The Torrens Project is located within the Stuart Shelf region of South Australia about 50 kilometres from Oz Minerals’ Carrapateena deposit and 75km from BHP’s Olympic Dam mine, the world’s fourth largest copper resource. The iron oxide copper-gold target (IOCG) covers a large magnetic and gravity anomaly with a footprint greater than Olympic Dam.
The project is a joint venture between Aeris Resources (70 per cent interest) and Kelaray Pty Ltd – a wholly owned subsidiary of Argonaut Resources.
The first drillhole, TD7, was completed last month and targeted a coincident magnetic and gravity anomaly defined from the FALCON geophysical survey flown early in 2018.
TD7 was located approximately 1.5km from the shoreline of Lake Torrens and was drilled to a total depth of 858.6m.
Aeris Executive Chairman Andre Labuschagne said the unique drill set-up and infrastructure requirements to allow drilling to occur on the salt crust surface of Lake Torrens had been a success.
“Whilst it is early days and logging and assays are still pending, we are very encouraged with what we have seen from this first hole,” he said.
“It is also pleasing that we have safely completed this first hole using the unique drill rig configuration.”
The drill target, whilst prospective for IOCG mineralisation, is not the highest priority target and was chosen for the first drillhole, in part, given its proximity to the shoreline (1.5km).
Drill core from TD7 will be transported to Adelaide for sample preparation (core cutting) and assaying next week, with assay results expected in towards the end of April.
Following the completion of drillhole TD7, the drill rig and site infrastructure was safely demobilized and moved a further 7km east from the Lake Torrens western shoreline for commencement of drilling TD8.
This commenced on February 23 and was the first drillhole to be drilled more than 4km from the Lake Torrens shoreline.
However, the drillhole intersected an unexpected aquifer at approximately 100m downhole on February 27, which resulted in artesian water flow and the suspension of drilling at TD8. The next drillhole (TD9) will be in close proximity to TD8 as the targeted deep gravity anomaly is still to be tested.
Stage One will involve 8 to 10 drill holes to depths of 700 to 1,500m at priority drill targets. The drilling program will be the first phase of a multiphase program that is expected to take up to two years and comprise 20 to 30 deep drill holes.
The Torrens anomaly is one of the largest and most geologically prospective IOCG exploration targets in the world.
The anomaly sits under a 250km long dry salt lake and is on the Torrens hinge zone, a continental scale zone of crustal weakness with the capacity to act as a conduit for mineralising mantle fluids.
The South Australian government approved the project in November 2017.
South Australia hosts 68 per cent of Australia’s economic demonstrated resources of copper.
The state is a globally important producer of copper, uranium and zircon and also produces iron ore, zinc, lead, silver, industrial minerals and extractive materials.Jump to next article