Find publications, data and maps managed by the
Yukon Geological Survey

Occurrence Details


Occurrence Number
115J 017
Occurrence Name
Cockfield
Occurrence Type
Hard-rock
Status
Showing


General Information

Secondary Commodities: molybdenum, copper
Aliases: Co, Cofield, Dr, Iten, Kokup, Oke, Ray
Deposit Type(s): Porphyry Cu-Mo-Au
Location(s): 62.647780 N, -138.489440 W
NTS Mapsheet(s): 115J09
Location Comments: 1 Kilometres
Hand Samples Available at YGS: Yes

Capsule

Work History

The northwest edge of the property was partially staked as Ray cl (97882) in Jan/66 by Nordex EL, which performed a geochem survey later in the year. Staked in Jul/69 as CO cl (Y35756) by Newmont on the northwest end, and as DR and Patsy cl (Y35652) in Jul/69 by Dawson Range JV (Straus E Inc, Martin Marietta Corp, Molybdenum Corp of America, Trojan Cons M, and Great Plains Dev C of Can L) on the southeast end. Both groups were explored with mapping and geochem surveys later in the year.
In 1970, the CO group was optioned by United Keno E (United Keno Hill ML, Falconbridge and Can Superior EL), which explored with geochem and IP surveys and 6 drill holes (1479.5 m) and prepared a topographic map from airphotos in 1972.
Restaked as Cofield cl (YA7532) in Aug/76 and as Kokup cl (YA22201) in Aug/79 by Archer, Cathro & Assoc Ltd and optioned in 1980 by Denison ML, which performed mapping and a geochem survey. Cominco tied on the Battle cl (YA48695) in Apr/80 and carried out mapping and a geochem survey.
Archer, Cathro added OKE & Hen cl (YA92164) in Jun/85 and sold the property to Nordac Mg Corp, which optioned it briefly to Gyro Energy & Mls Corp. Nordac, which conducted mapping and geochem sampling in 1986, became Big Creek Res L in 1987.
The Hud & Barr cl (Y49181) were tied on to the south and east in Jan/70 by London Pride Silver ML. Kerr Addison ML tied on KOE cl (YA78417) to the southeast in Sep/83 and explored with mapping and geochem sampling in 1984 and 1985, VLF-EM surveys and hand trenching in 1985 and 5 holes (443.6 m) in 1986.
Walhala Exploration Ltd staked Bat cl (YB35850) northwest of Mt Cockfield in May/91. Both Noranda and Placer Dome visited the property in Aug/91 and took silt, soil and rock samples. This work was compiled for Walhala by Aurum Geological Consultants Inc. in 1992. Galleon Mining Ltd purchased a 20% interest in Walhala's assets in Dec/91.

Capsule Geology

Disseminations and veinlets of pyrite, chalcopyrite and molybdenite occur in a complex intrusive and volcanic setting. The mineralization is best developed in and around a small weakly altered quartz monzonite stock which cuts Paleozoic Nisling Terrane schist and Triassic Klotassin granodiorite at the head of West Battle Creek. The 1970 drilling indicated a fairly uniform grade averaging about 0.03% Cu and 0.013% Mo.
Cominco outlined a number of Cu-Mo anomalies associated with the stock. Chalcedonic quartz veins and clay-sericite-pyrite alteration occur along a major northwest-trending fault. Float from the fault zone is highly anomalous in gold, silver, antimony and arsenic.
The 1986 soil sampling by Nordac returned scattered anomalous gold values as high as 305 ppb, while Kerr Addison's trenches along the northwest-trending fault zone produced a few high values from fault breccia and drusy or massive quartz veins containing arsenopyrite.
Aurum's 1992 compilation shows a strong 500 x 1000 m copper anomaly (>500 ppm Cu) approximately 1.5 km west of Mt Cockfield, and a Noranda rock sample from the same area contained 42 ppb Au, 1035 ppm Cu and 314 ppm Mo.

References

COMINCO LTD, Dec/80. Assessment Report #090792 by A. Denton.

DAWSON RANGE JOINT VENTURE, 1970. Assessment Report *#061373 by R.J. Cathro.

