Ontario Geological Survey
Permanent Link to this Record:
MDI53H13SW00006
| Record Name(s) | Ernie Island - 1971 |
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| Related Record Type | |
| Related Record(s) | |
| Record Status | Occurrence |
| Date Created | 1985-Aug-20 |
| Date Last Modified | 2022-Mar-02 |
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| Revised By |
Primary Commodities: Copper
Township or Area: Post Island Area, Beardy Creek Area
Latitude: 53° 45' 2.44" Longitude: -89° 47' 34.3"
UTM Zone: 16 Easting: 315859 Northing: 5959403 UTM Datum: NAD83
Resident Geologist District: Thunder Bay North
NTS Grid: 53H13SW
Point Location Description: Precise
Location Method: Conversion from MDI
1912: Reconnaissance scale mapping by J.B. Tyrrell of the Geological Survey of Canada. 1964: Ontario Department of Mines reconnaissance scale mapping by P.P. Hudec. 1971: Ontario Geological Survey completed more detailed mapping by Thurston. OGS grab sample from vein on a small island off NW corner of Ernie Island: 1.05% Cu. As of 2009, this area has been alienated by the province and is not open for staking. No assessment files were found on record.
Province: Superior
Subprovince: Sachigo
Terrane: North Caribou
Geological Age: Archean
| Rock Type | Rank | Composition | Texture | Relationship | Mafic lava flow-unsubdivided | 1 | Basalt To Andesite |
|---|---|---|---|---|
| Vein | 2 | Quartz | Host |
| Rank | Mineral Name | Class | Economic Mineral Type | Alteration Mineral Type | Alteration Ranking | Alteration Intensity | Alteration Style |
|---|---|---|---|---|---|---|---|
| 1 | Chalcopyrite | Economic | Ore | ||||
| 2 | Pyrite | Economic | Ore | ||||
| 3 | Pyrrhotite | Economic | Ore |
Aug 16, 2018 (Therese Pettigrew) - On a small island off the northwest corner of Ernie Island a 30 cm wide quartz vein located along the contact between pillowed mafic metavolcanics to the south and massive metavolcanics to the north carried chalcopyrite and pyrite mineralization. A grab sample of the vein material taken OGS staff returned 1.05 percent copper upon analysis by the Geoscience Laboratories. On the southwest tip of Ernie Island a shear zone 30 m wide cuts massive to pillowed mafic metavolcanics. The shear zone trends S85E, dips vertically, and contains numerous quartz veins and stringers 2 to 5 cm in width parallel to the schistosity. These veins contain up to 5 percent pyrite. Samples of the vein material taken by OGS staff for assay returned negligible values. For a distance up to 1.5 km east from the southwest tip of Ernie Island minor chalcopyrite, pyrite, and pyrrhotite occur as disseminated grains and in association with quartz veins. The greatest concentration of mineralization is 20 to 30 m north of the contact between a flow top breccia (9 m thick) and an overlying massive flow. The metavolcanics strike east to S85E, roughly parallel to the shoreline, and dip vertically. The copper showing reported by Hudec (1964, Map 2045) on the south shore of Ernie Island was relocated by this field party. The showing consists of a 43 cm wide quartz vein occupying the centre of a 18 m wide shear zone. The intensity of shearing decreases in both directions away from the vein. The vein is exposed for a length of 3.5 m and was observed to continue out under the waters of Big Trout Lake. Mineralization consists of disseminated pyrite and chalcopyrite. A chip sample across the vein taken by the author returned 0.40 percent copper and a grab sample of more highly mineralized material 0.34 percent copper (assays by the Geoscience Laboratories). Negligible gold values were reported (Thurston et al., 1979).
| Rank | Classification |
|---|---|
| 1 | Vein |
| Rank | Characteristic |
|---|---|
| 1 | Vein |
Map - Big Trout Lake-North Caribou Lake, geological compilation series, Kenora District
Publication Number: M2292 Scale: 1:253,440 Date: 1974
Author: Bennett G., Riley R.A., Thurston P.C., Siragusa G.M., Sage R.P.
Publisher Name: Ontario Division of Mines
Location:
MonoMap - Geology of Winisk Lake area, District of Kenora, Patricia Portion
Publication Number: R193 Scale: Date: 1980
Author: Thurston P.C., Sage R.P., Siragusa G.M.
Publisher Name: Ontario Geological Survey
Location:
Map - Geological series, Operation Winisk Lake, Wunnummin Lake-Big Trout Lake, District of Kenora (Patricia Portion)
Publication Number: P0712 Scale: 1:126,720 Date: 1997
Author: Thurston P.C., Sage R.P., Siragusa G.M.
Publisher Name: Ontario Dept. of Mines and Northern Affairs
Location:
MonoMap - Geology of the Big Trout Lake area, District of Kenora (Patricia Portion)
Publication Number: R023 Scale: Date: 1997
Author: Hudec P.P.
Publisher Name: Ontario Dept. of Mines
Location:
Map - Big Trout Lake area, Kenora District, Patricia Portion
Publication Number: M2045 Scale: 1:126,720 Date: 1997
Author: Hudec P.P.
Publisher Name: Ontario Dept. of Mines
Location:
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