Ontario Geological Survey
Permanent Link to this Record:
MDI42C03SW00008
| Record Name(s) | Northwest Occurrence - 1982 |
|---|---|
| Related Record Type | Simple |
| Related Record(s) | |
| Record Status | Occurrence |
| Date Created | 1991-Jan-08 |
| Date Last Modified | 2022-Sep-12 |
| Created By | |
| Revised By |
Primary Commodities: Gold
Township or Area: Mishibishu Lake Area
Latitude: 48° 5' 49.97" Longitude: -85° 24' 11.65"
UTM Zone: 16 Easting: 618885.91 Northing: 5328338.32 UTM Datum: NAD83
Resident Geologist District: Sault Ste. Marie
NTS Grid: 42C03SW
Point Location Description: Trenches SE of Question Mark Lake
Location Method: Based on Assessment
Access Description: Drive west along highway 17 from the junction of highway 17 and 101 for approximately 50 km to the Paint Lake Road (a gravel road heading south from highway 17). Drive south along the gravel road for approximately 55 km to the Eagle River Mill site. The showing is located approximately 3 km SE of the mill. Alternatively, the site is accessible by helicopter from Wawa.
1981-84: Westfield Minerals Ltd. and St. Fabien Exploration Inc. - mapping, ground geophysics, geochemistry, trenching, 7 ddh (1986 ft). 1983: MacMillan Energy - airborne geophysics. 1994: MacMillan Gold Corp. and Granges Inc. - airborne geophysics.
| Office File Number | Online Assessment File Identifier | Online Assessment File Directory |
|---|---|---|
| Mishibishu Lake 0025 | 42C03SW0108 | 42C03SW0108 |
| Mishibishu Lake 0023 | 42C03SW0109 | 42C03SW0109 |
| Mishibishu Lake 0022 | 42C03SW0103 | 42C03SW0103 |
| Mishibishu Lake 0021-B1 | 42C03SW0106 | 42C03SW0106 |
| Mishibishu Lake 0017 | 42C03SW0116 | 42C03SW0116 |
| WP Mishibishu Lake.42 | 42C03SE2001 | 42C03SE2001 |
| Groseilliers-0015 | 42C03SE0013 | 42C03SE0013 |
Province: Superior
Subprovince: Wawa
Terrane: Wawa-Abitibi
Belt: Michipicoten
Tectonic Assemblage: Catfish
Geological Age: Neoarchean Geochronological Age: 2.7 GA Geochron. Age Ref.: GOO VOL 1
Dec 07, 2005 (A Wilson) - The Mishibishu Deformation Zone (MDZ) is the largest of the deformation zones int he belt, measuring approximately 40 km in length and several hundred metres up to 1.5 km in width. The zone is located north of the Mishibishu Lake stock, and lies along the lithological contact of mafic metavolcanic rocks to the north and clastic metasediments to the south. The central MDZ has the highest degree of strain intensity and alteration within the belt. Shear zones are broad and exhibit pervasive deformation and alteration. Mafic metavolcanics in the hanging wall become progressively more strained and altered with increasing proximity to the centre of the zone. Conglomerate clasts are attenuated and only the most competent clasts are discernable from matrix. An intense penetrative foliation strikes approximately 300 and a well developed stretching lineation plunges moderately to the N and NE.
| Rock Type | Rank | Composition | Texture | Relationship | Schist-Unsubdivided | 1 | Chlorite-Sericite-Carb | Host |
|---|---|---|---|---|
| Intermediate Tuff-Breccia | 2 | Tuff, Breccia | Hanging Wall |
Dec 07, 2005 (A Wilson) - The occurrence is hosted within intensely altered and deformed rocks consisting of schists made up of variable amounts and combinations of chlorite, sericite, ankerite, quartz, calcite, green mica, feldspar and pyrite. The only relict primary lithologies recognized at the showing are altered and deformed polymictic and oligomictic conglomerates. To the north, the showing is bounded by intermediate to mafic metavolcanic rocks (lapilli tuff, volcanic breccia, crystal tuff, massiv flows and gabbro). As the MDZ is approached, these rocks exhibit a more pronounced penetrative foliation. The intensely altered and deformed rocks grade southward into less deformed and altered rock, exhibiting relict sedimentary textures.
