The Copper Canyon occurrence area is located along the south flank of the Stikine Arch and is dominated by deformed Mississippian to Middle(?) Jurassic island arc volcanics and sedimentary strata intruded by coeval subvolcanic plutons, Jurassic to Tertiary satellitic Coast Plutonic Complex batholithic plugs and Tertiary felsic to intermediate stocks and dikes.
The Copper Canyon property largely covers a gossanous Upper Triassic to Middle Jurassic alkalic porphyry copper-gold-silver system north of the Copper Canyon Glacier. The system is associated with an irregular northeast elongate and southwesterly splayed, intensely fractured stock-like composite body of pre and intra- mineral alkalic intrusions (the Copper Canyon Intrusions which are correlated with the Early-Middle Jurassic Galore Creek Intrusions). The intrusions either dip or are indicated to plunge moderately to steeply to the northeast and have the general surface form of an inverted irregular U-shaped mass. These intrusions are emplaced into a gently to moderately northwesterly dipping comagmatic alkalic volcanic sequence (Upper Triassic Stuhini Group) along the footwall side of a moderately east dipping pre-alkaline intrusive thrust fault.
These rocks are complexly faulted by a system of northeast and north-northwest faults associated with the arms of the U-shaped intrusive mass. Thrust plate rocks comprise an overturned, moderately easterly dipping sequence of probable Stuhini Group volcanics adjacent the thrust, which are progressively overlain or fault juxtaposed to the east by a Middle Triassic assemblage of black shale, cherty mudstone and chert and Permian limestone. Most of the movement on the thrust fault is indicated to be pre-alkalic complex. Narrow felsic to intermediate and locally lamprophyre post-mineral Tertiary dikes trending northeast to north and west-northwest and steeply dipping, occur locally within and outside to the northeast and west of the property. They particularly occur within or near the Western and North Copper zones, and include a few curvilinear dikes extending fully across the mineralized alkalic complex and into thrust plate rocks with limited offsets due to post-emplacement movement on the thrust.
The Stuhini Group, west of the thrust fault, consists of a gently to moderately northwesterly dipping (average 30 degrees) sequence of grey, maroon, brown and rusty brown weathering alkalic volcanic flows and fragmentals. The sequence is subdivided into four main units, from bottom to top, comprising a trachyte tuff breccia unit, a trachyandesite unit, a trachyte flow unit and a thick trachyte fragmental flow unit.
The irregularly U-shaped body of Copper Canyon Intrusions are a stock-like composite mass of stocks and dikes, generally subdivided into several phases. A splayed extension to the north along the footwall of the thrust fault from the top of the north half of the U-shaped feature, define the North stock-Main body; a smaller lower arm with two associated separate, small outlying bodies to the south along the thrust fault define the North stock-Southeast apophyses. Other phases include a number of separate small dikes and stock-like bodies that occur to the southwest along the north arm of the intrusive complex and which define the Southwest intrusions. A series of generally north-northwest trending intra-mineral dikes are focused along the southwestern end of the north arm of the intrusive complex. Major northeast trending moderately to steeply outward dipping probable normal fault structures (West and East faults) both follow and controlled emplacement along the inner side of the U-shaped composite body.
The North stock-Main body is comprised predominantly of highly fractured, fine-grained, equigranular biotite monzonite. Two associated phases include a limited border phase of medium-grained hornblende syenomonzonite and a separate dike-like body of intrusive breccia.
The North stock-Southeast apophyses includes a main body of fine to medium-grained biotite monzonite. Other associated bodies include a dike-like mass consisting of monzonite intrusive breccia, a small local phase of pink syenite and two separate bodies of medium-grained hornblende monzonite and syenodiorite.
The Southwest intrusions include 3 separate intrusions consisting of medium-grained biotite monzonite, medium-grained monzonite and medium-grained syenite.
Intra-mineral dikes are comprised of potassium feldspar syenite megaporphyry, intrusive breccia, glomeroporphyrytic syenite-monzonite porphyry and medium-grained monzonite.
Post-mineral dikes are felsic to intermediate in composition and locally lamprophyric.
