History of The Petroleum Industry in Canada - Leduc

Leduc

That changed in 1947, when Imperial Oil discovered light oil just south of Edmonton. Imperial's success was inspired by their much earlier discovery at Norman Wells in the Northwest Territories. The link was that there appeared to be Devonian reefs in Alberta. At the Norman Wells discovery, Imperial had located just such a reservoir in the 1920s.

During the 1930s and early 1940s, oil companies tried unsuccessfully to find replacement for declining Turner Valley reserves. According to legend, Imperial Oil had drilled 133 dry wells in Alberta and Saskatchewan, although the records show that many of those wells were natural gas discoveries that were uneconomic at the time.

In 1946, the company decided on one last drilling program from east to west in Alberta. The wells would be “wildcats” - exploratory wells drilled in search of new fields. The first drill site was Leduc No. 1 in a field on the farm of Mike Turta, 15 kilometres west of Leduc and about 50 kilometres south of Edmonton. Located on a weak seismic anomaly, the well was a rank wildcat. No drilling of any kind had taken place within an 80-kilometre radius.

Drilling started on November 20, 1946. It continued through a winter that was “bloody cold,” according to members of the rig crew. At first the crew thought the well was a gas discovery, but there were signs of something more. At 1,530 metres (5,020 ft), drilling sped up and the first bit samples showed free oil in dolomite, a good reservoir rock. After coring, oil flowed to the surface during a drill stem test at 1,544 metres (5,066 ft).

Imperial Oil decided to bring the well in with some fanfare at 10 o’clock in the morning of February 13, 1947. The company invited the mayor of Edmonton and other dignitaries. The night before the ceremony, however, swabbing equipment broke down. The crew laboured to repair it all night. But 10:00 a.m. passed and no oil flowed. Many of the invited guests left.

Finally by 4:00 pm the crew were able to get the well to flow. The chilled onlookers, now numbering only about 100, saw a spectacular column of smoke and fire beside the derrick as the crew flared the first gas and oil. Alberta mines minister N.E. Tanner turned the valve to start the oil flowing (at an initial rate of about 155 cubic metres per day), and the Canadian oil industry moved into the modern era. This well marked the discovery of what became the Leduc/Woodbend field, which has since produced about 50 million cubic metres (more than 300 million barrels) of oil.

Imperial lost no time. On February 12 the company had started drilling Leduc No. 2, about three kilometres southwest of No. 1, trying to extend the producing formation. But nothing showed up at that level and company officials argued over how to proceed. One group proposed abandoning the well, instead drilling a direct offset to No. 1; another group wanted to continue drilling No. 2 into a deep stratigraphic test. But drilling continued. On May 10 at 1,657 metres (5,436 ft), No. 2 struck the much bigger Devonian reef, which later turned out to be the most prolific geological formation in Alberta, the Leduc Formation.

Leduc No. 1 stopped producing in 1974 after the production of some 50,300 cubic metres (320,000 barrels) of oil and 9 million cubic metres (320 million cubic feet) of natural gas. On November 1, 1989, Esso Resources (the exploration and production arm of Imperial) began producing the field as a gas reservoir.