Geologic Framework, Reservoir Characterization and Production Analyses of the Cardium Formation: Unconventionally Developed North West Pembina Field, Alberta, Canada

Abstract

The unconventional Cardium Formation hydrocarbon reservoir in the Northwest Pembina Area of West Central Alberta transitions from offshore shales through lowest shoreface sandstones, which are unconformably overlain by conglomerate intervals. Within the sandstones and shales subsurface mapping reveals three cleaning upward parasequences. Thinning of the middle parasequence in the northeast direction is interpreted to indicate that both depositional and erosional processes controlled the northern field boundary. Comparisons of the reservoir interval in the west and east regions of the study area reveal significant variation in: reservoir lithology, quartz cementation, clay mineralogy and associated fluid sensitivity. Oil production from modern horizontal wells is documented to be dependent not only on reservoir quality and thickness, but also on well completion techniques. In locations where there are greater than 4 meters of reservoir, increasing the number of fractured stages is shown to have a significant impact on the first 20 months oil production.