Although we don't always perceive it directly, the terrain relief is very dynamic and is always changing. Some of these transformations can be more easily visualized, such as erosions; others are longer and take thousands of years to happen, such as the formation of mountains.
These transformations happen thanks to the agents of relief transformation, which are elements responsible for the alterations and constructions of the forms that we observe on the Earth's surface. So, to better understand these agents, they were divided into internal or endogenous agents and external or exogenous agents.
Youinternal or endogenous agentsRelief transformation factors are those that arise or act from within the Earth, that is, below the surface. These are earthquakes, volcanism and tectonism.
You external or exogenous agents, on the other hand, are those that act above the relief, that is, on the surface. These are the actions of winds, waters, weathering and living beings.
Endogenous agents act thanks to the forces exerted by the movement of the earth's magma, which moves the various "pieces" that form the earth's crust, called tectonic plates. Thus, thanks to the collision and the distance between two of these plates, we have the occurrence of volcanoes and earthquakes, in addition to the formation of mountains, valleys, among other forms of relief.
Exogenous agents, on the other hand, “sculpt” the relief forms that formed and changed over time. That expression “soft water on hard stone, it hits until it pierces” expresses this issue well. For example, rainwater, when draining over the surface, “washes” the soil, removing some of its layers, which are transported to the rivers. When there is no vegetation in the place, this runoff can cause the formation of large holes, callederosions.
This rock formation was sculpted by the action of the winds
In this way, we can better understand why the relief forms that make up the surface are so varied and change over time.
By Rodolfo Alves Pena
Graduated in Geography
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