In desert regions, various topographies are formed by the erosional. and depositional activities carried out by the winds. Through the activities of transportation, corrasion and attrition, winds cut and sort the rocks and carry the rock particles, depositing them at other places due to which various topographies are formed in desert regions by these erosional and depositional activities of winds.
Following is the description of these topographies:
1. Erosional Topographies:
(a) Blow out: Those troughs which are formed by loose and disorganized terrain or rock parts blown and carried away by the wind are known as blow outs.
(b) Inselberge: These are projected dunes of solid rocks in the desert-like large seas, and they appear to be like an island or a mountain.
(c) Mushroom Rock: These are residual parts of solid rocks which resemble an umbrella in shape.
(d) Demoisells: Those surface columns in deserts which are protected with cover of solid rocks or terrain are known as demoisells.
(e) Driekanter Rock: A Dreikanter rock is a type of ventifact that typically forms in desert or periglacial environments due to the abrasive action of blowing wind.
(f) Stone Lattice: This is a reticulated rock which is formed by the process of corrasion by the wind upon rocks with different compositions.
(g) Zeugen: These are gorges formed by erosion of wind in the layers of hard and soft rocks spread alternately in horizontal form.
(h) Yardang: These are pointed, earth – shaped structures formed by respective vertical layers of hard and soft rocks.
2. Depositicfnal Topographies:
(a) Sand Dunes: These are small moving piles or mounds of sand, which get transported along with the wind.
(b) Ripples: These are land forms which emerge on sandy surface of the desert just like oceanic waves.
(c) Sand Drifts: These are vertically moving guilds of sand, situated on the edge of topographical obstruction.
(d) Sand Levees: These are vertical guilds of sand with a broad peak.
(e) Loess: Deposit of very fine dust particles brought by blowing wind is known as loess.
These depositional topographies formed by wind in arid regions are depicted with the help of the following diagrams.
