The Getty North (Krain) deposit is located on the lower eastern slopes of Forge Mountain, approximately 16 kilometres northwest of the community of Logan Lake.
The deposit lies on the southern boundary of an extensive area of post-mineral cover consisting of continental volcanic and interbedded sedimentary rocks of the Eocene Kamloops Group, which overlie plutonic rocks of the Late Triassic-Early Jurassic Guichon Creek batholith. Mineralization occurs within quartz diorites of the Highland Valley phase (Guichon variety) of the Guichon Creek batholith, and within younger anastomosing dikes and small stocks. The dikes and stocks resemble quartz diorites of the Bethlehem phase of the batholith. The Kamloops Group rocks cover the northern half of the mineralized zone, and have protected an older oxidized cap as much as 100 metres thick.
The mineralized porphyry system occurs within a broad northwest- trending zone that also contains the Bethlehem mine (MINFILE 092ISE001), approximately 10 kilometres to the south. This broad zone is characterized by numerous sub-parallel, northwest- trending porphyry dikes, as well as by prominent, fracture-related, but non-pervasive, chlorite-epidote- chalcopyrite ±pyrite ±bornite hydrothermal vein and fracture selvage assemblages. Smaller zones of pervasive chlorite-clay alteration, some containing strong chalcopyrite mineralization, occur frequently at the margins of porphyry dikes.
Mineralization and alteration are closely associated with an elongate, 1000 by 200 metre, dike-like stock, which is unroofed within a small area at the centre of the deposit. The unroofed portion appears to be an abrupt cupola-like projection that developed above the stock. To the northwest and southeast along strike, the apex of the stock plunges gently away from the high point at Krain and the lateral contacts dip approximately 70 degrees to the south west. Fracturing, brecciation, alteration and mineralization are all most strongly developed in and around the central cupola-like core, and along the upper surface of the stock.
Well-defined zonal patterns of primary sulphide mineralization and argillic alteration have been recognized around the core area. Within the core and near the contacts of the stock, chalcopyrite- bornite assemblages are found associated with molybdenite-bearing quartz veinlets. Peripheral to this mineralization, chalcopyrite- pyrite assemblages occur in fracture stockwork fillings in which pyrite becomes more abundant outward, both within the wall rocks and the stock. Maximum total sulphide content is approximately 5 per cent and occurs in a zone approximately coincident with the outer limit of 0.1 per cent copper grades. The deposit measures 400 metres long by 300 metres wide and extends to 450 metres depth. In plan view, the deposit is triangular with the known apex to the southeast. The zone appears to be cut off by a fault to the northwest; the northeast and south boundaries are near vertical.
Fractures and faults are prominent. The areas of highest fracture density, which are adjacent to the stock, are also the zones of best mineralization. Sets of steeply dipping north and northeast- trending faults are dominantly post-mineralization. Kamloops Group rocks are restricted almost entirely to down-faulted blocks, where vertical offsets have been substantiated by drill data.
Associated zoned argillic alteration is pervasive and diminishes outward from sericite-clay-chlorite assemblages in the core, through clay-chlorite and chlorite assemblages in the chalcopyrite zone, to chlorite-epidote assemblages in the pyrite zone. Beyond the approximate outer limit of 0.05 per cent copper grades, argillic alteration is no longer pervasive, although propylitic (chlorite- epidote) alteration forms pronounced fracture selvage halos, which gradually diminish to fracture coatings over transition zones as much as 1000 metres wide. Disseminated calcite forms as much as 5 per cent of the more highly altered and better mineralized rocks and is believed to have greatly influenced the migration of copper at the time of oxidation (Canadian Institute of Mining and Metallurgy Special Volume 15).
