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Science 12 March 1971:
Vol. 171. no. 3975, pp. 1015 - 1016
DOI: 10.1126/science.171.3975.1015
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Articles

Sulfur Isotopes in Swaziland System Barites and the Evolution of the Earth's Atmosphere

Eugene C. Perry Jr. 1, Jan Monster 2, and Thomas Reimer 3

1 Minnesota Geological Survey, University of Minnesota, Minneapolis 55455
2 McMaster University, Hamilton, Ontario, Canada
3 University of the Witwatersrand, Johannesburg, South Africa

Sedimentary barites from the Swaziland System of South Africa (more than 3000 million years old) have sulfur-34 ratios that are enriched by only 2.5 per mil with respect to contemporary sulfides. To explain this small fractionation, it is proposed that oxygen pressure in the earth's atmosphere was very low and that local oxidation occurred in a photosynthetic layer of the ocean.


THIS ARTICLE HAS BEEN CITED BY OTHER ARTICLES:
Active Microbial Sulfur Disproportionation in the Mesoproterozoic.
D. T. Johnston, B. A. Wing, J. Farquhar, A. J. Kaufman, H. Strauss, T. W. Lyons, L. C. Kah, and D. E. Canfield (2005)
Science 310, 1477-1479
   Abstract »    Full Text »    PDF »
Earth and Mars: Evolution of Atmospheres and Surface Temperatures.
C. Sagan, C. Sagan, and G. Mullen (1972)
Science 177, 52-56
   Abstract »    PDF »


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