The Moffat occurrences are in the headwaters of Tenquille Creek, approximately 25 kilometres north of Pemberton. The Eva workings are exposed at an elevation of approximately 1850 metres, whereas the Grizzly shear is exposed to the north west at an elevation of approximately 1926 metres.
Regionally, the area lies in a north west-trending belt of volcano-sedimentary rocks assigned to the Upper Triassic Cadwallader Group and lower to middle Jurassic Ladner Group, which represents an island arc assemblage with reported occurrences of felsic volcanic rocks. These have been intruded by dioritic and granodioritic rocks of the Jurassic to Cretaceous Coast Plutonic Complex.
Locally, at the Moffat prospect area, strata of the Cadwallader Group are northwest- trending, northeast- dipping, right-side-up, calc-alkaline volcanic rocks. The volcanic assemblage is intruded by a Cretaceous diorite to quartz diorite pluton. Tertiary basalt flows with minor rhyolite overlie the Cadwallader Group to the northwest. Four stratigraphic units have been identified in the Cadwallader Group at the Moffat prospect. From oldest to youngest these are: massive andesite and andesite breccia, mixed andesite to dacite pyroclastics, quartz feldspar porphyry pyroclastics and dacite to rhyodacite quartz feldspar porphyry flows. Mixed pyroclastics are composed of dark- green andesitic tuffs and dacitic lithic lapilli ash tuff and lesser breccia. Black shale, pale- green mudstone, black to grey siltstone, black and green phyllite, white chert and feldspar-rich volcanic greywacke with minor conglomerate comprise minor sedimentary interbeds. Andesite and pyroclastics are altered to siliceous sericite schist and appear to be associated with the Grizzly fault zone. The porphyry dikes are probably related to the Jurassic to Cretaceous Coast Plutonic Complex, which lies to the west.
A major northwest- trending fault, the Grizzly shear zone, bisects the Moffat prospect. The fault is composed of a complex set of anastomosing northwest shears. The Grizzly shear zone is thought to be a regional fault more than 100 kilometres long. Foliations in the main part of the Grizzly shear zone strike west-northwest to northwest. Dips are moderately west.
Mineralization has been discovered at several zones on the Moffat prospect, including the Eva, Grizzly shear, Cliff, Shale contacts and New.
The ‘Eva’ zone constitutes the original discovery at the Moffat prospect and consists of a 1-metre wide surface outcrop that has been explored by a 3-metre deep vertical shaft, two adits, and several pits or trenches. Mineralization consists of chalcopyrite and minor pyrite, sphalerite and bornite with quartz blebs and chlorite. The mineralization occurs in a 3-metre wide, silicified pyritic zone hosted in a larger sericite- altered zone in a thin quartz feldspar porphyry flow or sill. In the shaft, irregular pyrite and chalcopyrite veinlets cut a rusty chloritic rock with quartz blebs. In a caved adit, 30 metres below the shaft, narrow bands of quartz sericite schist with pyrite and chalcopyrite were reported. The Lower Creek adit, along Grizzly Creek, was driven in the 1920’s to intersect the Eva zone at an elevation 213 metres lower. Pyritic quartz sericite schists are exposed at the portal.
In 1985, samples from a contact zone assayed trace gold and 68.6 grams per tonne silver, 1 per cent copper, 6.1 per cent lead and 12.1 per cent zinc (Assessment Report 14708).
In 1990, sampling of a 1- metre wide mineralized knob yielded 5.60 per cent copper, 0.16 per cent zinc, 88.3 grams per tonne silver and trace gold, whereas sampling of the 1.5-metre wide silicified footwall and 0.5-metre wide hangingwall yielded up to 0.14 per cent copper and 8.7 grams per tonne silver (Assessment Report 21272). The weighted average over 3 metres was 2.88 per cent copper, 0.09 per cent zinc and 44.4 grams per tonne silver (Assessment Report 21272). A sample from the Lower Creek adit dump yielded 0.07 per cent copper, 0.13 per cent zinc, 9.89 grams per tonne silver and 0.02 per cent arsenic, whereas four samples from an ore stockpile by the shaft averaged 5.87 per cent copper, 0.22 per cent zinc, 81.3 grams per tonne silver and 0.09 gram per tonne gold (Assessment Report 21272).
