The Lower Cambrian, Puttapa Syncline, Flinders Ranges, South Australia

Abstract

Unconformities are now recognized above, below and within the Uratanna Formation. Considerable erosion, to the base of the Rawnsley Quartzite Member, occurred before the deposition of massive quartzites, with interbeds of shale. Further channelling of these sediments to a stratigraphic level below that of the Ediacaran Fauna occurred before the deposition of drab green siltstones and shales. The upper unit is assigned a Cambrian age on the basis of trace fossils but the age of the lower unit is uncertain. A more widespread shallow marine transgression is evidenced by the Parachilna Formation. Thick carbonates of somewhat different facies from nearby areas, developed within a deepening sea. The regression of the Lower Cambrian sea is not recorded within this area and the age of the youngest beds of the Parara Limestone is uncertain.