General Information
Secondary Commodities: coal
Deposit Type(s): Coal
Location(s): 61.262220 N, -139.120830 W
NTS Mapsheet(s): 115G06
Location Comments: .5 Kilometres
Hand Samples Available at YGS: No
Capsule
Work History
Coal was found in this area about 1952 by the GSC and was mapped and trenched in 1970-71 by N.H. Ursel & Assoc. L. while evaluating Coal Exploration Licences 14 and 18.
Capsule Geology
The occurrence is located in Wrangellia, an accreted terrane extending 2340 km from Alaska to southern B.C.. In the area of the occurrence, Wrangellia is bounded to the northeast by the Denali Fault System and to the southwest by the Duke River Fault. The oldest Wrangellian rocks in the region are the Pennsylvanian to Permian Skolai Group volcanic and sedimentary rocks. The Skolai Group is stratigraphically overlain by Middle(?) Triassic phyllite, Upper Triassic Nikolai formation basalt and Upper Triassic McCarthy Formation Limestone and phyllite. Tertiary volcanic and sedimentary rocks unconformably overlie the sequence.
Two major suites of intrusive rocks are present in the belt. The oldest is Triassic and includes gabbro, peridotite, dunite and clinopyroxenite of the Kluane mafic-ultramafic complex and gabbro sills and dykes of the Maple Creek Gabbro. The Maple Creek gabbro is though to be coeval with the Kluane mafic-ultramafic complex and to have acted as a feeder to the Nikolai formation. The Cretaceous Kluane Ranges suite are dioritic to granodioritic in composition and occur throughout northern Wrangellia. Minor Tertiary sills, dykes and stocks of felsic to intermediate composition are also present.
The occurrence lies within the Eocene-Oligocene Amphitheatre Formation, a package of terrestrial sediments and coal deposited in structurally controlled basins related to the Denali fault system. Coal seams have been located in three separate areas within the Amphitheatre Formation. The northwestern location, which is the one originally described by the GSC, consists of two seams 0.9 and 1.8 m thick separated by 4 m of shale. Float occurrences suggest that as many as four seams may be present. Sampling in 1970 indicated that both seams are Sub-Bituminous C and non-coking.
A similar section consisting of 3 seams aggregating 4.0 m of coal in a 15 m interval was measured 4 km to the south at approximately the same stratigraphic level. Another 4.3 m seam with claystone interbeds that occurs about 238 m lower in the section is separated by a 1 m thick porphyritic sill and the coal has been altered to natural coke on either side. Sampling in 1970 indicated it to be Sub-Bituminous A and non-coking.
The third area, situated about 3.2 km southeast of the first, was discovered in 1971. It consists of two seams 2.0 m and 0.8 m thick located about 600 m apart at approximately the same stratigraphic level. All the coal seams in the district contain pale yellow lump resin that may be suitable for the manufacture of printing ink.
References
AURUM GEOLOGICAL CONSULTANTS INC., 1994. Yukon Coal Inventory 1994. Energy and Mines Branch, Economic Development, Yukon Territorial Government, 169 p.
DODDS, C.J., AND CAMPBELL, R.B., 1992. Overview, legend and mineral deposit tabulations for Geological Survey of Canada Open Files 2188, 2189, 2190 and 2191.
GORDEY, S.P. AND MAKEPEACE, A.J., 2003. Yukon Digital Geology, version 2.0, S.P. Gordey and A.J. Makepeace (comp); Geological Survey of Canada, Open File 1749 and Yukon Geological Survey, Open File 2003-9 (D).
ISRAEL, S. and VAN ZEYL, D., 2004. Preliminary bedrock geology of the Quill Creek area (parts of NTS 115G/5, 6, 12), southwest Yukon (1:50 000 scale). Yukon Geological Survey, Open File 2004-2.
ISRAEL, S., TIZZARD, A. and MAJOR, J., 2005. Geological map of the Duke River area (parts of NTS 115G/2, 3, 5, 6, 7), Yukon (1:50,000 scale). Yukon Geological Survey, Open File 2005-11.
MINERAL INDUSTRY REPORT 1969-70, p. 153-154.
N.H. URSEL AND ASSOCIATES LTD, Oct/70. Assessment Report *#060989 by E.L. Speelman.
N.H. URSEL AND ASSOCIATES LTD, 1971. Assessment Report *#019866 by E.L. Speelman.
N.H. URSEL AND ASSOCIATES LTD, 1971. Assessment Report #060988 by E.L. Speelman.
READ, P.B. and MONGER, J.W.H., 1976. Pre-Cenozoic assemblages of the Kluane and Alsek Ranges, southwest Yukon Territory. Geological Survey of Canada, Open File 381, 96 p.
Coal was found in this area about 1952 by the GSC and was mapped and trenched in 1970-71 by N.H. Ursel & Assoc. L. while evaluating Coal Exploration Licences 14 and 18.
Capsule Geology
The occurrence is located in Wrangellia, an accreted terrane extending 2340 km from Alaska to southern B.C.. In the area of the occurrence, Wrangellia is bounded to the northeast by the Denali Fault System and to the southwest by the Duke River Fault. The oldest Wrangellian rocks in the region are the Pennsylvanian to Permian Skolai Group volcanic and sedimentary rocks. The Skolai Group is stratigraphically overlain by Middle(?) Triassic phyllite, Upper Triassic Nikolai formation basalt and Upper Triassic McCarthy Formation Limestone and phyllite. Tertiary volcanic and sedimentary rocks unconformably overlie the sequence.
Two major suites of intrusive rocks are present in the belt. The oldest is Triassic and includes gabbro, peridotite, dunite and clinopyroxenite of the Kluane mafic-ultramafic complex and gabbro sills and dykes of the Maple Creek Gabbro. The Maple Creek gabbro is though to be coeval with the Kluane mafic-ultramafic complex and to have acted as a feeder to the Nikolai formation. The Cretaceous Kluane Ranges suite are dioritic to granodioritic in composition and occur throughout northern Wrangellia. Minor Tertiary sills, dykes and stocks of felsic to intermediate composition are also present.
The occurrence lies within the Eocene-Oligocene Amphitheatre Formation, a package of terrestrial sediments and coal deposited in structurally controlled basins related to the Denali fault system. Coal seams have been located in three separate areas within the Amphitheatre Formation. The northwestern location, which is the one originally described by the GSC, consists of two seams 0.9 and 1.8 m thick separated by 4 m of shale. Float occurrences suggest that as many as four seams may be present. Sampling in 1970 indicated that both seams are Sub-Bituminous C and non-coking.
A similar section consisting of 3 seams aggregating 4.0 m of coal in a 15 m interval was measured 4 km to the south at approximately the same stratigraphic level. Another 4.3 m seam with claystone interbeds that occurs about 238 m lower in the section is separated by a 1 m thick porphyritic sill and the coal has been altered to natural coke on either side. Sampling in 1970 indicated it to be Sub-Bituminous A and non-coking.
The third area, situated about 3.2 km southeast of the first, was discovered in 1971. It consists of two seams 2.0 m and 0.8 m thick located about 600 m apart at approximately the same stratigraphic level. All the coal seams in the district contain pale yellow lump resin that may be suitable for the manufacture of printing ink.
References
AURUM GEOLOGICAL CONSULTANTS INC., 1994. Yukon Coal Inventory 1994. Energy and Mines Branch, Economic Development, Yukon Territorial Government, 169 p.
DODDS, C.J., AND CAMPBELL, R.B., 1992. Overview, legend and mineral deposit tabulations for Geological Survey of Canada Open Files 2188, 2189, 2190 and 2191.
GORDEY, S.P. AND MAKEPEACE, A.J., 2003. Yukon Digital Geology, version 2.0, S.P. Gordey and A.J. Makepeace (comp); Geological Survey of Canada, Open File 1749 and Yukon Geological Survey, Open File 2003-9 (D).
ISRAEL, S. and VAN ZEYL, D., 2004. Preliminary bedrock geology of the Quill Creek area (parts of NTS 115G/5, 6, 12), southwest Yukon (1:50 000 scale). Yukon Geological Survey, Open File 2004-2.
ISRAEL, S., TIZZARD, A. and MAJOR, J., 2005. Geological map of the Duke River area (parts of NTS 115G/2, 3, 5, 6, 7), Yukon (1:50,000 scale). Yukon Geological Survey, Open File 2005-11.
MINERAL INDUSTRY REPORT 1969-70, p. 153-154.
N.H. URSEL AND ASSOCIATES LTD, Oct/70. Assessment Report *#060989 by E.L. Speelman.
N.H. URSEL AND ASSOCIATES LTD, 1971. Assessment Report *#019866 by E.L. Speelman.
N.H. URSEL AND ASSOCIATES LTD, 1971. Assessment Report #060988 by E.L. Speelman.
READ, P.B. and MONGER, J.W.H., 1976. Pre-Cenozoic assemblages of the Kluane and Alsek Ranges, southwest Yukon Territory. Geological Survey of Canada, Open File 381, 96 p.
Location Map
Last Updated: Sep 15, 2011
Work History
| Year | Work Type | Comment |
|---|---|---|
| 1970 | Geology: Bedrock Mapping | |
| 1970 | Trenching | |
| 1952 | Geology: Bedrock Mapping | Originally found by Geological Survey of Canada. |
Regional Geology - Terrane
Group: Insular
Affinity: NE Panthalassa
Name: Wrangellia
Realm: Panthalassa
Regional Geology - Bedrock
Supergroup:
Group/Suite:
Formation: Amphitheatre
Member:
Terrane:
Period Max: Paleogene
Age Max: 33 MA
Period Min: Paleogene
Age Min: 23 MA
Rock Major: conglomerate/sandstone/mudstone
Rock Minor:
Reference: Israel et al. (2005) - YGS OF 2005-11
Geological Unit (1M): OA
Geological Unit (250K): OA
Assessment Reports that overlap occurrence
| Report Number | Year | Title | Worktypes | Holes Drilled | Meters Drilled |
|---|---|---|---|---|---|
| 060988 | 1971 | Report on Niamodlaoc Mountain Coal Prospect | Rock - Geochemistry, Silt - Geochemistry, Prospecting - Other | ||
| 019866 | 1971 | [Report on Reconnaissance of Burwash Creek and Niamodlaoc Mountain Coal Prospect] | Prospecting - Other | ||
| 060989 | 1970 | Report on Niamodlaoc Mountain Coal Prospect, 1970 Field Season | Rock - Geochemistry |
