Growth in reserves from existing reservoirs has been the primary contributor to reserve additions in most mature basins. Historically, infill drilling has been the main driver for reserves growth for the Western Canadian Sedimentary Basin (WCSB) and other parts of the world. This study examines the other why's of reserve growth in WCSB. Examination of historical trends in fields shows that injection processes (Enhanced Oil Recovery, waterflooding) dominate reserves growth in WCSB, and have been the reason for an increasing oil rate in the region.
This paper will examine performance of both legacy production and infill well drilling programs and relate it to drive mechanism. Production trends in Canada will be presented as well as the incremental production and contribution to WCSB seen from the infill programs. Next, EOR development will be analyzed. Again, production trends in Canada will be presented and incremental oil contribution due to each individual EOR method will be shown. A brief look at USA EOR experience will also be analyzed. The influence of technology growth and oil price will be reviewed for both infill and EOR oil pools.