Regional Reservoir Characterization and Exploration Assessment of the Late Devonian Jean Marie Formation, Northern British Columbia

The Late Devonian, Jean Marie Member of the Redknife Formation in northern British Columbia is an extensive carbonate shelf complex. Porous stromatoporoid boundstones are the primary reservoirs, and are stratigraphically trapped beneath and alongside the Upper Redknife Shale Member. This study focuses on characterizing porous reservoirs through detailed facies modeling, the mapping of key reservoir attributes, the delineation of diagenetic/ depositional controls on reservoir quality, and interpretation of the spatial distribution of facies within a sequence stratigraphic framework. The facies model and sequence stratigraphic framework for the Jean Marie Member are interpreted on the basis of detailed core description of whole core from 80 wells (1603 m of cumulative length), and wireline logs from 156 wells. The Jean Marie reservoir interval is composed of 17 facies grouped within 5 facies associations. Stromatoporoid boundstone (“reef”) facies associations are isolated as three distinct north-trending fairways within the eastern, central, and western portion of the study area. These fairways are interpreted to be the product of westward progradation and evolution of the carbonate succession from a ramp to rimmed shelf through time. The highest reservoir quality within the reef complex coincides with zones of grain-supported textures that are characterized by high interparticle porosity and abundant fractures. The spatial distribution of reservoir properties is depicted through maps of facies, grain supported textures, gross and net porosity, pore-volume, gross interval thickness and fracture density. These features may be used to evaluate geologic risk and guide future exploration within the area of study.

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