Journal of Conference Abstracts

Upper Devonian Carbonate Buildups Impersonating Paradox Basin Phylloid Algal Mounds

Dave Eby (EPCEby@aol.com)

Eby Petrography & Consulting, Inc., 2200 West Berry Ave., Littleton, CO, USA 80120

Pennsylvanian phylloid algal carbonate buildups in the Paradox Basin of the Four Corners area (USA) have been oil and gas exploration targets for nearly fifty years. Recently, these carbonate reservoirs with their distinctive "platy framework" components have been used as a model for a new play type in the Upper Devonian of western Canada. Muddy limestone mounds with platy stromatoporoids exhibit geometries, vertical stacking and porosity types that resemble the prolific phylloid algal mounds of the Ismay and Desert Creek intervals of the Paradox Formation, SE Utah and SW Colorado. Dr. Jack Wendte (currently with the Geological Survey of Canada) has pioneered the use of a phylloid algal mound analogue for interpreting the Devonian platy mounds currently being exploited over a wide area in NE British Columbia. Field work and subsurface studies on Paradox Basin carbonate buildups by an on-going Utah Geological Survey/DOE project provide significant insights into what might be expected in this new mound play within the Western Canadian Sedimentary Basin. In addition, outcrops and quarry faces of Upper Devonian platy mounds in eastern Europe show three-dimensional analogs to the new Canadian exploration play. Horizontal drilling has been particularly useful during the early exploitation activities within clusters of these platy mounds in western Canada.

Some "food for thought" questions about the future of platy carbonate mound petroleum plays:

(1) Could these types of buildups be economic exploration targets in the Devonian of eastern Europe, Alberta, Nevada or Australia?

(2) Will horizontal drilling provide an attractive exploration/exploitation tool in Paradox Penn buildups as it has been in Devonian platy mounds of NE British Columbia?

214