Some of the important landforms are Blow outs, Pedestal rock, Ventifacts, Windows and arches and Desert pavement

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By the processes of erosion, wind forms a num of landforms typical of deserts and semideserts. Some of the import landforms are given below.

(i) Blow outs:

Blow outs are small scale depressions produced bj deflation of weathered materials. They are more common in areas oi sand accummulation. The intermontaine depressions within sand hill are similar features.

(ii) Pedestal rock:

These are pillar like rock masses with narrow base and wide rock caps Pinnacles are similar features with less prominent cap rock. These are produced by combined action of weathering, gravity and wind abrasion. However, it is the wind abrasion which is Pedestal rock mainly responsible for the formation of this pillar - like structures.

(iii) Ventifacts:

These are faceted and angular rock fragments, also know as dreikanter. Wind blowing in a particular direction, produc smooth and flat surfaces.

(iv) Windows and arches:

These are features formed by the combined action of weathering, gravity, wind, ground water a running water. The surface forms are like arches which act natural bridges.

(v) Bowls and caves:

These are commonly seen in areas of calcareous sandstones, where calcium carbonate is dissolved by chemical weathering; sand grains are disintegrated and are blown out by wind, forming bowl and cave like features.

(vi) Desert pavement:

In deserts and semi-deserts, the dust and finer particles of the weathered rocks are blown out by the wind, and heavier pebbles and rock fragments are left out. After long exposure to wind, the fragments and pebbles become finely polished. This type of land surface is termed as desert pavement which is like a sea broken rocks. They are lag deposits. The areas with large sized rock fragments are termed as hammadas.


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