Open File Report 1993-13

Open File Report 1993-13

OFR 1993-13

Southern Alberta Rift in Southwest Alberta

Southwest Alberta has had a long history of resource development as a result of coal mining, oil and natural gas development, forestry and other natural resource exploitation. The area is geologically complex and has diverse types of metallic mineral occurrences. Therefore, individual prospectors and the metallic mineral industry should consider southwestern Alberta as a prospective place to explore for a variety of metallic mineral deposits.

In 1992, a field program was conducted to search for and document features indicative of metallic mineral deposits that may be associated with the Southern Alberta Rift. This work was supplemented by a regional, reconnaissance, geochemical stream-sediment survey to provide a geochemical database to aid in mineral exploration, and to provide background data for resource assessment and environmental studies. The Southern Alberta Rift project area comprised all or parts of NTS areas 82G/ 7, 8, 9, 10, 15, 16 and 82J/1, 2, 7, 8. The project encompassed a total area of about 7,320 square km.

The results of the 1992 stream sediment and rock sampling, and of prior exploration from assessment records, indicated that intriguing geochemical anomalies exist in southwestern Alberta. Rock samples from newly discovered metallic mineral occurrences assayed up to 227 parts per million copper, 184 parts per million lead, 798 parts per million zinc and 0.7 parts per million silver, with elevated concentrations of arsenic, barium, cadmium and molybdenum.

Stream sediment samples assayed up to 99 parts per billion gold and 0.8 parts per million silver, 51 parts per million copper, 29 parts per million lead, 213 parts per million zinc, with anomalous concentrations of other elements such as antimony, arsenic, barium, cadmium, cobalt, mercury, molybdenum, nickel and uranium.

Rock samples from known metallic mineral prospects and occurrences assayed up to 3.48% copper, 12.1% lead, 19.5% zinc and 118.6 parts per million silver. The available records of prior exploration indicate that there has not been a large amount of systematic, detailed exploration in the Proterozoic and Phanerozoic rocks of southwestern Alberta. This, coupled with the results of the 1992 Southern Alberta Rift program, indicates that the potential for discovery of important metallic mineral deposits in southwestern Alberta is good.