Topic 4

Question 1

What is the rock type on a concordant coastline?

Answer 1

Only hard rock such limestone

Question 2

Features of a concordant coastline are…

Answer 2

Cliffs and coves

Question 3

Rock type on a discordant coastline is…

Answer 3

Repeating strips (strata) of hard then soft rock. At a right angle to the sea

Question 4

Features of a discordant coastline

Answer 4

Headlands (hard rock) and bays (soft rock), arch stack stumps

Question 5

Example of concordant coastline

Answer 5

Dorset Durlston head-kimmeridge

Question 6

Example of discordant coastline

Answer 6

Dorset poole harbour-durlston head

Question 7

What are joints and faults and how do they effect erosion

Answer 7

They’re weak points in the rock such as a crack and can speed up erosion through processes such as hydraulic action

Question 8

Example of soft rock

Answer 8

Clay, sandstone, chalk

Question 9

Examples of hard rock

Answer 9

Slate, granite, marble

Question 10

Characteristics of headlands

Answer 10

Cliffy, rocky, no beach- waves crash into cliffs. Higher waves

Question 11

Characteristics of bays

Answer 11

Lower energy waves, beaches, set further back than headland

Question 12

Explain formation of headlands and bays

Answer 12

Strata of soft rock and hard rock parallel to sea waves. Waves continuously crashing in. Soft rock erodes back quicker than hard rock through processes such as abrasion, hydraulic action etc. Headland is formed when soft rock either side eroded backwards. Sediments fall from headland and end up on bay forming a beach

Question 13

Characteristics of wave cut platforms

Answer 13

…

Question 14

How are wave cut platforms formed

Answer 14

Intertidal area is eroded the most. Cliff becomes unsupported after rock below being eroded and overhangs the wave cut notch. Cliff then falls, retreats and the process begins again

Question 15

Characteristics of arch stack stumps

Answer 15

Rocky,steep, high

Question 16

How are arch stack stumps formed

Answer 16

Large weakness forms in rock. base of the crack erodes through hydraulic action. This gets larger and forms a cave. The cave forms an arch when it erodes through the headland. The arch keeps getting eroded until the roof is no longer supported. This forms a stack. This stack is eroded by waves until it tips over and firms a stump

Question 17

3 factors that effect wave energy

Answer 17

Fetch, wind speed, gradient of seabed.

Question 18

Where in the UK has the biggest wave

Answer 18

East coast and north coast of scotland because of very large fetch

Question 19

Compare constructive and destructive for wavelength and frequency

Answer 19

Constructive have longer wave length and lower frequency than destructive

Question 20

Compare con and destructive waves for swash and backwash

Answer 20

Constructive has more swash to transport sediments onto the beach and destructive has more backwash to take sediments away. Destructive have more erosional power

Question 21

Explain rotational slumping

Answer 21

When the force of gravity is greater than the force holding it up the cliff collapses. Usually when lubricated by rainfall. A slump is when the cliff collapses through a rotational turn

Question 22

Compare biological, freeze thaw and chemical weathering

Answer 22

Biological is naturally such as a plant putting its roots in a crack and expanding. Freeze thaw is the process of water entering cracks, expanding in cold temperatures as it freezes then melting and contracting again and chemical weathering is when rain is made slightly acidic which reacts with calcium in chalk and causes it to erode

Question 23

Abrasion

Answer 23

When sediments get thrown against the cliff by waves constantly. Eventually chipping bits away

Question 24

Hydraulic action

Answer 24

When salt water enters the cracks and the salt in the water expands and pushes the crack wider and wider multiple times until it cracks off

Question 25

Attrition

Answer 25

Sediments in the waves crash into each other and become smaller and smoother

Question 26

Solution

Answer 26

When sea water dissolves certain types of rock such as chalk

Question 27

What is traction

Answer 27

Boulders rolling along the sea bed because they’re too heavy to be lifted by the waves

Question 28

What is saltation

Answer 28

Small pebbles ‘bouncing’ along the sea bed

Question 29

Suspension

Answer 29

Small pebbles essentially floating in the water being moved along by the wave energy

Question 30

Solution

Answer 30

Really small sediments essentially float through the water without being seen

Question 31

Explain LSD

Answer 31

Waves travel in the prevailing wind direction. These transport sediment which hit the coast at an angle through swash. They then return at a 90° angle through backwash. This is repeated

Question 32

How are spits formed

Answer 32

They form at sharp curves in the coastline LSD transport sediments past the coast onto the sea. The sheltered area behind the spit are protected from waves

Question 33

How does coastal management (building groynes for example) affect coastlines down drift?

Answer 33

It creates mass erosion to other beaches (bays) as the rock is deposited there

Question 34

2. How does agriculture affect the coastline

Answer 34

It could softer the land therefore is easier to erode/erodes easier

Question 35

4. How does industry affect the coastline?

Answer 35

Most of the sand is used to give height to industries therefore bays are much steeper, meaning waves are more destructive

Question 36

5. How does coastal management affect the coastline?

Answer 36

Groynes cause faster erosion and are very expensive. Which are also hard to maintain and they dig the sand from under the sea making the waves more powerful and destructive