Chipewyan Granite— a building-stone prospect in Alberta

CIM Bulletin, Vol. 72, No. 805, 1979

JOHN D. GODFREY, Earth Sciences Branch, Alberta Research Council, Edmonton, Alberta

Geological mapping on the Canadian Shield in northeastern Alberta outlined several granitoid rock masses potentially suitable as building stone. A particularly attractive prospect, the Chipewyan Red Granite, was subjected to an aerial survey and ground check. The petrologic and fracture characteristics critical for quarrying and use as a building stone were assessed in the course of detailed mapping at two of the most favourable sites. The extension of good rock was tested to shallow depths at one site by shallow diamond-drill coring.The Chipewyan Red Granite displays a warm red colour, medium grain size and fairly massive texture, and takes a good polish. Deleterious geologic features studied in outcrop and subjected to structural analysis included regular joint systems, quartz veins, pegmatite dykes, basic shear zones and fault zones. Many of these key geologic features are systematic and hence predictable for stone quarrying purposes; other features, such as irregular fractures, are non-systematic and are far less predictable. The megascopic structural features studied show similar preferred orientations which appear to be collectively related to the tectonic history.

Mots Clés: Chipewyan Granite, Industrial minerals, Building stone, Alberta, Precambrian Shield, Lithology.