When we go on excursions to natural environments or when we travel by road, we come across landscapes that have been and are shaped by erosive processes. Erosion produces a modification in the surface of the earth, wearing it down and deteriorating it. There are different types of erosion, some being more aggressive than others. The types of erosion that can occur are: wind, water and gravitational, without leaving behind the erosion by anthropic action that is caused by the activities of human beings and not by natural elements like the previous ones.
In this Green Ecologist article we will focus only on one type of erosion. Specifically, we will know in more detail the wind erosion, its definition, types and examples.
What is wind erosion - simple definition
Etymologically the word aeolian is derived from "Aeolus", god of the wind. When we speak of wind erosion we refer to those deterioration or degradation processes that are given by the wind action and so modify the relief of the earth's crust.
This type of erosion is less aggressive than water erosion, it is also slow and requires soils free of vegetation so that it does not stop the erosive action of the wind. It occurs in areas with large temperature fluctuations, this helps the rocks to break and, in this way, the wind acts more effectively on them. High mountain and desert areas are affected by the wind or wind erosion, as well as areas free of vegetation, that is, bare soils. Since, if the territory were populated with vegetation, the erosive action of the wind would be slowed down by the vegetation and would be much lighter or null.
Types of wind erosion - wind processes
Wind erosion is divided into 3 stages, in which there are 2 main types of wind erosion or wind processes:
1. Erosion process
Within the erosive action they manifest two processes or types of wind erosion:
- Wind erosion by abrasion: the wind carries elements such as sand, which cuts and polishes the exposed rocky surface, generating wind patterns on the surface. This process generates some characteristic forms in the rocks which are known as ventifacts, yardangs, taffonis and fungif.webporm rocks.
- Wind erosion per defflation: the air blows and sweeps, carries or lifts the particles that are on the ground. Thus, there are three types of deflation or transport (which we explain below): saltation, suspension and rolling or drag. With this type of wind erosion, in the end the desert pavement occurs and three types of desert can be formed: Reg or stony, erg or sandy and, finally, rocky or mountainous.
2. Transportation
There are three ways in which the wind can transport the particles, one of them is drag or bearing, in which large particles from 500 to 2000 µm are transported. This saltation that transports the medium particles ranging from 100 to 500 µm and also the suspension which carries the smallest particles smaller than 100 µm.
3. Sedimentation
In this process, the particles carried by the wind fall into sand deposits called dunes. This occurs due to the loss of energy from the wind. Depending on the direction the wind is going, there is the sedimentation downwind, windward and the sedimentation that goes in the opposite direction to the windward, leeward. Learn more about this in this other article on What is sedimentation.
Examples of wind erosion: the dunes
The formation of a dune depends on the energy of the wind, the amount of sand, the presence or absence of vegetation and the direction in which the wind is heading. So they can be identified as examples of wind erosion the following types of dunes:
- Cross dunes: The areas where this type of dune is formed have a large amount of sand and the soil is absent of vegetation.
- Longitudinal dunes: this type of dune is formed parallel to the wind. They are usually large dunes. We can find them in Australia, in Africa and in the United States in Arizona and California.
- Parabolic dunes: They are characterized by forming suddenly, if we look at them from above we will see that they have an inverted "U" shape, formed by two arms that come together to form a top. It has two slopes, an internal one in the direction that the wind is going, and an external one in the opposite direction to the wind.
- Barjanes: in the formation of this type of dune the wind is directed in only one direction and the amount of sand is limited. It is shaped like a half moon, resembling satellite dishes, although in the barjanes the top moves slower than the arms. They can be found in Baja California and Sonora.
- Star dunes: As their name indicates, they are called a star dune since it is characterized by having several radial arms and the wind that forms them is constantly changing. They are found in areas with a fair amount of sand and remain fixed.
If you have found this information about wind erosion useful and you want to learn more, we recommend you enter our article on the Types of erosion that exist.
If you want to read more articles similar to Wind erosion: definition, types and examples, we recommend that you enter our category of Other environment.
