Geological and Geotechnical Site Investigation for the Design of a CO 2 Rich Flue Gas Direct Injection and Storage Facility
With international efforts to limit anthropogenic carbon in the atmosphere, various CO 2 sequestration methods have been studied by various facilities worldwide. Basalt rock in general has been referred to as potential host material for mineral carbonation by various authors, without much regard for compositional variations due to depositional environment, subsequent metamorphism, or hydrothermal alteration. Since mineral carbonation relies on the presence of certain magnesium, calcium, or iron silicates, it is necessary to study the texture, mineralogy, petrology, and geochemistry of specific basalts before implying potential for mineral carbonation. The development of a methodology for the characterization of basalts with respect to their susceptibility for mineral carbonation is proposed to be developed as part of this research. The methodology will be developed based on whole rock data, petrography and microprobe analyses for samples from the Caledonia Mine in Michigan, which is the site for a proposed small-scale demonstration project on mineral carbonation in basalt. Samples from the Keweenaw Peninsula will be used to determine general compositional trends using whole rock data and petrography. Basalts in the Keweenaw Peninsula have been subjected to zeolite and prehnite-pumpellyite facies metamorphism with concurrent native copper deposition. Alteration was likely due to the circulation of CO 2 -rich fluids at slightly elevated temperatures and pressures, which is the process that is attempted to be duplicated by mineral carbonation.