Does gold in orogenic deposits come from pyrite in deeply buried carbon-rich sediments?: Insight from volatiles in fluid inclusions

Research Article| December 01, 2013 Does gold in orogenic deposits come from pyrite in deeply buried carbon-rich sediments?: Insight from volatiles in fluid inclusions Damien Gaboury Damien Gaboury Laboratoire de Métallogénie Expérimentale et Quantitative (LAMEQ), Université du Québec à Chicoutimi (UQAC), 555 Boulevard de l'Université, Chicoutimi, Québec G7H 2B1, Canada Search for other works by this author on: GSW Google Scholar Author and Article Information Damien Gaboury Laboratoire de Métallogénie Expérimentale et Quantitative (LAMEQ), Université du Québec à Chicoutimi (UQAC), 555 Boulevard de l'Université, Chicoutimi, Québec G7H 2B1, Canada Publisher: Geological Society of America Received: 30 May 2013 Revision Received: 11 Aug 2013 Accepted: 29 Aug 2013 First Online: 09 Mar 2017 Online ISSN: 1943-2682 Print ISSN: 0091-7613 © 2013 Geological Society of America Geology (2013) 41 (12): 1207–1210. https://doi.org/10.1130/G34788.1 Article history Received: 30 May 2013 Revision Received: 11 Aug 2013 Accepted: 29 Aug 2013 First Online: 09 Mar 2017 Cite View This Citation Add to Citation Manager Share Icon Share Facebook Twitter LinkedIn Email Permissions Search Site Citation Damien Gaboury; Does gold in orogenic deposits come from pyrite in deeply buried carbon-rich sediments?: Insight from volatiles in fluid inclusions. Geology 2013;; 41 (12): 1207–1210. doi: https://doi.org/10.1130/G34788.1 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 origin of volatiles in fluid inclusions was reviewed for testing the involvement at depth of carbonaceous-pyritic sedimentary rocks as the source for orogenic gold mineralization. Fluid inclusions from selected deposits were analyzed by solid-probe mass spectrometry. Fluids are mostly aqueous-carbonic, with variable amounts of N2, CH4, C2H6, Ar, H2S, H2 and He. For fluids with CH4 and C2H6, their ratios (C1/C2) range from 2.6 to 25.5, indicating that C2H6 is sourced from thermally degraded organic matter. Proportions of CO2, CH4, C2H6 and H2 are highly variable and can be explained by hydrothermal reactions where C2H6 is degraded to CO2 by water consumption. Such reactions may account for the problematic CO2-rich, H2O-poor fluids associated with some of the richest gold districts. Conditions needed for C2H6 degradation are also fundamental for forming gold deposits, such as HS–-enriched fluids for carrying gold and local weakly oxidizing conditions for promoting gold precipitation. The C2H6 content is recorded in fluids from Mesoarchean to Cretaceous gold deposits, providing support for a general model where fluids and gold were sourced from deeply buried, carbon-rich, and pyrite-gold–bearing sedimentary rocks. You do not have access to this content, please speak to your institutional administrator if you feel you should have access.