Landform process & change

Question 1

What processes cause river landforms to change overtime?

Answer 1

• fluvial erosion
• transportation
• deposition

Question 2

Define fluvial

Answer 2

Referring to a river & its landforms

Question 3

Define erosion

Answer 3

The process of wearing away the land

Question 4

Define transportation

Answer 4

The movement of material by the flow of the water

Question 5

Define deposition

Answer 5

The process of material carried by the river being dropped

Question 6

Define bedload

Answer 6

Material carried by the river being bounced or rolled along the bed

Question 7

Define meander

Answer 7

A bend in the river, formed by lateral erosion

Question 8

What are the types of erosional processes that occur on the river channel?

Answer 8

• abrasion
• hydraulic action
• solution

Question 9

What are the types of erosional processes that occur on the river bed?

Answer 9

• attrition
• abrasion

Question 10

Define abrasion

Answer 10

Material carried by the river hitting the river bed & banks & wearing them away

Question 11

Define hydraulic action

Answer 11

The force of the water pushing air into gaps in the soil & rocks, causing them to be wider

Question 12

Define solution

Answer 12

When the water has a chemical reaction with rocks made from calcium carbonate (limestone/chalk) and dissolves them

Question 13

Define attrition

Answer 13

Rocks carried by the river collide together & are broken down becoming into smaller & rounder rocks

Question 14

What does river transportation depend on?

Answer 14

• speed of the flow
• weight of the load

Question 15

What are the different ways that transportation occurs in the river?

Answer 15

• solution
• suspension
• saltation
• traction

Question 16

Define suspension

Answer 16

Fine light material is carried in the river flow, as suspended load

Question 17

Define saltation

Answer 17

Small pebbles/stones bounced along the bed & banks of the river

Question 18

Define traction

Answer 18

Large boulders rolled along the bed & banks

Question 19

Where does deposition occur in a river?

Answer 19

• river channel
• inside a meander
• mouth of the river

Question 20

Why does deposition occur in the river channel?

Answer 20

There is reduced movement of water caused by lack of rainfall

Question 21

Why does deposition occur in the meander?

Answer 21

The majority of the water is on the outer bend, therefore the water on the inner bend is slow & can’t transport load

Question 22

Why does deposition occur in the mouth of the river?

Answer 22

The water opposes the direction of the sea

Question 23

What river landforms are shaped by fluvial processes?

Answer 23

• v-shaped valleys
• waterfalls
• gorges
• floodplains
• meanders

Question 24

Define v-shaped valley

Answer 24

A narrow valley with steep sloping sides found in the river’s upper course

Question 25

Define waterfall

Answer 25

Water falling from a higher level to a lower level caused by glacial & differential erosion

Question 26

What 2 ways can waterfalls be formed?

Answer 26

- glacial erosion - differential erosion

Question 27

Define glacial erosion

Answer 27

Erosion of the landscape caused by glaciers during the ice age

Question 28

Describe the process of waterfall formation through glacial erosion

Answer 28

- during ice age, glaciers carved steep valleys into the landscape - valleys left hanging above one another - glaciers melted→water drains from small valleys into large ones

Question 29

Define differential erosion

Answer 29

Waterfalls are formed due to a change in rock structure

Question 30

Describe the process of waterfall formation through differential erosion?

Answer 30

- waterfalls occur where a band of HR overlies SR - as water falls, hydraulic action continues to erode the SR underneath the HR - as SR is eroded, overhang becomes heavy & collapses due to gravity, causing waterfall to retreat - plunge pool forms underneath waterfall due to force of water hitting the river bed

Question 31

Define gorge

Answer 31

A steep-sided narrow valley formed by a retreating waterfall

Question 32

Define floodplain

Answer 32

A flat piece of land on either side of a river forming the valley floor

Question 33

Define vertical erosion

Answer 33

Sideways erosion of the river channel that deepens it

Question 34

Define interlocking spurs

Answer 34

Hard resistant rocks that a river cannot easily erode & therefore has to move around it

Question 35

Define plunge pool

Answer 35

A deepened part of the river bed at the base of the waterfall caused by the impact of the falling water