General Information
Primary Commodities: lead, silver, zinc
Secondary Commodities: titanium, barite, phosphorus
Deposit Type(s): Sediment hosted Sedimentary Exhalative Zn-Pb-Ag (Sedex)
Location(s): 62.784440 N, -135.143330 W
NTS Mapsheet(s): 105L14
Location Comments: .5 Kilometres
Hand Samples Available at YGS: Yes
Capsule
Work History
This occurrence was first staked in 1965 by Conwest Exploration Company Ltd, as part of a 734 claim block, following the discovery of the Faro orebody 80 km to the southeast. Limited prospecting, mapping, ground and airborne EM and magnetometer surveying was carried out. Reportedly, six EM anomalies were tested by diamond drilling and one of these drillholes intersected 0.45 m of massive pyrite. Due to a lack of understanding of the geological environment and geophysical character of other known deposits no significant mineralization was detected and the claims were allowed to lapse.
Restaked as Sue cl 1-1070 (80651) in Aug/74 by a syndicate of Conwest companies (Chimo Gold Mines Ltd, Consolidated Canadian Farday Ltd and International Mogul Mines Ltd) and Teck Corporation Ltd. U.S. Steel Western Hemisphere Inc acquired the Teck interest early in 1975 and formed the Macmillan Joint Venture. The joint venture carried out extensive bulldozer gridding, linecutting, EM, magnetometer and gravity surveying and geological mapping in 1975; additional gravity surveying in 1976 and 1977; drilled 17 holes (2,531 m) in 1978; MaxMin EM surveying, airstrip construction and drilling of 10 holes (2,481 m) in 1979.
Welcome North Mines Ltd tied on RSVP, PVA and Pelly cl (YA25299) in Aug/79 and optioned the claims to E and B Exploration Inc (Pelly Project), which carried out airborne magnetometer and EM surveying and geochemical sampling in 1980.
The Conwest syndicate's interest was acquired by Getty Canadian Metals Ltd in the spring of 1980 which staked various Get A, Get B, Get C and Get D claims (YA49085) in Jun/80 and carried out geological mapping, soil geochemical sampling, MaxMin EM and gravity surveying in 1980; EM and magnetometer surveying, soil and lake bottom geochemical sampling, prospecting and drilling of 3 holes (709.3 m) in 1981; linecutting, geochemical sampling, EM and gravity surveying and drilling of 3 holes (943.7 m) in 1982; linecutting, drilling of 69 overburden holes (531 m) and 2 diamond drill holes (2,045.5 m) in 1983; and diamond drilling of one hole (457.2 m) in 1984.
Most of the Sue claims surrounding the showing were subsequently abandoned and were restaked as Clear cl 1-490 (YB25815) in Jun/89 by Total Energold Corporation, which also purchased Conwest's NPI interest. Total Energold staked Clear cl 491-598 (YB27222) in April and May/90 and carried out geochemical soil and rock sampling and geological mapping to evaluated 18 target areas later in the year. The geochemical sampling included hand-augered soil samples and 35 samples of glacial overburden collected down-ice from the deposit using an overburden drill. The property was optioned to Mitsui Kinzoku Resources of Canada Inc, a wholly owned subsidiary of Mitsui Mining and Smelting Company Ltd in 1991. At the same time Total Energold purchased U.S. Steel's interest in the property.
Work carried out in 1991 consisted of diamond drilling of 19 holes (4,588.2 m), geological mapping, IP and gravity surveying, geochemical sampling, linecutting and trenching and staking of Clear cl 599-674 (YB36109) in Jul/91. In 1992 Total Erickson Resources Ltd, a wholly owned subsidiary of Total Energold carried out diamond drilling of 10 holes (3,100.1 m), geological mapping, soil geochemical sampling, trenching, linecutting and IP, gravity and Power Line magnetotelluric surveying.
The Clear and Sue claims were transferred to Energold Minerals Inc in Nov/92. In 1993, Mitsui and Energold carried out gravity and magnetometer surveying, auger assisted soil sampling, rock chip sampling, geological mapping and drilling of 6 holes (1,364 m). Baseline environmental studies were also carried out before Mitsui dropped its option. Energold Mining Ltd changed its name to Energold Drilling Corporation in Sep/2005.
