Brainscape's Knowledge GenomeTM

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


See full index

A Level Geography AQA > Coastal Systems and Landscapes > Flashcards

Coastal Systems and Landscapes Flashcards

You may prefer our related Brainscape-certified flashcards:
U.S. Geography flashcards World Geography flashcards
1
Q

What is a sediment cell?

A

A largely self-contained stretch of coastline. They are regarded as closed systems as sediment is not usually transferred from one to the other.

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

What are the sources of energy at coastlines?

A

Sun and wind

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

Where do the prevailing winds come from in the UK?

A

The south-west as a result of air moving from the subtropical high pressure belt.

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

What factors affect wave energy?

A
  • The strength of the wind
  • The duration of the wind
  • The fetch (distance of open water which the wind blows)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

How are waves created?

A

As air moves across the water, frictional drag disturbs the surface and forms waves. The waves are larger near the shore as waves are driven onshore to break on the beach.

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

What are the two types of wave?

A

Constructive and destructive

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

What are the characteristics of constructive waves?

A
  • Waves are generated by distant weather systems in the open ocean
  • low, long-wavelength surging waves
  • Strong swash, weak backwash
  • Builds up sediment on the beach
  • more commonly found along gentle beach profiles
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

What are the characteristics of destructive waves?

A
  • Generated by local storms
  • High, short-wavelength plunging waves
  • Weak swash, strong backwash
  • Removes sediment from the beach
  • Associated with steeper coastlines
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

What are tides?

A

Changes in the water level of seas and oceans caused by the gravitational pull of the moon (and the sun to some extent).

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

What is the tidal range?

A

The relative difference in height between high and low tides.

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

What are the highest and lowest tides called?

A

Lowest- Neap tides

Highest- Spring tides

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

What are high and low energy coastlines associated with?

A

High- erosion

Low- deposition

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

What does wave refraction at headlands cause?

A

It causes energy to be concentrated at headlands and dissipated at bays. This is what causes bays to be created between headlands, due to the softer geology between headlands being eroded away reducing the wave energy via refraction around the headland.

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

What sources of sediment are there?

A
  • Rivers (transported sediment)
  • Cliffs (erosion)
  • Long shore drift (movement of sand across beaches)
  • Wind (suspended sediment)
  • Glaciers (ice shelves can deposit sediment)
  • Offshore (transferred by waves)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

What inputs, stores and transfers of sediment are there in sediment cells?

A

Inputs- Rivers, cliff erosion, off shore…
transfers- Long-shore drift and ocean currents
stores- beaches, dunes, bars…

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

How many major sediment cells are there in the UK?

A

11

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

What is a sediment budget?

A

A system of inputs and outputs of sediment that seeks to achieve a state of dynamic equilibrium.

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

What is weathering and what are the three types?

A

Weathering is the break down or disintegration of rock in situ or close to the ground surface. The three types are mechanical (physical), biological and chemical weathering.

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

What is freeze-thaw?

A

When water enters a crack or joint in the rock and freezes and expands, exerting pressure on the rock. The constant freezing and thawing causes the rock to weather. (Mechanical weathering)

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

What is salt-crystallisation?

A

When salt water evaporates, leaving salt crystals behind. These can grow over time and exert stresses in the rock, causing it to weather. (Mechanical weathering)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

What can occur in biological weathering?

A
  • Plant roots can grow into cracks and widen, causing the rocks to break.
  • Birds and animals as well as marine organisms can burrow into cliffs causing them to weather.
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

What can occur in chemical weathering?

A
  • Rainwater can absorb CO2 from the air to form weak carbonic acid which can dissolve rocks like limestone and chalk
  • Rock materials can react with oxygen
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

What is mass movement?

A

The downwards movement of material under the influence of gravity.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q

What is soil creep?

A

The extremely slow movement of soil particles down hill .

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
Q

What are mudflows?

A

Earth and mud flowing downhill usually over weak bedrock such as clay.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
26
Q

What is a landslide?

A

A black of rock moving very rapidly downhill along a planar surface.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
27
Q

What is a rockfall?

A

A sudden collapse or breaking away of individual rock fragments at a cliff face.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
28
Q

What is a slump/landslip?

A

Material sliding rapidly downhill down a curved surface often occurring in weak clays and sand.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
29
Q

What is solifluction?

A

The gradual movement of wet soil or other material down a slope, especially where frozen subsoil acts as a barrier to the percolation of water.

30
Q

What is hydraulic action?

A

The erosion that occurs when the motion of water against a rock surface produces mechanical weathering. Most generally, it is the ability of moving water (flowing or waves) to dislodge and transport rock particles.

31
Q

What is corrasion?

A

When sediment is hurled at a cliff face, causing it to erode.

32
Q

What is abrasion?

A

When sediment is dragged up and down or across the shoreline eroding and smoothing rocky surfaces.

33
Q

What is solution?

A

What is formed when weak acids in sea water dissolve rock.

34
Q

What is attrition?

A

The gradual wearing down of rock particles by impact and abrasion as pieces of rock are moved by tides and currents, causing them to become rounder and smoother.

35
Q

What factors affect coastal erosion?

A
  • Waves (type, height, strength…)
  • Geology (soft/hard)
  • Presence of a beach (absorbs wave impacts)
  • Sub-aerial processes
  • Coastal management
36
Q

What is traction?

A

The rolling of coarse sediment along the seabed that is too heavy to be piked up by the sea.

37
Q

What is saltation?

A

sediment being “bounced” across the seabed.

38
Q

What is suspension

A

Smaller, lighter sediment picked up and carried by the flow of water.

39
Q

What are the four types of coastal transportation processes?

A

Traction, saltation, suspension and solution.

