Partial relinquishment report for period ending 23 August 2010

Abstract

Exploration license EL 25664, Mt Alone, was applied for by Imperial Granite and Minerals Limited on the 19th October 2006. The title was granted on 23rd August 2007. The license was then purchased by NuPower Resources from Imperial Granite and Minerals and NuPower became the effective owner on 12th December 2007. EL25664 forms part of the Arganara Project. The project area lies within the southeastern part of the North Australian Platform Cover successions of the highly folded Proterozoic Hatches Creek Group of the Davenport Province, unconformably overlain by flat lying Palaeozoic sediments of the Georgina Basin. The geology of Mt Alone comprises mostly Hatches Creek Group consisting of shallow marine-fluvial sediments with interlayered felsic and mafic volcanics, intruded by felsic and mafic sills and granite plutons, one of which, the Elkedra Granite outcrops in the southern part of Mt Alone. The Hatches Creek Group and sills within it were initially folded about northwest trending axes into several major upright, open to tight synclines, anticlines and then subsequently refolded about northeast trending axes and faulted into a complex terrain of arcuate domes and basins during an orogeny dated between 1800-1650Ma. This deformation was accompanied by regional metamorphism to greenschist facies and occurred prior to emplacement of the Elkedra Granite. The sediments are represented by six formations of the Ooradidgee Subgroup, seven formations of the overlying Wauchope Subgroup and three formations of the succeeding Hanlon Subgroup with a total thickness of at least 10,000 metres. The group is typified by ridge-forming arenites separated by recessive sediments and volcanics. Widespread cross bedding, ripple marks, bedding planes with mudstone or siltstone pellets, rare stromatolites, and occasional pebbly-conglomeratic beds indicate that most sediments were deposited in shallow water. Sediments of the Wauchope Subgroup outcrop sparsely in the northern part of the relinquished areas. Cambrian-Ordovician sediments are very limited in extent and confined to the flanks of the Whisky Camp and Rockhole anticlines in the relinquished area where they form mesas and plateaux.. The Early-Mid Cambrian Andagera Formation ranges from 5-40m thick, shows marked lateral variations in thickness and lithology and typically forms mesas and hills. The main lithology consists of thick bedded to massive, poorly sorted, oligomictic cobble conglomerate of subangular to well rounded clasts up to boulder size of mostly silicified arenites sourced from local Hatches Creek Group rocks, with a sparse friable matrix of sand and granules. Crude cross beds with high angle foresets up to 20 degrees are common. The formation represents fluvial and scree deposits that formed fans and terraces flanking Proterozoic ridges. Limited in extent it occurs in the north and southeast of the project, but is absent from the relinquished areas. Mid Cambrian-Lower Ordovician rocks, formerly mapped as Sandover Beds, are subdivided into four main units comprising the lowermost Arthur Creek Formation, overlain successively by Chabalowe, Arrinthrunga and Tomahawk Formations. Only the lowermost Arthur Creek Formation is present in the project area, disconformably overlying the Andagera Formation and consisting of fossiliferous organic-rich calcareous and dolomitic siltstone, silty limestone and silty dolostone. The formation interdigitates laterally with the Chabalowe Formation to the west beyond the tenement. Thicknesses vary from 68m to 181m as reported from drill holes. The formation is generally flat-lying or has dips of 2-5 degrees to the south and southeast. Weathering is deep, the calcareous matrix is mostly leached and pyrite and carbon are oxidized leaving a whitish to yellow-brown siltstone and claystone. Chert (silicification) is developed near surface and rarely at depth in the weathered zone. Outcrop is therefore poor comprising surface rubble of weathered or silicified siltstone. Two distinct facies have been identified; anaerobic and aerobic. The anaerobic facies from the deeper part of the basin consists of dark grey-black, finely pyritic, calcareous and dolomitic siltstone and calcareous mudstone with very fine millimeter-scale lamination. Carbonaceous content is very high and generally increases towards the base. The aerobic facies however is subtidal, highly fossiliferous, and bioturbated throughout with lower organic carbon content. Dark grey to black thinly laminated to wavy bedded calcilutite, dololutite, and fine grained calcarenite and dolarenite are interbedded with light grey boiclastic and peloidal medium grained calcarenite and dolarenite. These rocks are absent form the relinquished area Most pre-Cainozoic outcrops show evidence of ferruginisation or silicification. A thin calcrete crust is common over limestones, dolostones and basalts. Fans of poorly consolidated alluvial and colluvial gravel, dissected by active watercourses, have accumulated on the flanks of prominent sandstone ridges and mesas and are common at Mt Alone. Quaternary colluvial sand, soil and gravel form gently sloping fans alongside ridges and hills are widespread throughout the relinquished area and are weakly incised by watercourses. Red earth soils form a mantle up to 10m thick over the mature deeply weathered plain in the centre of the relinquished area. The soils contain variable amounts of small ferricrete granules derived from lateritised sandstone and siltstone of the Arthur Creek Formation underlying the soil. Alluvium and alluvial soils have also accumulated along watercourses and spread out over floodplains throughout the relinquished area. These floodplains are dissected by wide meandering channels of George Creek filled with sand and gravel. NuPower was initially interested in the uranium potential on the basis of widespread airborne uranium and thorium radiometric anomalies identified by NTGS surveys associated with the unconformity between the Newlands and Treasure Volcanics of the Hatches Creek Group and the overlying Andagera and Arthur Creek Formation of the Georgina Basin. Limited reconnaissance field work of the western part of the license area has shown that it is underlain mostly by extensive alluvial deposits of George Creek and minor outcrop of the Hatches Creek Group. This is of no further exploration interests to NuPower and an area of 13 blocks was therefore selected for relinquishment.