Deposition is the process by which eroded material is deposited elsewhere. As seen in the pictures, deposition often occurs close to where erosion took place, such as material from slumping or creeping slowly moving down a hill under gravity. Deposition forms features like deltas at the mouths of rivers, where sediment is dropped as the fast-moving water slows upon reaching the sea. Over long periods of time, the repetitive natural cycles of weathering, erosion and deposition can dramatically transform entire landscapes through processes like cave formation and glacial deposition.