Ontario Mineral Inventory

Ontario Geological Survey
Permanent Link to this Record: MDI52A11SW00006

Record: MDI52A11SW00006

General

Commodities

Primary Commodities: Gold

Secondary Commodities: Silver, Copper

Location

Township or Area: Gorham

Latitude: 48° 32' 15.63"    Longitude: -89° 15' 56.42"

UTM Zone: 16    Easting: 332760   Northing: 5378541.99    UTM Datum: NAD83

Resident Geologist District: Thunder Bay South

NTS Grid: 52A11SE, 52A11SW

Point Location Description: Field visit by J. Scott, trench can be seen in Google Earth

Location Method: Data Compilation

Exploration History

1935: showing was discovered. 1936: Lakehead Gold Mines Ltd. was formed to develop the property, and during the summer and fall of that year an extensive program of surface exploration was carried out, with 2100 m of trenching and 1500 m of trenching completed. 1938: Lakehead conducted surface work and drilled 8 DDH totalling 600 m. 1972: MacLeod-Cockshutt identified scheelite on the property. 1986: Inco conducted line cutting, soil sampling, geological, and IP geophysical surveys and drilled 4 DDH totalling 331 m. 1987: Esso Minerals optioned the property and conducted line cutting, a magnetometer survey, geological mapping, stripping and channel sampling. 1988-89: Noranda Exploration optioned the property and conducted geological mapping. 1990: R.V. Oja conducted a magnetometer survey, sampling, and mapping. 1999: R. Pitkanen and D. Pitkanen conducted gridding, stripping, prospecting, and sampling. 2002-03: M. Luski conducted prospecting and mapping.

Assessment Work on File

Geology

Province: Superior

Subprovince: Wawa

Terrane: Wawa-Abitibi

Belt: Shebandowan

Geological Age: Archean  

Lithology

Lithology Comments

Apr 01, 2021 (Therese Pettigrew) - Gorham Township is underlain by mixed mafic to felsic pyroclastic metavolcanics and Timiskaming-type metasediments of the Shebandowan-Wawa greenstone belt, intruded by several granitic stocks. A prominent E-W trending structural zone occurs near the contact between sediments and mafic to felsic pyroclastics. This zone consists of multiple shears affected by carbonate and sericite alteration which host the gold bearing quartz veins of the Gorham properties. A thick unit of jasper iron formation and chert occurs near the volcanic sedimentary contact, along which grab samples have been obtained with anomalous zinc values up to 2450 ppm (AFRI 52A11SW0004).

Mineralization

Mineralization Comments

Apr 01, 2021 (Therese Pettigrew) - Three well documented gold occurrences are located in the south central portion of Gorham Township. These occurrences lie more or less on strike and are known, from west to east, as the Thunderhead Gold Mines property, the Lakehead Gold Mine property, and the Gorham Gold Mines property. The area has been described by Macdonald (1940) as being underlain by felsic volcanic tuffs, and agglomerates with interrelated andesitic flows. The tuffs are carbonatized and most rock units are sheared. Cherty oxide ironstones occur throughout the succession. At the Lakehead Gold Mines property, mineralization associated with the quartz veins consist of disseminated pyrite, chalcopyrite, and visible gold. The wallrock is pyritized up to 3 feet along one side of the quartz vein. Sampling of the vein, by W.W. Beaton, indicated an average of 0.6 ounce gold per ton over 27 inches for a length of 124 feet. Samples collected by RGP staff returned assays of 0.01-2.04 oz/t Au and trace to 0.2 oz/t Ag (Patterson et al., 1984). Development work has disclosed three main veins and several minor ones. The trend in a general east-west direction parallel to the schistosity of the formations. No. 1 vein (Thunderhead) lies in a sheared zone between andesite and banded tuff and has been opened for a distance of approximately 350 feet. It strikes N. 85 E. to S. 85 E. and dips about 80S. Quartz has been injected in the shear zone, forming one main vein with subsidiary stringers alongside. The injected zone averages less than 4 feet in width. Ankerite is common in the quartz. Metallic mineralization consists of irregularly disseminated pyrite, minor amounts of chalcopyrite, and visible gold. A pyritized zone, ranging in width from 6 inches to 3 feet, lies along the north side of the vein. The pyrite, which is coarse and cubic, is evenly distributed. Sampling results, supplied by W. W. Beaton, show an average of 0.6 ounces in gold over 27 inches for a length of 124 feet. The gold, however, is unevenly distributed along this zone. No. 2 vein (Lakehead Gold Mines) occupies a sheared zone in chloritic and agglomeratic tuff. The shear zone has a maximum width of 9 feet; the vein averages less than one foot in width. The vein strikes east-west, dips 800 S., and has been traced for a length of 500 feet. At its west end it narrows and pinches out; the east end is drift-covered. Cross-faulting has displaced the vein in two places, a distance of 2 feet towards its west end and a distance of 18 feet about 80 feet from its east end. The vein quartz contains ankerite and is irregularly mineralized with pyrite. Visible gold is reported from the vein. The supposed westward extension of No. 2 vein occurs in the central part of mining claim R. 463. It has been traced for a.length of 900 feet and opened for approximately 325 feet. The strike varies from east-west to S. 750 E. The vein consists of an irregular quartz injection averaging less than one foot in width in a sheared acid tuff. Mineralization consists of quartz, ankerite, and disseminated pyrite. Pyrite also occurs in the wall rock close to the vein. Assay values are not known. No. 3 vein (Gorham Gold Mines) is an irregular quartz vein ranging in width from 6 inches to 3 feet. It occupies a shear zone in feldspathic tuff. Ankerite occurs with the quartz, and the quartz is slightly mineralized with pyrite. Visible gold is reported as occurring in the vein over a length of 30 feet (Mcdonald, 1940). A chip sample collected by R.V. Oja in 1990 returned 0.74 oz/t Au (Assessment report 52A11SW0001).

Mineral Record Details

References

Compend - Report of activities, 1983, Regional and Resident Geologists

Publication Number: MP117 Scale:     Date: 1984

Author: Kustra C.R.

Publisher Name: Ontario Geological Survey

Location:

Part - Geology of Gorham Township and vicinity

Publication Number: ARV48-03 Scale:     Date: 1998

Author: Macdonald R.D.

Publisher Name: Ontario Dept. of Mines

Location:

Mono - Gold deposits of Ontario, part 1, districts of Algoma, Cochrane, Kenora, Rainy River, and Thunder Bay

Publication Number: MDC013 Scale:     Date: 1971

Author: Ferguson S.A., Groen H.A., Haynes R.

Publisher Name: Ontario Dept. of Mines and Northern Affairs

Location:

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