MIDDLE AND LOWER COURSE

Question 1

What erosion most dominant

Answer 1

Lateral erosion

Question 2

What is river meandering, detail

Answer 2

The turning of rivers.

Velocity on outside bend is faster than the velocity of the inside bend.

Rivercliff forms in outside bend due to undercutting and deposition happens in inside bend due to less energy, forms slip-off slope

Question 3

Oxbow lakes

Answer 3

Are dried up areas which the river used to flow through.

When 2 outside bends get very close together and eventually meet. So it is easier for water to flow straight instead of turning.

Question 4

Floodplains

Answer 4

• Flat land in valley bottom
• River bed+bank is made of fine material, river floods and fine material deposited along flood plain
• Gives new layer of soil
• Thin and fertile soil = agriculture
• Risk of flooding = no buildings

Question 5

Levees

Answer 5

• Natural embankment - result of flooding
• Small particles deposited far away and larger ones deposited closer to the river,
• large particles clump and form levee
• Vegetation increase friction, so heavier material is deposited even earlier

Question 6

Estuary

Answer 6

• Where river enters the sea
• Brackish water
• Wide and opens up as it gets closer to sea
• Widened by sea storms and other processes at the coast

Question 7

Deltas

Answer 7

• Vast areas of alluvium
• When river meets denser sea, it loses its energy, so deposits a lot of material
• Material is deposited at a faster rate than it is being removed
• River flow blocked by deposited material, forms distributaries- branch of river leaving main river (large river splitting into smaller rivers)