Kiana Projects Summary
1. Introduction
Eureka Energy, through its wholly owned subsidiary, Kiana Projects Pty Ltd, is the holder of Exploration Licence 23639 (Kiana Licence) covering 264 km2 located about 950km southeast of Darwin in the Northern Territory of Australia. Geologically, the licence covers the southern section of the Batten Trough in the McArthur River Basin on the North Australian Craton. This region contains copper-lead-zinc-silver-barium occurrences, base-metals (copper-lead-zinc-silver) deposits at McArthur River and diamondiferous kimberlites nearby at Merlin.
The prospectivity of the Kiana Licence was initially identified by reviewing its geological setting and mineral-deposit styles in the region as well as mineral occurrences, previous exploration activities, and results on the tenement. Base-metal prospectivity was identified by the presence of outcropping Proterozoic rocks on the tenement that represent the southern extension of the Batten Trough within the McArthur River Basin.
2. Prospectivity and Past Exploration
The Kiana Licence is prospective for base-metal mineralization and diamondiferous kimberlitic rocks. Four occurrences of copper mineralization in Palaeoproterozoic rocks show that the processes associated with base-metal accumulation have been active in the area. Drainage sampling for diamond indicator-minerals has reported chromite and micro-diamonds sporadically across the licence suggesting that diamondiferous kimberlites may also be located on the tenement.
The region is located on the North Australian Craton in the southern section of the McArthur River Basin near the northern margin of the overlapping Georgina Basin. The tenement is proximal to the following areas.
- 70km south of the giant McArthur River base metal deposit.
- 50km south west of the diamondiferous Merlin Kimberlites and 35km south-south east of the diamondiferous Abner Range breccia pipe.
The tenement has undergone previous exploration for base metals and diamonds with both copper mineralization and diamond indicator minerals reported. Copper occurrences in Palaeoproterozoic rocks adjacent to major faults structures in the western section of the licence indicate potential for replacement-style base-metal mineralization. In addition, diamond indicator minerals (chromite and micro-diamonds) are reported from drainages in Palaeoproterozoic folded and lightly metamorphosed rocks in the west of the tenement and less deformed Cambrian rocks overlying a Palaeoproterozoic basement in the east.
Previous exploration for base-metals in the region has identified copper occurrences in the Palaeoproterozoic rocks in the western section of the tenement. According to the Northern Territory mineral deposits database, three of the occurrences are classified as disseminated stratabound accumulations of copper minerals (bornite and chalcocite or chalcopyrite with secondary bornite and chalcocite) sometimes with galena, pyrite and sphalerite. The remaining occurrence is classified as a hydrothermal copper deposit with open-space filling of chalcopyrite with secondary bornite and chalcocite and a gangue of calcite in a sequence of siltstone and dolomite.
Results from past diamond exploration programmes in the region have delineated a major micro and macro-diamond anomaly approximately 8km west of the Kiana Licence and traces of chromite and micro-diamonds within the tenement. In total, the Kiana Licence contains 163 drainage and loam samples that were processed for indicator-mineral recovery. In total, seven samples report micro-diamonds and six samples report chromite. The distribution of grains on the tenement shows that drainages from both the Palaeoproterozoic rocks in the West and the Cambrian rocks in the East report traces of chromite and diamond. The distribution of grains suggests that Palaeozoic or older pipes could be present on the tenement.
3. Geology
Outcrop on the Kiana Licence has the north-south folded and faulted Palaeoproterozoic rocks of the McArthur Basin (Tawalla Group and overlying McArthur Group) as a basement that is unconformably overlain by generally flat-lying Bukalara Sandstone of Cambrian age. In places, the Bukalara Sandstone is capped by recent deposits of soil and laterite.
Figure 1. Location & geology of the Kiana Deposit