气候变化领域集成服务门户(CCPortal): Using Stable Isotopes to Disentangle Marine Sedimentary Signals in Reactive Silicon Pools

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DOI	10.1029/2020GL087877
	Using Stable Isotopes to Disentangle Marine Sedimentary Signals in Reactive Silicon Pools
	Pickering R.A.; Cassarino L.; Hendry K.R.; Wang X.L.; Maiti K.; Krause J.W.
发表日期	2020
ISSN	0094-8276
卷号	47 期号:15
英文摘要	Many studies use sedimentary biogenic silica (bSiO2) stable isotopes (e.g., δ30Si) as paleoproxies but neglect signals from other sedimentary reactive SiO2 phases. We quantified δ30Si for multiple reactive Si pools in coastal river-plume sediments, revealing up to −5‰ difference between acid-leachable and alkaline-digestible amorphous SiO2. Thus, previous studies have missed valuable information on early diagenetic products and, in cases where sediments were not cleaned, potentially biased bSiO2 δ30Si values. Acid-leachable δ30Si, that is, from authigenic products, are the result of either multistep fractionation from a bSiO2 source or an ~2‰ fractionation (consistent with metal hydroxide formation) from slowly dissolving lithogenic SiO2. This analysis also suggests that sedimentary diatom bSiO2, which has increased regionally in the last half-century, is the critical substrate of early authigenic Si precipitates. Regional eutrophication, which has stimulated sedimentary bSiO2 accumulation, may have facilitated additional sequestration of both sedimentary Si and cations from early diagenetic products. © 2020. American Geophysical Union. All Rights Reserved.
英文关键词	Amorphous silicon; Eutrophication; Isotopes; River pollution; Sedimentology; Silica; Silicon oxides; Amorphous SiO2; Biogenic silica; Coastal rivers; Diagenetics; Metal hydroxide; Multi-step; Si precipitates; Stable isotopes; Silicon; alkalinity; isotopic fractionation; precipitation (chemistry); sediment chemistry; silica; silicon; stable isotope; Bacillariophyta
语种	英语
来源期刊	Geophysical Research Letters
文献类型	期刊论文
条目标识符	http://gcip.llas.ac.cn/handle/2XKMVOVA/170037
作者单位	Dauphin Island Sea Laboratory, Dauphin Island, AL, United States; Department of Marine Sciences, University of South Alabama, Mobile, AL, United States; School of Earth Sciences, University of Bristol, Bristol, United Kingdom; Department of Oceanography and Coastal Studies, Louisiana State University, Baton Rouge, LA, United States
推荐引用方式 GB/T 7714	Pickering R.A.,Cassarino L.,Hendry K.R.,et al. Using Stable Isotopes to Disentangle Marine Sedimentary Signals in Reactive Silicon Pools[J],2020,47(15).
APA	Pickering R.A.,Cassarino L.,Hendry K.R.,Wang X.L.,Maiti K.,&Krause J.W..(2020).Using Stable Isotopes to Disentangle Marine Sedimentary Signals in Reactive Silicon Pools.Geophysical Research Letters,47(15).
MLA	Pickering R.A.,et al."Using Stable Isotopes to Disentangle Marine Sedimentary Signals in Reactive Silicon Pools".Geophysical Research Letters 47.15(2020).