A geophysical review of the Polda Basin, South Australia

Abstract

The intracratonic Polda Basin extends from the shelf edge of the Great Australian Bight nearly 400 km east to the centre of Eyre Peninsula in South Australia (Fig. 1). It is now recognised as a structural feature of some antiquity, originating as a crustal downwarp during the same Proterozoic regime that gave rise to the Officer and Amadeus Basins of central Australia. Extensive evidence of salt mobilization observed on seismic sections and confirmed by the drilling of the Mercury No. 1 and Columbia No. 1 wells supports the concept of the basin's Precambrian origins. Geophysical evidence suggests the presense of at least 5000 m of sedimentary fill, but the complete succession has yet to be drilled.