The National Argon Map

The National Argon Map (NAM) project is an AuScope 2020 Pilot Project led by Dr Marnie Forster at the Australian National University and overseen by an independent advisory panel that is led by Dr Geoff Fraser of Geoscience Australia. It is being developed in collaboration with the National Argon Network, involving the Argon laboratories at the Australian National University, Curtin University, the University of Queensland and Melbourne University. The data registry is visualised in the map above. AuScope supports the cost of Ar/Ar analysis in this Pilot Project. Our Purpose: This AuScope pilot project is supporting the addition of vital new Ar/Ar geochronology data to the existing legacy data based Geoscience Australia NAM (seen above). The aim is to build on the NAM, to ‘fill the gaps’ in this isotopic map, to undertake Ar/Ar geochronology in areas that have as yet no data, or areas where important information is missing, or new techniques bring new information. Why Ar/Ar?: Ar/Ar can produce age data from diverse geological scenarios. A wide range of different minerals can be used, e.g., white mica, biotite, different feldspars, horneblende, phlogopite, basalts, alunite, sericite, and less commonly minerals like glaucoophane, pyroxene, tourmaline, stilpnomelane, volcanic glass etc. Ar/Ar can date the very young to the very old, from thousands to billions of years ago, in events that range from new growth, recrystallisation, metamorphism, deformation, and alteration (caused by heat, fluids, mineralisation) linking into mineral resource exploration. In particular the NAM will allow the linking of existing high-temperature geochronology (U–Pb or Hf) maps to low-temperature (FT, U-Th/He) geochronology maps, providing an important infrastructure base required to allow unraveling of time in the Australian geological architecture.

How to be involved: If you have a project where Ar/Ar would provide vital information that is suitable for the NAM, then email Marnie or Geoff (Emails: Geoff.Fraser@ga.gov.au; Marnie.Forster@anu.edu. au) and talk to them about your ideas and possibilities. Entry to the program is by submission of a Project Proposal to the Advisory Panel, who review the submissions. If accepted samples will go to one of the participating Argon Laboratories. Since mineral separation is vital for meaningful results, once your proposal is accepted, talk to Marnie before you undertake the mineral separations. AuScope only supports the cost of Ar/Ar analysis.

To submit samples for analysis in the NAM please download this  Data Acquisition Project Proposal Form.pdf and submit to Geoff.Fraser@ga.gov.au. All proposals are reviewed by the NAM Oversight Panel. Accepted proposals will have their Ar/Ar samples analysed with the financial support from AuScope. The NAM Project Proposal in linked here. Please email or ring Marnie to discuss details or if you have questions - Marnie.Forster@anu.edu.au.