Ontario Mineral Inventory

Ontario Geological Survey
Permanent Link to this Record: MDI000000000182

Record: MDI000000000182

General

Commodities

Primary Commodities: Gold

Secondary Commodities: Zinc

Location

Township or Area: Tarp Lake Area

Latitude: 51° 36' 13.37"    Longitude: -90° 0' 54.27"

UTM Zone: 15    Easting: 706700   Northing: 5721185    UTM Datum: NAD83

Resident Geologist District: Thunder Bay North

NTS Grid: 52O09SE

Point Location Description: From assessment file map AFRO# 2.32421

Location Method: Data Compilation

Assessment Work on File

Geology

Province: Superior

Subprovince: Uchi

Terrane: North Caribou

Domain: Uchi

Belt: Pickle Lake

Geological Age: Mesoarchean  

Geology Comments

Dec 15, 2006 (Mark Puumala) - The Tarp Lake area gold prospects and occurrences are located in the northern portion of the Pickle Lake Greenstone Belt. These occurrences are found within a mafic metavolcanic rock dominated supracrustal sequence identified by Young (2003) as being part of the > 2860 Ma Pickle Crow Assemblage. According to Young (2003), the Pickle Crow assemblage is dominated by massive and pillowed mafic metavolcanic flows with subordinate (likely synvolcanic) gabbroic sills. MacTavish (2006) describes the mafic metavolcanic flows as being commonly well-foliated to schistose, amphibolitized, and often finely-amygdaloidal. In addition, MacTavish (2006) indicates that the mafic metavolcanics include units of pillow and hyaloclastite breccia. The gabbroic sills are described by MacTavish (2006) as fine- to coarse-grained gabbro, melagabro and ferrogabbro sills up to 200 m thick. The mafic metavolcanics are intercalated with thin, laterally continuous banded iron formation and small, discontinuous lenses of intermediate to felsic metavolcanics. A significant 90 to 125 m thick northeast-trending unit of felsic to intermediate tuff breccia to pyroclastic breccia has been reported in this area by MacTavish. Relatively thin units (up to 70 m thick) of clastic metasedimentary rocks have also been reported by MacTavish (2006). All lithologies are intruded by semi-concordant feldspar porphyry dikes. These dikes are reported by MacTavish (2006) to vary widely in thickness and lateral continuity. MacTavish (2006) also indicates that all lithologies are crosscut by late biotite lamprophyre dikes that are up to 5 m in thickness. One of these dikes is reported to contain ultramafic and country rock xenoliths, red garnets and greenish diopside. Stratigraphy in the Tarp Lake area generally faces toward the northwest, except where asymmetric folding (mainly further to the southeast in the Pickle Crow mine area) has caused reversals in the younging direction (Young 2003). The dominant geological structure in the Tarp Lake area is the Tarp Lake Shear Zone. This structure strikes northeast and forms a wide, diffuse and anastamosing deformation zone that is poorly exposed and characterized (MacTavish 2006). The mafic metavolcanic rocks affected by this shear zone are characterized by moderate to intense carbonatization, sericitization and local silicification (MacTavish 2006). This alteration zone hosts the numerous gold occurrences throughout the area. Many of the more significant gold prospects appear to be located where the Tarp Lake Shear Zone is intersected by splays and/or later fault/shear zones, or relatively competent lithological units such as porphyry intrusions, gabbro and iron formation. The cross-cutting deformation zones are most commonly reported to strike approximately northwest, east-west and north-northeast. Similar complex faulting/shearing patterns have been noted nearby by MacQueen (1987) in the vicinity of the Pickle Crow gold mine, and by McAuley and Winter (1990) in the vicinity of a number of gold occurrences in the July Falls area.

Lithology

Mineralization

Mineralization Comments

Dec 15, 2006 (Mark Puumala) - The Tarp Lake Prospect occurs within the Tarp Lake Shear Zone and consists of two mineralized zones (East and West) that occur in silicified, bleached and sulphide enriched (up to 10% py) quartz-chlorite-carbonate schist Prud'homme (1995). These mineralized zones occur approximately 60 m apart, within the hinge of an interpreted fold (Prud'homme 1995). The East Zone has been traced along strike for approximately 245 m and to a depth of 150 m, with the most notable reported assays including 7.2 g/t Au over 4.6 m in ddh GPT-90-12 (Prud'homme 1995) and 1.5 g/t over 36 m in ddh TL-29 (Boily 1997). The West Zone has also been encountered in a number of drill holes, with the most notable assay being 4.46 g/t over 5.2 m in ddh CGR-91-15 (Prud'homme 1995). Additional drilling of this prospect carried out by Berland Resources in 1998 (McCrindle 1999) encountered a massive sulphide vein that assayed 11% Zn and 4.9 g/t Au over 0.55 m in TL98-30.

Mineral Record Details

References

Map - Geological series, Precambrian geology, Pickle Lake area, western part

Publication Number: P3056 Scale: 1:50,000    Date: 1989

Author: Stott G.M., Brown G.H., Coleman V.J., Green G.M., Reilly B.A.

Publisher Name: Ontario Geological Survey

Location:

Map - Geological series, Precambrian geology, Pickle Lake area, eastern part

Publication Number: P3057 Scale: 1:50,000    Date: 1989

Author: Stott G.M., Brown G.H., Coleman V.J., Green G.M., Reilly B.A.

Publisher Name: Ontario Geological Survey

Location:

Thesis - New Structural, Geochronological, and Geochemical Constraints on the Tectonic Assembly of the Archean Pickle Lake Greenstone Belt, Uchi Subprovince, Western Superior Province

Publication Number: MSc Thesis Date: 2003

Author: Young, M.D.

Publisher Name: Queen's University

Location: Thunder Bay RGP

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:

Thesis - Stratigraphy, Structure and Gold Mineralization of the No. 5 Vein/Iron Formation Zone, Pickle Crow Gold Mines, Pickle Lake, Ontario

Publication Number: MSc Thesis Date: 1987

Author: MacQueen, J.K.

Publisher Name: Carleton University

Location: Thunder Bay RGP

Mono - The Geology and Tectonic History of the Central Uchi Subprovince

Publication Number: OFR5952 Date: 1996

Author: Stott G.M.

Publisher Name: Ontario Geological Survey

Location:

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