Rivers Flashcards
What are the different types of erosion rivers experience
Attrition
Abrasion
Solution
Hydraulic action
What are attrition and hydraulic action in rivers
Attrition= the action of rocks banging into eachother and making the stones smaller and rounded
Hydraulic action = the force of the water hitting riverbed and banks
What are solution and Abrasion in rivers
Solution - the ph of the water slowly wearing down rocks over time
Abrasion = when the rocks bounce across the river bed causing particles to become eroded
What are the types of river transportation
Suspension
Solution
Salitation
Traction
What are traction and salitation in rivers
Traction - where large rocks and boulders are rolled along the river bed
Saltation - where small stones are bounced along the river bed
What are some upper course features and processes
Narrow v shaped valleys
Gorges are found here from waterfalls
Rapids and large boulders (found from the weathering of steep valleys)
Vertical erosion
What sre some middle course features and processes
River begins to meander
Wider valleys
Ox bow lakes
Levees are formed which are river banks formed by flooding
Wide floodplains
What sre some Lower course features and processes
River at its slowest -lost all energy
Very wide flat valleys
Large meanders
Whats a tributary and a confluence
Tributary - Small streams which feed into the main river
Confluence - where two or more tributaries meet
What is a watershed and a channel
Watershed - an area of high land which surrounds the river drainage basin
Channel- the main body of the river
What are the processes which cause a v shaped valley
The river erodeds downwards via Abrasion
As the river cuts down the steep sides are attacked by weathering.
Therefore loosening soil and rock
The loosened material gradually falls into the river via gravity
When all loosened material has fallen in the river the result is a v shaped valley
Where does erosion and deposition occur on river bends
Erosion = happens on the outside bend in the “thalweg “which means
the fastest flow
Depostion= on the inside bend as the channel moves slower and the material is suspension is dropped
What are the physical causes of flooding
Heavy rain
Prolonged rain
Snow melt
Impermeable rock types
Low lying land
What are the Human causes of flooding
Deforestation- less interception more surfsce run off
Urbanisation - Impermeable ground means water can’t be absorbed meaning more surfsce run off
WHere is the river tees
The river tees is in the north east of England High in the pennine hills near cross fell