Brainscape's Knowledge GenomeTM

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


See full index

Geography > Coasts (Definitions) > Flashcards

Coasts (Definitions) Flashcards

1
Q

What is a coast?

A

The interface between land and sea, can be viewed as a system, with inputs, processes and outputs.

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

What are the 4 inputs for a coastal system?

A

Wave energy
Geological structure
Sub-aerial activity
Human activity

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

What is the fetch of a wave?

A

The distance over which the wind blows in a constant direction across the surface of the water

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

What are the 4 processes at a coastal system?

A

Wave erosion
Mass movement
Hard/soft engineering
Transport

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

What are the 2 outputs at a coastal system?

A
  • Landforms of erosion
  • Landforms of deposition
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

The 7 processes of coastal erosion:

A

Abrasion - Waves throw loose material at cliffs
Attrition - Movement sandpapers rocks into smoother and rounded rocks
Solution - Carbonic acid in sea water reacts, and spray corrodes rocks, so they disintegrate
Biological activity - Secretions from algae attack rocks, or some molluscs can bore holes in them
Wave pounding - Wave impact can loosen cliff face rock.
Hydraulic pressure -Waves enter tiny crevice/crack and air is trapped
Sub aerial weathering - Rain leading to saturation of cliff material and the failure of cliff by mass movement

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

What determines the amount of energy waves have?

A

Higher wind speeds impart more energy to the waters surface, creating larger and more powerful waves
A longer fetch allows the wind to transfer more energy to the water, resulting in larger waves

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

What is meant by wave pounding?

A

The forceful impact of large and powerful waves on a cliff face or coastal structure, pounding or battering effect is pronounced during storms or periods of high winds, with intensified waves.

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

What are two examples of mass movement?

A

Landslides involve the rapid downslope movement of rock, soil, and debris along a defined surface, triggered by many diff factors or activities that disturb the stability of a slope
Mudflows are fast-moving mixtures of water, mud, rocks, and debris that flow downslope. They are similar to landslides but involve a higher proportion of water, giving them a fluid-like consistency.
Sub aerial activity triggers this movement when soils are more saturated.

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

What do all rocks have and why is this important?

A

Minerals, are fundamental to the composition, classification, and understanding of rocks

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

What does lithification mean?

A

The process by which loose sediments are transformed into solid rock, critical in formation of sedimentary rocks

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

What happens to waves in bays?

A

The behaviour of waves in bays is influenced by the bay’s specific characteristics, including its shape, depth, and the presence of coastal features

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

What is threatening the Holderness Coast?

A

Rapid coastal erosion due to soft geological formation, lack of coastal defences, high erosion rate due to strong waves from the north sea, and sea level rise.

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

What are the three major inputs influencing cliff formation?

A

Geological structure - Different types of rocks have varying resistance to weathering and erosion.
Folding and faulting -As a result of earth movements all rocks exhibit some degree of folding which can become weaknesses, creates lines of weakness which can be exploited.
Coastal morphology - On an indented coastline, headland sand the offshore topography concentrate wave attack on the headland by the process of wave refraction.

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

Abandon the line

A

the strategic withdrawal of human occupation in areas of high risk

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

Accretion

A

the accumulation of marine sediments

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

Advance the line

A

Active intervention to produce a defence line that is seaward of the existing line

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

Arch

A

A raised area when two caves erode back to back on a headland
e.g. Durdle Door

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

Backwash

A

movement of water back towards the sea after a wave has been broken

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

Bar

A

Coarse grained deposit of sediment extending across the mouth of the bay

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

Berm

A

Low hill of sand or gravel that forms at the upper limit of the swash

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

Beach nourishment

A

sand and shingle brought from elsewhere are added to beaches to maintain depth to protect from erosion in a natural way

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

Char

A

An island formed from silt deposit in a delta, the land is about at sea level and is very fertile, however easily washed away

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

Constructive waves

A

Low frequency 6-8 per minute waves with elliptical water motion, powerful swash and weak backwash

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

Concordant geology

A

The alignment of bands of alternate geology that run parallel to the coastline

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

Corrasion

A

Erosion by friction in load of contact with banks and bed

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

Deltas

A

Form when the amount of sediment delivered at the mouth of a river exceeds the amount removed by waves

28
Q

Destructive waves

A

High frequency 13-15 per minute waves with circular water motion, with weak swash and strong backwash