The porphyry mineralized system centred within the property consists of three large, interconnected tabular, arcuate or ring-shaped copper-gold-silver mineralized zones (Western, Eastern and North zones), each measuring up to 610 metres long and 274 metres wide, that are distributed in the general forms of a northeast oriented, inverted, irregular U-shaped mineralized area associated with the similarly distributed alkalic intrusive complex. Irregularities in the U-shaped form of both mineralized zones and the alkalic complex include an extension to the north along the footwall of the thrust fault from the upper portion of the U-shaped feature and a smaller lower arm. Major northeast trending, moderately to steeply outward dipping, normal fault structures (West and East faults), follow the inner side of the U-shaped mineralized area and commonly define the footwall of concordantly dipping mineralized zones. Other similarly trending normal faults tend to occur in the vicinity of the hanging wall side of the Western and Copper zones. Also, a system of apparent strike-limited north-northwest trending and steeply easterly dipping faults occur within the northern arm of the U-shaped intrusive complex and are spatially associated with the Western zone and southeastern portion of the North zone which occurs along strike to the northeast from the Western zone.
Both the North and Eastern zones are hosted in the alkaline intrusive complex (North stock); whereas, the Western zone is dominantly hosted in alkaline volcanic rocks, although it is spatially related with a number of intrusive phases including a pre-mineral small central plug of altered syenite and intrusive breccia and a strike-limited north-northwest trending intra-mineral syenite megaporphyry dike swarm. All mineralized zones are open along strike to the southwest and at depth to the northeast.
Hydrothermal alteration of all pre-Tertiary rocks is widespread, weakly to intensely developed, and is typically pervasive although fracture, shear and, to a certain extent, lithologically controlled. It occurs throughout and centred about the Copper Canyon Intrusions and proximal surrounding country rocks. Alteration products recognized in the system, exclusive of intra-mineral dikes, include potassium feldspar, biotite, garnet, white argillic clay minerals, chlorite, carbonate and local calc-silicate minerals with associated silicification, and sporadic epidote. Associated gangue minerals include specular hematite and earthy hematite, magnetite, anhydrite, fluorite and local zeolites (probably chabazite and natrolite), gypsum and calcite.
The Western, Eastern and North Copper mineralized zones are characterized by fracture-controlled and disseminated chalcopyrite (generally 1-3 per cent and locally up to 10 per cent) and pyrite (1-3 per cent) with related gold and silver values in association with pink, orange and brick-red potassium feldspar flooding and biotitization with common fine specular hematite and minor fluorite. Widespread malachite occurs in all zones on surface and local pads of malachite-azurite-chrysocolla with black copper oxides occur locally in the Western zone.
Drilling in 1990 in the Western zone has also identified i) an extensive, pervasive and fracture-controlled garnetized zone, with associated potassium feldspar and biotite and locally associated light-coloured calc-silicate altered and/or silicified zones, at depth adjacent or near to the footwall of the mineralized zone and ii) widespread and abundant late anhydrite-filled fractures, particularly at depth within the garnetized zone and within intra-mineral syenite dikes, that locally contain chalcopyrite and less frequently galena and sphalerite with associated fluorite, calcite and zeolites.
Best copper mineralization and most intense potassium feldspar flooding and biotitization encountered to date occur on surface and at depth in the Western zone, and to a lesser extent in the southwestern portion of the Eastern zone and in the southeastern portion of the North zone along strike the Western zone.
Mineralized zones i) are centred within a larger outer peripheral zone of pyritization (1-3 per cent pyrite; up to 5 to 10 per cent pyrite occurs in zones overlapping the outer margins of the copper zones) with associated weaker potassium feldspar flooding and biotitization that essentially encompasses the U-shaped intrusive complex and extends to the southwest beneath the Copper Canyon Glacier and ii) surround an inner pyritized region (5 to 15 per cent pyrite that also occurs overlapping the inner margins of the copper zones) with associated potassium feldspar flooding, biotitization and argillic alteration. The latter principally occurs along the footwall sides of the East and West faults adjoining the copper zones. Outwards, the pyritized zone is followed by widespread earthy hematite and propylitic altered (chlorite, carbonate and minor epidote) rocks to the northwest, north, northeast and southeast.
The original claims were staked in August 1956 by the American Metal Co. Ltd., a predecessor company of Canamax Resources Inc., to cover prominent malachite-stained limonitic outcrops. Limited small diameter diamond drilling (7 holes, 1009 metres) was conducted in 1957. Based on this drilling, 24.5 million tonnes at 0.72 per cent copper, 0.41 gram per tonne gold and 10.3 grams per tonne silver was inferred (27 million tons grading 0.72 per cent copper, 0.012 ounce per ton gold and 0.30 ounce per ton silver).