DAWSON RANGE JOINT VENTURE, 1970. Assessment Report *#061124 by D.D. Rand.

DENISON MINES LTD, Mar/81. Assessment Report *#090767 by R.J. Cathro.

GYRO EXPLORATION AND MINING CORP., Dec/85. Engineer's Report by J.M. Dawson.

KERR ADDISON MINES LTD, Oct/84. Assessment Report *#091568 by H. Copland and D. Arscott.

KERR ADDISON MINES LTD, Jan/86. Assessment Report *#091725 by D. Arscott.

MINERAL INDUSTRY REPORT 1969-70, p. 64-68.

NEWMONT MINING CORPORATION OF CANADA LTD, 1969. Assessment Report *#060215 by C.P. Costin and W. Dolan.

UNITED KENO HILL MINES LTD, 1970. Assessment Report *#091346 by I.D. and R.E.V.

WALHALA EXPLORATION LTD, Jan/93. Assessment Report #093064 by R.A. Doherty.

YUKON GEOLOGY AND EXPLORATION 1979-80, p. 265-266.

YUKON EXPLORATION AND GEOLOGY 1984 (Open File).

YUKON EXPLORATION 1985-86, p. 361; 1987, p. 279.

Location Map

Last Updated: Aug 31, 2018

Work History

Year Work Type Comment
1991 Geochemistry: Soil Also rock and silt sampling.
1986 Geochemistry: Soil
1986 Geology: Bedrock Mapping
1980 Geochemistry: Soil
1980 Geology: Bedrock Mapping
1972 Drilling: Diamond Six holes, 1,397 m.
1972 Geochemistry: Soil
1972 Ground Geophysics: IP
1969 Geochemistry: Soil
1969 Geology: Bedrock Mapping
1966 Geochemistry: Soil

Regional Geology - Terrane

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


Regional Geology - Bedrock

Supergroup:
Group/Suite: Carmacks
Formation:
Member: upper
Terrane:
Period Max: Cretaceous
Age Max: 73 MA
Period Min: Cretaceous
Age Min: 68 MA
Rock Major: basalt, andesite
Rock Minor:
Reference: Ryan et al. (2013) - GSC CGM 116
Geological Unit (1M): uKC
Geological Unit (250K): uKC1

Assessment Reports that overlap occurrence

Report Number Year Title Worktypes Holes Drilled Meters Drilled
093064 1992 Geological and Geochemical Assessment Report on the Battle Mountain Property Historical Drill Core Geochemistry, Rock Geochemistry, Silt Geochemistry, Soil Geochemistry, Prospecting Other, Data Compilation Pre-existing Data
091924 1986 Report on Geochemical Survey-Mt. Cockfield Property-Mt. Cockfield, Y.T. Rock Geochemistry, Soil Geochemistry, Prospecting Other
090767 1980 Report on Geology and Geochemistry-Kokup 1-24 Claims Rock Geochemistry, Soil Geochemistry, Bedrock Mapping Geology, Prospecting Other
061124 1972 Photogrammetric Mapping-Dr and Patsy Claims Photogrammetry Remote Sensing
091346 1970 1970 Diamond Drill Statistics-Mount Cockfield Diamond Drilling, Drill Core Geochemistry 6 1397.20
061373 1970 Geological Mapping and Geochemical Sampling-Dr 1-64 and Patsy 1-8-Mt Cockfield Area Silt Geochemistry, Soil Geochemistry, Bedrock Mapping Geology, Prospecting Other
060215 1969 Geophysical and Geochemical Reports on the CO Claim Group Silt Geochemistry, Soil Geochemistry, Magnetics Ground Geophysics

Related References

Number Title Page(s) Document Type
ARMC004700 1986 program report on the Koe claims Report
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)
Citations

Drill Core at YGS Core Library

Number Property Year Drilled Core Size Photos Data
YK-86-01 Cockfield 1986 BQ 0 3
YK-86-02 Cockfield 1986 BQ 0 2
YK-86-03 Cockfield 1986 BQ 10 2
YK-86-04 Cockfield 1986 BQ 8 2
YK-86-05 Cockfield 1986 BQ 4 2

Submit Information to Yukon Geological Survey

Name:

E-mail:

Comment: