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Occurrence Details


Occurrence Number
115J 100
Occurrence Name
Shadow
Occurrence Type
Hard-rock
Status
Anomaly


General Information

Secondary Commodities: gold
Deposit Type(s): Porphyry-related Au
Location(s): 62.331940 N, -138.144720 W
NTS Mapsheet(s): 115J08
Location Comments: 1 Kilometres
Hand Samples Available at YGS: No

Capsule

Work History

Staked as Shadow cl (YA92672) in Jul/85 by Kerr Addison, which conducted mapping and geochem surveys later in the year, added additional claims in Jul/86 and performed geological mapping and prospecting later that year and in 1988.

Since 1988, soil sampling has been completed over the Shadow occurrence in 2010 and 2016.

Capsule Geology

The occurrences lies within a large, northwest trending rhyolite dyke swarm intruding andesite and volcanicsand a Mesozoic granodiorite body. The area around the occurrence to the south, southeast and west, is comprised of Cretaceous dacite volcanics. Further outside, a larger Jurassic age granodiorite body occurs to the west, southwest and south. Upper Cretaceous basalts overlie all units. Intensely silicified breccia and porphyry dykes occur along a major north-trending lineament.

The breccia varies from moderately to intensely silicified rhyolite porphyry fragments in a siliceous matrix. Some hematitic alteration was also noted. In more strongly silicified breccia, fragments are coated by cryptocrystalline, chalcedonic and radiating, drusy quartz. Later stage quartz and chalcedony veinlets cut the breccia. A clay-sericite Shadow Zone alteration zone with quartz stringers surrounds the Shadow Zone. West and north of Shadow, three other altered zones occur. Brecciation, quartz veining and/or silicification occur in areas up to l00m long and 15m vide. One zone is surrounded by a 130m wide area of moderate clay alteration, weak sericite and quartz stringers. 

Gold results are weak however values of 303 ppm As, 13.1 ppm Sb and 370 ppb Hg were encountered. 

Location Map

Last Updated: Oct 25, 2019

Work History

Year Work Type Comment
2016 Geochemistry: Rock
2016 Geochemistry: Soil
2010 Geochemistry: Soil
1988 Geochemistry: Soil
1988 Ground Geophysics: EM VLF-EM 16 survey.
1986 Geochemistry: Rock
1986 Geochemistry: Silt
1986 Geochemistry: Soil
1986 Geology: Bedrock Mapping 1:50 000 scale.
1985 Geochemistry: Rock
1985 Geochemistry: Silt
1985 Geochemistry: Soil
1985 Geology: Bedrock Mapping 1:50 000 scale.

Regional Geology - Terrane

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


Regional Geology - Bedrock

Supergroup:
Group/Suite:
Formation: Open Creek
Member:
Terrane:
Period Max: Cretaceous
Age Max: 85 MA
Period Min: Cretaceous
Age Min: 80 MA
Rock Major: dacite/flows/tuffs/basalt/dykes/sandstone
Rock Minor:
Reference: Tempelman-Kluit (1974) - GSC Map 16-1973
Geological Unit (1M): uKW
Geological Unit (250K): uKW

Assessment Reports that overlap occurrence

Report Number Year Title Worktypes Holes Drilled Meters Drilled
096947 2016 Assessment Report Describing Geochemical Sampling Soil - Geochemistry
096122 2010 Beringia Gold Corporation-Mineral Exploration Summary-Hay Project Soil - Geochemistry
092574 1988 Assessment Report-Shadow Claims 1-24-1988 Soil and VLF Surveys Soil - Geochemistry, EM - Ground Geophysics
091865 1986 Assessment and in House Report-Geological and Geochemical Report on the Shadow 1-24 Claims Rock - Geochemistry, Silt - Geochemistry, Soil - Geochemistry, Bedrock Mapping - Geology, Detailed Bedrock Mapping - Geology

Related References

Number Title Page(s) Document Type
ARMC006908 Geology map - Shadow M.C. Geoscience Map (Geological - Bedrock)
ARMC004708 Field notebook on Shadow claims VLF Miscellaneous Company Documents
ARMC004709 Field notebook on Shadow claims soil samples Miscellaneous Company Documents
ARMC004710 Sketch map on Shadow zone and Creek zone Geoscience Map (General)
ARMC004711 Field data on Shadow claims - Target 21 Miscellaneous Company Documents
ARMC010038 Shadow map - Contoured total field magnetics Geophysical Map
ARMC016552 Photo interpretation map - 115J/8 - Apex Mountain Geoscience Map (General)
ARMC016551 Geochemical map - 115J/8 - Apex Mountain Geochemical Map
ARMC016550 Geology map - 115J/8 - Apex Mountain Geoscience Map (Geological - Bedrock)
ARMC016553 Coloured geology map with notations - 115J/8 - Apex Mountain Geoscience Map (Geological - Bedrock)
Citations
Assessment Report #096947, Strategic Metals Ltd., by K. Willms, Oct/2016
YUKON EXPLORATION 1985-86, p. 362-363.
YUKON MINING AND EXPLORATION OVERVIEW 1988, p. 38.

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