Stratigraphic Architecture and Cyclic Sedimentary Record in Point Bar Deposits: Implications for Reservoir Characterization and Heterogeneity Prediction, Cretaceous McMurray Formation, Alberta.

摘要

Sandstone-dominated point bar deposits in the McMurray Formation (in the Athabasca Oil Sands) account for a significant proportion of subsurface reservoirs. In-situ production techniques require an accurate geological model of the reservoir, including the distribution of siltstone interbeds that can increase heterogeneity and affect bitumen recovery. The objectives of this study are to construct a sedimentological model of a point bar deposit, and to qualitatively and quantitatively assess the spatial distribution of impermeable siltstone beds in the succession.;The dimensions of the channel studied are constrained by seismic data, cores and wireline logs. Logging of core coupled with statistical analyses of wireline logs using correlograms, Fourier transforms and wavelet transforms, demonstrate that siltstone is distributed cyclically throughout the reservoir at wavelengths of 2-10 m. Therefore, validating the strength and location of depositional cyclicity provides some predictability in a complex reservoir system and allows for more accurate reservoir modeling.