Ontario Mineral Inventory

Ontario Geological Survey
Permanent Link to this Record: MDI42A09SE00013

Record: MDI42A09SE00013

General

Commodities

Primary Commodities: Copper, Zinc, Silver

Secondary Commodities: Cobalt, Gold

Location

Township or Area: Munro, Munro

Latitude: 48° 37' 14.99"    Longitude: -80° 12' 45.07"

UTM Zone: 17    Easting: 558034   Northing: 5385606    UTM Datum: NAD83

Resident Geologist District: Kirkland Lake

NTS Grid: 42A09SE

Point Location Description: shaft and raise

Location Method: AMIS Site Visit

Access Description: Best access to the Potterdoal Mine workings (in the north half of lot 7, concession VI, Munro Township) is via a sand access road which joins the sand and gravel road leading to the Headman Resources Ltd. (serpentine filler) open pit mine, in Warden Township. The Headman Mine access road joins Highway 101 east of Matheson near the eastern boundary of Munro Township.

Exploration History

1926: P. E. Doal: discovers high grade Cu-Zn mineralization; property known as Potter-Doal. 1927-30: Potterdoal Mines Ltd.: acquires 34 claims in Munro Twp.; electrical survey, trenching, 17 DDH's (2,655 ft); 120 ft deep shaft sunk;sank 2 comp. vert. shaft; installed mining plant;1951: sold claims to Munwar Mining Corp., but deal never completed. 1954: R. Potter: holds deposit. 1956-59: New Potterdoal Mines Ltd (formerly Potterdoal Mines Ltd.): 14 DDH's (3,566 ft); chrysotile asbestos fibre (ave. 1/16 in) encountered in 8 ft core length. 1978-81: Amax Minerals Exploration: EM, mag surveys; geological mapping and prospecting; 11 DDH's (1,537 m). 1990: Trenching and sampling by N. McChristie. 1991-1994: Granges Inc. completed ground geophysics and diamond drilling of 24 holes totalling 4769 m., suggests 2 zones of mineralization referred to as the Chert and Potterdoal. 2000: Millstream Mines drilled 1 hole totalling 479 m just west of the Potterdoal on property optioned from M. Dyment and J. Kidston. A 1 m section assayed 1.84% Zn. 2007: Golden Valley Mines Ltd. - DD-10-1982.5 m, assays

Assessment Work on File

Geology

Province: Superior

Subprovince: Abitibi

Terrane: Wawa-Abitibi

Belt: Abitibi

Tectonic Assemblage: Stoughton-Roquemaure

Geological Age: Mesoarchean  

Metamorphism Grade: Greenschist

Geology Comments

Dec 07, 2005 (D Guidon) - Geological units are east-trending and south -facing, consisting of layered grabbroic intrusions, cherty-graphitic sediments, tholeiitic basaltic flows and basaltic komatiitic flows. A series of north-trending diabase dikes crosscut the sequence.

Jan 25, 2016 (R Degagne) - Geological mapping iindicates that bedrock in the area consists mainly of weakly metamorphosed (greenschist or lower metamorphic grade) subaqueously deposited felsic to ultramafic volcanic and intrusive rocks of the (Archean) Stoughton-Roquemaure Group which strike east southeast, dip steeply, face south, and occupy part of the north limb of the southeast striking and northwest plunging McCool Hill Syncline. Narrow (tens of metres in width) north striking diabase dikes of the (Proterozoic) Matachewan swarm intrude Stoughton-Roquemaure Group rocks in the area. Recent geophysical surveys of Munro Township (OGS 1984; assessment files, Resident Geologist's Office, Kirkland Lake) have delineated several anomalous bedrock conductors which coincide with massive sulfide mineralization at the deposit.

