Nb-depleted andesites from the Pacific-Antarctic Rise as analogs for early continental crust

Abstract

Research Article| December 01, 2005 Nb-depleted andesites from the Pacific-Antarctic Rise as analogs for early continental crust Karsten M. Haase; Karsten M. Haase 1Institut für Geowissenschaften der Christian-Albrechts-Universität zu Kiel, Olshausenstrasse 40, D-24098 Kiel, Germany Search for other works by this author on: GSW Google Scholar Nicole A. Stroncik; Nicole A. Stroncik 1Institut für Geowissenschaften der Christian-Albrechts-Universität zu Kiel, Olshausenstrasse 40, D-24098 Kiel, Germany Search for other works by this author on: GSW Google Scholar Roger Hékinian; Roger Hékinian 1Institut für Geowissenschaften der Christian-Albrechts-Universität zu Kiel, Olshausenstrasse 40, D-24098 Kiel, Germany Search for other works by this author on: GSW Google Scholar Peter Stoffers Peter Stoffers 1Institut für Geowissenschaften der Christian-Albrechts-Universität zu Kiel, Olshausenstrasse 40, D-24098 Kiel, Germany Search for other works by this author on: GSW Google Scholar Geology (2005) 33 (12): 921–924. https://doi.org/10.1130/G21899.1 Article history received: 26 May 2005 rev-recd: 04 Jul 2005 accepted: 07 Jul 2005 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 Karsten M. Haase, Nicole A. Stroncik, Roger Hékinian, Peter Stoffers; Nb-depleted andesites from the Pacific-Antarctic Rise as analogs for early continental crust. Geology 2005;; 33 (12): 921–924. doi: https://doi.org/10.1130/G21899.1 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 Sampling of the Pacific-Antarctic Rise close to the Foundation hotspot in the South Pacific reveals that silicic lavas erupt together with basalts on a 130-km-long part of this mid-oceanic ridge, representing the most extensive occurrence of andesites on the submarine spreading system. Most of these tholeiitic andesites and dacites have negative Nb and Ta anomalies, a signature that has so far been attributed only to subduction-related magmas and the continental crust. The silicic lavas formed by fractional crystallization from basalts and assimilation of melts from hydrothermally altered amphibolite in the oceanic crust. The presence of andesites with negative Nb and Ta anomalies on the Pacific-Antarctic Rise implies that such magmas are not restricted to subduction zones but can form at a plume-influenced mid-oceanic ridge. The andesites and dacites from the Pacific-Antarctic Rise may represent analogs to some Precambrian volcanic rocks and early continental crust. You do not have access to this content, please speak to your institutional administrator if you feel you should have access.