The role of continental lithosphere metasomes in the production of HIMU-like magmatism on the northeast African and Arabian plates

Research Article| May 01, 2014 The role of continental lithosphere metasomes in the production of HIMU-like magmatism on the northeast African and Arabian plates Tyrone O. Rooney; Tyrone O. Rooney * 1Department of Geological Sciences, Michigan State University, East Lansing, Michigan 48824, USA *E-mail: rooneyt@msu.edu. Search for other works by this author on: GSW Google Scholar Wendy R. Nelson; Wendy R. Nelson 2Department of Earth and Atmospheric Sciences, University of Houston, Houston, Texas 77204, USA Search for other works by this author on: GSW Google Scholar Laure Dosso; Laure Dosso 3Centre National de la Recherche Scientifique, UMR 6538, Domaines Océaniques, 29280 Plouzané, France Search for other works by this author on: GSW Google Scholar Tanya Furman; Tanya Furman 4Department of Geosciences, Pennsylvania State University, University Park, Pennsylvania 16802, USA Search for other works by this author on: GSW Google Scholar Barry Hanan Barry Hanan 5Department of Geological Sciences, San Diego State University, San Diego, California 92182-1020, USA Search for other works by this author on: GSW Google Scholar Geology (2014) 42 (5): 419–422. https://doi.org/10.1130/G35216.1 Article history received: 18 Oct 2013 rev-recd: 10 Feb 2014 accepted: 23 Feb 2014 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 Tyrone O. Rooney, Wendy R. Nelson, Laure Dosso, Tanya Furman, Barry Hanan; The role of continental lithosphere metasomes in the production of HIMU-like magmatism on the northeast African and Arabian plates. Geology 2014;; 42 (5): 419–422. doi: https://doi.org/10.1130/G35216.1 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 Intraplate alkaline lavas typically exhibit isotopic characteristics that require a source with long-term isolation from the convecting asthenosphere, such as in the sub-continental lithosphere mantle or a mantle boundary layer. Melting of metasomatically enriched domains, or metasomes, within the lithospheric mantle provides a viable mechanism for generating the geochemical characteristics of intraplate alkaline basalts. The origins and distribution of these metasomes have been attributed to recent enrichment of the lithosphere by a mantle plume or ancient events that occurred during the early evolution of the sub-continental lithosphere mantle. Here, we present a geochemical study of Ethiopian Miocene intraplate alkaline lavas: melts of a lithospheric mantle that was enriched metasomatically during lithospheric stabilization and by recent plume-lithosphere interaction. We find that these lavas have geochemical characteristics consistent with melting of an amphibole-bearing lithospheric-mantle metasome. New Pb and Hf isotope data for these lavas require a HIMU-like source component, similar to other alkaline lavas erupted through the Horn of Africa, Sudan, and Egypt, and adjacent Arabian plate lithospheres. The isotopic characteristics of this component are distinct from the Afar plume mantle source and instead are consistent with the long-term evolution of a lithospheric metasome created during a Neoproterozoic subduction event associated with the Pan-African orogeny. The widespread distribution of easily fusible lithospheric metasomes within the continental lithosphere mantle may facilitate magma generation without the need for substantial lithospheric thinning or elevated mantle potential temperatures. Mantle heterogeneity of this nature has implications for the source origin of HIMU magmas associated with continental lithosphere. You do not have access to this content, please speak to your institutional administrator if you feel you should have access.