Deposit/Occurrence Name: Moon Lake Occurrence
Primary commoditites: Uranium
Secondary Commodity: Thorium
Township Area: Timmerman Township
Nearest City/Town: Elliot Lake, ONT, Canada
Deposit Status: Occurrence
Last Exploration: 1955 - Anuwon Uranium Mines, Ltd.
Formation: Matinenda Formation
Grade: 0.013% U3O8
Development/Exploration type: Diamond drilling of 7 holes, totalling 4,651 feet in length.
Status: Abandoned/staking opened
History and Exploration:
In 1955, Anuwon Uranium Mines, Limited, had held an option on 15 surveyed claims located between Moon Lake, Little Moon Lake, and Bakers Bay, Matinenda Lake, in Township 161 (Now Timmermans). It was at this time when a diamond drilling program was over taken on the property that consisted of 7 surface drill holes at the time. This had also resulted in core logging that was undertaken and had been submitted for assessment credit.
In hole No. 1 casing was intersect from 0- 1 feet and it was from 1-607 feet that the Lower Mississagi Quartzite with thin radioactive pebble band was intersected. This had also included a trasional zone that was intersected from 607 to 610 feet, and granite had been intersected from 610 to 623 feet.
Drill Hole No. 2 had logged casing from 0-4 feet and from 4 to 665 feet Lower Mississagi Quartzite with thin radioactive pebble bands was intersected. This had also included 665 to 672 feet of quartz-pebble conglomerate, and Granite at 672 to 677 feet. At about 677 to 684, it was reported that greenstone was intersected before the whole had end at 684 feet.
Drill Hole No. 3 would intercept Lower Mississagi Quartzite with thin radioactive pebble bands from 0-628 feet. This had also included an intercept of granite from 682 to 685 feet before the hole had ended at 685 feet.
Drill Hole No. 4 had also intersected Lower Mississagi Quartzite with thin radioactive pebble bands from 0 to 657 feet. This had also included a transitional zone from 657.0 to 672.5 feet and granite was intercepted at 661.5 to 672.0 feet where the hole was end at 672.0.
Drill Hole No. 5 would go onto intercepting 0 to 635.5 feet of Lower Mississagi Quartzite with thin Radioactive pebble band. It was also from 635.5 to 640.4 feet that a transitional zone was encountered and basement metasedimentary rocks were intercepted from 640.4 to 648.0 feet. The end of Drill Hole No. 4 was at 648.0 feet.
Drill Hole No. 6 would in consist of casing from 0 to 3 feet, and from 3 to 653 feet Lower Mississagi Quartzite with thin radioactive pebble band was intersected. This would also include a transitional zone that was intercepted between 653 to 658.2 feet. Another intercept would include 658.2 to 668.0 feet of Metasedimentary basement rocks before Drill Hole No. 6 ended at 668.0 feet.
Drill Hole No. 7 had a casing from 0 to 1.0 feet but had rather intersected Lower Mississagi Quartzite from 1.0 to 660.7 feet. This had also included a transitional zone that was intercepted from 660.7 to 664.6 feet. Another intercept had included metasedimentary basement complex rocks from 664.5 to 671,0 feet before the hole had ended at 671.0 feet.
The conglomerate bed which was intersected in Hole No. 2 had gave an average radiometric grade of 0.013% U3O8. Its also the radioactive pebble bands that are typically less than 8-inches thick, with pebbles being less than 1/2 inch in diameter set in a pyritiferous sericitic arkose matrix. Radioactivity in this general area was also recorded to have been logged between 8 to 10 background.
The general area is overlain by the Lower Mississagi pyritic serictitic arkose matrix that's largely composed of granitic quartz conglomerate which is cut by Keweenawan Diabase Dykes. The Lower Mississagi Quartzite is known to commonly appear within the great part of the depth from the surface down to a depth of 660 feet. This also includes transitional zones that are intercepted from 660 to 664 feet below the surface. Metasedimentary basement complex rocks are also generally intercepted in all diamond drill holes from 664 to 671 feet. Small sections are also known to be composed of granite masses that are generally intercepted at 610 feet below the surface in four surface drill holes done on the property. Its also within the Lower Mississagi Quartzite where thin bands of pebbly radioactive occur. The Matinenda Formation in this general area is composed of quartzite with thin radioactive pebble bands. Minor intersections of radioactive quartz pebble conglomerate beds occur with minor pyrite and radioactivity that up to 8 to 10 times the background. In one drill hole, a 6.8-foot conglomerate bed had gave a radiometric reading of 0.013% U3O8. These beds are generally considered to be less than 8-inches thick,
The Lower Mississagi Formation is exposed as the following, with the upper members that are generally exposed between to faults as the northwest end of Rosssmere Lake in McGiverin Township. It also commonly a belt, that partcially interrupted by faults and diabse intrusions, extending from the southwest corner of McGiverin Township by Intersect, McFadden, Hastie, Surpise Lakes and the North Shore of Lauzon Lake to the Pronto Uranium Mine. Its from the east end of Long Lake that's northeast of the Pronto Mine along Spragge Creek swining east along Waugush Lake to the vicinity of Highway # 108 where the formation is cut by overlap against a basement topographic high. The entire Lower Mississagi Formation is also only exposed in vicinity of Surprise Lake and the east end of Lauzon Lake, and to the east of Waugush Lake. In addition to surface data there is considerable information from diamond drilling.
The Lower Mississagi Formation rather rests with unconformity on the surface of the Algoma Granite and relicts of the post-Algoman soilds that are normally preserved. The actual base of the Lower Mississagi Formation is marked by the onset of sorting, and bedding. This usually consists of beds of quartzite pebbles that are largely present with in the contact that may be difficult to identify particiularly in drill core. The lowermost beds which generally consist of poorly sorted, angular to subangular quartzite and microline grains that are up to 1/4 inch across, set in groundmass of continued fragments and sericite, while the latter probably had derived from the weathered granite. In some cases, pyrite is largely present within the quartzite that constitutes as a sulphide mineral but is not present in all geological environmental conditions. These foremost beds are considered to crudely grade into finer grained more sericitic material that's more significant towards the top. Interbedded wit the arkosic quartzite are beds up to 4 inches thick consisting largely of sericitic feldspar debris and quartz. On weathering these beds take on a much yellow green colour that's more pronounced than that of the quartzite. On certain outcrops these rather green bands are clearly defined by the bedding. The upper most surfaces of the quartzite and green band may also show ripple marks.
Quartzite beds are generally scattered throughout the arkosic beds or concentrated into bands generally 1-3 inches thick. These pebbles are subangular to well rounded, well sorted, and are almost entirely of vein quartz, although pebbles of chert, jasper, and occasionally, deformed clasts are similar to the sericitic green beds. Pyrite is commonly conspicuous component of the matrix of the pebble bands. The pyrite may be euhedral or anhedral, and is largely restricted to the matrix it self. Some of the main accessory minerals consists of monazite, magnetite, apatite, and zircon. These pyritiferous oligomictic pebble bands are slightly radioactive that are generally less than 3 times background. They are also similar in type to the uranium-thorium ore of the Blind River Group.
The Lower Mississagi Formation is there for determined as dominantly coarse-grained arkose-quartzite sequence derived from weathered granite and deposited in much shallow water by southeasterly flowing currents. A zone of greater thickness may also lie in the most southwest part of Long Township. Scattered pebble bands and radioactivity are some of the main characteristics of the lower part of the formation. Radioactive conglomerate that's to the east end of Lauzon Lake had additionally sparked the Blind River Staking Rush.