- SMDI #
- 1324
- Current Showing Name
- Dubyna Mine
- Historical Showing Names
- Donaldson Lake Fracture Zone or 31 Zone or Dubyna Lake Uranium Deposit or Mine, Dubyna Mine
- Company Name
- Cameco Corporation
- Project Name
- Beaverlodge
- UTM Easting (NAD83 Z13)
- 309049.5000
- UTM Northing (NAD83 Z13)
- 6610301.4000
- NTS Sheet
- 074N09
- TRM (Township-Range-Meridian)
- 122-14-3
- Primary Commodities
- Uranium
- Associated Commodities
- Fluorspar, Graphite, Iron, Lead, Molybdenum, Sulphur
- Discovery Type
- Status
- Deposit: Post-Production [Institutional Control Program]
- Geological Details
- The Dubyna Mine is located3 km (1.86 miles) northeast of the Verna Mine shaft
The deposit consists of several important occurrences of radioactivity. The showings occur on the south limb of the Donaldson Lake anticline within what is called the Donaldson Lake Fracture Zone. The fracture zone is underlain by a northeast-trending mass of reddened and brecciated granite between the St. Louis and Donaldson Lake faults. All of the fractures which exhibit radioactivity are filled with carbonate and or quartz and have intensive wall rock alteration by hematization and carbonatization. The alteration has produced a fine grained, brick red rock in which the original mineralization and character rock is destroyed from inches to feet from the fractures. Wide carbonate veining and brecciation within fractures has been noted in some cases.
The majority of the uranium mineralization is found as fracture coatings and space filling in the veining material and disseminated in the surrounding alteration zones. Pyrite is a common accessory and fluorite associated with carbonate veining is noted in some places. Radioactivity outside of the alteration zone is sporadic and usually confined to single fractures.
The Donaldson Lake Fracture Zone is as much as 400 feet (121.9 m) wide and has been traced for more than 5000 ft (1524.0 m). It lies subparallel with the St. Louis fault. Numerous pitchblende-bearing fractures have been detected at intervals over a 3000 ft (914.4 m) length of the fracture. Two main sets trend east and 060°. Trenching of the fractures returned high values across narrow widths except across for the 31 Zone, which is a pitchblende-bearing zone of veins within the Donaldson Fracture Zone, spatially related and oriented parallel to the Donaldson Lake Fault and a less well-defined subsidiary structure, the Carbonate Fault.
Approximately 1.7 million lbs U3O8 have been outlined as well as two other mineralized zones at depth.
The 31 Zone, the main pitchblende-bearing zone, consists of an en-echelon series of mineralized veins within the 070°-trending Donaldson Lake Fault approximately 900 ft (274.3 m) southwest of Dubyna lake. This orebody has been traced along strike for 1500 feet (457.2 m). The individual veins strike east-west, dip steeply south, and are 2 to 4 feet (0.6 to 1.2 m) wide. Although many radioactive veins exist in the vicinity of the 31 Zone, the fractures containing veins with ore grade mineralization do not outcrop, but occur down dip on the Donaldson Lake fault. Pitchblende occurs in diffuse irregular veins with or without calcite, dolomite, pyrite, quartz, fluorite, and graphite gangue minerals. Elements present in ore samples which area enriched relative to average concentrations in the crust include lead, sulphur, molybdenum and vanadium.
The 31 Zone is underlain by an area of Tazin Group hematized, carbonatized and anomalously radioactive granite. Outcrops of granite at the zone are underlain by mafic and leucocratic gneiss. Minor carbonate breccia, amphibolite, and quartzite are present.
1979 drilling discovered a possible extension at depth of the orebody. Almost all of the radioactivity is associated with discontinous tension fractures that strike 095° and dip south at 65° to 85°. The mineralization is probably en-echelon in cross section.
- Geological Domain
- Beaverlodge
- Host Rocks
- Host Minerals
- Fluorite, Hematite, Molybdenite, Pyrite
- Indicators
- Exploration History
- 7/28/1989 The area was staked by St. Louis for Eldorado Mining and Refining (1944) Ltd. in 1947. The following two years the claims were geologically mapped at a scale of 200 ft to one inch and prospected in detail by Eldorado. Thirty three radioactive occurrences were discovered in 'brick-red granite' at intervals for a length of 3000 ft (914.4 m) and a total of 11792 ft of drilling was completed in 12 holes. No further work was done in the area for 13 years, although strong mineralization with some degree of continuity was encountered.
The fracture zone was again geologically mapped and prospected as well as radiometrically surveyed in detail in 1967 to 1968 by Eldorado. A few new occurrences were outlined near the 31, Zone, an important deposit which is anomalously high in radioactivity and whose upper part is coincident with part of a broad, irregular total count radiometric anomaly, approximately twice background, which lies south of Foot Bay and extends from Dubyna Lake to Emar Lake.
A diamond drilling program was initiated in 1974 to test mineralization encountered in previous holes. This drilling confirmed an interpretation that although some of the mineralization is within steeply dipping fractures, zone or veins of mineralization have a rather shallow dip. A total of 34,714 feet of systematic diamond drilling was completed during 1974 to 1975 in order to outline and test the zone. In addition, 9,545 feet of percussion drilling was completed to delineate near surface mineralization. An additional diamond drilling program designed to explore the down dip projection of the Donaldson Lake Fault was completed in 1976. It appears that at least one and probably two repetitions of the 31 Zone exist in a southwest direction. Several geophysical surveys including airborne radiometric surveys, VLF-EM and magnetic surveys were completed but were of little help in defining the area of interest.
The near surface mineralization was mined by open pit methods but underground access was used to exploit the bulk of the reserves. In 1978, Redpath Engineering completed a 1800 ft (548.6 m) decline ramp 450 ft (137.2 m) south of Dubyna lake. Four levels of drifting were completed at vertical depths of 90, and 120, 300, and 400 ft and a ventilation raise were also completed.
Between 1978 and 1979, further diamond drilling was completed in the immediate area to assess the known showings and to explore the possibility of an up-dip extension of the Dubyna Deposit (AF 74N09-0281). As well, geological mapping, trench sampling, and ground VLF-EM and radon surveys were completed over the area. The drilling ruled out an up-dip extension of the ore zone and the drill program discovered new mineralization that possibly represents a continuation of the deposit with depth. 9/9/2020
ICR - 26 (Beaverlodge - JO-NES) [CR-1007]
https://www.saskatchewan.ca/business/agriculture-natural-resources-and-industry/mineral-exploration-and-mining/institutional-control-program
- Production History
- Production Period: 1979-01-01 to 1982-06-01
(open pit)
137,616.00 tons
Near surface ore was mined by open pit means and underground access was used to recover the bulk of the ore. In 1978, a 1800 ft (548.6 m) decline and underground workings on the 90, 120, 300, and 400 foot levels (27.4, 36.6, 91.4, and 121.9 m) levels were completed.
Between 1979 and June of 1982, 137,616 tonnes of ore, containing 250,880 kg U3O8, were mined and processed.
Summary:
- Uranium: 250,880.00 kilograms
- Reserves and/or Resources