Completed 2017 Coompana Drilling Program
The Coompana Province, located between the Gawler Craton to the east, the Musgrave Province to the north and the Madura Province to the west, straddles the South Australian-Western Australian border along Australia’s southern coastline. The basement geology and mineral prospectivity of this vast region is poorly understood because there are no known rock exposures due to extensive Neoproterozoic to Cenozoic cover sediments of the Officer, Denman, Bight and Eucla basins. Very little exploration drilling to test the hidden basement rocks of this region has ever been undertaken.
A location map showing eight completed drill holes in the Coompana province of South Australia.
Drill targets were carefully designed to test various geophysical domains interpreted from recently acquired Coompana Magnetic and Radiometric Survey and the PACE Copper Coompana Gravity Survey.
Geoscience Australia undertook a mixture of pre-drilling geophysical surveys, including magnetotelluric, seismic reflection and passive seismic at historical to help identify the drill targets. The geophysical surveys characterised the thickness and nature of cover at each drill site to assist with drill program planning.
The geoscientific research drilling was successfully completed at 8 drill sites in 2017. More than 1,500 m of new oriented HQ3 diamond core samples of the Coompana crystalline basement were collected. Downhole gamma and temperature logs were acquired in each of the drill holes to constrain the stratigraphy of the cover units and thermal structure of the Coompana basement rocks.
Collaboration
The Geological Survey of South Australia (GSSA), Department of the Premier and Cabinet in partnership with Geoscience Australia completed the $3 million regional pre-competitive geoscience research drilling program. The collaborative program was jointly funded by South Australia’s PACE Copper Initiative and the Commonwealth Government’s Exploring for the Future program. The drilling contract was awarded to the South Australian based Boart Longyear Australia Pty Ltd (Boart Longyear) via an open competitive tender process.
Outputs
- Magnetotelluric and seismic reflection pre-drilling geophysical data is available on the Geoscience Australia website.
- Geophysical data packages are accompanied by GA Records detailing the data acquisition, processing and interpretation methodologies for estimating cover thickness.
- Preliminary field-data reports that summarise the drill hole completion data, field stratigraphic and lithological logs and down hole geophysical data are available via the South Australian Resources Information Gateway (SARIG).
- Geological Survey of South Australia (GSSA) geoscientists are in the process of comprehensively characterising the Coompana core samples at the South Australian Drill Core Reference Library. All Coompana drill core has been scanned using the HyLogger™ and Minalyze XRF scanning instruments and structural, geochemical, mineralogical, petrophysical and geochronological analysis is underway. The new analytical data will be used to build a new model of the geological evolution of the Coompana Province which will provide a framework for understanding the mineral potential of the region.
- A synthesis report on the results of the drilling program and subsequent analysis of core samples is available for download via SARIG.
Boart Longyear drill rig used to retrieve core samples in Coompana, South Australia.
Related information
Lithospheric structure and melting processes in southeast Australia: New constraints from joint probabilistic inversions of 3D magnetotelluric and seismic data
Manassero, M.C., Özaydın, S., Afonso, J.C., Shea, J.J., Ezad, I.S., Kirkby, A, Thiel, S., Fomin, I., Czarnota, K. Journal of Geophysical Research: Solid Earth, Volume 129, Issue 3. (2024)
A regolith lead icoscape of Australia
Desem, C.U., de Caritat, P., Woodhead, J., Maas, R., Carr, G. Earth System Science Data, Vol.16, Issue 3. (2024)
Solid Geology Mapping
Our understanding of the geological history and resource potential of Australia has been underpinned by over half a century of surface geological mapping.
