Coastal processes

Question 1

The size and energy of the wave depends on certain factors:

Answer 1

The fetch (how far the wave has travelled)
The strength of the wind
How long the wind has been blowing for.

Question 2

What are the two types of wave?

Answer 2

Constructive and destructive

Question 3

Water that is rushed up the shore is known as..

Answer 3

Swash

Question 4

The water that flows back towards the sea is known as…

Answer 4

Backwash

Question 5

What are the 6 characteristics of Destructive waves?

Answer 5

Weak swash and strong backwash
Occurs in stormy conditions, with strong winds
The strong backwash removes sediment from the beach
The waves are steep and close together
Tall waves with short wavelength
High frequency (arriving quickly)

Question 6

What are the 6 characteristics of constructive waves?

Answer 6

Small waves, with low wave height and long wavelength
Occurs in calmer conditions, less wind
Strong swash and weak backwash
The strong swash brings sediments to build up the beach
Backwash is not strong enough to remove sediments
Waves are low and further apart.

Question 7

What are the three types of weathering?

Answer 7

Freeze thaw, biological and chemical.

Question 8

How does freeze thaw weathering occur?

Answer 8

This happens when rock is porous (contains holes) or permeable (allows water through)

Question 9

What is freeze thaw weathering?

Answer 9

Water enters cracks in the rock.
when temps drop the water freezes and expands, causing the crack to widen.
The ice melts and water makes it way deeper in the cracks.
The process repeats itself until the rock splits entirely.

Question 10

What is biological weathering?

Answer 10

Plant roots can get into small cracks in the rock.
As the roots grow, the cracks become larger.
This causes small pieces of rock to break away.

Question 11

How does chemical weathering occur?

Answer 11

Rainwater and seawater can be a weak acid. Rocks like limestone and chalk can, over time, dissolve by the acid in the water.

Question 12

What is mass movement?

Answer 12

Mass movement is the downhill movement of sediment that moves because of gravity.

Question 13

What are the four types of mass movement?

Answer 13

Rockfall, mudflow, landslide or rotational slips.

Question 14

What is rockfall?

Answer 14

Bits of rock fall off the cliff fave, usually due to freeze-thaw weathering.

Question 15

What is mudflow?

Answer 15

Saturated soil (soil filled with water) flows down a slope.

Question 16

What is landslide?

Answer 16

Large blocks of rock slide downhill

Question 17

What is a rotational slip?

Answer 17

Saturated soil slump down a curved surface.

Question 18

What are the four processes of erosion?

Answer 18

Hydraulic action, abrasion, attrition, solution.

Question 19

What is erosion?

Answer 19

Erosion is the wearing away of rock along the coastline, destructive waves are responsible for erosion on the coastline.

Question 20

What is hydraulic action?

Answer 20

The sheer power of the waves as they smash against the cliff. Air becomes trapped in the cracks in the rock and causes the rock to break apart.

Question 21

What is abrasion?

Answer 21

Pebbles grind along a rock platform, much like sandpaper. Over time the rock becomes smooth.

Question 22

What is attrition?

Answer 22

When rocks that the sea is carrying knock against each other. They break apart to become smaller and more rounded.

Question 23

What is solution?

Answer 23

The sea water dissolves certain types of rocks. In the UK, chalk and limestone cliffs are prone to this type of erosion.

Question 24

What are the five stages to wave cut notches/ platforms?

Answer 24

The cliff retreats, weather weakens the cliff, notch increases and cliff collapses, waves cut notch, wave cut platform.

Question 25

What is transportation?

Answer 25

Sediment carried by the waves along the coastline.

Question 26

What is the movement of material in waves referred to as?

Answer 26

Longshire drift.

Question 27

Waves approach the coast at an angle because….

Answer 27

Of the prevailing winds

Question 28

What is longshire drift?

Answer 28

Waves approach the coast at an angle due to prevailing wind, the swash carries material towards the beach at an angle. The backwash then flows back to the sea, down the slope of the beach. The process repeats itself along the coats in the zig-zag movement.

Question 29

What are the four types of transportation?

Answer 29

Solution, suspension, saltation and traction.

Question 30

What is solution?

Answer 30

When minerals in rocks like chalk and limestone are dissolved in sea water and then carried in solution. Not visible.

Question 31

What is suspension?

Answer 31

Small particles such as silts and clays are suspended in the flow of the water.

Question 32

What is saltation?

Answer 32

Where small pieces of shingle or large sand grains are bounced along the sea bed.

Question 33

What is traction?

Answer 33

Where pebbles and larger material are rolled along the sea bed.

Question 34

What is deposition?

Answer 34

When the sea loses energy, it drops the material is has been carrying. This is deposition.

Question 35

Deposition can occur on coastlines that have ___________ waves.

Answer 35

Constructive

Question 36

What are the four factors leading to deposition?

Answer 36

Waves starting to slow down and lose energy.
Shallow water.
Sheltered areas, e.g bays.
Little or no wind.