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The destructive force of the wind consists in the blowing away of fine eluvial material, or in the grinding of rock surface by the sand carried by the wind. Only in exceptional situations can strong winds tear off small fragments of brittle rocks. The hitting with fine particles of sand carried by the wind can damage even hard rocks. However, this process is very slow. Therefore, above all, the transporting and building forces of the wind play a huge role in the shaping of terrain. When blowing almost incessantly, the wind is able to carry and lay off, in other places, large amounts of tiny grains of rock. However, in order for these processes to take place, the following factors should occur at the same time:

• the wind must be strong enough;

• the rocks in the substrate must be heavily disintegrated;

• the substrate must not be wet or covered with abundant vegetation.

For most of the day, and almost the entire year round, these conditions are fulfilled in deserts, and it is there that the ‘sculpting’ activity of the wind manifests itself most strongly. Hot deserts exist mainly in high atmospheric pressure areas in tropical zones, where atmospheric circulation causes extremely low rainfall. Deserts are also formed in subtropical and temperate zones in areas where distance from water bodies and the lay of the land contribute to the creation of extremely continental characteristics of the climate and the associated low rainfall. Depending on the nature of the substrate, there are three main types of deserts:

• ergergerg (sand desert),

• serirserirserir (gravel desert),

• hamadahamadahamada (rock desert).

Wind also transforms the Earth’s surface on the sandy coasts of seas and oceans, on plowed farmland, in open‑pit mines, and on the forelands of glaciers and ice sheets, but only if the surface layer of soil and eluvium is dry. The processes associated with the activity of the wind are called eolian processeseolian processeseolian processes.

Depending on the speed, wind can lift larger or smaller grains of sand and dust. Maybe these grains hit the rocks and slowly grind, groove, smoothen and scratch. This process is called a corrasioncorrasioncorrasion. The closer to the Earth's surface, the more the sand is raised by the wind, and the process of corrasion is stronger. Therefore, rocks protruding above the desert surface are subject to the greatest damage in their lower part. As a result, various, sometimes very fanciful, rock forms are created. Rock fungi are rocks, which in the upper part are wider than in the lower part.

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Ilustracja przedstawia Arbol de piedra, skalną formacje - grzybka skalnego, znajdującego się w Altiplano w Boliwii. Forma skalna wyrasta na pustyni - została uformowana przez wiejące w tym terenie wiatry, które niosąc piasek rzeźbią kształt skał. W tle skaliste wzniesienia.

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Ilustracja przedstawia Skałki Grzybowe, znajdujące się w Yehliu Geopark w Tajwanie. Te formacje skalne powstały w wyniku szybszej erozji mniej trwałych skał z niższej warstwy wolniejszej erozji twardszych skał wierzchnich. Twardsze skały maja ciemniejszy kolor i dlatego wraz ze swoim kształtem przypominają kapelusze grzybów. W górnej części zdjęcia morze.

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Ilustracja przedstawia skalnego grzybka, znajdującego się w Mushroom Rock State Park w Kansas w USA. Ta formacja skalna stoi wśród wyschniętych traw. W tle las.

Keywords

erg, hamada, eolian processes, serir

Glossary