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Occurrence Details


Occurrence Number
115K 111
Occurrence Name
Hailstorm
Occurrence Type
Hard-rock
Status
Anomaly


General Information

Secondary Commodities: gold
Deposit Type(s): Vein Au-Quartz
Location(s): 62.057280 N, -140.162440 W
NTS Mapsheet(s): 115K01
Hand Samples Available at YGS: No

Capsule

Regionally, the area is underlain by equigranular biotite- and hornblendebearing granitoids and leucocratic aplite dykes of inferred Early Cretaceous age, comprising the Nisling Range batholith. In general, the Nisling Range batholith varies from non-magnetic granitic compositions in the west to magnetic dioritic compositions further east. Porphyritic dykes are locally noted nearby cutting the Nisling Range granitoids; these dykes may be Cretaceous in age, or may correspond with nearby Early Tertiary intrusive ages documented by Murphy (2011).

The Nisling Range batholith intrudes Snowcap and Finlayson assemblage rocks of the Yukon Tanana terrane (YTT). In the area, the Snowcap assemblage is dominated by siliceous meta-clastic rocks (quartz-biotite and quartz-muscovite schists). Subordinate marble and carbonaceous meta-clastic rocks likely correlate with the Finlayson assemblage.

The Hailstorm zone is marked by large sub-angular to sub-rounded granitic boulders along a rounded NW-SE trending ridge, approximately 1.5km from the northern edge of the Nisling Range batholith. Host rocks comprise a black and white biotite-hornblende-granodiorite with up to 10% sheeted quartz veining. The granodiorite is predominantly unaltered, with only localized zones of weak argillic alteration of plagioclase and chlorite after biotite and hornblende. Chlorite-clay veinlets are also present in some zones, with associated iron-carbonate (ankerite?) and trace pyrite. Mineralization is hosted within the sheeted quartz veins, and includes pyrite, chalcopyrite plus malachite, arsenopyrite, molybdenite and rare visible gold. Disseminated molybdenite and pyrite are also observed in some samples. Overall sulphide concentrations are low (<0.1%), but locally reach 1- 2% in select samples. Quartz veins are on average 1-4mm wide, with an average spacing of 10- 20cm. Locally wider (5-15cm) smoky grey to milky white quartz veins were also observed in the granodiorite, but no sulphides were observed in hand sample of these veins.

Prospecting in 2012 returned values of 1.7 g/t Au, however diamond drilling confirmed only weak to moderate sheeted quartz and quartz-chlorite veining.
(AR 09662), (AR 96330)

Location Map

Last Updated: Oct 29, 2019

Work History

Year Work Type Comment
2013 Drilling: Diamond
2012 Geochemistry: Rock
2012 Geochemistry: Soil
2012 Geology: Bedrock Mapping
2012 Ground Geophysics: IP
2012 Ground Geophysics: Magnetics
2011 Drilling: Diamond
2011 Geochemistry: Rock
2011 Geochemistry: Soil

Regional Geology - Terrane

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Regional Geology - Bedrock

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Age Max: MA
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Assessment Reports that overlap occurrence

Report Number Year Title Worktypes Holes Drilled Meters Drilled
096662 2013 Assessment Report on the 2013 Diamond Drilling and Geochemical Sampling on the Wolf Project Diamond - Drilling, Drill Core - Geochemistry, Soil - Geochemistry 8 1623.10
096330 2012 Assessment Report on the 2012 Geochemical Sampling, Geological Mapping and Ground Geophysics on the Wolf Project Soil - Geochemistry, Bedrock Mapping - Geology, IP - Ground Geophysics, Magnetics - Ground Geophysics, Line Cutting - Other
095754 2011 Assessment Report on the 2011 Geochemical Sampling and Prospecting on the Wolf Property Rock - Geochemistry, Silt - Geochemistry, Soil - Geochemistry, Prospecting - Other

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