Lithology

Lithology Comments

Jan 25, 2016 (R Degagne) - Banded fine to medium grained chalcopyrite-pyrrhotite-sphalerite is reported to occur at the contact between mafic and ultramafic flow units as a discontinuously developed lenticular mass or series of masses which was 24 feet long and 8 feet wide where exposed in outcrop (SMDR 000925) but which pinched out at a depth of 30 feet. The lenticular sulfide mass is reported to have well defined margins and to dip 70 degrees north, in marked contrast to the generally steeply south dipping bedrock volcanic stratigraphy which characterizes the area. This mineralization attitude is consistent with the reported orientation of the inclined shaft (dipping north 80 degrees), which was sunk on the sulfide vein, and with the location of the vertical No.2 shaft, which was collared 115 feet north of the inclined shaft to access the same sulfide body (system) which was exposed to the south and explored by the inclined No.1 shaft. Satterly indicated that a well developed shear (termed by him the Potterdoal Fault) is localized along the flow contact with which the sulfide mineralization is associated, that lenses of actinolitized lava occur within this shear, and that a lamprophyre dike also intrudes the contact. The No.1 inclined shaft is reported to have followed the sulfide lens to a depth of 100 feet. Arndt indicated the sulfide lens to be located at the lower contact of Fred's Flow, a thick layered flow of komatiitic affinity (to the south), near the upper contact of Theo's Flow, a thick layered flow of tholeiitic affinity (to the north).

Mineralization

Mineralization Comments

Jan 25, 2016 (D Guidon) - Based on drill interpretation by Granges, the deposit (Potterdoal Zone) is hosted at the tholeiite/kmoatiite contact. A second horizon of Cu-Zn mineralization (Cherty Zone) is located int he cherty-graphitic sediments stratigraphically below the Potterdoal Zone. Anomalous drill interesections extend over a strike length of about 300 m. Significant assays in Chert zone include: 3.85 m of 0.71% Cu and 0.06 % Co in hole PD-2; 2.04 m of 1.30% Cu 5.99% Zn and 0.39% Co in hole PD-4; 3.98 m of 2.83% Cu, 0.98 % Zn, 49.03 g/t Ag and 0.10% Co in Hole PD-12. In the Potterdoal Zone, significant assays include2.4 m of 0.70% Cu, 3.33% Zn, and 0.05% Co in hole PD-8; and 7.70% Cu, 0.81% ZN 0.79 g/t Au and 0.02% Co in hole PD-9.

Jan 25, 2016 (A Wilson) - In 1929 a 29 ton bulk sample of chalcopyrite-pyrrhotite-sphalerite mineralization averaged 15.22% Cu, 4.15% Zn, 2.7 oz. Ag/ton, 0.045 oz. Au/ton. The bulk sample was presumably collected from the shaft area when it was in development. The sample weighed 663.77 t of sulphide material; which averaged 12 oz. Au, 659 oz. Ag and 13,593 lb. Cu. In 1930 a sample weighing 1735.44 tonnes returned 18,371 lb. Cu and 56.53 oz. Au.

Jan 25, 2016 (R Degagne) - Banded fine to medium grained chalcopyrite-pyrrhotite-sphalerite is reported to occur at the contact between mafic and ultramafic flow units as a discontinuously developed lenticular mass or series of masses which was 24 feet long and 8 feet wide where exposed in outcrop (SMDR 000925) but which pinched out at a depth of 30 feet. Dump samples in a waste dump near the fenced and flooded No.2 shaft observed by the present writer in 1984 consisted of heavily weathered medium to fine grained pyrrhotite-chalcopyrite and serpentinite. Whittaker and Malczak noted the presence of epidote and pyrite at the deposit. Ferguson and Freeman described an occurrence of massive sulfide float (some of which is reported to have averaged 12% of copper) in Beatty Township which probably originated at the Potterdoal deposit and which was transported by man.

Alteration Comments

Dec 07, 2005 (R Degagne) - Information in the Amax Minerals Exploration assessment drill logs indicates that stringer mineralization and associated chloritic alteration consistently occur immediately stratigraphically beneath (north of) sulfidic horizons at the deposit.

