The Adelaide Geosyncline: A Century of Controversy

Late Proterozoic (Adelaidean) to Late Cambrian sediments of the Adelaide Geosyncline form a mountainous backbone to South Australia. Geological studies of the region date back to the beginning of European exploration and colonisation, although these were limited until the 1940s due to the small, isolated nature of the geological community. No detailed understanding of this extensive region emerged until the beginning of the twentieth century when sections were measured and the significance of widespread Late Precambrian glaciation was recognised. The search for fossils has been long and often unsuccessful. Trilobites and archaeocyatha, which were later determined as Cambrian, were found as early as 1879. The internationally famous Ediacara fauna was discovered in 1946. Unusual piercement structures containing breccias were only widely mapped after World War Two with a diapiric origin being proposed in 1960. In 1952, the province was classified as basically miogeo-synclinal with a late stage eugeosyncline in the southeast. This has recently been reinterpreted in terms of plate tectonics.