Stevensite in the modern thrombolites of Lake Clifton, Western Australia: A missing link in microbialite mineralization?

Abstract

Research Article| July 01, 2014 Stevensite in the modern thrombolites of Lake Clifton, Western Australia: A missing link in microbialite mineralization? Robert V. Burne; Robert V. Burne 1Research School of Earth Sciences, Australian National University, Canberra, ACT 0200, Australia Search for other works by this author on: GSW Google Scholar Linda S. Moore; Linda S. Moore 2Department of Microbiology and Immunology, University of Western Australia, Crawley, WA 6009, Australia †Deceased Search for other works by this author on: GSW Google Scholar Andrew G. Christy; Andrew G. Christy 1Research School of Earth Sciences, Australian National University, Canberra, ACT 0200, Australia3Centre for Advanced Microscopy, Australian National University, Canberra, ACT 0200, Australia Search for other works by this author on: GSW Google Scholar Ulrike Troitzsch; Ulrike Troitzsch 1Research School of Earth Sciences, Australian National University, Canberra, ACT 0200, Australia Search for other works by this author on: GSW Google Scholar Penelope L. King; Penelope L. King 1Research School of Earth Sciences, Australian National University, Canberra, ACT 0200, Australia Search for other works by this author on: GSW Google Scholar Anna M. Carnerup; Anna M. Carnerup 4Lithicon, Suite 2, Ground Floor, 73 Northbourne Avenue, Canberra, ACT 2600, Australia Search for other works by this author on: GSW Google Scholar P. Joseph Hamilton P. Joseph Hamilton 4Lithicon, Suite 2, Ground Floor, 73 Northbourne Avenue, Canberra, ACT 2600, Australia Search for other works by this author on: GSW Google Scholar Geology (2014) 42 (7): 575–578. https://doi.org/10.1130/G35484.1 Article history received: 18 Jan 2014 rev-recd: 11 Apr 2014 accepted: 12 Apr 2014 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 Robert V. Burne, Linda S. Moore, Andrew G. Christy, Ulrike Troitzsch, Penelope L. King, Anna M. Carnerup, P. Joseph Hamilton; Stevensite in the modern thrombolites of Lake Clifton, Western Australia: A missing link in microbialite mineralization?. Geology 2014;; 42 (7): 575–578. doi: https://doi.org/10.1130/G35484.1 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 Microbialites form the earliest macroscopic evidence of life, and have always been important in particular aquatic ecosystems. They demonstrate the remarkable ability of microorganisms to provide the foundation for structures that can rival coral reefs in size. Microbialites are generally assumed to form by microbial trapping and binding of detrital grains, by carbonate organomineralization of microbial biofilms, or by inorganic mineralization around microbial templates. Here we present a significant discovery that modern thrombolitic microbialites in Lake Clifton, Western Australia, gain their initial structural rigidity from biofilm mineralization by the trioctahedral smectite mineral stevensite. This nucleates in and around microbial filament walls when biological processes suppress carbon and Ca activities, leaving Mg to bind with silica and form a microporous framework that replaces and infills the filament web. After microbial materials are entombed, local carbon and Ca activities rise sufficiently for aragonite microcrystals to grow within the stevensite matrix and perhaps replace it entirely, with eradication of biogenic textural features. This may explain why many ancient microbialite carbonates lack clear evidence for biogenicity. Stevensite may provide the missing link between microbial organomineralization and subsequent abiotic calcification. You do not have access to this content, please speak to your institutional administrator if you feel you should have access.