British Columbia Ministry of Energy, Mines and Natural Gas and Responsible for Housing
News | The Premier Online | Ministries & Organizations | Job Opportunities | Main Index

MINFILE Home page  ARIS Home page  MINFILE Search page  Property File Search
Help Help
File Created: 11-Dec-2013 by Garry J. Payie (GJP)
Last Edit:  31-Jan-2023 by Larry Jones (LDJ)

Summary Help Help

NMI
Name OBAN, THORN Mining Division Atlin
BCGS Map 104K057
Status Developed Prospect NTS Map 104K10W
Latitude 058º 32' 56'' UTM 08 (NAD 83)
Longitude 132º 47' 12'' Northing 6491948
Easting 628803
Commodities Silver, Gold, Lead, Zinc, Copper Deposit Types H04 : Epithermal Au-Ag-Cu: high sulphidation
I05 : Polymetallic veins Ag-Pb-Zn+/-Au
Tectonic Belt Intermontane Terrane Stikine
Capsule Geology

The Oban area is underlain by feldspar-quartz-biotite-phyric diorite of the Late Cretaceous Windy Table Complex (Thorn Stock), which intrudes Upper Triassic Stuhini Group volcanic and sedimentary rocks. A second Late Cretaceous magmatic event deposited subaerial volcanic rocks of the Windy Table Suite non-conformably upon the Thorn Stock, coeval with a second stage of plutonism.

The Oban breccia pipe is hosted within and cuts the Thorn Stock. It contains significant matrix-hosted, silver-rich, pyrite-sphalerite-boulangerite mineralization in several drillholes, with intersections grading up to 38.6 metres at 1.22 grams per tonne gold and 188 grams per tonne silver (Assessment Report 32769). It is considered a high-sulphidation porphyry related breccia zone.

Drilling in 2013 doubled the size of the mineralized footprint at the Oban zone. The zone was expanded to approximately 210 metres in a North-South direction by 150 metres in an East-West direction to nearly 400 metres in depth. As of the 2013 work, the Oban zone remains open at depth and strike in several directions.

The ‘typical’ Oban breccia most closely matches their description of a magmatic-hydrothermal breccia which typically forms pipes or irregular bodies consisting of monomict angular to subrounded clasts within rock-flour matrix, hydrothermal cement, fine-grained igneous material, or some combination of the three. These types of breccia typically transition at depth through increased clast content into unbrecciated intermineral porphyry. The breccia is heterogeneously altered and locally contains fragments that have variable degrees of sericite-clay-ankerite alteration.

Mineralization within the Oban breccia occurs as: semi-massive to massive matrix infill; layers and mixed sulphides and sulfosalts; veinlets and stockwork within crackle breccia and disseminated, veinlet to crackle style breccia. Crackle breccia also form clasts within the diatreme. The dominant minerals are pyrite, sphalerite, silver-sulfosalts tetrahedrite-tennantite-freibergite, lead-sulfosalts (boulangerite), galena, and chalcopyrite. These minerals form layered rims around breccia fragments. The dominant fragments are Thorn Stock (Diorite porphyry). The nature of the mineralization appears to be sub-vertical to sub-horizontal and locally structurally controlled with evidence in core by slickensides and carbonate alteration (ankerite).

Outcrops exposed during trenching in 2003 indicate that the southwestern part of the pipe is weakly sericite-chlorite altered. One small gold-bearing silicified outcrop has been discovered (sample #209603: 25.93 grams per tonne gold, Assessment Report 27379). Trenching proximal to this outcrop failed to expose any similar material and silica-altered zones were not observed in core, suggesting silicification of the breccia is rare.

Three styles of mineralization within the Oban zone occur including: sulphide/sulfosalt replacement and banded millimetre-scale veins rimming fragments, massive sulphides and sulfosalts in float boulders, and silicified breccia with disseminated and fracture-filling tetrahedrite.

The most significant intercept of the 2011 drilling program was in hole THN11-60, was 95.08 metres grading 628 grams per tonne silver, 1.71 grams per tonne gold, 3.31 per cent lead, and 2.39 per cent zinc (Assessment Report 32769).