2005-2010 not summarized yet.
A resource estimate was prepared by SRK Consulting for Copper Ridge Explorations Inc in February 2010.
Capsule Geology
The Clear Lake deposit is a proximal exhalative massive pyritic sulphide body within which drilling has outlined approximately 30 million tonnes of massive sulphides (mostly pyrite), including a geological reserve of 5,570,114 million tonnes grading 11.4% Zn, 2% Pb and 38.01 g/t Ag. The deposit is hosted by carbonaceous argillite, siltstone, chert and tuff of the Devonian to Mississippian Earn Group.
The property is bisected by the Tintina Fault. North of the fault are phyllite of the Lower Cambrian Mt Mye Formation and calcareous phyllite and limestone of the Cambrian to Ordovician Vangorda Formation. South of the fault are Ordovician to Lower Devonian Road River Group shale, and the Devonian to Mississippian Earn Group clastic rocks which host the Clear Lake deposit. Glacial overburden 5 to 26 m thick covers the property, and the geology is known mainly from drillholes and interpretations of geophysical surveys.
The main sulphide body was discovered in 1978 while drilling a 3 mgal residual gravity anomaly. The gravity anomaly coincides with magnetic and EM anomalies and is situated beside a small acidic lake containing geochemically anomalous lake bottom sediments. Lake bottom samples assayed up to 19,000 ppm Zn, 1.2 ppm Ag, and 20 to 40 ppm Cu. A subtle gossan was later recognized over the target.
The deposit is sigmoidal in shape, approximately 1 000 m long and up to 120 m wide, and pinches at depth. It dips steeply to the east, and Bouma sequences in drill core indicate that it is overturned. Sulphide minerals are laminated and consist largely of framboidal pyrite which is slumped and fragmented in places. The best drill intersection assayed 18.3% Zn, 2.15% Pb and 58.6 g/t Ag across 13 m. Tuffaceous rocks intercalated with the sulphides reach a thickness of 30 m in the original footwall, stratigraphically beneath the main massive sulphide lens. The tuff exhibits relict pyroclastic texture, with both matrix and fragments largely altered to soft grey clay, and local concretions of galena, sphalerite, barite, siderite and calcite.
Argillite which lies stratigraphically beneath the overturned footwall tuff is silicified to a depth of 90 m below the deposit. The overturned hanging wall is formed by a layer of argillite which is silicified so extensively it resembles mottled to laminated chert. Irregular pyrite stringers and masses are common throughout both the hanging wall and footwall argillite. Massive barite in several drillholes appears to be peripheral to the deposit and forms a partial cap over it. Barite and tuff lenses intersected at depth in the 1991 drillholes indicate that there is potential for another sulphide lens below the main orebody.
A trace element study of the tuffaceous rocks by Jim Morin of DIAND revealed high Ti and P contents and high K2O/Na2O ratios, consistent with an alkaline volcanic environment. The mineral deposit is inferred to be an exhalative deposit related to Devonian rifting. Worm tubes replaced by quartz and calcite surrounded and partly replaced by sphalerite and pyrite have been found in drill core, and the sulphides are believed to have precipitated from a hydrothermal fluid hotter than 350°C which mixed with cold seawater at a black smoker vent.
Soil sampling using hand augers and an overburden drill in 1990 located anomalies in several new areas. North of the Tintina Fault, stratiform galena and sphalerite outcrop at the transition between Mt Mye and the Vangorda Formation rocks, the same stratigraphic interval as the Faro deposits. Specimens from this area assayed up to 2.68% Zn, 0.78% Pb and 13.7 g/t Ag.
Drilling in 1992 showed that some gravity anomalies are due to bedrock highs adjacent to conductive graphitic shear zones which trend east-west through the main deposit. No new massive sulphide lenses were discovered.
A resource estimate was prepared by SRK consulting for Copper Ridge Explorations in February 2010. SRK estimates that the Clear Lake deposit contains 7.765 million tonnes of Inferred Mineral resource grading 1.08% Pb, 7.6% Zn and 22 g/t Ag at a 4% (Pb+Zn) cut-off, with Pb grades capped to 1.5% and Ag grades capped at 60 g/t.
