New data, new insights into the Tasmanian cover

Tasmania's extensive Jurassic dolerite and Cenozoic basalt cover and the nature of their physical properties have effectively confined mineral exploration to the west and north-east of the State. Largely as a consequence, precompetitive geophysical data acquisition has concentrated around those regions. In recent years a number of factors have changed this situation. The advent of passive seismic and magnetotelluric techniques have demonstrated ability to identify features beneath the Tasmanian cover that can be connected with geological structures known to have tectonic and possibly metallogenic significance. Additionally, the cover itself has become thought of an exploration target for bauxite, rare earths and most recently natural hydrogen. Two airborne magnetic and radiometric surveys over a major portion of Tasmania's covered terranes have now been added to the State's existing coverage. In addition to very effective mapping of geological units and structures within Permian to Cenozoic cover sequences, the new data in combination with deeper-penetrating passive methods suggest relationships of cover structures to fundamental basement features.