Goyder FLOWS Stage-2 has worked towards improving broad knowledge about the location and interaction between groundwater resources in the northern part of the Eyre Peninsula area. This area is a priority area that was identified by the mining exploration industry for mineral exploration and potential mine developments.
Work undertaken in G-FLOWS Stage-2 supported the development of new hydrogeological framework using the approach developed by G-FLOWS Stage-1. This approach uses a combination of regional geophysical data (magnetics), local airborne geophysical surveys (industry supplied Airborne Electromagnetic (AEM) data sets), terrain indices derived from surface topography (using MrVBF), and existing South Australian regolith and geological data (through DSD) and hydrogeological data (through DEWNR). The hydrogeological framework supplements existing knowledge of the aquifer systems and their spatial variability in the northern Eyre Peninsula.
The project developed a methodology combining classical groundwater hydrogeology, environmental tracers, geophysics and analytical modelling. Of importance is the development of a detailed groundwater surface (water-table and potentiometric surface) map that can provide important inferences about the scale, nature and behaviour of the dominant groundwater flow systems in place.
Key aspects of the work undertaken in G-FLOWS Stage-2 include:
Application to the northern Eyre Peninsula of the hydrogeological framework, which combines and interprets multiple datasets from industry and government to help target finer-scale assessment of groundwater resources.
Application and further development of a range of approaches and techniques for interpretation and use of airborne geophysics to provide information on hydrogeology and groundwater:
Communication of scientific results to a wide range of stakeholders and audiences, which included:
Close collaboration and goodwill with data exchange between mineral companies and stakeholders, including government agencies.
The work undertaken in G-FLOWS Stage-2 can be built on in the following ways:
Examine potential of combined regional geophysical (AEM) and surface (regolith) datasets as a means of up-scaling spatial patterns of groundwater recharge, which includes on-ground follow up to improve and validate the hydrogeological framework.
Continued verification of AEM data through comparison with multiple lines-of-evidence, including :
Undertake additional work to apply the piloted Markov chain Monte Carlo (McMC) analysis of AEM data to inform hydrogeological modelling. This could include the following:
Work towards using inverted AEM datasets to provide detailed 3D geometry as part of geological and groundwater model development.
Link spatial understanding of hydraulic parameter variation (from remotely sensed techniques such as NMR) to inform hydrogeological modelling.
Extend and link existing recharge investigations across the Eyre Peninsula to assess geographic influence, as well as undertake finer-scale groundwater investigations in priority areas for exploration and potential mine development, combining local scale recharge studies linked to finer scale, targeted geophysical data acquisition (air and ground), groundwater model development and groundwater resource estimation.