Mantle-drip magmatism beneath the Altiplano-Puna plateau, central Andes

Abstract

Research Article| August 01, 2013 Mantle-drip magmatism beneath the Altiplano-Puna plateau, central Andes M.N. Ducea; M.N. Ducea 1Universitatea Bucuresti, Facultatea de Geologie-Geofizica, Bucharest 010041, Romania2University of Arizona, Department of Geosciences, Tucson, Arizona 85721, USA Search for other works by this author on: GSW Google Scholar A.C. Seclaman; A.C. Seclaman 1Universitatea Bucuresti, Facultatea de Geologie-Geofizica, Bucharest 010041, Romania2University of Arizona, Department of Geosciences, Tucson, Arizona 85721, USA Search for other works by this author on: GSW Google Scholar K.E. Murray; K.E. Murray 2University of Arizona, Department of Geosciences, Tucson, Arizona 85721, USA Search for other works by this author on: GSW Google Scholar D. Jianu; D. Jianu 1Universitatea Bucuresti, Facultatea de Geologie-Geofizica, Bucharest 010041, Romania Search for other works by this author on: GSW Google Scholar L.M. Schoenbohm L.M. Schoenbohm 3University of Toronto, Department of Geology, Toronto, ON M5S 3B1, Canada Search for other works by this author on: GSW Google Scholar Author and Article Information M.N. Ducea 1Universitatea Bucuresti, Facultatea de Geologie-Geofizica, Bucharest 010041, Romania2University of Arizona, Department of Geosciences, Tucson, Arizona 85721, USA A.C. Seclaman 1Universitatea Bucuresti, Facultatea de Geologie-Geofizica, Bucharest 010041, Romania2University of Arizona, Department of Geosciences, Tucson, Arizona 85721, USA K.E. Murray 2University of Arizona, Department of Geosciences, Tucson, Arizona 85721, USA D. Jianu 1Universitatea Bucuresti, Facultatea de Geologie-Geofizica, Bucharest 010041, Romania L.M. Schoenbohm 3University of Toronto, Department of Geology, Toronto, ON M5S 3B1, Canada Publisher: Geological Society of America Received: 21 Feb 2013 Revision Received: 02 Apr 2013 Accepted: 08 Apr 2013 First Online: 09 Mar 2017 Online ISSN: 1943-2682 Print ISSN: 0091-7613 © 2013 Geological Society of America Geology (2013) 41 (8): 915–918. https://doi.org/10.1130/G34509.1 Article history Received: 21 Feb 2013 Revision Received: 02 Apr 2013 Accepted: 08 Apr 2013 First Online: 09 Mar 2017 Cite View This Citation Add to Citation Manager Share Icon Share Facebook Twitter LinkedIn Email Permissions Search Site Citation M.N. Ducea, A.C. Seclaman, K.E. Murray, D. Jianu, L.M. Schoenbohm; Mantle-drip magmatism beneath the Altiplano-Puna plateau, central Andes. Geology 2013;; 41 (8): 915–918. doi: https://doi.org/10.1130/G34509.1 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 Convective removal of continental lithospheric roots has been postulated to be the primary mechanism of recycling lithospheric mass into the asthenosphere under large plateaux such as the Altiplano-Puna in the central Andes. Convective instabilities are especially likely to develop where there is extensive intermediate arc-like magmatism in the upper plate, as the residual masses complementing these magmatic products are typically denser than the underlying mantle. Mafic volcanic rocks erupted on the central Andean Altiplano-Puna plateau during the past 25 m.y. contain evidence of this process. Here we use equilibration temperatures, age data, and geochemical constraints—primarily based on transition metals—to show that the most important source materials by mass for this mantle-derived magmatism are pyroxenites from the lower parts of the lithosphere, with only minor contributions from mantle peridotite. Pyroxenites are denser than typical upper mantle whether they are garnet bearing or not, and are therefore likely to contribute to destabilizing parts of the continental lithosphere. The pattern of melting is consistent with the process of foundering/dripping of small-scale (<50 km diameter) density anomalies in the lithosphere, where mafic volcanic fields on the plateau represent the manifestations of individual drips. You do not have access to this content, please speak to your institutional administrator if you feel you should have access.