The geology of Torbrit Silver Mine lbBritish Columbia]

Torbrit Mine, which in 1956 was the third largest Ag producer in Canada, is located along the upper portion of the Kitsault River in the Portland Canal area of British Columbia. In the upper Kitsault River area the Hazelton group of rocks of Jurassic(?) age consists of 4 formations: Lower Sedimentary, Lower Volcanic, Upper Sedimentary, and Upper Volcanic. The rocks form a syncline that plunges at 30 degrees NW. The Hazelton group was intruded by feldspar porphyry in the late Cretaceous(?) and the entire assemblage was cut by andesite dikes in Tertiary(?) time. The Torbrit ore body occurs in the Lower Volcanic formation. It is a pod-shaped body plunging 30 degrees NW and lies on the NE end of a vein sheet that strikes N50 degrees E and dips 45 degrees NW and occupies a tension fracture; the ore body was formed in a horsetail-type shear zone. The gangue minerals are quartz and barite with jasper, calcite, and siderite. The main economic minerals are galena, tetrahedrite, pyrargyrite, argentite, and Ag, with variable quantities of pyrite, chalcopyrite, sphalerite, magnetite, and hematite.

This record provided courtesy of AGI/GeoRef.