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Occurrence Details


Occurrence Number
105O 007
Occurrence Name
Cynthia
Occurrence Type
Hard-rock
Status
Prospect


General Information

Secondary Commodities: antimony, arsenic, silver, gold, lead, bismuth, copper
Aliases: Art
Deposit Type(s): Plutonic Related Au, Vein Au-Quartz
Location(s): 63.387890 N, -131.354670 W
NTS Mapsheet(s): 105O06
Location Comments: Near mid-point of Intersection zone.
Hand Samples Available at YGS: No
Last Reviewed: Mar 28, 2014

Capsule

Last Updated: Mar 28, 2014
Work History

     *In Mar/2014 the occurrence location was moved approximately 1.5 km to the southwest to an area which returned the highest gold assays and where Golden Predator collared their diamond drill holes.  
 
Staked as Art cl 1-8 (Y14156) and cl 9-12 (Y14214) in Oct/67 by the Hess Project (Atlas Explorations Ltd, Quebec Cartier Mining Company and Phillip Brothers (Canada) Ltd), which conducted grid soil sampling, magnetic and electromagnetic ground surveys in 1968.

Restaked as Emmy cl 1-16 (YA75914) in Sep/81 by Union Carbide Canada Ltd. The company re-assayed stored samples from the area and carried out a reconnaissance prospecting and silt sampling program in early July before staking the claims. The following year the company carried out a geological mapping and rock sampling program on the claims.
 
Restaked as Hess cl 1-64 (YB18664) by Noranda Exploration Company Ltd in Aug/91. It appears that the company did not carry out any assessment work and the claims were allowed to expire the following year.

Restaked within EM cl 1-106 (YB44695) and cl 107-112 (YB64001) in May/95 by B. Lueck. The claims were subsequently optioned to Yukon Gold Corp which carried out mapping and rock and soil sampling later in the summer.

Sometime in 1997, Yukon Gold sold its interests to Alliance Pacific Gold which in turn optioned the claims in Jun/97 to Cyprus Canada Inc. Cyprus Canada carried out a helicopter reconnaissance program later that year. Cyprus Canada dropped its option in Jun/98 and returned the claims to Alliance Pacific Gold.

Restaked as Cynthia cl 1-50 (YC10257) in Jun/2002 by Klad Enterprises Ltd which added cl 11-28 (YC10730) in Jul/2002, cl 29-38 (YC10710) in Aug/2002 and cl 39-50 (YC10764) in Nov/2002. The company carried out a reconnaissance scale exploration program in late June to early Jul/2002 followed by a more detailed program in late July to early August/2002. In Nov/2007 the claims were transferred to 18526 Yukon Inc. During 2009 various Cynthia claims were allowed to lapse. At the end of 2009 the Cynthia property was comprised of 35 claims in good standing.
 
In 2009 18526 Yukon Inc carried out a ground based total field magnetics and VLF-EM survey over the Intersection zone, an area where several high grade gold bearing rock samples had been collected.
 
In Jun/2010 18526 Yukon Inc surrounded the remaining 35 Cynthia claims with C cl 1-4 (YD61677) and cl 5-184 (YD61801). In Jul/2010 Golden Predator Corp optioned a 100% interest in the Cynthia and C claims in return for cash, shares and certain work commitments. Later in the summer the company carried out a detailed geological mapping program over the Intersection zone the results of which were used to locate a 7 hole (1 099.77 m) diamond drill hole program.
 
In 2011 Golden Predator carried out reconnaissance exploration on the property.
 
Capsule Geology


The area is located northwest of Niddery Lake and the Hess River and south of Emerald Creek in northeast central Yukon. Although the area has not yet been remapped by the Yukon Geological Survey, Gordey and Makepeace (2003) of the Geological Survey of Canada released a geological compilation of the Yukon which covers this area. According to Gordey and Makepeace the area lies in the northeastern end of the Selwyn Basin and is underlain by metasedimentary rocks ranging in age from Lower Cambrian to Permian.
 
The oldest rocks in the area are Lower Cambrian sedimentary rocks assigned to the Gull Lake assemblage. They are overlain by Ordovician to Devonian Road River black shales, chert and minor limestones. The Road River Group is overlain by Devonian to Mississippian Earn Group shales and metavolcanics. Unlike other geologists Gordey and Makepeace show a wedge of Carboniferous to Permian shales siliceous slate, siltstone, minor quartzite and limestone assigned to the Mount Christie Formation running through the centre of the occurrence area. At the eastern end of this wedge, Mississippian Keno Hill Quartzite occurs in two long thin bodies. This entire sequence of rocks is intruded by two Late Cretaceous granitic intrusions which are informally referred to as the Twin Batholiths. The two batholiths may actually be one batholith which outcrops in two areas.

