Ontario Mineral Inventory

Ontario Geological Survey
Permanent Link to this Record: MDI53A12SE00004

Record: MDI53A12SE00004

General

Commodities

Primary Commodities: Niobium, Phosphate

Secondary Commodities: Uranium

Location

Township or Area: Schryburt Lake Area

Latitude: 52° 36' 12.21"    Longitude: -89° 37' 12.15"

UTM Zone: 16    Easting: 322577.22   Northing: 5831376.44    UTM Datum: NAD83

Resident Geologist District: Thunder Bay North

NTS Grid: 53A12SE

Point Location Description: Precise

Location Method: Data Compilation

Access Description: Schryburt Lake is located approximately 128 km northeast of Pickle Lake and is accessible by float-equipped aircraft.

Exploration History

1960: 30 claims staked by Many Lakes Exploration Company. 1961: Many Lakes Exploration Company Ltd. conducted mapping, prospecting, trenching, sampling, and a ground magnetic survey. 1976: OGS staff mapped the complex. 1975-77: International Minerals & Chemical Corp. conducted geological mapping, soil sampling, and drilled 6 vertical reverse circulation holes totaling 292.6 m.

Assessment Work on File

Geology

Province: Superior

Subprovince: Sachigo

Terrane: North Caribou

Domain: Island Lake

Geological Age: Archean   Geochronological Age: 1145 +/- 74 Ma   Geochron. Age Ref.: Sage, 1983

Lithology

Lithology Comments

Sep 12, 2019 (Therese Pettigrew) - Samples collected from the pits and trenches indicate the complex is composed predominantly of calcitic carbonatite. Subvertical bands of nearly pure sovite alternate with bands of silicocarbonatite. One pit exposed a coarse-grained dolomite dike. In the carbonate, very pronounced bands of nearly pure actinolite, apatite, magnetite, biotite-phlogopite, or pyrrhotite alternate with pink to pink-white carbonate. The rocks are highly variable in colour, texture, and grain size, but generally could be classified as equigranular and medium-grained. One outcrop of granitic rock in the northeast corner of the complex is strongly fenitized and extensively cut by carbonate dikes (Sage, 1983).

Mineralization

Mineralization Comments

Sep 12, 2019 (Therese Pettigrew) - The complex is principally carbonatite and varies from nearly pure calcite to almost pure apatite with bands of massive magnetite several feet in thickness. Pyrochlore is present as an accessory mineral (Ferguson 1971). Samples from trenches done in 1961 by Many Lakes Exploration returned assays of up to 1.82% Nb2O5 from a grab sample and 0.40% Nb2O5 over 8 feet from a channel sample. Many Lakes Exploration Co. Ltd. took 55 samples, 43 of which assayed below 0.1% niobium oxide, 8 between 0.1 and 0.3%, and 4 between 0.3 and 1.82%. Perovskite is the chief source of the lower niobium values, the higher values occurring in pyrochlore associated with apatite-rich samples. Pyrochlore was present in a magnetite-rich sample from trench 21 of Many Lakes Exploration Ltd. Radioactivity was 8 to 9 times background within the bottom of the trench and the soil consisted of medium-grained, disaggregated carbonatite composed of magnetite and carbonate grains. A coherent sample was collected from a pit within the trench at a depth of approximately 1.5 metres. In thin section pyrochlore is present as dark brown, subhedral grains. It is present as isolated grains within carbonate and as grains perched on the edge of ,magnetite grains. One of the larger grains contains inclusions or blebs of carbonate. Cracks commonly radiate out from this grain. A sample of the soil, assayed for uranium and niobium, returned 0.039% U3O8 and 0.08% niobium. International Minerals and Chemical Corp. drilled 6 vertical reverse circulation holes. This drilling encountered residual apatite accumulations only in hole SC-1. Within this hole 9.0 meters (30 feet) of apatite-rich residual soil returned an average assay of 17.5% P2O5, with values up to 19.6% P2O5 over 5 feet (Sage, 1983). Thin sections prepared from resistant nodules of carbonatite recovered from the carbonatite soils indicate that the rocks of the intrusion have a high carbonate content. The samples contain 10-100% carbonate, trace to 35% magnetite, trace to 0.4% zircon, trace to nearly 14% apatite, from less than 1 to more than 28% biotite, 0 to more than 26% clinopyroxene, and from 0 to more than 13% olivine. Generally minor amounts of arfvedsonite, actinolite, brown alteration, perovskite, nepheline, cancrinite, serpentine, quartz and orthoclase were identified in one or more thin sections. The nepheline noted in one section is well zoned and the zircons in one section were also zoned. The pyroxene in one section is zoned from a light brown core to a grey rim. Olivine in the same section as the zoned pyroxene is very fresh, but was serpentinized in other thin sections (Thurston et al, 1979).

Mineral Record Details

References

Article - Carbonatite-alkalic complexes

Publication Number: MP067.013 Date: 1997

Author: Sage R.P.

Publisher Name: Ontario Division of Mines

Location:

Map - Geological series, Schryburt Lake carbonatite complex, District of Kenora (Patricia Portion)

Publication Number: P2236 Scale: 1:15,840    Date: 1979

Author: Sage R.P., Wright W.

Publisher Name: Ontario Geological Survey

Location:

Mono - Geology of the Schryburt Lake carbonatite complex

Publication Number: OFR5413 Date: 1984

Author: Sage R.P.

Publisher Name: Ontario Geological Survey

Location:

Mono - Geology of carbonatite-alkalic rock complexes in Ontario: Schryburt Lake carbonatite complex, District of Kenora

Publication Number: S050 Date: 1988

Author: Sage R.P.

Publisher Name: Ontario Geological Survey

Location:

MonoMap - Geology of Winisk Lake area, District of Kenora, Patricia Portion

Publication Number: R193 Page: 123-129  Date: 1980

Author: Thurston P.C., Sage R.P., Siragusa G.M.

Publisher Name: Ontario Geological Survey

Location:

Map - Geophysical series, Obabigan Lake, Kenora District, Ontario, airborne magnetic, total field

Publication Number: M00938G Scale: 1:63,360    Date: 1998

Author: Geological Survey of Canada, Ontario Dept. of Mines

Publisher Name: Geological Survey of Canada, Ontario Dept. of Mines

Location: https://doi.org/10.4095/110384

Mono - Uranium and thorium deposits of northern Ontario

Publication Number: MDC025 Page: 79  Date: 1984

Author: Robertson J.A., Gould K.L.

Publisher Name: Ontario Geological Survey

Location:

MonoMap - Columbium (niobium) deposits of Ontario

Publication Number: MDC014 Page: 48  Date: 1971

Author: Ferguson S.A.

Publisher Name: Ontario Dept. of Mines and Northern Affairs

Location:

Report an Error

We are continuously updating our assessment file / technical report information. If you notice errors in the data, please contact us.

Terms of Use

Please review our Terms of Use agreement for this data product.

Ministry Contact Information

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