The Gataga 19 copper occurrence is located on a creek, approximately 9 kilometres north of the Gataga River and 9.5 kilometres west-southwest of Churchill Peak in the mountainous Muskwa Ranges of the Northern Rocky Mountains (Assessment Report 2639, Map 1).
The occurrence is in a region known as the Muskwa Anticlinorium, a major north-northwest–trending structure characterized by thrust faults and moderate folding. Rocks as old as Middle Proterozoic (Helikian) outcrop in the structure, along with Paleozoic rocks (Geological Survey of Canada Map 1343A; Geological Society of America, Geology of North America, Volume G-2, page 639). All belong to Ancestral North America (Geological Survey of Canada Map 1713A). The Middle Proterozoic rocks are pre-Windermere Supergroup and are known as the Muskwa Assemblage (Geological Society of America, Geology of North America, Volume G-2, page 111). Proterozoic diabase or gabbroic dikes are common in the region.
The Gataga claim group is underlain by the Aida and Gataga formations of the Muskwa Assemblage (Geological Survey of Canada Memoir 373, Paper 67-68; Assessment Report 2639). The Aida Formation consists of interbedded dolomitic siltstone, argillaceous limestone, slate and argillite. The Gataga Formation comprises thinly bedded slate and slaty mudstone and siltstone. The strata strike north-northwest and dip gently to moderately west. Slaty cleavage dips westwards more steeply than bedding. Subhorizontal, unconformably overlying dolostone and quartzite of the Cambrian Atan Group lie at the southwestern extremity of the claim group.
A number of diabase dikes intrude the Proterozoic rocks. They dip steeply westwards and generally strike northwest, though some strike north or northeast. Some contact metamorphism is present. Faults and shear zones in the area have similar attitudes to the dikes, and many occur along dike margins.
The Gataga 19 occurrence is centred on Showing No. 1 (Assessment Report 2639), also called the Gataga South zone (Geology, Exploration and Mining in British Columbia 1971). A small area of quartz-carbonate veining within or marginal to a diabase dike is associated with a northwest-trending fault zone along a creek in the south of the claim group. The veins are parallel to the fault zone, dipping approximately 65 degrees southwest. They have a strike length of 60 metres and range in width from 15 to 60 centimetres. The veins contain chalcopyrite in discontinuous blebs or massive lenses up to 30 centimetres wide, concentrated in the centre, with malachite in the peripheral zones. Mineralization is moderate to low-grade (Geology, Exploration and Mining in British Columbia 1971). Subsidiary shear fractures contain calcite and pyrite veinlets.
In 2005, chip sample (B374221) from a quartz-carbonate vein with pyrite, chalcopyrite and malachite, located on the hangingwall of a diabase dike, assayed 9.1 per cent copper over 0.25 metre (Assessment Report 28281).
Work History
In 1970, Windermere Exploration Ltd. completed a program of geological mapping, hand trenching and rock sampling on the area as the Bronson and Gataga claim groups.
In 1981 and 1982, Coppex Syndicate completed a program of geological mapping and geochemical (rock and soil) sampling on the area as the BE and MO claim groups.
In 2005, Twenty-Seven Capital Corp. completed a regionally extensive program of geochemical (rock, silt and soil) sampling and a 9002.0 line-kilometre airborne magnetic survey on the area as the Muskwa property.
In 2012, a remote sensing and geophysical data interpretation program was completed on the area as part of the regionally extensive Northern IOCG property.
