FoFluvial (river) processes work on the wetted perimeter and the river bed. Erosion acts vertically and laterally on the wetted perimeter.
The processes which change rivers are split into three categories. Erosion: The four different ways that the wetted perimeter is worn away by river flow and the materials it carries. Transportation: Four different ways that materials are moved by a river. Deposition: When material is dropped by a river as it has no energy to move the material further. |
Erosion
There are four different types of erosion.
Type of erosion |
Definition |
Attrition |
Where rocks bounce into each other and are eroded by the force of the collision |
Corrasion/ Abrasion |
Where material is eroded like sand paper as rocks move along the bottom and scrape at the ground |
Corrosion/ Solution |
Where material is eroded because the small amount of acid in the water slowly eats away at it |
Hydraulic Action (or Hydraulic Pressure) |
When water is forced inside a crack in the rock, the pressure inside the crack builds up until it gets too much and splits the crack further apart |