Physical - Coasts

Question 1

Swash

Answer 1

The wave going into the beach

Question 2

Sand spit

Answer 2

A coastal feature created by the process of longshore drift. A long narrow ridge of sand or shingle that extends out to sea and is joined to the main land at one end.

Question 3

Backwash

Answer 3

The retreating wave

Question 4

Longshore drift

Answer 4

The movement of material along the coast in the direction of the prevailing wind

Question 5

Constructive wave

Answer 5

A low-energy wave that has a stronger swash than backwash creates beaches through coastal deposition

Question 6

Destructive wave

Answer 6

A high-energy wave that has a stronger backwash than swash, created during high wind. Erodes coast.

Question 7

Abrasion

Answer 7

Loose rocks (sediment) are thrown against the cliff by waves, wearing the cliff away by smoothing them like sandpaper

Question 8

Attrition

Answer 8

Rocks knock against each other, causing them to break apart and become more rounded

Question 9

Hydraulic action

Answer 9

Waves force water into cracks in the rock. This compresses the air in the rock, causing the rock to weaken and eventually break apart

Question 10

Solution

Answer 10

Salt and other chemicals in the sea dissolve soft rocks such as limestone and chalk

Question 11

Fetch

Answer 11

How far a wave has travelled

Question 12

Factors affecting the rate of coastal erosion

(2 points)

Answer 12

• Resistance of rock - the harder a rock is, the harder it is to be worn away so it will erode slower than soft rock
• Wave fetch - the further a wave has travelled the more force it has

Question 13

Headland

Answer 13

An area of hard rock extending into the sea

Question 14

Bay

Answer 14

An inlet between two headlands, usually formed by soft rock

Question 15

Formation of headlands and bays

(4 steps)

Answer 15

• Bands of alternating hard and soft rock meet the coast at right angles
• Differential erosion occurs as the sea erodes the softer rock faster than the harder rock, forming bays
• Where there is harder rock, headlands are left extending out beyond the bays
• The bays are sheltered by the headlands, which absorb the energy of the waves. This causes erosion to slow down in the bays and deposition occurs, forming a beach

To get full marks, 2 processes of coastal erosion must be mentioned (e.g. hydraulic action and abrasion)

Question 16

Formation of caves, arches, stacks, and stumps

(5 steps)

Answer 16

• Hydraulic action makes a small crack in a headland larger
• Continuous erosion opens up the crack, and it forms a sea cave
• Further erosion of the cave will eventually cause it to break through the headland, forming an arch
• Waves continue to erode the arch until the roof collapses, leaving behind a freestanding tower of rock called a stack
• The stack is continuously eroded until it eventually falls over, creating a stump

Question 17

Wave - cut notch

Answer 17

A notch in the base of a cliff, formed when a cliff is undercut by waves

Question 18

Wave - cut platform

Answer 18

A platform made of flat rock at the base of a cliff, formed when a cliff retreats

Question 19

Formation of a wave - cut platform

(4 steps)

Answer 19

• Erosion takes place where the waves hit the shore, forming a wave - cut notch
• The notch is further eroded to leave an overhang above
• Further erosion causes the overhang to collapse into the sea, leaving a cliff behind
• Continuous erosion causes the cliff to retreat inland, leaving a wave - cut platform behind

Question 20

Formation of a lagoon

(3 steps)

Answer 20

• When the coast changes direction, longshore drift continues to deposit sand in a straight line
• The sand will build up until it is above sea level, causing a sand spit to form
• When a sand spit forms across the mouth of a bay (only if there is no river), a sand bar is formed
• The pool trapped behind the sand bar goes stagnant and is called a lagoon

Sand spits can develop curved ends due to changes in wind direction

Question 21

Tombolo

Answer 21

When a spit joins an island to the mainland it is called a tombolo

Question 22

Cliff

Answer 22

Steep sided rock face

Question 23

Cave

Answer 23

Hollow in the side of a cliff

Question 24

Beach

Answer 24

Strip of sand and stones next to the sea

Question 25

Stack

Answer 25

Rocky pillar surrounded by water

Question 26

Arch

Answer 26

Hole passing right through a headland