Ontario Mineral Inventory

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Permanent Link to this Record: MDI42C13SW00047

Record: MDI42C13SW00047

General

Commodities

Primary Commodities: Gold

Secondary Commodities: Copper

Location

Township or Area: Wabikoba Lake Area

Latitude: 48° 49' 44.06"    Longitude: -85° 46' 47.77"

UTM Zone: 16    Easting: 589543   Northing: 5409154    UTM Datum: NAD83

Resident Geologist District: Thunder Bay South

NTS Grid: 42C13SW

Point Location Description: Trench

Location Method: Data Compilation

Access Description: The Armand Lake gold occurrence is located approximately 33 km south-southeast of Manitouwadge, 650 m north-northeast of the east end of Musher Lake, and 400 m west of the west end of Armand Lake. The Hemlo gold deposit is located approximately 16 km to the southwest. The occurrence is accessible via motor vehicle followed by travel on foot. From Manitouwadge, proceed south along Highway 614 for approximately 40 km to the Twist Lake road. Proceed northeast along the Twist Lake road for approximately 6 km to an unnamed secondary logging road. Proceed south along this unnamed road for approximately 350 m to a skidder trail. Proceed easterly, on foot, along this skidder trail for approximately 1.15 km to the vicinity of the occurrence. Gold-bearing sulphide mineralization is exposed in the northern portion of a 300 m long trench located at the terminus of the skidder trail. The occurrence is situated near station 1+50N on line 5+50E of a grid cut on the property in 1988. When examined in 1991, this grid was in relatively good condition.

Exploration History

1957: Geological mapping; CPR (M. Bartley, T. Page). 1964-1965: Geological mapping; ODM (V.G. Milne). 1978-1979: Lake sediment and water geochemical sampling; GSC and MNR. Samples collected from the vicinity of the occurrence contained slightly anomalous amounts of Cu, Zn, Au and Mo. 1983: Airborne geophysical survey (HLEM, VLF-EM, MAG); Aerodat Ltd. 1984: Line cutting, geological mapping, soil geochemical sampling and a ground geophysical survey (IP); Norman Resources Limited. Geological mapping; OGS (G.M. Siragusa). 1988: Line cutting, stripping, geological mapping, and soil and rock geochemical sampling; Noranda Exploration company Limited. 1991: Stripping, trenching, prospecting and sampling; prospectors B. Fowler and M. Shuman. This work resulted in the discovery of green mica-bearing, pyritic, quartz-eye, sericite schists. Grab samples collected from the Noranda trenches returned assay values of up to 0.093 ounce Au/ton. Reconnaissance till sampling; GSC (I.M. Kettles). Samples collected in the general vicinity of the occurrence were found to contain slightly anomalous amounts of Cu and Zn, but not Au. 1992: Line cutting, geological mapping and lithogeochemical sampling; Newmont Exploration of Canada Limited. 1993: Prospecting, stripping, geological mapping and lithogeochemical sampling; prospectors B. Fowler and M. Shuman and Clark Geological Consulting. Geological mapping and lithogeochemical sampling; OGS (D.B. McKay). 1995: Hemlo Gold Mines carried out mapping and trenching. 1996: Hemlo Gold Mines drilled 9 DDH totalling 2796.4 m

Assessment Work on File

Geology

Province: Superior

Subprovince: Wawa

Terrane: Wawa-Abitibi

Belt: Schreiber-Hemlo

Geological Age: Archean  

Metamorphism Type: Regional

Metamorphism Grade: Amphibolite

Geology Comments

Dec 07, 2005 (D McKay) - The Armand Lake gold occurrence is located in the Wawa subprovince approximately 16 km northeast of the Hemlo mines. The area surrounding the occurrence is underlain primarily by an east-southeasterly-trending sequence of mafic to felsic metavolcanic and lesser metasedimentary rocks which comprise a portion of the the north limb of the Schreiber-Hemlo greenstone belt (Milne 1968, Map 2147; Siragusa 1985, Map P.2738). These rocks are locally strongly foliated (115 degrees/80 degrees SW) and altered (silicified, sericitized, feldspathized and pyritized), and mineral assemblages indicate they have experienced lower amphibolite facies-grade regional metamorphism (Milne 1968; Barry 1983). In the vicinity of the occurrence, the supracrustal sequence is approximately 3.5 km wide and is bounded to the north and south by granodioritic rocks of the Dotted Lake Batholith and the Musher Lake Pluton, respectively (Milne 1968, Map 2147). The northern portion of the belt is dominated by massive to pillowed basalts which are overlain to the south by intermediate to felsic pyroclastic rocks containing minor metasedimentary interbeds (Milne 1968; Klatt 1992). The supracrustal sequence dips steeply to the southwest and has been interpreted to young in the same direction (Milne 1968; Klatt 1992). The occurrence is located near the southern boundary of the belt approximately 500 m north of the contact with the Musher Lake Pluton. Quartz- and feldspar-phyric, green mica-bearing, pyritic, felsic rocks occur locally. The Armand Lake gold occurrence is hosted by one of these felsic units and is exposed within a 300 m long trench. This felsic unit is approximately 25 m wide.