40
Q

What is long-shore drift?

A

The movement of material along a coast by waves which approach at an angle to the shore but recede directly away from it.

41
Q

What is a wave-cut platform?

A

The narrow flat area often found at the base of a sea cliff or along the shoreline of a lake, bay, or sea that was created by erosion when the under-cut cliff collpases.

42
Q

What is the sequence in the erosion of a cliff profile?

A

crack -> cave -> arch -> stack -> stump

43
Q

How does a stump form?

A

Waves erode joints and cracks to form caves, these then erode further to form arches. The arch collapses to leave a stack which is then eroded to leave a stump.

44
Q

What is the difference between a swash-aligned and a drift-aligned beach?

A

Swash-aligned beaches form in low-energy environments that are affected by waves arrive roughly parallel to the shore. Whereas drift-aligned beaches form where the waves approach the coast at an angle.

45
Q

What is a spit and how does it form?

A

A long narrow feature made of sand or shingle that extends from the land into the sea. They form on drift aligned beaches when LSD moves shingle and sand but the coastline changes direction (e.g. due to a river estuary) so sediment builds up forming a spit.

46
Q

What is a tombolo and how does it form?

A

A ridge of sand and shingle that has formed between a small island and the mainland. They form similarly to spits.

47
Q

What are barrier beach and how do they form?

A

it is where a spit extends across a bay to join two headlands due to LSD.

48
Q

What are offshore bars?

A

They are submerged ridges of sand or coarse sediment created by waves off shore from the coast.

49
Q

What are offshore bars and how do they form?

A

They are submerged ridges of sand or coarse sediment created by waves off shore from the coast.

50
Q

What is required for sand dunes to be able to form?

A
  • Large quantities of available sand washed onshore by constructive waves
  • A large tidal range, creating exposure of sand that will dry out at low tide
  • Dominant offshore winds that will blow dried sand to the back of the beach
51
Q

How do sand dunes form?

A

The first colonising plants (pioneer species) can survive in dry, salty and exposed conditions so when they form they can trap sand and form fore dunes. As the environment changes over time, different species colonise the sand dunes until they become stable.

52
Q

What is the sequence that sand dunes go through?

A

Embryo dune -> Fore dune (yellow) -> fixed dunes (grey) -> Wasting dunes (slacks and blowouts)

53
Q

What are salt marshes?

A

Areas of flat, silty sediment that accumulate around estuaries or lagoons,

54
Q

Where do salt marshes form?

A
  • In sheltered areas where deposition occurs
  • Where salt and freshwater meet
  • Where there are no strong tides or currents
55
Q

How do salt marshes form?

A

Mud is deposited close to the high tide line, which sinks to the sea bed. Pioneer species like cordgrass start to colonise and trap further deposits. Gradually the mud level rises above the tide and a wider range of plants grow. Eventually shrubs and trees will grow when the succession reaches its climax.

56
Q

What is eusostatic change?

A

When the sea level itself rises or falls

57
Q

What is isostatic change?

A

When the land rises or falls relative to the sea.

58
Q

What are the three types of submergent land forms?

A

Rias, fjords and dalmatian coasts

59
Q

What is a ria?

A

A coastal inlet formed by the partial submergence of an unglaciated river valley.

60
Q

What is a fjord?

A

A long, narrow, deep inlet of the sea between high cliffs, formed by submergence of a glaciated valley

61
Q

What are the main types of hard engineering coastal management?

A

Groynes, sea walls, rip rap, revetments and offshore breakwaters.

62
Q

What are the main types of soft engineering coastal management?

A

Beach nourishment, dune stabilisation, marsh creation and cliff regrading and drainage.

63
Q

What are groynes and what are the pros and cons of them?

A

Timber or rock structures built perpendicular to the coastline to trap sediment moving along the coastline due to LSD

pros: work with natural processes, quite cheap
cons: starve beaches further along the coast and can be unattractive

64
Q

What are sea walls and what are the pros and cons of them?

A

Stone or concrete walls at the foot of a cliff or at the top of a beach.

pros: effective at preventing erosion
cons: reflect wave energy rather than absorbing it, unnatural looking, expensive to build and maintain

65
Q

What is rip rap and what are the pros and cons of it?

A

Large rocks placed at the foot of a cliff or the top of a beach.

pros: quite cheap and easy to maintain, can be used for recreation
cons: can look out of place, dangerous for people who climb on them

66
Q

What are revetments and what are the pros and cons of them?

A

Sloping wooden or concrete structures placed at the foot of cliff to break up wave energy.

pros: quite cheap
cons: can need lots of maintenance, can be unattractive

67
Q

What is an offshore breakwater and what are the pros and cons of it?

A

A partly submerged rock barrier to break up waves.

pros: they are effective
cons: unattractive, potential navigation hazard

68
Q

What is beach nourishment and what are the pros and cons of it?

A

The addition of sand or pebbles to an existing beach.

pros: quite cheap and easy to maintain, blends in with the existing beach and good for tourism
cons: needs constant maintenance

69
Q

What is dune stabilisation and what are the pros and cons of it?

A

Planting marram grass to encourage growth and fencing off dunes from the public

pros: maintains coastal environment, relatively cheap and sustainable
cons: time consuming to plant grass

70
Q

What is marsh creation and what are the pros and cons of it?

A

A form of managed retreat by allowing low-lying coastal areas to be flooded by the sea causing salt marshes to be created.

pros: quite cheap, creates a natural buffer, encourages biodiversity
cons: agricultural land is lost meaning land-owners need to be compensated

71
Q

What are the four main shoreline management plan strategies?

A
  • Advance the line
  • Hold the line
  • Managed retreat
  • Do nothing

A Level Geography AQA (10 decks)

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