The oxidized cap, as much as 100 metres thick, is covered by post-mineralization Kamloops Group rocks. Hypogene sulphides within this cap have been totally destroyed. In contrast, sulphides occur at surface within the southern part of the deposit, where Pleistocene glaciation has removed most of the oxidized zone. The overall average oxide copper grade is approximately 20 per cent higher than the overall average hypogene copper grade, suggesting that copper enrichment has occurred within the cap. Malachite is the most abundant copper mineral, but chrysocolla and a black waxy copper oxide of dendritic habit (neotocite? copper manganese?) are common. These minerals form very prominent fracture coatings, some of which are botryoidal, and also fill cavities previously occupied by sulphides. Minor cuprite and disseminated native copper are found most commonly in the outer parts of the deposit. Chalcocite occurs in minor amounts as thin coatings on corroded grains of sulphide within a narrow zone, extending through the lower metre of oxidized rock to the upper few metres of the primary sulphide zone. Chalcocite is not sufficiently abundant to contribute appreciably to the grade of the deposit, and does not account for the slight enrichment of the oxidized zone over primary grade (Canadian Institute of Mining and Metallurgy Special Volume 15).
Unlike most copper deposits within the Guichon Creek batholith, the Krain deposit displays a strong genetic relationship with a small stock which, in this case, intrudes Guichon quartz diorite. Texturally, the stock resembles the Bethlehem phase of the batholith, and a cupola-like part of it forms a core, about which are developed strong zonal patterns of fracture intensity, sulphide and hydrothermal alteration mineralogy, and copper grade. Mineralized rocks were deeply oxidized prior to burial during the Early Tertiary period. Despite total destruction of sulphides within a thick oxidized cap, very little secondary chalcocite enrichment resulted. Conversely, the oxidized cap itself appears to have become enriched in copper. This enrichment is interpreted to result from the reaction of available hydrothermal calcite to precipitate copper from acid solutions produced during the oxidation process. Downward migration of copper was thereby retarded and, ultimately, with continued weathering and oxidation, the oxidized zone became slightly enriched (Canadian Institute of Mining and Metallurgy Special Volume 15).
The showing was originally staked in approximately 1907 by Messrs. Novak, Johnson, Fraser, and Cowans as the Keystone group of six claims and fractions. Exploration work was done in two adits at the same elevation and approximately 42 metres apart; one was driven 8.5 metres, the other 7.6 metres. In 1955, Farwest Tungsten Copper Mines Limited and Beaver Lodge Uranium Mines Limited jointly staked and optioned 21 claims and fractions in the Krain, D.W. and R.K. groups. Under the terms of the agreement, a new company, Krain Copper Ltd., was incorporated in November 1956. Exploration work was concentrated on the Krain copper claims, which were a relocation of the Keystone group. Exploration work during 1955- to 1956 included trenching, geochemical soil sampling, a magnetometer survey and 2188 metres of diamond drilling. Kennco Explorations (Canada) Limited, through its subsidiary Northwestern Explorations, Limited, optioned the property in 1957. Work, mainly on the R.K. group, included trenching, geochemical and geophysical surveys, and 193 metres of diamond drilling in one hole. The option was dropped late in 1958. In 1960, Rio Tinto Canadian Exploration Limited obtained an option and carried out a geophysical survey and 161 metres of diamond drilling in one hole. North Pacific Mines Ltd. optioned the property from Krain Copper Ltd. in 1965. Work included eight diamond drill holes totalling 2349 metres and 17 percussion holes totalling 806 metres. Canex Aerial Exploration Ltd. held a sub-option until July 1966 and completed 1030 metres of diamond drilling in 16 holes. Krain Copper Ltd. changed its name in 1966 to Krain Copper Resources Ltd. and amalgamated with Comet Mining Corporation Ltd. in May 1966 to form Comet Krain Mining Corp. North Pacific Mines Ltd. purchased an approximate 50 per cent interest in the company in 1967. An option was granted to the "Shulman Syndicate" who carried out 1444 metres of diamond drilling in four holes to test for mineralization under the volcanic cap at the northerly end of the deposit. Work during 1969 was carried out under an agreement with Brameda Resources Limited and Noranda Exploration Company, Limited, and included geochemical and geophysical surveys and 293 metres of percussion drilling in seven holes. Work during 1970 included percussion drilling (1153 metres in 24 holes) in the known oxide zone to obtain samples for leaching tests. A feasibility study was also carried out. The company name, Comet Krain Mining Corp., was changed in 1971 to Comet Industries Ltd. Getty Mining Pacific, Limited, a subsidiary of Getty Oil Company, Los Angeles, optioned the property in 1971. Work by Getty during 1971 and 1972 included induced polarization surveys over 27 line kilometres, resistivity surveys over 9 line kilometres and a geochemical survey (100 samples) over the Krain claims. Diamond drilling totalled 1390 metres in five holes in 1971 and 1972, with a further 821 metres in 1973. Percussion drilling totalled 2143 metres in 23 holes. The Getty option agreement terminated in January 1974.
