River Landforms

Question 0

Name the landform that is left as a waterfall retreats.

Answer 0

A gorge

Question 1

Describe how waterfalls are formed.

Answer 1

Waterfalls form where a river flows over an area of hard rock followed by an area of softer rock.
The softer rock is eroded more than the hard rock, creating a step in the river.
As water goes over the step it erodes more and more of the softer rock.
A steep drop is eventually created, which is called a waterfall.

Question 2

What is a flood plain?

Answer 2

The wide valley floor on either side of a river which occasionally gets flooded.

Question 3

Explain how flood plains are built up.

Answer 3

When a river floods onto a flood plain the water slows down
and deposits the eroded material it’s transporting, which builds up the flood plain.
Flood plains are also built up by the deposition that happens on the slip-off slopes of meanders.

Question 4

What are levees?

Answer 4

Natural embankments along the edges of a river channel.

Question 5

Explain how levees are formed.

Answer 5

When a river floods the heaviest material is deposited closest to the river channel because it gets dropped first when the river slows down.
Over time, the deposited material builds up, creating levees along the edges of the river channel.