Erosion and other factors caused changes to the Grand Canyon.
The earth is constantly changing and adjusting to various factors that cause changes to different landforms. Landform types include mountains, plateaus, plains, valleys, hills, islands, buttes, mesas, canyons, caves, deltas, dunes and peninsulas. Other factors that cause change to landforms include glacial movements, volcanic eruptions and tectonic plate motion — which can result in earthquakes.
When a landmass is exposed to certain weather conditions and the rock particles of the landform begin to break down into smaller pieces, this occurrence is known as weathering. The U.S. Geological Survey (USGS) studies such changes on various landforms. Weathering is the result of winds, water and gravity on the rocks, which lead to abrasion and collapse or movement of the forms.
When a river floods or a glacier shifts and moves debris down a mountain, deposition occurs. Deposition is the transporting of collapsing or broken down debris, soil, rocks and various other substances to a different location. The depositing of these substances can occur along the length of a river, stream or hillside, and will end when the forces on them stop or recede.
According to the Environmental Engineering Dictionary, erosion is “the process whereby materials of the Earth’s crust are loosened, dissolved, or worn away and simultaneously moved from one place to another.” It is the combination of weathering and deposition. Storms, winds, rains, chemical changes in the air and river flooding contribute to sudden or gradual changes. The movements of rivers and streams, crashing of waves against sea cliffs and the deposition of sediment and rock to another location downhill or downstream are all causes of erosion.
Man, too, has changed many landforms through mining, quarrying, constructing cities, building hydroelectric dams, drilling for oil and tunneling through mountains. Although economic reasons might be the motivators behind some of these actions, which may enhance societies, acknowledging the impact is vital to recognizing all causes of change to the land.