The Ketchan Lake North (Log) occurrence is located approximately 400 metres east of Ketchan (Duke) Lake, 2.25 kilometres southwest of Missezula Lake and 35.5 kilometres north of Princeton.
The region southwest of Missezula Lake is underlain by the Eastern volcanic facies of the Upper Triassic Nicola Group, comprising mafic to intermediate augite and hornblende porphyritic pyroclastics and flows, and associated alkaline intrusions. The intrusions vary in composition from diorite to monzonite and are thought to be comagmatic with the Nicola Group, ranging in age from Upper Triassic to Lower Jurassic. Much of the copper mineralization and associated alteration frequenting this portion of the Nicola belt can be attributed to the emplacement of such intrusions.
Locally, the area is underlain by northwest-striking, moderately northeast-dipping andesitic flows, with lesser andesitic lapilli and crystal tuffs and minor lahar deposits of the Nicola Group (Central Belt, Bulletin 69). This sequence is intruded by a west-trending mass of fine- to medium-grained diorite (microdiorite), roughly centred about Ketchan Lake and measuring 4000 by 2000 metres. The diorite commonly contains seams and irregular replacements of orthoclase. Epidote is widespread, and is frequently developed along northwest-striking, northeast-dipping fractures. Disseminations and veinlets of magnetite are also present in this stock.
The occurrence is hosted in a 2-kilometre-long, multiphase diorite to monzodiorite intrusion, referred to as the Ketchan stock, that has undergone widespread brecciation and extensive magnetite, epidote and potassium feldspar alteration. Mineralization consists of pyrite and chalcopyrite, usually as disseminations, but also as fracture fillings, associated with magnetite veins and breccia matrix and variable amounts of epidote, potassium feldspar, actinolite, chlorite, sericite and carbonate alteration. Rare bornite and chalcocite are also reported. Some malachite is also present in surface exposures.
Trenching and drilling, up to 2015, has intersected copper mineralization in a northwest-trending zone over a strike length of 1560 metres, 300 to 500 metres wide, up to 236 metres depth and roughly paralleling the northeastern margin of the stock. The mineralized zone is reported to be open to the northwest, southeast and at depth.
Work History
This occurrence was first staked by Plateau Metals Ltd. in 1962, after copper mineralization was uncovered during a logging operation. The company completed programs of soil sampling, a magnetometer survey and drilled seven holes, totalling 513.5 metres, later that year. Surface sampling of a granitized breccia with disseminated chalcopyrite is reported to have yielded up to 1.56 per cent copper over 3.6 metres, whereas a trench approximately 60 metres to the south exposed an oxidized gossanous zone yielding 0.17 per cent copper and 8.2 grams per tonne silver over 28.5 metres (Assessment Report 977). Also at this time, a hole (P3) drilled in the vicinity of a gossan near the north end of the mineralized zone yielded 0.22 per cent copper over 39.6 metres, whereas sludge and core samples from holes P1(a) and P2, located to the southwest of the previous hole, yielded 0.21 and 0.44 per cent copper over 16.5 and 3.9 metres, respectively (Assessment Report 977).
In 1966, an additional seven holes, totalling 512 metres, were drilled on the Strike-Lorna group of claims after the property was optioned to Adera Mining Ltd. Various geophysical and geological surveys and 768 metres of trenching were also completed in 1966. A channel sample of hard, well-fractured, silicified diorite containing evenly disseminated fine crystals of chalcopyrite yielded 1.36 per cent copper over 3.05 metres (National Mineral Inventory). A section of gossan near the north end of the zone assayed 0.17 per cent copper and 8.23 grams per tonne silver over 29 metres (Assessment Report 977). Also at this time, drilling yielded intercepts including 0.42 and 0.24 per cent copper over 3.0 and 9.0 metres, respectively, in holes A3 and A4 (Assessment Report 977). These holes were located approximately 1.1 and 0.5 kilometres southwest of the previous drillholes and trenches.
In 1971, Adera Mining Ltd. completed a soil sampling program on the claims. The area was re-staked by Bethlehem Copper Corporation in 1973 as the Log claims. The company completed programs of geological mapping, sampling and 10 percussion drill holes, totalling 901.0 metres, 4 diamond drill holes, totalling 351.0 metres, and one rotary hole, totalling 218 metres, in 1974 and 1975. Rotary drilling near the centre of the zone intersected disseminated chalcopyrite to a depth of 218 metres (Assessment Report 5824). No assays were reported. Later reports (circa 1992) indicated that four of the drillholes intercepted copper mineralization grading 0.1 to 0.2 per cent copper over 42 to 117 metre intervals, including 0.4 to 0.5 per cent copper over 9 to 24 metre intervals (Assessment Report 21746).
In 1979, a further two diamond drill holes, totalling 410.0 metres, and 38.8 line-kilometres of induced polarization surveys were completed on the Log claims. The drillholes were located on geophysical anomalies and no significant drilling intercepts were reported.
In 1987, Cominco Ltd. completed a program of soil sampling on the area as the Log 1-4 claims. In 1991, Cominco Ltd. completed 1067.3 metres of percussion drilling in 15 holes. Three diamond drill holes (B-10, B-12 and B-13), centred approximately 750 metres south-southeast of the (1962) hole P3 assayed 0.379, 0.240 and 0.133 per cent copper with 0.076, 0.082 and 0.106 gram per tonne gold over 86.6, 80.5 and 90.6 metres, respectively, whereas another hole (B-14), located approximately 400 metres southeast of the previous holes, yielded 0.112 per cent copper over 42.3 metres (Assessment Report 21746).
