Ontario Geological Survey
Permanent Link to this Record: MDI52O11SW00004
|Record Name(s)||Chellow Vein / Cliff Zone - 1950, McVicar Lake E, 7 - 1979, McVicar Lake South - 1950|
|Related Record Type||Simple|
|Date Last Modified||2022-Mar-02|
Primary Commodities: Gold
Secondary Commodities: Copper
Township or Area: McVicar Lake Area
Latitude: 51° 32' 19.3" Longitude: -91° 27' 5.49"
UTM Zone: 15 Easting: 607390 Northing: 5710869 UTM Datum: NAD83
Resident Geologist District: Thunder Bay North
NTS Grid: 52O11SW
Point Location Description: General
Location Method: Conversion from MDI
1950: Chellow Gold Mines Ltd. conducted geological mapping, trenching and diamond drilling in the Lower McVicar Lake area. 1959-1961: Kenlew Mines Ltd conducted geological mapping, stripping, trenching and diamond drilling in the lower McVicar Lake area and the area to the east of McVicar Lake. 1968-1969: New Jersey Zinc Exploration Company (Canada) Limited conducted geological mapping, geophysics, trenching and limited diamond drilling for VMS mineralization in the area north of north of McVicar Lake. 1971: Hoey Syndicate conducted geological mapping, trenching and geophysics for Cu-Ni-PGE mineralization in the lower half of the McVicar Lake area. 1977-1981, 1987, 1991: Cominco Ltd conducted extensive airborne geophysical surveys as well as diamond drilling over the McVicar Lake and Andy lake areas, well as limited diamond drilling in McVicar and Cannon Lake areas for gold and base metals. 1985-1994: Utah Mines, later BHP-Utah Mines, and then simply BHP conducted extensive grid mapping, geophysics and diamond drilling on the area (including 6 DDH totalling 802.8 m on the Chellow Vein) surrounding McVicar Lake. Utah Mines also conducted extensive work in the western Lang Lake area. 1988: Bayaura Mines Ltd. carried out magnetometer, gradiometer, and VLF-EM surveys. 2001-2003: Prospector Consolidated Resources Inc and Continuum Resources Ltd, conducted extensive trenching and limited diamond drilling for gold on the old BHP-Utah Mines property in the McVicar Lake area. 2010: Wildcat Exploration Ltd. staked the property. 2011: Wildcat Exploration flew an airborne magnetic and radiometric survey and conducted prospecting, mapping, rock and soil sampling. 2012: Wildcat Exploration carried out channel sampling and mapping.
|Office File Number||Online Assessment File Identifier||Online Assessment File Directory|
Terrane: North Caribou
Belt: Lang Lake
Geological Age: Neoarchean
Mar 28, 2007 (Mark Puumala) - Stott and Corfu (1991) describe the Lang Lake greenstone belt as being dominated by tholeiitic basalt flows and calc-alkalic pyroclastic deposits, with the eastern portion of the belt containing a significant clastic metasedimentary sequence that also includes iron formation horizons. The supracrustal rocks of this belt have been provisionally assigned to the Confederation Assemblage by Stott and Corfu (1991) based on a single age determination from a dacitic tuff in the lowermost (i.e., interpreted to be oldest) portion of the supracrustal rock sequence. The entire belt has been isoclinally folded into an east-trending and east-plunging syncline (Thomas 1988). Thomas (1988) also indicates that the belt contains two significant intrusions, including an east-west trending mafic stock in the Sor-McVicar Lakes area, and a later north-south trending felsic intrusion in the Shonia-McVicar Lakes area. The mafic intrusion has a number of Cu-Ni-PGE occurrences that have been documented near its northern contact, while the felsic intrusion hosts several gold occurrences. The dominant structural feature in the area is the Bear Head Fault Zone, which is located immediately to the southwest. This is an approximately northwest-southeast striking, regional-scale, dextral shear zone that has been classified by Stott and Corfu (1991) as a transcrustal megafault. This fault zone extends approximately 515 km from Lake Winnipeg to the northern boundary of the Meen-Dempster Greenstone Belt (Osmani and Stott 1988). Two additional WNW-ESE trending deformation zones referred to as the Lower McVicar Fault and Altered Zone Fault (McKay 2004) are also present in the area and are associated with a number of gold occurrences. Fumerton (1997) suggests a relationship between the Altered Zone Fault and the axial plane of the regional syncline. Fumerton (1997) indicates that supracrustal rocks between the Bear Head and Lower McVicar Faults have been folded into sigmoidal S-folds, and that a number of splay faults also exist in this area. The geometry of these structures has been interpreted as being consistent with a dextral sense of displacement.
