Western Canada recorded a continuation of increased exploratory and development drilling during 1973. A total of 4,595 exploratory and development wells was drilled, an increase of 1,005 or 28.0% over 1972.

There were 196 oil and 561 gas discoveries for an exploratory-success ratio of 36.7%; 804 development wells were completed as oil producers and 1,094 as gas producers for a development-success ratio of 80.3%.

In Alberta an aggressive exploration play for shallow Cretaceous gas accounted for most of the gas discoveries in that province. In Saskatchewan, exploration was concentrated in the Lloydminster heavy-oil area, whereas in British Columbia exploration was mainly for gas, with at least 3 significant gas-bearing trends being discovered.

In the Arctic Islands, continued exploration by Panarctic and associates resulted in 3 additional gas discoveries. In the Mackenzie Delta, at least 3 gas discoveries were recorded, together with other probable gas discoveries and a probable oil discovery.

Geophysical activity declined in Alberta and adjacent provinces, but continued strongly in the Territories and Arctic Islands.

Production of liquid hydrocarbons, marketable gas, and sulfur was at an all-time high, but proved reserves of crude oil and natural gas liquids continued to show a slow decline because of lack of major discoveries. Although proved natural-gas reserves also showed a small decline, there is significant increase of probable reserves resulting from the many 1973 gas discoveries.