气候变化领域集成服务门户(CCPortal): Silicate weathering in anoxic marine sediment as a requirement for authigenic carbonate burial

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DOI	10.1016/j.earscirev.2019.102960
	Silicate weathering in anoxic marine sediment as a requirement for authigenic carbonate burial
	Torres M.E.; Hong W.-L.; Solomon E.A.; Milliken K.; Kim J.-H.; Sample J.C.; Teichert B.M.A.; Wallmann K.
发表日期	2020
ISSN	00128252
卷号	200
英文摘要	We emphasize the importance of marine silicate weathering (MSiW) reactions in anoxic sediment as fundamental in generating alkalinity and cations needed for carbonate precipitation and preservation along continental margins. We use a model that couples thermodynamics with aqueous geochemistry to show that the CO2 released during methanogenesis results in a drop in pH to 6.0; unless these protons are buffered by MSiW, carbonate minerals will dissolve. We present data from two regions: the India passive margin and the active subduction zone off Japan, where ash and/or rivers supply the reactive silicate phase, as reflected in strontium isotope data. Offshore India and Korea, alteration of continent-derived silicates results in pore water enriched in radiogenic 87Sr, with 87Sr/86Sr ratios as high as 0.7095 and 0.7104, respectively. Off Japan, strontium in pore water influenced by ash alteration is depleted in 87Sr, with 87Sr/86Sr as low as 0.7065. Carbonate minerals formed by alkalinity and cations generated through MSiW carry these strontium isotopic signals, and are typically dolomite, siderite, and Fe-rich calcite. These contrast with the aragonite and high-magnesium calcite that form during anaerobic oxidation of methane and incorporate the coeval seawater 87Sr/86Sr signal. We show that MSiW is necessary for authigenic carbonate formation and preservation along continental margins, which remove carbon from Earth's surface at rates previously estimated to be at least 1012 mol yr−1. In addition, these authigenic carbonates are of relevance to studies of the deep biosphere, fluid flow, seismogenesis, slope stability, and reservoir characteristics. © 2019
关键词	Alkalinity Authigenic carbonate Carbon cycling Organogenic dolomite Silicate weathering
英文关键词	alkalinity; authigenesis; burial diagenesis; carbon dioxide; carbonate; chemical weathering; dolomite; marine sediment; passive margin; silicate; slope stability; subduction zone; India; Japan; Korea
语种	英语
来源期刊	Earth Science Reviews
文献类型	期刊论文
条目标识符	http://gcip.llas.ac.cn/handle/2XKMVOVA/203908
作者单位	College of Earth, Ocean and Atmospheric Science, Oregon State University, Corvallis, OR 97331, United States; Geological Survey of Norway, Trondheim, Norway; School of Oceanography, University of Washington, Seattle, WA 98195, United States; Bureau of Economic Geology, University of Texas at Austin, Austin, TX 78713, United States; Petroleum and Marine Research Division, Korea Institute of Geoscience and Mineral Resources, Daejeon, South Korea; School of Earth and Sustainability, Northern Arizona University, Flagstaff, AZ 86011, United States; Geologisch-Paläontologisches Institut, Wilhelms-Universität Münster, Corrensstr. 24, Münster, 48149, Germany; IFM-GEOMAR Leibniz Institute of Marine Sciences, Wischhofstrasse 1-3, Kiel, 24148, Germany
推荐引用方式 GB/T 7714	Torres M.E.,Hong W.-L.,Solomon E.A.,et al. Silicate weathering in anoxic marine sediment as a requirement for authigenic carbonate burial[J],2020,200.
APA	Torres M.E..,Hong W.-L..,Solomon E.A..,Milliken K..,Kim J.-H..,...&Wallmann K..(2020).Silicate weathering in anoxic marine sediment as a requirement for authigenic carbonate burial.Earth Science Reviews,200.
MLA	Torres M.E.,et al."Silicate weathering in anoxic marine sediment as a requirement for authigenic carbonate burial".Earth Science Reviews 200(2020).