Erosion and Deposition: Action of Wind and Waves

Erosion is the process by which surface material is removed from the Earth’s crust, primarily soil and rock debris, and the transportation of the eroded materials by natural agencies (such as water or wind) from the point where they were removed. Erosion is also the process by which soil and rock debris are primarily removed.

The most comprehensive use of the term “erosion” refers to the general wearing down and molding of all landforms on the surface of the Earth. This includes the weathering of rock while it is still in its original position, the transport of material that has been weathered, and erosion that is caused by wind action as well as fluvial, marine, and glacial processes. This comprehensive definition, which takes into account mass-movement processes, is more accurately referred to as denudation or degradation. The movement of eroded material by natural agents is not considered to be part of erosion according to a specific and rather limited definition of the term; nonetheless, because this occurrence is not considered, the line of demarcation between erosion and weathering is extremely blurry. Therefore, erosion includes the movement of eroded or weathered material away from the source of degradation (such as the side of a mountain or another landform), but it does not include the deposition of material at a new location. Both the geomorphic processes of wind, flowing water, and ice, as well as the complementing processes of erosion and deposition or sedimentation, are responsible for the transformation of pre-existing landforms and the formation of new landforms.

Wind erosion 

In certain arid and desert regions, the wind plays a significant role in the process of causing rocks to erode as a result of the movement of sand. Furthermore, the surface of sand dunes that are not held together and protected by vegetation is susceptible to erosion and change as a result of the drifting of blown sand. This activity causes the material to erode by the process of deflation, which is the removal of small loose particles, and through the sandblasting of landforms by debris that is transported by wind. After repeated deflation of loose particles from landforms, bigger particles that are more resistant to deflation are left behind in the landscape. Either turbulent flow, in which particles move in all directions, or laminar flow, in which particles move in one direction only, might be responsible for the transport of eroded material caused by wind activity above or along the surface of the Earth (in which adjacent sheets of air slip past one another). The movement of material that has been eroded by wind continues until either the speed of the wind is unable to support the size of the particle that is being transported or until the particles that are being carried by the wind collide with or cling to a surface feature.

Glacial erosion

Glacial erosion can take place in one of two primary ways: either through the abrasion of surface materials as the ice grinds over the ground (with a large portion of the abrasive action being attributed to the debris embedded in the ice along the base of the glacier), or through the quarrying or plucking of rock from the glacier bed. The material that has been eroded is carried until it is deposited or until the glacier melts, whichever comes first.

Erosion caused by water

Moving water is the most significant natural agent that contributes to erosion. The disintegration or degradation of sea cliffs can be partially attributed to the activity of atmospheric agents such as precipitation, frost, and tidal scour, in addition to the action of sea waves, which are the primary cause of coastal erosion. Coastal erosion is also known as beach deterioration. Coastal erosion is caused primarily by hydraulic pressure, the impact of waves striking the shore, and the abrasion (wearing, grinding, or rubbing away by friction) of sand and pebbles that are constantly stirred by the water. These three factors work together to wear away at the coastline (see wave-cut platform). Breakwaters and moles are two examples of man-made coastal features that are particularly vulnerable to the destructive effects of wave impact and hydraulic action. The force of impact and the hydraulic action of storm waves are particularly important on coasts that are made up of heavily jointed or bedded rock. These shores are susceptible to the quarrying, which is the hydraulic plucking of blocks of rock. The most significant form of wave erosion is most likely the abrasive influence that sand and stones have when they are washed up against shorelines. Wave motion drags particles back and forth, abrasively wearing away at the bedrock along the shore and abrasively wearing away at each other, gradually reducing pebbles to the consistency of sand. Erosion caused by waves produces shorelines that are retrograde, which means they are retreating. These shorelines have sea cliffs, wave-cut benches at the base of the sea cliffs, and sea arches. Sea arches are curved or rectangularly shaped archways that are the result of different rates of erosion caused by varied bedrock resistance.

Conclusion 

Erosion is the wearing down and molding of all landforms on the surface of the Earth. This includes the weathering of rock while it is still in its original position. It also includes the transport of material that has been weathered, and that is caused by wind action. Moving water is the most significant natural agent that contributes to erosion. The disintegration or degradation of sea cliffs can be partially attributed to the activity of atmospheric agents such as precipitation, frost, and tidal scour.

Coastal erosion is also known as beach deterioration. It is caused primarily by hydraulic pressure, the impact of waves, and the abrasion of sand and pebbles. Breakwaters and moles are two examples of man-made features that are particularly vulnerable to the destructive effects of wave impact.