Wild Buck

Sandstone-hosted roll-front uranium deposits with potential for in-situ recovery


Project Highlights

  • enCore Energy Corp. owns a 100% interest in the 370 acre (149 ha) Property
  • Covers uranium-bearing sandstones adjacent to and on trend with Cameco’s Smith Ranch ISR mine
  • Located within the prolific Powder River Basin along with numerous other roll-front uranium deposits

Property Overview

The Wild Buck Property consists of 18 unpatented mineral claims covering approximately 370 acres and is located approximately 6 miles northwest of the Smith Ranch ISR mine in Converse County, Wyoming.

The property contains roll-front style uranium mineralization within the Eocene Wasatch Formation and has the potential to host multiple stacked mineral horizons and roll-front systems similar to those found on the Moore Ranch Property.

enCore Energy Corp. entered into a purchase and sale agreement with Energy Fuels Inc. to acquire a 100% Wild Buck Property.

Mineral Resources

There are no current uranium resources or reserves on the Wild Buck Property.

Geology and Mineralization

The Wild Buck Property is located within the southern Powder River Basin. The basin is a north-northwest trending, asymmetrical syncline that extends from central Wyoming into southern Montana and from the western slopes of the Black Hills to the eastern flank of the Big Horn Mountains.

The area is characterized by shallow, northeast dipping strata forming low bluffs and broad flat uplands cut by gullies from recent erosion. Cretaceous and early Tertiary sedimentary and volcaniclastic rocks cover most of the surface within the basin.

Locally the surface units are members of the Paleocene Fort Union Formation and the overlying Eocene Wasatch Formation. The Fort Union Formation is a fluvial sedimentary unit consisting of fine- to coarse-grained arkosic sandstone interbedded with siltstone, mudstone, and carbonaceous material. The Wasatch formation is the youngest strata on the Wild Buck Property and contains sandstones, clays and shales. On other properties in the Powder River Basin, uranium has been mined from several sandstone horizons within each of these formations.

The uranium deposits of the Powder River Basin are classified as roll-front style mineralization produced by the dissolution, transport and deposition of uranium at irregular, active boundaries where a reducing environment balances the oxidative capacity of the uranium-bearing ground water.

The deposits of the Powder River Basin are typically multiple “C-shaped” roll fronts distorted by variations in the gross lithology of the host sandstone unit. Individual rolls range in thickness from 3 to 20 feet and may be 3,000 feet in length. The individual ore-grade beds are dispersed throughout the mineralized zone, but the mineralized sections of sandstone may approach 500 feet in thickness, as they occur in stacked deposits.

Historical Exploration

The Wild Buck Property lies just north of the Coal Hill claims and is northwest of the Smith Ranch Property owned by Cameco.

Historic exploration drilling in the 1960s and 1970s identified a mineralized roll-front system in the Eocene Wasatch Formation. The Nuclear Exploration and Development Company drilled a number of strong mineral intercepts on this property in the 1970s and Magnum (former property owners) believes the property has the potential to host multiple stacked mineral horizons and roll-front systems similar to those found on the Smith Ranch Property.

The Smith Ranch – Highland uranium in situ recovery (ISR) facility is the largest uranium producing ISR field in the United Sates.

The Wild Buck Property is a target for further exploration and has a potential target of 500,000 to 1 million pounds U3O8 at an average grade of approximately 0.07% U3O8. The potential for additional resources exists as the roll front is unexplored at both ends. There is also potential for stacked roll fronts deeper in the stratigraphic section.

The potential quantity and grade is conceptual in nature, as there has been insufficient exploration to define a mineral resource and it is uncertain if further exploration will result in the target being delineated as a mineral resource.


Mark C. Shutty,  CPG, a Consultant to the Company, is the Qualified Person as defined under National Instrument 43-101 and has reviewed and verified the information presented above.