Microbial action formed Jurassic Mn-carbonate ore deposit in only a few hundred years (Úrkút, Hungary)

Abstract

Research Article| October 01, 2012 Microbial action formed Jurassic Mn-carbonate ore deposit in only a few hundred years (Úrkút, Hungary) Márta Polgári; Márta Polgári * 1Institute for Geochemical Research, Hungarian Academy of Sciences, Budaörsi str. 45, 1112 Budapest, Hungary *E-mails : [e-mail]; [e-mail]. Search for other works by this author on: GSW Google Scholar J.R. Hein; J.R. Hein * 2U.S. Geological Survey, 400 Natural Bridges Drive, Santa Cruz, California 95060, USA *E-mails : [e-mail]; [e-mail]. Search for other works by this author on: GSW Google Scholar A.L. Tóth; A.L. Tóth 3Research Institute for Technical Physics and Materials Science, HAS, Konkoly Thege str. 29-33, 1121 Budapest, Hungary Search for other works by this author on: GSW Google Scholar E. Pál-Molnár; E. Pál-Molnár 4Szeged University, Department of Mineralogy, Geochemistry and Petrology, Egyetem str. 2-6, 6702 Szeged, Hungary Search for other works by this author on: GSW Google Scholar T. Vigh; T. Vigh 5Mangán Ltd, Úrkút, Külterület 1, 8409, Hungary Search for other works by this author on: GSW Google Scholar L. Bíró; L. Bíró 4Szeged University, Department of Mineralogy, Geochemistry and Petrology, Egyetem str. 2-6, 6702 Szeged, Hungary Search for other works by this author on: GSW Google Scholar K. Fintor K. Fintor 4Szeged University, Department of Mineralogy, Geochemistry and Petrology, Egyetem str. 2-6, 6702 Szeged, Hungary Search for other works by this author on: GSW Google Scholar Author and Article Information Márta Polgári * 1Institute for Geochemical Research, Hungarian Academy of Sciences, Budaörsi str. 45, 1112 Budapest, Hungary J.R. Hein * 2U.S. Geological Survey, 400 Natural Bridges Drive, Santa Cruz, California 95060, USA A.L. Tóth 3Research Institute for Technical Physics and Materials Science, HAS, Konkoly Thege str. 29-33, 1121 Budapest, Hungary E. Pál-Molnár 4Szeged University, Department of Mineralogy, Geochemistry and Petrology, Egyetem str. 2-6, 6702 Szeged, Hungary T. Vigh 5Mangán Ltd, Úrkút, Külterület 1, 8409, Hungary L. Bíró 4Szeged University, Department of Mineralogy, Geochemistry and Petrology, Egyetem str. 2-6, 6702 Szeged, Hungary K. Fintor 4Szeged University, Department of Mineralogy, Geochemistry and Petrology, Egyetem str. 2-6, 6702 Szeged, Hungary *E-mails : [e-mail]; [e-mail]. Publisher: Geological Society of America Received: 14 Feb 2012 Revision Received: 10 May 2012 Accepted: 17 May 2012 First Online: 09 Mar 2017 Online ISSN: 1943-2682 Print ISSN: 0091-7613 © 2012 Geological Society of America Geology (2012) 40 (10): 903–906. https://doi.org/10.1130/G33304.1 Article history Received: 14 Feb 2012 Revision Received: 10 May 2012 Accepted: 17 May 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 Márta Polgári, J.R. Hein, A.L. Tóth, E. Pál-Molnár, T. Vigh, L. Bíró, K. Fintor; Microbial action formed Jurassic Mn-carbonate ore deposit in only a few hundred years (Úrkút, Hungary). Geology 2012;; 40 (10): 903–906. doi: https://doi.org/10.1130/G33304.1 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 The Úrkút (Hungary) manganese (Mn) ore, hosted by Jurassic black shale, was studied using high-resolution mineralogical, microtextural, and chemical methods. Two independent superimposed biostructures were identified consisting of rhythmic laminations that provide important proxies for paleoenvironments and duration of ore formation. Millimeter-scale laminae reflect a depositional series of Fe-rich biomats, mineralized microbially produced sedimentary structures. These biomats formed at the sediment-water interface under dysoxic and neutral pH conditions by enzymatic Fe2+ oxidizing processes that may have developed on a daily to weekly growth cycle. The early diagenetic sedimentary ore is composed of Ca rhodochrosite, celadonite, and smectite, and also shows a 100-μm-scale element oscillation that produces Mn(Ca)-rich and Si(Fe clay)-rich microlaminae. This microlamination may reflect a 10 h to daily rhythmicity produced by the growth of microbial communities. If true, then the giant Úrkút ore deposit may have formed over hundreds of years, rather than hundreds of thousands of years as previously thought. You do not have access to this content, please speak to your institutional administrator if you feel you should have access.