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Occurrence Details


Occurrence Number
116B 204
Occurrence Name
Classic Deposit
Occurrence Type
Hard-rock
Status
Deposit


General Information

Primary Commodities: gold
Aliases: Brewery Creek
Deposit Type(s): Epithermal Au-Ag: Low Sulphidation, Porphyry-related Au
Location(s): 64.0260 N, -138.2140 W
NTS Mapsheet(s): 116B01
Location Comments: Location from satellite imagery and company location map
Hand Samples Available at YGS: No

Capsule

Cretaceous (91 Ma) Tombstone Suite monzonite and quartz monzonite intrudes Paleozoic Earn and Road River Groups lithologies as a series of semi-conformable sills along a 15km strike length defining the Brewery Creek Reserve Trend.  Younger, Tombstone Suite syenite and biotite monzonite occur locally in the south-central portion of the property.  All compositional phases of the Tombstone Suite intrusives are known to host gold mineralization.

Sill emplacement is primarily controlled by a tectonized, graphitic argillite at the contact between the Earn and Road River Groups.  This contact is also the locus of NNE-directed thrust faulting that has placed thin (<150 m thick) sequences of Silurian siltstone against Devonian siliciclastic rocks.  The age of faulting is probably related to earlier Mesozoic compression along the Dawson, Tombstone and Robert Service Thrust Faults and the closing of the Selwyn Basin.

Brewery Creek deposits exhibit characteristics of both epithermal type and intrusive-related gold systems. It is generally considered to be an alkalic intrusion-associated gold deposit, as most of the mineralization is concentrated within or proximal to the monzonites of the Cretaceous Tombstone Suite.  Gold mineralization occurs in fracture-controlled quartz stockwork in both siliciclastic and intrusive rocks along an east-northeast striking, moderately south dipping structural trend known as the Brewery Creek Reserve Trend. 

Altered intrusive rocks are typically the preferred host for gold mineralization, however gold mineralization at the Pacific deposit exhibits a strong preference for a siltstone host, and in other deposits into adjacent intrusive rocks.  Major ore-controlling structures in intrusive rocks are related to a post Tombstone age, NNW compressional event that produced ESE and NE striking conjugate shears and ENE listric normal faulting localized along graphitic argillite/intrusive sill contacts. Approximately 85% of the mined ore was hosted by the various Cretaceous-aged quartz monzonite sills with the balance contained in silicified and brecciated Earn Group sediments.

The Classic zone is located approximately 3 km south of the main Brewery Creek Reserve Trend.  Discovered originally in 1991 (Hemlo Gold Mines Inc.-Loki Gold Corporation) by soil sampling.  Controls on mineralization in the Classic zone are poorly understood with current interpretation based on the underlying pluton and faulting. A large alkalic syenite intrusion hosts gold mineralization primarily in sheeted quartz/carbonate/pyrite+\-arsenopyrite veins and as fine-grained disseminations associated with pyrite. The deposit is defined by 52 RC drill holes and 17 core drill holes, totaling 13,478 m.  The mineralization lies entirely on the southwest side of the Classic Fault.  The zone is approximately 1400 m in length, 30 m wide, and 240 m down dip.

Location Map

Last Updated: Jun 28, 2021

Work History

Year Work Type Comment
2018 Drilling: Diamond
2018 Lab Work/Physical Studies: Metallurgical Tests
2011 Airborne Geophysics: Magnetic
2011 Drilling: Reverse Circulation 24 holes, 6,226 m
2011 Geochemistry: Drill Cuttings
1998 Geochemistry: Rock
1998 Lab Work/Physical Studies: Metallurgical Tests
1997 Development, Surface: Access Road
1997 Drilling: Reverse Circulation 11 holes, 1634 m
1997 Trenching: Mechanical
1994 Geochemistry: Rock
1994 Geochemistry: Soil
1994 Geology: Bedrock Mapping
1993 Drilling: Reverse Circulation 5 holes,
1993 Geochemistry: Drill Cuttings
1993 Geochemistry: Soil
1992 Geochemistry: Soil
1992 Ground Geophysics: IP
1992 Ground Geophysics: Magnetics
1992 Other: Line Cutting
1991 Development, Surface: Access Road
1991 Geochemistry: Soil
1991 Geology: Bedrock Mapping
1991 Other: Line Cutting
1991 Trenching: Mechanical
1990 Geochemistry: Soil
1990 Ground Geophysics: Magnetics

Regional Geology - Terrane

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Regional Geology - Bedrock

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Related References

Number Title Page(s) Document Type
093191 Drilling Report on the ELE, LEE, EEL, FLEE Claims Assessment Report
092928 Geological, Geochemical, Geophysical and Drilling Report on the LEE, EEL, ELE and FLEE Claims Assessment Report
093027 Geological, Geochemical, Geophysical and Drilling Report on the EEL, LEE, ELE, and FLEE Claims Assessment Report
096013 2011 Assessment Report on the Brewery Creek Property Assessment Report
093309 Assessment Report on the ELE, LEE, EEL, FLEE Claims Assessment Report
097210 Work Done on the Brewery Creek Property in the year 2018 Assessment Report
093820 Brewery Creek Project 1997 Geological, Geochemical, Trenching and Drilling Report on the BDM, EEL, FLEE, ELE, and LEE Claims Assessment Report
093962 Brewery Creek Project 1998 Geological, Geochemical, Trenching and Drilling Report on the BDM, EEL, FLEE, ELE, and LEE Claims Assessment Report
093078 Geological, Geochemical and Geophysical Report on the EEL Claims Assessment Report
Citations

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