Dataset Information

Serpentine alteration as source of high dissolved silicon and elevated ?³⁰Si values to the marine Si cycle.

ABSTRACT: Serpentine alteration is recognized as an important process for element cycling, however, related silicon fluxes are unknown. Pore fluids from serpentinite seamounts sampled in the Mariana forearc region during IODP Expedition 366 were investigated for their Si, B, and Sr isotope signatures (?³⁰Si, ?¹¹B, and ⁸⁷Sr/⁸⁶Sr, respectively) to study serpentinization in the mantle wedge and shallow serpentine alteration to authigenic clays by seawater. While serpentinization in the mantle wedge caused no significant Si isotope fractionation, implying closed system conditions, serpentine alteration by seawater led to the formation of authigenic phyllosilicates, causing the highest natural fluid ?³⁰Si values measured to date (up to +5.2?±?0.2‰). Here we show that seafloor alteration of serpentinites is a source of Si to the ocean with extremely high fluid ?³⁰Si values, which can explain anomalies in the marine Si budget like in the Cascadia Basin and which has to be considered in future investigations of the global marine Si cycle.

SUBMITTER: Geilert S

PROVIDER: S-EPMC7550359 | biostudies-literature | 2020 Oct

REPOSITORIES: biostudies-literature

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Serpentine alteration as source of high dissolved silicon and elevated δ30Si values to the marine Si cycle.

Geilert Sonja S Grasse Patricia P Wallmann Klaus K Liebetrau Volker V Menzies Catriona D CD

Nature communications 20201012 1

Serpentine alteration is recognized as an important process for element cycling, however, related silicon fluxes are unknown. Pore fluids from serpentinite seamounts sampled in the Mariana forearc region during IODP Expedition 366 were investigated for their Si, B, and Sr isotope signatures (δ30Si, δ11B, and 87Sr/86Sr, respectively) to study serpentinization in the mantle wedge and shallow serpentine alteration to authigenic clays by seawater. While se ...[more]

PMID: 33046703

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Dataset Information

Serpentine alteration as source of high dissolved silicon and elevated ?³⁰Si values to the marine Si cycle.

Publications

Serpentine alteration as source of high dissolved silicon and elevated δ<sup>30</sup>Si values to the marine Si cycle.

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Dataset Information

Serpentine alteration as source of high dissolved silicon and elevated ?30Si values to the marine Si cycle.

Publications

Serpentine alteration as source of high dissolved silicon and elevated δ<sup>30</sup>Si values to the marine Si cycle.

Similar Datasets

OmicsDI is part of the ELIXIR infrastructure

Serpentine alteration as source of high dissolved silicon and elevated ?³⁰Si values to the marine Si cycle.