This occurrence was first staked in 1965 by Conwest Exploration Company Ltd, as part of a 734 claim block, following the discovery of the Faro orebody 80 km to the southeast. Limited prospecting, mapping, ground and airborne EM and magnetometer surveying was carried out. Reportedly, six EM anomalies were tested by diamond drilling and one of these drillholes intersected 0.45 m of massive pyrite. Due to a lack of understanding of the geological environment and geophysical character of other known deposits no significant mineralization was detected and the claims were allowed to lapse.
Restaked as Sue cl 1-1070 (80651) in Aug/74 by a syndicate of Conwest companies (Chimo Gold Mines Ltd, Consolidated Canadian Farday Ltd and International Mogul Mines Ltd) and Teck Corporation Ltd. U.S. Steel Western Hemisphere Inc acquired the Teck interest early in 1975 and formed the Macmillan Joint Venture. The joint venture carried out extensive bulldozer gridding, linecutting, EM, magnetometer and gravity surveying and geological mapping in 1975; additional gravity surveying in 1976 and 1977; drilled 17 holes (2,531 m) in 1978; MaxMin EM surveying, airstrip construction and drilling of 10 holes (2,481 m) in 1979.
Welcome North Mines Ltd tied on RSVP, PVA and Pelly cl (YA25299) in Aug/79 and optioned the claims to E and B Exploration Inc (Pelly Project), which carried out airborne magnetometer and EM surveying and geochemical sampling in 1980.
The Conwest syndicate's interest was acquired by Getty Canadian Metals Ltd in the spring of 1980 which staked various Get A, Get B, Get C and Get D claims (YA49085) in Jun/80 and carried out geological mapping, soil geochemical sampling, MaxMin EM and gravity surveying in 1980; EM and magnetometer surveying, soil and lake bottom geochemical sampling, prospecting and drilling of 3 holes (709.3 m) in 1981; linecutting, geochemical sampling, EM and gravity surveying and drilling of 3 holes (943.7 m) in 1982; linecutting, drilling of 69 overburden holes (531 m) and 2 diamond drill holes (2,045.5 m) in 1983; and diamond drilling of one hole (457.2 m) in 1984.
Most of the Sue claims surrounding the showing were subsequently abandoned and were restaked as Clear cl 1-490 (YB25815) in Jun/89 by Total Energold Corporation, which also purchased Conwest's NPI interest. Total Energold staked Clear cl 491-598 (YB27222) in April and May/90 and carried out geochemical soil and rock sampling and geological mapping to evaluated 18 target areas later in the year. The geochemical sampling included hand-augered soil samples and 35 samples of glacial overburden collected down-ice from the deposit using an overburden drill. The property was optioned to Mitsui Kinzoku Resources of Canada Inc, a wholly owned subsidiary of Mitsui Mining and Smelting Company Ltd in 1991. At the same time Total Energold purchased U.S. Steel's interest in the property.
Work carried out in 1991 consisted of diamond drilling of 19 holes (4,588.2 m), geological mapping, IP and gravity surveying, geochemical sampling, linecutting and trenching and staking of Clear cl 599-674 (YB36109) in Jul/91. In 1992 Total Erickson Resources Ltd, a wholly owned subsidiary of Total Energold carried out diamond drilling of 10 holes (3,100.1 m), geological mapping, soil geochemical sampling, trenching, linecutting and IP, gravity and Power Line magnetotelluric surveying.
The Clear and Sue claims were transferred to Energold Minerals Inc in Nov/92. In 1993, Mitsui and Energold carried out gravity and magnetometer surveying, auger assisted soil sampling, rock chip sampling, geological mapping and drilling of 6 holes (1,364 m). Baseline environmental studies were also carried out before Mitsui dropped its option. Energold Mining Ltd changed its name to Energold Drilling Corporation in Sep/2005.
2005-2010 not summarized yet.
A resource estimate was prepared by SRK Consulting for Copper Ridge Explorations Inc in February 2010.
Capsule Geology
The Clear Lake deposit is a proximal exhalative massive pyritic sulphide body within which drilling has outlined approximately 30 million tonnes of massive sulphides (mostly pyrite), including a geological reserve of 5,570,114 million tonnes grading 11.4% Zn, 2% Pb and 38.01 g/t Ag. The deposit is hosted by carbonaceous argillite, siltstone, chert and tuff of the Devonian to Mississippian Earn Group.
