Exploration - Overview

The key to reinvigorating the Tennant Creek Mineral Field (TCMF) is the application of new concepts and technologies. It can be seen from the chart below that discovery (and subsequent production) of new deposits is strongly tied to the application of appropriate concepts and technology. Historically this was magnetic geophysics –the best discovery rate (and corresponding production) followed the BMR aeromagnetic survey in 1955, then reactivation of the brownfields followed the more detailed AGSO survey in 1987.

Historical Production of Tennant Creek Mineral Field

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Emmerson’s strong belief is that the decline in discovery rates (and corresponding production) does not reflect metal depletion across the TCMF; rather it is a direct consequence of the lack and application of fresh concepts and technologies. Therefore Emmerson’s exploration approach is to maximise the probability of success through the application of those concepts and corresponding prediction and detection technologies most appropriate to the deposit types.

Mineralisation in the Tennant Creek Mineral Field

The gold-copper-bismuth mineralisation of the TCMF is predominantly hosted in magnetite-chlorite-hematite ironstones or sheared variants. The ironstones and mineralisation are localised in EW to WNW trending structures that have historically been referred to as “lines”. The ironstones and mineralisation are discordant to the folded Warramunga Formation rocks and tend to be located in structural flexures, near the hinge zones of the fold axes.

Based on historical data, the mineralisation occurs in small-to-medium sized lenses within sheared ironstone. The lenses are usually high grade with most gold deposits averaging 15-20g/t and copper 2-4%. Some of the more famous mines in the TCMF include Nobles Nob, White Devil, Warrego and Juno.

A recent revision of the age dates from the Tennant Creek region now indicate a much closer temporal relationship between the mineralisation and the Tennant Creek Intrusive complex – a further factor that indicates similarities with other iron oxide copper – gold (IOCG) deposits such as Olympic Dam and Prominent Hill in the Gawler Craton of South Australia, and Ernest Henry within the Cloncurry District of North Queensland.

Furthermore the TCMF is no different to other IOCG provinces, in that the metal assemblages and concentrations vary from deposit to deposit. Some deposits, such as Nobles Nob, Juno and White Devil are predominantly gold systems; Warrego is a gold-copper-bismuth deposit; while Peko and Geko are copper-gold deposits. Similarly for uranium, although apart from a known resource at the North Star mine and reports of uranium from Edna Beryl and Warrego, its distribution and concentration is at this stage unknown.

Some primary deposits in the TCMF are hosted predominantly in magnetite ironstones (e.g. White Devil); others are mixed hematite-magnetite (Chariot) or hematite-dominant (Edna Beryl, Malbec). Shear zone-hosted gold-copper mineralisation outside of the ironstones, further indicates the diversity of mineralisation styles present in the district. Other gangue minerals include chlorite, muscovite, talc, dolomite and sericite.

The sulphide content of these primary deposits rarely exceeds 10% and common ore minerals include chalcopyrite, native gold, cobaltite and bismuthinite. The gold-dominant oxide and primary ores are generally free-milling, which can result in high recoveries (up to 98%) being achieved.

Oxidation extends up to 120 metres below the surface and, within the ironstones, results in a hematite-goethite-quartz-clay assemblage. The copper mineralisation is typically leached and depleted while the gold mineralisation can be spectacularly upgraded.

Exploration Approach

As outlined in the strategy, our exploration approach is multi faceted and aims to integrate some new concepts (as applied to the TCMF deposits) with technology most appropriate to IOCG deposit types. At the highest level this includes establishing better prediction methodologies, such as vectors to the mineralisation through enhancing our understanding of the structural and alteration syndromes of the known mineralisation. These prediction methodologies will then be coupled with the appropriate detection tools and applied in a systematic manner across the entire Emmerson tenement package. A brownfields example includes reprocessing the existing geophysics utilising forward and inversion modelling to better define the iron oxide bodies associated with the previously drilled prospects of Troy, Thrace and Marathon.

Application of New Technologies to the TCMF

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Emmerson Resources Tenement Package

The Tennant Creek Mineral Field is situated approximately 500km North of Alice Springs on the Stuart Highway, the main road link between Adelaide and Darwin. The town of Tennant Creek is approximately 1,000 km south of Darwin and 24 km south of the intersection of the Stuart and Barkly highways, the latter being the main road link with Mt Isa.

Important infrastructure running through Tennant Creek includes the Adelaide-Darwin railway and gas pipeline. Tennant Creek has a population of approximately 3,500 and is the main service centre of the Barkly Tablelands region.

The Mineral Field is one of the richest and largest Proterozoic goldfields in Australia. Gold was first mined at Tennant Creek in the 1930’s and copper was first mined in the 1950’s. Since then the mineral field has produced more than 5.5 million ounces of gold at an average grade of 19.3 g/t gold (excluding tailings retreatment) and from gold/copper mines approximately 488,000 tonnes of copper at an average grade of 2.9% copper and 4.8g/t gold.

Emmerson Resources Tenement Position

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Emmerson Business Model

In order to maximise shareholder value, Emmerson Resources have implemented a “business framework” that aims to optimise and actively manage the project pipeline where the exploration funds are always directed toward the best opportunities and that the funding is commensurate with the quality of the opportunity. Thus Emmerson Resources will initially focus across two scales – the larger scale greenfields environment aimed at discovering the next generation of IOCG deposits and will utilise such tools as the 500 X 500m spaced ground gravity geophysical survey. In parallel, the brownfields environment will be covered by a more detailed 100X50m gravity survey, low level high resolution aeromagnetic surveys, the structural and alteration studies together with directional drilling.