Isotopes, ice ages, and terminal Proterozoic earth history.

  title={Isotopes, ice ages, and terminal Proterozoic earth history.},
  author={Alan J Kaufman and Andrew H. Knoll and Guy M. Narbonne},
  journal={Proceedings of the National Academy of Sciences of the United States of America},
  volume={94 13},
Detailed correlations of ancient glacial deposits, based on temporal records of carbon and strontium isotopes in seawater, indicate four (and perhaps five) discrete ice ages in the terminal Proterozoic Eon. The close and repeated stratigraphic relationship between C-isotopic excursions and glaciogenic rocks suggests that unusually high rates of organic carbon burial facilitated glaciation by reducing atmospheric greenhouse capacity. The emerging framework of time and environmental change… 
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