The Mortimer Hills Project is located in the Gascoyne region approximately 290 km east of the coastal town of Carnarvon and comprises a single tenement; E09/1618 (Figure 8). The tenement area includes rocks of the Gascoyne Province, which is comprised of Meso- to Neo- Proterozoic granitoids intruded into Palaeoproterozoic metamorphic rocks. These rocks are unconformably overlain by Mesoproterozoic sediments of the Edmund and Collier Basins. These basement rocks are obscured by an extensive cover of much younger, predominantly Cainozoic, sediments.
Uranium occurrences within the tenement are primarily disseminations in metamorphic schist sequences and late stage pegmatite intrusions. Pegmatite intrusions within the area have been considered by previous explorers to display a number of similarities to the Rossing granite that hosts the world class Rossing deposit in Namibia.
Regional exploration over the tenement was conducted in the 1970’s, targeting vein or pegmatite-associated uranium occurrences. Anomalous results were returned from surface sampling and drilling. Although low levels of mineralisation were identified in surficial calcrete, the potential for calcrete-hosted uranium deposits was apparently not pursued. Reconnaissance airborne radiometric surveys were flown in the early 1980’s, however there was limited follow-up drilling, possibly because of the introduction of Australian Government policy that discouraged uranium exploration at that time.
Compilation of all historical data, surface geological mapping and geochemical sampling is being carried out over E09/1618 so that high priority drilling targets can be defined. The potential for surficial calcrete-hosted uranium mineralisation throughout the tenement will also be evaluated.
The Red Rock Project tenement; E52/2122 is located in the Gascoyne region approximately 160 km northwest of the town of Meekatharra (Figure 9). The tenement covers basement rocks of the Yarlarweelor Gneiss Complex and the Glenburgh Terrane. These basement rocks have a complex structural and metamorphic history that includes intrusion of late-stage granitoids with elevated uranium contents. Within E52/2122 an extensive cover of much younger sediments obscures the bedrock (Figure 9).
The Despair Granite, located approximately 30 km east south-east of E52/2122 (see also Figure 9), is known to host significant primary uranium mineralisation. Uranium mineralisation within the Despair Granite is structurally controlled and associated with strong potassic alteration. Historical and recent drilling by explorers has returned narrow widths of moderate to high grade (5 m@ 1069 ppm U3O8) mineralisation within broader widths of low grade mineralisation (35 km at 503 ppm U3O8 ) (ASX: FYI Release 23 June 2010). Elsewhere at Mica Bore (approximately 10 km southeast of E52/2122) uranium mineralisation with anomalous gold is associated with banded iron and radiometrically anomalous pegmatites.
No recorded historical exploration for uranium has been undertaken in the area covered by the Red Rock tenement and hence exploration is at an early stage. Analysis of the regional geophysical data suggests that the alteration zone, which is associated with uranium mineralisation at Despair Granite, extends into the Red Rock Project area. The interpreted alteration zone is spatially coincident with uranium anomalies in the airborne radiometric data and with a number of uranium soil anomalies defined in first-pass geochemical sampling completed by River Rock Energy Pty Ltd in 2009 (see also Figure 9). It is planned to carry out high resolution geophysical and geochemical surveys of the Project in order to map the extent of the interpreted alteration zone and to define drilling targets.