Eoarchean within-plate basalts from southwest Greenland

Abstract

Research Article| March 01, 2013 Eoarchean within-plate basalts from southwest Greenland F.E. Jenner; F.E. Jenner * 1Department of Terrestrial Magnetism, Carnegie Institution of Washington, 5241 Broad Branch Road Northwest, Washington, DC 20015, USA2Research School of Earth Sciences, The Australian National University, Canberra, ACT 0200, Australia *E-mail: fjenner@dtm.ciw.edu. Search for other works by this author on: GSW Google Scholar V.C. Bennett; V.C. Bennett 2Research School of Earth Sciences, The Australian National University, Canberra, ACT 0200, Australia Search for other works by this author on: GSW Google Scholar G. Yaxley; G. Yaxley 2Research School of Earth Sciences, The Australian National University, Canberra, ACT 0200, Australia Search for other works by this author on: GSW Google Scholar C.R.L. Friend; C.R.L. Friend 3Glendale, Tiddington, Oxon OX9 2LQ, UK Search for other works by this author on: GSW Google Scholar O. Nebel O. Nebel 2Research School of Earth Sciences, The Australian National University, Canberra, ACT 0200, Australia Search for other works by this author on: GSW Google Scholar Geology (2013) 41 (3): 327–330. https://doi.org/10.1130/G33787.1 Article history received: 25 Jun 2012 rev-recd: 20 Sep 2012 accepted: 25 Sep 2012 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 F.E. Jenner, V.C. Bennett, G. Yaxley, C.R.L. Friend, O. Nebel; Eoarchean within-plate basalts from southwest Greenland. Geology 2013;; 41 (3): 327–330. doi: https://doi.org/10.1130/G33787.1 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 The majority of >3 Ga metabasalts have chemical features, such as high field strength element (HFSE) depletions, that are characteristic of modern island-arc basalts. These compositions have been interpreted as evidence for subduction of oceanic crust early in Earth’s history. Alternatively, the apparent absence of Archean mafic rocks with mid-oceanic ridge basalt (MORB) and ocean island basalt (OIB) compositions and the ubiquitous occurrence of metabasalts with HFSE anomalies suggest that these chemical features may instead be a widespread characteristic of the Archean mantle related to early chemical differentiation and unrelated to modern-style recycling of crust. Here we present major- and trace-element data for a suite of metabasalts from Innersuartuut Island, southwest Greenland, which have a minimum age constraint of 3.75 Ga and are likely as old as ≥3.85 Ga. Samples from Innersuartuut show no evidence for crustal contamination or subduction-related magmatism, and have a petrogenesis comparable to modern OIB. The new data demonstrate that a compositional range for volcanic rocks comparable to that seen in the Phanerozoic existed in the Eoarchean. Therefore, rather than a global anomaly, subduction-related processes are the likely origin for the compositions of the most commonly preserved Archean mafic rocks with island-arc basalt characteristics. You do not have access to this content, please speak to your institutional administrator if you feel you should have access.