Ontario Geological Survey
Permanent Link to this Record:
MDI52O01SW00003
| Record Name(s) | Lake St. Joseph North Zone - 1985, Soules Bay - 1985 |
|---|---|
| Related Record Type | Partial |
| Related Record(s) | |
| Record Status | Developed Prospect With Reported Reserves or Resources |
| Date Created | 1985-Jul-29 |
| Date Last Modified | 2023-Mar-23 |
| Created By | |
| Revised By |
Primary Commodities: Iron
Township or Area: Riach Lake Area
Latitude: 51° 2' 28.19" Longitude: -90° 28' 55.3"
UTM Zone: 15 Easting: 676516.86 Northing: 5657419.38 UTM Datum: NAD83
Resident Geologist District: Thunder Bay North
NTS Grid: 52O01SW
Point Location Description: Precise
Location Method: Conversion from MDI
| Office File Number | Online Assessment File Identifier | Online Assessment File Directory |
|---|---|---|
| 52O02SE0013 | 52O01SW0006 | 52O01SW0006 |
| 52O01SW0014C1 | 52O01SW0003 | 52O01SW0003 |
| 52O01SW13 | 52O01SW9443 | 52O01SW9443 |
Province: Superior
Subprovince: Uchi
Terrane: North Caribou
Domain: Uchi
Belt: Lake St. Joseph
Geological Age: Neoarchean
Jun 21, 2007 (Mark Puumala) - The Lake St. Joseph iron prospect consists of two low-grade magnetite iron formation deposits (North and South Zones) hosted within a clastic metasedimentary rock-dominated sequence (Goodwin 1965). The metasedimentary sequence is reported to consist of a variety of lithologies ranging from conglomerate to argillite, and is intercalated with metavolcanic tuff and amphibolite units. The iron formations are reported by Goodwin (1965) to be closely associated with argillaceous schist units that occur near the upper (northern) contact of the metasedimentary sequence with an overlying metavolcanic rock-dominated assemblage. The iron formation is described by Goodwin (1965) as banded iron formation consisting of alternating 1 to 25 cm thick layers of black magnetite-rich material, white quartz-rich layers, and grey, green or brown silicate-rich (clastic sediment-dominated) layers. The richest zones in each iron formation (i.e., with highest concentration of magnetite layers) are reported to occur near the northern contacts of each deposit. Goodwin (1965) reports that the rocks of this area lie on the north limb of an east-northeast-trending, and east-northeast-plunging (35 to 60 degrees) anticline. This limb of the structure is overturned, with bedding generally reported to dip between 60 to 80 degrees toward the south. Smaller-scale complex folding of the iron formation is also reported by Goodwin (1965), with numerous reversals in younging direction noted in various portions of the deposits.
| Rock Type | Rank | Composition | Texture | Relationship | Ironstone-unsubdivided | 1 | Is |
|---|---|---|---|---|
| Sandy Conglomerate | 2 | Conglomerate To Argillite | Adjacent | |
| Intermediate Tuff | 3 | Tuff | Near | |
| Amphibolite | 4 | Amphibolite | Near |
| Rank | Mineral Name | Class | Economic Mineral Type | Alteration Mineral Type | Alteration Ranking | Alteration Intensity | Alteration Style |
|---|---|---|---|---|---|---|---|
| 1 | Magnetite | Economic | Ore |
Jun 21, 2007 (Mark Puumala) - Goodwin (1965) reports that the North Zone deposit has a strike-length of approximately 3.23 km, and has a width that ranges from 150 to 360 m. Diamond drilling is reported to have indicated that the deposit is continuous to a minimum depth of 150 m. The strike direction varies from approximately 075 at the east end of the deposit to 105 at the west end, while the dip varies from 55 to 80 degrees toward the south. Sage and Breaks (1982) report a reserve estimate of 348,105,000 tonnes grading 23.78% Fe for the North Zone (to a depth of 122 m), with an additional 66,103,000 tonnes of ore having an unknown grade estimated to the 213 m level.
| Rank | Classification |
|---|---|
| 1 | Sedimentary |
| Rank | Characteristic |
|---|---|
| 1 | Stratabound |
| Zone | Year | Category | Tonnes | Reference | Comments | Commodities |
|---|---|---|---|---|---|---|
| North Zone from 122 to 213 m | 1982 | Unclassified | 66103000 | Sage and Breaks (1982). | Unknown grade. Reserve calculation pre-dates NI 43-101. | |
| North Zone | 1982 | Unclassified | 348105000 | Sage and Breaks (1982). | Estimated grade of 23.78% Fe. Reserve calculation pre-dates NI 43-101. |
Map - Cat Lake-Pickle Lake, geological compilation series, Kenora and Thunder Bay districts
Publication Number: M2218 Scale: 1:253,440 Date: 1976
Author: Sage R.P., Breaks F.W., Troup W.R.
Publisher Name: Ontario Division of Mines
Location:
Mono - Iron deposits of Ontario
Publication Number: MDC011 Page: 455 Date: 1968
Author: Shklanka R.
Publisher Name: Ontario Dept. of Mines
Location:
MonoMap - Geology of the Cat Lake-Pickle Lake area, districts of Kenora and Thunder Bay
Publication Number: R207 Page: 134-140 Date: 1982
Author: Sage R.P., Breaks F.W.
Publisher Name: Ontario Geological Survey
Location:
MonoMap - Geology of Pashkokogan Lake-eastern Lake St. Joseph area, districts of Thunder Bay and Kenora
Publication Number: R042 Date: 1997
Author: Goodwin A.M.
Publisher Name: Ontario Dept. of Mines
Location:
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