The original occurrence location was located on the southeast side of the northern most batholith and covered anomalous copper, lead and zinc values in soil overlying Devonian to Mississippian Earn Group graphitic shale. The anomaly which was discovered on the Art claims by the Hess Project is likely related to the intrusion. The same Cretaceous intrusion has produced an area of locally pyritic hornfels on the west side of the Art claims. High zinc and copper values are associated with the hornfels and an area of fairly intense quartz veining in black chert.
 
Union Carbide restaked the area to cover gold and silver stream sediment anomalies and located a pyrite-arsenopyrite vein from which specimens assayed up to 3 130 ppb gold, 775 ppm silver, 2 618 ppm arsenic, 795 ppm antimony, 375 ppm bismuth and 1.7% lead. Breccia zones adjacent to the vein returned gold values up to 660 ppb, and a specimen of black chert breccia with visible galena assayed 3.7% lead and 948 g/t silver. However, most samples returned values of less than 160 ppb gold and 6 ppm silver.Lueck staked the EM claims for their potential to host "Fort Knox type" (more commonly called intrusion related) mineralization. Cecile (Open File 1118) mapped a large contact metamorphic aureole between the metasedimentary rocks and surrounding the batholiths.
 
Work carried out by Yukon Gold identified an area of anomalous results between the two batholiths. The area is comprised of brecciated argillite and was previously identified by Union Carbide. Five grab samples returned up to 628 ppb gold and 1.4 ppm silver. Sample descriptions were not reported but likely comprise quartz veins containing pyrrhotite, pyrite and bismuthinite +/- galena and chalcopyrite in hornfelsed argillite. Additional grab samples and a line of soil samples collected westward across the claim group returned anomalous gold values up to 70 ppb.
 
In 1997 Cyprus Canada resampled the hornfelsed sedimentary rocks located between the two batholiths. A grab sample collected in the same area and consisting of quartz feldspar dyke containing 2 - 8 % pyrrhotite returned 1.8 g/t gold. Eight other samples collected throughout the hornfelsed sediments returned between 0.5 and 1 g/t gold.

Klad Enterprises explored their claim block in an effort to pinpoint the source of various gold-in-silt anomalies reported by the Geological Survey of Canada. Geological mapping and sampling outlined three areas of mineralization. The Ted zone lies overtop a series of north-northeast trending faults that trend along the eastern side of both batholiths. The zone hosts several quartz-feldspar porphyry dykes and numerous chalcedony and druzy quartz veins as well as intensive quartz stockworks. Chalcedony veins located in the northern half of the zone return values as high as 2.56 g/t gold. Chalcedony veins and pervasively silicified material located in the southern half of the zone returned values up to 1.24 g/t gold over 0.9 m and 1.25 g/t gold over 1.1 m. The Ted zone shows a strong enrichment in arsenic as arsenopyrite and pyrite is wide spread.
 
The Gary zone trends west northwest through the centre portion of the Cynthia claim block, across the northeast end of the southernmost batholith. The zone host numerous dyke swarms, intensive quartz stockworks and thicker linear veins with minor chalcedony veining. Sampling of the dike swarms along the southeast end of the zone returned values up to 296 ppb gold. The west-northwest end of the zone returned generally lower results although anomalous values up to 679 ppb gold were reported. The quartz stockwork bears low-sulfide gold mineralization associated with minor fine-grained pyrite and trace arsenopyrite.
 
The Intersection zone is a 1.5 by 1.5 km area, located northeast of the southernmost batholith, marks the mutual intersection between the Ted and Gary zones. This zone is characterized by intensive fracturing, brecciation and the highest density of quartz stockwork on the claim block. The area also contains the strongest silicification and hydrothermal alteration and hosts the highest gold grades. Gold grades range from 1.0 to 4.0 g/t gold, with one sample returning 16 g/t gold. Gold mineralization is hosted by both high arsenic and low sulphide assemblages and grades are higher than either of the respective assemblages hosted by the Gary or Ted zones. The Intersection zone also hosts a third mineral assemblage, consisting of a highly sulphidized, highly arsenical gold-rich assemblage that also contains high silver (up to 479 g/t), lead (up to 3 100 ppm), bismuth (up to 780 ppm) and antimony (up to 6 720 ppm). This set of mineral assemblages suggests an epithermal affinity to the mineralization. Structural observation of the Intersection zone suggests a southeast plunge. At the end of Klad’ s exploration program the property was considered “drill ready”.
 
