The geology of the area east of Point Pass, South Australia

Abstract

The elevated range east of Point Pass is defined by a sequence of 3,650 metres of Late Pre-Cambrian glacial and post-glacial sediments. The glacial sequence is composed of 1,850 metres of pebbly tillite and bedded arenaceous interglacials, which unconformably overlie the laminated Saddleworth Siltstones. The 1,800 metres of sediment conformably overlying the glacial sequence are generally composed of calcareous and non-calcareous argillites and feld­sarenites which have been deposited under a shallow sea in the slowly subsiding Adelaide Geosynclinal Basin. Major block-faulting has resulted in the truncation and subsequent disappearance of the upper beds of the Tarcowie Siltstone, which represents the youngest Pre-Cambrian sediments exposed in the area.