Age- and Source-Specific Hydroaromatic Biomarkers in the Beaufort-Mackenzie Basin

Maowen Li, Lloyd Snowdon, and Dale Issler
Geological Survey of Canada, Calgary, AB

The extracts isolated from several potential petroleum source rocks in the Beaufort-Mackenzie Basin contain complex mixtures of polycyclic hydroaromatic hydrocarbons. A number of tri-, tetra- and penta-cyclic hydroaromatic hydrocarbons derived from both common and rare natural product di- and tri-terpenoids, with various degrees of unsaturation, were identified from the Tertiary sediments including the Taglu Sequence, by comparison with synthetic standards or mass spectral interpretations. The peculiar geographical distribution of Early-Middle Eocene-age sediments bearing these compounds in high concentrations in immature to marginally mature samples implies the early diagenetic transformation of various plant material under acidic conditions, most likely by microbial action. A study of other potential source rocks in this basin indicates that these compounds are promising as specific markers complementing the aliphatic hydrocarbons and thus serve as diagnostic parameters for oil-source correlation.

AAPG Search and Discovery Article #90039©2005 AAPG Calgary, Alberta, June 16-19, 2005