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Geological and Metallogenic Setting of northwest Tasmania
The northwest Tasmania joint venture project with Bass Metals Limited includes twelve Exploration Licences
(ELs) covering a total area of 732 km2 of the Mount Read Volcanic Belt. The JV includes the North
Rosebery, Leven River - Loyetea, Lynchford, Highclere, Waratah, Oonah and Whyte River Projects as detailed
within Section 5. Bass is entitled to retain its 75% interest in the tenements by sole funding Clancy to prefeasibility
study stage.
The Cambrian aged Mount Read Volcanic Belt (MRV) forms a 200 x 20km north-northeast trending belt of
dominantly calc-alkaline volcanics and volcaniclastics (Corbett 1992). The volcanics were erupted along the
western margin of a Precambrian block, now referred to as the Tyennan Block of central Tasmania and comprised a
lower eastern zone of massive lava-rich sequences and a western zone dominated by volcano-sedimentary and
volcaniclastic units and breccias. Stratigraphic and facies relationships are complex but considerable mapping
has been undertaken by numerous organisations in attempts to define prospective horizons favourable for
mineralisation.

Following previous workers, Clancy (Core et al, 2006) subdivided the lower portion of the MRV into the Central
Volcanic Complex, the eastern quartz-porphyritic sequence and the western volcano-sedimentary sequence all
of which are unconformably overlain by the felsic units of the Tyndall Group. As well as complex stratigraphic
relations, these units are disrupted by several major faults including the prominent Henty, Great Lyell and
Rosebery Faults and intruded by dolerites, quartz-feldspar porphyries and several large, Devonian aged
granitoids.
The MRV is well mineralised hosting several significant base metal deposits including Mt Lyell, Rosebery,
Renison, Mt Bischoff, Que River and Hellyer in addition to the Henty gold deposit. The felsic Central
Volcanic Complex hosts VHMS mineralisation at Mt Lyell, Hercules and Rosebery while Que and Hellyer are
located within the Mt Charter Group of the Western volcano-sedimentary sequence. Recognising that the
Mount Read Volcanic Belt is one of the most highly and variably mineralised rock units in the world (Corbett
1992), targeting by Clancy has also incorporated models for intrusion-associated tin (for example Renison, Mt
Bischoff) and nickel deposits (for example Avebury) as well as for orogenic gold deposits. Note that despite there
being no known examples of orogenic old deposits in Tasmania, the presence of placer and lode gold deposits
as well as potentially favourable Precambrian stratigraphy indicate the right model elements are present. |