Geological sulfur isotopes indicate elevated OCS in the Archean atmosphere, solving faint young sun paradox
نویسندگان
چکیده
منابع مشابه
Mass-independent fractionation of sulfur isotopes in Archean sediments: strong evidence for an anoxic Archean atmosphere.
Mass-independent fractionation (MIF) of sulfur isotopes has been reported in sediments of Archean and Early Proterozoic Age (> 2.3 Ga) but not in younger rocks. The only fractionation mechanism that is consistent with the data on all four sulfur isotopes involves atmospheric photochemical reactions such as SO2 photolysis. We have used a one-dimensional photochemical model to investigate how the...
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Given a solar luminosity LAr = 0.75L0 at the beginning of the Archean 3.8 Ga ago, where L0 is the present-day one, if the heliocentric distance, r, of the Earth was rAr = 0.956r0, the solar irradiance would have been as large as IAr = 0.82I0. It would have allowed for a liquid ocean on the terrestrial surface, which, otherwise, would have been frozen, contrary to the empirical evidence. By furt...
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ژورنال
عنوان ژورنال: Proceedings of the National Academy of Sciences
سال: 2009
ISSN: 0027-8424,1091-6490
DOI: 10.1073/pnas.0903518106