Listen to Geoff Eupene discuss the Charley Creek results by clicking here.
The Charley Creek Project, located in the Northern Territory of Australia, is prospective for sediment-hosted uranium deposits. The area includes an extensive portion of the uranium-enriched Teapot Granite. It is situated on the southern margin of the North Australian Craton.
Crossland has a 100% interest in Charley Creek.
Uranium Exploration Activities
The Charley Creek titles lie on pastoral leases to the west-north west of Alice Springs. There are several areas of known uranium mineralization in central Australia, most of them sediment- hosted deposits in Palaeozoic basins. The Charley Creek area has not been intensively explored for uranium - or anything else for that matter - but has the elements that Crossland believes are necessary for formation of sediment–hosted uranium deposits.
Source of uranium
The uranium content of some phases of the Teapot Granite was also initially considered interesting . Previous exploration in 1977 had located values of up to 0.228% U3O8, in association with secondary uranium mineralization hosted in the granite. These would be of immediate interest if they are shown to be widespread. However, it was initially considered that these would prove an ideal source for uranium in calcrete and channel hosted deposits such as others in the district, at Napperby, Bigyrli, and Angela- Pamela.
Transport mechanism
Uranium is transported in ground water in the channel hosted models proposed for Charley Creek. In the early 1970s, CRA Exploration Pty Ltd (CRAE) measured U content in several water bores around the project area and these ranged up to 41ppb U. These values indicate that U is mobile in these ground waters, and a deposition site in the channels would accumulate this. Crossland's project are covers a much broader area than was covered by the CRAE study.
In the granite-hosted model, uranium is enriched in particular phases of the granite during emplacement. Relatively late stage, highly differentiated granites such as the Teapot Granite are considered favorable for accumulation of uranium. Often the uranium is included in minerals where it is mixed with thorium, and in minerals that are resistant to chemical attack necessary for uranium processing. These minerals are referred to as “refractory”. The nature of primary mineralization in the Teapot Granite remains unknown. However the fact that secondary minerals are abundant at surface suggests that the primary mineralization is not refractory.
Site for deposition
There are two possible deposit types, or possibly a combination of the two types in one deposit as occurs elsewhere in this region, at Napperby. Calcrete is present in the fluvial channels and is present in outcrop during field inspection; lignite is also known, and if a source of vanadium is required to precipitate carnotite, the basic intrusive bodies of the Mount Hay layered complex lie below the fluvial channels to provide this.
In 2008, Crossland conducted a successful air core drilling campaign across the valley of Charley Creek, where there is a significant accumulation of Tertiary sediment. Follow up of the results of this work are pending the issue of additional permits from the Central Land Council.
In early 2008, Crossland completed a detailed airborne geophysical survey of the entire Charley Creek Project area, on 100m line spacing. This confirmed that the Teapot Granite was highly radioactive, and contained both Thorium rich, and Uranium rich phases. Crossland has implemented a detailed ground based spectrometer survey of an area of around 40 sq. km, on 25m line spacing, at a prospect known as Cockroach Dam, after a local watering point for cattle.
The area is being geologically mapped, and small chip samples have been collected to follow up anomalies and for petrology and mineralogy.