weathering: Weathering occurs in situ (on site, with little or no movement), and should not be confused with erosion, which involves the transport of rocks and minerals by agents such as water, ice, snow, wind, waves and gravity. Weathering processes are divided into physical and chemical weathering.
erosion: Erosion happens when rocks and sediments are picked up and moved to another place by ice, water, wind or gravity. Mechanical weathering physically breaks up rock. One example is called frost action or frost shattering. ... The sediment is dropped, or deposited, in landforms.
deposition: Deposition is the processes where material being transported by a river is deposited. Deposition occurs when a river loses energy. This can be when a river enters a shallow area (this coud be when it floods and comes into contact with the flood plain) or towards its mouth where it meets another body of water.