Long Profile And Landforms in Rivers

Question 1

What is a meander?

Answer 1

When the river erodes laterally, forming large bends, and then horse shoe like loops

Formation- due to both deposition and erosion

Question 2

What is an oxbow lake?

Answer 2

During a flood when the river has a higher discharge and more energy, the ends join, the loop is cut off from the main channel.

Cut off loop= oxbow lake

Question 3

What are the 3 courses?

Answer 3

Upper
Middle
Lower

Question 4

What are features of the lower course?

Answer 4

• river has a high volume and large discharge
• river channel becomes deep and wide and landscape around is flat
• when river reaches the end of its journey, energy levels are low and decomposition takes place

Question 5

What are features of the middle course?

Answer 5

• river has more energy and a high volume of water
• gradient=gentle and lateral (sideways) because erosion has widened the channel
• river channel=deepened
• larger channel=less friction=river flows faster

Question 6

What are features of a upper course?

Answer 6

-V-shaped valleys/interlocking Spurs
-as the river moves through the upper course it cuts downwards
-gradient=steep
River channel=narrow

Question 7

Describe each courses river bed

Answer 7

Upper - vertical erosion
Middle - lateral erosion
Lower - alluvium deposition

Question 8

What course has the widest flood plain?

Answer 8

Lower course

Question 9

What is a floodplain?

Answer 9

The area around a river that is covered in times of floods

Question 10

Describe how a floodplain works

Answer 10

• Very fertile area due to the rich alluvium deposited by floodwater- making floodplain me a good place for agriculture
• build up of alluvium on the river bank can create levees, which raise the river bank

Question 11

Where are deltas formed? How are they formed?

Answer 11

Found at the mouth of large rivers

Formed when rivers deposit it’s material faster than the sea can remove it

Question 12

What are the 3 main types of delta?

Answer 12

• arcuate or fan shaped
• cuspate
• birds foot

Question 13

What is arcuate or fan shaped delta?

Include an example.

Answer 13

The land around the river mouth arches out into the sea and the river splits many times on the way to the sea-creating a fan effect
Eg. The Niger delta

Question 14

What is a cuspate delta?

Answer 14

The land around the mouth of the river juts out arrow- like into the sea

Question 15

What is a birds foot delta?

Answer 15

The river splits on the way to the sea, each party of the river juts out into the sea, rather like a birds foot