Surface winds are responsible for the two main types of feature observed on the Antarctic plateau: (a) sastrugi, produced by katabatic (gravity) winds, and (b) snow dunes, which are raised by blizzard winds. The two are often associated in the sense that the severest patches of sastrugi seem to be eroded out of dunes deposited by a previous blizzard. However, sastrugi are by no means limited to this; they may occur more or less continuously, merging one into the next over a wide area of plateau.

The cause of the phenomenally high winds recorded by Sir Douglas Mawson's party at Cape Denison during the Australasian Antarctic Expedition, 1911–14 (Mawson, 1939), and by the French expedition to Port Martin in 1950–51 (Boujon, 1954) has never been satisfactorily explained. As indicated in the Table, the annual mean wind recorded at those stations, 71·1 and 64·6 km per h respectively, is about 70 per cent greater than recorded elsewhere around the coast at stations fully exposed to katabatic flow, notably Mirny and Mawson. Admittedly, the total number of coastal stations is small, considering the length of the Antarctic coastline, and one cannot exclude the possibility that similar very strong winds prevail in other places. Nevertheless, the figures for Cape Denison and Port Martin are notable, if not unique, and the question arises why this should occur on the coast of Terre Adélie.

The principal field activity of the A.N.A.R.E. party at Mawson during the 1957–58 summer was the determination of ice thickness along a section of the Antarctic plateau. In previous years the summer expeditions inland had concentrated on the survey and geology of the Prince Charles Mountains, south-east of Mawson. While this programme was continued in 1957–58 as opportunity presented, and in fact air photography of the ranges almost completed, the main I.G.Y. field effort was directed towards seismic ice-depth determinations. These were the responsibility of the Bureau of Mineral Resources, and a seismologist was seconded to the Antarctic Division, together with equipment for the purpose.The traverse made lay southwards from Mawson, following approximately the meridian 62° 08′ E. It was known from prior air reconnaissance that a south-westerly spur of the Prince Charles Mountains system cut across the route in the vicinity of lat. 73° to 74° S., but the exact location was unknown. The intention was to map this spur, then skirt it to the west and resume the seismic traverse southwards.

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