In 2012, Brixton Metals completed a total of 26 NQ core holes drilled into the Oban breccia zone, for a total of 2,889.67 metres. The best intercept from 2012 drilling was from drill hole THN-12-84, which intersected 310.00 metres of 0.71 gram per tonne gold, 105.82 grams per tonne silver, 0.90 per cent lead, and 1.76 per cent zinc (223.51 grams per tonne silver equivalent) and included 17.00 metres of 1.45 grams per tonne gold, 251 grams per tonne silver, 2.78 per cent lead and 3.99 per cent zinc (526.14 grams per tonne silver equivalent) (Assessment Report 33597).

Brixton Metals Corporation established an inferred resource estimate, compliant with NI-43-101 standards of 21.5 million ounces of silver equivalent (7.4 million tonnes, grading 89.75 grams per tonne silver equivalent) for the Oban, Glenfiddich and Talisker (104K 133) zones combined (Assessment Report 35192). The total in-situ grade for combined zones is 7.4 million tonnes grading 35.54 grams per tonne silver, 0.51 gram per tonne gold, 0.13 per cent copper, 0.32 per cent lead and 0.59 per cent zinc (Assessment Report 35192).

WORK HISTORY

In 2002, prospecting by First Au Strategies Corp within a soil geochemical anomaly resulted in discovery of the Oban breccia pipe. During 2003, Cangold Limited (formerly First Au Strategies) conducted mechanical trenching and drilling of the Oban breccia. In 2004, Drilling by Cangold on the Oban Zone put limits on its extent and significance. During 2011 Brixton Metals carried out an exploration program consisting in 5682.37 metres of drilling.

In 2012, Brixton Metals conducted a two-phase exploration program comprised of 26 diamond drill holes totaling 2,889.67 metres, the collection of 362 soil samples, and one rock sample (Assessment Report 33597). Diamond drilling was focused on delineating mineralization within the Oban breccia zone.

In 2013, Brixton Metals drilled 35 diamond drill holes during a two-phase exploration program for a total of 6.078 metres at the Oban, Talisker and Glenfiddich zones, collected 1,368 soil samples and 13 rock samples, conducted a specific gravity survey on drill core, contracted SRK Consulting Canada Inc. to perform detailed structural analysis of the Thorn Property and carried out reclamation and physical work (Assessment Report 34506). Geochemical analyses resulted in doubling the extent of mineralization in the Oban diatreme breccia.

In 2014, Brixton Metals drilled 8 holes totalling 1,287.46 metres at the Outlaw zone, collected 16 soil samples and completed further reclamation and physical work. Through diamond drilling, mineralization observed at the Glenfiddich Zone was also extended along strike and to a depth of 60 metres. Brixton Metals also established a combined inferred resource estimate for the Oban, Glenfiddich and Talisker zones at 7.4 million tonnes, grading 89.75 grams per tonne silver equivalent (Assessment Report 35192). The open pit portion for the Oban zone was 3.70 million tonnes grading 105.07 grams per tonne silver equivalent (50.82 grams per tonne silver, 0.4 gram per tonne gold, 0.31 per cent lead, and 0.5 per cent zinc). The underground portion of the Oban zone was 0.50 million tonnes grading 113.84 grams per tonne silver equivalent (50.51 grams per tonne silver, 0.46 gram per tonne gold, 0.37 per cent lead, and 0.67 per cent zinc) (Assessment Report 35192). The Talisker inferred open pit resource is 2.10 million tonnes grading 73.77 grams per tonne silver equivalent for 5.00 million ounces of silver equivalent. The Glenfiddich inferred open pit resource is 1.10 million tonnes grading 58.78 grams per tonne silver equivalent for 2.10 million ounces silver equivalent.

