Why Aeolian Erosional Process produces Landforms in Arid Region

Why Aeolian Erosional Process produces Landforms in Arid Region

Posted by Manisha on May 19, 2020

The place which has no vegetation or sparse vegetation and receives low rainfall around less than 15 cm per year, also sometimes no rainfall, becomes arid (dry) popularly known as desert.
The roots of plants weave into each other which bind the soil into it and save from erosion, but in the absence of plants and water, the wind became active over this area. Naked land easily eroded by wind resulted in the building of Aeolian Erosional Landforms in this arid region.

8 Erosional Landforms produced by Wind

Here are eight Aeolian Erosional Landforms of the arid region as follows:

1. Blow-outs or Deflation Basin or Hollows

  • It is a major depression on the surface of land when the wind has blown away the loose sand or topsoil.
  • This is formed due to the deflation process of wind erosion on bare land, (sparse vegetation and uncemented) surface in the arid region. 
  • These are enclosed depression’s caused by wind erosion.
  • This landform mostly forms in the Tropical desert region and Coastal areas.
  • When the fast wind blows from the sparse vegetation or naked land, which is full of loose sand and uncemented surface, and sediments it formed Eddies (winds circular motion over an area) erodes away the loose lands along with them and creat depression.

  • This depression slowly-slowly gets more eroded and converted into big hollows or depression.
  • These hollows also named deflation basins and Blow-out.
  • This bow-outs size may increase up to around 14 km long, 8 km wide, and 100 meters deep. 
  • Sometimes these deflation hollows reached the groundwater level.

For example, Wyoming Big hollow of U.S.A.

2. Mushroom Rocks or Pedestal Rock

  • As its name implies, it resembles a mushroom that’s why it is named the Mushroom rocks also known as Pedestal rocks.
  • It is formed when the transported material with wind erodes away the soft rocks, from the big rocks, where hard rocks are overlying soft rocks, similarly as the pattern of waterfall rocks.
  • The wind blows the light sand particles on more height whereas the heavyweight sand granules creep along with the ground and as we know small sand particles did less erosion than the heavy sand granules which results in the more erosion of rocks on its pedestal area than the upper area of rocks, lastly we found a mushroom rock.
  • It named as different names in different regions like Hamada in Sahara desert, Gara in the Arabic language.

Some examples of Mushroom rocks are: Timna park-Negev, Israel, Mushroom rocks are also found in Egypt.

3. Inselberg or Monadnock

  • The origin of the word Inselberg is from two German words are Insel + Berg which means island + mountain. 
    So, the literal meaning of inselberg is it is an isolated hill or mount which looks like an island, rising abruptly from a plain.

  • It is an isolated rock hill, knob, ridge, or small mountain-like huge or small rocks that is gently sloping and has a smooth surface.
  • The shape of all inselberg depended upon the structure of rocks.
  • Granite rocks inselberg looks like a semi-circular rocks and sandstone inselberg looks like big pillars.
  • Commonly found in Kalahari, Sahara, North Nigeria, Algeria deserts.

4. Demoiselles or Earth pillars or Hoodoo

  • These are pillars like landforms.
  • It is formed when wind erodes all the soft rocks situated all around the hard rocks. Only the rock which is situated just below the hard rock, left behind which resulted in pillars like structure.
  • It is looked like a set of narrowly tapered rock columns, which is topped with a large hard rock, balanced neatly on a tip.
  • In some areas, it is also known as Hoodoos.

For example, Pontis of France, Alpes-de-haute-Provence.

5. Zeugen

  • It is a tabular landform in which a layer of soft rocks lying beneath a surface of a layer of hard rocks.
  • When a layer of hard and resistance rocks spread over a soft rock horizontally. Wind abrasion erosion carves them into the furrow landscape.
  • The mechanical weathering and wind erosion together lead to the formation of Zeugen.
  • A tabular mass of resistant rock up to 100 feet high, standing out from softer underlying rocks because of its protective capping.
  • It is produced by differential erosion in a desert through the scouring effect of sand-laden winds.
  • It may stand 10-100 feet high.

6. Yardang

  • These also look like Zeugen but are different.
  • In this the rocks are positioned vertically which means hard rocks stand vertically each after the soft vertical rocks.
  • Yardang is formed when the soft vertical rocks were eroded (fully) by wind and hard vertical rocks were partially eroded.
  • These partially eroded hard vertical rocks are known as Yardang.

7. Dreikanter or Ventifacts

  • The word dreikanter is derived from a German word, which means three-edged.
  • It is a type of Ventifact that is why also called Ventifacts.
  • It is a three-faced pebble that is polished and flattened by wind abrasion erosion.
  • It is formed due to weathering when big hard rocks weathered and small pieces of weathered rocks fall on the sand surface. Here the work of wind begins and the wind starts polishing and shaping it. Then these piece of rock is known as Dreikanter.

Found in Algeria, Libya, etc.

8. Stone Lattice

  • When the wind erodes the soft portion within the rocks through the abrasion which resulted in small-small pits on the surface of rocks.
  • Then the rocks with a pitted and fluted surface are called Stone Lattice.

I never got a chance to tour the arid region or desert closely yet. But, if you ever had any tour in such an area or place, then share your precious experience, story, and photos. What did you like the most among them?

If not then now after reading this post are you able to relate yourself with them?
And the readers who do not experience any place visit and landforms in reality yet, would you like to share your understanding about the features and landforms? 
Write to me with your inspiring, motivating, and precious words.