Ontario Mineral Inventory

Ontario Geological Survey
Permanent Link to this Record: MDI42L04NE00014

Record: MDI42L04NE00014

General

Commodities

Primary Commodities: Gold

Location

Township or Area: Oboshkegan

Latitude: 50° 9' 54.06"    Longitude: -87° 33' 54.28"

UTM Zone: 16    Easting: 459641.52   Northing: 5557131.06    UTM Datum: NAD83

Resident Geologist District: Thunder Bay North

NTS Grid: 42L04NE

Point Location Description: Precise

Location Method: Data Compilation

Access Description: The Knucklethumb Lake property is located 53 km north of Jellicoe and approx. 72km northeast of the town of Geraldton. A logging road that extends north for 100km from the Trans-Canada Highway 11 comes within 1 km of the property.

Exploration History

1915: Albert Kipper discovered gold south of Hull Lake and west of Knucklethumb Lake. 1976: NWT Copper Mines Ltd. drilled 1 hole. Hollinger Argus Ltd. electromagnetic survey south of area. 1980-81: Hollinger Argus Ltd. carried out a mag survey and drilled 6 DDH totalling 443.2 m. 1984: Geological, Lithoogeochemical, VLF-EM and MAG surveys by S.N. Roach. 1987: Humus sampling, IP, ground electromagnetic surveys done by Noranda under option from S.N. Roach. 1996: Mapping by G. Stott and J. Parker (OGS). 1996: Cameco acquires area by option from NWT Copper Mines Ltd. and by staking. 1997-99: Cameco Gold Inc. carried out line cutting, ground magnetic and IP/resistivity surveys, geological mapping, trenching and drilled 4 DDH totalling 1195 m.

Assessment Work on File

Geology

Province: Superior

Subprovince: Wabigoon

Terrane: Eastern Wabigoon

Belt: Onaman-Tashota

Geological Age: Archean  

Geology Comments

Dec 07, 2005 (Q Unknown) - The property is located in the north-central portion of the Onaman-Tashota metavolcanic belt. Specifically, the property occurs within the Metcalfe Lake Metavolcanic belt. Amukun (1977) mapped the area east of Metcalfe Lake as being underlain by mafic to felsic metavolcanic rocks. Felsic metavolcanic rocks consist of rhyolite, rhyodacite, rhyolite porphyry, pyroclastic breccia and sericite schist. Mafic metavolcanic rocks consist of massive to pillowed basalt, and are foliated to strongly sheared. South and east of Knucklethumb Lake is a metasedimentary unit composed of slate, greywacke and conglomerate. Horebelned-quartz monzonite and gabbro intrude these metasedimentary rocks. Coarse-grained 'golfball' anorthosite and gabbroic rocs intrude the mafic metavolcanic rocks east of Hull Lake.

Lithology

Lithology Comments

Dec 07, 2005 (Q Unknown) - The Knucklethumb Lake property is located in an extensive felsic sequence that is 26 square km. The property consists of 94% felsic to intermediate metavolcanics, 5% mafic metavolcanics, and 1% metasedimentary rocks. Thin lamprophyre dikes cross-cut the metavolcanics. A small granitic intrusion lies to the south of the property.

Mineralization

Mineralization Comments

Oct 30, 2018 (Therese Pettigrew) - The Big Bear showing (located at NAD83 UTM Zone 16 458925 m E, 5557514 m N) assayed 16 gpt Au from a grab sample. The Jaz showing assayed 3.1 gpt Au over 1.5 m. The Claim Line showing (located at NAD83 UTM Zone 16 460271 m E, 5557106 m N) assayed 145.2 gpt Au over 0.3 m. There are 4 styles of gold mineralization on the property: 1) auriferous hypabyssal intrusions porphyries/felsites) emplaced within intermediate to felsic fragmental volcanics, e.g., Hourglass and Ryne showings; 2) gold within highly altered (silicified/feldspathized, carbonatized, sulphidized) deformation zones, e.g., Ryne and Cabin showings; 3) gold within pyrite chalcopyrite pyrrhotite-bearing quartz-iron carbonate veins, e.g., Big Bear, MVP and Green Jimmy showings; and 4) free gold within quartz-tourmaline veins, felsite dykes and along shear/foliation planes, e.g., Claimline, Hourglass and Ryne showings. DDH OB-2-2-80 assayed up to 1.03 gpt Au over 1.52 m. DDH OB-2-3-80 assayed up to 4.8 gpt Au over 0.6 m. DDH ONA99-32 assayed up to 0.55 gpt Au over 3.0 m (AFRI 42L03NW2006).

Dec 07, 2005 (Q Unknown) - The Gold occurrences extend over a strike length of 1600m, but the width is very limited. Both sulphides and quartz veining are present within felsic volcanic rocks, but the mineralization is confined to narrow, tight shear zones. The largest occurrence on the property is the RYNE showing.

Alteration Comments

Dec 07, 2005 (Q Unknown) - Alteration is mainly due to strong shearing and fracturing. Altered rocks contain disseminated pyrite and arsenopyrte.

Mineral Record Details

Mineral Zones - Size and Shape

Site Visit Information

Date: Sep 16, 1999

Geologist: Q Unknown

Notes: MVP: occurs in mafic volcanics. The basalts are veined with calcite and are cut by narrow qtz. veins containing vuggy pyrite. The volcanics are moderately sheared. The qtz vein contains 5% pyrite and trace chalcopyrite. RYNE: consists of qtz veinlets and stringers hosted by a carbonatized felsic volcanic flow (tuff?). A 1cm carbonate rind is very evident when the rock is broken. The felsic volcanic contains 3-4% very fine grained pyrite. Minor qtz veining was observed in an outcrop at 17+35E on the baseline. No arsenopyrite was located at this showing. CLAIM LINE: hosted by felsic rocks (prob. tuffs). The area is characterized by intense sericitic alteration and moderate to strong shearing across a 5m width. A long trench has been blasted which measures 5m long by 3m wide by 2m deep. Sheared felsic volcanics with minor qtz veining is exposed along the trench wall. Stretched felsi blebby pyrite occurs in the felsic volcanic (up to 3%). Tourmaline was noted in qtz veins near a drill site just to the west of the pit. JAZ: is hosted by felsic to intermediate tuffaceous rocks. A very narrow shear zone crosses the outcrop and this zone contains narrow qtz veinlets and minor sulphides. The sulphides are primarily concentrated in the centre of the outcrop in a small pod with limited strike extent.

References

Book - NMINER HIST FILE T.BAY

Publication Number: NMINER Scale:     Date: 1996

Author:

Publisher Name:

Location:

Map - Tashota, Thunder Bay District

Publication Number: M2354 Scale: 1:31,680    Date: 1976

Author: Amukun S.E.

Publisher Name: Ontario Division of Mines

Location:

MonoMap - Geology of the Tashota area, District of Thunder Bay

Publication Number: R167 Scale:     Date: 1977

Author: Amukun S.E.

Publisher Name: Ontario Geological Survey

Location:

Part - Tashota-Onaman gold area (District of Thunder Bay)

Publication Number: ARV34-06.003 Scale:     Date: 1998

Author: Gledhill T.L.

Publisher Name: Ontario Dept. of Mines

Location:

Book - GEOLOGICAL COMPILATION OF KNUCKLETHUMB LAKE PROPERTY

Publication Number: MIN DEP Scale:     Date: 1994

Author: Roach, S.N.

Publisher Name:

Location: 42L04NE MINERAL DEPOSIT FILE

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