Ontario Mineral Inventory

Ontario Geological Survey
Permanent Link to this Record: MDI42A09SE00009

Record: MDI42A09SE00009

General

Commodities

Primary Commodities: Gold

Location

Township or Area: Munro

Latitude: 48° 33' 4.22"    Longitude: -80° 13' 43.54"

UTM Zone: 17    Easting: 556915.197   Northing: 5377850.722    UTM Datum: NAD83

Resident Geologist District: Kirkland Lake

NTS Grid: 42A09SE

Point Location Description: A point 1.40 km north and 3.60 km east of the southwest corner of Munro Township.

Location Method: Conversion from MDI

Access Description: A badly overgrown road (the location of which is shown by Satterly (1952)) may be followed on foot to the outcrop area in the north half of lot 8, concession I, Munro Township. The overgrown road joins the Croesus (gold) Mine access road a few hundred metres northeast of the Croesus shaft and may be reached using a 4 wheel drive vehicle or ATV from the south via the Croesus Mine road from Highway 101. Alternatively, the overgrown road may be reached by 2 wheel drive vehicle via the Croesus Mine road from the north where it joins gravel and dirt roads near the now flooded Canadian Johns-Manville Co. Ltd. Munro (asbestos) Mine open pit. The Munro Mine site may be reached via a paved road which joins Highway 101 near the southwest corner of Munro Township.

Exploration History

1946: Walhart Gold Mines Ltd. diamond drilled 10 holes totalling 1,988 feet which were targeted on quartz- carbonate veins which had been pitted and trenched on patented claim 1671. Hole No.5 intersected 10 feet of auriferous material averaging 0.39 ounce of gold per ton in what was described as pyritic silicified porphyry hosting quartz-carbonate stringers. Hole numbers 1, 2, 3, 4, and 9 also returned gold assays ranging from 0.01- 0.02 ounce of gold per ton across 4 to 5 foot assay lengths of porphyry. 1951: Walhart Gold Mines held patented claims 1671, 4359, and 5381 in the north half of lot 8, concession I, Munro Township (Satterly 1952). 1962: Walhart Gold Mines Ltd. had its charter cancelled in September (Canadian Mines Register 1966). 1963: The patented claims formerly held by Walhart Gold Mines were restaked by Canadian Johns-Manville Co. Ltd. 1964: Magnetic and HL electromagnetic surveys were completed on Canadian Johns-Manville ground. 1966: Canadian Johns-Manville diamond drilled one vertical 503.3 foot hole a few hundred metres east of the occurrence, in the northeast quarter of the north half of lot 7, concession I, Munro Township. 1981: Amax Minerals Exploration diamond drilled 4 holes totalling 153.7 m under a joint venture agreement with Canadian Johns-Manville. Although records of this drilling are not present in the assessment files, both the drill logs and core (without assay results) are currently (1988) available for viewing at the Ontario Ministry of Northern Development and Mines Core Storage Library, in Swastika. Grid coordinates for the drill holes are provided with the logs, probably indicating that ground geophysical surveys were completed prior to the diamond drilling, but no records of such surveys are available to the present writer.

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 (R Degagne) - Bedrock in the occurrence area occupies part of the south limb of the southeast striking and northwest plunging McCool Hill Syncline (Johnstone 1987). A few hundred metres north of the occurrence, an extensive swamp coincides with thelocation of the southeast striking Munro Fault Zone (Johnstone 1987, Satterly 1952). A recent geophysical survey (OGS 1984) indicates that the occurrence coincides with electromagnetic bedrock conductor anomalies which were detected across 5 contiguous flight lines. The occurrence is shown by the same survey to be associated with a small magnetic depression within a prominent, regional scale, southeast striking magnetic high which is immediately south of a prominent magnetic low which coincides with the trace of the Munro Fault zone.

Lithology

Lithology Comments

Dec 07, 2005 (R Degagne) - Bedrock underlying the north half of lot 8, concession I, Munro Township is well exposed and consists mainly of variably carbonatized, steeply dipping, southeast striking, and north facing weakly metamorphosed (greenschist or lower metamorphic facies) subaqueously deposited tholeiitic basalt and intercalated komatiitic flow and related rocks of the (Archean) Stoughton-Roquemaure Group (Johnstone and Trowell 1985, 1984; Jensen and Baker 1986; Johnstone 1987; Johnstone and Steele 1989). Intrusive rocks in the area include mafic to ultramafic sill-like bodies within the Munro Fault zone and narrow (tens of metres in width) north striking diabase dikes of the (Proterozoic) Matachewan swarm. These dikes are exposed about 1.5 km west and about 1.5 km northeast of the occurrence (Johnstone 1987, Satterly 1952, Heaman 1989). Numerous pits and trenches, many of which are now overgrown and/or detritus filled, have been blasted into and/or expose southeast striking, steeply dipping and north facing mafic to ultramafic flow and related rocks. Some flows are pillowed, flow breccia horizons may occur locally, and some lavas are variolitic. The volcanic rocks are variably carbonatized. Satterly (1952) indicated that a 40 foot wide zone of carbonatization striking about 060 transects the volcanic stratigraphy in the northwest central occurrence area. Volcanic rocks immediately north of the overgrown road which leads to the occurrence from the west are not carbonatized except locally, where quartz-dolomite-albite veinlets hosted within pervasively (but locally) dolomitized volcanic rocks occur sporadically. Distally and south of the zone of carbonatization mapped by Satterly, carbonatization is manifested in the volcanic rocks as weak but penetrative rusty weathering calcite and Fe-dolomite alteration.

