Ontario Geological Survey
Permanent Link to this Record:
MDI52A04SE00022
| Record Name(s) | Phelps Dodge Corporation - 1968, Pine River-Mount Mollie - 1979 |
|---|---|
| Related Record Type | Partial |
| Related Record(s) | |
| Record Status | Occurrence |
| Date Created | 1979-Aug-01 |
| Date Last Modified | 2022-Mar-02 |
| Created By | |
| Revised By |
Primary Commodities: Copper, Nickel
Secondary Commodities: Palladium
Township or Area: Crooks
Latitude: 48° 3' 35.83" Longitude: -89° 31' 48.76"
UTM Zone: 16 Easting: 311483 Northing: 5326061 UTM Datum: NAD83
Resident Geologist District: Thunder Bay South
NTS Grid: 52A04SE
Point Location Description: DDH locations in AFRI 52A04SW0068
Location Method: Conversion from MDI
1966: Whitegate Mining Company Ltd. carried out a magnetometer survey and drilled 2 DDH totalling 287.7 m. 1968-69: Phelps Dodge Corp. of Canada Ltd. carried out magnetometer surveys and drilled 7 DDH totalling 3027.9 m. 1998: Falconbridge Ltd. conducted mag and IP surveys. 2001: McVicar Minerals Ltd. conducted prospecting and sampling. 2008: M. Luski and L. Hordy conducted prospecting and sampling.
| Office File Number | Online Assessment File Identifier | Online Assessment File Directory |
|---|---|---|
| 21 | 52A04SW0065 | 52A04SW0065 |
| 2.38796 | 20000003158 | 20000003158 |
| 13 | 52A04SW0068 | 52A04SW0068 |
| 2.22426 | 52A03SW2005 | 52A03SW2005 |
| 63.2363 | 52A04SW0054 | 52A04SW0054 |
| 2.18976 | 52A04SE2003 | 52A04SE2003 |
| 63.2365 | 52A04SW0057 | 52A04SW0057 |
| 2.18950 | 52A04SE2002 | 52A04SE2002 |
Province: Southern
Formation Group: Animikie Group
Geological Age: Mesoproterozoic
Feb 26, 2018 (Therese Pettigrew) - The Animikean sedimentary rocks were intruded by tholeiitic diabases, the Logan Sills, which are considered to be at least 1.4 billion years old, by olivine diabase dikes, Pigeon River intrusions with dates ranging from 1.2 to 1.1 billion years, and finally by the younger Pine River-Mount Mollie Gabbro part of which, the Pine River segment, has yielded a K-Ar date of 1,045 +/- 40 million years (Geul, 1973).
| Rock Type | Rank | Composition | Texture | Relationship | Gabbro | 1 | Gabbro | Host |
|---|---|---|---|---|
| Terrigenous-Clastic-Unsubdivided | 2 | Adjacent |
Feb 26, 2018 (Therese Pettigrew) - The Pine River-Mount Mollie Gabbro represents two segments of an east-west-striking intrusion, which appears to postdate the emplacement of the Pigeon River diabase dykes, as indicated by the field relationships at Mount Mollie and near the gravel pit along Memory Road and also by interpretation of magnetometer surveys. The Pine River segment, which is poorly exposed, forms an interconnected system with the upper part of the Crystal Lake Gabbro in Pardee Township. The Pine River and Mount Mollie segments are separated by an area about 914 m across, covered by more than 30 m of overburden. Magnetometer surveys and diamond drilling by Phelps Dodge Corporation of Canada Limited in areas of poor exposure indicate that the gabbro is a continuous body with an east-west strike length of over 9.65 km. Field evidence and diamond drilling shows that the dip of the gabbro contacts varies from near vertical to 35 degrees north, indicating that the body has the shape of a tilted, truncated cone in cross-section. The exposed width ranges from about 61 m up to 305 m, depending upon the attitudes of the contacts. True thickness is about 61 m, except for part of the Pine River segment which is about 305 m wide. In thin section, the gabbro ranges in composition from an anorthositic gabbro to olivine gabbro and quartz gabbro. The gabbro is composed essentially of pyroxene and zoned labradorite (Geul, 1973).
| Rank | Mineral Name | Class | Economic Mineral Type | Alteration Mineral Type | Alteration Ranking | Alteration Intensity | Alteration Style |
|---|---|---|---|---|---|---|---|
| 1 | Chalcopyrite | Economic | Ore | ||||
| 2 | Pyrrhotite | Economic | Ore | ||||
| 3 | Ilmenite | Economic | Ore |
Feb 26, 2018 (Therese Pettigrew) - Assays from 1966 drilling ranged from 0.04-0.30% Cu and 0.01-0.13% Ni (AFRI 52A04SW0065). A sample collected in 2008 along Highway 61 returned assays of 4916 ppm Cu and 4255 ppm Ni (AFRI 20000003158). Geul (1973) classified this deposit as a syngenetic Cu-Ni sulphide deposit and reported that the drilling by Phelps Dodge established a close association of chalcopyrite and nickeliferous pyrrhotite mineralization with anorthositic phases of mafic intrusions mainly olivine gabbro. Commonly copper-nickel mineralization occurs as nickeliferous pyrrhotite, with visible chalcopyrite as rims around the pyrrhotite blebs, and is found in locally near-massive fracture fillings, and disseminations marginal to, but also locally within, olivine diabase dykes and gabbroic equivalents. On the basis of airphoto interpretation, geological mapping, geophysical surveys, and diamond drilling, it is concluded that the Pine River-Mount Mollic gabbro body is an east-west-trending, crosscutting grossly banded intrusion, characterized by a relatively coarse granularity, a notable ilmenite content, and a leucogabbroic composition. It may be regarded as equivalent in age to the Crystal Lake Gabbro and to a phase of the Duluth Gabbro Complex.
| Rank | Classification |
|---|---|
| 1 | Syngenetic |
MonoMap - Geology of Crooks Township, Jarvis and Prince locations, and offshore islands, District of Thunder Bay
Publication Number: R102 Scale: Date: 1973
Author: Geul J.J.C.
Publisher Name: Ontario Division of Mines
Location:
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