Bringing Geoscience Back into the Reservoir Model: A Proposed Methodology for Predicting Heterogeneity within the Athabasca Oil Sands, Canada

The McMurray Formation in the Athabasca Oil Sands consists of a complex succession of unconsolidated sand and mud deposited in fluvial to marginal marine environments during the lower Cretaceous. Predicting the lithofacies in this reservoir is important for the optimization of reservoir delineation, horizontal well placement and field management.

Despite the large amount of well data available from the reservoir delineation phase of this field, lithofacies predictability away from well control remains uncertain. The use of 3D seismic attributes, in combination with well data allowed the creation of a lithofacies probability cube to constrain stochastic simulations of the reservoir model. However this was not sufficient to predict the reservoir heterogeneity. Wells and 3D seismic attributes were further used to define a cube of variogram parameters such as correlation ranges and azimuth to constrain the stochastic simulations of lithofacies even more. The methodology was then validated by comparing new well data to the lithofacies model.

AAPG Search and Discovery Article #90142 © 2012 AAPG Annual Convention and Exhibition, April 22-25, 2012, Long Beach, California