Mineralization

Mineralization Comments

Dec 07, 2005 (R Degagne) - Volcanic rocks immediately north of the overgrown road which leads to the occurrence from the west are not carbonatized except locally, where quartz-dolomite-albite veinlets hosted within pervasively (but locally) dolomitized volcanic rocks occur sporadically. Distally and south of the zone of carbonatization mapped by Satterly, carbonatization is manifested in the volcanic rocks as weak but penetrative rusty weathering calcite and Fe-dolomite alteration. Exposed in the trenches, pits, and in rock waste piles marginal to them are white to greasy grey quartz-Fe-dolomite-(albite) veinlets which are rarely wider than 6 cm. These are hosted by recrystallized dolomite. The highest gold assays were obtained from samples consisting of quartz-Fe-dolomite-(albite) veinlets hosted by pyritic dolomite. Analyses*: Sample AB-87-69: 10 Au ppb, nil Ag ppm, 44 Cu ppm, 23 Pb ppm, 11 Zn ppm, 7 As ppm, <10 Mo ppm. Sample AB-87-70: 23 Au ppb, nil Ag ppm, 152 Cu ppm, 46 Pb ppm, 58 Zn ppm, 5 As ppm, <10 Mo ppm. Sample AB-87-73: 134 Au ppb, tr Ag ppm, 225 Cu ppm, 46 Pb ppm, 55 Zn ppm, 4 As ppm, <10 Mo ppm. Sample AB-87-74: 1944 Au ppb, tr Ag ppm, 117 Cu ppm, 26 Pb ppm, 17 Zn ppm, 9 As ppm, <10 Mo ppm. Sample AB-87-75: 3178 Au ppb, 0.7 Ag ppm, 117 Cu ppm, 23 Pb ppm, 26 Zn ppm, 8 As ppm, <10 Mo ppm. Sample AB-87-76: 230 Au ppb, tr Ag ppm, 244 Cu ppm, 47 Pb ppm, 30 Zn ppm, 6 As ppm, <10 Mo ppm. Sample AB-87-77: 545 Au ppb, tr Ag ppm, 129 Cu ppm, 53 Pb ppm, 88 Zn ppm, 6 As ppm, <10 Mo ppm. * All analyses except those for arsenic performed by Timiskaming Testing Laboratory, Cobalt. Arsenic analyses were by Swastika Laboratories, Swastika.

Alteration Comments

Dec 07, 2005 (R Degagne) - Volcanic rocks immediately north of the overgrown road which leads to the occurrence from the west are not carbonatized except locally, where quartz-dolomite-albite veinlets hosted within pervasively (but locally) dolomitized volcanic rocks occur sporadically. Distally and south of the zone of carbonatization mapped by Satterly, carbonatization is manifested in the volcanic rocks as weak but penetrative rusty weathering calcite and Fe-dolomite alteration.

Mineral Record Details

Mineral Zones - Size and Shape

Rank: 1       Structure Type: Shear

Site Visit Information

Date: Feb 05, 1997

Geologist: R Degagne

Notes: Visited in 1987 by A. C. Bath (OFR 5735, V.1, 1990). Future exploration work in the area, if undertaken, should consider the possibility that the carbonate zones (which are potentially host to auriferous quartz-carbonate stringer mineralization) within the Stoughton-Roquemaure Group may occur as conformable horizons. At the Walhart occurrence, at least one component of the stringer system may be oriented subparallel to local stratigraphy. Accordingly, optimum drilling orientation for this stringer set may be orthogonal to local stratigraphy. Near the old Walhart Gold Mines claims, this would be at about azimuth 200. In contrast to auriferous quartz-carbonate stringer systems elsewhere near the Munro Fault Zone, at the Walhart occurrence arsenopyrite is conspicuous by its absence. This is reflected in the uniformly low arsenic assays obtained by the present writer. Silver, lead, zinc and molybdenum assays were likewise consistently low. Copper assays were on average elevated, while all samples assayed except two contained anomalously elevated gold values. The highest gold assays were obtained from samples consisting of quartz-Fe-dolomite-(albite) veinlets hosted by pyritic dolomite. It should be noted that Kidd Creek Mines performed 4 whole rock major oxide and trace element (Rb, Sr, Y, Zr) analyses on samples from the Amax drill core stored in the Ontario Ministry of Northern Development and Mines Core Storage Library in Swastika. The results of these analyses are available at the Core Storage Library in Swastika.

References

Map - Black River-Matheson Area

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

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

Publisher Name:

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:

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:

Part - Geology of Munro Township

Publication Number: ARV60-08 Page: 52  Date: 1997

Author: Satterly J.

Publisher Name: Ontario Dept. of Mines

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:

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

Publication Number: MDC013 Page: 134  Date: 1971

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

Publisher Name: Ontario Dept. of Mines and Northern Affairs

Location:

Mono - Preliminary report on the Timmins-Kirkland Lake area, gold deposits file

Publication Number: OFR5467 Page: G0003  Date: 1983

Author: Hodgson C.J.

Publisher Name: Ontario Geological Survey

Location:

Folio - Munro Township, District of Cochrane

Publication Number: GDIF361 Date: 1997

Author: Kirkland Lake RGO

Publisher Name: Ontario Geological Survey

Location:

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

Publication Number: OFR5735 Page: 357-365  Date: 1990

Author: Bath A.C.

Publisher Name: Ontario Geological Survey

Location:

Article - Quaternary geology and geochemical exploration in the Matheson area

Publication Number: MP140.294 Date: 1997

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

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:

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