Two opposing effects of sulfate reduction on carbonate precipitation in normal marine, hypersaline, and alkaline environments

Research Article| April 01, 2013 Two opposing effects of sulfate reduction on carbonate precipitation in normal marine, hypersaline, and alkaline environments Patrick Meister Patrick Meister * Max Planck Institute for Marine Microbiology, Celsiusstrasse 1, 28205 Bremen, Germany *E-mail: pmeister@mpi-bremen.de. Search for other works by this author on: GSW Google Scholar Geology (2013) 41 (4): 499–502. https://doi.org/10.1130/G34185.1 Article history received: 30 Oct 2012 rev-recd: 12 Nov 2012 accepted: 12 Nov 2012 first online: 09 Mar 2017 Cite View This Citation Add to Citation Manager Share Icon Share Facebook Twitter LinkedIn MailTo Tools Icon Tools Get Permissions Search Site Citation Patrick Meister; Two opposing effects of sulfate reduction on carbonate precipitation in normal marine, hypersaline, and alkaline environments. Geology 2013;; 41 (4): 499–502. doi: https://doi.org/10.1130/G34185.1 Download citation file: Ris (Zotero) Refmanager EasyBib Bookends Mendeley Papers EndNote RefWorks BibTex toolbar search Search Dropdown Menu toolbar search search input Search input auto suggest filter your search All ContentBy SocietyGeology Search Advanced Search Abstract Sulfate reduction has been suggested as a mechanism to induce precipitation of calcium and magnesium carbonates in marine sediments and microbial mats through most of Earth’s history. However, sulfate reduction also causes a drop in pH that favors dissolution rather than precipitation of carbonates. Model results obtained in this study show that in modern seawater, modern hypersaline water, and assumed Precambrian alkaline seawater, sulfate reduction initially lowers the saturation of carbonates due to a rapid decrease in pH. With continuing sulfate reduction, the pH stabilizes between 6.5 and 7, and carbonate saturation slowly increases as a result of increasing dissolved inorganic carbon concentration. However, sulfate reduction in surface microbial mats is not sufficient to cause such an increase in saturation. With increasing salinity, sulfate reduction becomes even less efficient to induce carbonate precipitation. In an alkaline Precambrian ocean, where large amounts of carbonate were formed, induction through sulfate reduction was entirely ineffective. Other metabolic pathways or abiotic factors must be responsible for inducing carbonate formation in microbial mats through Earth’s history. You do not have access to this content, please speak to your institutional administrator if you feel you should have access.