Case study Collaboration building Geoscience Australias Isotopic Atlas of Australia

Ongoing collaboration between Geoscience Australia and a wide range of agencies and institutions is building a nationally valuable database of geochronology and isotopes.

A good example has been the significant addition of 890 geochronology results from Victoria in 2021.

The 2021 Victorian additions were a major step in expanding the coverage of geochronology and isotopes from northern Australia to the southern and eastern states. The Atlas now boasts more than 5,000 geochronology results and 10,000 isotope results.

The Victorian data were compiled by the Geological Survey of Victoria (GSV) from an extensive search of the published literature and unpublished research.

Additional age information

The compilation was supplemented by additional age information collated by Geoscience Australia during the Stavely Project, a collaborative GA-GSV stratigraphic drilling and precompetitive geoscience project conducted in 201317 to address the challenges of greenfields mineral exploration of the Stavely Arc, located in western Victoria. Watch a video on the Stavely Arc (39:41 min).

The importance of geochronology in understanding our continent and its geological and ore-forming processes is well understood. Isotopes, which are the foundation of geochronology, are also an increasingly valuable tool for mineral and energy exploration.

Isotope studies by Geoscience Australia also highlighted a previously unrecognised break in the Earths crust in the Carpentaria Zinc Belt in northwest Queensland and the NT, which led to breakthrough research on sediment-hosted base metal deposits.

The geochronology and isotopes data have 4 major layers:

• Geochronology and age maps
• Samarium-Neodymium isotopic analyses of magmatic rocks
• Lutetium-Hafnium isotopic analyses on zircons from a range of rock types
• Lead-Lead isotopic analyses of sulphide minerals.