Schaef, H. Todd¹, B. Peter McGrail¹, Stephen P. Reidel¹ 
(1) Pacific Northwest National Laboratory, Richland, WA

ABSTRACT: Geologic Sequestration of CO₂ in Basalt Formations

Capture of CO₂ from flue gases and subsequent geologic sequestration is being widely considered for controlling anthropogenic CO₂ emissions. Massive flood basalt formations exist worldwide and have unique chemical properties that could potentially convert all the injected CO₂ to solid mineral form, effectively isolating it from the atmosphere. Under certain reservoir conditions, CO₂ reacts with the minerals in the basalt releasing cations (Ca, Fe, and Mg) into solution, which precipitate as a carbonate mineral. Laboratory tests have confirmed the formation of carbonate coatings when basalt samples collected from Washington State were exposed to supercritical CO₂. Detailed examination of the reacted basalt shows that preferential dissolution of the glassy mesostasis and olivine in the basalt are the principal mineral phases responsible for the observed rapid carbonate mineralization.

AAPG Search and Discovery Article #90026©2004 AAPG Annual Meeting, Dallas, Texas, April 18-21, 2004.