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Occurrence Details


Occurrence Number
115I 126
Occurrence Name
Butter
Occurrence Type
Hard-rock
Status
Anomaly


General Information

Secondary Commodities: gold, copper
Aliases: Koo
Deposit Type(s): Porphyry Cu-Mo-Au
Location(s): 62.407220 N, -136.72 W
NTS Mapsheet(s): 115I07
Location Comments: Location marks center of BCGold copper soil anomaly.
Hand Samples Available at YGS: No
Last Reviewed: Apr 6, 2016

Capsule

Last Updated: Apr 6, 2016
Work History

Staked as Noon cl 1-108 (YA48868) in May/80 by United Keno Hill Mines Ltd which carried out geological mapping and soil sampling programs later in the year. In 1981 United Keno Hill Mines flew a regional airborne electromagnetic and magnetics survey over their claims holdings in the area including the Noon claims. Later in the year, the company carried out additional geological mapping and soil sampling programs. In 1982 the company dug 8 trenches on the Noon claims. 

Restaked as Butter cl 1-24 (YC46830) in Apr/2006 by S. Ryan who collected several lines of deep (~ 1 m) soil samples across the centre portion of the claim block. In Nov/2006 Ryan optioned the Butter claims and 14 other neighbouring claim groups to BCGold Corp in return for cash, shares and certain work commitments. 

In Apr/2007 the company added Butter cl 25-36 (YC60110) on the southeast side of the existing claim block. The company flew a regional airborne magnetic and radiometric survey over their claim holdings later in the year. In 2008 BCGold Corp collected 6 lines of Mobile Metal Ion (MMI) soil samples across the north-central portion of the Butter claim block.
 
In Jul/2010 BCGold accelerated the final payment under its property option agreement with Ryan and secured a 100% interest in the Butter and 15 other claim blocks optioned from Ryan. In Apr/2014 BCGold allowed the Butter claim block to lapse.
 
Restaked within Koo cl 1-12 (YF46501), cl 15-44 (YF46515) and cl 47-58 (YF46547) in Jul/2014 by B. Harris. 

Capsule Geology

The area is located on the southeast side of the eastern portion of Hoochekoo Creek approximately 6 km north of Copper North Mining Corp’s Carmacks Copper deposit (Minfile Occurrence #115I 008). Access is by helicopter or a 11 km ATV trail leading from the Carmacks Copper deposit.
 
The area is underlain by Late Triassic to Early Jurassic granodiorite assigned to the Granite Mountain batholith. The batholith intrudes Yukon-Tanana terrane basement rocks along its southwest margin and is faulted against Stikina rocks to the northeast along the Hoochekoo fault. To the northwest, the batholith is overlain by mafic to intermediate volcanic rocks of the Upper Cretaceous Carmacks Group and to the southeast; the Miller fault juxtaposes Carmacks Group volcanic rocks against the batholith. The Granite Mountain batholith is intruded by dacite dikes related to the Lower Cretaceous Mt. Nansen Group volcanics and by feeder dikes of the overlying Carmacks Group volcanic rocks. Broadly, the batholith is composed of a western Early Jurassic Long Lake suite part and an eastern latest Triassic to Early Jurassic Minto suite part; the contact between the two is poorly understood.
 
 Rock exposure on the Butter claims is estimated to be less than 5%. Based on previous exploration programs the Butter claims are underlain by foliated to non-foliated hornblende-biotite granodiorite. Scattered dacite dikes cut the granodiorite.  
 
Minor malachite staining on the surface of dacite dykes cutting moderately foliated granodiorite was noted in several locations by United Keno Hill Mines exploration personnel. Soil sampling carried out by the company identified numerous small spot copper anomalies across the Noon claim block. Follow-up trenching of the strongest anomalies failed to discover any mineralization. 

Ryan staked his initial claims to cover a magnetic high. Deep soil sampling analyzed by conventional inductively coupled plasma - mass spectrometry (ICP-MS) analysis failed to detect any anomalies. Ryan blamed the poor results on the presence of deep overburden.

MMI soil sampling completed by BCGold in 2008 outlined a 450 m northwest trending copper Mobile Metal Ion (MMI) soil anomaly centered in the northwest portion of the claim block. Scattered weak gold values occur within the anomaly. The occurrence location marks the approximate center point of the anomaly which appears to lie over a magnetic low that is flanked by magnetic highs at each end.
 
Harris has not yet undertaken any assessment work on his Koo claims. 
 

