Ontario Geological Survey
Permanent Link to this Record:
MDI52O03NE00005
| Record Name(s) | South Dunlop Lake - 1990, Drum Lake # 1 - 1990, Ontario Gold Joint Venture - 9999 |
|---|---|
| Related Record Type | Simple |
| Related Record(s) | |
| Record Status | Occurrence |
| Date Created | 1990-Nov-28 |
| Date Last Modified | 2023-Aug-03 |
| Created By | |
| Revised By |
Primary Commodities: Gold
Township or Area: Drum Lake Area
Latitude: 51° 14' 3.7" Longitude: -91° 1' 16.69"
UTM Zone: 15 Easting: 638137.752 Northing: 5677747.417 UTM Datum: NAD83
Resident Geologist District: Thunder Bay North
NTS Grid: 52O03NE
Point Location Description: Outcrop just southeast of small lake that is 2 km south of Mousetrap Lake on map 2507.
Location Method: Data Compilation
Access Description: The occurrence is located about 61 km southwest of Pickle Lake. The occurrence is found off the southeast end of a small un-named lake about 2 km south of Mousetrap Lake. The small un-named lake is locally known as Dunlop Lake. The occurrence may be reached by appropriately equipped aircraft to Mousetrap Lake. A trail which starts at the west end of Mousetrap Lake may be followed to the occurrence. Small helicopters may be able to land on the occurrence outcrop.
1972: Cochenour Willans Gold Mines Ltd. and Selco Exploration Company Ltd., in joint venture, did an airborne geophysical survey of the area and followed up with ground magnetometer and electromagnetic surveys in the Dunlop Lake area. 1978: Cominco Ltd. commissioned an airborne magnetometer survey over the Dunlop Lake area. 1979: Cominco Ltd. did ground magnetometer, electromagnetic, and gravity surveys and geological mapping on claims covering the South Dunlop Lake occurrence. 1981: Cominco Ltd. drilled a 99 m diamond-drill hole west of the South Dunlop Lake occurrence. 1984-1988: The Ontario Gold Joint Venture (Northern Dynasty Exploration Ltd., Westfield Minerals Ltd. and Newfield Minerals Inc.) conducted a multi-phased exploration program on claims covering the South Dunlop Lake occurrence. The work included airborne magnetometer and electromagnetic survey, ground magnetometer and electromagnetic surveys, geological mapping, rock and soil geochemistry, stripping and trenching, sampling and 3 diamond-drill holes totalling 144.47 m. 1986: Geocanex Ltd. commissioned airborne magnetometer and electromagnetic surveys over an area which included the South Dunlop Lake occurrence.
Province: Superior
Subprovince: Uchi
Terrane: North Caribou
Domain: Uchi
Belt: Meen-Dempster
Geological Age: Neoarchean
Dec 07, 2005 (B Nelson) - The occurrence consists of several deformed quartz-tourmaline-pyrite veins contained within a 15 m wide intensely deformed, silicified felsic metavolcanic unit. Intensely deformed mafic metavolcanics outcrop to the south of the silicified felsic metavolcanics. Intensely deformed intermediate to felsic metavolcanics outcrop to the north of the silicified felsic metavolcanics. The second deformation event was so intense that, in the vicinity of the occurrence, primary textures and early deformation fabrics were masked. A well developed slaty cleavage is the prominent structural feature of the rocks around the occurrence. The cleavage planes are 3 to 10 mm apart. They strike 125 degrees and dip 83 degrees south within the silicified felsic metavolcanics. Occassional narrow fault breccia zones, that cut subparallel to the cleavage, cut the silicified felsic metavolcanics. The cleavage does not penetrate the fault breccia. The latest structural feature observed in the vicinity of the occurrence is a set of conjugate kink bands in the cleavage planes. The conjugate kink bands strike 000 degress and 090 degrees and dip 65 degrees west and 65 degrees east, respectively. The quartz-tourmaline-pyrite veins, which contain the gold at the South Dunlop Lake occurrence, trend east and dip north. The veins are highly contorted and are penetrated by the cleavage. They average less than 30 cm in thickness and do not extend beyond the silicified felsic metavolcanics. The veins are offset by the fault breccia zones. The apparent offset is left-handed which does not conform to the ideas of Stott and Wilson (1986a, 1986b), who mapped the sense of movement within the deformation zone as right-handed. Also interesting are the narrow (1.0 cm), short (less than 3 m) east-trending quartz veins within the mafic metavolcanics; and quartz feldspar dykes along the contact of the silicified felsic metavolcanics and the intermediate to felsic metavolcanics.
| Rock Type | Rank | Composition | Texture | Relationship | Felsic lava flow-unsubdivided | 1 | Host |
|---|---|---|---|---|
| Mafic lava flow-unsubdivided | 2 | Near | ||
| Intermediate lava flow-unsubdivided | 3 | Near | ||
| Quartz-Feldspar Porphyry | 4 | Quartz-Feldspar Porphyry | Near |
| Rank | Mineral Name | Class | Economic Mineral Type | Alteration Mineral Type | Alteration Ranking | Alteration Intensity | Alteration Style |
|---|---|---|---|---|---|---|---|
| 1 | Pyrite | Economic | Ore | ||||
| Quartz | Alteration | Silicification | 1 | ||||
| Unspecified | Alteration | Sericitization | 2 |
Dec 07, 2005 (B Nelson) - Mineralization occurs in a shear zone. The quartz-tourmaline-pyrite veins, which contain the gold at the South Dunlop Lake occurrence, trend east and dip north. Northern Dynasty Explorations Ltd. reported that individual grab samples of the veins assayed up to 0.52 oz/ton Au. The panel samples that included the silicified felsic metavolcanic and vein material returned less than 100 ppb gold. The Sioux Lookout Staff Geologist took 4 grab samples from this occurrence for assay. The best assay was 630 ppb Au from a sample of the vein.
| Rank | Classification |
|---|---|
| 1 | Lode (Gold) |
| Rank | Characteristic |
|---|---|
| 1 | Sheared |
| 2 | Vein |
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:
MonoMap - Geology of the Cat Lake-Pickle Lake area, districts of Kenora and Thunder Bay
Publication Number: R207 Date: 1982
Author: Sage R.P., Breaks F.W.
Publisher Name: Ontario Geological Survey
Location:
Article - Sioux Lookout Resident Geologist's District - 1989
Publication Number: MP147.004 Page: 87-88 Date: 1997
Author: Janes D.A., Seim G.Wm., Storey C.C.
Publisher Name: Ontario Geological Survey
Location:
Map - Precambrian geology, Muskegsagagen-Bancroft lakes area, District of Kenora (Patricia Portion)
Publication Number: M2507 Scale: 1:50,000 Date: 1986
Author: Stott G.M., Wilson A.C.
Publisher Name: Ontario Geological Survey
Location:
Mono - Mineral Deposits of the Central Portion of Uchi Subprovince, Volume 1, Meen Lake to Kesagiminnis Lake Portion
Publication Number: OFR5869 Page: 61 Date: 1993
Author: Seim G.Wm.
Publisher Name: Ontario Geological Survey
Location:
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