Great Western negotiating Oval access agreements

Great Western Exploration (ASX:GTE) is now in the process of negotiating access agreements for drilling of Oval and Oval South, which the company anticipates will be completed in early 2024.

The company today (18 December 2023) reports further increased prospectivity following data interpretation at Oval and Oval South, where it is exploring for giant Winu-style (2.88Mt copper-7.88Moz gold) intrusive related copper-gold targets.

These ‘giant’ Oval and Oval South targets are within the Yerrida North Project, located on the northern and western portions of the Yerrida Basin, some 800km north-east of Perth and adjacent to the DeGrussa and Monty Cu-Au Volcanic Hosted Massive Sulphide deposits (VHMS).

The Oval and Oval South Targets were originally defined by Rio Tinto Tempest airborne EM survey in the late 1990s. Rio Tinto drill tested the Oval target, drilling a hole to a depth of 232m and terminating the hole within black shale with disseminated pyrite, considered at the time to be the source of the conductor.

In 2010 a VTEM survey was completed by Great Western over an area that encompassed both Oval and Oval South. The company says this geophysical method can penetrate deeper into highly conductive terrains such as shales at this location than the Tempest technique utilised by Rio Tinto. The VTEM data defined the conductor at a depth of 300m, below the shale surface where OVR001 was terminated, hole OVR001 did not intersect the conductor.

The geophysical signatures are interpreted by Great Western as sharing similarities with the colossal intrusive related copper-gold Winu. Further interpretation of geophysical data (gravity and magnetics) by Great Western defined a north-east trending feature.

The company’s independent interpretation was found to align perfectly with Geological Survey Western Australia’s (GSWA) major basin defining ‘growth fault’ of the Yerrida Basin interpretation completed in 2000, undertaken without the extensive geophysical dataset Great Western now has.

According to the GSWA in its report on the Yerrida Basin, this fault played a crucial role in development of the Basin. The Yerrida Basin Growth Fault is a long-lived structure, likely to have penetrated Archean Basement below the Yerrida Basin.

Great Western says crucially for Oval and Oval South, this feature intersects the crustal scale mantle tapping Ida Fault. The Company interprets these faults in conjunction provided the plumbing to focus metal rich fluids from the mantle in favourable trap sites and Yerrida Basin stratigraphy (shales, carbonates, and siltstones).

This identification of the Yerrida Basin growth fault significantly increases the potential for a giant Winu-Haverion style intrusive related copper-gold discovery to be made.

Great Western is a copper, gold, and nickel explorer with a world class, large land position in prolific regions of Western Australia. The company’s tenements have been under or virtually unexplored. Numerous field work programs across multiple projects are currently underway and the company is well-funded with a tight capital structure, providing leverage upon exploration success.

Write to Adam Orlando at

Images: Great Western
Author Image
Written By Adam Orlando Editor-in-Chief Adam Orlando has more than 20 years’ experience in the media having held senior roles at various publications, including as Asia-Pacific Sector Head (Mining) at global newswire Acuris (formerly Mergermarket). Orlando has worked in newsrooms around the world including Hong Kong, Singapore, London, and Sydney.