Ontario Mineral Inventory

Ontario Geological Survey
Permanent Link to this Record: MDI52O06NW00003

Record: MDI52O06NW00003

General

Commodities

Primary Commodities: Gold

Location

Township or Area: Meen Lake Area

Latitude: 51° 25' 17.08"    Longitude: -91° 18' 16.43"

UTM Zone: 15    Easting: 617883.44   Northing: 5698052.87    UTM Datum: NAD83

Resident Geologist District: Thunder Bay North

NTS Grid: 52O06NW

Point Location Description: Diamond drill holes

Location Method: Conversion from MDI

Access Description: The Umex-Dorothy Lake deposit is located about 76 km west of Pickle Lake and 4.6 km north-northeast of Dorothy Lake. The Umex-Dorothy Lake deposit is best accessed by helicopter to one of the nearby small, un-named lakes. These lakes are believed to be marginal for float- and ski-equipped aircraft.

Exploration History

1973: Umex Corporation Ltd. drilled a diamond-drill hole on this deposit as part of a large follow-up program to a regional airborne geophysical survey. The core was not assayed for gold at this time. 1985: Umex Inc. re-logged the 1973 drill core and sampled for gold, base metals and major oxides. Umex Inc. also did ground soil and lithogeochemistry in 1985. 1986: Geocanex Ltd., St. Joe Canada Inc. and Kerr Addison Mines Ltd. commissioned separate airborne mag and EM surveys which included the area of the Umex-Dorothy Lake deposit. 1986: Umex Inc. did geological mapping, ground mag and EM surveys and 5 diamond-drill holes, totalling 626 m. 1987: Umex Inc. reported drilling 1 diamond-drill hole, 255.7 m in length, on the deposit. 1988: Umex Inc. reported drilling 27 diamond-drill holes, totalling 3763.44 m, on the deposit. 1990: Major General Resources Inc. drilled 7 DDH totalling 2063.9 m. 1994: Commander Resources Ltd. conducted an HEM survey. 1997: Major General Resources conducted a ground magnetometer survey. 1998: Major General Resources conducted an IP survey. 2006: Canadian Golden Dragon Resources Ltd. conducted prospecting and airborne magnetic and VLF-EM surveys. 2007: Canadian Golden Dragon collected historical core samples and located historical drill collars. Canadian Golden Dragon changed its name to Trillium North Minerals Ltd. 2009: Manicouagan Minerals Inc. optioned the property from Trillium North Minerals Ltd. and drilled 16 DDH totalling 2296 m (7 DDH on the Dorothy Main Zone). 2014: Manicouagan Minerals and Flemish Gold merged to form Murchison Minerals. 2020: Ardiden acquired the property. 2023: Ardiden drilled 30 DDH totalling 3845 m.

Assessment Work on File

Geology

Province: Superior

Subprovince: Uchi

Terrane: North Caribou

Domain: Uchi

Belt: Meen-Dempster

Geological Age: Archean  

Geology Comments

Dec 07, 2005 (B Nelson) - The Umex-Dorothy Lake deposit consists of 2 zones. The main zone is hosted in a diorite intrusive. The West Zone is hosted by mafic metavolcanics. The diorite sill which is host to the Main Zone is 90 to 150 m in width and intrudes a succession of intermediate pyroclastics at the contact with a unit of chemical metasediments. A shear zone and coincident 30 m to 50 m wide alteration zone trends 135 degrees to 140 degrees along the southern contact of the sill. In the alteration zone, hydrothermal activity affected the amphiboles in the diorite and resulted in a fine-grained alteration assemblage of magnetite, biotite, sericite, carbonate, chlorite, epidote and quartz. Auriferous zones within the alteration zone are characterized by intense, pervasive silicification/silica flooding, quartz veining and sulphidization. The dominant sulphide is pyrite in concentrations up to 10%. There are local concentrations of pyrrhotite and traces of chalcopyrite. The chemical metasediment south of the diorite is 5 cm to 30 cm wide and is composed primarily of chert with seams of pyrite, pyrrhotite and magnetite. Locally, quartz veining from the altered diorite cut into the chemical metasediment unit. When assayed, the chemical metasediment cut by quartz veins reports values up to 0.40 oz/ton Au over 1.5 m. South of the chemical metasedimentary unit, the rock succession passes into mafic metavolcanics. The West Zone occurs along the same shear zone which hosts the main zone. The West Zone is hosted in mafic metavolcanics and shearing and alteration is evident over 1.7 m to 4.5 m widths in drill core. The auriferous zone is characterized by pervasive carbonatization, biotite replacement of other ferromagnesian minerals and quartz veining. Pyrite (3%-5%) and magnetite occur in the auriferous zone.

