Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

Physical geography > Coasts 2 - Coastal processes > Flashcards

Coasts 2 - Coastal processes Flashcards

1
Q

What are the 6 types of erosion

A
  • Corrasion (Abrasion)
  • Hydraulic action
  • Cavitation
  • Wave quarrying
  • Solution (Corrosion)
  • Attrition
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

What is corrosion (Abrasion)

A

Bits of sediment transported by the waves, small and grind against rocks and cliffs, breaking bits off and smoothing surfaces

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

What is hydraulic action

A

Air in cracks in cliffs are compressed when waves crash. The pressure exerted by the compressed air breaks off rock pieces

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

What is cavitation?

A

As waves recede the compressed air expands exerting pressure on the rock and causing bits to break off

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

What is wave quarrying

A

The energy of a wave as it breaks against a cliff enough to attack bits of rock222222

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

What is solution (Corrosion)?

A

Soluble rocks gradually dissolve In seawater

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

What is attrition?

A

Bits of rock in the water smash against each other and break into smaller pieces

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

What Is transportation

A

The process of eroded material being moved

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

What are 4 transportation processes?

A
  • Solution
  • Suspension
  • Saltation
  • Traction
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

What is solution?

A

Substances that dissolve are carried along the water eg.- limestone is dissolved into slightly acidic water

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

What is suspension>

A

Very fine material, like slit and clay particles is whipped up by turbulence and carried along the water causing them to BOUNCE along the seas bed

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

What is saltation?

A

Larger particles like gravel and pebbles are too heavy to be carried along in water. Most eroded material is transported like this

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

What is traction?

A

Very large particles like boulders are pushed along the seabed by the force of water

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

How does longshore drift work?

A

Swash carries sediment up the beach, parallel to the prevailing wind. Backwash carries sediment back down the beach at right angles to the shoreline.
When there’s an angle between the prevailing wind and shoreline, a few rounds of swash and backwash move the sediment along shoreline

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

What is deposition

A

The material Being transported and dropped at the coast

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

What are the 2 types of deposition

A
  • Marine
  • Aeolian
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

What’s marine deposition?

A

Sediment carried by seawater that’s deposited

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

What is aeolian deposition?

A

Sediment carried by wind is deposited

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

When does deposition occur?

A

When sediment load exceeds the ability of wind or water to carry it

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

Why does this happen?

A

Because sediment load increases or wind or water flow slows down

21
Q

Why do wind and water slow down?

A

Friction increases and flow becomes turbulent

22
Q

How does friction increase?

A

Waves enter shallow water or wind reaches land, friction between water / wind and the ground increases, slowingg down the water or wind

23
Q

How do flows become turbulent

A

If water or wind encounters an obstacle the flows become rougher and overall speed decreases

24
Q

What happens if the wind drops?

A

Wave height, speed and energy absorption decrease

25
Q

What is sub-aerial weathering?

A

The gradual breakdown of rocks by agents like ice, salt, roots and acids

26
Q

What does weathering do?

A

Weakens cliffs and makes them more vulnerable to erosion

27
Q

What 4 types of weathering affect the coast

A
  • Salt Weathering
  • Freeze - thaw weathering
  • Wetting and drying
  • Chemical weathering
28
Q

What is salt weathering caused by?

A

Saline (salty) water

29
Q

How does saline water enter the rocks?

A

Through pores or cracks at high tide

30
Q

What happens as the tide goes out?

A

Rocks dry and water evaporates forming salt crystals/ As they form, they expand, exerting pressure on rocks causing pieces to fall off

31
Q

When does freeze-thaw weathering occur?

A

In areas where temperature fluctuates above and below freezing

32
Q

How does water enter the rocks?

A

In the joints and crevices

33
Q

What happens as the temperature freezes?

A

Water in cracks freeze and expand. Over time, repeated freeze-thaw weakens the rocks meaning pieces fall off

34
Q

What happens when rock containing clay gets wet?

A

Expand and the pressure caused by this breaks off fragments of the rock

35
Q

What is chemical weathering?

A

The breakdown of rock by changing its chemical composition

36
Q

Give an example of chemical weathering

A

CO2 in the atmosphere dissolves in rainwater, forming weak carbonic acid. The acid reacts with rock that contains calcium carbonate

37
Q

what is mass movement

A

The shifting of material downhill due to gravity

38
Q

When is mass movement more likely in coast areas

A

When cliffs are undercut by wave action - causing an unsupported overhang which is likely to collapse

39
Q

What are the 4 types of mass movement

A
  • Landslides
  • Slumping
  • Rockfalls
  • Mudflows
40
Q

How can material move gradually downwards?

A

By soil creep

41
Q

What are slides?

A

Material shifts in a straight line

42
Q

What are slumps?

A

material shifts with a rotation

43
Q

What are rockfalls?

A

Material breaks up and falls

44
Q

What are mudflows

A

Material flows downslope

45
Q

What’s an example of an unconsolidated rock?

A

clay

46
Q

What’s likely to happen to unconsolidated rock?

A

They’re prone to collapse as there’s little friction between particles to hold them together

47
Q

What happens when there’s heavy rain on unconsolidated rock?

A

It can saturate the rock and reduces the friction making it more likely to collapse

48
Q

What is runoff

A

The flow of water over the land

49
Q

What can runoff do?

A

Erodes fine particles and transport them downslope

Physical geography (9 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions