General Information
Secondary Commodities: copper, gold, silver
Deposit Type(s): Porphyry Subvolcanic Cu-Au-Ag (As-Sb)
Location(s): 63.549720 N, -131.518610 W
NTS Mapsheet(s): 105O12
Location Comments: 1.5 Kilometres
Hand Samples Available at YGS: No
Capsule
Work History
Staked as Christina cl 1-7 (YB03811) in August, 1990, by S. Ebert and G. Couture, who performed geological mapping, silt and rock geochemistry and petrographic work in the same year.
Restaked as Rog cl 1-14 (YB65316) by Eagle Plains Resources Ltd and Miner River Resources Ltd in May/96. The companies carried out a reconnaissance mapping and rock sampling program later in the year.
Capsule Geology
The area is located in the north-central portion of the Selwyn Basin, near the boundary with the Mackenzie Platform. The area is underlain by Paleozoic sedimentary rocks which have been intruded by mid-Cretaceous granitic intrusions.
The occurrence is situated 14 km west of Emerald Lake and covers a porphyry copper-gold target. A 900 x 400 m area containing disseminated sulphides and arsenopyrite-tourmaline-quartz veins occurs along the south flank of a mid-Cretaceous granite stock assigned to the Tombstone suite, which intrudes Devonian to Mississippian slate, argillite and chert assigned to the Earn Assemblage. Petrographic studies show that the host intrusion is hydrothermally altered. A stockwork zone of secondary orthoclase and biotite forms a potassic alteration halo around the south margin of the intrusion, and is overprinted by sericite replacing plagioclase and chlorite replacing biotite. The alteration zones appear to be centred on a magnetic high.
Mineralized veins ranging in size from about 2 mm to 37.5 cm wide (average about 3 cm), occur along joints
and form up to 10% of the rock. The veins are zoned, with quartz on the outside and tourmaline and arsenopyrite in the centre. Chalcopyrite, pyrite, malachite and azurite also occur in the veins and as disseminations in the intrusion. Most of the veins return anomalous copper values ranging from 231 ppm Cu to 5.31% Cu, while gold values range from 0.02 to 14 g/t Au. Silver values range from 1.3 g/t to 79.5 g/t Ag and arsenic values are almost all anomalous. A few specimens also returned anomalous values for Bi, Ba and Mo. A specimen of unveined granite assayed 202 ppm Cu, 0.52 g/t Au and 3.7 g/t Ag.
Five hundred metres south of the intrusive contact, brecciated siltstone with a matrix of tourmaline and arsenopyrite is cut by mineralized quartz veins containing up to 25% arsenopyrite and variable amounts of pyrrhotite, pyrite and chalcopyrite. Assays of the breccia averaged 2 g/t Au, with up to 1% Cu and 31 g/t Ag. Late stage aplite dykes cut both the mid-Cretaceous intrusion and the sedimentary rocks. All of the streams draining the east side of the intrusion returned anomalous copper values, with a few also returning anomalous Au, Ag, Pb, Zn and Mo values.
Eagle Plains and Miner River Resources¿ exploration program was designed to verify results obtained by Ebert in 1990. A 1.5 m chip sample collected across the breccia zone returned of 4.6 g/t Au and 111 ppm Bi. A 1.5 m chip sample collected from a 25 cm wide quartz-arsenopyrite vein containing 10% arsenopyrite returned 1.8 g/t Au and 827 ppm Cu.
References
S. EBERT, Feb/91. Assessment Report #092956 by S. Ebert.
EAGLE PLAINS RESOURCES LTD AND MINER RIVER RESOURCES LTD, May/97. Assessment Report #093614 by J.R. Dickie.
GORDEY, S.P., AND MAKEPEACE, A.J., 1999. Yukon digital geology, S.P. Gordey and A.J. Makepeace (comp.); Geological Survey of Canada, Open File D3826, and Exploration and Geological Services Division, Yukon, Indian and Northern Affairs Canada, Open File 1999-1 (D)
Staked as Christina cl 1-7 (YB03811) in August, 1990, by S. Ebert and G. Couture, who performed geological mapping, silt and rock geochemistry and petrographic work in the same year.
Restaked as Rog cl 1-14 (YB65316) by Eagle Plains Resources Ltd and Miner River Resources Ltd in May/96. The companies carried out a reconnaissance mapping and rock sampling program later in the year.
Capsule Geology
The area is located in the north-central portion of the Selwyn Basin, near the boundary with the Mackenzie Platform. The area is underlain by Paleozoic sedimentary rocks which have been intruded by mid-Cretaceous granitic intrusions.
The occurrence is situated 14 km west of Emerald Lake and covers a porphyry copper-gold target. A 900 x 400 m area containing disseminated sulphides and arsenopyrite-tourmaline-quartz veins occurs along the south flank of a mid-Cretaceous granite stock assigned to the Tombstone suite, which intrudes Devonian to Mississippian slate, argillite and chert assigned to the Earn Assemblage. Petrographic studies show that the host intrusion is hydrothermally altered. A stockwork zone of secondary orthoclase and biotite forms a potassic alteration halo around the south margin of the intrusion, and is overprinted by sericite replacing plagioclase and chlorite replacing biotite. The alteration zones appear to be centred on a magnetic high.
