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DOI	10.1038/s41561-019-0471-y
	Release of oxidizing fluids in subduction zones recorded by iron isotope zonation in garnet
	Gerrits A.R.; Inglis E.C.; Dragovic B.; Starr P.G.; Baxter E.F.; Burton K.W.
发表日期	2019
ISSN	17520894
卷号	12 期号:12
英文摘要	Subduction zones are key regions of chemical and mass transfer between the Earth’s surface and mantle. During subduction, oxidized material is carried into the mantle and large amounts of water are released due to the breakdown of hydrous minerals such as lawsonite. Dehydration accompanied by the release of oxidizing species may play a key role in controlling redox changes in the subducting slab and overlying mantle wedge. Here we present measurements of oxygen fugacity, using garnet–epidote oxybarometry, together with analyses of the stable iron isotope composition of zoned garnets from Sifnos, Greece. We find that the garnet interiors grew under relatively oxidized conditions whereas garnet rims record more reduced conditions. Garnet δ56Fe increases from core to rim as the system becomes more reduced. Thermodynamic analysis shows that this change from relatively oxidized to more reduced conditions occurred during lawsonite dehydration. We conclude that the garnets maintain a record of progressive dehydration and that the residual mineral assemblages within the slab became more reduced during progressive subduction-zone dehydration. This is consistent with the hypothesis that lawsonite dehydration accompanied by the release of oxidizing species, such as sulfate, plays an important and measurable role in the global redox budget and contributes to sub-arc mantle oxidation in subduction zones. © 2019, The Author(s), under exclusive licence to Springer Nature Limited.
语种	英语
scopus关键词	dehydration; garnet; isotopic composition; lawsonite; mantle; oxidation; subduction zone; thermodynamics; Cyclades; Greece; Milos [Southern Aegean]; Sifnos; Southern Aegean
来源期刊	Nature Geoscience
文献类型	期刊论文
条目标识符	http://gcip.llas.ac.cn/handle/2XKMVOVA/124559
作者单位	Department of Earth and Environmental Sciences, Boston College, Chestnut Hill, MA, United States; Institut de Physique du Globe de Paris, Sorbonne Paris Cité, CNRS, Paris, France; School of the Earth, Ocean and Environment, University of South Carolina, Columbia, SC, United States; Department of Earth Sciences, Durham University, Science Labs, Durham, United Kingdom
推荐引用方式 GB/T 7714	Gerrits A.R.,Inglis E.C.,Dragovic B.,et al. Release of oxidizing fluids in subduction zones recorded by iron isotope zonation in garnet[J],2019,12(12).
APA	Gerrits A.R.,Inglis E.C.,Dragovic B.,Starr P.G.,Baxter E.F.,&Burton K.W..(2019).Release of oxidizing fluids in subduction zones recorded by iron isotope zonation in garnet.Nature Geoscience,12(12).
MLA	Gerrits A.R.,et al."Release of oxidizing fluids in subduction zones recorded by iron isotope zonation in garnet".Nature Geoscience 12.12(2019).