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1. State three reasons why wind erosion is predominant in desert areas
2. With aid of well labeled diagrams, describe the formation of the following desert features;
(i) Rock pedestal.
(ii) Zeugen.

Answer Text:
1. Presence of loose unconsolidated gravel/stones/ soil particles that can easily be picked by wind
- Presence of little or no vegetation on the surface of desert
- Presence of strong prevailing winds in deserts
2. i) - Rock outcrops with alternate layers of hard and soft layers project above the surface
- The softer rocks are eroded by abrasion faster than the hard rock. They are worn out more rapidly than resistant ones. This results in an irregular rock with protruding layers that alternate with hollows called pedestal

ii) -First there is a landscape with horizontal alternating layers of hard and soft rocks.
- Weathering opens joints and cracks on the top resistant layer.
- Abrasion erodes the opened joints while deflation carries away the eroded materials.
- The process continues and with time causes a ridge and furrow landscape to develop.
- The ridges are zeugens while the furrows are yardangs.