Mineralized veins ranging in size from about 2 mm to 37.5 cm wide (average about 3 cm), occur along joints
and form up to 10% of the rock. The veins are zoned, with quartz on the outside and tourmaline and arsenopyrite in the centre. Chalcopyrite, pyrite, malachite and azurite also occur in the veins and as disseminations in the intrusion. Most of the veins return anomalous copper values ranging from 231 ppm Cu to 5.31% Cu, while gold values range from 0.02 to 14 g/t Au. Silver values range from 1.3 g/t to 79.5 g/t Ag and arsenic values are almost all anomalous. A few specimens also returned anomalous values for Bi, Ba and Mo. A specimen of unveined granite assayed 202 ppm Cu, 0.52 g/t Au and 3.7 g/t Ag.
Five hundred metres south of the intrusive contact, brecciated siltstone with a matrix of tourmaline and arsenopyrite is cut by mineralized quartz veins containing up to 25% arsenopyrite and variable amounts of pyrrhotite, pyrite and chalcopyrite. Assays of the breccia averaged 2 g/t Au, with up to 1% Cu and 31 g/t Ag. Late stage aplite dykes cut both the mid-Cretaceous intrusion and the sedimentary rocks. All of the streams draining the east side of the intrusion returned anomalous copper values, with a few also returning anomalous Au, Ag, Pb, Zn and Mo values.
Eagle Plains and Miner River Resources¿ exploration program was designed to verify results obtained by Ebert in 1990. A 1.5 m chip sample collected across the breccia zone returned of 4.6 g/t Au and 111 ppm Bi. A 1.5 m chip sample collected from a 25 cm wide quartz-arsenopyrite vein containing 10% arsenopyrite returned 1.8 g/t Au and 827 ppm Cu.
References
S. EBERT, Feb/91. Assessment Report #092956 by S. Ebert.
EAGLE PLAINS RESOURCES LTD AND MINER RIVER RESOURCES LTD, May/97. Assessment Report #093614 by J.R. Dickie.
GORDEY, S.P., AND MAKEPEACE, A.J., 1999. Yukon digital geology, S.P. Gordey and A.J. Makepeace (comp.); Geological Survey of Canada, Open File D3826, and Exploration and Geological Services Division, Yukon, Indian and Northern Affairs Canada, Open File 1999-1 (D)
Location Map
Last Updated: Sep 15, 2011
Work History
| Year | Work Type | Comment |
|---|---|---|
| 1996 | Geology: Bedrock Mapping | Program was reconnaissance in nature. |
| 1996 | Other | Program was reconnaissance in nature. |
| 1990 | Geochemistry: Rock | Also performed petrographic work. |
| 1990 | Geochemistry: Silt | |
| 1990 | Geology: Bedrock Mapping |
Regional Geology - Terrane
Group: Ancestral North America
Affinity: W Laurentia
Name: North America - basinal strata
Realm: Laurentia
Regional Geology - Bedrock
Supergroup:
Group/Suite: Earn
Formation: Portrait Lk/Prevost/L Devonian beds?
Member:
Terrane: Laurentia
Period Max: Devonian
Age Max: 410 MA
Period Min: Devonian
Age Min: 359 MA
Rock Major: chert/shale/argillite
Rock Minor: barite/limestone
Reference: Cecile & Abbott (1989) - GSC OF 2076
Geological Unit (1M): DME
Geological Unit (250K): DME2
Assessment Reports that overlap occurrence
| Report Number | Year | Title | Worktypes | Holes Drilled | Meters Drilled |
|---|---|---|---|---|---|
| 096026 | 2011 | Assessment Report, 2011 Surface Geochemical Exploration Program | Rock - Geochemistry, Silt - Geochemistry, Soil - Geochemistry | ||
| 093827 | 1997 | 1997 Geological Assessment Report on Emerald Lake Claims | Rock - Geochemistry, Silt - Geochemistry, Soil - Geochemistry | ||
| 093614 | 1996 | Geological Assessment Report for the Rog 1-14 and Fan 1-10 Mineral Claims | Rock - Geochemistry, Detailed Bedrock Mapping - Geology | ||
| 092956 | 1991 | Assessment Report Geological Descriptions of the Christina and Scronk Claims | Rock - Geochemistry, Silt - Geochemistry, Petrographic - Lab Work/Physical Studies | ||
| 091076 | 1982 | The Geology of the Old Cabin Claims | Detailed Bedrock Mapping - Geology, Process/Interpret - Pre-existing Data | ||
| 019809 | 1968 | Hess Area Project Proposed Property Follow-Up 1968 Field Season | Research/Summarize - Pre-existing Data | ||
| 019033 | 1968 | Atlas Explorations Limited Project Report 1968 Hess River Area | Silt - Geochemistry, Soil - Geochemistry, Regional Bedrock Mapping - Geology | ||
| 018947 | 1967 | Hess River Project Report | Rock - Geochemistry, Soil - Geochemistry, Detailed Bedrock Mapping - Geology | ||
| 019032 | 1967 | Hess River Project Report | Data Compilation - Pre-existing Data |
Related References
| Number | Title | Page(s) | Document Type |
|---|---|---|---|
| ARMC016470 | Aeromagnetic series map of 105O/12 showing geology | Geochemical Map |
| Citations |
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