MP9: Chapter 11: Petrophysical Properties of Ophiomorpha irregulaire Ichnofabrics from BN L-55 of Hebron Field, Offshore Newfoundland
by M.K. Leaman and Duncan McIlroy.
Requires 1 download. Click on 'Members Only', then 'My Information' to see available downloads after payment is processed.
This chapter is from GAC's Miscellaneous Publication 9: "Ichnology: Papers from Ichnia III" editted by Dr. Duncan McIlroy. To purchase the entire book on disc, please see the Miscellaneous Publications section of our bookstore at http://www.gac.ca/publications/view_pub.php?id=262.
Ophiomorpha is the dominant ichnofabric-forming trace fossil in many bioturbated siliciclastic petroleum reservoirs worldwide, but its effect on reservoir permeability, especially in three dimensions, is not fully understood. Four different Ophiomorpha-dominated ichnofabrics, in cores from the Ben Nevis Formation in the L-55 Ben Nevis well of the Jeanne dArc Basin, offshore Newfoundland, were mapped using spot-permeametry measurements. Integration of spot-permeametry data and volumetric analysis allows us to conclude that burrows of Ophiomorpha irregulaire reduce kh by an average of 28% and kv can be decreased by 14%.
The volumetric and petrophysical study of ichnofabrics allow ichnology to become an integral part of reservoir characterization studies. With an understanding of burrow volume and its effect on reservoir quality at the core scale, it becomes possible to make first-order interpretations and predictions of reservoir quality on a reservoir-wide scale. Study of ichnofabrics through a succession, allows prediction of the intensity of bioturbation on a facies by facies basis. Variability in ichnofabrics within facies elements makes realistic first-order predictions of lateral variability, connectivity of trace fossils, and therefore reservoir properties possible. This work demonstrates that careful integration of petrophysical and ichnological analysis has the potential to greatly inform exploration for, and production from, bioturbated reservoir intervals.
Geological Association of Canada
<< Go Back