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Occurrence Details


Occurrence Number
115J 015
Occurrence Name
Treble A
Occurrence Type
Hard-rock
Status
Showing


General Information

Secondary Commodities: copper, gold, arsenic, antimony, molybdenum, lead
Aliases: Elw, Crock, Lll, Selwyn
Deposit Type(s): Vein Au-Quartz
Location(s): 62.568950 N, -138.130640 W
NTS Mapsheet(s): 115J09
Location Comments: Location marks highest gold assay from a rock sample found to date.
Hand Samples Available at YGS: No
Last Reviewed: Feb 1, 2018

Capsule

Last Updated: Feb 1, 2018

WORK HISTORY

             *In Jan/2018 the occurrence was moved approximately 5.75 km to northeast to mark highest gold assay from a rock sample found to date.

Staked as Crock cl 1-24 (Y36198) in Aug/69 by Dawson Range Joint Venture (Straus Exploration Inc, Molybdenum Corporation of America, Trojan Consolidated Mines and Great Plains Development Company of Canada Ltd), following a regional reconnaissance silt sampling survey conducted earlier in the year. The joint venture carried out prospecting, grid soil sampling and reconnaissance geological mapping later in the year.
 
In Dec/69 Montana Mines Ltd fringe staked Jackie cl 1-24 (Y47646), cl 57-72 (Y47670), cl 85-100 (Y47686), cl 113-128 (Y47702) and cl 141-152 (Y47718) on the west, north and east sides of the Crock claims. The claims were one of four claim groups the company held in the area. The company carried out prospecting and reconnaissance soil sampling in 1970.
 
In 1974 Klotassin Joint Venture (Newconex Canadian Exploration Ltd, Marietta Resources International Ltd and Molybdenum Corporation of America) conducted a regional exploration in the area. The joint venture collected soil and silt samples within the occurrence area.
 
In 1980 the Nat Joint Venture (Chevron Canada Limited and Armco Mineral Exploration Ltd) prospected and collected a series of reconnaissance-scale soil samples from the occurrence area.
 
Restaked in Jun/85 as ELW cl 1-68 (YA91922) and cl 73-94 (YA91990) by Chevron Canada Resources Ltd which operated as the Freegold Venture. The claims formed the Selwyn property and were explored with prospecting, geological mapping and wide spaced grid soil sampling later in the year.

In Apr/2010 Strategic Metals Ltd staked LLL cl 1-220 (YD56521) south of the occurrence. The claims were one of four claim groups comprising the Selwyn Project. On June 9, 2010 the company optioned the Selwyn Project (LLL, NNN and OOO claims) and three other claim groups to Central Resources Corp in return for staged payments of cash, and shares. Strategic Metals retained a 3 % net smelter return (NSR) on the properties. During the summer Central Resources prospected, rock sampled and carried out widely spaced reconnaissance soil and stream sediment sampling and localized grid soil sampling.
 
Central Resources added LLL cl 221-229 (YD07275) in Aug/2010, cl 229-446 (YD90609) in Sep/2010 and cl 447-685 (YD121007 in Dec/2010. The newly staked area included this occurrence.
 
In 2011 Central Resources prospected, and carried out follow-up rock sampling and soil sampling on anomalous areas identified in 2010. The company also carried out reconnaissance and grid soil sampling on newly staked areas of the property. 
 
On March 12, 2013 Central Resources fulfilled its financial obligations to Strategic Metals and obtained 100 % interest in the Selwyn Project (LLL, NNN and OOO claims). Strategic Metals retained its net smelter return.
 
On October 2, 2014 Central Resources reorganized and changed its name to Uranium Standard Resources. On March 16, 2015 Uranium Standard sold its interest in the Selwyn Project (including the LLL claims) back to Strategic Metals in return for Uranium Standard shares held by Strategic Metal. On September 15, 2016 Uranium Standard changed its name to Palisades Venture Inc. On July 6, 2017 Palisades Venture changed its name to Fremont Gold Ltd. All documents and press releases relating to Central Resources and Uranium Standard can be found under Fremont Gold’s SEDAR listing.
 
At the end of Mar/2015, Strategic Metals flew a helicopter-borne magnetic and radiometric survey over the LL claims. In Apr/2015 Strategic Metals allowed many of the outlying LLL claims to lapse including the claims covering this occurrence. The company retained 116 LLL claims which covered the core of the claim block. 

