Weathering and erosion. Weathering breaks the rock and erosion moves the rock. when rock is broken down it is moved by water or other substances. When the erosional agent looses its ability to move the load ( Eroded Rock) then deposition happens which creates a sediment over time. hope this helps
what weathering does is that weathering moves your soil or sediments and then when it hits a stream erosion happens and moves it down along the stream and then comes deposition and the sediment lands at a random spot.