The property is bisected by the Tintina Fault. North of the fault are phyllite of the Lower Cambrian Mt Mye Formation and calcareous phyllite and limestone of the Cambrian to Ordovician Vangorda Formation. South of the fault are Ordovician to Lower Devonian Road River Group shale, and the Devonian to Mississippian Earn Group clastic rocks which host the Clear Lake deposit. Glacial overburden 5 to 26 m thick covers the property, and the geology is known mainly from drillholes and interpretations of geophysical surveys.
The main sulphide body was discovered in 1978 while drilling a 3 mgal residual gravity anomaly. The gravity anomaly coincides with magnetic and EM anomalies and is situated beside a small acidic lake containing geochemically anomalous lake bottom sediments. Lake bottom samples assayed up to 19,000 ppm Zn, 1.2 ppm Ag, and 20 to 40 ppm Cu. A subtle gossan was later recognized over the target.
The deposit is sigmoidal in shape, approximately 1 000 m long and up to 120 m wide, and pinches at depth. It dips steeply to the east, and Bouma sequences in drill core indicate that it is overturned. Sulphide minerals are laminated and consist largely of framboidal pyrite which is slumped and fragmented in places. The best drill intersection assayed 18.3% Zn, 2.15% Pb and 58.6 g/t Ag across 13 m. Tuffaceous rocks intercalated with the sulphides reach a thickness of 30 m in the original footwall, stratigraphically beneath the main massive sulphide lens. The tuff exhibits relict pyroclastic texture, with both matrix and fragments largely altered to soft grey clay, and local concretions of galena, sphalerite, barite, siderite and calcite.
Argillite which lies stratigraphically beneath the overturned footwall tuff is silicified to a depth of 90 m below the deposit. The overturned hanging wall is formed by a layer of argillite which is silicified so extensively it resembles mottled to laminated chert. Irregular pyrite stringers and masses are common throughout both the hanging wall and footwall argillite. Massive barite in several drillholes appears to be peripheral to the deposit and forms a partial cap over it. Barite and tuff lenses intersected at depth in the 1991 drillholes indicate that there is potential for another sulphide lens below the main orebody.
A trace element study of the tuffaceous rocks by Jim Morin of DIAND revealed high Ti and P contents and high K2O/Na2O ratios, consistent with an alkaline volcanic environment. The mineral deposit is inferred to be an exhalative deposit related to Devonian rifting. Worm tubes replaced by quartz and calcite surrounded and partly replaced by sphalerite and pyrite have been found in drill core, and the sulphides are believed to have precipitated from a hydrothermal fluid hotter than 350°C which mixed with cold seawater at a black smoker vent.
Soil sampling using hand augers and an overburden drill in 1990 located anomalies in several new areas. North of the Tintina Fault, stratiform galena and sphalerite outcrop at the transition between Mt Mye and the Vangorda Formation rocks, the same stratigraphic interval as the Faro deposits. Specimens from this area assayed up to 2.68% Zn, 0.78% Pb and 13.7 g/t Ag.
Drilling in 1992 showed that some gravity anomalies are due to bedrock highs adjacent to conductive graphitic shear zones which trend east-west through the main deposit. No new massive sulphide lenses were discovered.
A resource estimate was prepared by SRK consulting for Copper Ridge Explorations in February 2010. SRK estimates that the Clear Lake deposit contains 7.765 million tonnes of Inferred Mineral resource grading 1.08% Pb, 7.6% Zn and 22 g/t Ag at a 4% (Pb+Zn) cut-off, with Pb grades capped to 1.5% and Ag grades capped at 60 g/t.
