SIMS chlorine isotope analyses in melt inclusions from arc settings
Manzini Mélina, Bouvier Anne-Sophie, Barnes Jaime, Bonifacie Magali, Rose-Koga Estelle , Ulmer Peter, Métrich Nicole, Bardoux Gérard, Williams Jeffrey, Layne Graham, Straub Susanne, Baumgartner Lukas, John Timm. 2017-01-20. .
ARTICLE, (2017-01-20 ) - PUBLISHEDVERSION - English (en-GB)
OPENACCESS -
info:eu-repo/semantics/OpenAccess.
Audience : OTHER
HAL CCSD, Elsevier
Sujet
Chlorine stable isotopes, SIMS, Olivine-hosted melt inclusions, Volcanic arcs, [SDU.STU.GC]Sciences of the Universe [physics]/Earth Sciences/Geochemistry
Domaines
Géologie, Sciences de la Terre
Description
International audience The relative contribution of volatiles from altered oceanic crust, serpentinized mantle, and subducted sediments on the composition of primary arc magmas is poorly constrained. We measured the chlorine stable isotope composition in olivine-hosted melt inclusions in order to provide a first order constraint on the δ37Cl values of primary magmas, since melt inclusions are not or only little affected by near surface processes. Chlorine isotope analyses were obtained with a CAMECA IMS 1280-HR at the University of Lausanne. A series of six Cl-bearing glass standards with δ37Cl values of − 1.1 to + 1.7‰, SiO2 between 50 and 76 wt% and Cl concentration between 0.15 and 3.25 wt% were used for calibration. We determined that SiO2, Al2O3 and K2O in glasses are primarily responsible for the observed variations in instrumental mass fractionation.We obtained a δ37Cl reproducibility on the standard glasses typically better than 0.3‰ (2SD) and a total uncertainty, corresponding to the propagated error of SIMS and Pyro-IRMS uncertainty, of 0.4‰ (2SD). Melt inclusions from Lesser Antilles, Vanuatu and Aeolian arcs display ranges of δ37Cl values from − 1.9 to + 0.6‰, − 1.7 to + 0.4‰ and − 3.4 to − 1.4‰ respectively. Combined with Cl/K2O ratios, these data suggest that Cl addition mainly originates from serpentinites (lithospheric serpentinites or serpentinized mantle wedge) in the Lesser Antilles and Vanuatu arcs. In contrast, Cl added to the mantle wedge beneath the Aeolian Islands may record a higher proportion of fluids derived from the subducting sediments. The observed differences of δ37Cl values in melt inclusions from the Lesser Antilles and Vanuatu arcs and the Aeolian Islands may directly reflect the different subduction geometries present.
Auteurs
Manzini, Mélina, Bouvier, Anne-Sophie, Barnes, Jaime, Bonifacie, Magali, Rose-Koga, Estelle, , Ulmer, Peter, Métrich, Nicole, Bardoux, Gérard, Williams, Jeffrey, Layne, Graham, Straub, Susanne, Baumgartner, Lukas, John, Timm
Contributeurs
Institute of Earth Sciences [Lausanne] ; University of Lausanne (UNIL), Department of Geological Sciences [Austin] ; Jackson School of Geosciences (JSG) ; University of Texas at Austin [Austin]-University of Texas at Austin [Austin], Institut de Physique du Globe de Paris (IPGP) ; Institut national des sciences de l'Univers (INSU - CNRS)-IPG PARIS-Université Paris Diderot - Paris 7 (UPD7)-Université de La Réunion (UR)-Centre National de la Recherche Scientifique (CNRS), Observatoire Volcanologique et Sismologique de Guadeloupe (OVSG) ; Institut de Physique du Globe de Paris, Laboratoire Magmas et Volcans (LMV) ; Institut national des sciences de l'Univers (INSU - CNRS)-Université Jean Monnet [Saint-Étienne] (UJM)-Institut de Recherche pour le Développement et la société-Université Clermont Auvergne [2017-2020] (UCA [2017-2020])-Centre National de la Recherche Scientifique (CNRS)-Observatoire de Physique du Globe de Clermont-Ferrand (OPGC) ; Institut national des sciences de l'Univers (INSU - CNRS)-Université Clermont Auvergne [2017-2020] (UCA [2017-2020])-Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Clermont Auvergne [2017-2020] (UCA [2017-2020])-Centre National de la Recherche Scientifique (CNRS), Institute of Geochemistry and Petrology [ETH Zürich] ; Department of Earth Sciences [Swiss Federal Institute of Technology - ETH Zürich] (D-ERDW) ; Eidgenössische Technische Hochschule - Swiss Federal Institute of Technology [Zürich] (ETH Zürich)- Eidgenössische Technische Hochschule - Swiss Federal Institute of Technology [Zürich] (ETH Zürich), Department of Earth and Planetary Sciences [Albuquerque] (EPS) ; The University of New Mexico [Albuquerque], Department of Earth Sciences [St. John's] ; Memorial University of Newfoundland = Université Memorial de Terre-Neuve [St. John's, Canada] (MUN), Lamont-Doherty Earth Observatory (LDEO) ; Columbia University [New York], Institut für Geologische Wissenschaften ; Freie Universität Berlin
Sources
ISSN: 0009-2541, Chemical Geology, Chemical Geology, Elsevier, 2017, 449, pp.112-122. ⟨10.1016/j.chemgeo.2016.12.002⟩
