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Geochemical evidence for melange melting in global arcs.

ABSTRACT: In subduction zones, sediments and hydrothermally altered oceanic crust, which together form part of the subducting slab, contribute to the chemical composition of lavas erupted at the surface to form volcanic arcs. Transport of this material from the slab to the overlying mantle wedge is thought to involve discreet melts and fluids that are released from various portions of the slab. We use a meta-analysis of geochemical data from eight globally representative arcs to show that melts and fluids from individual slab components cannot be responsible for the formation of arc lavas. Instead, the data are compatible with models that first invoke physical mixing of slab components and the mantle wedge, widely referred to as high-pressure mélange, before arc magmas are generated.

SUBMITTER: Nielsen SG

PROVIDER: S-EPMC5384804 | biostudies-literature | 2017 Apr

REPOSITORIES: biostudies-literature

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Geochemical evidence for mélange melting in global arcs.

Nielsen Sune G SG Marschall Horst R HR

Science advances 20170407 4

In subduction zones, sediments and hydrothermally altered oceanic crust, which together form part of the subducting slab, contribute to the chemical composition of lavas erupted at the surface to form volcanic arcs. Transport of this material from the slab to the overlying mantle wedge is thought to involve discreet melts and fluids that are released from various portions of the slab. We use a meta-analysis of geochemical data from eight globally representative arcs to show that melts and fluids ...[more]

PMID: 28435882

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Geochemical evidence for melange melting in global arcs.

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Geochemical evidence for mélange melting in global arcs.

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