The Bear occurrence is located on a generally north-south–trending ridge near the north end of a south-southeast–trending valley, northwest of the South Gataga Lakes.
The area is underlain by calcareous black shale, dolomite and ankeritic siltstone of the Ordovician to Devonian Road River Group, Lower Devonian chert-pebble conglomerate of and siliceous and carbonaceous black shale of the Upper Devonian Gunsteel Formation (Earn Group).
The mineralization, traced for 1.5 kilometres along strike and intersected over 200 metres below the surface, is hosted within siliceous shales of the Gunsteel Formation. The mineralization is conformable with the bedding, which strikes 155 degrees and dips 80 degrees west. Diamond drilling has defined an upper and lower zone of massive mineralization, separated by 2 to 8 metres of barren shale. The upper zone, 60 to 25 metres in width, comprises finely crystalline, bedded barite with interstitial galena and sphalerite overlying non-baritic, finely laminated, massive pyrite with interstitial and bedded galena and sphalerite. The massive sulphide mineralization assayed 34.3 grams per tonne silver, 2.45 per cent zinc and 0.56 per cent lead over 6.9 metres (true thickness; Assessment Report 8626, drill log 80B-1). To the southeast, this body grades into a mega-breccia slump body, with deformed bedded barite and pyrite clasts in a very fine-grained barite, pyrite and chert matrix.
In the hangingwall of the upper zone, mineralization occurs as sporadic, 1- to 2-centimetre interbeds and veins of galena, barite and sphalerite hosted within black carbonaceous chert. A 17.1-metre drill intersection (11.1 metres true thickness) of this mineralization graded 1.91 per cent combined lead-zinc and 15.7 grams per tonne silver (Assessment Report 8626, Drill log 80b-4).
The lower zone, comprising non-baritic, massive pyrite with galena and sphalerite, graded 1.35 per cent combined lead-zinc and 7.7 grams per tonne silver (Assessment Report 8626).
In 1993, a chip sample (37767) from a trench on the Central Bear occurrence assayed 10.4 grams per tonne silver over 5 metres, while two samples (37755 and 37621) from zones of ferricrete yielded 0.93 and greater than 1.00 per cent zinc, respectively (Assessment Report 23308).
In 1994, drilling on the northwest strike extension of the Bear occurrence yielded intercepts of up to 5.28 per cent zinc, 0.11 per cent lead and 1.6 grams per tonne silver over 6.0 metres (151.2 to 157.2 metres down-hole) in hole B-14 (Assessment Report 23820).
Work History
In 1970, Geophoto Surveys conducted a reconnaissance stream sediment survey in the region. In 1973/1974, Canex-Placer investigated stream sediment anomalies with initial prospecting and discovered mineralized float in Driftpile Creek, which was later staked. In 1974/1975, Canex-Placer conducted geological mapping, soil sampling, hand trenching and an electromagnetic survey in the Driftpile area. In 1976, Castlemaine conducted further stream sediment sampling in the region around the Canex-Placer property.
The Bear showings were discovered in 1977 by the Gataga Joint Venture, which was organized by Aquitaine Company of Canada Ltd., Chevron Canada Limited, Getty Mining Pacific, Limited and Welcome North Mines Ltd. The Gataga Joint Venture was formed to follow up extensive anomalies on unstaked ground. Work consisted of extensive soil sampling and regional geological mapping. During this phase, the Bear claim was staked to cover anomalies over a weakly mineralized zone, which was hand trenched. Drilling is also reported to have been done.
In 1977, Welcome North Mines Ltd. completed a program of geological mapping, trenching and geochemical (soil and water) sampling on the area as part of the Bob, Pig, Saint and Sol claims of the Gataga Joint Venture property.
In 1979, the SI claims were added to protect favourable stratigraphy with soil anomalies. The IF claims were also staked in 1979 to cover a possible strike extension of the Bear mineralization. In 1980, the main showing on the Bear claim was tested by the Gataga Joint Venture with five diamond drill holes, totalling of 818 metres. In 1981, two diamond drill holes, totalling 325.5 metres, and a program of soil sampling tested mineralization on the Bear property. In 1982, a program of soil and silt sampling was completed on the IF and Boffo claims.
In 1993, two weeks of mapping and sampling by Teck Exploration Ltd resulted in the collection of 44 rock samples. In 1994, a total of eight NQ diamond drill holes, totalling 1808 metres, were completed. Only two of these holes were reported on by Teck Exploration Ltd. Drilling confirmed that mineralization remains open to the northwest. A recognizable sequence of rock types hosting mineralization is recognized and appears overturned in the area of the 1994 drilling. The sequence consists of a basal footwall sequence of graphitic cherts with varying amounts of pyrite disseminations and laminations. The main mineralized zone occurs at the break into non-siliceous shales and turbidites. This 15- to 20-metre thick interval consists of well-laminated pyrite and barite (SEDEX-style) mineralization with varying amounts of laminated sphalerite and galena and was considered to be sub-economic. The upper part of the sequence encountered in the lower portions of the holes consists of non-siliceous shales and turbidites. Mineralization is open both along strike and downdip and further drilling is warranted. The most promising direction appears to be downdip, away from dissecting thrust faults.
In 2013, Teck Resources Limited completed a 23.4 line-kilometre airborne magnetic and electromagnetic (VTEM) survey on the area immediately north of the occurrence as the SI property.