|Mafic lava flow-unsubdivided||2||Adjacent|
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Mar 28, 2007 (Mark Puumala) - McKay (2004) describes the Chellow Vein as a single narrow, boudinaged quartz vein that ranges from <1 cm to 50 cm wide. Waldie (1993a) indicates that the vein is oriented 290/80 and consists of smoky grey to white quartz mineralized with minor pyrite and visible gold. The vein is reported to be hosted within a massive unit of gabbro or mafic metavolcanic rock and is exposed for a strike length of approximately 125 m. A series of 34 channel samples collected across the vein at intervals of 2 m are reported to have averaged 28.8 g/t Au. A grab sample assay of 827 g/t was reported by McKay (2004). A five hole BHP Minerals diamond drilling program reported by Waldie (1993b) returned much lower gold values, with the best reported intersection reported as 1160 ppb Au over 0.3 m. A second gold mineralized vein referred to as the Cliff Zone by Waldie (1993a) is located approximately 50 m south of the Chellow Vein. This may be the same vein referred to by Janes et al. (1989) as Occurrence No. 8. This vein is reported by Waldie (1993a) to be approximately 5 cm wide, and is oriented 300/80. Shearing observed by Janes et al. (1989) in mafic metavolcanics in close proximity to the occurrence was reported to have an orientation of 305/70. A secondary fracture cleavage oriented 140/90 was reported to approximately parallel the gold mineralized vein. The most notable assay reported from the Cliff Zone vein by Waldie (1993a) was 70 g/t Au (grab sample), while Janes et al. (1989) reported a 0.2 m chip sample assay of 1730 ppb Au. Two BHP Minerals diamond drill holes that targeted this structure (Waldie 1993b) did not return any significant assay results.
Sep 26, 2019 (Robert Cundari) - The Chellow vein lies between the southern bay of McVicar Lake and Semia Lake, just north of the Bear Head fault zone. It is a single, narrow, boudinaged, smoky grey to white quartz vein that ranges from less than 1 cm to 50 cm in width, averaging 10 to 20 cm. It strikes approximately 100°, dips almost vertically and is mineralized with minor pyrite and visible gold. The vein is hosted within a massive, fine-grained gabbro that is more fractured and sheared adjacent to the vein. This gabbro is locally brecciated by a feldspar-phyric gabbro. The gabbro body is dyke-like at the eastern end of the exposure where it has intruded folded, magnetite-bearing, banded iron formation. The shear zone narrows locally to a chloritic phyllite where the vein is absent. A series of 34 channel samples collected across the vein at intervals of 2 m are reported to have averaged 28.8 g/t Au. A grab sample assay of 827 g/t Au was reported by McKay (2004). 09 MCV-01 Chellow Vein (607418E, 5710858N): Altered banded iron formation, rusty-weathering, Fe-carbonatized BIF adjacent to gabbro dyke / fracture zone; locally magnetic; recrystallized, sugary; some calcite, very fine-grained pyrite <<1%. Assayed 0.03 oz/ton Au. 09 MCV-02 Chellow Vein (607418E, 5710858N): Quartz vein, narrow (10-20 cm), glassy, black quartz vein with <5% wispy pyrite ± pyrrhotite, chalcopyrite. Assayed 0.10 oz/ton Au.
Sep 26, 2019 (Therese Pettigrew) - The best result from the 2012 channel sampling program was 18.21 g/t Au over 15 cm (Assessment report 20000007971).
Article - Uchi subprovince
Publication Number: SV04-01.006 Scale: Date: 1997
Author: Stott G.M., Corfu F.
Publisher Name: Ontario Geological Survey
Article - Regional-scale shear zones in Sachigo Subprovince and their economic significance
Publication Number: MP141.006 Scale: Date: 1997
Author: Osmani I.A., Stott G.M.
Publisher Name: Ontario Geological Survey
Article - Sioux Lookout Resident Geologist's District - 1988
Publication Number: MP142.004 Scale: Date: 1997
Author: Janes D.A., Seim G.Wm., Storey C.C.
Publisher Name: Ontario Geological Survey
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