Annual mineral exploration report for EL 25210 East Tanami, for the period 13 November 2007 to 12 November 2008

Abstract

Geographically the area lies within the tropics and is characterized by warm dry monsoonal to semi desert climate with daily temperatures ranging from lows of 100C in June, July and August to 480C in December, January, February. Annual rainfall ranges around a mean of 200mm albeit the variance can be considerable with occasional flooding due to rare but significant cyclonic incursions from the NW. The topography over the license area ranges from 300m to 420m AMSL. However, this relief is in fact gentle with the northern contact of the 'Coomarie Granite Dome' represented by parallel ranges of rolling hills developed over the more resistant meta-sedimentary units. The area of the dome itself is a virtual peneplain and in essence devoid of relief and largely covered by sheet wash alluvial and colluvial sand and aeolian sand. Access to the area is poor with almost all tracks in the area either virtually unused or totally abandoned. During the last half century the area has been quite extensively explored for gold, base metals and, to a lesser extent, uranium. This data has been reviewed by the staff of Oklo Uranium Limited prior to planning the work programme going forwards. The rational behind the selection of the area is briefly discussed below. Geologically, the exploration license covers the north western quadrant of the contact area of the 'Coomarie Granite Dome', cored by a Lower Proterozoic, medium to coarse grained, two mica, granite, with earlier granodioritic phases. The enveloping Middle Proterozoic (Carpentarian) meta-sedimentary units comprise basal conglomerates, sandstones and shales and siltstones of the Gardiner sandstone unit overlain by intertidal to shelf facies stromatolitic cherts, limestones and arenites of the Talbot Well and Coomarie sandstone formations. These meta-sedimentary units dip at gentle to moderate angles to the NW. The exploration model evolved for area selection was based on known mineralisation at Killi Killi discovered in the 1950's in the West Tanami. This model was, to some extent, also based on the known geology of Lower Proterozoic uranium deposits discovered in the Northern Territory of Australia and the Athabasca Basin in Canada. In these examples moderate to high grade pitchblende mineralisation is located at or near the unconformity between the underlying Archaean basement lithologies and unconformity with the overlying Lower Proterozoic clastic metasediments. In the foregoing deposits, uranium mineralisation is associated with locally intense silicification, quartz - sericite -pyrite and chlorite - magnetite - graphite alteration attended by structurally controlled shearing, shattering and brecciation at the silicified unconformity. A variety of other disseminated sulfides are associated with the uranium mineralisation including arsenopyrite, skutterudite and cobaltite. However, it is noteworthy that in E25210, the unconformity is associated with Carpentarian age Formations as opposed to the lowermost Lower Proterozoic Pargee Sandstone Formation, which does not crop out within the area of the license. Nonetheless, previous explorers in the area identified anomalous uranium mineralisation within the coarse clastic units of the Gardiner Formation.