The ‘Grizzly shear’ zone contains more zinc-rich mineralization associated with quartz sericite schists. The Canyon and Creek adits exposed this type of mineralization along Grizzly Creek. The 5-metre long Canyon adit contains pyrite, sphalerite with minor chalcopyrite and galena mineralization within a 1-metre wide silicified zone hosted in pyritic quartz sericite schists. The schists appear to have originated from felsic crystal tuffs. This zone has been traced for 300 metres. The 35-metre long Creek adit was excavated in the 1920’s to intersect a 1.5-metre wide pyritic silicified zone exposed in an open-cut northwest of the Creek adit. The siliceous zone is hosted by pyritic quartz sericite schist and carries sphalerite with minor galena. Chalcopyrite mineralization is hosted by quartz sweats in the vicinity. Bands of sphalerite mineralization can be traced for 200 metres along the creek. Mineralized quartz sweats exposed within pyritic quartz sericite schists along the Grizzly shear zone, 1.0 to 1.8 kilometres northwest of the Canyon adit, are additional evidence for remobilization. At the north west end of the Grizzly grid, talus boulders below a steep outcrop (Cliff zone) host chalcopyrite, pyrrhotite and pyrite with minor sphalerite in a massive andesite.
In 1990, a grab sample from the Canyon adit assayed 4.0 per cent copper, 0.7 per cent lead, 9.0 per cent zinc, 20.0 grams per tonne silver and 0.1 gram per tonne gold, while pre-1990 chip sampling from the Canyon adit yielded up to 1.02 per cent copper, 1.14 per cent lead, 6.60 per cent zinc, 26.06 grams per tonne silver and 0.17 gram per tonne gold (Assessment Report 21272). A grab sample of pyritic quartz sericite schist from the Creek adit yielded 0.06 per cent copper, 0.10 per cent lead, 0.37 per cent zinc, 12.6 grams per tonne silver and 0.25 gram per tonne gold (Assessment Report 21272). Also, at this time samples of talus boulders from the ‘Cliff’ zone yielded 4 per cent copper, 0.126 per cent zinc and 48 grams per tonne silver (Property File - Teck Corp. [1990-12-01]: 1990 In-House Report - Geological, Geochemical, Geophysical Report on the Avalanche Property).
In 1992, a diamond drill hole (AV92-7) yielded 0.11 per cent copper, 0.64 per cent lead, 3.02 per cent zinc and 2.4 grams per tonne silver over 0.5 metre proximal to the Grizzly shear (Property File - Teck Exploration Ltd. [1992-12-01]: 1992 In-House Diamond Drill Report on the Avalanche Property).
In 1991, two base-metal enriched horizons, referred to the as the ‘Upper’ and ‘Lower’ horizons and located west and east of the Grizzly shear, respectively, were identified by drilling. The horizons occur at specific stratigraphic intervals, approximately 80 metres apart, and are characterized by high pyrite content with associated base metal values. The ‘Upper’ horizon is hosted in a quartz eye pyroclastic unit between the quartz-feldspar porphyry flow and mixed pyroclastic units, while the ‘Lower’ horizon is associated with an interbedded chert within the mixed pyroclastic unit.
In 1991, diamond drilling yielded up to 0.75 per cent zinc over 17 metres from the ‘Lower’ horizon and 0.2 per cent zinc over 12 metres; including 0.3 per cent zinc over 6 metres from the ‘Upper’ horizon (Property File - Teck Exploration Ltd. [1992-12-01]: 1992 In-House Diamond Drill Report on the Avalanche Property). The following year, diamond drilling on the ‘Lower’ horizon yielded up to 0.114 per cent zinc over 2.0 metres, while the ’Upper’ horizon yielded 0.19 per cent copper, 0.30 per cent lead, 1.41 per cent zinc and 3.9 grams per tonne silver over 0.5 metre and 0.18 per cent zinc over 12.6 metres (Property File - Teck Exploration Ltd. [1992-12-01]: 1992 In-House Diamond Drill Report on the Avalanche Property).