Apart from limited geophysical surveys in the period 1962 to 1966, the property remained dormant until 1988, when it was re-examined by Canamax for its gold potential, and mapped by the British Columbia Geological Survey as part of regional mapping of the Galore Creek area (Fieldwork 1998). This coincided with a period of greatly increased exploration activity in northern British Columbia following the discovery of the Snip gold deposit (104B 250) in the Iskut River area 30 kilometres to the south-southeast.
In 1990, the Copper Canyon property was optioned to Consolidated Rhodes Resources Ltd., who carried out a diamond drilling program in the fall of that year totalling 3805 metres in 13 NQ diamond core holes. The property is held by Canada Tungsten Inc. as the C.C. claims.
Drill indicated resources (1990) of the Copper Canyon are 32.4 million tonnes grading 0.75 per cent copper, 17.1 grams per tonne silver, and 1.17 grams per tonne gold (CIM Special Volume 46, pages 645-649).
The claims remained in good standing until they lapsed in August, 2001. The property was immediately staked by Bernie Kreft, of Whitehorse. Eagle Plains Resources subsequently optioned the property from Kreft, acquiring a 100 per cent interest. NovaGold Resources Inc. took over as operator of the property and may acquire and 80 per cent interest under an option agreement with Eagle Plains Resources.
The geological work in 2004 by NovaGold which includes mapping and drilling, has confirmed previous results and extended the known area of mineralization to the northeast, while the zone remains open to the north, northwest, south, southeast, east and down dip. Eight holes were completed in 2004 (3017 metres) to augment data from 21 prior holes.
NovaGold began exploration of the property in 2004 by completing an eight hole, 3,024 metre diamond drill program. As part of a larger program within the Galore property. NovaGold also drilled several other exploration targets on nearby properties that year. The purpose of the Copper Canyon drill holes was to confirm the historic resource and expand the known limits. An airborne magnetic and radiometric geophysical survey of 1,072 line kilometres was flown by Fugro Airborne Surveys as part of a larger program to delineate anomalies as potential drill targets. The results of the 2004 drilling program provided the basis for geological modelling, and a 43-101 compliant resource estimation and economic evaluation at a pre-feasibility level was also completed.
The mineral resource estimate for the Copper Canyon property incorporates the 1990 and 2004 drill results which total 6,834 metres in 21 holes. There is an estimated NI 43-101 compliant inferred mineral resource of 164.8 million tonnes grading 0.351 per cent copper, 0.539 gram per tonne gold and 7,154 grams per tonne silver per tonne at a 0.35 per cent copper equivalent cutoff (Geology and Resource Potential of the Copper Canyon Property, February 2005, http://www.eagleplains.ca/bc/copper.html).
Between 2005 and 2006, NovaGold completed four drill holes, totalling 1,413 metres at Copper Canyon to test for extensions of known mineralization zones and to explore geophysical targets. The results of the 2005 drill program confirmed results of past campaigns. In July of 2005, contracted geophysicists completed a 2.5-kilometre, 100-metre pole-dipole IP line (GPL-18) along the East Fork of Galore Creek; 734 metres of this line fell within the boundaries of the Copper Canyon claims. Geologists spent several days in 2005 on the Copper Canyon property prospecting the area of the IP line. The 2006 drill hole, designed specifically to test the northwest dipping extension of the ore body encountered three 7 to 10 metre thick gold intercepts of greater than 0.9 gram per tonne gold at 90.00 to 110.65 metres, 186.50 to 194.00 metres and 467.00 to 474.50 metres.
In 2007, NovaGold completed a twelve hole, 4,940.28 metre diamond drill program at Copper Canyon. This program tested upslope historic soil anomalies, as well as the depth and lateral extensions of the current deposit. The results of four holes only, totalling 1,659 metres are found in Assessment Report 30184.
Drilling by NovaGold in 2007 focused on testing up-slope historic soil anomalies as well as testing the depth and lateral extensions of the current deposit. Drill hole CC07-0033, the deepest hole on the property, intersected a lower zone of mineralization that had not been observed previously below CC90-02 mineralization. Holes CC07-0035 and CC07-0036 further restricted the exploration potential to the east of the known deposit area. CC07-0036 did, however, yield two intervals of 2.5 metres of high gold values (31.9 and 26.8 grams per tonne gold) about 25 metres apart (Assessment Report 30184).
In 2011, NovaGold Resources Inc announced its intent to sell part or all of its 50 per cent ownership in the Galore Creek (MINFILE 104G 090) copper-gold project which may include the Copper Canyon property.
