Dinosterane and other steroidal hydrocarbons of dinoflagellate origin in sediments and petroleum
Abstract
The steroidal alkanes of a selection of sediments and oils have been examined by GC-MS with multiple metastable reaction monitoring. Specific 4-methyl sterane isomers have been identified by comparison with isomers synthesized from sterols isolated from dinoflagellates. An immature marine oil shale and two mature marine oils of Triassic to early Cretaceous age contained high concentrations of C 30 steranes comprising desmethyl, 24-ethyl-4α-methylcholestane and 4α,23,24-trimethylcholestane (dinosterane) isomers. An immature non-marine oil shale and two non-marine oils of Cretaceous to Eocene age contained stereoisomers of 24-ethyl-4α-methylcholestane as the dominant C 30 steranes. Reaction monitoring analyses in GC-MS are particularly suited to unravelling complex distributions of homologous and stereoisomeric steroids encountered in oils and their source rocks.
- Publication:
-
Geochimica et Cosmochimica Acta
- Pub Date:
- November 1987
- DOI:
- 10.1016/0016-7037(87)90381-4
- Bibcode:
- 1987GeCoA..51.3075S