Analysis and occurrence of C26-steranes in petroleum and source rocks

  title={Analysis and occurrence of C26-steranes in petroleum and source rocks},
  author={J. Michael Moldowan and Cathy Y. Lee and David S. Watt and Alwarsamy Jeganathan and N. Slougui and Emilio J. Gallegos},
  journal={Geochimica et Cosmochimica Acta},
Abstract The C26-steranes previously reported in oils and source rocks (MOLDOWAN et al., 1985) have been identified as 21-, 24-, and 27-norcholestanes (1A, 1B, and 1C). Various 24-norcholesterols or stanols, possible precursors for the 24-norcholestanes, occur widely at low levels in marine invertebrates and some algae, and 24-norcholestanes occur in marine petroleums of Tertiary through Paleozoic age. There are reports of 27-norcholesterols and stanols in recent sediments, but the precursor… Expand
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