Rivers Flashcards
What is a valley in a river basin
An area with higher ground on either side.
Where a river runs through.
What is a floodplain in a river basin
The land either side of the river which may flood
if the river overflows.
What is the mouth in a river basin
Where the river ends and meets the sea
What is the confluence in a river basin
The meeting point of two rivers.
What is the tributary in a river basin
Smaller rivers meeting a main one
What is a watershed in a river basin
Imaginary outline of a river basin. An area of
higher ground.
What is a river basin
The area inside the watershed where all rain will
collect into a river.
What is the source in the river basin
Where the river starts
What is hydraulic action
The force of the river against the
banks can cause air to be trapped in cracks. The
pressure weakens the banks and gradually wears it away.
What is abrasion
Rocks carried along by the river rub and scrape
along the river bed and banks.
What is attrition
Rocks being carried by the river smash together
and break into smaller, smoother and rounder particles.
How does the river erosion ‘solution’ work
Smaller soluable rocks are dissolved into the river.
How does a river move material downstream?
Through transportation. This happens when dissolved material which you cant see is carried along as a solution. Then small light particles of rock and soil are carried along as a suspension. They make the water look cloudy or muddy. Lastly, the heavier material is carried along the bottom. It is called the bedload. The larger stones and rock roll along and Sand and small stones bounce along.
How does the river process Suspension work?
Fine light material is carried along in the water.
How does the river processes Salation work
Small pebbles and stones are bounced along the river bed.
How is the river transportation processes Traction work
Large boulders and rocks are rolled along the river bed.
What is river Deposition
Deposition This is where the river drops its material. It occurs when the velocity of the river decreases, energy is reduced and the river can no longer hold all its material.
What is the deposited material called when a river deposits material
Sediment
How does a river change from the upper to lower course? (Long profile)
The long profile of a river shows how the gradient changes as the river flows from source to mouth. The gradient is steep in the upper course, more gentle in the middle, and almost flat in the lower course.
In what course is there the most energy and erosion
The upper course
In which course is there both erosion and deposition occuring
The middle course
In which course does deposition win out as the river loses energy
The lower course
What is a delta
Deltas are wetlands that form as rivers empty their water and sediment into another body of water, such as an ocean, lake, or another river. Although very uncommon, deltas can also empty into land.
