A gravity survey program by Strategic Elements (ASX: SOR) at its Ilkurka and Lennis projects in Western Australia’s Officer Basin has identified “very large dense bodies of material” buried within a magnetic ring structure.
The previously-unidentified anomalies sit within rings of up to 20 kilometres diameter within the remote Gibson Desert, near the border of South Australia.
They were discovered during the land-based survey and 3D inversion modelling program conducted over three weeks and utilising 1000 separate gravity stations.
While the cause of the magnetic rings is unknown – they could be the result of meteoric impacts, igneous intrusion or a mineral alteration system – their structure is well-recognised internationally to be associated with significant mineral resources.
Prominent examples are the Witwatersrand Basin in South Africa – which holds the world’s largest-known gold reserves and has produced approximately 40% of all gold ever mined on earth – and the world-class nickel-copper-platinum group elements deposits in mafic-ultramafic intrusions of Canada’s large Sudbury impact structure.
Geoscience Australia has interpreted multiple deep intrusions of the Albany Fraser Orogeny in the area around the magnetic ring features at both projects.
Albany Fraser mafic-ultramafic intrusions are well known to the market from the success of Sirius Resources’ massive Nova nickel-copper-cobalt discovery in WA’s goldfields region in 2012.
The deposit was identified by high-risk greenfield exploration and three years later, Sirius was sold for $1.8 billion to Independence Group (ASX: IGO), which today operates the Nova mine.
New target zones
The Ilkurka and Lennis anomalies have prompted the generation of new target zones for nickel-copper-gold sulphide mineralisation, often associated with very large deposits of nickel, copper, PGE and gold.
Strategic Elements managing director Charles Murphy said the company plans to explore the newly-identified zones via IP geophysical surveys designed to detect zones of disseminated sulphides which could carry these mineralisations.
“Whether the cause of the magnetic rings are from rocks intruding up from below or as some experts believe, from the impact of a meteorite coming down from above, the gravity anomalies have assisted us to generate target zones for nickel-copper-gold sulphide mineralisation,” he said.
“True greenfields exploration such as this has very high risks, but the rewards for discovering a large base metal rich sulphide deposit can also be also very high.”
At mid-afternoon trade, shares in Strategic Elements were trading 22% higher at $0.039.