We explain what erosion is and what this physical process consists of. In addition, how wind erosion and water erosion are carried out.
What is erosion?
Erosion is called wear that exerts over time the different physical processes of the earth’s surface on soils , rocks and materials that could exert resistance. The main erosive agents are wind, water , ice and temperature changes.
Erosion is not equivalent to weathering, process of alteration or disintegration of rocks. For the existence of erosion, a transport of matter or a movement of the same is required, whose repeated passage generates friction and wear on the materials, producing the relief , for example, of valleys, canyons, caverns, plateaus and other structures whose formation does not The man’s hand intervenes.
However, certain human activities can lead to or even accelerate erosion . For example, logging for agricultural purposes removes the topsoil from the soil, leaving it uncovered for rain or wind, which can eventually lead to soil infertility due to nutrient loss.
In fact, under auspicious conditions, erosion can be an intense force in the desertification of soils , which would contribute to the expansion of 35% of the land area that is already considered desert.
On the other hand, the action of wind or water can produce interesting natural monuments: natural arches or peculiar rock formations, such as those that exist in the Salar de Uyuni, in Bolivia, or in the Moon Valley of San Juan, Argentina.
Erosion is the product of the constant action of the wind over the years , transporting tiny particles of sand or rock that, in constant friction against soils, stones and mountains , reduce their outer layers, carving them.
Wind erosion in desert areas is responsible for profiling sand dunes , displacing them, or forming stone deserts, called “erg”. In humid areas, on the other hand, it usually produces flat or slightly wavy reliefs, due to the transport of much finer materials, such as sedimentary clay deposits.
Water erosion is due to the action of multiple forms of water , from rain, rivers, seas and their phase changes according to weather seasons. Thus, the constant attacks of the waves on the sand of the shore reduce and round the pebbles that make up the sand, giving them their characteristic fineness and roundness, which also happens with river stones.
On the other hand, the larger rocks resist the impact of water without moving, but gradually losing particles of its outer layer, thus acquiring the roundness and smoothness that usually characterizes them, or the holes and craters in which the water drops fall incessantly. .
The cliffs, likewise, or tidal waves, are the product of the action of the sea throughout the centuries, as is the case with the riverbeds, in which soil matter is eroded and sedimented.
The same occurs in glacial regions, in which the movement of ice, or even its constant formation and melting, has an impact on the surrounding materials, also causing wear.