Lithology

Lithology Comments

Dec 07, 2005 (B Nelson) - The Umex-Dorothy Lake deposit consists of 2 zones. The main zone is hosted in a diorite intrusive. The West Zone is hosted by mafic metavolcanics. The diorite sill which is host to the Main Zone is 90 to 150 m in width and intrudes a succession of intermediate pyroclastics at the contact with a unit of chemical metasediments. A shear zone and coincident 30 m to 50 m wide alteration zone trends 135 degrees to 140 degrees along the southern contact of the sill. In the alteration zone, hydrothermal activity affected the amphiboles in the diorite and resulted in a fine-grained alteration assemblage of magnetite, biotite, sericite, carbonate, chlorite, epidote and quartz. Auriferous zones within the alteration zone are characterized by intense, pervasive silicification/silica flooding, quartz veining and sulphidization. The chemical metasediment south of the diorite is 5 cm to 30 cm wide and is composed primarily of chert with seams of pyrite, pyrrhotite and magnetite. The West Zone is hosted in mafic metavolcanics and shearing and alteration is evident over 1.7 m to 4.5 m widths in drill core.

Mineralization

Mineralization Comments

Dec 07, 2005 (B Nelson) - The best assay interval from the West Zone averaged 0.14 oz/ton Au over 2.9 m. The best assay value reported from the chemical metasedimentary unit was 0.40 oz/ton Au over 1.5 m. Reserves have been calculated as 236220 t, with an average grade of 6.17 g/t Au (0.18 oz/ton) (The Northern Miner, June 11, 1990, p.13).

May 19, 2016 (Therese Pettigrew) - The Dorothy Main Zone consists of a zone of quartz-tourmaline veining hosted by an altered and deformed diorite that has been traced by previous operators over a length of 700 metres and remains open at depth and along strike. Six of the seven holes drilled in 2009 by Manicouagan on the Dorothy Main Zone encountered a 2-4 metre wide (true width) zone, at a depth of 50-100 metres, of greater than 20% quartz-tourmaline veining within a sheared metadiorite (2-5% pyrite). This mineralization occurs within a broader zone (20-30 metres) of altered diorite (1-2% pyrite) containing about 5% quartz tourmaline veins and stockworks. Assay results included 1.8 metres of 5.15 gpt gold from hole DOR-09-05, 7.49 g/t Au over 1 m from DOR-09-06, and 2.88 g/t Au over 3 m from DOR-09-01 (AFRI 20000005981). A spectacular gold assay from the Main Zone of 472.8 g/t Au over 0.5 m, is from a narrow protomylonite zone in diorite, cut by a 1 cm wide quartz vein with a large mass of visible gold in DDH Dor-90-43. Most assays recorded average 6 g/t Au. The best assay interval from the West Zone averaged 4.35 g/t Au over 2.9 m. The best assay value reported from the chemical sedimentary unit was 0.40 oz/ton Au over 1.5 m (Harron, 2009).

Mineral Record Details

References

MonoMap - Geology of the Cat Lake-Pickle Lake area, districts of Kenora and Thunder Bay

Publication Number: R207 Date: 1982

Author: Sage R.P., Breaks F.W.

Publisher Name: Ontario Geological Survey

Location:

Mono - Mineral Deposits of the Central Portion of Uchi Subprovince, Volume 1, Meen Lake to Kesagiminnis Lake Portion

Publication Number: OFR5869 Page: 258  Date: 1993

Author: Seim G.Wm.

Publisher Name: Ontario Geological Survey

Location:

Map - Geological series, Precambrian geology, Meen Lake area, eastern part, Kenora District (Patricia Portion)

Publication Number: P2620 Scale: 1:15,840    Date: 1983

Author: Stott G.M., LaRocque C.

Publisher Name: Ontario Geological Survey

Location:

Map - Cat Lake-Pickle Lake, geological compilation series, Kenora and Thunder Bay districts

Publication Number: M2218 Scale: 1:253,440    Date: 1976

Author: Sage R.P., Breaks F.W., Troup W.R.

Publisher Name: Ontario Division of Mines

Location:

Publication - Technical Report on Three Gold Exploration Properties; Pickle Lake Area, Ontario, Canada

Publication Number: 2009 NI 43-101 Date: 2009

Author: Harron, G.A.

Publisher Name: Manicouagan Minerals Inc.

Location: SEDAR

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