Location Map
Last Updated: Aug 21, 2018
Work History
| Year | Work Type | Comment |
|---|---|---|
| 2011 | Studies: Resource Estimate | KRK Consulting, 2010, for Copper Ridge Explorations Inc. |
| 1993 | Drilling: Diamond | Six holes, 1,364 m. |
| 1993 | Geochemistry: Soil | Also rock sampling. |
| 1993 | Geology: Bedrock Mapping | |
| 1993 | Ground Geophysics: Gravity Survey | Also magnetic survey. |
| 1992 | Drilling: Diamond | Ten holes, 3,100.1 m. |
| 1992 | Geochemistry: Soil | |
| 1992 | Geology: Bedrock Mapping | |
| 1992 | Ground Geophysics: IP | Also gravity. |
| 1992 | Trenching | |
| 1991 | Drilling: Diamond | Nineteen holes, 4,588.2 m. |
| 1991 | Geology: Bedrock Mapping | |
| 1991 | Ground Geophysics: IP | Also gravity survey. |
| 1991 | Trenching | |
| 1990 | Geochemistry: Soil | Also rock sampling. |
| 1990 | Geology: Bedrock Mapping | |
| 1984 | Drilling: Diamond | One hole, 457.2 m. |
| 1983 | Drilling: Diamond | Two holes, 2,045.5 m. |
| 1983 | Drilling: Percussion | |
| 1982 | Drilling: Diamond | Three holes, 943.7 m. |
| 1982 | Geochemistry: Soil | |
| 1982 | Ground Geophysics: EM | Also gravity survey. |
| 1981 | Drilling: Diamond | Three holes, 709.3 m. |
| 1981 | Geochemistry: Soil | Also silt sampling. |
| 1981 | Ground Geophysics: EM | Also magnetic survey. |
| 1980 | Geochemistry: Soil | |
| 1980 | Geology: Bedrock Mapping | |
| 1980 | Ground Geophysics: EM | Also gravity survey. |
| 1979 | Development, Surface: Air Strip | |
| 1979 | Drilling: Diamond | Ten holes, 2,481 m. |
| 1979 | Ground Geophysics: Downhole Survey | Also magnetometer survey. |
| 1978 | Drilling: Diamond | Seventeen holes, 2,531 m. |
| 1977 | Ground Geophysics: Gravity Survey | |
| 1976 | Ground Geophysics: Gravity Survey | |
| 1975 | Geochemistry: Silt | |
| 1975 | Ground Geophysics: EM | Also magnetic and gravity surveys. |
| 1975 | Geology: Bedrock Mapping | |
| 1966 | Airborne Geophysics: Electromagnetic | Also magnetic survey. |
| 1966 | Geology: Bedrock Mapping | |
| 1966 | Other: Prospecting |
Regional Geology - Terrane
Group: Ancestral North America
Affinity: W Laurentia
Name: Cassiar
Realm: Laurentia
Regional Geology - Bedrock
Supergroup:
Group/Suite: Earn
Formation:
Member:
Terrane: Cassiar
Period Max: Devonian
Age Max: 385 MA
Period Min: Carboniferous
Age Min: 345 MA
Rock Major: slate/sandstone/conglomerate
Rock Minor: barite/limestone
Reference: Colpron et al. (2002) - YGS OF 2002-9; GSC OF 1457
Geological Unit (1M): DMEC
Geological Unit (250K): DMEC1
Assessment Reports that overlap occurrence
| Report Number | Year | Title | Worktypes | Holes Drilled | Meters Drilled |
|---|---|---|---|---|---|
| 097206 | 2018 | Assessment Report on 2018 Surface Work on the Clear Lake Property | Rock - Geochemistry | ||
| 095140 | 2009 | 2009 Ground Geophysical Program Clear Lake Project | Gravity Survey - Ground Geophysics, IP - Ground Geophysics | ||
| 095047 | 2008 | 2008 Airborne Geophysical Program Clear Lake Project | VTEM - Airborne Geophysics | ||
| 093145 | 1993 | 1993 Geological, Physical, Geophysical, Geochemical and Diamond Drilling Assessment Report on the Clear Lake Property | Diamond - Drilling, Drill Core - Geochemistry, Rock - Geochemistry, Silt - Geochemistry, Soil - Geochemistry, Regional Bedrock Mapping - Geology, Gravity Survey - Ground Geophysics, Magnetics - Ground Geophysics, Line Cutting - Other | 6 | 1364 |
