globalchange  > 气候减缓与适应
DOI: 10.1038/ngeo2713
论文题名:
Earth's air pressure 2.7 billion years ago constrained to less than half of modern levels
作者: Som S.M.; Buick R.; Hagadorn J.W.; Blake T.S.; Perreault J.M.; Harnmeijer J.P.; Catling D.C.
刊名: Nature Geoscience
ISSN: 17520894
出版年: 2016
卷: 9, 期:6
起始页码: 448
结束页码: 451
语种: 英语
Scopus关键词: Archean ; argon isotope ; atmospheric pressure ; greenhouse gas ; imprinting ; methane ; paleoclimate ; partial pressure ; raindrop ; size distribution
英文摘要: How the Earth stayed warm several billion years ago when the Sun was considerably fainter is the long-standing problem of the 'faint young Sun paradox'. Because of negligible O2 and only moderate CO2 levels in the Archaean atmosphere, methane has been invoked as an auxiliary greenhouse gas. Alternatively, pressure broadening in a thicker atmosphere with a N2 partial pressure around 1.6-2.4 bar could have enhanced the greenhouse effect. But fossilized raindrop imprints indicate that air pressure 2.7 billion years ago (Gyr) was below twice modern levels and probably below 1.1 bar, precluding such pressure enhancement. This result is supported by nitrogen and argon isotope studies of fluid inclusions in 3.0-3.5 Gyr rocks. Here, we calculate absolute Archaean barometric pressure using the size distribution of gas bubbles in basaltic lava flows that solidified at sea level ∼2.7 Gyr in the Pilbara Craton, Australia. Our data indicate a surprisingly low surface atmospheric pressure of P atm = 0.23 ± 0.23 (2σ) bar, and combined with previous studies suggests ∼0.5 bar as an upper limit to late Archaean P atm. The result implies that the thin atmosphere was rich in auxiliary greenhouse gases and that P atm fluctuated over geologic time to a previously unrecognized extent. © 2016 Macmillan Publishers Limited.
Citation statistics:
资源类型: 期刊论文
标识符: http://119.78.100.158/handle/2HF3EXSE/106000
Appears in Collections:气候减缓与适应
科学计划与规划

Files in This Item:

There are no files associated with this item.


作者单位: Department of Earth and Space Sciences and Astrobiology Program, University of Washington, Seattle, WA, United States; Department of Earth Sciences, Denver Museum of Nature and Science, Denver, CO, United States; School of Earth and Environment, University of Western Australia, 35 Stirling Highway, Crawley, WA, Australia; Blue Marble Space Institute of Science, Seattle, WA, United States; NASA Ames Research Center, Moffett Field, CA, United States; Department of Geology and Geophysics, University of Alaska Fairbanks, Alaska, United States; James Hutton Institute, Invergowrie, Dundee, United Kingdom

Recommended Citation:
Som S.M.,Buick R.,Hagadorn J.W.,et al. Earth's air pressure 2.7 billion years ago constrained to less than half of modern levels[J]. Nature Geoscience,2016-01-01,9(6)
Service
Recommend this item
Sava as my favorate item
Show this item's statistics
Export Endnote File
Google Scholar
Similar articles in Google Scholar
[Som S.M.]'s Articles
[Buick R.]'s Articles
[Hagadorn J.W.]'s Articles
百度学术
Similar articles in Baidu Scholar
[Som S.M.]'s Articles
[Buick R.]'s Articles
[Hagadorn J.W.]'s Articles
CSDL cross search
Similar articles in CSDL Cross Search
[Som S.M.]‘s Articles
[Buick R.]‘s Articles
[Hagadorn J.W.]‘s Articles
Related Copyright Policies
Null
收藏/分享
所有评论 (0)
暂无评论
 

Items in IR are protected by copyright, with all rights reserved, unless otherwise indicated.