29
Q

Differential erosion

A

Varying rates of erosion relating to geology

30
Q

Discordant geology

A

Coasts which cut across the rock structure

31
Q

Diurnal range

A

The difference between the lowest temperature and the highest temp in a 24 hour period

32
Q

Eustatic

A

Changes in sea level caused by variations in water levels in the ocean

33
Q

Fiord

A

Very deep U shaped estuaries formed by drowning of glaciated valleys

34
Q

Gabion

A

cages enclosing rocks to defend the coast

35
Q

Geo

A

Steep sided narrow inlet

36
Q

Groyne

A

Posts with boards which run at right angles to the coastline which trap sediment drifting along the shore

37
Q

Hard engineering

A

Structures developed to protect the foot of cliffs and prevent erosion

38
Q

High energy coast

A

Coasts in which wave power is strong for a significant part of the year

39
Q

Hold the line

A

taking action to maintain the current defence line

40
Q

Isostatic

A

Change in sea level resulting from the rise and fall of land masses

41
Q

Isthmus

A

A narrow piece of land connecting two larger pieces of land

42
Q

Littoral zone

A

Extends from the high water mark to shoreline areas that are permanently submerged

43
Q

Low energy coasts

A

coasts in which wave power is weaker, low fetch, few gales enclosed and therefore sheltered

44
Q

Plagioclimax

A

where succession is stunted by human interference

45
Q

Psammosere

A

Succession of stages of plant growth forming colonisation of bare sand to climax vegetation

46
Q

Return period

A

average time between occurrences of a given event

47
Q

Saltation

A

Sand bounces across the surface of the beach blown by wind

48
Q

Slumping

A

Triggered by undercutting at the base of cliffs with rotation in the slip plane

49
Q

Spit

A

Long ridges of sand and shingle attached to land at one end

50
Q

Spring tide

A

Particularly high or low tides caused when the sun, moon and earth all lie in a straight line, happens twice a month

51
Q

Stack

A

A residual post of rock resulting from the continued erosion of arches

52
Q

Surges

A

Changes in water level as a result of meteorological forcing

53
Q

Swell

A

a circular motion caused by wind in sea as a wave reaches the shore

54
Q

tidal bore

A

in narrow estuaries the effect of tides can be more pronounced

55
Q

Tombolo

A

Shingle ridge linking the mainland to an island

56
Q

What can you say about low energy environments and deposition

A

Deposition occurs when there is insufficent energy to push the sediments further
- In low energy environments, factors such as wave and wind direction, the supply of sediment and the depth of water are often significant.

57
Q

What is the maximum tidal range for large depositional landforms?

A

3 meters

58
Q

What is a “swash aligned” beach? (Deposition)

A

Forms when waves break parallel to the coast. Creates bay beaches (Dorset coast) and barrier beaches, like Start Bay (Devon)

59
Q

What is a “Drift aligned” beach? (Deposition)

A

When LSD moves material down the coast producing a range of partly detached features. Such as spits.

60
Q

How are sand dunes formed? (Deposition)

A

When dry material from flat, open beaches is blown inland. Dunes migrate and a succession of plants colonise and adapt to this environment forming a dune or psammosere ecosystem.

61
Q

How are mudflats and salt marshes formed? (Deposition)

A

Formed of finer material which flocculates (sticks together) in the shallow water of estuaries. Plants here adapt to salt water and tidal conditions

62
Q

What is beach drift?

A

Swash processes caused by longshore currents may move material laterally along the shoreline

63
Q

What are beach susps?

A

Material at the top of the beach is of a larger calibre and supports steeper concave slopes, beach cusps occur where this coarser material is absorbing wave swash.

64
Q

How are bay head beaches developed (Deposition)

A

They build up in the sheltered, low energy environments of coves.Wave refraction focuses erosion on the surrounding headlands and so encourages deposition in the bay.

65
Q

why are drift aligned beaches more of an open system?

A

Sediment enters at one end, passes along the length of the beach due to LSD and then leaves the beach at the other end. the predominant angle of wave approach brings with it enough energy to keep the sediment moving

66
Q

What are the 4 criteria for a spit to form?

A
  • Ready supply of sediment, particularly sand and shingle
  • LSD is active
  • The coast has an abrupt change in direction, such as at an estruary or bay
  • Tidal range is limited (<3 metres)

Geography (10 decks)

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