Ontario Geological Survey
Permanent Link to this Record:
MDI000000001266
| Record Name(s) | Lake Clear - 1981, OGS Sample T-246A - 1978 |
|---|---|
| Related Record Type | |
| Related Record(s) | |
| Record Status | Occurrence |
| Date Created | 2011-Jun-06 |
| Date Last Modified | 2023-Jun-16 |
| Created By | |
| Revised By |
Primary Commodities: Thorium
Secondary Commodities: Uranium, Rare Earth Elements
Township or Area: Sebastopol
Latitude: 45° 24' 59.61" Longitude: -77° 13' 7.45"
UTM Zone: 18 Easting: 326402 Northing: 5031621.002 UTM Datum: NAD83
Resident Geologist District: Southern Ontario
NTS Grid: 31F06NE
Point Location Description: approximate
Location Method: Data Compilation
1977: Ontario Geological Survey - sampling, analysis
Province: Grenville
Subprovince: Central Metasedimentary Belt
Geological Age: Mesoproterozoic
Jun 16, 2023 (Therese Pettigrew) - The area is underlain by highly metamorphosed metasediments composed dominantly of meta-arkose, with smaller units of marble, paragneiss and calc-silicate rock. The arkosic unit forms the basal portion of the Grenville Supergroup in this area, overlying Middle Precambrian metasediments and intrusive rocks. The Supergroup metasediments in the immediate area of the occurrences are intruded by syenitic rocks and by granite. Late granite pegmatites, calcite-apatite-fluorite veins and pyroxene-biotite veins cut all the above rocks. Two major faults of the Ottawa Bonnechere graben system occur immediately south of the occurrences, and another one immediately north of the occurrences (Masson and Gordon, 1981).
| Rock Type | Rank | Composition | Texture | Relationship | Pegmatite | 1 | Host |
|---|---|---|---|---|
| Quartz Monzonite | 2 | Contains | ||
| Sandstone | 3 | Arenite | Gneissic | Contains |
Jun 13, 2011 (A Wilson) - A large quartz monzonite body has intruded syenite and clastic siliceous metasediments. The contact of the metasediments with the quartz monzonite is an area of considerable mixing and local radioactive mineralization is associated with a gradational contact zone from quartz monzonite to arenite. The mixed contact zone contains lenses, irregular pods and patches of pyroxene granophyre and marble, lenses of hornblende-plagioclase gneiss and dikes, veins and patches of granitic and syenitic pegmatite.
| Rank | Mineral Name | Class | Economic Mineral Type | Alteration Mineral Type | Alteration Ranking | Alteration Intensity | Alteration Style |
|---|---|---|---|---|---|---|---|
| 1 | Allanite | Economic | Ore | ||||
| 2 | Chalcopyrite | Economic | Ore | ||||
| 3 | Pyrite | Economic | Ore | ||||
| 4 | Pyrrhotite | Economic | Ore | ||||
| 5 | Thorite | Economic | Ore | ||||
| 6 | Uranothorite | Economic | Ore |
Jun 13, 2011 (A Wilson) - Sample T-246A collected by the OGS in 1978 returned 0.001% U3O8, 0.5% K2O, and 0.039% Th from a pyroxenite dyke. The sample also returned 160 ppm Ce (Themistocleous, 1981).
Jun 16, 2023 (Therese Pettigrew) - Numerous wide-spread radioactive zones, usually less than a square meter, occur within a large body of gneissic pink quartz monzonite. Mineralization also occurs in granite pegmatite and pyroxene veins, especially associated with fracturing. The radioactive minerals are throite, uranothorite, and allanite (Gordon et al., 1981).
| Rank | Classification |
|---|---|
| 1 | Pegmatite |
| Rank | Characteristic |
|---|---|
| 1 | Intrusive |
MonoMap - Geology of the Clontarf area, Renfrew County
Publication Number: R209 Page: 38-45 Date: 1981
Author: Themistocleous S.G.
Publisher Name: Ontario Geological Survey
Location:
Mono - Uranium and thorium deposits of southern Ontario
Publication Number: OFR5311 Page: 621 Date: 1981
Author: Gordon J.B., Rybak U.C., Robertson J.A.
Publisher Name: Ontario Geological Survey
Location:
MonoMap - Radioactive mineral deposits of the Pembroke-Renfrew area
Publication Number: MDC023 Page: 130-131 Date: 1981
Author: Masson S.L., Gordon J.B.
Publisher Name: Ontario Geological Survey
Location:
Map - Geological series, Clontarf area, Renfrew County, southern Ontario
Publication Number: P1560 Scale: 1:15,840 Date: 1978
Author: Themistocleous S.G.
Publisher Name: Ontario Geological Survey
Location:
Map - Clontarf, Renfrew County
Publication Number: M2433 Scale: 1:31,680 Date: 1980
Author: Themistocleous S.G.
Publisher Name: Ontario Geological Survey
Location:
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