In 2016, Brixton Metals carried out a two-phase exploration program at the Thorn Property. During this time, 2303 soil samples and 247 rock samples were collected, a 15.49 line-kilometre Titan-24 DCIP geophysical survey was conducted over the area of the new Chivas Zone, and 9 diamond drill holes were drilled at the Outlaw and Aberlour Zones, totalling 1,644.91 metres (Assessment Report 36638). At the Chivas Zone, a new gold-in-soil anomaly was identified and corresponded with a near surface IP chargeability high, measuring 3.5 kilometres long and 1.9 kilometres wide, and remains open (Assessment Report 36638). Overall, 2016 drilling and sampling efforts extended the Outlaw Gold Zone to 450 metres along strike, which remains open.

In 2017, the Brixton Metals Corporation exploration program on the Thorn property consisted of2455 metres diamond drilling in 10 holes, the collection of 517 soil and 56 rock samples, a 176.60 square-kilometre aerial Lidar geophysical survey and detailed geological and alteration mapping at a 1:2,500 scale. All drill holes targeted the Chivas zone. The majority of rock and soil samples were collected from the Chivas Zone. Some rock and soil samples were also collected at the Cirque Zone, as well as in unexplored areas located north of the Sutlahine River, and northeast and south of the Chivas Zone.

In 2018 Brixton Metal Corporation examined and sampled intrusive and volcanic rocks from drill core and outcrop at the Chivas Zone (THN17-149); as well as drill core from select holes at the Oban (THN11-60 and THN13-119), Talisker (THN11-56) and Outlaw (THN14-128) zones in order to assess district-scale mineralization and metal zoning. The collection of 15 samples for petrographic analysis was carried out in order to document intrusive rock mineralogy and mineralization styles from Chivas, Oban, Talisker and Outlaw (104K 083).

Based on limited core review in 2018, mineralization in the Oban, Talisker, Glenfiddich zones are polymetallic (silver- gold plus/minus lead, zinc, copper) and related to heterolithic breccias (especially at the Oban Zone) and intermediate-to-high-sulphidation veins. Sulphide content commonly exceeds 5 volume per cent primarily as pyrite but with significant galena, sphalerite, tetrahedrite/tennantite, chalcopyrite and boulangerite. For the Oban, Glenfiddich and Talisker area, increasing copper toward the bottom of the deep hole THN13-119 has been noted previously. Selenium and tellurium show a pronounced southward gradient from the Oban holes toward and across Glenfiddich. Glenfiddich holes THN13-121 and 122 contain 2 to greater than 8 parts per million selenium and 3 to 20 parts per million tellurium. Talisker hole THN13-120 is also selenium and tellurium-anomalous but less so than the Glenfiddich holes. Possible interpretations for these findings are a deeper porphyry copper-gold centre possibly resides beneath Oban or a porphyry centre beneath or near the Glenfiddich holes.

In 2019, Brixton conducted geological mapping and soil and rock geochemistry at the Chivas zone expanding the porphyry target to 3 kilometres along strike which remains open. Brixton completed a 9.1 line- kilometre IP-magnetotelluric survey across the Camp Creek copper corridor, which also contains the Oban diatreme breccia pipe and Glenfiddich zone. This survey showed a chargeability high over the Oban zone. Intersections of porphyry-style copper-gold-molybdenum mineralization in multiple 2019 drill holes in the Camp Creek Corridor targets:

THN19-150 (Oban): 554.70 metres at 1.97 grams per tonne gold equivalent (97.00-651.70 metres);

THN19-151 (Oban): 256.87 metres at 2.31 grams per tonne gold equivalent (100.18-357.05 metres);

THN19-162 (Glenfiddich): 230.82 metres at 0.27 per cent copper equivalent (323.00-553.82 metres);

THN19-163 (north of Oban near Camp Creek): 9.03 metres 0.29 gram per tonne gold, 2.87 grams per tonnes silver and 0.2 per cent zinc. (Press Release, Brixton Metals Corp., Dec.19, 2019). Drill hole THN19-163 was designed to test the high chargeability anomaly delineated by the fall 2019 TITAN 24 DCIP Survey conducted in the Camp Creek area. The hole intersected gold-silver-zinc mineralization, which is hosted mainly in a matrix rich diatreme breccia unit and consists of sulphides as disseminated or veins.

