Ontario Mineral Inventory

Ontario Geological Survey
Permanent Link to this Record: MDI000000001677

Record: MDI000000001677

General

Commodities

Primary Commodities: Gold

Location

Township or Area: Cotte, Lorna Lake Area

Latitude: 48° 47' 44.76"    Longitude: -86° 12' 56.24"

UTM Zone: 16    Easting: 557605.33   Northing: 5405049.3    UTM Datum: NAD83

Resident Geologist District: Thunder Bay South

NTS Grid: 42D16SE

Point Location Description: 2013 grab sample location adjacent to historic exploration camp.

Location Method: Field Visit with GPS

Access Description: The Wire Lake gold prospect is located approximately 15 km northeast of Marathon and immediately adjacent to Wire Lake. There is no road access to the site, which can be most readily accessed by helicopter or float plane.

Exploration History

1984-95: Carlson Mines Ltd., Black Gregor Mines Ltd. and Gregor Goldfields Corp. - Airborne and ground magnetic and electromagnetic surveys, geological mapping, prospecting, mechanical stripping, soil, humus and stream geochemical surveys, and diamond drilling.

Assessment Work on File

Geology

Province: Superior

Subprovince: Wawa

Terrane: Wawa-Abitibi

Belt: Schreiber-Hemlo

Geological Age: Neoarchean  

Geology Comments

Mar 26, 2014 (Mark Puumala) - The Wire Lake area is underlain by a north-trending supracrustal rock sequence dominated by mafic metavolcanic rocks. These include massive and pillowed flows, with some massive flows grading into coarse-grained mafic rocks (coarse-grained flows or sub-volcanic intrusions) with gabbroic textures. Volcaniclastic and sedimentary rock horizons have also been noted in this sequence, with interflow graphitic argillite and cherty iron formation forming laterally extensive stratigraphic marker horizons (Siriunas 1995). Felsic metavolcanic rocks have been mapped to the west of the mafic metavolcanic dominated sequence that hosts the various occurrences associated with the Wire Lake Prospect, while the area to the east is underlain by porphyritic hornblende quartz monzonite of the Gowan Lake Pluton (Milne 1967). Northeast- and northwest-striking diabase dikes, most likely related to the Proterozoic age Marathon and Pukaskwa swarms respectively, are common on the property. Narrow lamprophyre dikes are also common in the area (Siriunas 1995). Large northwest- and northeast-striking diabase dikes cross-cut the gold mineralized zone at the southeast end of Wire Lake. Gold mineralization at the Wire Lake prospect occurs in four main areas known as the South Lake, Lucky Seven, Candlestick, and North Hill zones. All of these mineralized zones are associated with a 340-striking structure known as the Wire Lake Shear Zone (Siriunas, 1995). The style of mineralization is described by Schneiders and Smyk (1997) as follows: Some local gold occurrences (Figure 5) are associated with fracture-controlled or "tight" quartz± carbonate veins. However, study of the gold occurrences associated with the 2.5 km long Wire Lake shear zone in 1995 (Schnieders and Smyk 1995) and in 1996, by the authors, suggests a protracted deformation, alteration and intrusive history. This structure is characterized by several generations of variably deformed veins, stockwork zones, mafic dykes and extensive, overlapping alteration zones (silicification, carbonatization, sericitization, biotitization). A grab sample of biotitized, silicified and pyritized rock taken from the stripped Candlestick zone (within the Wire Lake shear zone system) returned 0.05 ounce Au per ton. A 4 m chip sample taken across the main mass of quartz-carbonate stockwork veins and altered mafic metavolcanic host rock returned 0.01 ounce Au per ton. South of Wire Lake, a grab sample of the main quartz stockwork and altered, pyritic, mafic metavolcanic rocks within the shear zone returned 0.33 ounce Au per ton. Another 4 m chip sample taken across a pyritic, black slate interflow unit returned 0.03 ounce Au per ton. Assay results for the property compiled by Siriunas (1995) include numerous surface grab sample assays exceeding 1000 ppb (1 g/t) Au, with a maximum reported value of 26743 ppb Au. Some of the most significant drill intersections reported for the four mineralized zones include the following (Siriunas 1995): South Lake Zone - 8.29 g/t Au over 1.22 m; Lucky Seven Zone – 7.07 g/t Au over 2.13 m; Candlestick Zone – 6.12 g/t Au over 0.61 m; North Hill Zone – 6.34 g/t Au over 0.61 m.

Mineral Record Details

Site Visit Information

Date: Oct 01, 2013

Geologist: Mark Puumala

Notes: A grab sample was collected from an outcrop on the eastern shore of Wire Lake (and adjacent to an abandoned exploration camp). The sampled outcrop exposes sheared, silicified, coarse-grained mafic metavolcanic rock. The outcrop contains gossanous zones that are mineralized with disseminated to blebby sulphides. A grab sample of this material (sample MP-WPT-588 - Thunder Bay South Resident Geologist Office files) assayed >5000 ppb Au. Foliation at the sample location is oriented 350/70. However, foliation in this area appears to show significant variability, with a strike measurement of 320 obtained immediately to the west in a recently exposed (formerly underwater) outcrop. This outcrop is intensely deformed and contains quartz pods, but no significant sulphide mineralization. The variation in foliation orientation may be related to the emplacement of a northwest-striking diabase dike that parallels the trend of the eastern basin of Wire Lake.

References

Book - Exploration report on the Marathon (Hemlo) property, District of Thunder Bay, Ontario.

Publication Number: Date: 1995

Author: Siriunas, J.M.

Publisher Name: Gregor Goldfields

Location: Thunder Bay RGP

MonoMap - Geology of Cirrus Lake-Bamoos Lake area, District of Thunder Bay

Publication Number: R043 Page: 43  Date: 1997

Author: Milne V.G.

Publisher Name: Ontario Dept. of Mines

Location:

Mono - Report of Activities 1996, Resident Geologists

Publication Number: OFR5958 Date: 1997

Author: Newsome J.W., Laderoute D.G.

Publisher Name: Ontario Geological Survey

Location:

Mono - Report of Activities 1995, Resident Geologists

Publication Number: OFR5943 Date: 1996

Author: Baker C.L., Fyon J.A., Laderoute D.G., Newsome J.W.

Publisher Name: Ontario Geological Survey

Location:

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Ministry Contact Information

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