Oral Presentation Australasian Groundwater Conference 2017

3D modelling of aquifers provides a visual representation of well data typically stored in a database. A 3D interactive model containing one or many aquifers can be produced that is excellent tool for demonstrating and explaining hydrogeological features to both technical and non-technical people.

The 3D groundwater features are constructed using existing drillhole information stored in the SA drillhole database. In particular the elevations of hydrogeological features are used to interpolate elevation surfaces, such as the top and bottom of various hydrostratigraphic formations. 

Known hydrogeological features for resource regions in South Australia have been constructed in ArcGIS in conjunction with the ANU DEM algorithm and the Arc Hydro Groundwater Toolkit. The resulting 3D model features are hosted in the readily accessible Adobe PDF Reader, in an interactive environment where users can rotate, zoom, apply vertical exaggeration, and make cross sections.

Not only is the 3D aquifer modelling a powerful visualisation and demonstration tool, but we have been able to demonstrate several spin-off benefits from the end product, and from the process involved in the 3D modelling itself which can also add further value to existing data thereby enabling more comprehensive aquifer assessments.

Examples include:

• The capability to assign aquifers to wells that have depth or production zone information but no geological log.
• Collating water level and salinity data from wells, from which 3D water level features for aquifers can be created and used to determine areas of confinement and leakage potential.
• Improving interpretation of aquifer extents and the discovery of new hydrostratigraphic features and structures.
• Development of tools for managing groundwater resources (salinity management, recharge estimates, waterlogging assessment, storage volume calculations).