Magma chamber–scale liquid immiscibility in the Siberian Traps represented by melt pools in native iron

Abstract

Research Article| October 01, 2013 Magma chamber–scale liquid immiscibility in the Siberian Traps represented by melt pools in native iron Vadim S. Kamenetsky; Vadim S. Kamenetsky * 1ARC Centre of Excellence in Ore Deposits and School of Earth Sciences, University of Tasmania, Hobart, TAS 7001, Australia *E-mail: Dima.Kamenetsky@utas.edu.au. Search for other works by this author on: GSW Google Scholar Bernard Charlier; Bernard Charlier 2Institut für Mineralogie, Leibniz Universität Hannover, Callinstrasse 3, 30167 Hannover, Germany Search for other works by this author on: GSW Google Scholar Liudmila Zhitova; Liudmila Zhitova 3Novosibirsk State University, Novosibirsk 630090, Russia4V.S. Sobolev Institute of Geology and Mineralogy SB RAS, Novosibirsk 630090, Russia Search for other works by this author on: GSW Google Scholar Victor Sharygin; Victor Sharygin 3Novosibirsk State University, Novosibirsk 630090, Russia4V.S. Sobolev Institute of Geology and Mineralogy SB RAS, Novosibirsk 630090, Russia Search for other works by this author on: GSW Google Scholar Paul Davidson; Paul Davidson 1ARC Centre of Excellence in Ore Deposits and School of Earth Sciences, University of Tasmania, Hobart, TAS 7001, Australia Search for other works by this author on: GSW Google Scholar Sandrin Feig Sandrin Feig 5Central Science Laboratory, University of Tasmania, Hobart, TAS 7001, Australia Search for other works by this author on: GSW Google Scholar Author and Article Information Vadim S. Kamenetsky * 1ARC Centre of Excellence in Ore Deposits and School of Earth Sciences, University of Tasmania, Hobart, TAS 7001, Australia Bernard Charlier 2Institut für Mineralogie, Leibniz Universität Hannover, Callinstrasse 3, 30167 Hannover, Germany Liudmila Zhitova 3Novosibirsk State University, Novosibirsk 630090, Russia4V.S. Sobolev Institute of Geology and Mineralogy SB RAS, Novosibirsk 630090, Russia Victor Sharygin 3Novosibirsk State University, Novosibirsk 630090, Russia4V.S. Sobolev Institute of Geology and Mineralogy SB RAS, Novosibirsk 630090, Russia Paul Davidson 1ARC Centre of Excellence in Ore Deposits and School of Earth Sciences, University of Tasmania, Hobart, TAS 7001, Australia Sandrin Feig 5Central Science Laboratory, University of Tasmania, Hobart, TAS 7001, Australia *E-mail: Dima.Kamenetsky@utas.edu.au. Publisher: Geological Society of America Received: 10 Apr 2013 Revision Received: 30 May 2013 Accepted: 12 Jun 2013 First Online: 09 Mar 2017 Online ISSN: 1943-2682 Print ISSN: 0091-7613 © 2013 Geological Society of America Geology (2013) 41 (10): 1091–1094. https://doi.org/10.1130/G34638.1 Article history Received: 10 Apr 2013 Revision Received: 30 May 2013 Accepted: 12 Jun 2013 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 Vadim S. Kamenetsky, Bernard Charlier, Liudmila Zhitova, Victor Sharygin, Paul Davidson, Sandrin Feig; Magma chamber–scale liquid immiscibility in the Siberian Traps represented by melt pools in native iron. Geology 2013;; 41 (10): 1091–1094. doi: https://doi.org/10.1130/G34638.1 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 Magma unmixing (i.e., separation of a homogeneous silicate melt into two or more liquids) is responsible for sudden changes in the evolution of common melts, element fractionation, and potential formation of orthomagmatic ore deposits. Although immiscible phases are a common phenomenon in the mesostasis of many tholeiitic basalts, evidence of unmixing in intrusive rocks is more difficult to record because of the transient nature of immiscibility during decompression, cooling, and crystallization. In this paper, we document a clear case of liquid immiscibility in an intrusive body of tholeiitic gabbro in the Siberian large igneous province, using textures and compositions of millimeter-sized silicate melt pools in native iron. The native iron crystallized from a metallic iron liquid, which originated as disseminated globules during reduction of the basaltic magma upon interaction with coal-bearing sedimentary rocks in the Siberian craton. The silicate melts entrapped and armored by the native iron are composed of two types of globules that represent the aluminosilicate (60–77 wt% SiO2) and silica-poor, Fe-Ti-Ca-P–rich (in wt%: SiO2, 15–46; FeO, 15–22; TiO2, 2–7; CaO, 11–27; P2O5, 5–30) conjugate liquids. Different proportions and the correlated compositions of these globules in individual melt pools suggest a continuously evolving environment of magmatic immiscibility during magma cooling. These natural immiscible melts correspond extremely well to the conjugate liquids experimentally produced in common basaltic compositions at <1025 °C. Our results show that immiscibility can occur at large scale in magma chambers and can be instrumental in generating felsic magmas and Fe-Ti-Ca-P–rich melts in the continental igneous provinces. You do not have access to this content, please speak to your institutional administrator if you feel you should have access.