Development of the Turner Valley oil field continued with limited success through the 1920s and early 1930s until a very promising crude oil discovery was made in June 1936. Over the next five years, dozens of new wells were drilled into the newly-discovered, deep-producing zone. Existing refinery facilities proved inadequate to handle the rapid increase in crude oil production. The result was the immediate expansion of Imperial Oil's small Calgary refinery. Completion of the construction shown in this 1937 photograph made Calgary western Canada's most important petroleum refining centre.
The discovery's importance, in terms of Calgary's subsequent development, cannot be overemphasized. It changed the region immediately southwest of Calgary from an area of still uncertain potential into Canada's major producing oil field. From Calgary's new refinery complex came petroleum products to supply Western demand. With success in the Calgary area, local oil men were encouraged to expand their exploration activities to other parts of the province and, most important, this was made possible by the capital generated from Turner Valley production. In the process Calgary emerged as the management centre of the petroleum industry in western Canada. Thus, when the famed Leduc discovery was made in 1947, initiating a province-wide oil boom, Calgary's ascendancy was assured.
