The Trout occurrence is located along a north east flowing tributary of Swanson Creek, approximately 8.8 kilometres south of the creeks' junction with the Nechako River.
The region is underlain dominantly by Lower to Middle Jurassic volcanic and sedimentary rocks of the Hazelton Group. These assemblages are overlain by the Upper Cretaceous to Lower Tertiary Ootsa Lake Group, the Cretaceous Kasalka Group and Miocene plateau basalt. Intruding Lower Jurassic rocks in the northeastern part of the map sheet is a belt of granodiorite, diorite, and quartz diorite plutons of the Lower Jurassic Topley intrusive suite. Felsic plutons of probable Cretaceous age intrude both Lower and Middle Jurassic Hazelton strata.
The Trout prospect is underlain dominantly by Upper Cretaceous to Lower Tertiary Ootsa Group (or possibly Kasalka Group) volcanics. These rocks consist of red to brown andesitic porphyry flows, tuff and breccias, intruded by porphyritic felsic dikes. Several wide, over 20 metres, dark greenish to grey feldspar porphyry dikes and a light-coloured rhyolite sill occur in the claim area. South of Swanson Creek more acidic (rhyolite, rhyodacite) ash flows and tuffs are located.
The Camp, Camp (North), the original Discovery and the Cap Zones all occur inside the south-western corner and along the southern edge of two parallel northeast trending fault structures forming the boundary of a 3-kilometre-long by 1.2 kilometre wide graben structure. The objective is to explore this structure to the northeast and test for epithermal precious metal mineralization at previously identified geochemical and geophysical targets inside and along the contacts of the graben boundary. Geological mapping suggests that gold and silver mineralization may either be ‘buried’ by a thin veneer of post mineral basalt rock or occur as near-surface silicified structures.
The Discovery or Main zone crops out southwest of Swanson Creek and south of the camp in a swampy valley bottom. The exposure is a northeast-trending ridge of rock, 50 metres long, 12 metres across and about 4 metres high. It consists mainly of pyroclastic breccia and overlying polymictic conglomerate of the Kasalka Group. The shallow southwest-dipping contact between the breccia and conglomerate acted as a conduit channelling mineralizing hydrothermal fluids. The hangingwall is flooded with silica and the footwall is pervasively silicified for about a metre below the contact.
At the Discovery zone, bonanza style gold and silver mineralization is hosted in banded chalcedony and quartz - adularia stockworks, veinlets and breccias, in and around semi rounded clasts of relatively unaltered and brecciated andesite and conglomerates. These clasts and fragments are commonly rimmed by banded chalcedony and quartz adularia mixes. Thin section descriptions of mineralized breccia samples from the Discovery zone confirm two stages of brecciation both containing small 'bead-like' grains of native gold and argentite, laminated chalcedonic quartz, adularia with quartz and lesser sericite.
Gold is found at two other areas known as the Camp and Camp North zones, located 150 metres northwest and 400 metres north of Discovery respectively. Gold and minor silver mineralization is hosted predominantly with silicified volcanic breccias, tuffs, conglomerates and clay altered zones. The volcanic rocks are rhyodacitic to trachytic in composition and are highly porphyritic. They are commonly but not always re-cemented or healed with pervasive silica, quartz veinlets and laminated silica and quartz and clay gouge. Disseminated pyrite is seen but is not overly abundant.
In the Camp (North) zone 2012 drill holes TR12-08 and 09 intercepted wide zones of low-grade gold mineralization associated with a quartz healed porphyritic trachyte breccia unit. The zone outcrops immediately below thin overburden, measures 300 metres by 200 metres in diameter and varies in thicknesses from 16 to 27 metres. It has a moderate resistivity IP signature and remains open in three directions. Grades average 0.2 to 0.5 gram per tonne gold and 1 to 5 grams per tonne silver (Assessment Report 34163).
The Discovery North zone is located approximately 1 kilometre north of the Discovery zone and comprises a silicified breccia with quartz-coated fragments. Quartz-calcite veining is also reported in sub-cropping lapilli tuff.
Work History
Precious metals were first discovered by Kerr Addison Mines Limited in 1984 when gold and silver values within a 60 by 300 metre zone were reported. Trench sampling on the Discovery zone averaged 19.5 grams per tonne gold over 5 metres of banded quartz-chalcedony-adularia veining and stockwork in polymictic conglomerate (Assessment Report 16539). This zone is bounded on the south by an east striking, 65 degree north dipping fault.
In 1985, Kerr Addison Mines Ltd. completed a program of rock and soil sampling, geological mapping, trenching, ground magnetic and induced polarization surveys and 11 diamond drill holes, totalling 1198 metres, on the Trout property. Drilling on the Discovery zone yielded intercepts including 6.70 and 3.45 grams per tonne gold with 190 and 35.0 grams per tonne silver over 0.8 and 8.9 metres, respectively, in hole TR-85-01 and 1.30 grams per tonne gold and 5.4 grams per tonne silver over 9.4 metres in hole TR-85-07 (Assessment Report 13973). Also at this time, trench sampling yielded up to 25.8 grams per tonne gold and 94.0 grams per tonne silver over 5 metres from trench no. 1 on the Discovery zone and 0.35 gram per tonne gold over 6 metres in trench no. 7 on the North zone (Assessment report 13973).
