The Emmerson Exploration Leases (ELs) in NSW share most if not all of the attributes of the highly prospective Ordovician-Early Silurian Macquarie Volcanic Arc in the Lachlan Fold Belt (LFB). Large gold and porphyry-related gold-copper deposits occur along this fertile volcanic belt (e.g. Cadia, Ridgeway, Northparkes, Cowal, and Gidginbung).
These first four district scale EL's occur near Wellington, Parkes, Temora and Fifield, collectively constituting some 768km2 in area and rank highly on the predictive targeting model for both epithermal gold-silver and porphyry copper-gold. Some of these targets contain historical workings and or previous exploration which support our predictive model.
These EL's are consistent with the Emmerson strategy of predicting and selecting high quality, early-stage projects where more detailed exploration will increasingly add shareholder value.
Mineral deposits that form in the porphyry-epithermal mineral environment generally have a spatial and temporal association with intermediate to felsic sub-aerial volcanic rocks and related sub-volcanic intrusions. Geologically porphyry and epithermal deposits form in magmatic arcs (both continental and oceanic) associated with convergent plate margins, such as the Macquarie Volcanic Arc in New South Wales. Deposits are thought to form at shallow crustal levels i.e. <1.5 km for epithermal and <6 km for porphyry deposits.
The main porphyry-epithermal province in Australia is the Siluro-Ordovician Macquarie Arc in New South Wales, which contains major porphyry Cu-Au deposits at Cadia (global resource of 1.31 Gt at 0.31% Cu and 0.74 g/t Au:) and North Parkes (global resource of 153 Mt at 1.03% Cu and 0.46 g/t Au). In addition to the major porphyry Cu-Au deposits, the Macquarie Arc also contains porphyry gold and high and low sulphidation epithermal gold-silver deposits such as Lake Cowal, Cargo, Peak Hill and Gidginbung. (Cooke et al., 2007; Champion et al., 2009).
The below figure schematically illustrates the relationship of different deposits to geological features within the porphyry-epithermal mineral spectrum.