GEOLOGICAL SURVEY OF ALABAMA
CARBON SEQUESTRATION RESEARCH
Southeastern Regional Carbon Sequestration Partnership (SECARB Phase I)
A study sponsored by the
Project start date: 2/11/04
The southeastern United States accounts for about 40 percent of the nationŐs carbon dioxide emissions, and reducing those emissions will help offset the effects of global warming. Geologic sequestration of carbon dioxide has been identified as a viable approach to reducing greenhouse gas emissions, and the U.S. Department of Energy has established seven regional partnerships to identify and test the best prospects for carbon sequestration throughout the United States.
Phase I of the regional partnership program focused on identification and characterization of potential geologic sinks. Phase II of this program began on October 1, 2005. Phase II activities include continued characterization of promising geologic sinks and feature scaled field tests and monitoring programs to verify sequestration capacity and sink integrity.
The Geological Survey of Alabama is a member of the Southeastern Regional Carbon Sequestration Partnership (SECARB) and has completed a Phase I investigation of potential geologic carbon sinks in Alabama, Mississippi, and the Florida panhandle. Activities included compilation of a database and geographic information system (GIS) containing a broad range of information on potential geologic sinks and CO2 emission sources, which can be downloaded from the Technology Transfer section of this web page.
Potential Geologic Carbon Sinks
Three major classes of geologic carbon sinks were identified in Alabama, Mississippi, and the Florida panhandle: conventional oil and gas reservoirs, coalbed methane reservoirs, and saline aquifers. Basic data collected during Phase I of the SECARB program include geographic information, geologic information, engineering data, fluid production data, and geochemical data. Each class of sink is described briefly in the following paragraphs, and the database and GIS can be downloaded from the Technology Transfer section of this web page.
Conventional Oil and Gas Reservoirs
Injection of carbon dioxide into mature hydrocarbon reservoirs can enhance the recovery of oil and gas, thus providing economic incentive for geologic sequestration. Oil and gas fields in the Black Warrior and Gulf of Mexico basins that have produced more than 100,000 barrels of oil or 10 billion cubic feet of gas were analyzed. In the Black Warrior basin, oil reservoirs in Upper Mississippian sandstone units provide the most promising targets for carbon sequestration. The Gulf of Mexico basin contains numerous sequestration targets in sandstone and carbonate of Jurassic through Tertiary age, and some of the most attractive targets are in Cretaceous sandstone. Vertical stacking of multiple oil and gas pools facilitates diverse sequestration opportunities in the eastern Gulf of Mexico basin, where CO2-enhanced oil recovery has already been proven to be economically viable.
Coalbed Methane Reservoirs
Coalbed methane is produced from Pennsylvanian-age strata of the Pottsville Formation in the Black Warrior basin of Alabama, and injection of carbon dioxide can be used to enhance coalbed methane recovery. Pottsville coal beds are of bituminous rank, are typically between 0.3 and 3.0 meters thick, and are distributed through 700 to 1,500 meters of section. A recent assessment by the Geological Survey of Alabama indicates that more than 5.9 trillion cubic feet of carbon dioxide can be sequestered in the established coalbed methane fields and that enhanced recovery operations has potential to increase coalbed methane reserves by more than 20 percent. Additional sequestration potential exists in low-rank coal in Tertiary-age strata (Midway and Wilcox Groups) of the Gulf of Mexico basin, but little information exists on the distribution, thickness, and reservoir quality of coal in this area.
Exceptional sequestration capacity exists in saline aquifers, although the prospects for economic benefit associated with enhanced resource recovery are limited. Major saline aquifers exist in the Black Warrior and Gulf of Mexico basins. In general, high potential for saline aquifer storage of carbon dioxide exists in the same formations that have produced conventional oil and gas. Drilling in saline aquifers is limited outside of major oil and gas production fairways, and most of the geologic and geochemical data given in the database are from oil and gas fields. Importantly, saline aquifers offer extensive sequestration capacity in areas where mature oil and gas reservoirs may not be available for enhanced recovery operations. In addition, saline aquifers may be stacked above or below oil and gas reservoirs and thus can provide sequestration capacity to augment storage associated with enhanced hydrocarbon recovery.
This project included a vigorous technology transfer program designed to support the demonstration and commercialization of carbon sequestration technology. Results have been and are being presented at technical meetings and workshops and have been incorporated into the national carbon sequestration database and GIS (NATCARB). A link to download the final ArcView GIS product for Alabama, Mississippi, and the Florida panhandle is given below:
Pashin, J. C., and Payton, J. W., 2005, Geological sinks for carbon sequestration in Alabama, Mississippi, and the Florida panhandle: Alabama Geological Survey, Final Report to Southern States Energy Board, Subgrant SSEB-NT41980-997-GSA-2004-00 (.zip archive; 62.4 Mb; requires ArcView 3.2 or better).
Screenshot 1: Data coverage for conventional oil and gas reservoirs, coalbed methane reservoirs, saline aquifers, and coal-fired power plants.
Screenshot 2: Data coverage for conventional oil and gas reservoirs.
Screenshot 3: Sample data table for a conventional oil reservoir.
Jack C. Pashin, Geological Survey of Alabama (Principal investigator; coal and petroleum geology)
J. Wayne Payton, Geological Survey of Alabama (Petroleum geology)
Marty G. Gates, Geological Survey of Alabama (Geographic information systems)
Contracting Officer Representatives
Karen Cohen, National Energy Technology Laboratory
Jerry Hill, Southern States Energy Board
This material is based upon work supported by the Department of Energy, under Award No. DE-FG26-03NT41980. However, any findings, conclusions, or recommendations expressed herein are those of the authors and do not necessarily reflect the views of the DOE.
The Geological Survey of Alabama (GSA) makes every effort to collect, provide, and maintain accurate and complete information. However, data acquisition and research are ongoing activities of GSA, and interpretations may be revised as new data are acquired. Therefore, all information made available to the public by GSA should be viewed in that context. Neither the GSA nor any employee thereof makes any warranty, expressed or implied, or assumes any legal responsibility for the accuracy, completeness, or usefulness of any information, apparatus, product, or process disclosed in this report. Conclusions drawn or actions taken on the basis of these data and information are the sole responsibility of the user.