F, Cl and S input via serpentinite in subduction zones; implications for the nature of the fluid released at depth

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doi: 10.1111/ter.12074
Author(s): Debret, Baptiste; Koga, Kenneth T.; Nicollet, Christian; Andreani, Muriel; Schwartz, Stéphane
Author Affiliation(s): Primary:
Clermont Universite-Universite Blaise Pascal, Clermont-Ferrand, France
Other:
Universite Lyon I, France
Universite Grenoble I, France
Volume Title: Terra Nova
Source: Terra Nova, 26(2), p.96-101. Publisher: Wiley-Blackwell, Oxford, United Kingdom. ISSN: 0954-4879
Note: In English. 36 refs.; illus., incl. sketch map
Summary: The abundances of F, Cl and S in arc magmas are systematically higher than in other mantle-derived magmas, suggesting that these elements are added from the slab along with H2O. We present ion probe microanalyses of F, Cl and S in serpentine minerals that represent the P-T evolution of the oceanic lithosphere, from its serpentinization at the ridge, to its dehydration at around 100 km depth during subduction. F, Cl and S are incorporated early into serpentine during its formation at mid-ocean ridges, and serpentinized lithosphere then carries these elements to subduction zones. More than 50% of the F, Cl and S are removed from serpentine during the prograde metamorphic lizardite/antigorite transition. Due to the low solubility of F in water, and to the low amount of water released during this phase transition, the fluids mobilizing these elements must be dominated by SOX rather than H2O. Abstract Copyright (2014), John Wiley & Sons, Ltd.
Year of Publication: 2014
Research Program: ODP Ocean Drilling Program
Key Words: 05 Petrology, Igneous and Metamorphic; Alps; Atlantic Ocean; Chlorine; Corsica; Europe; Facies; Fluorine; France; Greenschist facies; Halogens; Ion probe data; Leg 153; Ligurian Sea; Lithosphere; Magmas; Mass spectra; Mediterranean Sea; Metaigneous rocks; Metamorphic rocks; Metasomatic rocks; Metasomatism; Mid-Atlantic Ridge; Mineral composition; Monte Maggiore; North Atlantic; ODP Site 920; Ocean Drilling Program; Oceanic lithosphere; Ophiolite; P-T conditions; Serpentinite; Serpentinization; Slabs; Spectra; Subduction zones; Sulfur; West Mediterranean; Western Alps; Western Europe
Coordinates: N232018 N232019 W0450102 W0450103
Record ID: 2014038926
Copyright Information: GeoRef, Copyright 2019 American Geosciences Institute. Reference includes data from John Wiley & Sons, Chichester, United Kingdom