气候变化领域集成服务门户(CCPortal): Redox control on the tungsten isotope composition of seawater

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DOI	10.1073/pnas.2023544118
	Redox control on the tungsten isotope composition of seawater
	Kurzweil F.; Archer C.; Wille M.; Schoenberg R.; Münker C.; Dellwig O.
发表日期	2021
ISSN	00278424
卷号	118 期号:18
英文摘要	Free oxygen represents an essential basis for the evolution of complex life forms on a habitable Earth. The isotope composition of redox-sensitive trace elements such as tungsten (W) can possibly trace the earliest rise of oceanic oxygen in Earth's history. However, the impact of redox changes on the W isotope composition of seawater is still unknown. Here, we report highly variable W isotope compositions in the water column of a redox-stratified basin (δ186/184W between +0.347 and +0.810 ‰) that contrast with the homogenous W isotope composition of the open ocean (refined δ186/184W of +0.543 ± 0.046 ‰). Consistent with experimental studies, the preferential scavenging of isotopically light W by Mn-oxides increases the δ186/184W of surrounding seawater, whereas the redissolution of Mn-oxides causes decreasing seawater δ186/184W. Overall, the distinctly heavy stable W isotopic signature of open ocean seawater mirrors predominantly fully oxic conditions in modern oceans. We expect, however, that the redox evolution from anoxic to hypoxic and finally oxic marine conditions in early Earth's history would have continuously increased the seawater δ186/184W. Stable W isotope compositions of chemical sediments that potentially preserve changing seawater W isotope signatures might therefore reflect global changes in marine redox conditions. © 2021 National Academy of Sciences. All rights reserved.
英文关键词	Euxinic porewater; Mn-oxide; Paleoredox; Seawater; Stable tungsten isotopes
语种	英语
来源期刊	Proceedings of the National Academy of Sciences of the United States of America
文献类型	期刊论文
条目标识符	http://gcip.llas.ac.cn/handle/2XKMVOVA/179697
作者单位	Institut für Geologie und Mineralogie, Universität zu Köln, Köln, 50674, Germany; Institute of Geochemistry and Petrology, Department of Earth Sciences, ETH Zürich, Zürich, 8092, Switzerland; Institut für Geologie, Universität Bern, Bern, 3012, Switzerland; Department of Geosciences, Eberhard Karls University Tübingen, Tübingen, 72076, Germany; Department of Geology, University of Johannesburg, Auckland Park, 2006, South Africa; Department of Marine Geology, Leibniz Institute for Baltic Sea Research, Rostock, 18119, Germany
推荐引用方式 GB/T 7714	Kurzweil F.,Archer C.,Wille M.,et al. Redox control on the tungsten isotope composition of seawater[J],2021,118(18).
APA	Kurzweil F.,Archer C.,Wille M.,Schoenberg R.,Münker C.,&Dellwig O..(2021).Redox control on the tungsten isotope composition of seawater.Proceedings of the National Academy of Sciences of the United States of America,118(18).
MLA	Kurzweil F.,et al."Redox control on the tungsten isotope composition of seawater".Proceedings of the National Academy of Sciences of the United States of America 118.18(2021).