Annual Report EL 28232, 29 March 2013 to 28 March 2014 Pine Creek Project

Abstract

The predictive exploration model derived during the previous period was the geological basis for this review. The critical outcomes from this review were: The recognition that the magnetic stratigraphy of the Koolpin Formation was secondary in nature, with the magnetite placement being the result of Fe-rich and acid metamorphic fluids depositing magnetite is the same low pressure dialtional zones that were optimal sites for the precipitation for the later gold mineralisation. The recognition that the original flat lying magnetic stratigraphy had be re-orientated into a subvertical orientation by thrust folding up against a competent body, possibly a concealed Archean dome. Exploration focus should be restricted to the sheared upright northerly trending and magnetic stratigraphy that approximates the Fenton shear zone trend. The recognition that the presence of greenstones in the form of intrusive dolerite bodies provide an important physio-chemical component of the gold forming process. A negative criterion is the absence of extensive greenstone volcanism, present in voluminous amounts in the highly gold endowed Proterozoic Birimian terrane. The restriction to intrusive greenstones may at Pine Creek may be a reflection of the absence large underlying tectonic and magmatic processes. The recognition that the attenuation and sheared, subvertically-orientated, eastern limb of the thrust folded stratigraphy could be seen consistently in the regional structural profile; however, this was not the optimal target when it came to local occurrences of mineralisation. Gold mineralisation appeared to be concentrated in the fold hinge. All previous exploration had focused on the eastern limb where two historical drill holes had encountered gold mineralisation. The deep diamond hole PCDD01 was drilled into this zone and did not encounter the favourable Koolpin stratigraphy or any gold mineralisation. The gold system in this area appeared to be constrained by the tight subvertical lithology. The recognition from the detailed analysis of the HyLogger examination of all previous drilling that while the hole FEND-18 intersected good thicknesses of low grade gold mineralisation, it was located in peripheral position to the central and focused position of the gold system. This was on the basis of the apparent degree of alteration, and especially the low Mg chlorite/ Fe chlorite ratio. Conversely the lower grade gold mineralisation in FEND 14 was contradictory with the mineralogy that indicated that this drill hole was actually more centrally located to the gold system. There is a marked increase in the Mg chlorite/ Fe chlorite ratios. The conclusion that the priority exploration area at the Pine Creek project was around the northern end of the tenement, where FEND14 was situated. There was a good correlation with anomalous sections of the historic Homestake Gold Australia (HGAL) soil geochemistry, and anomalous geochemistry on the northern portion of the tenement.