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arXiv · 1405.6337

Nitrogen Isotopic Composition and Density of the Archean Atmosphere

Bernard Marty·Laurent Zimmermann·Magali Pujol·Ray Burgess·Pascal Philippot
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Abstract

Understanding the atmosphere's composition during the Archean eon is a fundamental issue to unravel ancient environmental conditions. We show from the analysis of nitrogen and argon isotopes in fluid inclusions trapped in 3.0-3.5 Ga hydrothermal quartz that the PN2 of the Archean atmosphere was lower than 1.1 bar, possibly as low as 0.5 bar, and had a nitrogen isotopic composition comparable to the present-day one. These results imply that dinitrogen did not play a significant role in the thermal budget of the ancient Earth and that the Archean PCO2 was probably lower than 0.7 bar.

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Bernard Marty, Laurent Zimmermann, Magali Pujol, Ray Burgess, Pascal Philippot. 2014-05-24. Nitrogen Isotopic Composition and Density of the Archean Atmosphere. https://doi.org/10.1126/science.1240971

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