Ontario Geological Survey
Permanent Link to this Record:
MDI42D15SE00027
| Record Name(s) | Middleton (Michano) Occurrence - 1988, Railroad Showing - 1993 |
|---|---|
| Related Record Type | Simple |
| Related Record(s) | |
| Record Status | Occurrence |
| Date Created | 1997-Feb-13 |
| Date Last Modified | 2023-Aug-03 |
| Created By | |
| Revised By |
Primary Commodities: Copper
Secondary Commodities: Silver
Township or Area: Walsh
Latitude: 48° 47' 42.66" Longitude: -86° 41' 15.93"
UTM Zone: 16 Easting: 522931.67 Northing: 5404734.68 UTM Datum: NAD83
Resident Geologist District: Thunder Bay South
NTS Grid: 42D15SE
Point Location Description: Railway rock cut
Location Method: Field Visit
Access Description: The occurrence is located on the C.P.R. railway tracks east of McKellar Harbour. The occurrence is located approximately 0.5 km south of the mouth of Dead Horse Creek. The occurrence straddles the Canadian Pacific Railway at a point 2.5 km west of Middleton siding and approximately 1 km south of the railway bridge over Dead Horse Creek. Two trails access the railway and extend south from Highway 17 just east of Dead Horse Creek and at Middleton.
1988: Line cutting, ground geophysical surveys and diamond drilling; Belmoral Mines Ltd. 1991: Property examination and lithogeochemical sampling; OGS Resident Geologist staff. 1993: M. Bliss carried out mapping and sampling.
| Office File Number | Online Assessment File Identifier | Online Assessment File Directory |
|---|---|---|
| OP93-701 | 42D15SE0005 | 42D15SE0005 |
| 2.12070 | 42D15NE0017 | 42D15NE0017 |
Province: Superior
Subprovince: Wawa
Terrane: Wawa-Abitibi
Belt: Schreiber-Hemlo
Geological Age: Archean
Dec 07, 2005 (D McKay) - The occurrence is described by Schnieders et al. (1992): Local rocks are part of the northeast-trending sequence of intercalated metavolcanic and metasedimentary rocks that comprise a portion of the Terrace Bay greenstone belt and lie within the contact metamorphic aureole of the Coldwell alkalic complex (Walker 1967). Local mafic metavolcanic rocks are foliated at 260/74N and consist mainly of dark green to black, massive flows. Highly flattened, vesicular pillows are locally evident. There are some coarser-grained, gabbroic-textured rocks that are not as strongly foliated. the host rocks are weakly to moderately carbonatized, with some vuggy, sparry calcite. Pyrite occurs sparingly as widely disseminated grains. Narrow, foliation-parallel diabase dikes intrude the Archean rocks. The copper occurrence is characterized by the extensive development of malachite as a precipitate coating fracture, joint and foliation surfaces. More remarkable is the fact that cobble-sized lumps of sandy to gravely soil at the base of the rock cut have been cemented by malachite and calcite. Individual lumps may consist of 40% carbonate. The malachite-stained zone extends along the west side of the tracks for approximately 50 m, with malachite coatings developed every metre or so.
| Rock Type | Rank | Composition | Texture | Relationship | Mafic pillowed flow | 1 | Pillowed Flows | Host |
|---|---|---|---|---|
| Diabase | 2 | Diabase Dikes | Near |
Dec 07, 2005 (D McKay) - Local mafic metavolcanic rocks are foliated at 260/74N and consist mainly of dark green to black, massive flows. Highly flattened, vesicular pillows are locally evident. There are some coarser-grained, gabbroic-textured rocks that are not as strongly foliated. the host rocks are weakly to moderately carbonatized, with some vuggy, sparry calcite. Pyrite occurs sparingly as widely disseminated grains. Narrow, foliation-parallel diabase dikes intrude the Archean rocks.
| Rank | Mineral Name | Class | Economic Mineral Type | Alteration Mineral Type | Alteration Ranking | Alteration Intensity | Alteration Style |
|---|---|---|---|---|---|---|---|
| 1 | Malachite | Economic | Ore | ||||
| 2 | Pyrite | Economic | Ore | ||||
| Calcite | Alteration | Carbonatization | 1 | Unknown | Disseminated | ||
| Malachite | Alteration | Supergene | 2 | Unknown | Disseminated |
Dec 07, 2005 (D McKay) - The copper occurrence is characterized by the extensive development of malachite as a precipitate coating fracture, joint and foliation surfaces. More remarkable is the fact that cobble-sized lumps of sandy to gravely soil at the base of the rock cut have been cemented by malachite and calcite. Individual lumps may consist of 40% carbonate. The malachite-stained zone extends along the west side of the tracks for approximately 50 m, with malachite coatings developed every metre or so. Grab sampling of the occurrence in 1989 and 1991 by prospectors and Resident Geologist staff returned assay results which varied from nil to 0.064 opt Au, nil to 4.34 opt Ag, 0.055 to 13.925% Cu and 0.008 to 0.019% Zn.
Dec 07, 2005 (D McKay) - The host rocks are weakly to moderately carbonatized, with some vuggy, sparry calcite. The copper occurrence is characterized by the extensive development of malachite as a precipitate coating fracture, joint and foliation surfaces.
File - Schreiber-Hemlo Resident Geologist Mineral Deposit Files
Publication Number: Min Dep Date:
Author:
Publisher Name:
Location: Thunder Bay RGP
Map - Nipigon-Schreiber, geological compilation series, Thunder Bay District
Publication Number: M2232 Scale: 1:253,440 Date: 1973
Author: Carter M.W., McIlwaine W.H., Wisbey P.A.
Publisher Name: Ontario Division of Mines
Location:
Mono - Mineral Occurrences in the Nipigon-Marathon Area, Volumes 1 and 2.
Publication Number: OFR5951 Page: 619-621 Date: 1996
Author: Schnieders B.R., Smyk M.C., Speed A.A., McKay D.B.
Publisher Name: Ontario Geological Survey
Location:
Map - Jackfish-Middleton area, Thunder Bay District
Publication Number: M2107 Date: 1967
Author: Walker J.W.R.
Publisher Name: Ontario Dept. of Mines
Location:
MonoMap - Geology of the Jackfish-Middleton area, District of Thunder Bay
Publication Number: R050 Date: 1997
Author: Walker J.W.R.
Publisher Name: Ontario Dept. of Mines
Location:
Article - Schreiber-Hemlo Resident Geologist's District-1991
Publication Number: MP158.007 Page: 121-163 Date: 1997
Author: Schnieders B.R., Smyk M.C., McKay D.B.
Publisher Name: Ontario Geological Survey
Location:
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