Sedimentology of McMurray Formation at HASDrive Site of AOSTRA Underground Test Facility, Northeastern Alberta, Canada
R. G. Chalcraft, J. H. Duerksen, W. R. Cox
The Lower Cretaceous McMurray Formation at the Alberta Oil Sands Technology and Research Authority (AOSTRA) underground test facility (UTF) site, HASDrive field trial area, is represented by a fining-upward sequence deposited during a marine transgression over Devonian limestone of the Waterways Formation. The clastic sediments were deposited in delta-plain, estuarine, tidal-flat, and shallow-marine environments as a gradual transgression proceeded over the existing basin.
Detailed core study, which included thin-section, SEM, size, chemical, and
conventional core analyses and palynological study, provided the data base for
interpretation at the UTF site. McMurray reservoir
sandstones, deposited as
distributary and tidal-channel sands, are normally well to moderately
well-sorted, subrounded to subangular, fine to very fine-grained subarkosic
arenites. Detrital mineralogy of the poorly consolidated McMurray sandstones is
dominated by quartz, feldspars, minor amounts of rock fragments, and mica. Clay
minerals, whether detrital or authigenic in origin, are present only in trace
amounts and therefore have a negligible effect on porosity and permeability.
Seven logged wells, four of which were cored, have been used to determine the
geometry of reservoir
sand bodies and intervening shale barriers in order to
provide a geologic model for
reservoir
simulation. The AOSTRA UTF site is being
used for a field trial of Chevron's Heated Annulus Steam
Drive
(HASDrive)
enhanced recovery process. In this process, heat is applied through a subsurface
horizontal pipe to basal bitumen-rich McMurray sandstone. A vertical steam
injection well aids in mobilization of the heavy crude and sweeps hydrocarbons
toward a horizontal subsurface producing well. HASDrive process performance is
evaluated through injection and production data, temperature and saturation
logging, well testing, and numerical modeling.
AAPG Search and Discovery Article #91022©1989 AAPG Annual Convention, April 23-26, 1989, San Antonio, Texas.