The Station M20 occurrence on the Tanzilla property is located just to the north of the headwaters area of the Tanzilla River and 30 kilometres southeast of the community of Dease Lake.
Most of the volcanic rocks observed in the Station M20 occurrence area consist of subaerial (weakly hematite stained) pyroclastic rocks ranging from lapilli tuffs to coarse debris flows, probably of Upper Triassic to Lower Jurassic age. Fragments range from lapilli size to 60 centimetres and are generally rounded and both monomictic and polymictic, depending upon location, typically with a fine-grained feldspar-phyric matrix. Dark green, fine-grained augite-phyric rocks, probably andesite flows, occur below the fragmental rocks and are more prominent in ranges forming the southern part of the property area. Locally, both fragmental volcanic rocks and andesite flow units appear to grade into hard, dark, very fine-grained massive units which might be hornfelsed units. On the eastern edge of the claims, dark green to black volcanic flows occur with coarse-grained, bladed feldspar phenocrysts. At lower elevations on many of the ridges it is common to find outcrops of pale grey, granodiorite of the Middle to Late Jurassic Snowdrift Creek pluton.
Chalcopyrite occurs in quartz stringers hosted in andesitic volcanics. A rock sample (B280972) analyzed 0.95 per cent copper and 9.7 grams per tonne silver (Assessment Report 28433).
A 2015 drill program tested for porphyry-style alteration and mineralization hypothesized to lie beneath and/or adjacent to a strongly altered lithocap exposed at surface on Silica Ridge zone (104I 142), and at the Gopher zone (104I 050) located 2.4 kilometres to the east of Silica Ridge. Drillhole TZ15-01 penetrated the lithocap and intersected over 500 metres of hypabyssal intrusive rock with varying degrees of porphyry-style alteration and mineralization. While TZ15-01 did not intersect economic mineralization, it provides proof of concept that the Silica Ridge lithocap is related to an underlying porphyry system. The system is open to depth, to the north, east, and southeast and requires more testing to determine alteration/mineralization vectors that would prove useful for locating one or more high-temperature cores to the system (Assessment Report 36431).
Two main types of mineralization were encountered during the 2015 drilling on the Silica Ridge zone: 1) Porphyry-style mineralization associated with zoned potassic and phyllic altered, quartz-saturated, porphyritic, intrusive and volcanic rock, and 2) High sulphidation-style mineralization associated with strongly intermediate to advanced argillic, or phyllic altered rock in a lithocap exposed at high elevation above the porphyry-style mineralization. Both styles of mineralization are responsible for strongly anomalous copper, with sometimes elevated gold, silver, zinc, and molybdenum. The porphyry-style mineralization was best observed in drillhole TZ15-01 on the Silica Ridge zone. Stockwork veining and fracture coatings are the main hosts to porphyry copper and molybdenum mineralization. Chalcopyrite and more rarely bornite are present in stockwork veining related to albitic, phyllic, potassic, or propylitic alteration. Chalcopyrite is the most abundant copper-bearing sulphide; it can be found in most types of veins, including chlorite/sericite plus pyrite, quartz, anhydrite, or composite veins. In some locations, low density chalcopyrite blebs are disseminated in altered rock. Where bornite is present it may be in association with chalcopyrite or independent. It typically occurs as very fine-grains or grain clusters in association with fine pyrite, within vugs or coating fractures; in some locations bornite forms a film on pyrite grains. Molybdenite occurs disseminated in, or as sub-millimetre bands within or along the edges of, pyrite plus sericite plus quartz veins. Dark brown to honey sphalerite is common in late quartz-rich composite veins and in anhydrite veins and clots, often in association with other sulphides (pyrite, chalcopyrite, and gray sulfosalts). Ghost veins overprinted by argillic alteration in the strongly altered lithocap may indicate that these alteration facies overprint earlier porphyry-style mineralization. A 22-metres intersection in drillhole TZ15-01 assayed 0.12 per cent copper (Assessment Report 36431).
High sulphidation-style mineralization was best observed between 72-236 metres in drillhole TZ15-01. It is associated with intense phyllic, intermediate and advanced argillic alteration, where the protolith is often unrecognizable. Copper-bearing minerals, in order of decreasing abundance include chalcocite, covellite, chalcopyrite, bornite, and possibly some copper-bearing sulphate minerals (brocanthite and chalcanthite). Chalcocite and covellite are by far the most abundant copper-bearing minerals. They frequently form bands of fine disseminated crystals in clay veins, and in clay-altered rock, sometimes with associated dumortierite. One-millimetre-scale euhedral chalcocite and/or covellite crystals often coat the edges of vugs. They commonly form a film, or overgrowth, on the abundant fine-grained pyrite that accompanies phyllic and argillic alteration. In a few locations, fine-grained chalcocite aggregates up to 15 millimetres diameter are present within the matrix of hydrothermal breccias. Chalcocite and covellite can be present in quartz veins that also host traces of chalcopyrite, molybdenite, and/or bornite. Where chalcopyrite is present it is often partly pseudomorphed by chalcocite (Assessment Report 36431).
In 2005, rock and stream sediment sampling was carried out on behalf of Western Keltic Mines Inc. and a total of 21 rock chip samples and 9 stream sediment and/or moss mat samples were collected. In 2006, on behalf of Cazador Resources, a program consisting of 1:5000-scale geological mapping and rock and talus-fines sampling was completed. Approximately 12 square kilometres of the central property area was mapped and structural controls on the silicification and alteration were defined.
The Tanzilla property was acquired in April 2011 by West Cirque Resources Ltd. and also covers the Tanzilla 1 (104I 022), Tanzilla 3 (104I 023), Thorn 75 (104I 102) and T-4 (104I 050) showings. In 2013, induced polarization, Terraspec, and structural surveys were conducted over the property. The Terraspec survey was undertaken to map the distribution of alteration minerals, particularly clay minerals, which can assist in defining zones of porphyry alteration and mineralization. The structural geology mapping program was conducted to identify structures that host porphyry-style alteration to assist in locating porphyry mineralization at depth. Two lines of induced polarization survey totalling 6.6 kilometres were conducted to further delineate the chargeability anomaly under Silica Ridge and to identify subsurface structure and resistivity signatures that might relate to zones of copper-gold porphyry mineralization.
In 2013, West Cirque Resources Ltd. signed an Earn-In Agreement with Freeport-McMoRan Corporation of Canada Limited to explore West Cirque’s Tanzilla and Pliny Properties. In June of 2014, West Cirque Resources Ltd. was acquired by Kaizen Discovery, and the option agreement with Freeport continued with Kaizen Discovery as the optionor. In 2014-15, Kaizen Discovery carried out a diamond drilling program totalling 3332 metres in eight holes. Seven holes were drilled on the Silica Ridge zone (104I 142) and one hole on the Gopher zone (104I 050).
