Abstract: Plant-Derived
Aromatic Biomarkers for Oil - Source Rock Correlation in an Australian
Jurassic Petroleum
System
VAN AARSSEN, B. G. K., R. ALEXANDER*, and R. I. KAGI
New biomarker technology
has been developed that enables precise correlation of crude oils with
the sediments that sourced the oils. This correlation technique is based
on the biomarker fingerprint provided by the plants that occupied the drainage
system
of the basin during sedimentation. Changes in plant habitats caused
by tectonic events, eustatic effects and climate instigate alterations
in the plant populations. These alterations are reflected in the composition
of the plant-derived biomarkers incorporated into the marine sediments.
The biomarker fingerprint provided by the plants thus changes through time
in response to these events. The fingerprint obtained from a crude oil
can be compared with the profile through time of the sedimentary fingerprint
to get a precise age for the sediments that sourced the oil.
A fingerprint profile for sediments of Jurassic age was established from a study of samples at Koolinda-1 in the Barrow Sub-basin. A sample suite of 20 crude oils from widely distributed locations show plant-derived biomarker fingerprints that correlate with sediments within a small age range. These results show that only sediments from a limited time window have sourced the major crude oil accumulations of the Barrow Sub-basin.
AAPG Search and Discovery Article #90942©1997 AAPG International Conference and Exhibition, Vienna, Austria