Location Map

Last Updated: Apr 6, 2016

Work History

Year Work Type Comment
2008 Geochemistry: Soil Using Mobile Metal Ion technology.
2007 Airborne Geophysics: Radiometric Also flew magnetics.
2006 Geochemistry: Soil Collected at depth.
1982 Trenching: Mechanical On Noon claims using bulldozer.
1981 Geochemistry: Soil On Noon claims.
1981 Geology: Bedrock Mapping On Noon claims.
1981 Airborne Geophysics: Electromagnetic Also flew magnetics.
1980 Geochemistry: Soil On Noon claims.
1980 Geology: Bedrock Mapping On Noon claims.

Regional Geology - Terrane

Group: Intermontane
Affinity: W Laurentia
Name: Stikinia
Realm: peri-Laurentian


Regional Geology - Bedrock

Supergroup:
Group/Suite: Minto
Formation:
Member:
Terrane:
Period Max: Triassic
Age Max: 204 MA
Period Min: Jurassic
Age Min: 195 MA
Rock Major: granodiorite/diorite
Rock Minor:
Reference: Tempelman-Kluit (1984) - GSC OF 1101
Geological Unit (1M): LTrEJM
Geological Unit (250K): LTrEJgM

Assessment Reports that overlap occurrence

Report Number Year Title Worktypes Holes Drilled Meters Drilled
095209 2008 2008 Geochemical Report on the BUTTER Property Soil - Geochemistry
093083 1992 Biophysical Assessment Report of Williams Creek Silt - Geochemistry, Water - Geochemistry, Data Compilation - Pre-existing Data, Biophysical Mapping - Studies, Environmental Assessment/Impact - Studies, Heritage/Archeological - Studies
090929 1981 1981 Geological and Geochemical Report on the NOON Claim Group Electromagnetic - Airborne Geophysics, Magnetic - Airborne Geophysics, Soil - Geochemistry, Regional Bedrock Mapping - Geology, Petrographic - Lab Work/Physical Studies, Line Cutting - Other
090775 1980 1980 Geological and Geochemical Report on the NOON Claim Group-Hoochekoo Creek Area Rock - Geochemistry, Soil - Geochemistry, Bedrock Mapping - Geology, Line Cutting - Other
061099 1974 Geophysical and Geochemical Report on the BAY Claims Soil - Geochemistry, EM - Ground Geophysics, IP - Ground Geophysics, Resistivity - Ground Geophysics
061111 1971 Report on Geochemical Soil and Magnetometer Survey - BAY Claims Soil - Geochemistry, Bedrock Mapping - Geology, Magnetics - Ground Geophysics, Line Cutting - Other

Related References

Number Title Page(s) Document Type
YEG2009_11 Bedrock geology of southwest McQuesten (NTS 115P) and part of northern Carmacks (NTS 115I) map area p. 159-184. Annual Report Paper
2006-1 Tectonic assemblage map of Yukon-Tanana and related terranes in Yukon and northern British Columbia (1:1 000 000 scale) Open File (Geological - Bedrock)
YEG2015_13 Copper-gold ± silver mineralization at the Stu occurrence, central Yukon (Yukon MINFILE 115I 011) p. 207-222. Annual Report Paper
YEG2003_21 Early Jurassic porphyry(?) copper (-gold) deposits at Minto and Williams Creek, Carmacks Copper Belt, western Yukon p.289-303. Annual Report Paper
YEG1981 Yukon Exploration and Geology 1981 p. 217-218. Annual Report
YEG1982 Yukon Exploration and Geology 1982 p. 202-203. Annual Report
YEG2007_OV Yukon Exploration and Geology Overview 2007 p. 25. Annual Report
YEG1979_80 Yukon Geology and Exploration 1979-80 p. 262-263. Annual Report
Citations
BCGOLD CORP, Apr/2016. Web Site: www.bcgoldcorp.com.
BCGOLD CORP, News Release. 27 Nov/2006, 13 Aug/2007, 24 Jun/2008, 12 Jul/2010.
BCGOLD CORP, Oct/2009. Assessment Report # 095209 by G. Newton.
RYAN, S. Oct/2007. Assessment Report #094844 by S. Ryan.
TEMPLEMAN-KLUIT. D.J., 1984. Geology, Laberge (105E) and Carmacks (115I), Yukon Territory. Geological Survey of Canada, Open File 1101, 1:250 000 scale.

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