Oxygen isotope composition of Holocene dolomite formed in a humid hypersaline setting

Abstract

Research Article| July 01, 1992 Oxygen isotope composition of Holocene dolomite formed in a humid hypersaline setting R. P. Major; R. P. Major 1Bureau of Economic Geology, University of Texas, Austin, Texas 78713-7508 Search for other works by this author on: GSW Google Scholar R. Michael Lloyd; R. Michael Lloyd 25925 Kirby Drive, Suite 208, Houston, Texas 77005-3144 Search for other works by this author on: GSW Google Scholar F. Jerry Lucia F. Jerry Lucia 1Bureau of Economic Geology, University of Texas, Austin, Texas 78713-7508 Search for other works by this author on: GSW Google Scholar Geology (1992) 20 (7): 586–588. https://doi.org/10.1130/0091-7613(1992)020<0586:OICOHD>2.3.CO;2 Article history first online: 02 Jun 2017 Cite View This Citation Add to Citation Manager Share Icon Share Facebook Twitter LinkedIn MailTo Tools Icon Tools Get Permissions Search Site Citation R. P. Major, R. Michael Lloyd, F. Jerry Lucia; Oxygen isotope composition of Holocene dolomite formed in a humid hypersaline setting. Geology 1992;; 20 (7): 586–588. doi: https://doi.org/10.1130/0091-7613(1992)020<0586:OICOHD>2.3.CO;2 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 Holocene dolomite forming in supratidal carbonate sediments of Bonaire, Netherlands Antilles, is precipitated from hypersaline fluids in which the Mg:Ca ratio is elevated by evaporation and gypsum precipitation. Kinetic effects and water-vapor exchange between the humid atmosphere and hypersaline brines limit the δ18O values of the brines to between +0.7‰ and +2.1‰ standard mean ocean water. The mean δ18O value of dolomite is +1.0‰ Peedee belemnite (n = 8), which is lower than values of dolomite precipitated from hypersaline brines in less humid environments. Bonaire dolomite is also isotopically lighter than dolomites interpreted to have formed in normal marine waters and mixed marine and/or meteoric waters. Calculated fractionation between dolomite and calcite formed from Bonaire brines is between 1.5‰ and 3.5‰. The high end of this range is consistent with previously proposed mineralogic fractionations of 3‰ ±1‰ and 3.2‰ between dolomite and calcite. This content is PDF only. Please click on the PDF icon to access. First Page Preview Close Modal You do not have access to this content, please speak to your institutional administrator if you feel you should have access.