not meet our size requirements. The time necessary to assess each small basin across the United States was not feasible with our time constraints. We acknowledge this point on page 2 of Circular 1386 by saying: “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.”
The data and shapefiles that you provided us for the Black Mesa basin, from the southern Colorado Plateau, were excellent. However, in our evaluation of the potential Storage Assessment Units (SAUs) the three potential storage formations and accompanying seal formations did not meet our criteria. The oldest SAU, comprised of the Tapeats Sandstone and overlying Bright Angel Shale, did not meet our criteria because of the extremely low porosity of the storage formation. The next potential SAU, comprised of the McCracken Sandstone (Storage) and the Ouray- and Elbert Limestones (Seal), was not assessed as carbonate units were not typically used as sealing units. These two limestone units were no different. The final potential SAU, the DeCelly Sandstone (Storage) and Moenkopi and Chinle Formations (Seal), were not assessed as these seal formations were not deemed adequate seals according to our criteria in any portion of the Colorado Plateau.
Over the next year, we plan to reevaluate some of the areas we assessed, or did not assess, and will update our assessment results in future reports. Thank you for sending references to the Arizona Geological Survey reports. We will use them in our future work.