Temporal Controls on the metallogenic evolution of Western Tasmania (private)

Project overview

The exact timing of mineralisation and ore deposits formation are difficult to constrain accurately, as these deposits tend to be affected by multiple episodes of deformation and crystallisation. New techniques currently being developed now make the dating of at least some of these deposits possible. This project will use these techniques to constrain the timing of mineral growth some of the most problematic deposit in Tasmania, eastern and northern Australia to better characterise existing deposit and help with exploration for new ore resources.

Project updates

Priority deposits for geochronology

• Interview River
  • Ideally collect further Pb isotope analyses, as only one exists on this deposit.
  • Check UTAS and MRT sample inventories to see if samples are available for the Strickland Deposit, which has a very similar Mesoproterozoic Pb isotope model age to Interview River.
  • Collect a zircon U-Pb age for the Interview granite (double check that one doesn’t exist)
  • Date minerals such as monazite to constrain age of mineralisation
  • If the monazite dating confirms a Mesoproterozoic age then this is a major finding for Tasmania. A manuscript on this would then require a thorough review of the geology and tectonic evolution of Tasmania.
• Darwin South
  • This is a deposit on Mount Darwin south of Queenstown. There has been phosphates identified, small but datable.
• Henty
  • Good communication with Henty Gold Mine who plan on sending us more samples to date. Access to further samples if required should be straightforward.
  • Phosphates have been identified. This may require a bit more work, but should be doable.
• Savage River
  • Monazite date exists (~500 Ma), however many interpret this as Devonian. Need further age constraints.
• Mt Lyell
  • Very complicated paragenesis, so dating will be challenging
  • There are phosphates around, and there are some moly ages around - ~500 Ma and 492 Ma. The question is if there are multiple pulses of mineralisation. This may mean getting additional samples, either by visiting the mine or raiding the UTas collection (there should be material David Huston and Ollie Raymond collected). This could require the most effort.

Map of samples collected for AMICS

Sample summary