The Thira property is mainly underlain by mafic to intermediate volcanic rocks of the Middle to Lower Jurassic Telkwa Formation (Hazelton Group). Conglomerate and andesitic volcanic strata of the Cretaceous Kasalka Group are exposed to the east, west and north. Undivided volcanic rock of the Lower Cretaceous Mt. Ney Volcanics (Skeena Group) occurs a few kilometres to the south. All these stratigraphic packages are intruded by stocks and dikes of the Late Cretaceous Bulkley or Kasalka Plutonic suites.
Porphyry-style chlorite-biotite-potassium feldspar alteration and associated pyrite plus/minus chalcopyrite mineralization is observed throughout the property and is most intense in proximity to the intrusive bodies. The country rock in the vicinity of the intrusive bodies is strongly fractured. Pyrite/chalcopyrite mineralization occurs as disseminations and fracture fillings in both country rock and intrusions. Pyrite commonly exceeds 3 per cent over broad areas of the property.
Due to the encouragement provided by a mineralized intersection in their 1995 percussion hole PH95-5 (0.18 per cent copper over 67 metres) Cominco Ltd decided to more thoroughly test the 2 by 1.3 kilometre chargeability low associated with that hole (Assessment Report 24109). Later in 1995 three diamond-drill holes were completed. The best mineralization was found to occur in Hole DH95-12.
Hole DH95-12 was collared on the south-eastern edge of the IP low, 330 metres south of hole 10 and 650 metres east of hole 5. It also intersected white feldspar porphyry to a depth of 34.3 metres. Here, however, the white porphyry is mineralized with an average copper grade of 0.054 per cent copper over 22.1 metres, from interval 12.2 to 34.3 metres depth (Assessment Report 24392). The copper mineralization occurs as very fine-grained chalcopyrite and lesser bornite in narrow quartz veinlets. As typical elsewhere this unit is characterized by 5 to 15 per cent fine-grained, disseminated pyrite. At a depth of 34.3 metres the hole passed into a multi-phase granitic intrusion. This intrusion varies from feldspar porphyritic granite, through equigranular granite into weakly feldspar porphyritic granodiorite down the hole.
The granitic intrusion is mineralized throughout with the best mineralized section associated with the equigranular granite between 51.9 and 57.8 metres. This 5.9 metre interval averaged 0.15 per cent copper with weakly elevated gold (to 0.072 gram per tonne over 2 metres) and silver (to 1.2 parts per million over 2 metres) values; molybdenum was weakly elevated throughout the hole ranging from 4 parts per million to 0.011 per cent molybdenum over two metre intervals (Assessment Report 24392).
Alteration in hole twelve is characterized by weak to locally strong fine-grained red-brown biotite, ubiquitous chlorite and locally concentrated strong pink potassic feldspar flooding.
A 2 metre split from hole DH95-10 chalcopyrite (from 78 to 80 metres depth), containing isolated specks of chalcopyrite assayed 0.23 per cent copper, 11.1 gram per tonne silver and 0.094 gram per tonne gold (Assessment Report 24392).
WORK HISTORY
In 1971, Passport Mines performed a geochemistry survey on the Con group of claims to the south of Hill-Tout Lake and Jorax Ltd. performed a geochemistry survey to the northeast of Camp Lake in the Nadi area.
From 1970 to 1973, exploration conducted by Jorex Ltd. and Dome Exploration in the Copper Pond area (093E 071) included soil, silt and lake geochemistry, an aerial mercury survey, ground magnetometer, induced polarization/resistivity, and 2240 metres of diamond drilling. In 1973, they performed additional geophysics as well as soil sampling around the Copper Pond and Camp Lake areas. Dome drilled 14 diamond drill holes over the Copper Pond area and two at Camp Lake. A zone roughly 120 by 275 metres with an average grade of 0.16 per cent copper was outlined at Copper Pond.
The area of the Hill showing (093E 097) saw further work between 1971 and 1974 by Passport Mines Lid. and Quintana Minerals Corporation. They carried out geological, soil and rock geochemistry, an Induced Polarization survey and 36 percussion drill holes totalling 1673 meters.