In 1992, Cominco Ltd. conducted a further program of soil sampling and eight percussion drill holes, totalling 640 metres. Highlights include drillhole M92-4, which returned 81.4 metres grading 0.260 per cent copper and 0.124 grams per tonne gold, and hole M92-6, which yielded 0.156 per cent copper and 0.155 gram per tonne gold over 89.1 metres (Assessment Report 22555).
In 2002, Gary Brown completed a 26.0 line-kilometre ground magnetic survey on the area as the Ketchan claims. In 2004, William Richard Bergey completed reconnaissance geological mapping on the Aspen Grove property. Also at this time, Copper Hill Exploration Corp. completed a program of geological mapping on the area as the Ketchan property.
In 2005, Copper Belt Resources Ltd. conducted geological mapping and a 10-hole diamond drill program totalling 1210.2 metres on the area as the Ketchan Lake property. Highlights include drillhole K05-04, which yielded 0.38 per cent copper and 0.10 gram per tonne gold over 100.7 metres (9.2 to 109.8 metres down hole), whereas the nearby drillhole K05-07 intersected a 35.8-metre section (50.3 to 86.0 metres down hole) that assayed 0.54 per cent copper and 0.19 grams per tonne gold (Assessment Report 28484). Also at this time, a drillhole (K05-08) tested the depth potential of the occurrence and yielded 0.34 and 0.46 per cent copper with 0.09 and 0.36 gram per tonne gold over 88.5 and 19.3 metres (9.8 to 98.2 and 217.0 to 236.3 metres down hole), respectively (Assessment Report 28484).
In 2006 and 2007, Midland Resources Corp. completed 1416 metres of diamond drilling in seven holes. Highlights include drillhole K-06-11, which was drilled to test below the 1991 percussion drill hole B-12 and yielded two significant intervals assaying 0.244 and 0.293 per cent copper with 0.115 and 0.170 gram per tonne gold over 37.65 and 36.75 metres (107.65 to 145.30 and 204.47 to 241.22 metres down hole), respectively (Assessment Report 29453).
In 2011, Moag Copper Gold Resources Inc. completed a program of soil sampling on the area as part of the Ketchan property.
In 2013, West Cirque Resources Ltd. acquired the Aspen Grove property, which consists of 37 mineral claims, totalling 5629 hectares, including the Ketchan Lake North prospect, and proceeded to complete an exploration program of geological mapping and rock sampling throughout the property. Twelve samples were taken from trenches and outcrops at the Ketchan Lake North occurrence and assayed up to 1.07 per cent copper, 0.458 gram per tonne gold and 52.5 grams per tonne silver (Assessment Report 34718; Press Release, West Cirque Resources Ltd., June 11, 2013). Also at this time, a 5.7 line-kilometre ground magnetic survey was completed on the area immediately west of the occurrence as the Ketchan North property.
In 2014 and 2015, KZD Aspen Grove Holding Ltd. and Kaizen Discovery Inc. completed programs of prospecting, geological mapping and 14 diamond drill holes, totalling 3394.0 metres, on the area as part of the Aspen Grove property. Thirteen of these diamond drill holes were completed on the Northwest, Central and Southeast zones of the Ketchan Lake North occurrence area. Potassic and/or calc-potassic alteration with significant intervals of mineralization was encountered in all but one of the holes. Drilling highlights included 1.05 and 0.40 per cent copper with 0.05 and 0.34 gram per tonne gold over 26 and 68 metres (100 to 126 and 70 to 138 metres down hole) in holes K15-10 and K15-11, respectively, on the Northwest zone; 0.27 per cent copper and 0.11 gram per tonne gold over 265.5 metres (4.5 to 270 metres down hole), including 0.50 per cent copper and 0.15 gram per tonne gold over 78 metres (192 to 270 metres down hole), in hole K15-01 on the Central zone; and 0.31 and 0.22 per cent copper with 0.20 and 0.06 gram per tonne gold over 72 and 130 metres (269 to 341 and 189 to 319 metres down hole) in holes K15-03 and K15-05, respectively, on the Southeast zone (Assessment Report 36184). Also at this time, a sample (M457907) of breccia veins with coarse magnetite, actinolite, albite and epidote but no visible sulphides, located approximately 450 metres southeast of the historical hole P-3 (Northwest zone), yielded 0.57 gram per tonne palladium and 0.30 gram per tonne platinum, whereas other surface samples (M457983) from the Central zone yielded up to 2.13 per cent copper, 9.3 grams per tonne silver and 0.204 gram per tonne gold (Assessment Report 36184).
In 2016, KZD Aspen Grove Holding Ltd. and Kaizen Discovery Inc. completed a further eight diamond drillholes, totalling 4009 metres, on the occurrence as part of the Aspen Grove property. Also at this time, a new geological model for the Ketchan Stock was developed and a complete summary can be found in Assessment Report 36432. Drilling highlights included 0.61 and 0.36 per cent copper with 0.39 and 0.15 gram per tonne gold over 20 and 60 metres (111 to 131 and 278 to 338 metres down hole), respectively, in hole K16-07 and 0.46 per cent copper and 0.10 gram per tonne gold over 62 metres (347 to 409 metres down hole) in hole K16-06, both on the Central zone (Assessment Report 36432).