In Jun/2015 Strategic Metals restaked the occurrence within LLL cl 387-398 (YC98464) and cl 399-410 (YE66381). The company carried out follow-up rock and grid soil sampling later in the month.
 
On December 19, 2016 Strategic Metals Ltd announced a spin-out transaction to segregate some of its assets (including the LLL claims) into a separate company to be called Trifecta Gold Ltd, a wholly owned subsidiary. Strategic proposed to provide the company sufficient funds to qualify for a listing on the TSX Venture Exchange in return for shares in Trifecta Gold, the majority of which were distributed to Strategic shareholders. The plan was approved by Strategic shareholders on April 21, 2017. The Plan of Arrangement was approved by security officials and Trifecta’s shares were listed on the TSX Venture Exchange on June 15, 2017.  As part of the deal the LLL claim block was renamed the Treble property.
 
In 2017 Strategic Metals carried out closely spaced grid soil sampling within and northwest of anomaly A, hand trenching within the anomaly and minor prospecting in and around anomaly C.

GEOLOGY
 
The Treble property lies approximately 18 km southeast of Mount Cockfield in west-central Yukon. There is no road access to the property, however the proposed Freegold road extension to the Casino mine (Minfile Occurrence #115J 028), if built would run approximately 12 km to the northeast. Access to and from the property is currently obtained by helicopter from Carmacks or other local seasonal bases.
 
The Treble property lies in the centre of the Dawson Range Gold Belt, about 55 km southeast of the Coffee deposit (Minfile Occurrences #115J 110, 111). The northeast portion of the property is underlain by Late Devonian and older Snowcap Assemblage siliciclastic rocks composed mainly of quartzite, micaceous quartzite, and psammitic quartz-muscovite-biotite schist. The Snowcap Assemblage is intruded by Middle to Late Permian Sulphur Creek Suite potassic feldspar and quartz porphyritic to equigranular syenogranite to granite rocks.
 
These units form the basal package which is intruded by the Dawson Range batholith which is assigned to the Mid-Cretaceous Whitehorse Suite. The batholith is composed of granodiorite, lesser granite, tonalite, quartz diorite and diorite rocks which covers the majority of the property. Late Cretaceous to Tertiary quartz monzonite to dacite porphyritic rocks assigned to the Casino Suite intrude all of the units. Paleocene to Lower Eocene rhyolite and dacite dykes assigned to the Rhyolite Creek complex intrude the batholith. 

An approximately three by four kilometre zone of argillic alteration hosting disseminated tourmaline is centred over the original occurrence site, where feldspar porphyry intrudes the batholith. In the northwest corner of the property, there is evidence for a tightly folded, northwest plunging anticline. The axis of this anticline has been intruded by an elongated body of intermediate granitic rocks and its limbs are truncated on both sides by the batholith. The dominant structural feature in the vicinity of the property is the northwest-striking Big Creek Fault which lies approximately 7 km to the northeast. This steeply dipping feature is poorly understood but appears to have played an important role in localizing mineralization in the district.
 
Although unstated, it appears the Crock claims were staked while exploring for porphyry style mineralization similar to that discovered in 1968-69 at the Casino deposit  (Minfile Occurrence #115J 028) located approximately 36 km to the northwest. Soil sampling outlined several weak spot anomalies. Prospecting led to the discovery of the original Crock occurrence (641832 E, 6939785 N). The occurrence is reported to consist of a body of quartz-feldspar porphyry intruding granodiorite of the Dawson Range batholith. A chilled margin was observed at the contact near which disseminated chalcopyrite was found but copper, molybdenum and lead assays were reported to be quite low.
 
Succeeding soil and silt sampling programs tested for porphyry and/or bulk tonnage gold deposits. Although some weak copper and gold spot anomalies were identified no significant in situ mineralization was found. Geological mapping carried out in 1985 for the Freegold Venture identified several highly siliceous breccia zones associated with altered porphyry dykes but sampling of these zones returned only slightly elevated values for gold.
 
Strategic Metals staked the property for its gold potential. The company used historical geochemical results collected by Archer, Cathro & Associates (1981) Ltd during previous exploration programs to narrow their focus. Soil sampling carried out by Central Resources in 2010 and 2011 outlined 3 multi-element soil anomalies labeled A, B and C. 

