Pb-Zn ore deposits of the northern Caledonides: Products of continental-scale fluid mixing and tectonic expulsion during continental collision

Abstract

Research Article| November 01, 1988 Pb-Zn ore deposits of the northern Caledonides: Products of continental-scale fluid mixing and tectonic expulsion during continental collision M. J. Duane; M. J. Duane 1Bernard Price Institute for Geophysical Research, University of the Witwatersrand, Johannesburg 2050, South Africa Search for other works by this author on: GSW Google Scholar M. J. de Wit M. J. de Wit 1Bernard Price Institute for Geophysical Research, University of the Witwatersrand, Johannesburg 2050, South Africa Search for other works by this author on: GSW Google Scholar Author and Article Information M. J. Duane 1Bernard Price Institute for Geophysical Research, University of the Witwatersrand, Johannesburg 2050, South Africa M. J. de Wit 1Bernard Price Institute for Geophysical Research, University of the Witwatersrand, Johannesburg 2050, South Africa Publisher: Geological Society of America First Online: 02 Jun 2017 Online ISSN: 1943-2682 Print ISSN: 0091-7613 Geological Society of America Geology (1988) 16 (11): 999–1002. https://doi.org/10.1130/0091-7613(1988)016<0999:PZODOT>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 M. J. Duane, M. J. de Wit; Pb-Zn ore deposits of the northern Caledonides: Products of continental-scale fluid mixing and tectonic expulsion during continental collision. Geology 1988;; 16 (11): 999–1002. doi: https://doi.org/10.1130/0091-7613(1988)016<0999:PZODOT>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 Pb-Zn ore deposits within the northern Caledonides formed in compressional environments associated with major thrust sheets that were emplaced over foreland sediments during the final closure of the proto-Atlantic. Fluid migrations of saline brines are discussed, together with Pb-Pb isotope data that are consistent with collisioninduced (Laurentia-Baltica-Gondwana) tectonic plumbing systems through which ore fluids were driven to distant structural sites. Pb- isotope data from widely separated ore deposits across the orogen fall on a Pb-Pb linear array equivalent to a 2.05 Ga isochron; μvalues (238U/204Pb) increase from the central parts of the orogen toward its forelands. The array is interpreted as a Pb mixing line for averaged basement (3.8-0.6 Ga) and juvenile Paleozoic mantle Pb within the Caledonian orogen. Continued convergence and thrusting during the closing of the proto-Atlantic activated fluids within the sedimentary column and forced the escape and focusing of ore-bearing brines along horizontal and vertical decollements. Toward the forelands, the fluids interacted increasingly with older basement or sediments derived thereof. The process may have applications in deciphering collisional events and tectonic-fluid transport directions within older orogens. 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.