气候变化领域集成服务门户(CCPortal): Uranium isotope evidence for Mesoarchean biological oxygen production in shallow marine and continental settings

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DOI	10.1016/j.epsl.2020.116583
	Uranium isotope evidence for Mesoarchean biological oxygen production in shallow marine and continental settings
	Wang X.; Ossa Ossa F.; Hofmann A.; Agangi A.; Paprika D.; Planavsky N.J.
发表日期	2020
ISSN	0012821X
卷号	551
英文摘要	Oxidative weathering of continental rocks is the major source of redox-sensitive elements to the ocean. The timing for the initiation of oxidative weathering remains strongly debated. Here we report new δ238U data for the authigenic component of well-preserved ca. 3.07–2.90 Ga marine and lacustrine shales from the Mozaan and Dominion groups of the Kaapvaal Craton, South Africa. The δ238Uauth values in marine shales (−0.71‰ to −0.21‰ relative to CRM 112a) are lower than the bulk silicate Earth (BSE, −0.40‰ to −0.17‰), while those of lacustrine shales (−0.68‰ to 0.05‰) scatter above and below the BSE range. In addition, the δ238Uauth values of marine shales deposited in shallow seawater are significantly lower than those of the shales deposited in deep seawater. We propose that U(VI) was adsorbed onto Fe-Mn oxides in oxic shallow water and then shuttled to the seafloor. The U isotope fractionations in lacustrine shales are best explained by reduction of U(VI) to U(IV) below the sediment-water interface. Together, these observations bolster the case that a mildly oxidative weathering regime had been established at the Earth's surface by ∼3.0 Ga, paving the way to the onset of aerobic metabolism in both continental and shallow marine environments. © 2020 Elsevier B.V.
关键词	Archean oxygen paleoredox proxy photosynthesis uranium isotopes
英文关键词	Iron oxides; Isotopes; Manganese removal (water treatment); Oxygen; Seawater; Silicates; Bulk silicate earth; Earth's surface; Isotope fractionation; Oxidative weathering; Oxygen production; Redox sensitives; Sediment water interface; Uranium isotopes; Weathering; Archean; continental margin; depositional environment; marine environment; oxygen; paleoenvironment; photosynthesis; redox conditions; shallow water; uranium isotope; Kaapvaal Craton
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/202960
作者单位	University of South Alabama, Mobile, AL, United States; Dauphin Island Sea Lab, Dauphin Island, AL, United States; University of Tuebingen, Tuebingen, 72074, Germany; University of Johannesburg, Auckland Park, 2006, South Africa; Akita University, Tegata Gakuen machi010-8502, Japan; Yale University, New Haven, CT, United States
推荐引用方式 GB/T 7714	Wang X.,Ossa Ossa F.,Hofmann A.,et al. Uranium isotope evidence for Mesoarchean biological oxygen production in shallow marine and continental settings[J],2020,551.
APA	Wang X.,Ossa Ossa F.,Hofmann A.,Agangi A.,Paprika D.,&Planavsky N.J..(2020).Uranium isotope evidence for Mesoarchean biological oxygen production in shallow marine and continental settings.Earth and Planetary Science Letters,551.
MLA	Wang X.,et al."Uranium isotope evidence for Mesoarchean biological oxygen production in shallow marine and continental settings".Earth and Planetary Science Letters 551(2020).