Understanding Complex Lower Mannville Deposits in the Western Canadian Sedimentary Basin by Integrating Geological and Geophysical Data
Understanding the stratigraphic architecture of geologically complex reservoirs, such as the heavy oil deposits of Western Canada, is essential to economically maximize hydrocarbon recovery. We integrated borehole and 3-D seismic data to define the stratigraphic architecture and generate a 3-dimensional geological model of the Mannville Group in West Central Saskatchewan. The study area corresponds to a stratigraphically controlled heavy oil reservoir with production from the undifferentiated Dina/Cummings members of the Lower Cretaceous Mannville Group. The seismic and well log data were combined to create an initial geological model. A multi-attribute analysis, employing neural networks, was then used to generate a pseudo-lithology (gamma ray) volume. The incorporation of borehole core data to the model and the subsequent integration with the lithological prediction were crucial to capture the distribution of reservoir and non-reservoir deposits in the study area. The ability to visualize the 3-D seismic data in a variety of ways, including arbitrary lines and stratal or horizon slicing techniques helped us to define stratigraphic features, such as channels, that affect fluid flow in hydrocarbon-producing areas. Unfortunately, small scale heterogeneities in the reservoir were not resolved due to the characteristics of the seismic data. Although not undertaken in out study, the resulting stratigraphic framework could be used to help construct a static reservoir model. Because of the small size of the 3-D seismic surveys, horizontal slices through the data volume generally imaged only small portions of the paleogeomorphologic features thought to be present in this area. As such, it was only through the integration of datasets that a coherent geological model of the field was established.
AAPG Search and Discovery Article #90090©2009 AAPG Annual Convention and Exhibition, Denver, Colorado, June 7-10, 2009