In 1972, tonnage and grade estimates were made at Krain, including all areas of mineralization that could be recovered from a single 250-metre deep open pit, using a 0.3 per cent copper cut-off grade. The calculations indicated a total reserve of 14 million tonnes grading 0.56 per cent copper and 0.01 per cent molybdenum. Of this total, approximately 9.1 million tonnes, averaging 0.53 per cent copper, contain primary sulphides, and 4.9 million tonnes, grading approximately 0.64 per cent copper, contain secondary copper carbonates and oxidation products (Christie, J.S. (1976), in CIM Special Volume 15).
The ground was apparently restaked in approximately 1974 as the Getty 1- 24 and Getty A Fr., the deposit being on the Getty 1-4 and Getty A Fr. In 1975, the property was reportedly owned by John Lepinski. Percussion drilling in three holes totalling 171 metres was carried out on Getty 17 and 19, approximately 1 kilometre south of the mineralized zone. In 1976, the property was reportedly owned by Robak Industries Ltd. Work carried out by W.R. Financial Consultants Ltd. included 540 metres of percussion drilling in seven holes. TRV Minerals Corporation optioned the property from Robak Industries in May 1980. Work in the period 1978 to 1982 by TRV or its associates, W.R. Financial Consultants and New Minex Resources, included 302 metres of diamond drilling in one hole and a magnetometer survey over 90 kilometres on the Krain and adjacent Trojan properties. In 1984, Robak carried out a geochemical survey comprising 119 soil, six rock and 3three silt samples over the Krain property and the adjacent Transvaal property (MINFILE 092INW040) to the west.
Work by Getty Copper Corp. during the period January 1, 1993 to November 30, 1997 on the Getty North deposit included 35,927 metres of diamond drilling in 142 holes. The deposit has been systematically drilled on northeast-oriented sections established 30 metres apart. The most recent resource calculation (January 1998) yielded an estimate of 72,093,000 drill indicated and inferred tonnes grading 0.31 per cent copper, which includes approximately 13,875,000 tonnes of oxidized material having an average grade of 0.29 per cent copper, and also 44,405,000 tonnes of sulphide-copper –bearing rock having an average grade of 0.37 per cent copper. The oxidized resource includes approximately 10,034,000 tonnes having an average grade of 0.40 per cent copper. A mineable oxide reserve (SX-EW) is 5, 821,000 tonnes of 0.46 per cent copper (http://www.gettycopper.com/projects.html).
In 2004, Getty Copper Inc. drilled several geophysical targets in the vicinity of the Getty North porphyry copper deposit. The following year a program of geological mapping and an induced polarization survey, totalling 193.5 line-kilometres, was completed.
In 2010, Getty Copper released an NI 43-101 compliant update of the probable indicated and inferred resource evaluation of the Getty North and South deposits (Assessment Report 31541):
Deposit Indicated Resources Grade
(millions of tonnes) Copper (%) Molybdenum (%)
North 69.258 0.370 0.005
South 45.148 0.377 No Data
Total 114.406 0.373 -----
Deposit Inferred Resources Grade
(millions of tonnes) Copper (%) Molybdenum (%)
North 18.166 0.271 0.005
South 23.593 0.278 No Data
Total 41.759 0.275 -----
Deposit Probable Reserves Grade
(millions of tonnes) Copper (%) Molybdenum (%)
North 49.691 0.397 0.005
South 36.870 0.405 No Data
Total 86.561 0.400 -----
In 2011, a ground magnetic survey, totalling 19.2 line-kilometres, and an induced polarization survey, totalling 23.2 line-kilometres were completed on the area.