Drilling extended the Oban Zone polymetallic mineralization to a depth of 651 metres from the previously drilled vertical depth of 370 metres for an increase of 281 metres of new mineralization THN19-150 returned 554.70 metres of 0.57 gram per tonne gold, 0.24 per cent copper, 43.18 grams per tonne silver, 0.55 per cent zinc and 0.28 per cent lead, for a 1.97 grams per tonne gold equivalent (AuEq) over 554.70 metres (Press Release, Brixton Metals Corp., July 15, 2019).

In 2020, Brixton Metal Corporation completed 3,025 metres of drilling within 16 core holes on the Central Outlaw zone and on the new West Outlaw zone. A total of 1473 rock samples and 5588 soil samples were collected throughout the Thorn property (Press Release, Brixton Metals Corp., Dec.15, 2020).

In June 2021, an updated mineral resource for the Oban openpit deposit was reported at 3 961 000 tonnes inferred grading 48.20 grams per tonne silver, 0.38 gram per tonne gold, 0.29 per cent lead and 0.56 per cent zinc, plus and additional underground inferred resource of 605 000 tonnes inferred grading 48.15 grams per tonne silver, 0.43 gram per tonne gold, 0.35 per cent lead and 0.66 per cent zinc (Burrell, H., Deiss, A.M. [2021-06-23]: Thorn Property NI 43-101 Technical Report Sutlahine River Area, British Columbia, Atlin Mining Division).

Refer to Thorn (104K 031), Chivas (104K 180) and East Outlaw (104K 083) for further details of the work history of the Thorn property, of which the Oban zone is part of. Also refer to Talisker (104K 133) and Glenfiddich (104K 186) for related information.

Bibliography
EMPR AR 1963-6; 1964-11; 1965-17
EMPR EXPL 1981-242; 1983-546; 1999-19-31; 2000-1-8; 2003-6; 2004-26; 2005-28
MER 2003-16; 2004-13; 2005-7
EMPR OF 1998-8-E, pp. 1-25
EMPR PF (Offering of Rights. Consolidated Inland Recovery Group Ltd.; Rimfire Minerals Corporation Website (Feb.2000))
GSC MAP 6-1960; 1262A
GSC MEM 362, p. 56
GCNL #183, 1968; #57,#139, 1986; #128(Jul.5), #196(Oct.13), 2000
N MINER Aug.12, Dec.2, 2002; Oct.28, Sept.8,25, 2003
N MINER Aug.12, Dec.2, 2002; Oct.28, Sept.8,25, 2003
PR REL Cangold Limited (First Strategies Au Corp.), Jan.17 2002; Oct.10, 2002; Apr.3, May15, Jun.5; Jun.29, Sept.24, 2003; Rimfire Minerals Corp., Mar.26, Jul.15, Dec.5, 2002; Jun.9, Nov.12,24, Dec.18, 2003; Jun.29, 2005; Rimfire Minerals Corp. and Cangold Limited Oct.10, 2002; Jun.24, Aug.27, Sept.25, Oct.27; Jun.4, Aug.4, Sept.27, Nov.18, 2004; Jan.7, Jun.6, Jul.26, Aug.8, 2005; Kiska Metals Corp. Sept.4, 2012; Brixton Metals Corporation; Aug.*17, Sep.6, Oct.*25, Nov.*28, 2011; Jan.5, Feb.*22, Jul.*18, Sep.*4, Nov.*5,*26, 2012; Aug.*8,*28, Jan.*5, 2013; Jan.9, Jul.*29, Oct.*29, 2014; Aug.5, Oct.31, Nov.9,24, 2016; *Aug.17, Sep.*7,*13, 2018; May 14, Jul.*15, Aug.27, Oct.*30, Nov.14, Dec.*19, 2019; Sep.10, Nov.16, Dec.1,15, 2020
Baker, D. (2010-10-28): 2010 Technical Report on the Thorn Property
*Burrell, H., Deiss, A.M. (2021-06-23): Thorn Property NI 43-101 Technical Report Sutlahine River Area, British Columbia, Atlin Mining Division

COPYRIGHT | DISCLAIMER | PRIVACY | ACCESSIBILITY