EL 8915 Tee Dee Hill Victoria River Region, NT Annual Report on Exploration Activities year four of tenure 7 June 2003 to 6 June 2004

Abstract

EL 8915 was granted to Ashton Mining Ltd on 7 June 2000. Since that time, Rio Tinto has taken over Ashton and established the diamond prospectivity of the area with a range of airborne and ground exploration techniques including considerable surface sampling. During 2002, Rio Tinto was entered into negotiation with Gravity Capital Limited concerning the deployment of the Falcon(tm) airborne gravity gradiometer system over Rio Tinto's diamond tenements in northern Australia. Gravity formed a farmin joint venture with BHP, through its 40%- owned associated company, Diamond Mines Australia Pty Ltd with Rio Tinto Exploration, concerning the diamond and base metal exploration over a large number of Rio Tinto-controlled tenements in the Northern Territory (ASX announcement 25/07/2003). EL 8915 forms part of the DMA-Rio Tinto joint venture. On the basis of these agreements, Gravity (on behalf of DMA) commenced diamond exploration in the Northern Territory during July 2003. In essence, the agreements provide for DMA to deploy the Falcon(tm) system and earn an interest in any discovery. BHP Billiton retains a right to buy into DMA's interest in any discovery. Gravity is managing all exploration for DMA. The 2003 flying program was planned to cover part of EL 8915 and focused on the area of strongly anomalous diamond indicator mineral sampling results, obtained from Rio Tinto's prior work. While the principal target in the area is diamonds, some interest is also directed toward base metal deposits. EL 8915 is located over the southern part of the Neoproterozoic Victoria River Basin. The physiography consists mainly of dissected plateaus, ridges and some alluvial plains. Occasional pronounced linear drainage patterns map the location of faults. The Victoria River Basin consists of marine and continental sediments (mainly sandstone) up to 3500m thick. The Jasper Creek sandstone of the Auvergne Group comprises most of the Neoproterozoic outcrop. In the southwest of the tenement Angalarri Siltstone overlies the Jasper Gorge sandstone. In the southeast and southwest Lower Cambrian Antrim Plateau Volcanics unconformably overlies the Auvergne Group. Deformation consists of minor tilting to broad open folding and minor faulting. Erosion of the basalt in the more recent geological past has exposed sub-circular domes of the underlying Neoproterozoic sediments. Regional NW-SE and NE-SW trending lineaments, some of which appear to be intruded by dykes, are evident from airborne magnetics data. Traversing immediately to the south the Tee Dee Hill indicator mineral anomaly is a prominent ENE-WSW drainage lineament interpreted to be a major fault that extends west for over 100 km. Jurassic diamondiferous dykes that have intruded the Victoria River Basin are located about 100 km to the NE near Timber Creek.