     *In Mar/2014 the occurrence location was moved approximately 1.5 km southwest from its original location to an area which returned the highest gold assays and where Golden Predator collared their diamond drill holes.
 
The 2009 ground based total field magnetics and VLF-EM survey was centred over the Intersection zone and included the occurrence location. This area is historically known to contain the highest assayed gold mineralization on the property. The survey found a generally poor correlation between areas of low magnetic field strength and crossovers in inphase and quadrature of the VLF response, although several areas of magnetic lows likely representing mineralized quartz veining and stockworks were identified.
 
Golden Predator focused their exploration program on the Intersection zone. The company carried out a geological mapping program focused on structural geology prior to commencing the diamond drill program. The drill program was designed to test mineralized zones hosted by structural corridors.  The first three holes (DD-CY10-01, 02 and 03), were directed toward a prominent northwest-trending shear zone containing a quartz porphyry dyke in its hanging wall. Drillhole 01 intersected 1.5 m of 1.31 g/t gold; the second hole (02) returned similar results. Drillhole 03 returned 14 m of 0.70 g/t gold. The four remaining holes targeted extensions of the shear zone as well as an area of intense silicification. All holes intersected strong alteration.






Location Map

Last Updated: Mar 28, 2014

Work History

Year Work Type Comment
2011 Other: Property Evaluation Carried out reconnaissance exploration program.
2010 Drilling: Diamond Seven holes (1,099.7 m) tested Intersection zone.
2010 Geology: Detailed Bedrock Mapping Mapped Intersection zone with emphasis on structural geology.
2009 Ground Geophysics: EM Also collected VLF and total magnetics data.
2002 Geochemistry: Rock Reconnaissance and detailed.
2002 Geochemistry: Soil Reconnaissance and detailed.
2002 Geology: Bedrock Mapping Reconnaissance and detailed.
1997 Geology: Bedrock Mapping Program was reconnaissance in nature.
1997 Other: Property Evaluation Program was reconnaissance in nature.
1995 Geochemistry: Rock Also collected soil samples.
1995 Geology: Bedrock Mapping
1982 Geochemistry: Rock
1982 Geology: Detailed Bedrock Mapping Mapped claim area.
1981 Geology: Bedrock Mapping
1981 Other: Prospecting
1981 Geochemistry: Silt Re-assays previously collected silt and rock samples.
1968 Geochemistry: Soil Grid based.
1968 Ground Geophysics: EM Also magnetics data collected.

Regional Geology - Terrane

Group: Ancestral North America
Affinity: W Laurentia
Name: North America - basinal strata
Realm: Laurentia


Regional Geology - Bedrock

Supergroup:
Group/Suite:
Formation: Mount Christie
Member:
Terrane: Laurentia
Period Max: Carboniferous
Age Max: 328 MA
Period Min: Permian
Age Min: 260 MA
Rock Major: chert/shale/siltstone
Rock Minor: quartzite/limestone/dolostone/barite
Reference: Cecile (unpub. 1997) - corrections to Cecile & Abbott (1989) - GSC OF 2076
Geological Unit (1M): CPMC
Geological Unit (250K): CPMC

Assessment Reports that overlap occurrence

Report Number Year Title Worktypes Holes Drilled Meters Drilled
095692 2010 Assessment Report, 2010 Diamond Drilling Program Cynthia Project Diamond Drilling, Detailed Bedrock Mapping Geology 7 1099.77
095671 2009 2009 Assessment Report for the Cynthia Property VLF and Magnetics Surveys July 12-16, 2009 EM Ground Geophysics, Magnetics Ground Geophysics
094432 2002 Assessment Report on the Cynthia Property Rock Geochemistry, Silt Geochemistry, Soil Geochemistry, Detailed Bedrock Mapping Geology
093827 1997 1997 Geological Assessment Report on Emerald Lake Claims Rock Geochemistry, Silt Geochemistry, Soil Geochemistry
093501 1995 Geological and Geochemical Assessment Report for the EM 1-106 and EM 107-112 Claims Rock Geochemistry, Silt Geochemistry, Soil Geochemistry, Detailed Bedrock Mapping Geology
091377 1982 The Geology of the Emmy Claims Orthophoto Airphotography, Bedrock Mapping Geology
019033 1968 Atlas Explorations Limited Project Report 1968 Hess River Area Silt Geochemistry, Soil Geochemistry, Regional Bedrock Mapping Geology
019809 1968 Hess Area Project Proposed Property Follow-Up 1968 Field Season Research/Summarize Pre-existing Data
018947 1967 Hess River Project Report Rock Geochemistry, Soil Geochemistry, Detailed Bedrock Mapping Geology
019032 1967 Hess River Project Report Data Compilation Pre-existing Data

