CO2 Injection and Reservoir Characterization: An Integrated Petrographic and Geochemical Study of the Frio Formation, Texas
Ball State University, Department of Geology Muncie, Indiana; [email protected]
Located in the subsurface of the Gulf Coast, a region responsible for approximately 16 percent of national CO2 release, the Frio Formation is currently the focus of CO2 sequestration experiments by the Gulf Coast Carbon Center (GCCC). To assess the Frio Formation as a repository for anthropogenic CO2, an integrated petrographic and geochemical analysis of core samples is being completed to determine the effects of CO2 injection on rock-water interaction in the sandstone reservoir. This study examines the mineralogical characteristics of the Frio “C” and “B” sandstones at the experiment site to determine potential sources of ions put into solution as a result of increased CO2 concentrations. Formation waters, sampled during the sequestration experiment, exhibited a rapid decrease in pH and increases in alkalinity and dissolved metals. The addition of XRD and SEM analyses, as well as thin-section descriptions to data collected by the GCCC is essential in understanding the chemical changes occurring in the formation as a result of increasing CO2. The integration of these data will lead to the creation of a model for simulating the Frio’s chemical reactive properties in response to increased CO2 concentrations. This research supports the GCCC’s efforts in CO2 sequestration and their ultimate goal of atmospheric CO2 reduction.
AAPG Search and Discovery Article #90083 © 2008 AAPG Foundation Grants in Aid