"Several bacterial species influence carbonate mineral precipitation by modifying pH, alkalinity, Ca²⁺ activity and by providing nucleation sites for mineralization. Two studies have been undertaken to explore microbial influence in the mineralization of carbonates. In the first study, the ability of sulfate-reducing bacteria (SRB) to induce carbonate mineralization was investigated as a means to enhance mineral sequestration of CO₂. Sulfate-reducing bacteria enriched from hypersaline Storr's Lake, The Bahamas; Lake Estancia, New Mexico; and Great Salt Plains Lake, Oklahoma, were tested in reactors under varying CO₂ concentrations. Carbonate mineral precipitation was achieved only in reactors with Lake Estancia SRB community and under a pCO₂ of < 20 psi. Hydrogen, lactate and formate served as electron donors for SRB. Carbon isotopic studies confirmed that carbon in the carbonate minerals was derived from electron donors, CO₂ or bicarbonate ions in the solution. Sulfate-reducing bacteria's ability to induce immobile carbonate mineralization can be potentially applied to enhance long-term storage of CO₂.
Secondly, microbially lithified, organo-sedimentary structures called microbialites in the hypersaline Storr's Lake were investigated to determine the influence of biotic and abiotic components of the lake on the microbialite formation. The lake water revealed fluctuations in several parameters depending upon rainfall and evaporation. Aragonite and Mg-calcite constituted the carbonate mineralogy of the five microbialites morphologic types examined. Microbial diversity studies by 16S rRNA gene analysis revealed high population percentages of anaerobic phototrophs, halo-respirers and sulfate-reducing bacteria and low population of cyanobacteria (3%). The fluctuating water characteristics, varied mineralogy and the low apparent abundance of cyanobacteria, makes Storr's Lake, a distinct environment to study microbial interaction with their surroundings during carbonate mineralization."--Abstract, page iv.
Wronkiewicz, David J.
Mormile, Melanie R.
Foster, Jamie S.
Geosciences and Geological and Petroleum Engineering
Ph. D. in Geology and Geophysics
National Energy Technology Laboratory (U.S.)
Missouri University of Science and Technology
Journal article titles appearing in thesis/dissertation
- Impact of elevated CO₂ concentrations on the carbonate mineral precipitation ability of sulfate-reducing bacteria and its implication for CO₂ sequestration
- Characterization of water, microbial mats and microbialites in the hypersaline environment of Storr's Lake, the Bahamas
xiii, 257 pages
Storr's Lake (Bahamas)
Lake Estancia (N.M.)
Great Salt Plains Lake (Okla.)
© 2014 Varun Gnanaprian Paul, All rights reserved.
Dissertation - Open Access
Electronic OCLC #
Paul, Varun Gnanaprian, "Biomineralization of carbonates in modern microbial sediments and its implications for CO₂ sequestration" (2014). Doctoral Dissertations. 2138.