Related References

Number Title Page(s) Document Type
ARMC001071 Hess River Area Geological Legend Miscellaneous Company Documents
ARMC008033 Geochemical results and claim group map of sheet 105-O-7 - Ross River Geochemical Map
YEG1982 Yukon Exploration and Geology 1982 166-167. Annual Report
YEG2002_23 Structural settings and geochemistry of the Cynthia gold prospect, Tintina Gold Belt, Hess River area (105O/6), Yukon 285-294 Annual Report Paper
YEG1996 Yukon Exploration and Geology 1996 25, 30. Annual Report
YEG2002_OV Yukon Mining, Development & Exploration Overview 2002 8, 24. Annual Report
YEG2010_OV Yukon Exploration and Geology Overview 2010 45, 58, 64. Annual Report
YEG2011_OV Yukon Exploration and Geology Overview 2011 34, 63. Annual Report
019044 Report on Geological, Geochemical and Geophysical Work Done During 1968 Field Season Assessment Report
094432 Assessment Report on the Cynthia Property Assessment Report
093827 1997 Geological Assessment Report on Emerald Lake Claims Assessment Report
091377 The Geology of the Emmy Claims Assessment Report
2003-9(D) Yukon Digital Geology (version 2) Open File (Geological - Bedrock)
019809 Hess Area Project Proposed Property Follow-Up 1968 Field Season Assessment Report
1989-3 Yukon Gold-Silver File Description of Occurrences Open File (Geological - Bedrock)
ARMC016466 Geology map overlay - 105O/6 Geoscience Map (Geological - Bedrock)
ARMC016465 Geology map overlay with claims marked - 105O/6 Geoscience Map (Geological - Bedrock)
ARMC015535 Map of Niddery Lake area with geological notations - 105O/6 Geoscience Map (General)
ARMC015533 Geochemical results and Claim group map of sheet 105-O-6 Geochemical Map
ARMC011933 Geochemical results and claim group map of sheet 105-O-6 - Ross River Geochemical Map
ARMC011934 Map of 105-O-6 showing geology Geoscience Map (Geological - Bedrock)
ARMC018191 Field sheet of 105O Niddery Lake with notations re: streams where silt samples have been taken Geoscience Map (General)
ARMC018192 Field sheet of 105O with notations Geoscience Map (General)
ARMC018193 Field sheet of 105O Niddery Lake with geology notations Geoscience Map (General)
ARMC015534 Correspondence with partial map of Niddery Lake with geochemical notations Miscellaneous Company Documents
BROCK000090 Geology map - Geochemical results and claim group map of sheet 105-O-6 - Fig. 19 Geoscience Map (Geological - Bedrock)
Citations
ALLIANCE PACIFIC GOLD CORP, 6/Aug/97. News Release.
BERDAHL, R., Apr/2010. Assessment Report #095671 by D. Torgerson.
CECILE, M.P. 1984. Geology Southwest and Central Niddery Lake Area, Yukon territory. Geological Survey of Canada, Open File 1118.
CECILE, M.P. and ABBOTT, J.G., 1989. Geology of the Niddery Lake Map Area (NTS 105 O), Geological Survey of Canada, Open File 2076.
GEOLOGICAL SURVEY OF CANADA, 1991: Open File 2364 (NTS 105O, Parts of 105P); Regional Stream Sediment and Water Geochemical Reconnaissance Data, East-Central Yukon; Canada-Yukon Economic Programming Agreement (1989-1990).
GOLDEN PREDATOR CORP, Mar/2011. Assessment Report #095692 by T. Bourne and F. Marino.
GOLDEN PREDATOR CORP, News Release. 19 Jul/2010, 21 Apr/2011.

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