Publication Name: PESA Journal No. 26
Authors: John D. Gorter
Publication Volume: 26
Date Published: December 1998
Number of Pages: 12
Reference Type: Journal Article
Abstract:
A particular type of source rock contamination isgeographically widespread in the Timor Sea. First
recognised from Bond Petroleum's Avocet 1A, Barita 1, and
Cygnet 1, drilled on the Londonderry High in the late 1980s,
the contamination was attributed to the compound ESSO
Univis J-26. Similar contamination on the C12? saturate
chromatograms has been detected in wells drilled between
1990 and 1992 by different operators. ESSO Univis J-26
has been implicated in increasing the apparent hydrocarbon
potential of argillaceous rocks, which if not recognised
could lead to erroneous conclusions of the generative
capacity of potential petroleum source rocks. The
contaminant occurs in samples with total organic carbon
contents ranging from less than 0.5% to over 4%. As only
some of these samples show evidence of migrated
hydrocarbons, it is concluded that the contaminant has only
minimal effect on source rock quantity.