| 093060 | 1992 | Geological, Physical, Geophysical, Geochemical and Diamond Drilling Assessment Report on the Clear Lake Property | Diamond - Drilling, Soil - Geochemistry, Regional Surficial Mapping - Geology, Gravity Survey - Ground Geophysics, IP - Ground Geophysics, Resistivity - Ground Geophysics, Line Cutting - Other, Environmental Assessment/Impact - Studies, Mechanical - Trenching | 10 | 3100 |
| 093013 | 1991 | Geological, Physical, Geophysical, Geochemical and Diamond Drilling Assessment Report on the Clear Lake Property | Diamond - Drilling, Rock - Geochemistry, Silt - Geochemistry, Soil - Geochemistry, Regional Bedrock Mapping - Geology, Regional Surficial Mapping - Geology, Gravity Survey - Ground Geophysics, IP - Ground Geophysics, Line Cutting - Other, Prospecting - Other, Mechanical - Trenching | 19 | 4588.20 |
| 092871 | 1990 | Geochemical and Geological Assessment Report on the Clear Lake Property | Auger - Drilling, Rock - Geochemistry, Soil - Geochemistry, Regional Bedrock Mapping - Geology | ||
| 092895 | 1990 | Geochemical and Geological Assessment Report on the Clear Lake Property | Auger - Drilling, Portable - Drilling, Rock - Geochemistry, Soil - Geochemistry, Regional Bedrock Mapping - Geology | ||
| 090932 | 1981 | Macmillan Joint Venture, Clear Lake Area, Yukon / by C. W. Payne | Diamond - Drilling | 3 | 478.80 |
| 091036 | 1981 | Macmillan Joint Venture Assessment Report - Aerial Photography, Orthophoto and Line Maps Report | Orthophoto - Airphotography | ||
| 090659 | 1980 | Macmillan Joint Venture Geophysical Surveys March to May, 1980 Sue Claims Whitehorse Mining District | EM - Ground Geophysics, Gravity Survey - Ground Geophysics | ||
| 090478 | 1979 | Macmillan Joint Venture Geophysical Surveys March - April 1979 | EM - Ground Geophysics, Magnetics - Ground Geophysics | ||
| 091269 | 1979 | [Diamond drill hole logs] / Getty Canadian Metals Ltd. on the Clear Lake Property | Diamond - Drilling, Drill Core - Geochemistry, Line Cutting - Other | 4 | 1545 |
| 090011 | 1975 | Macmillan Joint Venture Progress Report Number 1 Geophysical Surveys February - May 1975 | Winter Road - Development, Surface, EM - Ground Geophysics, Gravity Survey - Ground Geophysics, Magnetics - Ground Geophysics, Line Cutting - Other, Photogrammetry - Remote Sensing, Mechanical - Trenching |
Related References
| Number | Title | Page(s) | Document Type |
|---|---|---|---|
| ARMC020070 | Annual report 1989 - Total Energold Corporation | Report | |
| ARMC020099 | Project summary and business proposal - MacMillan joint venture/Clear Lake project | Report | |
| ARMC020100 | Property summary - Total Energold Corporation - Clear Lake property - May 1990 | Report | |
| ARMC020101 | Memo to C.H. Frame Re: Clear Lake/Yukon Territory with location map | Miscellaneous Company Documents | |
| ARMC020102 | Memo to M.H. Pelley Re: Clear Lake | Miscellaneous Company Documents | |
| ARMC020103 | Memo to M.H. Pelley Re: Clear Lake lead zinc property, Yukon | Miscellaneous Company Documents |
| Citations |
|---|
| Grapes, K.J., 1987. Lithologic and Textural study of the Clear Lake Fe-Zn-Pb-Ag massive sulphide deposit, Yukon Territory, Canada. MSc Thesis, Carleton University, Ottawa. |
| SRK Consulting, 2010, Clear Lake Zinc-Lead-Silver Deposit, Yukon, prepared for Copper Ridge Explorations Inc. |
Drill Core at YGS Core Library
| Number | Property | Year Drilled | Core Size | Photos | Data |
|---|---|---|---|---|---|
| 91-50 | Clear Lake | 1991 | NQ | 12 | 1 |
| 91-51 | Clear Lake | 1991 | NQ | 2 | 1 |
| 91-52 | Clear Lake | 1991 | NQ | 8 | 1 |
| 91-54 | Clear Lake | 1991 | NQ | 6 | 1 |
