Virgin River Property
Geological Setting and Other DepositsThe Tarku Uranium Project is located 20 km south of the southern margin of the Athabasca Basin straddling the boundary of the Lloyd and the Virgin River Domains which forms part of the sub-Athabasca basement complex.
The Athabasca Basin occurs within the southwestern part of the Churchill Structural Province of the Canadian Shield. The 100,000 square km basin is filled by unmetamorphosed sediments dominated by, variably hematized siliciclastic, conglomeratic sandstone that are interpreted to have filled the basin over a 200 Ma period. The basin unconformably overlies much older crystalline basement rocks with the unconformity dipping towards the centre of the basin. Drilling has shown the basin to reach up to 1,500 metres in depth.
The Archean to Paleoproterozoic crystalline basement underlying the Athabasca Basin is strongly deformed and metamorphosed and is comprised of three major lithotectonic zones; the Talston Magmatic Zone, the Rae Province and the Hearne Province. The basement underlying the Athabasca Basin is dominantly underlain by the Rae and Hearne provinces. The Tarku property overlies the boundary between the Rae (Lloyd Domain to the west) and Hearne (Virgin River and Mudjatik domains to east) provinces, demarcated by the Virgin River Shear Zone. No Athabasca Basin rocks have been identified on the property but remnant sansdstone outliers do exist elsewhere in the region.
Two types of unconformity related uranium deposits exist in the region. Polymetallic (U,-Ni-Co-Cu, Pb, Zn and Mo) such as Key Lake and Cigar Lake and monometallic deposits such as McArthur River and Eagle Point. Polymetallic deposits are sandstone hosted, occurring at the sub-Athabascan unconformity. Monometallic deposits occur from the unconformity downward along faults in or adjacent to graphitic rocks. They occur completely within the basement host rocks and can be developed for up to 500 metres below the unconformity. Due to the Tarku property's location outside the Athabasca Basin, basement hosted monometallic uranium deposits are the main target.
The most notable recent discovery of this type in the Athabasca Basin region is the Patterson Lake South (PLS), discovery of Alpha Minerals Ltd. and Fission Uranium Corp. approximately 100 km northwest of Tarku. Though not structurally related to the Tarku property and well separated spatially, the discovery history of the PLS illustrates the potential for new discoveries outside of the Athabasca Basin in prospective rocks. In November of 2012, the joint venture intersected 8.5m of 1.07% U3O8 in the discovery diamond drill hole and has now identified 5 shallow mineralized zones over a strike length of 2.24 km.
Two deposits lie along the Virgin River Shear Zone to the north of Tarku. The Centennial Deposit (Cameco Corporation 50%/Areva 50%) is approximately 45 km north along a structure related to the Virgin River Shear Zone. The deposit occurs in proximity to the Athabasca Unconformity at a depth of 600 metres, has been traced over 650 metres of strike length and has a minimum across strike width ranging from 10.0 metres to 52.5 metres. High grade U3O8 intersections up to 8.78% U3O8 over a core length of 33.9 metres have been identified at the Centennial Zone and to date some 39 uranium intercepts GT (Grade %U3O8 x metres Thickness) greater than 10 have been drilled since 2004.
The Dufferin Lake (Southwest Athabasca Project 87.5% Cameco/12.5% Areva) occurrences are approximately 25 km northwest of Tarku in a similar setting to the Centennial, though the Dufferin Lake deposit is situated at a much shallower depth of approximately 350 metres. Numerous uranium bearing intercepts have been reported, including a 1.75% U3O8 over a core length to 6.5 metres.