UPPER COURSE:
Erosion
River erosion is the wearing away of the land as the water flows past banks. The four main types of erosion are:
* Abrasion: scraping away of the river bed and banks, this occurs when the materials that are carried by the river.
* Solution: chemicals in the river that dissolve minerals from the bank, carrying them away in solution.
* Hydraulic Action: The force of water hitting the cliffs, often force air pockets (mini explosions) in to cracks of the rocks, forcing apart parts of the river banks.
Erosion
River erosion is the wearing away of the land as the water flows past banks. The four main types of erosion are:
* Abrasion: scraping away of the river bed and banks, this occurs when the materials that are carried by the river.
* Solution: chemicals in the river that dissolve minerals from the bank, carrying them away in solution.
* Hydraulic Action: The force of water hitting the cliffs, often force air pockets (mini explosions) in to cracks of the rocks, forcing apart parts of the river banks.
MIDDLE COURSE:
Transportation
the type of transport taking place depends on the size of the sediment and the amount of energy available to transport. The four main ways that material can be transported is by solution, suspension, saltation and traction.
* Traction: Heaviest material is rolled along the river bed.
* Saltation: The movement of sand-size particles over an uneven surface in a turbulent flow of water, going in a 'lead-frog' motion.
* Suspension: small particles are carried within the water by a turbulent flow.
* Solution: Some minerals dissolve in water to be carried down the river in a solution.
Transportation
the type of transport taking place depends on the size of the sediment and the amount of energy available to transport. The four main ways that material can be transported is by solution, suspension, saltation and traction.
* Traction: Heaviest material is rolled along the river bed.
* Saltation: The movement of sand-size particles over an uneven surface in a turbulent flow of water, going in a 'lead-frog' motion.
* Suspension: small particles are carried within the water by a turbulent flow.
* Solution: Some minerals dissolve in water to be carried down the river in a solution.
LOWER COURSE:
Deposition
Deposition occurs when material carried by the river is dropped because there is no longer sufficient energy to transport material.
This can be when a river enters a shallow area or towards its mouth. Deposition of material results in the formation of features such as slip-off slopes, levees (raised banks) and the a floodplain.
The largest material is dropped first because it requires the most energy to be transported. Rivers carry different sediments including rocks, boulders, silt, mud, pebbles and stones so deposition removes it's sediments.
http://www.cleo.net.uk/resources/displayframe.php?src=309/consultants_resources%2F_files%2Fmeander4.swf
Deposition
Deposition occurs when material carried by the river is dropped because there is no longer sufficient energy to transport material.
This can be when a river enters a shallow area or towards its mouth. Deposition of material results in the formation of features such as slip-off slopes, levees (raised banks) and the a floodplain.
The largest material is dropped first because it requires the most energy to be transported. Rivers carry different sediments including rocks, boulders, silt, mud, pebbles and stones so deposition removes it's sediments.
http://www.cleo.net.uk/resources/displayframe.php?src=309/consultants_resources%2F_files%2Fmeander4.swf