Ontario Geological Survey
Permanent Link to this Record:
MDI000000001877
| Record Name(s) | Baseline Moly - 1982, White River Claims - 1982 |
|---|---|
| Related Record Type | |
| Record Status | Discretionary Occurrence |
| Date Created | 2016-Jan-12 |
| Date Last Modified | 2021-Dec-06 |
| Created By | Therese Pettigrew |
| Revised By | Therese Pettigrew |
Primary Commodities: Molybdenum
Township or Area: Bomby
Latitude: 48° 40' 36.27" Longitude: -85° 53' 38.56"
UTM Zone: 16 Easting: 581414 Northing: 5392112 UTM Datum: NAD83
Resident Geologist District: Thunder Bay South
NTS Grid: 42C12NW
Point Location Description: M2416
Location Method: Data Compilation
1981: Lac Minerals Ltd. conducted airborne geophysical surveys (mag, EM, RAD). 1982: Lac Minerals conducted geological mapping, geochemical soil sampling, and ground geophysical surveys (VLF-EM, magnetometer and IP). 1983: Lac Minerals Ltd. conducted geological mapping, soil sampling and trenching. 1984: Lac Minerals drilled 1 DDH totaling 216 m.
| Office File Number | Online Assessment File Identifier | Online Assessment File Directory |
|---|---|---|
| 42C12NW0039A1 | 42C12NW0039 | 42C12NW0039 |
| 42C12NW0063A1 | 42C12NW0186 | 42C12NW0186 |
| 42C12NW0054 | 42C12NW0073 | 42C12NW0073 |
| 42C12NE0030 | 42C12NW0013 | 42C12NW0013 |
| 2.7111 | 42C12NE8697 | 42C12NE8697 |
| 42C12NE0048 | 42C12NE0060 | 42C12NE0060 |
Province: Superior
Subprovince: Wawa
Terrane: Wawa-Abitibi
Belt: Schreiber-Hemlo
Geological Age: Archean
| Rock Type | Rank | Composition | Texture | Relationship | Sandstone | 1 | Lithic Wacke | Host |
|---|---|---|---|---|
| Mafic lava flow-unsubdivided | 2 | Adjacent |
Jan 12, 2016 (Therese Pettigrew) - North of the mafic volcanic contact the sedimentary rock unit is comprised of lithic and feldspathic wacke and lithic and feldspathic quartzites. The lithic wackes are green to grey weathering with parallel layers of sericite locally. Acicular amphibole and quilts of biotite also align themselves along these sericitic layers. The feldspathic wackes weather brownish grey and are more structurally competent than the lithic wacke. Amphibole layers from 0.5 to 1.0 cm thick are characteristic of this rock. Both types of wacke are quartz poor. Textures indicating soft sediment deformation are present locally. The lithic and feldspathic quartzites contain up to 75% quartz and are distinguished from each other by their accessory amounts of feldspar or mafic lithic grains. Amphibole layers consisting of prismatic amphiboles in feldspar-rich matrix with no carbonate occur locally. The quartzites generally display silicified joint systems at high angle to bedding. Compositional banding is also evident by blebs of pyrite concentrated within certain layers. Quartzites are more predominant in the upper 100 m of the sedimentary rock unit. The quartzites are massive or banded with quartzite layers 10 to 100 cm thick separated by layers of lithic wacke. Also, in the northern half of the sedimentary rock unit is an intermediate (and minor amounts of felsic) volcanic rock which has a 400 m long lensoidal outcrop pattern. A medium-grained magnetic diabase dyke strikes 010 degrees and crosscuts both sedimentary and volcanic rocks. Carbonate-diopside rock is at the south contact of sedimentary rock and the north contact of the upper mafic rock unit. This rock is khaki green on weathered surface and contains coarsely crystalline green, brown and white minerals thought to be diopside, andalusite or vesuviante and calcite respectively. Calcite occurs in patches, lenses and veins. Black, zoned tourmaline, 1.0 to 1.5 cm long is an accessory mineral. This rock outcrops in the east central portion of claim SSM 625563 and extends to the southeast portion of claim SSH 625564. The carbonate diopside unit varies in outcrop thickness from 1 to 20 m. The south part of this unit is more chlorite-rich, schistose and free of cross-cutting calcite veinlets whereas the north part contains gently folded bands of diopside and andalusite or vesuvianite with up to 5% carbonate occurring as cross-cutting veinlets, dolomitic to calcitic layers and feathery patches along layering. Also, at the south, pyrite and pyrrhotite are disseminated in 3 to 30 cm thick bands. Carbonate-free, chlorite-actinolite schist occurs as 1 to 15 cm thick layers within carbonate-diopside rock whereas carbonate-diopside rock adjacent to these layers may contain up to 10% carbonate (AFRI 42C12NW0039).
| Rank | Mineral Name | Class | Economic Mineral Type | Alteration Mineral Type | Alteration Ranking | Alteration Intensity | Alteration Style |
|---|---|---|---|---|---|---|---|
| 1 | Pyrite | Economic | Ore | ||||
| 2 | Molybdenite | Economic | Ore | ||||
| Carbonate | Alteration | Carbonatization | 1 |
Jan 12, 2016 (Therese Pettigrew) - Disseminated molybdenum and pyrite in quartz veins in lithic wacke interbedded with siltstone (M2614). Molybdenite is the predominant sulphide at the north part of the carbonate-diopside unit and occurs as disseminated blebs in andalusite or vesuvianite or as platey layers along the contact between diopside and andalusite or vesuvianite. In both cases calcite is associated with the sulphide (AFRI 42C12NW0039). Soil samples returned assays of 5-9 ppm Mo.
Map - Geological Compilation of the Eastern Half of the Schreiber-Hemlo Greenstone Belt
Publication Number: M2614 Scale: 1:50,000 Date: 2000
Author: Muir T.L.
Publisher Name: Ontario Geological Survey
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