Lithology

Lithology Comments

Dec 07, 2005 (D McKay) - Eveleigh (1993, p.9-10) provided the following comments regarding the lithology, alteration and mineralization present on the property: The felsic pyroclastic unit (or quartz eye sericite schist) is usually strongly foliated with sericite and silica alteration. Trace amounts of fuchsite (chromium mica) alteration can be found in some outcrops. The pyrite content usually ranges from 1% to trace. This pyroclastic unit has taken the majority of the structural strain on the property as well as the silicification, probably from the intrusion of the Musher Lake pluton. This is a key unit to focus on for further exploration of the alteration and mineralization. Schnieders and Smyk (1994) provide the following comments: Although protolith determination is difficult because of deformation and alteration, it appears as though fragmental felsic rocks may be pyroclastic, while more massive, quartz-phyric units could either be flows or intrusions. These rocks are commonly altered to a quartz eye-bearing, sericite schist in the vicinity of sulphide mineralization. Outcrops of green mica-bearing, locally pyritic, quartz- and feldspar-phyric sericite schists were located in two separate areas on the Armand Lake property. These rocks are exposed approximately 850 m to the southeast and 600 m to the west, respectively, of the trench containing the Armand Lake gold occurrence. Similar rocks outcrop intermittently between these locations and on an adjacent claims to the west. Collectively, these rocks comprise a single southeasterly-trending unit up to 200 m wide and 6 km long. This unit may represent a flattened and strongly altered (sericitized, albitized and pyritized) apophysis of a larger felsic intrusive body, perhaps the Musher Lake Pluton, and represents an excellent target for Hemlo-style gold mineralization. Preliminary sampling of this unit has returned negligible gold values.

Mineralization

Mineralization Comments

Dec 07, 2005 (D McKay) - Grab samples of pyritic, quartz-rich, possibly silicified, sericite schist (felsic ash tuff?) collected from the occurrence by prospectors B. Fowler and M. Shuman and submitted to the MNDM for analysis have returned assay values of up to 0.093 ounce Au per ton and 2280 ppm Cu. Grab samples of rusty-weathering, banded light and dark gray, moderately foliated, medium-grained, sericite-quartz-feldspar schist containing 2 to 3% fine- to medium-grained pyrite locallized in poorly-defined, foliation parallel bands collected from the occurrence by D. McKay for the OGS returned assay values of up to 0.004 ounce Au per ton and 504 ppm Cu.

Mar 14, 2019 (Therese Pettigrew) - Hemlo Gold DDH F1-95-2 assayed 37.351 ppm Au over 1.0 m. Hemlo Gold DDH F1-95-4 assayed up to 28.895 ppm Au (3.945 ppm Au over 3.0 m; Assessment file 42C13SE0070).

Alteration Comments

Dec 07, 2005 (D McKay) - The felsic unit hosting the occurrence is locally altered to sericite schist that contains green mica. Green mica-bearing rocks have been noted over a strike length of at least 3.5 km and are most extensively developed at the northwestern end of the property. Recent logging activity has revealed outcrops of massive to foliated, quartz- and quartz-feldspar-phyric rocks with thin seams and lenses of green mica. Locally, green mica may comprise up to 40% of the rock. The felsic rocks are also variably mineralized with pyrite and sericite. Although chemical analyses have not been conducted on this green mica, its colour, habit and mode of occurrence are remarkably similar to that of the vanadium- and chromium-bearing muscovite that is a key component of the alteration mineral assemblage at Hemlo.

Mineral Record Details

References

Mono - Mineral Occurrences in the Manitouwadge Area, Volumes 1, 2 and 3

Publication Number: OFR5906 Date: 1994

Author: McKay D.B.

Publisher Name: Ontario Geological Survey

Location:

Map - Black River area, southeast part, District of Thunder Bay

Publication Number: P0335 Scale: 1:31,680    Date: 1997

Author: Milne V.G.

Publisher Name: Ontario Dept. of Mines

Location:

File - Schreiber-Hemlo Resident Geologist Mineral Deposit Files

Publication Number: Min Dep Date:

Author:

Publisher Name:

Location: Thunder Bay RGP

Map - White Lake sheet, Thunder Bay District

Publication Number: M2147 Scale: 1:31,680    Date: 1968

Author: Milne V.G.

Publisher Name: Ontario Dept. of Mines

Location:

MonoMap - Geology of the Black River area, District of Thunder Bay

Publication Number: R072 Date: 1968

Author: Milne V.G.

Publisher Name: Ontario Dept. of Mines

Location:

Map - Geological series, Precambrian geology, Lumby Lake area, western part, Kenora District

Publication Number: P2828 Scale: 1:15,840    Date: 1985

Author: Jackson M.C., Chevalier P.

Publisher Name: Ontario Geological Survey

Location:

Article - Schreiber-Hemlo Resident Geologist's District-1991

Publication Number: MP158.007 Page: 121-163  Date: 1997

Author: Schnieders B.R., Smyk M.C., McKay D.B.

Publisher Name: Ontario Geological Survey

Location:

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