Rivers Flashcards
What is a drainage basin ?
The area of land drained by a river
What is lateral erosion ?
It is erosion that happens sideways
What is attrition ?
When rocks carried by the river smash into each other becoming smaller and rounder
What is abrasion ?
When rocks smash against the river banks wearing them away
What is hydraulic action ?
When water crashes into gaps in the rocks causing them to break
What is solution ?
Minerals dissolved in the water are carried by the river
What is suspension ?
Particles that are carried along in the water
What is traction ?
The bedload that rolls along the riverbed
What is saltation ?
The sediment bounces along the bed of the river
What are the different types of erosion in a river ?
Attrition, abrasion, hydraulic action, solution
What are the different types of transportation in a river ?
Traction, saltation, suspension and solution
What are the main landforms in a river ?
Waterfalls, meanders, gorges and oxbow lakes.
How are waterfalls formed ?
> Hard rock is undercut by erosion of the soft rock
A plunge pool is formed
The overhang collapses due to lack of support
Gradually the waterfall retreats
Describe a cross section of a meander
> Sand and shingle is deposited on the inside of the bend where there is a slower current
The bank on the outside of the bend is being undercut by lateral erosion, as this is where the fastest current is
What is deposition ?
It is when the river drops off the material it is carrying e.g. rocks
