Abstract

The Northwest Territories, roughly one-third of Canada’s land area, were the last part of the country to attain significant mineral production. In spite of early discoveries of lead and zinc near Pine Point, petroleum at Norman Wells, cobalt bloom at Great Bear Lake, gold at Yellowknife, and nickel at Rankin Inlet, it was not until 1965, when production of lead and zinc in large quantities began at Pine Point, that the Northwest Territories became a major mineral producer. Current production from six areas, all in the District of Mackenzie, amounts to some $110,000,000 per year, about three per cent of Canada’s mineral production. The per capita production by the 40,000 people of the Territories (0.2% of Canada’s population) is relatively high.

In future, production of lead, zinc, gold, silver and tungsten can be expected to continue from the areas currently being exploited, with the addition of lead and zinc from Little Cornwallis and Baffin Islands and iron ore from Baffin Island.

Although climatic conditions severely restrict the economic potential of the northern third of Canada, it has been fashionable to make glowing predictions of the mineral potential of the region, mainly on the basis of its vast area, rather than an assessment of the geology. Exploration results have yet to come up to these expectations, although some important discoveries have been made.

At present, exploration activity is concentrated around operating and developing mines, and in four broad areas containing favourable rock types and a few important discoveries, namely: the northeastern portion of the Slave Structural Province, where important copper-lead-zinc-precious metal deposits have been discovered in the siliceous phases of Archean volcanic belts; the Rankin Inlet-Ennadai Belt where Archean rocks similar to those of the Abitibi orogenic belt have been outlined; the Proterozoic to lower Paleozoic carbonate shelf deposits lying along the northern part of the Arctic lowlands and southern edge of the Innuitian Region, where major lead-zinc deposits are under development; and the eastern portion of the Columbian Orogen of the Cordillera, where stratiform base-metal deposits occur in Proterozoic to lower Paleozoic shelf sediments, and epigenetic vein and replacement deposits appear to be related to Cretaceous intrusions.