Over the past 12 months there has been a real ‘buzz’ amongst the South Australian exploration community regarding the Coompana Province as an emerging exploration frontier.
The Coompana Province is located in the far west of South Australia and remains almost untouched from an exploration point of view. Through their Plan for Accelerating Exploration (PACE) initiative, the South Australian Government is investing over $6.5 million on pre-competitive data and research aimed at more clearly defining the geology and prospectivity of this region.
The extensive work program is being driven by the Geological Survey of South Australia (GSSA) in collaboration with a number of government organisations and universities.
In conjunction with the work program, the South Australian Government has also released 14 Exploration Release Areas, seven of which were granted to OZ Minerals. OZ Minerals have entered into an agreement with Mithril Resources, an experienced magmatic nickel-copper sulphide exploration company, to undertake the target generation process and assess the area for potential drill targets.
David Hutton FAusIMM, Mithril Resources Managing Director, said ‘Mithril Resources welcomes the acquisition of new high-quality scientific data by the South Australian Government for the poorly understood but highly prospective Coompana Province.’
On 11 May 2017 the Women in Mining Network South Australia (WIMnetSA) hosted a technical networking lunch. The guest presenter was Dr Rian Dutch, the Coompana Drilling Project Leader at the GSSA. Rian gave a brief background on the rationale behind the project, then presented a summary of all the new data acquisition to date with accompanying interpretations. He also shared the first glimpses of diamond drill core coming out of the $3 million regional drilling program, which commenced on 9 April 2017.
To date, very little exploration work has been undertaken within the Coompana Province and it has been more than 30 years since the last serious wave of exploration went through the region. Consequently, the existing datasets are broadly spaced, limited and dated. For this reason, the GSSA performed a gap analysis to determine the key datasets and knowledge lacking to be able to provide a framework for discovery. From this process they determined the need to provide depth of cover information, a structural framework and basement map and further evidence for the tectonic and crustal evolution of the region.
In order to achieve these outcomes, new data acquisition and interpretations are underway. This includes undertaking the Eucla Gawler seismic and magnetotelluric (MT) line and an MT grid (AusLAMP), which has already highlighted major lithospheric scale structures and the positions of MT conductors. Detailed magnetic and gravity surveys have also been completed to update the existing coarse datasets. In addition, a depth to magnetic source analysis was completed by Clive Foss (CSIRO) to determine the depth of cover in the region, which is critical dataset for planning exploration programs.
The recently commenced drilling program has been designed to target different geophysical domains, as a means to ground-truth geophysical interpretations of the basement rocks. This is an effective basement mapping tool in an area with such extensive cover and no known basement outcrop. Extensive geoscientific analysis will also be completed on basement samples, which will further enhance the understanding of geodynamic setting of the region.
When asked about the Coompana Province, Dr Steve Hill, Director/Chief Government Geologist at the GSSA, said ‘Coompana is one of Australia’s greatest geological frontiers and this geoscience work program represents one of the most exciting and impactful opportunities that a geologist can have to uncover new geology for the very first time.’
Recognition of a potential subduction driven, migrating magmatic arc and crustal scale structures with coincident MT conductors, demonstrates that the Coompana Province is a highly prospective region. This is definitely a ‘search space’ to keep an eye on over the coming months, as the drilling program progresses and results continue to roll out from both the GSSA and exploration companies alike.
The talk was followed by a gourmet two course lunch and plenty of discussion and speculation on the future of the Coompana Province. The event was attended by a diverse audience including participants from the GSSA, the University of Adelaide, the exploration and mining industry and industry service providers.
WIMnetSA would like to thank BHP Billiton (WIMnetSA Gold sponsor) and OZ Minerals (WIMnetSA Silver sponsor) for their continued support and dedication to increasing networking opportunities for women working in the South Australian minerals industry.