Coastal systems and processes

Question 1

Main source of energy at a coast

Answer 1

Waves

Question 2

Three factors affecting how much energy a wave has

Answer 2

Fetch, strength and duration.

Question 3

Fetch

Answer 3

The distance of open water the wind blows over.

Question 4

Strength

Answer 4

How forceful the wind is, determined by the pressure difference.

Question 5

Duration

Answer 5

How long the wind has been blowing.

Question 6

Tide and Tidal range

Answer 6

Tide is the changes in the level of water due to gravitational pull of the moon.
Tidal range = difference in height between high and low tide.

Question 7

Constructive waves

Answer 7

Short fetch, long wavelength, low waves, strong swash, weak backwash.

Question 8

Destructive waves

Answer 8

High fetch, short wavelength, high waves, weak swash and strong backwash,

Question 9

Wave refraction

Answer 9

Changes the amount of energy reaching the shore on a small local scale.

Question 10

Sediment budget

Answer 10

The balance between the inputs and outputs of sediment in the system, should be in dynamic equilibrium, natural changes like climate change can disturb this however.

Question 11

Weathering

Answer 11

The breakdown of rock in its place of origin. (in-situ)

Question 12

Three main types of weathering.

Answer 12

Physical/mechanical weathering, chemical weathering and biological weathering.

Question 13

Mechanical/physical weathering

Answer 13

When rocks break up with no chemical changes

Question 14

Freeze-thaw weathering (physical/mechanical)

Answer 14

Question 15

Salt crystallisation (mechanical/physical weathering)

Answer 15

Question 16

Biological weathering

Answer 16

Question 17

Three methods of chemical weathering

Answer 17

Carbonation, Oxidation and solution

Question 18

(ChemW) Carbonation

Answer 18

When rain is slightly acidic and reacts with carbonate rocks like limestone, causing them to dissolve.

Question 19

(ChemW) Oxidation

Answer 19

When iron minerals in the rock react with oxygen in the air to cause rusting and breakdown the rock.

Question 20

(ChemW) Solution

Answer 20

When other salt minerals in the rock are dissolved.

Question 21

Mass movement

Answer 21

The downhill movement of material under the influence of gravity.
Including landslides, slumping and rockfalls.

Question 22

Hydraulic action

Answer 22

Erosional processes that occur due to the power of the waves, with no involvement of the rocks at all.

Question 23

Abrasion

Answer 23

Occurs when breaking waves that are carrying sediment scrape against the rock surface.
Also known as corrasion.
Dependant on how much sediment is available in the particular coastal system

Question 24

Attrition

Answer 24

When the size of sediment particles change as sediment held in the waves rub together.

Question 25

Solution/corrosion

Answer 25

Acids in the seawater wear away the rock.

Question 26

Marine transportation

Answer 26

Material in the water is moved in 4 ways:
Traction, Saltation, Suspension, Solution.

Question 27

(MarTrans) Traction

Answer 27

Traction is when pebbles and larger material is rolled along the sea bed.

Question 28

(MarTrans) Saltation

Answer 28

Saltation is when small pieces of shingle or large sand grains are bounced along the seabed.

Question 29

(MarTrans) Suspension

Answer 29

Suspension along the coast is when small material such as clay or silt are held in the flow of the seawater.

Question 30

(MarTrans) Solution

Answer 30

Weak carbonic acid in seawater dissolves minerals in rocks which are then carried in solution.

Question 31

Longshore drift

Answer 31

Main process of deposition and transportation along the coast.
Influenced by the prevailing wind, waves approach the beach at an angle.