Anomaly A lies near the contact between Snowcap Assemblage siliciclastic and Sulphur Creek plutonic rocks which has been intruded by a large Casino Suite quartz-feldspar porphyry. It measures approximately 1 000 m by 1 200 m and is characterized by moderately to strongly anomalous values for gold (20 to 502 ppb), arsenic (100 to 810 ppm), antimony (5 to 23 ppm), copper (50 to 346 ppm) and molybdenum (2 to 12 ppm). Lead values are generally background to moderately anomalous with the exception of a single-point value of 128 ppm. The anomaly lies within a larger 2 000 by 3 000 m northwesterly elongated zone of scattered weakly to strongly anomalous gold values and pathfinder elements.
 
Prospecting in 2011 identified a 100 by 120 m zone of breccia float within anomaly A. A rock sample of hydrothermal quartz breccia containing vugs filled with limonite and minor stibnite returned an assay of 14.15 g/t gold, 140 ppm arsenic, 10 ppm antimony and 130 ppm barium (occurrence location). A second rock sample measuring approximately 60 by 40 by 30 cm, consisting of scorodite-stained epithermal quartz containing abundant cross-cutting black sulphides, quartz bands and limonite –filled quartz cavities returned an assay of 1.125 g/t gold, greater than 1 % arsenic, 81 ppm antimony and 3 060 ppm barium.
 
Anomaly B measures approximately 600 by 1 000 m and lies approximately 8.5 km to the southwest (~ 639545 E, 6937785 N). It is underlain by massive granitic rocks assigned to the Dawson Range batholith which has been intruded by Casino Suite quartz-feldspar porphyry. The anomaly straddles the Selwyn River and two of its tributaries. It returned moderately to strongly anomalous values for gold (up to 391 ppb), copper (up to 219 ppm) and lead (up to 401 ppm) and background to moderately anomalous values for arsenic (up to 158 ppm), antimony (up to 13 ppm) and molybdenum (up to 19 ppm). 

Anomaly C discovered in 2011 lies approximately 5.75 km to the southwest (~ 642635 E, 6938755 N) and is centred over the argillic alteration zone discovered during a previous exploration program. The anomaly is underlain by granitic rocks assigned to the Dawson Range batholith and measures approximately 700 by 900 m. It returned a cluster of strongly anomalous gold values (up to 191 ppb) and weakly to moderately anomalous values for arsenic (up to 301 ppm), antimony (11 ppm), copper (up to 95 ppm), lead (up to 152 ppm) and molybdenum (up to 11 ppm). A single spot gold anomaly (123 ppb) lies 500 m to the north, adjacent to a creek.
 
The 2015 airborne geophysical survey helped Strategic Metals refine its understanding of the geology underlying the property. Follow-up soil and rock sampling did not return any significant results. Soil sampling carried out in 2017 expanded soil anomaly A to the southwest. Hand trenching carried out on anomaly A did not reach bedrock; however a composite sample of float specimens collected from within the trench returned 0.90 g/t gold, 387 ppm arsenic and 14 ppm antimony across 3 m. Prospecting carried out over anomaly A returned a specimen of limonitic hydrothermal breccia which assayed 0.885 g/t gold, 1 170 ppm arsenic and 41 ppm antimony. 



 

Location Map

Last Updated: Feb 2, 2018

Work History

Year Work Type Comment
2017 Geochemistry: Soil Closely spaced grid soil sampling around and northwest of Anomaly A.
2017 Other: Prospecting Minor prospecting in and around anomaly C.
2017 Trenching: Hand Attempted to trench on anomaly A, didn't reach bedrock.
2015 Airborne Geophysics: Magnetic Also radiometric survey.
2015 Geochemistry: Soil Follow-up rock and grid soil sampling.
2011 Geochemistry: Soil Follow-up soil and rock sampling of anomalous areas. Grid soil sampling over newly staked areas.
2010 Other Widely spaced reconnaissance soil and silt sampling, minor rock sampling, localized grid soil sampling.
2010 Other: Prospecting
1985 Other: Prospecting
1985 Geochemistry: Soil Wide spaced grid sampling.
1985 Geology: Regional Bedrock Mapping
1980 Geochemistry: Soil Reconnaissance scale sampling.
1974 Geochemistry: Soil Also silt samples, collected as part of regional reconnaissance program.
1969 Geochemistry: Soil Grid based.
1969 Geology: Regional Bedrock Mapping
1969 Geochemistry: Silt Company carried out reconnaissance silt sampling program before staking claims.

