Ontario Mineral Inventory

Ontario Geological Survey
Permanent Link to this Record: MDI000000001878

Record: MDI000000001878

General

Commodities

Primary Commodities: Copper

Location

Township or Area: Oskabukuta Lake Area, Laberge

Latitude: 48° 37' 26.05"    Longitude: -85° 41' 56.14"

UTM Zone: 16    Easting: 595877   Northing: 5386465    UTM Datum: NAD83

Resident Geologist District: Thunder Bay South

NTS Grid: 42C12NE, 42C12SE

Point Location Description: M2416

Location Method: Data Compilation

Access Description: A logging road from the village of Mobert passes near the southeastern side of the property. Access to carry out work on the property is best gained by float plane into Fearless Lake.

Exploration History

1984: New Forty Four Mines ltd. conducted geological mapping, prospecting, line cutting, and geophysical surveys.

Assessment Work on File

Geology

Province: Superior

Subprovince: Wawa

Terrane: Wawa-Abitibi

Belt: Schreiber-Hemlo

Geological Age: Archean  

Lithology

Lithology Comments

Jan 12, 2016 (Therese Pettigrew) - Strongly sheared, altered granite gneiss breccia in contact with diabase (M2614). The property is underlain by the Pukaskwa Gneissic Complex. The granitic terrain on the claims is well exposed in most areas and occurs as featureless, massive, white to pink porphyritic granodiorite to well foliated-gneissic granite. Irregular knots and bands of quartz veins were observed in several places. A massive monfoliated, dark green, medium-grained diabase dyke occurs near the west center of the property. The dyke is well exposed on the northern shore of a small beaver pond. Here the dyke is over 100 feet wide and was traced for about 1300 feet to the southeast. Contact relations are obscured by overburden. In several localities, significant (about 2-5%) pyrite was noted in the dyke. Several grab samples of pyritic diabase returned only background levels of gold and silver. Only one fault-shear zone was observed on the property. This coincides with the above mentioned diabase dyke. The shear trends about 320 degrees and dips vertical to 80 degrees S and can he traced to the north into Pickeral Bay and to the south near a logging road for a strike length of over 10,000 feet. At the beaver pond, the shear occurs entirely within the diabase dyke which in the immediate vicinity of the shear has been strongly carbonatized and silicified and in places is mylonitic (AFRI 42C12SE0010).

Mineralization

Mineralization Comments

Jan 12, 2016 (Therese Pettigrew) - Up to 6% pyrite and chalcopyrite in carbonate veinlets. Up to 0.4% Cu (M2614). Two areas containing mineralization were discovered on the claims during the 1984 property evaluation. The most significant of these lies under about three to five feet of water in a beaver pond. Detailed mapping and prospecting along the shear zone mentioned above located minor carbonate alteration in the diabase dyke on the north shore of the beaver pond. As the shear zone appeared to lie in the pond, the beaver dam was broken and the water level dropped about six feet. The shear, containing significant pyrite and chalcopyrite mineralization, was then observed about 10 to 80 feet south of the shore line. Mineralization is found in two shears along a length of about 450 feet. The main shear occurs along the north shore of the pond and ranges from two to over ten feet wide. It occurs as a reddish-brown carbonatized altered and mylonitic crushed zone with numerous veinlets and crystals of tourmaline and epidote. Joints and tension gashes are filled with calcite (70%) and quartz (30%). The diabase is nonmagnetic where strongly altered (hematitized) but is weakly magnetic in fresh unaltered outcrop. Mineralization consists of both smeared and well developed cubic and tetrahedron crystals of pyrite and chalcopyrite (up to 10mm) in calcite veinlets and minor specks of cubic galena. Six samples, both chip-channels and selected grabs, were taken from this zone. Sample 2202, consisting of selected pieces of carbonatized, silicified sheared diabase with abundant calcite veinlets containing about 5% pyrite and 1% chalcopyrite gave the best assay obtained; 0.40% Cu, 0.027 oz/ton Ag and 10 ppb Au. This shear was traced 230 feet to the northwest where a similiar style alteration and mineralization was noted. Sample 2206 is a grab sample of silicified sheared diabase and assayed 0.04% Cu, trace Ag and 10 ppb Au. Sample 2214, taken at the eastern end of the shear assayed 0.193% Cu, 0.015 oz/ton Ag and 2 ppb Au. A subsidiary shear trending about 290 degrees and dipping about 65 degrees N occurs near the west end of the beaver pond. The shear is about one to three feet wide in diabase which is strongly carbonatized, silicified and mylonitized over about four feet. Mineralization consists of smeared pyrite and chalcopyrite in altered diabase and calcite filled tension gashes. Minor malachite and azurite and a few crystals of bornite were noted. Sample 2204 is a chip sample across one foot of mylonite containing 3% to 5% pyrite/chalcopyrite. It assayed 0.055% Cu, trace Ag and 8 ppb Au. Sample 2215 consists of selected pieces of altered diabase containing about 3% to 5% pyrite/chalcopyrite in calcite-filled gashes. Assays yielded 0.32% Cu, 0.017 oz/t Ag and 2 ppb Au (AFRI 42C12SE0010).

Mineral Record Details

References

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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For detailed information regarding this mineral record please contact the Thunder Bay South Resident Geologist District Office