Devonian and Carboniferous arcs of the Oyu Tolgoi porphyry Cu-Au district, South Gobi region, Mongolia

Abstract

Research Article| January 01, 2011 Devonian and Carboniferous arcs of the Oyu Tolgoi porphyry Cu-Au district, South Gobi region, Mongolia Alan J. Wainwright; Alan J. Wainwright 1Mineral Deposit Research Unit, Department of Earth and Ocean Sciences, University of British Columbia, 6339 Stores Road, Vancouver, British Columbia V6T 1Z4, Canada Search for other works by this author on: GSW Google Scholar Richard M. Tosdal; Richard M. Tosdal † 1Mineral Deposit Research Unit, Department of Earth and Ocean Sciences, University of British Columbia, 6339 Stores Road, Vancouver, British Columbia V6T 1Z4, Canada †E-mail: rtosdal@gmail.com Search for other works by this author on: GSW Google Scholar Charles N. Forster; Charles N. Forster 24011 Pipeline Road, Blaine, Washington 98230, USA Search for other works by this author on: GSW Google Scholar Douglas J. Kirwin; Douglas J. Kirwin 3Ivanhoe Mines, 51/278 Muang Ake, Tambon lak 6, Amphoe Muang, Pathumtani, Bangkok 12000, Thailand Search for other works by this author on: GSW Google Scholar Peter D. Lewis; Peter D. Lewis § 415715 Mountainview Drive, Surrey, British Columbia V3S 0C6, Canada §Present address: El Dorado Gold, 1188-550 Burrard Street, Vancouver, British Columbia V6C 2B5, Canada Search for other works by this author on: GSW Google Scholar Joseph L. Wooden Joseph L. Wooden # 5U.S. Geological Survey, MS-901, Menlo Park, California 94025, USA #Present address: Department of Geological and Environmental Science, Stanford University, Stanford, California 94304, USA Search for other works by this author on: GSW Google Scholar Author and Article Information Alan J. Wainwright 1Mineral Deposit Research Unit, Department of Earth and Ocean Sciences, University of British Columbia, 6339 Stores Road, Vancouver, British Columbia V6T 1Z4, Canada Richard M. Tosdal † 1Mineral Deposit Research Unit, Department of Earth and Ocean Sciences, University of British Columbia, 6339 Stores Road, Vancouver, British Columbia V6T 1Z4, Canada Charles N. Forster 24011 Pipeline Road, Blaine, Washington 98230, USA Douglas J. Kirwin 3Ivanhoe Mines, 51/278 Muang Ake, Tambon lak 6, Amphoe Muang, Pathumtani, Bangkok 12000, Thailand Peter D. Lewis § 415715 Mountainview Drive, Surrey, British Columbia V3S 0C6, Canada Joseph L. Wooden # 5U.S. Geological Survey, MS-901, Menlo Park, California 94025, USA †E-mail: rtosdal@gmail.com §Present address: El Dorado Gold, 1188-550 Burrard Street, Vancouver, British Columbia V6C 2B5, Canada #Present address: Department of Geological and Environmental Science, Stanford University, Stanford, California 94304, USA Publisher: Geological Society of America Received: 27 Jul 2009 Revision Received: 14 Dec 2009 Accepted: 14 Dec 2009 First Online: 08 Mar 2017 Online ISSN: 1943-2674 Print ISSN: 0016-7606 © 2011 Geological Society of America GSA Bulletin (2011) 123 (1-2): 306–328. https://doi.org/10.1130/B30137.1 Article history Received: 27 Jul 2009 Revision Received: 14 Dec 2009 Accepted: 14 Dec 2009 First Online: 08 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 Alan J. Wainwright, Richard M. Tosdal, Charles N. Forster, Douglas J. Kirwin, Peter D. Lewis, Joseph L. Wooden; Devonian and Carboniferous arcs of the Oyu Tolgoi porphyry Cu-Au district, South Gobi region, Mongolia. GSA Bulletin 2011;; 123 (1-2): 306–328. doi: https://doi.org/10.1130/B30137.1 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 SocietyGSA Bulletin Search Advanced Search Abstract The Central Asian orogenic belt consists of microcontinental blocks and mobile belts positioned between the Siberian craton and the Tarim and North China cratons. Extending across Asia for 5000 km, the belt consists of terranes that decrease in age southward away from the Siberian craton. A time-stratigraphic-structural sequence for the rocks is critical to defining the tectonic evolution of the belt. In the Oyu Tolgoi area of the South Gobi Desert (Mongolia), Devonian and Carboniferous rocks record the construction of multiple arcs, formation of a giant porphyry Cu-Au system, exhumation, and polyphase deformation. The oldest rocks are basaltic volcanic and subvolcanic rocks of the Devonian Alagbayan Group intruded by Late Devonian quartz monzodiorite stocks and dikes, which host giant porphyry Cu-Au deposits. The rocks were exhumed, overlain by pyroclastic rocks, and then tectonically buried by marine mafic supracrustal rocks prior to the youngest Devonian granodiorite intrusions. The postmineral Carboniferous Gurvankharaat Group unconformably overlying the deformed terrane consists of effusive, pyroclastic, subvolcanic and volcaniclastic rocks, as well as sedimentary units. The supracrustal rocks underwent polyphase shortening after 330 Ma and prior to 290 Ma. Variations in stratigraphic sequences suggest that the region is underlain by a submarine arc that became emergent during the Upper Devonian and remained subaerial to shallow subaqueous through much of the Carboniferous. Xenocrystic zircons in igneous rocks suggest that the offshore arcs were sufficiently close to ancient crust to have interacted with detritus shed into marine basins, most likely from the Siberian craton and fringing early Paleozoic terranes. You do not have access to this content, please speak to your institutional administrator if you feel you should have access.