Knowledge gaps in the conceptualisation of surface water and groundwater systems of the Galilee subregion include:

  • Influence of geological structural features (e.g. Barcaldine ridge, major faults) on regional groundwater flow in the Galilee Basin, for example, is there compartmentalisation in the aquifers?
  • Refined understanding of structural geology, lithological variations, aquifer compartmentalisation and distribution of rock properties such as porosity and hydraulic conductivity on a regional scale would assist in understanding the dynamics of deep groundwater systems in the Galilee Basin. This would improve understanding of groundwater fluxes between the Galilee and overlying sedimentary basins.
  • Influence of landscape processes and evolution on groundwater systems in the Galilee Basin. For instance, did incision of the Carmichael River result in the westward migration of the north-trending groundwater divide that affects some of the groundwater systems in the Galilee Basin?
  • There is limited groundwater quality and isotopic data for groundwater systems in the Galilee Basin. These data would aid in better understanding connective groundwater pathways and groundwater fluxes between aquifers.
  • The extent of connectivity between Cenozoic aquifers and deeper groundwater systems such as regional aquifers in the Eromanga Basin would assist in quantifying how much groundwater moves between the various aquifer systems and what bearing this may have on groundwater – surface water interactions.
  • The stratigraphy of the upper Permian coal measures is in the process of being revised by Phillips et al. (2016). Some consideration should be given to incorporating the new stratigraphic subdivisions as outlined by Phillips et al. (2016) into future reiterations of the Galilee subregion geological model. Also, potentiometric mapping should be reviewed in light of new stratigraphic understandings. This may in turn improve hydrogeological understanding of the upper Permian coal measures.
  • Quantification of surface water – groundwater interactions in the Galilee subregion. Very little is known about them. This would assist in management of water-dependent assets. This could include mapping areas where river systems could be interacting with groundwater systems (either as gaining or losing streams).
  • Diffuse recharge estimates for GAB aquifers are lower than what was originally estimated by Kellett et al. (2003). Studies to revaluate recharge estimates should be undertaken for GAB recharge areas. Also, the potential for episodic recharge to GAB aquifers along eastern margin of the Eromanga Basin is poorly known. It may be an important component for water balance, as is the case along the western margin of Eromanga Basin.
  • Long-term groundwater time-series water level data for aquifers in Galilee Basin, as well as more groundwater quality data (especially salinity) would improve understanding of groundwater systems and the conversion of drill-stem test pressure data to equivalent hydraulic head.
  • There is limited information on the variability and extent of baseflow for rivers in the Galilee subregion. Although Section 2.1.5 in companion product 2.1-2.2 for the Galilee subregion (Evans et al., 2018) provides an initial estimate of possible baseflow for two major river reaches, estimates could be refined if some of the data gaps outlined in Section 2.1.5 were addressed.
  • More stream gauge and surface water quality data would allow for better characterisation of the surface water systems.
  • More detailed understanding is needed about the volume of discharge at springs and its relationship to groundwater pressures in the vicinity of spring vents.

Further discussion on gaps and opportunities for future work are also outlined in Section 3.7 in companion product 3-4 for the Galilee subregion (Lewis et al., 2018).

Last updated:
17 December 2018