The Dehshir ophiolite (central Iran): Geochemical constraints on the origin and evolution of the Inner Zagros ophiolite belt

Research Article| September 01, 2010 The Dehshir ophiolite (central Iran): Geochemical constraints on the origin and evolution of the Inner Zagros ophiolite belt H. Shafaii Moghadam; H. Shafaii Moghadam † 1School of Earth Sciences, Damghan University of Basic Sciences, Damghan, Iran †E-mail: hadishaffaii@dubs.ac.ir Search for other works by this author on: GSW Google Scholar Robert J. Stern; Robert J. Stern 2Geosciences Department, University of Texas at Dallas, Richardson, Texas 75083-0688, USA Search for other works by this author on: GSW Google Scholar M. Rahgoshay M. Rahgoshay 3Faculty of Earth Sciences, Shahid Beheshti University, Tehran, Iran Search for other works by this author on: GSW Google Scholar Author and Article Information H. Shafaii Moghadam † 1School of Earth Sciences, Damghan University of Basic Sciences, Damghan, Iran Robert J. Stern 2Geosciences Department, University of Texas at Dallas, Richardson, Texas 75083-0688, USA M. Rahgoshay 3Faculty of Earth Sciences, Shahid Beheshti University, Tehran, Iran †E-mail: hadishaffaii@dubs.ac.ir Publisher: Geological Society of America Received: 05 Apr 2009 Revision Received: 23 Aug 2009 Accepted: 24 Aug 2009 First Online: 08 Mar 2017 Online ISSN: 1943-2674 Print ISSN: 0016-7606 © 2010 Geological Society of America GSA Bulletin (2010) 122 (9-10): 1516–1547. https://doi.org/10.1130/B30066.1 Article history Received: 05 Apr 2009 Revision Received: 23 Aug 2009 Accepted: 24 Aug 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 H. Shafaii Moghadam, Robert J. Stern, M. Rahgoshay; The Dehshir ophiolite (central Iran): Geochemical constraints on the origin and evolution of the Inner Zagros ophiolite belt. GSA Bulletin 2010;; 122 (9-10): 1516–1547. doi: https://doi.org/10.1130/B30066.1 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 Late Cretaceous Dehshir ophiolite is an important element within the Inner Zagros (Nain-Baft) ophiolite belt and contains all components of a complete "Penrose ophiolite," including tectonized harzburgites, gabbros, sheeted dike complexes, pillowed basalts, and rare ultramafic-mafic cumulates. The cumulate rocks of this ophiolite are composed of plagioclase lherzolite, clinopyroxenite, leucogabbro, and pegmatite gabbro. All the massifs in the Inner Zagros ophiolite belt are overlain by Turonian-Maastrichtian pelagic limestones (93.5–65.5 Ma). Clinopyroxene compositions of Dehshir mafic rocks are similar to those of both boninites and island-arc tholeiites. Nearly all spinels from the inner ophiolite belt are similar to those of highly depleted harzburgites from intra-oceanic forearcs, although some Dehshir harzburgite spinels plot within the field for abyssal (mid-ocean-ridge basalt) peridotites. All components of the Dehshir and other ophiolites of this belt show strong suprasubduction-zone affinities, from harzburgitic mantle to ophiolitic lavas. Volcanic rocks have a mixture of dominantly arc-like (island-arc tholeiite, boninite, and calc-alkaline) and subordinate mid-ocean-ridge basalt–like compositional features, usually with mid-ocean-ridge basalt–like rocks at the base and arc-like rocks at the top. Our data for the Dehshir ophiolite and the similarity of these results to those for Iranian inner and outer belt ophiolites compel the conclusion that a geographically long, broad, and continuous tract of forearc lithosphere was created at about the same time during the earliest stages of subduction along the southern margin of Eurasia in Late Cretaceous time. You do not have access to this content, please speak to your institutional administrator if you feel you should have access.