Sastrugi breaking equipment—ripples and waves are often undercut and the surface is hard and unforgiving, with constant minor topographic changes between ridge and trough. The words "sastrugi" and "zastrugi" are Russian-language plurals; the singular is "sastruga" or "zastruga". The form "sastruga" started as the German-language transliteration of the Russian word заструга (plural: заструги). A Latin-type analogica singular "sastrugus" is used in various writings on exploration of the South Pole, including Robert Falcon Scott's expedition's diaries and Ernest Shackleton's "The Heart of the Antarctic". Under the action of steady wind, free snow particles accumulate and drift like the sand grains in barchan
Surface features of Venus parabolic excavation cones and flows of lava-like debris. Recent Magellan images show over 6000 aeolian landforms, including dunes (or "undae"), wind streaks, and yardangs. Undae and yardangs have direct analogues on Earth and the process that creates them here can be applied to those seen on Venus. Large dune fields have been identified on the surface and the dunes range in size from meters to hundreds of meters. Similarly, yardang fields may exist in locations such as Mead crater. Wind streaks are parallel linear streaks that form as prevailing winds erode the surface geology. These features illustrate the erosive effect