Pandurra Formation crops out in a broad belt extending 230 km NW from Whyalla and near Pernatty Lagoon and is present in the subsurface for a further 200 km to the NW. Possible equivalents exist on Eyre Peninsula and near Lake Frome. It comprises fluvial redbeds, sandstone, siltstone, shale and pebbly sandstone interbeds. Four members are recognised, including a distinctive red-brown siltstone-shale interval in the lower part, and a member characterised by cyclic deposition in the upper part. The persistence of this subdivision irrespective of the depth to underlying basement indicates that the Pandurra Formation was probably not deposited into a graben as previously believed. Instead, the present half-graben morphology is a result of later faulting largely confined to the NE and eastern margins near Olympic Dam and Port Augusta. Limited sedimentological work indicates a braided-stream origin, with indications of alluvial fan, aeolian, deltaic and lacustrine influences. Copper mineralization is prominent in the upper part of the Pandurra Formation near Pernatty Lagoon, and includes the Cattlegrid deposit. Potential for placer gold and redox uranium deposits has not been fully evaluated.