Theory question 203
Wind and Desert LandformsWith the aid of diagrams describe the characteristics and mode of formation of any two of the following (a) Yardang (b) Crater (c) Block mountain
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Yardang: ridges of hard rock separated by grooves, parallel to the prevailing wind, 5-15 m high, in deserts (Atacama, Central Asia); formed where vertical bands of hard and soft rock lie in the wind direction and sand-laden wind scours the soft bands.
Crater: funnel-shaped hollow at the top of a volcano; formed when the volcano explodes and material is blown out of the vent, or the summit collapses; may fill with water to form a crater lake.
Block mountain (horst): uplifted block with steep sides and flat top, bounded by parallel faults (e.g. Ruwenzori, Vosges, Black Forest); formed by tension or compression in the crust: the middle block is pushed up or the outer blocks sink along faults.
Each with a labelled diagram.
Choose two and draw a labelled diagram for each.