Ontario Geological Survey
Permanent Link to this Record:
MDI52P12NW00002
| Record Name(s) | July Falls No. 1 - 1985, Collishaw Lake A ,1 - 1985 |
|---|---|
| Related Record Type | Simple |
| Related Record(s) | |
| Record Status | Prospect |
| Date Created | 1985-Jul-29 |
| Date Last Modified | 2022-May-31 |
| Created By | |
| Revised By |
Primary Commodities: Gold
Township or Area: Collishaw Lake Area
Latitude: 51° 38' 55.72" Longitude: -89° 55' 20.73"
UTM Zone: 16 Easting: 297828 Northing: 5726024 UTM Datum: NAD83
Resident Geologist District: Thunder Bay North
NTS Grid: 52P12NW
Point Location Description: Vein in pit
Location Method: Field Visit with GPS
1948: Crowshore Patricia drills 12 DDH on veins #2, #6, #7 and #8 (J-1 to J-7).
| Office File Number | Online Assessment File Identifier | Online Assessment File Directory |
|---|---|---|
| 52P12NW0010 | 52P12NW0024 | 52P12NW0024 |
| 2.13392 | 52P12NW0005 | 52P12NW0005 |
| 2.3967 | 52P12NW9482 | 52P12NW9482 |
| 2.4899 | 52P12NW9487 | 52P12NW9487 |
| 52O08SE-22 | 52O08SE0007 | 52O08SE0007 |
Province: Superior
Subprovince: Uchi
Terrane: North Caribou
Domain: Uchi
Belt: Pickle Lake
Geological Age: Archean
Nov 14, 2006 (Mark Puumala) - The July Falls area occurrences are located at the northeast end 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, and within a mafic intrusion referred to by Stott (1996) as the July Falls Mafic Stock. According to Young (2003), the Pickle Crow assemblage is dominated by massive and pillowed mafic metavolcanic flows with subordinate gabbroic sills. The mafic metavolcanics are intercalated with thin, laterally continuous banded iron formation and small, discontinuous lenses of intermediate metavolcanics. All lithologies are intruded by semi-concordant feldspar porphyry dikes. Stratigraphy generally faces toward the northwest, except where asymmetric folding (mainly in the Pickle Crow mine area) has caused reversals in the younging direction (Young 2003). The July Falls Mafic Stock is described by Stott (1996) as a composite mafic stock consisting of phases ranging from quartz diorite to gabbro, pegmatitic gabbro and hornblendite. The structural geology of the July Falls Area is described by McAuley and Winter (1990). The earliest structures in the area appear to parallel the volcanic stratigraphy and strike approximately north-northeast to northeast. These structures are interpreted by McAuley and Winter (1990) to be cross-cut by later 060-striking shears. These shears are in-turn cross-cut by later shear/fault zones that strike approximately 335 and 100-120 respectively. These and the east-west-striking veins observed at the July Falls No. 1 prospect appear to be similar to the structures mapped by MacQueen (1987) at the Pickle Crow mine property. McAuley and Winter (1990) have interpreted mineralization at the three July Falls area gold prospects/occurrences to have a close spatial association with the intersection of the 060 and 335-striking structures.
| Rock Type | Rank | Composition | Texture | Relationship | Granite | 1 | Near |
|---|---|---|---|---|
| Vein | 2 | Host | ||
| Feldspar Porphyry | 3 | Fldp Popr | Near | |
| Mafic lava flow-unsubdivided | 4 | Contains |
| Rank | Mineral Name | Class | Economic Mineral Type | Alteration Mineral Type | Alteration Ranking | Alteration Intensity | Alteration Style |
|---|---|---|---|---|---|---|---|
| 5 | Chalcopyrite | Economic | Ore | ||||
| 10 | Galena | Economic | Ore | ||||
| 15 | Pyrite | Economic | Ore | ||||
| 20 | Pyrrhotite | Economic | Ore |
Nov 14, 2006 (Mark Puumala) - In 1948, Crowshore Patricia Gold Mines is reported by McAuley and Winter (1990) to have completed 30 trenches and 12 diamond drill holes in the vicinity of this prospect. The trenching work uncovered 5 quartz veins striking approximately 080 to 090. An additional three veins were identified as a result of the diamond drilling program. The rocks of the area have been mapped by Stott et al. (1989) as mafic metavolcanics. However, diamond drill hole logs (Waisberg 1948) indicate the presence of numerous lithologies, including andesite, dacite, rhyolite, feldspar porphyry, carbonated dikes and diabase. The drill hole logs provide evidence of strong deformation and alteration (McAuley and Winter 1990). Therefore, it is possible that the rocks logged as felsic volcanics may in fact have been strongly-altered mafic metavolcanics. Alteration includes silicification, bleaching, and carbonatization. Numerous quartz and quartz-carbonate stringers and veins are also reported. Sulphides, including pyrite, pyrrhotite, chalcopyrite and galena(?) are commonly present in the areas of strong deformation and alteration, with chalcopyrite closely associated with gold. McAuley and Winter (1990) note that this prospect is located immediately west of a 335-trending lineament that is hypothesized have a genetic relationship to the gold mineralization. Significant gold intersections reported by Crowshore Patricia and documented by McAuley and Winter (1990) include the following: 0.84 oz/ton over 2.1 feet in diamond drill hole J6-2; 0.28 oz/ton over 0.9 feet in J-2; 0.12 oz/ton over 2 feet in J6-6; and 0.46 oz/ton over 0.5 feet in J6-7.
May 31, 2022 (Q Unknown) - 1948: best assays from drilling on #6, including 0.46 oz Au/ton / 0.5 ft
| Rank | Classification |
|---|---|
| 2 | Lode (Gold) |
| 1 | Vein |
| Rank | Characteristic |
|---|---|
| 1 | Sheared |
Date: Jul 19, 2007
Geologist: Mark Puumala
Notes: On July 19, 2007 one of the quartz veins associated with this occurrence was located along the trend of several overgrown exploration pits from the original 1948 exploration program. These pits were located near the eastern edge of a high bedrock ridge. The quartz vein is approximately 20 cm wide, consists of black quartz containing trace pyrite, and has an orientation of approximately 250/75. The host rocks are mafic metavolcanics that have been silicified and carbonatized in close proximity to the quartz vein contact. An extremely large tabular piece of quartz vein float was also found approximately 15 m north of the quartz vein. This appeared to be material excavated during previous exploration activities, and is interpreted to have been located in close proximity to its source. The quartz in this float was white to black, appeared to be barren of sulphides, and contained minor iron carbonate.
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:
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:
MonoMap - Geology of the Cat Lake-Pickle Lake area, districts of Kenora and Thunder Bay
Publication Number: R207 Page: 105-12 Date: 1982
Author: Sage R.P., Breaks F.W.
Publisher Name: Ontario Geological Survey
Location:
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:
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
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: unpublished thesis, Carleton University, Ottawa.
Location: Thunder Bay RGP
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