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The late Neoproterozoic (ca 600 Ma) Whyalla Sandstone covers 25000 km(2) in outcrop and subcrop on the Stuart Shelf, South Australia, and is coeval with the Marinoan glaciogenic succession in the adjacent Adelaide Fold Belt. The flat-lying formation is up to 165 m thick and comprises mainly reddish brown, medium- to very coarse-grained, weil-rounded, commonly bimodal quartzose sandstone that shows regional south-southeastward fining, Low-angle (less than or equal to 15 degrees) strata form the principal stratification type. Large-scale cross-bedded sets up to 7 m thick occur mainly in the central area; cross-strata usually have dips of less than or equal to 20-23 degrees and rarely up to 30 degrees, and display grainfall and grainflow deposits, inversely graded subcritically climbing translatent strata, and `pin stripe lamination’. Periglacial cryogenic structures in the basal 5 m of the formation include two generations of primary sand wedges, drop involutions, periglacial injections, frost-heaved blocks, water-escape structures, and thermokarst microtopography. Small-scale tensional faults suggest collapse caused by snow melt, The sedimentary features of the Whyalla Sandstone together indicate an aeolian origin and the periglacial structures imply a cold, arid and strongly seasonal climate. The preponderance of low-angle strata accords with a periglacial sand-sheet environment, with dune forms confined mostly near the centre of the sand sheet, Cross-bedding attitudes and the direction of regional fining, together with palaeolatitudes inferred from palaeomagnetic data for Marinoan glaciogenic strata in the Adelaide Fold Belt, imply the movement of cold, dry palaeowinds obliquely toward or across the palaeoequator during the Marinoan glaciation.