Ontario Geological Survey
Permanent Link to this Record:
MDI52O07SW00006
| Record Name(s) | North Dempster Lake - 1984, Wright Lake # 6 - 1990, Dempster Lake - 1984, Ontario Gold Joint Venture - 1985, North Peninsula - 1990 |
|---|---|
| Related Record Type | Simple |
| Related Record(s) | |
| Record Status | Occurrence |
| Date Created | 1990-Nov-28 |
| Date Last Modified | 2022-Jul-06 |
| Created By | |
| Revised By |
Primary Commodities: Gold
Township or Area: Wright Lake Area
Latitude: 51° 15' 48.88" Longitude: -90° 54' 51.08"
UTM Zone: 15 Easting: 645522.792 Northing: 5681202.879 UTM Datum: NAD83
Resident Geologist District: Thunder Bay North
NTS Grid: 52O07SW
Point Location Description: Drill hole DH87-04 located 50 m from the southeast shore of the north peninsula of Dempster Lake.
Location Method: Data Compilation
Access Description: The North Dempster Lake occurrence is located about 55 km southwest of Pickle Lake on the west shore of a small peninsula at the north end of Dempster Lake. Access to Dempster Lake is by appropriately equipped aircraft.
1984: Dunlop Explorations working for Ontario Gold Joint Venture (Northern Dynasty Explorations Ltd, and Newfield Minerals Inc.) conducted a prospecting and sampling program in the Dempster Lake area and discovered the Sudbury Point occurrence. 1985 to 1988: The Ontario Gold Joint Venture (Northern Dynasty Explorations Ltd, and Newfield Minerals Inc.) conducted an exploration program on a large block of claims in the Dempster Lake area. The multi-phased program included geological mapping, stripping and trenching, rock and soil geochemistry and airborne mag and EM surveys, ground mag and EM surveys and diamond-drilling. 1986: St. Joe Canada Inc. commissioned airborne mag and EM surveys which included the area of this occurrence.
| Office File Number | Online Assessment File Identifier | Online Assessment File Directory |
|---|---|---|
| 52O06SE-0032 | 52O06SE0072 | 52O06SE0072 |
| 52O06SE-0033 | 52O07SW0499 | 52O07SW0499 |
| 52O06SE-0040 | 52O07SW0032 | 52O07SW0032 |
| 53B14NE-0020 | 52B14NE0581 | 52B14NE0581 |
| 52O07SW-0018 | 52O07SW0026 | 52O07SW0026 |
Province: Superior
Subprovince: Uchi
Terrane: North Caribou
Domain: Uchi
Belt: Meen-Dempster
Geological Age: Neoarchean
Dec 07, 2005 (B Nelson) - The North Dempster Lake gold occurrence is similar to the Sudbury Point gold occurrence. The differences between the two occurrences are in the absence of the intermediate dykes and in the attitudes of the various structural elements at the North Dempster Lake gold occurrence. The gold mineralization is still associated with quartz-tourmaline veins filling tension gashes in the quartz-feldspar porphyry. At the North Dempster Lake gold occurrence, a quartz-feldspar porphyry dyke over 6 m in width cuts through felsic metavolcanics. The dyke strikes 110 degrees, parallel to the S2 schistosity. The S1 schistosity, which penetrated only the felsic metavolcanics, strikes 080 degrees and dips 060 degrees north. Most of the quartz-tourmaline veins in the quartz-feldspar porphyry dykes trend between 000 degrees and 040 degrees though some of the veins trend 330 degrees. The dip of the veins is highly variable, from almost horizontal to near vertical.
| Rock Type | Rank | Composition | Texture | Relationship | Vein | 1 | Quartz-Tourmaline | Contains |
|---|---|---|---|---|
| Quartz-Feldspar Porphyry | 2 | Host | ||
| Felsic lava flow-unsubdivided | 3 | Near |
| Rank | Mineral Name | Class | Economic Mineral Type | Alteration Mineral Type | Alteration Ranking | Alteration Intensity | Alteration Style |
|---|---|---|---|---|---|---|---|
| 1 | Pyrite | Economic | Ore | ||||
| Sericite | Alteration | Unknown | 1 | ||||
| Tourmaline | Alteration | Unknown | 2 | ||||
| Carbonate | Alteration | Unknown | 3 |
Dec 07, 2005 (B Nelson) - The Ontario Gold Joint Venture has reported assay values for grab samples of porphyry and quartz-tourmaline vein ranging up to 12100 ppb Au.
Dec 07, 2005 (B Nelson) - There is an interesting change in the alteration near the North Dempster Lake gold occurrence. The intensity of the carbonatization is decreased and tourmaline crystals have developed along the S2 schistosity planes in the felsic metavolcanics. Except for the lack of pyrite, the felsic metavolcanics are similar in appearance to the felsic metavolcanics that host the Hasaga deposit some 26 km to the east.
| Rank | Classification |
|---|---|
| 1 | Lode (Gold) |
| Rank | Characteristic |
|---|---|
| 1 | Vein |
File - Resident Geologist files AF SL 1986 52O02NW-0040
Publication Number: Date: 1996
Author:
Publisher Name:
Location: Kenora RGP
File - Resident Geologist files AF SL 52O02NW-0039
Publication Number: Date:
Author:
Publisher Name:
Location: Kenora RGP
File - Resident Geologist files AF SL 52O07SW-0016
Publication Number: Date:
Author:
Publisher Name:
Location: Kenora RGP
Article - Sioux Lookout Resident Geologist's District - 1989
Publication Number: MP147.004 Page: 69-100 Date: 1997
Author: Janes D.A., Seim G.Wm., Storey C.C.
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 Date: 1993
Author: Seim G.Wm.
Publisher Name: Ontario Geological Survey
Location:
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