(B) Coastal Landscapes

Question 1

What is marine erosion

Answer 1

The removal of material be waves

Question 2

3 types of marine erosion

Answer 2

Hydraulic action
Abrasion/corrasion
Attrition
Solution

Question 3

What is hydraulic action

Answer 3

The force of waves against rocks

Question 4

What is abrasion/corrasion

Answer 4

The force of material against rocks

Question 5

What is attrition

Answer 5

The force of load particles colliding with each other

Question 6

Examples of when rate of erosion is higher

Answer 6

Coastline exposed to large fetch
Jutting headland
Softness of rocks

Question 7

Characteristics of constructive waves

Answer 7

Height - Under 1m
Shape - long
Swash- strong
Backwash - weak
Number per min - 8-10
Effect on beach - build it up
Typical season - summer

Question 8

Characteristics of destructive waves

Answer 8

Height - over 1m
Shape - short
Swash- weak
Backwash - strong
Number per minute - 10-14
Effect on beach - drags material away
Typical season - winter

Question 9

Headland definition

Answer 9

Cliff that just out to sea surrounded by water on 3 sides

Question 10

Bay definition

Answer 10

Crescent shaped indentation in the coastline between 2 headlands

Question 11

Where do bays and headlands form

Answer 11

Where there are alternate bands of resistant and less resistant rock

Question 12

Types of erosion to create bays and headlands

Answer 12

Hydraulic action

Abrasion/ corrasion

Question 13

Cliff definition

Answer 13

A steep or vertical face of rock often found at a coast

Question 14

Wave cut platform definition

Answer 14

A wide gently sloping rocky surface at the foot of a cliff

Question 15

How are waves cut platforms formed

Answer 15

Destructive waves hit the cliff face to cause undercutting as a result of corrasion and hydraulic action
This cause a wave cut notch and so the cliff falls
As the cliff retreats a wave cut platform is left

Question 16

Recall caves, arches, and stacks

Answer 16

• Cracks appear In headland
• Becomes eroded and breaks to form a cave
• Continues to erode to form an arch
• Arch collapses and leaves a stack
• Breaks and causes a stump

Question 17

Beach definition

Answer 17

A landform of coastal deposition that lies between the high and low tide levels

Question 18

Sandy beach characteristics

Answer 18

Gradient: Almost flat
Dominant wave: Constructive
Distance stretch inland: Long
Back of beach: Sand dunes
Other: Runnels form at low tide

Question 19

Pebble beach characteristics

Answer 19

Gradient: Steep
Wave type: Destructive
Distance stretch inland: Short
Beach of beach: Storm beach (large pebbles)
Other: Pebbles increase in size further back

Question 20

What is a berm and where are they mainly found

Answer 20

A terrace on a beach formed when sand/shingle is slowly moved up a beach by successive incoming tides.
Found at the back of shingly beaches

Question 21

What are runnels and where are they found

Answer 21

Channels that allow drainage when tides are low

On a sandy beach

Question 22

What are sand dunes

Answer 22

Large heaps of sand, form on dry backshore of sandy beaches

Question 23

What do sand dunes need to form

Answer 23

• large flat beach
• supply of sand
• large tidal range so there is time for sand to dry
• on shore wind
• obstacle for dune to form against

Question 24

Describe formation of sand dunes

Answer 24

• sand continues to move up the windward slope
• height builds until structure is unstable
• sand then slips down the leeward side

Question 25

Characteristics of sand dunes

Answer 25

• gentle slope on windward side
• crests
• unstable steep slope on leeward side

Question 26

6 types of dune in order

Answer 26

Embryo dune
Fire dune
Yellow dune
Grey dune
Dune slack
Mature dune

Question 27

What is dune slack

Answer 27

Where there is a trough or low point in a line of dunes

Question 28

What is a leeward slope

Answer 28

Slope facing away from wind

Question 29

What is windward slope

Answer 29

The slope facing the wind

Question 30

3 processes in which sand moves

Answer 30

Suspension
Saltation
Creep

Question 31

What is suspension

Answer 31

Sand is picked up and carried by wind (1%)

Question 32

What is saltation

Answer 32

Sand bounces along as the wind picks it up and drops it (95%)

Question 33

What is creep

Answer 33

Sand collides with each other and push other grains along

4%

Question 34

3 ways load is transported on to a beach

Answer 34

Traction
Suspension
Saltation

Question 35

How is load transported along a beach

Answer 35

Long shore drift

Question 36

What determines the direction of longshore drift

Answer 36

The prevailing wind

Question 37

When does deposition mainly occur

Answer 37

Low energy waves
Sheltered bays
Constructive waves
Flat beach
Large source of sediment
Engineered structures trap sediment

Question 38

What is a spit

Answer 38

An area of sand or shingle which extends at a gentle angle out to sea or which grows across a rice estuary.
May have a hooked or curved end

Question 39

Requirements for spit to form

Answer 39

• longshore drift
• sudden change in direction of coastline
• relatively shallow sea
• possible more sheltered sea

Question 40

Formation of a spit

Answer 40

Material is carried via longshore drift
A change in the direction of the coastline causes a sheltered area to form
Shallow water means that it loses energy and deposits material
Prevailing wind causes spit to curve inward forming a hook
Salted marshland forms behind the spit