HOLLOWAY, DAVID C., Chevron Canada Resources, no location given
ABSTRACT: Geology at the Steepbank "In-Situ" HASDrive Pilot Site, Athabasca Tar Sands, Canada
The Athabasca tar sands of northeastern Alberta contain 13 trillion bbl of bitumen in place, 5% of which is accessible by surface mining techniques. If there is to be significant exploitation of the deeper buried resources, it will have to be done using subsurface "in-situ" technologies. Compared to surface mining, these methods are potentially more economic, can be developed on a smaller scale and are environmentally more sound.
The Lower Cretaceous McMurray Formation is by far the richest hydrocarbon bearing unit in Canada. Overall, it is a transgressive sand and mud dominated unit deposited in fluvial to marine environments. The main reservoir unit is an estuarine sand, whose complexity makes for an elusive exploration target and a challenging development project. Successful reservoir management of a subsurface "in-situ" operation depends on a solid understanding of estuarine stratigraphy and its lithologic heterogeneities.
For the past 20 years, Chevron has been developing an "in-situ" heavy oil extraction process called HASDrive (Heated Annulus Steam Drive). Recently, HASDrive and other technologies have been employed on a 77 sq mi lease with 9 billion bbl of heavy oil in place. The goal is to bring the lease to a fully commercial 10,000 bbl/day operation by 1997. In the exploration phase, 64 core hole wells were located with the aid of shallow 3-D seismic and electromagnetic techniques. The current pilot phase has utilized HASDrive to extract the bitumen from the sand and specialized seismic methods to monitor the development of the steam chamber.
AAPG Search and Discovery Article #90988©1993 AAPG/SVG International Congress and Exhibition, Caracas, Venezuela, March 14-17, 1993.