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DOI	10.1016/j.palaeo.2020.109598
	Variations of redox conditions in the atmosphere and Yangtze Platform during the Ediacaran-Cambrian transition: Constraints from Cr isotopes and Ce anomalies
	Wei W.; Frei R.; Gilleaudeau G.J.; Li D.; Wei G.-Y.; Huang F.; Ling H.-F.
发表日期	2020
ISSN	0031-0182
卷号	543
英文摘要	The Ediacaran-Cambrian transition was characterized by the evolution from Ediacaran soft-body to Cambrian skeletal organisms, and fluctuations of the marine carbon cycle. Marine redox changes should have played an essential role in both ecological and environmental evolutions; however, temporary changes and spatial distribution of redox conditions in the Ediacaran-Cambrian oceans remain elusive and highly debated. In this study, we analyzed chromium (Cr) isotope and cerium (Ce) anomaly profiles in carbonates from the Upper Ediacaran-Lower Cambrian Dengying and Zhujiaqing formations at the Xiaotan section, South China, in an attempt to provide new insights helping unravel Earth's surface redox changes during the Ediacaran-Cambrian transition. Our results show that these carbonates record generally positive δ53Crauth values (up to 1.15‰) with fluctuations and prominent negative Ce anomalies (Ce/Ce⁎ values down to 0.35), implying a broad increase in oxygenation in the atmosphere and the inner shelf of the Yangtze Platform during the Ediacaran-Cambrian transition. The first appearance and subsequent diversification of the Cambrian animals may have benefited from this oxygenation event. The pronounced fluctuations of δ53Crauth and δ13Ccarb values can be explained by episodic oxidation of a deep-water DOC pool in a stratified water column across the chemocline through upwelling, releasing light carbon isotopes and organic-matter-bound isotopically unfractionated Cr (III) into shallow waters. © 2020 Elsevier B.V.
英文关键词	Carbon cycle; Carbonates; Oxygenation; SSFs; Xiaotan section
语种	英语
scopus关键词	anomaly; Cambrian; carbon cycle; cerium; chromium; Ediacaran; isotopic composition; oxygenation; paleoceanography; paleoenvironment; redox conditions; China; Yangtze Platform; Animalia
来源期刊	Palaeogeography, Palaeoclimatology, Palaeoecology
文献类型	期刊论文
条目标识符	http://gcip.llas.ac.cn/handle/2XKMVOVA/150590
作者单位	CAS Key Laboratory of Crust–Mantle Materials and Environments, School of Earth and Space Sciences, University of Science and Technology of China, Hefei, Anhui 230026, China; State Key Laboratory for Mineral Deposits Research, School of Earth Sciences and Engineering, Nanjing University, Nanjing, Jiangsu 210023, China; Department of Geosciences and Natural Resource Management, University of Copenhagen, Øster Voldgade 10, Copenhagen, 1350, Denmark; Department of Atmospheric, Oceanic and Earth Sciences, George Mason University, United States; School of Marine Science and Engineering, Nanjing Normal University, Nanjing, Jiangsu 210023, China
推荐引用方式 GB/T 7714	Wei W.,Frei R.,Gilleaudeau G.J.,et al. Variations of redox conditions in the atmosphere and Yangtze Platform during the Ediacaran-Cambrian transition: Constraints from Cr isotopes and Ce anomalies[J],2020,543.
APA	Wei W..,Frei R..,Gilleaudeau G.J..,Li D..,Wei G.-Y..,...&Ling H.-F..(2020).Variations of redox conditions in the atmosphere and Yangtze Platform during the Ediacaran-Cambrian transition: Constraints from Cr isotopes and Ce anomalies.Palaeogeography, Palaeoclimatology, Palaeoecology,543.
MLA	Wei W.,et al."Variations of redox conditions in the atmosphere and Yangtze Platform during the Ediacaran-Cambrian transition: Constraints from Cr isotopes and Ce anomalies".Palaeogeography, Palaeoclimatology, Palaeoecology 543(2020).