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Occurrence Details


Occurrence Number
105J 030
Occurrence Name
Marylou
Occurrence Type
Hard-rock
Status
Prospect


General Information

Secondary Commodities: copper, lead, molybdenum, silver, tungsten, zinc
Aliases: Bishop
Deposit Type(s): Skarn Pb-Zn
Location(s): 62.111110 N, -130.451110 W
NTS Mapsheet(s): 105J01
Location Comments: 1 Kilometres
Hand Samples Available at YGS: No

Capsule

Work History

Staked as 328 Marylou cl (YA45065) in Aug/79 by Getty Can Mls L, which performed mapping and geochem sampling in 1980. Restaked as 22 Uno claims (YB49293) in June and Sep/94 by Cash Resources Ltd. Cash Resources carried out a week of prospecting and soil and rock sampling on the claims in Aug/94.

Capsule Geology

Massive pyrrhotite and pyrite with lesser galena and sphalerite and rare chalcopyrite, arsenopyrite and molybdenite occur in pods up to 5 m long in three semiconformable sericitized shear zones which cut a 12 m thick calc-silicate bed. Minor scheelite is present in podiform bodies and layers up to 1 m thick in a 10 m thick section of diopside calc-silicate.
Scheelite, with associated lenses of pyrrhotite and sphalerite, is mostly restricted to hedenbergite-rich skarns whereas more distal garnet and wollastonite-rich skarns are unmineralized. The calc-silicate rocks and skarns strike 120° and dip 45° north, and form part of a sequence of hornfelsed Cambro-Ordovician clastic sedimentary rocks near the contact of a 400 m wide porphyritic biotite quartz monzonite dyke of Cretaceous age. A chip sample assayed 454 g/t Ag, 1.0% Cu, 5.0% Pb and 2.0% Zn across 2 m.
The Uno claim block is located on the southeast edge of the Selwyn Basin geological terrane. A major thrust fault separates Cambrian to Ordovician Road River Group sediments from allochthonous paracratonic rocks of the Cassiar Platform located approximately 1 km to the south. The claims lie in the upper plate of a southwest-dipping thrust fault that surfaces 2 km north of the claim block. The thrust fault is truncated downdip by a regional-scale high angle fault located 1 km south of the claims. Both faults strike approximately parallel to the axial fold trend.
Road River Group which underlie the claims, consists of thin to thick interbedded, maroon, rusty weathering pelitic hornfels; white to grey-blue, buff and rusty weathering quartzite; and grey to pale green, thinly laminated chert. Carbonate rocks are typically interbedded with chert and consist of thin bedded, strongly bleached, white to pale green calc-silicate hornfels with local skarn zones.
A Mid-Cretaceous elongate stock 2.5 km long and up to 300 m wide trends east-west across the property. Most of the stock is comprised of fresh non-foliated quartz-monzonite but in places grades into porphyritic biotite granite. The intrusion cuts obliquely across the strike of the sediments and generally exhibits sharp contacts. It produced a thermal metamorphic aureole, the extent of which has not yet been determined.
Two types of mineralization are present: 1) semi-massive to massive sulphide lenses and breccia fillings; and, 2) sulphide stockworks. Both are best developed within moderate to strongly bleached quartzite beds. Veins and skarn zones are also present but appear to be small and sporadically mineralized.
Massive sulphide lenses contain coarse-grained pyrite>galena>arsenopyrite>chalcopyrite>sphalerite>pyrrhotite. A 1 m chip sample collected previously by Getty Mines returned 633 g/t Ag, 12.5% Pb, 1.05% Cu, 0.18% Zn and only minor Au. Float boulders of similar mineralization collected by Cash Resources in 1994, assayed up to 853 g/t Ag, 18.7% Pb, 4.50% Zn, 1.66% Cu and 400 ppb Au.
The sulphide stockwork is also occurs in quartzite. Sulphide-filled fractures comprise 20 - 39% (by volume) of the mineralized stockwork and contain coarse-grained pyrite>galena>sphalerite>chalcopyrite>arsenopyrite>pyrrhotite. Outcrop samples collected by Cash Resources from the West Zone returned up to 289 g/t Ag, 7.35% Pb, 0.12% Zn, 0.09% Cu and low Au values (5 ppb) while float samples collected by Getty Mines and Cash Resources from the East Zone yielded up to 73.0 g/t Ag, 1.42% Pb, 2.72% Zn, 0.26% Cu, and low Au values (<5 ppb).
Cash Resources collected the majority of their soil samples on the east side of the cirque located in the east-central part of the property where previous work by Getty outlined a strong Ag-Pb-Zn-Cu anomaly. Soil geochemistry outlined a moderate, 450 by 150 m northwest-trending, Au anomaly coincident with the northern edge of the stock. Relatively uniform, moderately to strongly anomalous Cu response occurs over the granitic stock. Five soil samples collected off grid lines in gullies suspected of containing vein faults returned strongly anomalous values for Ag-Pb-Zb-Cu but near background response for Au. Individual values were as high as 175 ppm Ag, >10 000 ppm Pb, >10 000 ppm Zn, 300 ppm Cu and 17 ppb Au.

References

ARCHER, CATHRO & ASSOCIATES (1981) LTD, Jun/95. Assessment Report #093303 by W. Wengzynowski.

GETTY CANADIAN METALS LTD, 1980. Assessment Report *#090704 by S. Clemmer.

WEST, T., Apr/81. Petrology and Mineralogy of the Bishop Showing, Traffic Mountain, Yukon Territory. Unpublished B.Sc. Thesis, Carleton University.

YUKON GEOLOGY AND EXPLORATION 1979-80, p. 194.

Location Map

Last Updated: Sep 15, 2011

Work History

Year Work Type Comment
1994 Geochemistry: Rock
1994 Other
1994 Other
1980 Geology: Bedrock Mapping
1980 Other

Regional Geology - Terrane

Group: Ancestral North America
Affinity: W Laurentia
Name: North America - basinal strata
Realm: Laurentia


Regional Geology - Bedrock

Supergroup:
Group/Suite:
Formation: Rabbitkettle
Member: Twopete
Terrane: Laurentia
Period Max: Cambrian
Age Max: 500 MA
Period Min: Ordovician
Age Min: 472 MA
Rock Major: chert/siltstone/phyllite/limestone/conglo
Rock Minor: flow/breccia/tuff/slate
Reference: Gordey (1996) - GSC Map 19-1987, sheet 1
Geological Unit (1M): COR
Geological Unit (250K): COR1

Assessment Reports that overlap occurrence

Report Number Year Title Worktypes Holes Drilled Meters Drilled
090704 1979 Geological, Geochemical and Prospecting Report for Marylou 1-96 Claims Rock - Geochemistry, Silt - Geochemistry, Soil - Geochemistry, Prospecting - Other

Related References

Number Title Page(s) Document Type
ARMC007552 Map - Pike Lake copper district Geoscience Map (General)
ARMC016667 Geologic, geochemical showings, assay and claim group map of sheet 105J/1 - Pelly Lakes Geoscience Map (General)
ARMC016666 Geochemical results map - 105J/1 - Pelly Lakes Geochemical Map
ARMC017631 Topographic map of Pelly Lakes showing geology and sample sites - Anerd map Geoscience Map (General)
ARMC016665 Geochemical sample stations map - 105J/1 - Pelly Lakes Geochemical Map
ARMC016329 Geochemical values map - Cu, Pb, Zn - 105J/1 Pelly Lakes - MacMillan project Geochemical Map
BROCK000016 Geology map with handwritten notes and markings - Pelly Lakes North area Geoscience Map (Geological - Bedrock)
Citations

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