A Texas Geologic Carbon Repository Concept beneath Submerged State Lands
Governments and industries worldwide are preparing for a transition to energy economies that seek to incorporate a variety of cleaner technologies at commercial scale. Texas has always been a global energy leader, and it now has the opportunity to prepare to lead the nation and the world by creating the proper physical, economic, and regulatory conditions for large-scale clean fossil energy production. An instrumental step is establishing a subsurface geologic carbon repository in State-owned and managed offshore lands. The State of Texas owns approximately 6,400 square miles of offshore land. Of this, some 2,500 square miles (40%) exists in bays, estuaries, and passes, in addition to approximately 3,800 square miles (60%) in the Gulf of Mexico within the 3- to 10-mile delineation of Federal waters. Many of these lands are currently leased for hydrocarbon production or other activities, but these leases constitute fewer than 20% of the State-owned lands and would not themselves be off-limits to potential brine-sequestration projects. Much State-owned submerged land is currently underutilized and could be considered for CCS activities and repository locations. Capacity for storing CO2 in brine reservoirs beneath offshore State lands has been the focus of a preliminary assessment by the Gulf Coast Carbon Center at the Bureau. Initial estimates of brine-reservoir capacity in submerged State lands may be approximately 100 years’ worth of current statewide CO2 emissions, but more work is needed to refine these estimates. Benefits from such use of State lands include increased revenue from lease sales, CO2-EOR, and the stimulation of an existing and capable workforce while creating new jobs, relying on in-place expertise and educational curricula in engineering, geoscience, and related business and legal fields that have supported Texas economic development for decades. The intent of this research is to: 1) document the capacity of a number of specific repository candidate storage sites; 2) provide rigorous measures of the efficiency of storage (percent of available pore volume utilized); 3) Allow extrapolation of this efficiency to provide an improved capacity assessment for the entire submerged State lands region; and 4) provide a case study that sets the standard nationally and internationally for this type of proactive, high-quality storage development.
AAPG Search and Discovery Article #90090©2009 AAPG Annual Convention and Exhibition, Denver, Colorado, June 7-10, 2009