In the Lloydminster – North Battleford area the Cretaceous Mannville Group essentially comprises interbedded sands, shales and mudstones. These sediments exhibit a gentle overall dip toward the southwest and a thinning toward the south.
The Lloydminster – North Battleford area is the southeasterly portion of a belt in which Mannville sands contain huge quantities of bitumen and heavy crude. The first discovery of crude oil in Saskatchewan occurred in this area near Lloydminster, but progress here has been retarded due to the low demand for heavy oil. However, declining petroleum reserves, together with increased prices, has improved prospects for the exploitation of heavy oil accumulations generally.
Mannville oil-bearing strata lying outside administrative pool boundaries in the Lloydminster – North Battleford area are herein estimated to contain approximately 7.4 billion barrels of oil. The derivation of this volume is based upon the examination of electric logs. The reliability of this estimate of oil in place depends upon certain factors and assumptions inherent in its calculation.
The primary intent of this report is a general estimate of heavy oil in place in the most prospective sands of the Cretaceous Mannville Group of the Lloydminster – North Battleford area, Saskatchewan. A brief description of Mannville Group geology is also presented.
The study area encompasses Townships 44 to 54, Ranges 15 to 28 west of the Third Meridian plus Townships 38 to 43, Ranges 22 to 29 west of the Third Meridian (Fig. 1). However, areas lying within administrative pool boundaries are excluded from reserve estimates.
For this study the method employed involved mainly the examination of electrical logs of wells outside pool boundaries. Due to the paucity of cores and the poor quality of drill samples, along with the need to limit the time requirement, neither cores nor drill samples were examined. The accompanying description of geology is based upon log examination and the writers' previous experience with Mannville sediments.
Mannville sands near the city of Lloydminster yielded the first hydrocarbons produced in Saskatchewan. A commercial supply of gas was obtained from a well in Tp. 50, R. 28 W3 in 1934, and oil was discovered in 1935. This oil discovery occurred twenty-two years after drilling began in the first major Canadian oil field, namely Turner Valley (Sproule, 1968).
Early attempts to commercially produce the heavy crude from Mannville sands in the vicinity of Lloydminster failed. However, an increased price for fuel oil due to the Second World War revived interest in the recovery of this heavy oil. In 1944, the first commercial all production in Saskatchewan was obtained from a well in the Lloydminster area.
Since 1944, exploitation of the heavy oil sands in the west central part of Saskatchewan's sedimentary belt has proceeded gradually. The rate of development has been governed largely by market conditions and the price for heavy oil. By the end of 1975, a total of 1332 wells were producing oil in that portion of the province north of Township 37.