| Rank | Mineral Name | Class | Economic Mineral Type | Alteration Mineral Type | Alteration Ranking | Alteration Intensity | Alteration Style |
|---|---|---|---|---|---|---|---|
| 1 | Pyrite | Economic | Gangue | ||||
| 2 | Arsenopyrite | Economic | Gangue | ||||
| 3 | Chalcopyrite | Economic | Gangue | ||||
| 4 | Galena | Economic | Gangue | ||||
| Chlorite | Alteration | Chloritic | 1 | Strong | Replacement | ||
| Calcite | Alteration | Carbonatization | 2 | Strong | Replacement | ||
| Ankerite | Alteration | Carbonatization | 3 | Strong | Replacement | ||
| Fuchsite | Alteration | Carbonatization | 4 | Strong | Replacement |
Dec 07, 2005 (A Wilson) - Assays returned from samples collected by Westfield Minerals in 1982 from trenches returned assays ranging from 0.03 oz/t Au over 20 cm to 0.23 oz/t Au over 20 cm. Small scale, discontinuous quartz veins have yielded assays of 1.57 oz/t Au from a grab sample and 0.53 oz/t Au over 4 ft. Diamond drilling by Westfield returned assays up to 0.04 oz/t Au over 2 ft in sheared intermediate metavolcanic rocks.
| Shape | Length | Thickness | Depth | Strike | Dip | Plunge | Trend | Age | Reference |
|---|---|---|---|---|---|---|---|---|---|
| Regular | 152.4 |
Map - University River, Algoma and Thunder Bay districts
Publication Number: M2333 Scale: 1:63,360 Date: 1976
Author: Bennett G., Thurston P.C., Giguere J.F.
Publisher Name: Ontario Division of Mines
Location:
Map - Operation Pukaskwa, University River sheet, districts of Thunder Bay and Algoma
Publication Number: P0507 Scale: 1:63,360 Date: 1997
Author: Bennett G., Thurston P.C., Giguere J.F.
Publisher Name: Ontario Dept. of Mines
Location:
Map - Operation Pukaskwa, districts of Algoma and Thunder Bay
Publication Number: P0541 Scale: 1:126,720 Date: 1997
Author: Bennett G., Thurston P.C., Giguere J.F.
Publisher Name: Ontario Dept. of Mines
Location:
Map - Geological series, Precambrian geology, Mishibishu Lake area, northeastern section, districts of Thunder Bay and Algoma
Publication Number: P2970 Scale: 1:15,840 Date: 1986
Author: Bowen R.P., Logothetis J., Heather K.B.
Publisher Name: Ontario Geological Survey
Location:
Map - Precambrian geology, Mishibishu Lake area, Mishibishu Lake sheet
Publication Number: P3152 Scale: 1:15,840 Date: 1992
Author: Reid R.G., Bowen R.P., Heather K.B., Logothetis J., Reilly B.A.
Publisher Name: Ontario Geological Survey
Location:
Map - Marginal notes, Mishibishu Lake area
Publication Number: P3184 Date: 1992
Author: Reid R.G., Bowen R.P., Heather K.B., Logothetis J., Reilly B.A.
Publisher Name: Ontario Geological Survey
Location:
Folio - Mishibishu Lake area, Sault Ste. Marie Mining Division, NTS No. 42C/03SW
Publication Number: GDIF597 Date: 1997
Author: Wawa RGO
Publisher Name: Ontario Geological Survey
Location:
Map - Mishibishu Lake area, District of Thunder Bay, Ontario
Publication Number: ARM49J Scale: 1:63,360 Date: 1997
Author: Evans E.L.
Publisher Name: Ontario Dept. of Mines
Location:
Article - Gold showings of the Mishibishu Lake area, Thunder Bay District
Publication Number: MP126.015S Page: 87-88 Date: 1997
Author: Heather K.B.
Publisher Name: Ontario Geological Survey
Location:
Mono - Wawa mineral deposits data base
Publication Number: OFR5775 Page: 284 Date: 1991
Author: Frey E.D., Stewart R.C.
Publisher Name: Ontario Geological Survey
Location:
Mono - Geology, structure and economic geology of the Mishibishu Lake area
Publication Number: OFR5774 Page: 210-219 Date: 1991
Author: Reid R.G., Bowen R.P., Reilly B.A., Logothetis J., Heather K.B.
Publisher Name: Ontario Geological Survey
Location:
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