New triaromatic steroids distinguish Paleozoic from Mesozoic oil

• Published in: Organic geochemistry 2011-05, Vol.42 (4), p.409-424
• Main Authors: Barbanti, Silvana M., Moldowan, J. Michael, Watt, David S., Kolaczkowska, E.
• Format: Article
• Language: English
• Subjects: Bacillariophyceae; biomarkers; Dinophyceae; Earth sciences; Earth, ocean, space; Exact sciences and technology; extinction; Geochemistry; global change; Haptophyta; oils; Paleobotany; paleoclimatology; Paleontology; petroleum; Soil and rock geochemistry; steroids; Stratigraphy; trophic relationships
• ISSN: 0146-6380; 1873-5290
• DOI: 10.1016/j.orggeochem.2011.02.007

Certain biomarkers in petroleum provide information on of the geologic age of its source rock and these can also be used to track the evolution, radiation and relationships between taxa and as proxies for paleoenvironmental reconstruction. Triaromatic 23,24-dimethylcholesteroids (TA-DMC), which undoubtedly derive from 23,24-dimethylcholesterols in dinoflagellates, haptophytes and diatoms, provide a useful parameter to distinguish Paleozoic from Mesozoic and younger oil and rock extracts at higher specificity than previously proposed biomarkers. In this report, we present a study of the relative abundance of a novel series of TA-DMC in source rock extracts and crude oil from different global localities and ages. Based on their taxon specificity for important primary producers, such biogeochemicals also have implications for paleoenvironmental studies, including paleoclimate and global change, such as radiations following the Permian–Triassic boundary mass extinction.