Recent models for the tectonic development of the Tasman Fold Belt postulate oroclinal bending as the mechanism for formation of arcuate geological features in eastern Australia. In Tasmania, rocks of the mid Palaeozoic Dundas- Fossey Trough appear to ‘wrap around’ the Neoproterozoic Tyennan block and this feature has been interpreted as a possible orocline.

Kathryn’s Honours project involved palaeomagnetic analysis of samples collected from Ordovician and Silurian sedimentary strata from around the proposed Dundas-Fossey orocline to test the validity of this model. Palaeomagnetic measurements were supervised by Dr Bob Musgrave (GSNSW) and were conducted in the palaeomagnetic laboratory at the University of Newcastle. Approximately 60% of sites gave credible estimates of the original primary magnetisation direction. Magnetisation vectors are aligned in an approximately north-south orientation in western Tasmania and approximately east-west near Mole Creek in northern Tasmania. Statistical analysis of these data potentially supports the oroclinal bending model but unfortunately samples in critical locations such as the hinge of the proposed fold and on the eastern limb did not provide primary magnetisation estimates. A paper outlining the results of this investigation has been submitted to the Australian Journal of Earth Sciences. Additional palaeomagnetic sampling will be undertaken in 2018 to infill Kathryn’s sample distribution and hopefully assess the validity of the proposed oroclinal model for Tasmania.