气候变化领域集成服务门户(CCPortal): Unique Neoproterozoic carbon isotope excursions sustained by coupled evaporite dissolution and pyrite burial

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DOI	10.1038/s41561-019-0434-3
	Unique Neoproterozoic carbon isotope excursions sustained by coupled evaporite dissolution and pyrite burial
	Shields G.A.; Mills B.J.W.; Zhu M.; Raub T.D.; Daines S.J.; Lenton T.M.
发表日期	2019
ISSN	17520894
卷号	12 期号:10
英文摘要	The Neoproterozoic era witnessed a succession of biological innovations that culminated in diverse animal body plans and behaviours during the Ediacaran–Cambrian radiations. Intriguingly, this interval is also marked by perturbations to the global carbon cycle, as evidenced by extreme fluctuations in climate and carbon isotopes. The Neoproterozoic isotope record has defied parsimonious explanation because sustained 12C-enrichment (low δ13C) in seawater seems to imply that substantially more oxygen was consumed by organic carbon oxidation than could possibly have been available. We propose a solution to this problem, in which carbon and oxygen cycles can maintain dynamic equilibrium during negative δ13C excursions when surplus oxidant is generated through bacterial reduction of sulfate that originates from evaporite weathering. Coupling of evaporite dissolution with pyrite burial drives a positive feedback loop whereby net oxidation of marine organic carbon can sustain greenhouse forcing of chemical weathering, nutrient input and ocean margin euxinia. Our proposed framework is particularly applicable to the late Ediacaran ‘Shuram’ isotope excursion that directly preceded the emergence of energetic metazoan metabolisms during the Ediacaran–Cambrian transition. Here we show that non-steady-state sulfate dynamics contributed to climate change, episodic ocean oxygenation and opportunistic radiations of aerobic life during the Neoproterozoic era. © 2019, The Author(s), under exclusive licence to Springer Nature Limited.
语种	英语
scopus关键词	biostratigraphy; body condition; carbon isotope; dissolution; Ediacaran; evaporite; metazoan; microfossil; oxidation; oxygenation; Proterozoic; pyrite; Animalia; Bacteria (microorganisms); Metazoa
来源期刊	Nature Geoscience
文献类型	期刊论文
条目标识符	http://gcip.llas.ac.cn/handle/2XKMVOVA/124598
作者单位	Department of Earth Sciences, University College London, London, United Kingdom; School of Earth and Environment, University of Leeds, Leeds, United Kingdom; State Key Laboratory of Palaeobiology and Stratigraphy & Center for Excellence in Life and Paleoenvironment, Nanjing Institute of Geology and Palaeontology, Chinese Academy of Sciences, Nanjing, China; College of Earth and Planetary Sciences, University of Chinese Academy of Sciences, Beijing, China; School of Earth and Environmental Sciences, University of St Andrews, St Andrews, United Kingdom; Global Systems Institute, University of Exeter, Exeter, United Kingdom
推荐引用方式 GB/T 7714	Shields G.A.,Mills B.J.W.,Zhu M.,et al. Unique Neoproterozoic carbon isotope excursions sustained by coupled evaporite dissolution and pyrite burial[J],2019,12(10).
APA	Shields G.A.,Mills B.J.W.,Zhu M.,Raub T.D.,Daines S.J.,&Lenton T.M..(2019).Unique Neoproterozoic carbon isotope excursions sustained by coupled evaporite dissolution and pyrite burial.Nature Geoscience,12(10).
MLA	Shields G.A.,et al."Unique Neoproterozoic carbon isotope excursions sustained by coupled evaporite dissolution and pyrite burial".Nature Geoscience 12.10(2019).