In 1987, Welcome North Mines Ltd. and Kerr Addison Mines Ltd. completed a program of rock and soil sampling, geological mapping, trenching and 13 rotary drill holes, totalling 767.0 metres, on the Trout property. Sampling of trench T-13 on the North zone yielded 0.68 gram per tonne gold over 14.0 metres, while a sample taken south of trench 1 on the Discovery zone assayed 8.21 grams per tonne gold over 7.0 metres (Assessment Report 15539). Also at this time, rotary drilling of the Discovery zone yielded intercepts of 2.48 and 1.36 grams per tonne gold over 35 and 53 metres, respectively, in hole 87-03 and 87-04, while a drill hole 87-12 on the Camp zone yielded 0.56 gram per tonne gold over 31 metres (Assessment Report 16733; Ostensoe, E.A. (2011-03-23): Technical Report – Trout Property).
In 1990, the property was optioned by Goldrite Resources and nine HQ holes (1050 metres) were completed on the Discovery and Camp zones. Drilling yielded intercepts of up to 0.79 gram per tonne gold over 13 metres in hole 90-04 (Ostensoe, E.A. (2011-03-23): Technical Report – Trout Property).
In 1992, Cogema Resources Inc. staked the ground and an airborne geophysical survey (VLF-EM, magnetics and resistivity) was flown in 1993. Eleven diamond drillholes totalling 1221 metres were completed in 1994. Drilling on the Discovery zone yielded up to 1.59 grams per tonne gold over 70.2 metres in hole 94-08 (Ostensoe, E.A. (2011-03-23): Technical Report – Trout Property).
In 1995, Phelps Dodge Corporation of Canada Ltd conducted a program of geological mapping, prospecting and rock sampling designed to explore for continuations of mineralization to the northeast and southwest of the Trout showing. Two bedrock samples (52472 and 56004) taken from a small felsite stock at the Camp North zone, yielded 1.40 and 1.56 grams per tonne gold with 5.8 and 3.9 grams per tonne silver, respectively, whereas a float sample (37768) from the Discovery zone yielded 2.74 grams per tonne gold and 62.7 grams per tonne silver (Assessment Report 24147).
In 1996, Phelps Dodge conducted geological mapping and re-logging drill core which provided a better understanding of the lithological and structural controls to mineralization in the Trout deposit. Bedrock samples collected along trend of the Discovery outcrop all contained anomalous concentrations of gold (122 to 15 880 parts per billion) and silver (1134 to 66435 parts per billion) over a total distance of 3.6 kilometres (Assessment Report 24833). Samples from the un-named north eastern zone yielded from 0.8 to 1.5 grams per tonne gold (Ostensoe, E.A. (2011-03-23): Technical Report – Trout Property).
Work in 1997 by Phelps Dodge consisted of 615.1 metres of diamond drilling in four holes to test for extensions of the Trout mineralization along dip of the altered breccia-conglomerate unit. The best intersection, DDH 97-3, returned 262 parts per billion gold over 26 metres, consistent with low-grade mineralization in the perimeter of the deposit (Assessment Report 25275).
In 2000, Robert Carmichael acquired the property over the following year completed a program of geological mapping and chip sampling of the “Rainbow” vein, an epithermal quartz vein located within the Discovery zone. Sampling of the vein yielded up to 43 grams per tonne gold and 298 grams per tonne silver over 0.25 metre (Ostensoe, E.A. (2011-03-23): Technical Report – Trout Property).
In 2004, Southern Rio Resources Ltd completed a total of 310.5 metres of diamond drilling in four holes. The results of the diamond drilling program show that the northeast trending, normal fault structure extends both downdip and along strike to the northeast from the Discovery Zone.
In 2010, an airborne magnetic survey was completed over the entire Trout gold-silver property, totalling 825 line-kilometres of magnetic and electromagnetic data. The survey identified several lineaments that trend northwest, north and northeast from the Discovery zone area (Assessment Report 32229).
In 2012, a diamond drill program was conducted on the property. Ten holes were drilled into four target areas within the boundaries of the graben feature for a total of 2019 metres. Highlights of results included drillhole TR12-05 assaying 0.33 gram per tonne gold over 47.8 metres from the Camp zone and drillhole TR12-09 assaying 0.44 gram per tonne gold over 16 metres from the Camp (North) zone located 425 metres northeast (Stockwatch, March 26, 2013). Venerable Ventures used a large track mounted excavator to complete a total of 211 metres of trenching across eight profiles in the Camp and Camp (North) areas. Significant results from the Camp zone include 21.1 metres grading 0.41 gram per tonne gold in trench TR-B and 16.0 metres grading 0.13 gram per tonne gold in trench TR-E (Assessment Report 34163).
In 2013, Goldbridge Holding Ltd. completed a program of geological mapping and structural analysis on the Trout property.
In 2014, Landmark Geological Inc. completed a program of prospecting, geological mapping, and soil sampling on the area. This work identified a number of target areas extending for several kilometres to the southeast of the Trout occurrence.
In 2015, Venerable Ventures Ltd. completed a program of soil sampling and an interpretation of previous airborne magnetic surveys. In 2018, a minor program of prospecting and rock sampling was completed. No assays were reported.
Refer to Stubb (093F 066) for further information on exploration in the area north of Knewstubb Lake by companies that held the Trout prospect at the same time, most notably Cogema and Phelps Dodge as the Cutoff property.