At the start of the sedimentary cycle we find erosion. The agents of erosion (wind, rain, freezing) tear away fine particles or whole fragments from rocks. Once torn away, these materials are displaced by the agents of transport (glaciers, wind, water). Gravity plays a primary role in this process.
When transport is carried out by water, we speak of fluvial or marine transport.
The greater the speed of flowing water, the greater its capacity to transport materials is. On reaching a plain, then in lakes or oceans, the rate of flow slows down and sediments become immobile, and accumulate.
One river can transport up to 10 million tons of sediment per year.
Erosion – transport – accumulation: these are the three links in the chain of the sedimentary cycle.