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GCSE Geography > River Landscapes > Flashcards

Flashcards in River Landscapes Deck (45):
1

What are the two physical processes that shape a river landscape

Weathering and Mass Movement

2

What are the three types of Weathering

Mechanical, Chemical and Biological

3

What is Mechanical weathering?

Freeze Thaw Action

4

What is chemical weathering?

Acid rain

5

What is biological weathering?

Roots grow into cracks and split rocks apart

6

What is mass movement?

Overtime the sides of a river valley become less steep as material is moved from the top to the bottom

7

Give two examples of Mass Movement

Sliding and Slumping

8

What is sliding?

Where rock, weathered or eroded material or earth moves down a slope. Gravity pulls the weakened material quickly downwards

9

What is slumping?

When the river erodes the bottom of the valley slope, making it steeper. Material above slides downwards, particularly if it is saturated with rainwater

10

What are the four types of erosion?

- Hydraulic Action
- Attrition
- Solution
-Abrasion

11

What is hydraulic action?

The force of the water on the bed and banks of the river removes material

12

What is attrition?

The load that is carried by the river bumps together and wear down into smaller, smoother pieces

13

What is solution?

Some rock materials dissolving in river water

14

What is abrasion?

Material carried by the river rubs against the bed and banks and wears the away

15

What is transport?

The way in which the river carries eroded material or load

16

What are the four main types of transportation?

- Traction
- Suspension
- Saltation
-Solution

17

What is traction?

Large boulders are rolled along the river bed

18

What is saltation?

Smaller pebbles are bounced along the river bed, picked up then dropped as the river flow changes

19

What is suspension?

Finer sand and slit particles are carried along in the flow, giving the river a brown appearance

20

What is Solution?

Some minerals are dissolved in the water and carried along in the flow

21

What is the gradient of a upper course, middle course and lower course?

Upper course - steep
Middle course - less steep
Lower course - shallow gradient

22

What is the discharge of the upper course, middle course and lower course?

Upper course - small
Middle course - large
Lower course - very large

23

What is the depth of the upper, middle and lower course?

- shallow
- deeper
- deep

24

What is the channel shape of upper, middle and lower course?

- narrow steep sides
- flat steep sides
- flat floor gently sloping sides

25

What is velocity in upper, middle and lower course?

- quite fast
- fast
- very fast

26

What is the valley profile of a upper, middle and lower course?

- steep sides
- flat with steep sides
- flat with gently sloping slides

27

What is features of a upper, middle and lower course?

- waterfalls, interlocking Spurs
- meanders, flood plains
- meanders, floodplain, levee and oxbow lakes

28

What are the impacts of climate on river on landforms and landscapes?

- Erosion rate
- Transport rate
- Weathering
- Amount of discharge

29

What can increase the risk of flooding?

- Increasing frequency of storms
- Increasing periods of hot, dry weather
- Soil becoming impermeable during cold conditions

30

What is a interlocking Spurs?

- The river at its source is small and has limited energy
- It flows naturally from side to side, around ridges in the valley sides called Spurs
- the spurs becoming interlocking with those on the other side of the valley

31

How is a waterfall formed?

- Increase in vertical erosion
- They form where there is a layer of hard, resistant rock overlying a softer, less resistant rock

32

What is a gorge?

Over a long time, the process of undercutting and collapse is repeated, and the waterfall retreats, forming a steep sided gorge

33

How is a floodplain formed?

The wide, flat area of land either side of a river and experiences floods when the river tops its banks

34

How does a levee develop?

The deposition process, which takes place during flooding, continues until eventually embankments, much of larger, heavier sediment, are created beside the river

35

How is a meander formed?

- The river erodes laterally and starts to form large bends
- the bends get bigger and wider, and eventually develop into a horseshoe shape

36

How does urbanisation affect the river landscape?

- causing towns to grow
- Increasing in demand for housing has led to new houses being built
- Rivers may be channelised or made to flow underground to make room for urban developments

37

Give four examples of physical causes

- Rainfall intensity
- Geology
- Snowmelt
- Drainage basin

38

What is the physical effect of flooding?

Includes landslides, soil erosion, loss of natural habitats, contamination of water supplies

39

What is the human effects of flooding?

Includes depth, disease, damage to property, insurance claims, loss of livelihoods and loss of crops

40

What is hard engineering?

Dams and reservoirs and channelisation

41

What is dams and reservoirs?

Barriers constructed to hold back water in artificial lakes

42

What is channelisation?

Deepening or widening the river channel

43

Give two examples of soft engineering?

- Floodplain zoning
- Washlands

44

What is floodplain zoning?

Prevents development in areas most prone to flooding next to rivers

45

What is washlands?

Areas next to rivers that are deliberately flooded to avoid flooding residential or important agricultural areas