A project focused on the Capricorn region of Western Australia has indicated mining companies could more accurately pinpoint reserves of valuable minerals using a new water-tasting approach developed by the national science agency, CSIRO.
In research supported by the Minerals Research Institute of Western Australia (MRIWA), broad “haloes” of altered water chemistry around known deposits of gold, uranium, and other minerals were discovered where interaction with the ore systems had left distinctive traces in the water.
CSIRO Researcher, Dr Nathan Reid, led a team of scientists analysing samples of groundwater from the Capricorn region, where layers of sediment and weathering are believed to hide potential ore deposits from view.
Dr Reid explained: “Groundwater penetrates through covering sediments and interacts directly with the bedrock, dissolving trace amounts of the minerals present into solution. By sampling those waters, our instruments can essentially ‘taste’ the geology they have come into contact with.”
Where the underlying rocks contain a valuable ore deposit, the chemical flavour of that mineralisation extends much further than the concentrated mineralisation itself, according to Dr Reid, comparing this with a teaspoon of salt making a whole glass of water taste salty.
These haloes of altered water chemistry could help geologists identify areas where other ore deposits might still lie hidden below the surface, helping to focus mineral exploration in the right areas, according to CSIRO.
Chemical anomalies identified in groundwater from sediment-covered areas of the study region have already stimulated further exploration investment from companies seeking to identify undiscovered mineral deposits, according to CSIRO. Industry sponsors of the project include Marindi Metals, Thundelarra Resources, Sandfire Resources, Northern Star Resources, MMG, Gascoyne Resources, Auris Metals, RNI, Erongo Energy and Independence Group.
MRIWA CEO, Nicole Roocke, said the innovative work in this project by scientists across CSIRO, the Centre for Exploration Targeting and Curtin University will play an important role in encouraging mining industry investment in under-explored areas of Western Australia.
“This work demonstrates the exciting mineral exploration potential remaining in the Capricorn, and we anticipate this innovative approach to mineral exploration will stimulate renewed interest in many similar areas of Western Australia where we know richly endowed geology lies buried below younger rocks,” she said.
“By supporting this fundamental research, the Western Australian Government is helping to provide the mineral exploration industry with the tools it needs to invest in identifying the next generation of ore deposits in this state.”
The technical report summarising the findings of this research can be found here.