Regional Geology - Terrane

Group: Intermontane
Affinity: W Laurentia
Name: Yukon-Tanana
Realm: peri-Laurentian


Regional Geology - Bedrock

Supergroup:
Group/Suite: Snowcap
Formation:
Member:
Terrane: Yukon-Tanana
Period Max: Ediacaran
Age Max: 635 MA
Period Min: Devonian
Age Min: 375 MA
Rock Major: quartzite, psammite, schist
Rock Minor:
Reference: Ryan et al. (2013) - GSC CGM 116
Geological Unit (1M): PDS
Geological Unit (250K): PDS1

Assessment Reports that overlap occurrence

Report Number Year Title Worktypes Holes Drilled Meters Drilled
097093 2017 Assessment Report describing Geochemical Sampling and Hand Trenching at the Treble Property Rock - Geochemistry, Soil - Geochemistry, Hand - Trenching
096744 2015 Helicopter-Borne Magnetic and Radiometric Surveys at the LLL Property Gamma-Ray Spectrometry - Airborne Geophysics, Gamma-Ray Spectrometry - Airborne Geophysics, Magnetic - Airborne Geophysics, Magnetic - Airborne Geophysics
095810 2011 Geochemical Sampling and Prospecting at the LLL Property Rock - Geochemistry, Rock - Geochemistry, Soil - Geochemistry, Soil - Geochemistry, Prospecting - Other, Prospecting - Other
095500 2010 Assessment Report Describing Geochemical Sampling and Prospecting at the LLL Property Rock - Geochemistry, Rock - Geochemistry, Rock - Geochemistry, Soil - Geochemistry, Soil - Geochemistry, Soil - Geochemistry, Prospecting - Other, Prospecting - Other, Prospecting - Other

Related References

Number Title Page(s) Document Type
ARMC016555 Photo interpretation map of geology with coloured sections - 115J/9 - Selwyn River Geoscience Map (Geological - Bedrock)
ARMC016554 Photo interpretation map showing claims - 115J/9 - Selwyn River Geoscience Map (General)
ARMC016556 Geology map - 115J/9 - Selwyn River Geoscience Map (Geological - Bedrock)
ARMC012447 Location sketch - Crock 1-24 - Claim sheet 115J/09 Geoscience Map (General)
MIR1969_70 Mineral Industry Report 1969 - 70 p. 68. Annual Report
Citations
CANADIAN AND AMERICAN MINES HANDBOOK 2014-2015, p. 102.
CENTRAL RESOURCES CORP AND STRATEGIC METALS LTD, Apr/2012. Assessment Report #095810 by H. Smith.
CENTRAL RESOURCES CORP AND STRATEGIC METALS LTD, Oct/2011. Assessment Report #095500 by H. Smith.
CENTRAL RESOURCES CORP, News Release. 9 Jun/2010, 2 Oct/2014.
FREEGOLD VENTURE, Dec/1985. Final Report Freegold Venture December 1985 by .D. Eaton and W.H. Halleran. (Available in the EMR Library).
MINES HANDBOOK 2017-2018, p. 178, 434.
NAT JOINT VENTURE, Dec/80. Final Report Nat Joint Venture, 19 Dec/80 by A.R. Archer and E.P. Onasick. ((Available in the EMR Library).
RYAN, J.J. ET AL., 2013. Geology, Stevenson Ridge (northeast part), Yukon; Geological Survey of Canada, Canadian Geoscience Map 116 (preliminary), scale 1:100 000.
RYAN, J.J. ET AL., 2014. Paleozoic tectonostratigraphy of the northern Stevenson Ridge area, Yukon. Geological Survey of Canada, Current Research 2014-4, 13 p.
SEDAR, Jan/2018. Issuer Profiles – Freemont Gold Ltd. Contains historic press releases for Central Resources, Uranium Standard Resources and Palisades Venture Inc.
STRATEGIC METALS LTD, Apr/2015. Assessment Report #096744 by H. Burrell.
STRATEGIC METALS LTD, Mar/2014. Notes to Consolidated Interim Financial Statements, for the three months ended March 31, 2015 and 2014, p. 21. Outlines transfer of Selwyn Project (i.e. LLL claims and others) back to Strategic Metals. (Available on SEDAR).
STRATEGIC METALS LTD, May/2016. Assessment Report #096829 by J. Morton.
TRIFECTA GOLD LTD, News Release. 19 Dec/2016, 13 Mar/2017, 26 Apr/2017, 15 Jun/2016, 16 Nov/2017.
TRIFECTA GOLD LTD, Web Site: www.trifectagold.com.
YUKON EXPLORATION AND GEOLOGY 2017, p. 51, 61.

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