Drilling is underway at the first prioritised copper target of the anomaly, which has a footprint larger than the nearby Olympic Dam iron oxide-copper-gold (IOCG) project of BHP Group Ltd (ASX:BHP).
In fact, Torrens is in the same trend that also hosts the Carrapateena copper-gold deposits of OZ Minerals Limited (ASX:OZL) and BHP’s recent Oak Dam West copper deposit, which is just 40 kilometres away.
Torrens anomaly is an extensive series of gravity and magnetic targets, most of which are under the large Lake Torrens salt lake.
This has necessitated the partners adopting a unique and environmentally sensitive drilling solution.
A heli-portable drilling rig capable of drilling deep, cored holes in remote locations is drilling from custom-made pontoons, designed to protect the salt crust and anchor the drilling rig.
Holes will be drilled to depths of between 800 and 1,500 metres into dense, iron-rich rocks, interpreted to contain copper and gold mineralisation.
“Milestone for Argonaut”
Argonaut CEO Lindsay Owler said “The commencement of drilling at Torrens is a huge milestone for Argonaut.
“Argonaut’s subsidiary, Kelaray Pty Ltd, was first granted the Torrens licence in 1998.
“The company resolutely pursued access approvals to this remarkable copper target in difficult circumstances over many years.”
There are 28 distinct target zones within the broader Torrens anomaly and the JV has committed to an initial 8-10 hole program costing about $5 million.
Torrens project, copper mines and prospects on the Stuart Shelf in South Australia.
Part of more extensive program
This is part of an extensive 25-30 hole, $15 million, program which is expected to take 18 to 24 months.
The anomaly is located over the Torrens Hinge Zone, a continent-scale zone of crustal weakness that
appears to have been a conduit for mineralising fluids from the Earth’s mantle.
Drilling of the anomaly by Western Mining Corporation in the late 1970s and by the Torrens Joint Venture in 2007 and 2008 confirmed the existence of a major IOCG mineralising system beneath several hundred metres of sedimentary cover.
More drilling is required to intercept the modelled copper-gold mineralisation.
Ten 6-metre by 2.8-metre raised work platforms were transported by helicopter onto the lake and bolted together to act as a stable platform on the lake surface.
The drill rig was then flown onto the platform in 16 sections and re-assembled.
Personnel, equipment, drill consumables and other materials are also being transported via helicopter from the exploration camp to the work platform.
Potential for world-class deposit
In the event of a discovery, Torrens has the potential to host a world-class copper-gold deposit.
Argonaut has a 30% interest in the Torrens JV with Aeris holding 70%.
In September 2018, Aeris took over as manager of the joint venture.
Owler added: “Our supportive shareholders can enjoy this moment as much as the directors and management. Now the drill results can do the talking!”