Formation of aragonite cement by nannobacteria in the Great Salt Lake, Utah

Research Article| August 01, 1996 Formation of aragonite cement by nannobacteria in the Great Salt Lake, Utah Vicki A. Pedone; Vicki A. Pedone 1Department of Geological Sciences, California State University, Northridge, California 91330-8266 Search for other works by this author on: GSW Google Scholar Robert L. Folk Robert L. Folk 2Department of Geological Sciences, University of Texas at Austin, Austin, Texas 71713-7909 Search for other works by this author on: GSW Google Scholar Author and Article Information Vicki A. Pedone 1Department of Geological Sciences, California State University, Northridge, California 91330-8266 Robert L. Folk 2Department of Geological Sciences, University of Texas at Austin, Austin, Texas 71713-7909 Publisher: Geological Society of America First Online: 02 Jun 2017 Online ISSN: 1943-2682 Print ISSN: 0091-7613 Geological Society of America Geology (1996) 24 (8): 763–765. https://doi.org/10.1130/0091-7613(1996)024<0763:FOACBN>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 Vicki A. Pedone, Robert L. Folk; Formation of aragonite cement by nannobacteria in the Great Salt Lake, Utah. Geology 1996;; 24 (8): 763–765. doi: https://doi.org/10.1130/0091-7613(1996)024<0763:FOACBN>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 Brine-shrimp egg cases in growth cavities in modern stromatolites in the Great Salt Lake, Utah, are replaced by aragonite and cemented together by aragonite cement. The fabric of the cement changes dramatically as the distance from the egg case increases. The cement within 50 to 70 μm of the egg case exhibits a random fabric of 10 to 20 μm equant crystals. The surface of the cement is covered by bead-like bumps, 0.1 μm in diameter, interpreted as nannobacteria. Overlying the random, "beaded" fabric with a relatively abrupt transition are epitaxial, prismatic aragonite crystals that have smooth crystal surfaces lacking bead-like bodies. The smooth-surfaced prismatic aragonite crystals are interpreted to be "normal" abiotic precipitates, whereas the "beaded" microspar is interpreted to result from biotic processes, where the nannobacteria serve as catalysts for creation of the cement. A population explosion of bacteria occurs as the organic material of egg case rots, which alters the microchemical environment and induces a rapid precipitation of aragonite, enclosing tens of thousands of nannobacteria. As the organic material is destroyed, reproduction of bacteria slows and epitaxial, prismatic aragonite crystals nucleate and grow abiotically on the structureless, "biotic" layer. 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.