In 1972, Quintana Minerals Corporation performed mapping, soil and rock sampling over the AFT and HT claims in the Lily area. Jorax performed IP and Resistivity surveys over the Nadi claims as well as an EM and Mag survey in the Copper Pond area.
In 1974, Quintana Minerals Corp. Performed an IP survey over the Lily and Hill Lake areas as well as a percussion drill program in the Hill Lake area.
In 1982, Newmont Exploration of Canada Ltd. performed a Magnetic and IP survey, a soil geochemical survey, and geological mapping over the Nadina property consisting of the CU1 to CU4 claims which were centered on Hill Lake (Assessment Report 11236). A total 51 kilometres of magnetic surveying and 21 kilometres of IP surveying were completed. The CU claims stretched roughly 5 kilometres north from the northeast end of Nadina Lake toward Hill-Tout Lake. The claim block was roughly 2.5 kilometres wide and would have covered the area of the Hill showing (093E 097).
In 1982, Utah Mines established a grid for geological, geochemical and geophysical surveys on their Second claim group (Assessment Report 11034). A total of 53.5-line kilometres were established. The grid area covers the Thira (new) and probably the Dual (093E 053) area. It also covers the area just north of Ida (093E 071). Ida is plotted about 550 metres east of Copper Pond Lake and 800 metres south of Camp Lake. Sixty-eight kilometres of IP were performed and possibly some overburden drilling but no core drilling recorded.
From 1987 to 1992 Placer Dome Inc (inherited property from Dome) completed 12 kilometres of I.P. geophysical surveying at the south-west end of Thera property.
From 1989 to 1990, Swift Minerals Ltd. performed a 6-hole diamond drill totalling 1944 metres program on the Hill property (093E 097) to the southwest of Hill Lake. At least two holes intersected copper mineralization with one 2 metre interval assaying 0.18 per cent copper (Hole 89-1 and 90-4, Sheet 2, Assessment Report 20742). Also, during this year, Placer Dome Inc. and Canadian Jorax Ltd. performed IP and stream sampling over the Thira claims which cover the old Nadi and Ida claims over the Camp Lake area. Results included 1135 parts per billion gold from a moss mat sample.
In 1993 and 1994, Cominco Ltd conducted an airborne geophysical survey over 122 kilometres followed by a 40.3 kilometres of Induced Polarization IP) geophysical survey on the Dual property (Assessment Report 23504). The IP survey area was north, south, east and west of "Gordeau" Lake; the L & H showing (093E 072) is plotted near the southeast corner of the lake. The IP lines extended south close the Ida showing area (093E 071).
From 1994 to 1996, Cominco Ltd held the Thira property. In 1994, Cominco performed one line of IP and Resistivity on the Thira to the southeast of Camp Lake. Soil sampling was also performed to the west of Hill Lake, extending over the Hill showing was south of, or in the vicinity, of the Dual (093E 053) and new Thera showings (Assessment Report 23795). In 1995, Cominco performed soil sampling and 423.7 metres in 8 holes were completed on the Thira Property from Hill Lake to Camp Lake, one hole yielded 0.18 per cent copper over 67 metres (Assessment Report 24109). This was followed by 300.5 metres in 3 diamond-drill holes (Assessment Report 24392). This drilling resulted in a new discovery named after the property, the Thira. Some of the percussion holes were in the vicinity of the Dual showing.
In 2008 and 2009, Lions Gate Metals performed minor prospecting and sampling along this lower road, strong alteration and minor elevated metals were returned.
In 2009, Lions Gate Metals detailed Airborne Electromagnetic and Magnetic survey was flown over their Poplar property which included some claims in this area (Figure 2, Assessment Report 31788). It appears to have covered the areas around Dual (093E 053), Ida, (093E 071) and possibly Hill (093E 097) or just north of it.
In 2011, Lions Gate Metals performed a geochemical soil sampling program with 403 “B” horizon sites over the Copper Pond East target showing three areas of anomalous (greater than 100 parts per million copper).
See Poplar (093L 239) for details of the Lions Gate Metals work completed on their Poplar property.
In 2018 and 2019, Universal Copper Ltd. completed programs of geochemical sampling (rock, silt and soil) and four diamond drill holes, totalling 1648.97 metres, on the area as the Poplar property.