Mineral Record Details

Mineral Zones - Size and Shape

Rank: 1       Structure Type: Contact

Site Visit Information

Date: Feb 04, 1997

Geologist: R Degagne

Notes: Visited in 1984 by A. C. Bath (OFR 5735, V.1, p.339).The discontinuous lens and pod like volcanogenic base metal sulfide mineralization which apparently characterizes the Potterdoal mineralization likely resulted from subaqueous sulfide deposition from hydrothermal fluids which may have leached metals from stratigraphically underlying material of tholeiitic basalt bulk composition. The apparent lack of a suitable local heat engine (such as a large cooling intrusive body, as at the Potter Mine may explain why the Potterdoal sulfide mineralization (as now known) appears to offer only limited tonnage potential. Accordingly, further base metal sulfide exploration in the area might be best focused elsewhere within the tholeiitic volcanic rocks of the Stoughton-Roquemaure Group, especially along the same stratigraphic horizon(s) which host the Potterdoal and Potter Mine sulfide bodies and where this (these) horizon(s) is (are) stratigraphically underlain by large comagmatic mafic or mafic-ultramafic intrusive.

References

File - Resident Geologist files KL-3461, KL-3905

Publication Number: Date:

Author:

Publisher Name:

Location: Kirkland Lake RGP office

Map - Quaternary geology of Matheson area, Cochrane District

Publication Number: P2735 Scale: 1:50,000    Date: 1985

Author: Vagners U.J.

Publisher Name: Ontario Geological Survey

Location:

Map - Township of Munro, District of Cochrane, Ontario

Publication Number: M1951-05 Date: 1997

Author: Satterly J., Hogg N.

Publisher Name: Ontario Dept. of Mines

Location:

Map - Geophysical/geochemical series, Matheson-Black River area, Munro Township, airborne electromagnetic survey, total intensity magnetic survey, District of Cochrane

Publication Number: M80586 Scale: 1:20,000    Date: 1984

Author: Questor Surveys Ltd.

Publisher Name: Ontario Geological Survey

Location:

Part - Ben Nevis, Munro, Kamiskotia, and other base metal areas, districts of Cochrane and Timiskaming

Publication Number: ARV37-03.001 Page: 35-41  Date: 1998

Author: Gledhill T.L.

Publisher Name: Ontario Dept. of Mines

Location:

Map - Black River-Matheson Area

Publication Number: OFM0013 Scale: 1:15,840    Date: 1985

Author: Johnstone R.M., Trowell N.F.

Publisher Name:

Location:

Part - Geology of Munro Township

Publication Number: ARV60-08 Page: 42-43  Date: 1997

Author: Satterly J.

Publisher Name: Ontario Dept. of Mines

Location:

Mono - Copper, nickel, lead and zinc deposits of Ontario

Publication Number: MDC012 Page: 126  Date: 1969

Author: Shklanka R.

Publisher Name: Ontario Dept. of Mines

Location:

Folio - Munro Township, District of Cochrane

Publication Number: GDIF361 Date: 1997

Author: Kirkland Lake RGO

Publisher Name: Ontario Geological Survey

Location: Kirkland Lake RGO

Mono - Mineral occurrences, deposits, and mines of the Black River-Matheson area

Publication Number: OFR5735 Page: 336-345  Date: 1990

Author: Bath A.C.

Publisher Name: Ontario Geological Survey

Location:

Article - Precambrian geology of the Black River-Matheson (BRIM) area, District of Cochrane

Publication Number: MP126.056S Date: 1997

Author: Johnstone R.M., Trowell N.F.

Publisher Name: Ontario Geological Survey

Location:

Part - Statistical review of Ontario's mineral industry in 1930

Publication Number: ARV40-01.001 Date: 1997

Author: Rogers W.R., Young A.C.

Publisher Name: Ontario Dept. of Mines

Location:

Article - Mineral deposits investigations in the Black River-Matheson (BRIM) area, District of Cochrane

Publication Number: MP119.053 Date: 1997

Author: Whittaker P.J., Malczak J.

Publisher Name: Ontario Geological Survey

Location:

Article - Quaternary geology and geochemical exploration in the Matheson area

Publication Number: MP140.294 Page: 112-123  Date: 1997

Author: McClenaghan M.B., Lavin O.P., Nichol I., Shaw J.

Publisher Name: Ontario Geological Survey

Location:

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For detailed information regarding this mineral record please contact the Kirkland Lake Resident Geologist District Office