Ontario Geological Survey
Permanent Link to this Record:
MDI41N11SE00008
| Record Name(s) | Island South of Jordan Island - 1961 |
|---|---|
| Related Record Type | Simple |
| Related Record(s) | |
| Record Status | Occurrence |
| Date Created | 2000-Apr-07 |
| Date Last Modified | 2022-Jul-14 |
| Created By | |
| Revised By |
Primary Commodities: Manganese, Hematite (Gemstones)
Township or Area: Alarie
Latitude: 47° 35' 3.9" Longitude: -85° 1' 35.95"
UTM Zone: 16 Easting: 648378.6 Northing: 5271998.47 UTM Datum: NAD83
Resident Geologist District: Sault Ste. Marie
NTS Grid: 41N11SE
Point Location Description: Vein on island
Location Method: Data Compilation
Access Description: The island is located in Lake Superior Provincial Park. The site is most easily accessed by gravel road (Gargantua Road) from Highway 17 for a distance of 15 km to Gargantua Harbour. From the harbour, the island is located approximately 5 km north east and can be accessed by kayak or canoe.
No exploration has been reported on the island although it is presumed that prospecting has taken place in the area since approximately 1860.
Province: Southern
Supergroup: Keweenawan Supergroup
Geological Age: Mesoproterozoic Geochronological Age: 1.10 MA Geochron. Age Ref.: GOO VOL 1
Dec 07, 2005 (A Wilson) - The rocks of the Keweenawan Supergroup were deposited in and marginal to the Midcontinent Rift at approximately 1.1 Ga. They unconformably overlie the migmatites of the Ryan Mineral Location.
| Rock Type | Rank | Composition | Texture | Relationship | Breccia-unsubdivided | 1 | Rhyolite | Host |
|---|---|---|---|---|
| Felsic lava flow-unsubdivided | 2 | Host | ||
| Vein | 3 | Calcite | Host |
Dec 07, 2005 (A Wilson) - Mineralization is hosted by a breccia zone consisting of quartz, coarse-grained calcite and rhyolite. The breccia zone ranges in width from less than 1 inch to 4 feet. It is hosted within a complexly folded and flow banded, fine-grained rhyolite. The rhyolite contains phenocrysts of feldspar and hematite.
| Rank | Mineral Name | Class | Economic Mineral Type | Alteration Mineral Type | Alteration Ranking | Alteration Intensity | Alteration Style |
|---|---|---|---|---|---|---|---|
| 1 | Hematite | Economic | Ore | ||||
| 2 | Manganite | Economic | Ore | ||||
| 1 | Calcite | Economic | Gangue | ||||
| 2 | Quartz | Economic | Gangue |
Dec 07, 2005 (A Wilson) - Lenses of hematite and manganite, up to 1 inch in width, are located within and paralle to the breccia zone. A grab sample collected by the OGS in 1961 returned a value of 5.31% Mn and 11.79% Fe.
| Rank | Classification |
|---|---|
| 1 | Hydrothermal |
| Rank | Characteristic |
|---|---|
| 2 | Breccia |
| 1 | Vein |
| Shape | Length | Thickness | Depth | Strike | Dip | Plunge | Trend | Age | Reference |
|---|---|---|---|---|---|---|---|---|---|
| Irregular | 50 | .6 | 1.10 MA | GOO VOL 1 |
Compend - Geology of Ontario [part 1]
Publication Number: SV04-01 Date: 1991
Author: Thurston P.C., Williams H.R., Sutcliffe R.H., Stott G.M.
Publisher Name: Ontario Geological Survey
Location:
Map - Township 31, Range 19 [Alarie Township], District of Algoma
Publication Number: P0128 Scale: 1:15,840 Date: 1997
Author: Ayres L.D.
Publisher Name: Ontario Dept. of Mines
Location:
MonoMap - Geology of townships 31 and 30, ranges 20 and 19, District of Algoma
Publication Number: R069 Page: 81 Date: 1969
Author: Ayres L.D.
Publisher Name: Ontario Dept. of Mines
Location:
Map - Townships 31 and 30, range 19, Algoma District
Publication Number: M2138 Scale: 1:31,680 Date: 1968
Author: Ayres L.D.
Publisher Name: Ontario Dept. of Mines
Location:
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