Similar but less extensive mineralization than the Eva zone is exposed at several locations, referred to as the ‘Shale contact’ zones, which are located up to 1.5 kilometres northwest of the Eva. The mineralization of the Shale contacts consists of pyrite, chalcopyrite and malachite hosted by silicified and sericite- altered quartz feldspar porphyry sills and/or dikes at shale contacts. In 1990, samples of mineralized quartz feldspar porphyry sills at the Shale contacts yielded up to 1.5 per cent copper, 0.3 per cent lead, 0.07 per cent zinc and 13.8 grams per tonne silver (Assessment Report 21272).
Another zone of mineralization consists of pyrite, chalcopyrite and minor sphalerite hosted by silicified zones and quartz sweats, up to 50 centimetres wide, within dacitic lapilli tuff and tuff-breccia. Less than 100 metres east of this zone, mudstone or fine dacite ash tuff proximal to quartz feldspar porphyry sills hosts pyrite and pyrrhotite mineralization with silica and chlorite alteration. In 1990, sampling of the first zone yielded up to 0.677 per cent copper, 0.170 per cent zinc, 7.4 grams per tonne silver and 0.11 gram per tonne gold, while sampling of the quartz sweats yielded up to 1.5 per cent copper, 0.3 per cent zinc and 41.4 grams per tonne silver over 30 centimetres (Property File - Teck Corp. [1990-12-01]: 1990 In-House Report - Geological, Geochemical, Geophysical Report on the Avalanche Property). Sampling of the eastern zone yielded up to 0.261 per cent copper, 4.7 grams per tonne silver and 0.05 gram per tonne gold over 0.5 to 1.0 metre (Property File - Teck Corp. [1990-12-01]: 1990 In-House Report - Geological, Geochemical, Geophysical Report on the Avalanche Property).
The ‘New’ zone, identified in 1992, consists of a 35-centimetre wide calcite vein with massive pyrite, sphalerite and chalcopyrite in a sericite and chlorite altered host. The zone is exposed by a previously undocumented 3-metre-deep shaft and trends 140 to 145 degrees with a dip of 70 to 80 degrees to the south west. The mineralization has been traced, intermittently, for approximately 100 metres to the south east of the shaft by trenches and open-cuts. In 1992, sampling of the shaft (no. 11101) assayed up to 33 per cent zinc, 6 per cent copper and 25 grams per tonne silver over 35 centimetres, while two drill holes (AV92-2 and AV92-3) yielded intercepts of 1.57 and 1.3 per cent zinc, 0.19 and 0.25 per cent copper and 1.6 grams per tonne silver over 0.5 metre, respectively (Property File - Teck Exploration Ltd. [1992-12-01]: 1992 In-House Diamond Drill Report on the Avalanche Property).
The occurrence was originally discovered in the early 1920’s by G. Moffat. At this time, the property consisted of the Moffat and later the Eva claims. From 1922 to 1926, five adits, several pits and trenches were excavated. In 1952, National Consolidated Base Metals Company examined the area. In 1961, Phelps Dodge completed a program of geological mapping on the area as the Tenquille claims. In 1984 and 1985, Caliente Resources Ltd. acquired the property and conducted geological mapping, and soil, magnetic and electromagnetic surveys. In 1990, Teck Corporation optioned the property from Caliente Resources (now Toscana Resources). Further geological mapping, diamond drilling and soil and geophysical surveys were conducted for volcanogenic massive sulphide targets in 1991. In 1992, Teck completed eight diamond drill holes, totalling 1419 metres. In 2003, the area was staked as the Gold King property by J.T. Shearer. During 2004 through 2006, Goldking Mining Ltd. (later Wolverine Minerals Corp.) completed programs of rock and soil sampling, geological mapping and an induced polarization survey on the area.