气候变化领域集成服务门户(CCPortal): Delayed and variable late Archaean atmospheric oxidation due to high collision rates on Earth

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DOI	10.1038/s41561-021-00835-9
	Delayed and variable late Archaean atmospheric oxidation due to high collision rates on Earth
	Marchi S.; Drabon N.; Schulz T.; Schaefer L.; Nesvorny D.; Bottke W.F.; Koeberl C.; Lyons T.
发表日期	2021
ISSN	1752-0894
卷号	14 期号:11
英文摘要	Frequent violent collisions of impactors from space punctuated the geological and atmospheric evolution of early Earth. It is generally accepted that the most massive collisions altered the chemistry of Earth’s earliest atmosphere, but the consequences of Archaean collisions for atmospheric oxidation are little understood. Early Archaean (4.0–3.5 billion years ago (Ga)) impact flux models are tightly constrained by lunar cratering and radiometric data. Further, a record of the late Archaean (3.5–2.5 Ga) impact flux is provided by terrestrial impact spherule layers—formed by collisions with bodies ≥10–20 km in diameter—although this record is probably incomplete and significant uncertainties remain. Here we show, on the basis of an assessment of impactor-related spherule records and modelling of the atmospheric effects of these impacts, that current bombardment models underestimate the number of late Archaean spherule layers. These findings suggest that the late Archaean impactor flux was up to a factor of ten higher than previously thought. We find that the delivered impactor mass was an important sink of oxygen, suggesting that early bombardment could have delayed Earth’s atmosphere oxidation. In addition, late Archaean large impacts (≥10 km) probably caused drastic oscillations of atmospheric oxygen, with an average time between consecutive collisions of about 15 Myr. This pattern is consistent with a known episode of atmospheric oxygen oscillation at ~2.5 Ga that is bracketed by large impacts recorded by Bee Gorge (~2.54 Ga) and Dales Gorge (~2.49 Ga) spherule layers. © 2021, The Author(s), under exclusive licence to Springer Nature Limited.
语种	英语
scopus关键词	Archean; atmospheric chemistry; collision; cratering; Earth; oxidation; radiometric method; Australia; Dales Gorge; Western Australia
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/250845
作者单位	Southwest Research Institute, Boulder, CO, United States; Department of Geological Sciences, Stanford University, Stanford, CA, United States; Harvard University, Department of Earth and Planetary Sciences, Cambridge, MA, United States; Department of Lithospheric Research, University of Vienna, Vienna, Austria; Institut für Geologie und Mineralogie, Universität zu Köln, Köln, Germany; Department of Earth and Planetary Sciences, University of California, Riverside, CA, United States
推荐引用方式 GB/T 7714	Marchi S.,Drabon N.,Schulz T.,et al. Delayed and variable late Archaean atmospheric oxidation due to high collision rates on Earth[J],2021,14(11).
APA	Marchi S..,Drabon N..,Schulz T..,Schaefer L..,Nesvorny D..,...&Lyons T..(2021).Delayed and variable late Archaean atmospheric oxidation due to high collision rates on Earth.Nature Geoscience,14(11).
MLA	Marchi S.,et al."Delayed and variable late Archaean atmospheric oxidation due to high collision rates on Earth".Nature Geoscience 14.11(2021).