气候变化领域集成服务门户(CCPortal): Organic matter from the Chicxulub crater exacerbated the K-Pg impact winter

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DOI	10.1073/pnas.2004596117
	Organic matter from the Chicxulub crater exacerbated the K-Pg impact winter
	Lyons S.L.; Karp A.T.; Bralower T.J.; Grice K.; Schaefer B.; Gulick S.P.S.; Morgan J.V.; Freeman K.H.
发表日期	2020
ISSN	0027-8424
起始页码	25327
结束页码	25334
卷号	117 期号:41
英文摘要	An asteroid impact in the Yucatán Peninsula set off a sequence of events that led to the Cretaceous-Paleogene (K-Pg) mass extinction of 76% species, including the nonavian dinosaurs. The impact hit a carbonate platform and released sulfate aerosols and dust into Earth's upper atmosphere, which cooled and darkened the planet - a scenario known as an impact winter. Organic burn markers are observed in K-Pg boundary records globally, but their source is debated. If some were derived from sedimentary carbon, and not solely wildfires, it implies soot from the target rock also contributed to the impact winter. Characteristics of polycyclic aromatic hydrocarbons (PAHs) in the Chicxulub crater sediments and at two deep ocean sites indicate a fossil carbon source that experienced rapid heating, consistent with organic matter ejected during the formation of the crater. Furthermore, PAH size distributions proximal and distal to the crater indicate the ejected carbon was dispersed globally by atmospheric processes. Molecular and charcoal evidence indicates wildfires were also present but more delayed and protracted and likely played a less acute role in biotic extinctions than previously suggested. Based on stratigraphy near the crater, between 7.5 × 1014and 2.5 × 1015g of black carbon was released from the target and ejected into the atmosphere, where it circulated the globe within a few hours. This carbon, together with sulfate aerosols and dust, initiated an impact winter and global darkening that curtailed photosynthesis and is widely considered to have caused the K-Pg mass extinction. © 2020 National Academy of Sciences. All rights reserved.
英文关键词	Chicxulub impact crater; Cretaceous-Paleogene; Impact winter; Polycyclic aromatic hydrocarbons; Wildfires
语种	英语
scopus关键词	black carbon; carbon; carbonic acid; organic matter; polycyclic aromatic hydrocarbon; sulfate; aerosol; Article; atmosphere; carbon source; dust; end Cretaceous mass extinction; heating; impact winter; natural science; photosynthesis; priority journal; reaction duration (chemistry); sea; sediment; stratigraphy; wildfire
来源期刊	Proceedings of the National Academy of Sciences of the United States of America
文献类型	期刊论文
条目标识符	http://gcip.llas.ac.cn/handle/2XKMVOVA/160212
作者单位	Lyons, S.L., Department of Geosciences, Pennsylvania State University, University Park, PA 16802, United States; Karp, A.T., Department of Geosciences, Pennsylvania State University, University Park, PA 16802, United States; Bralower, T.J., Department of Geosciences, Pennsylvania State University, University Park, PA 16802, United States; Grice, K., Western Australia Organic and Isotope Geochemistry Centre, School of Earth and Planetary Sciences, Institute for Geoscience Research, Curtin University, Perth, WA 6102, Australia; Schaefer, B., Western Australia Organic and Isotope Geochemistry Centre, School of Earth and Planetary Sciences, Institute for Geoscience Research, Curtin University, Perth, WA 6102, Australia; Gulick, S.P.S., Institute for Geophysics, University of Texas at Austin, Austin, TX 78758, United States, Department of Geological Sciences, University of Texas at Austin, Austin, TX 78712, United States, Center for Planetary Systems Habitability, University of Texas at Austin, Austin, ...
推荐引用方式 GB/T 7714	Lyons S.L.,Karp A.T.,Bralower T.J.,et al. Organic matter from the Chicxulub crater exacerbated the K-Pg impact winter[J],2020,117(41).
APA	Lyons S.L..,Karp A.T..,Bralower T.J..,Grice K..,Schaefer B..,...&Freeman K.H..(2020).Organic matter from the Chicxulub crater exacerbated the K-Pg impact winter.Proceedings of the National Academy of Sciences of the United States of America,117(41).
MLA	Lyons S.L.,et al."Organic matter from the Chicxulub crater exacerbated the K-Pg impact winter".Proceedings of the National Academy of Sciences of the United States of America 117.41(2020).