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Occurrence Details


Occurrence Number
105F 131
Occurrence Name
Ukon Showing 1
Occurrence Type
Hard-rock
Status
Showing


General Information

Primary Commodities: rare earths, niobium
Secondary Commodities: uranium
Aliases: Guano
Deposit Type(s): Skarn
Location(s): 61.498440 N, -132.415480 W
NTS Mapsheet(s): 105F08
Location Comments: Georeferenced from Map 14 in AR 095343 (p. 625).
Hand Samples Available at YGS: No

Capsule

Work History

Staked as Guano, etc. cl (YA00242) in Jul-Sep/76 by Ukon Joint Venture (Chevron and Kerr Addision), which explored with mapping, geochemical sampling and radiometric surveys in 1976. Restaked as PS cl (YB00978) in Aug/87 by Mountain Province Mining Inc which sampled the area, taking contour soil samples downslope of the occurrence and one rock sample in an undisclosed location. In 2003, True North Gems soil sampled in the vicinity of the occurrence. In 2009, True North Gems undertook rock sampling. In 2010, Great Western Minerals carried out a property-wide airborne radiometric & magnetic survey over the property and completed soil lines over the occurrence and to the north of it.

Regional Geology
 
The occurrence is located on the Cassiar Platform, a curvilinear shelf that formed in the early Paleozoic, roughly parallel to the western margin of the North American craton but separated from it by the Selwyn Basin. Shallow marine miogeoclinal sediments were emplaced on the platform until Late Devonian time. Block faulting and local uplift during the Late Devonian and Mississippian resulted in deposition of carbonaceous shale and chert pebble conglomerate in the Selwyn Basin and across the platform. Local explosive volcanism produced volcaniclastic material and flows of the Pelly Mountains volcanic belt. The belt comprises localized submarine volcanic centres generated in an extensional environment that are separated by basins in-filled with sediments and volcaniclastic rocks. Several cogenetic syenite and trachyte domes and small stocks are the remains of vent areas. Subsequent deformation is a result of Mesozoic thrust faulting related to the Cordilleran orogeny, emplacement of Cretaceous intrusions and Tertiary strike-slip movement along the major northwest-trending Tintina Fault, 30 km to the northeast.

Property Geology
 
The occurrence is hosted in metasomatized Silurian-Devonian Askin Group carbonates. (It is showing #1 in AR 090269). Chip sampling of the metasomatized carbonate rocks yielded 0.49% total rare earth oxides over 1.0 m. A 30-m-long metre-thick radioactive dyke crosscuts the carbonate and skarn. This resistant east-west trending dyke is fine-grained, green-grey with narrow red/pink bands and quartz veinlets, and numerous carbonate-rich fragments. Despite the high radioactivity, chip sampling of the dyke only returned 0.033% U3O8. Chip sampling of a dyke 24 m south of the main dyke yielded 1.53% total rare earth oxides, 1.33% ZrO2 and 0.25% Nb2O5 over 0.2 m (AR 095343).

Location Map

Last Updated: Mar 12, 2020

Work History

Year Work Type Comment
2010 Airborne Geophysics: Gamma-Ray Spectrometry
2010 Airborne Geophysics: Magnetic
2010 Geochemistry: Soil
2009 Geochemistry: Rock
2003 Geochemistry: Soil
1987 Geochemistry
1976 Airborne Geophysics
1976 Geochemistry
1976 Geology

Regional Geology - Terrane

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Regional Geology - Bedrock

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Related References

Number Title Page(s) Document Type
YEG1979_80-pg55 Rare earth elements in the Guano-Guayes skarn property Pelly Mountains, Yukon Territory Annual Report Paper
1979Chronic Geology of the Guano-Guayes rare earth element bearing skarn property, Pelly Mountains, Yukon Territory MSc Thesis
MIR1976 Mineral Industry Report 1976 Annual Report
Citations

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