Abstract

Canada’s oil industry began at Oil Springs in southern Ontario with the successful completion by James Miller Williams in 1858 of North America’s first recorded oil well. By the turn of the century more than 2500 wells had been drilled in the area. From this beginning the search has continued to the present.

Natural gas was first discovered in commercial quantity in Essex County in 1889, followed rapidly by other discoveries. In the early 1900’s Ontario was an exporter of oil and natural gas but as demand grew has become an importer to the extent that local production supplies only a small percentage of requirements.

The sedimentary sequence in southwestern Ontario underlies a total area of some 41,000 square miles of which 15,000 square miles is covered by the waters of the Great Lakes. It reaches a maximum thickness of 4,800 feet and includes parts of the Michigan and Appalachian Basins separated by the Algonquin Arch.

A small sedimentary basin separated from southwestern Ontario by the Precambrian Frontenac Arch is known as the Ottawa Lowlands. It underlays 4,500 square miles of the province and reaches a thickness of 2,500 feet.

Sediments in southwestern Ontario vary in age from upper Cambrian to upper Devonian. In the Ottawa Lowlands, the upper Ordovician is the youngest paleozoic present.

Both source and reservoir beds are found in southwestern Ontario. Production has been obtained from beds representing all systems present. The Cambrian, the Gull River, Coboconk, Kirkfield, Cobourg and Sherman Fall of the Ordivician, the Whirlpool, Grimsby, Thorold, Irondequoit, Guelph, Salina A1 and A2 Units of the Silurian and the Dundee of the Devonian all produce gas while oil is produced from the Cambrian, Sherman Fall, Whirlpool, Grimsby, Guelph, Salina AI, Lucas and Dundee. The most prolific production is from the pinnacle reefs of the Guelph which are discussed in some detail.

Ontario’s proven oil and gas reserves as of December 31, 1970 have been established at 11.1 million barrels and 252.7 billion cubic feet respectively.

Potential reserves have been calculated using a statistical model. Areas of known reservoir characteristics were planimetered, reduced by the proven area, modified by a risk factor. Economically recoverable reserves are calculated by computer based on past drilling records, sizes of known fields and their reservoir characteristics. The final results are 4,086 trillion cubic feet of gas and 280.5 million barrels of oil approximately twice the C.P.A. estimated figures which are, however, based on a smaller sediment volume. Potential recovery factors are calculated for each unit and the results tabulated.

Adverse factors which influence or limit exploration for Ontario’s petroleum resources are discussed.

It is concluded that the industry in Ontario while small is likely to continue to be of interest to the small operator and thus remain active for years to come.