气候变化领域集成服务门户(CCPortal): A high-TOC shale in a low productivity world: The late Mesoproterozoic Arctic Bay Formation, Nunavut

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DOI	10.1016/j.epsl.2020.116384
	A high-TOC shale in a low productivity world: The late Mesoproterozoic Arctic Bay Formation, Nunavut
	Hodgskiss M.S.W.; Sansjofre P.; Kunzmann M.; Sperling E.A.; Cole D.B.; Crockford P.W.; Gibson T.M.; Halverson G.P.
发表日期	2020
ISSN	0012821X
卷号	544
英文摘要	The latest Mesoproterozoic Arctic Bay Formation (Borden Basin, Nunavut, Canada) is up to ∼1130 m-thick and contains a significant proportion of unusually organic-rich black shale (up to 12.3 wt% total organic carbon). Insofar as increased biological productivity is related to organic matter burial, this organic-rich succession is seemingly incongruent with the low biological productivity world hypothesised for much of the Proterozoic. To better understand the conditions leading to development of this organic-rich unit, we explore the redox geochemistry of the Arctic Bay Formation using a multi-proxy approach (nitrogen isotopes, iron speciation, total organic carbon, total sulphur, and trace metal abundances). Redox proxy data support a stratified water column, with oxic surface waters underlain by intermittently euxinic waters, which are in turn underlain by persistently ferruginous deeper waters. The highly alkaline, restricted marine basin in which the Arctic Bay Formation was deposited may have allowed for rapid sequestration of highly reactive iron in carbonate minerals, resulting in an ‘excess’ of sulphur that resulted in sulphurisation of organic matter. Estimates for organic matter burial rates during deposition of the Arctic Bay Formation suggest that they were perhaps ∼5–6 times mid-Proterozoic average values (although there are permissible scenarios in which it was extremely productive), underscoring that such organic-rich sedimentary rocks could be produced in a low productivity world. © 2020
关键词	Arctic Bay Formation Mesoproterozoic redox shale sulphurisation TOC
英文关键词	Biogeochemistry; Ecology; Iron compounds; Organic minerals; Productivity; Shale; Surface waters; Trace elements; Average values; Biological productivity; Iron speciations; Marine basins; Nitrogen isotopes; Organic matter burial; Stratified waters; Total Organic Carbon; Organic carbon; biological production; iron; organic matter; Proterozoic; sediment chemistry; sedimentary rock; shale; total organic carbon; water column; Arctic Bay; Baffin Island; Canada; Nunavut; Nunavut
语种	英语
来源期刊	Earth and Planetary Science Letters
文献类型	期刊论文
条目标识符	http://gcip.llas.ac.cn/handle/2XKMVOVA/202650
作者单位	Department of Geological Sciences, Stanford University, Stanford, CA, United States; Muséum National d'Histoire Naturelle, Sorbonne Université, CNRS UMR 7590, Institut de Minéralogie, de Physique des Matériaux et de Cosmochimie, Paris, France; CSIRO Mineral Resources, Australian Resources Research Centre, Kensington, WA, Australia; School of Earth and Atmospheric Sciences, Georgia Institute of Technology, Atlanta, GA, United States; Department of Earth and Planetary Sciences, Weizmann Institute of Science, Rehovot, Israel; Department of Geoscience, Princeton University, Princeton, NJ, United States; Department of Earth Sciences, Dartmouth College, Hanover, NH, United States; Department of Earth & Planetary Sciences, McGill University, Montréal, QC, Canada
推荐引用方式 GB/T 7714	Hodgskiss M.S.W.,Sansjofre P.,Kunzmann M.,et al. A high-TOC shale in a low productivity world: The late Mesoproterozoic Arctic Bay Formation, Nunavut[J],2020,544.
APA	Hodgskiss M.S.W..,Sansjofre P..,Kunzmann M..,Sperling E.A..,Cole D.B..,...&Halverson G.P..(2020).A high-TOC shale in a low productivity world: The late Mesoproterozoic Arctic Bay Formation, Nunavut.Earth and Planetary Science Letters,544.
MLA	Hodgskiss M.S.W.,et al."A high-TOC shale in a low productivity world: The late Mesoproterozoic Arctic Bay Formation, Nunavut".Earth and Planetary Science Letters 544(2020).