Deposition a consequence of geographical erosion. Erosion is the removal of soil, rock or sediment from the landscape. Three processes take place during erosion: detachment, entrainment and transport remove the material from the land. Deposition occurs when that material settles in a new area.
Erosion begins when particles detach from the surrounding material. The particles are then lifted during the entrainment process. It is difficult to distinguish between the detachment and entrainment phases. Entrained particles are then transported if velocities are great enough to overcome the force of the gravity on the mass and carry the particles vertically.
Deposition on Land
Typically, erosion occurs from repeated cycles of entrainment, transport and deposition. Deposition, like transport, is dependent on the velocity and resistance of the particles. Wind, water and surrounding obstructions affect the velocity. Lower velocities increase the probably of deposition under most conditions. Increases in resistance of the particles also increase the likelihood of deposition. Temperatures effect air pressure and wind, contributing to deposition as well.
Deposition in Water
The velocity of water is affected by changes in streams and presence of ice. Particles in bodies of water can be deposited due to the chemical processes, precipitation and flocculation. Precipitation occurs when salts solidify due to physical and chemical changes in the water. Flocculation happens when salts cause particles to collect into larger masses that sink in the water.
Example of Deposition
Deposition occurs when waves wash sand, rock and pebbles from the sea floor to the beach. In this case, deposition is likely to occur if the waves enter shallow water or a sheltered area, if there is little wind and a good supply of material.