Coasts

Question 1

What are coasts?

Answer 1

The name given for the zone between land and sea.

Question 2

What is a constructive wave?

Answer 2

A type of wave that builds up beaches, by depositing more material than it erodes away. They have a strong swash and weak backwash. It has a long wave length and a low wave height and frequency.

Question 3

What is a destructive wave (3pts)?

Answer 3

• A type of wave with a weak swash and strong backwash by eroding more material than it deposits.
• It has a short wave length and high wave height and frequency.
• It also has a crashing break because of its speed.

Question 4

What are bays?

Answer 4

A landform formed by erosion of softer rocks that erode inward to create a curve.

Question 5

What is deposition?

Answer 5

The process that involves beach material being dropped off (to create beaches) after it has been eroded and transported.

Question 6

What are prevailling winds?

Answer 6

The name given to the most common wind direction for a particular location (in England it is the South West).

Question 7

What is longshore drift?

Answer 7

Name of the process that carries material along the beach due to repeating movement of wave swash and backwash.

Question 8

What is backwash?

Answer 8

The process where waves run back down the beach, dragging material back with them.

Question 9

What are headlands?

Answer 9

The area of land left sticking out into sea as it has eroded slower than other areas.

Question 10

What is the fetch of the wave?

Answer 10

The distance the wave travels. The further it has travelled the more strength it will have.

Question 11

What are the 5 coastal processes?

Answer 11

Weathering, mass movement, erosion, transport, deposition.

Question 12

What is chemical weathering?

Answer 12

Also known as solution, occurs when acid rain falls onto the rock, causing it to dissolve and wear away.

Question 13

What is physical weathering?

Answer 13

Also known as freeze thaw weathering, is where a crevice in a rock is filled with water, the water then freezes, expanding by 9%, and the now enlarged crevice in the rock causes it to crack.

Question 14

What is biological weathering?

Answer 14

Occurs when seeds get into crevices and begin to grow roots in the rock, causing the rock to split apart.

Question 15

What is erosion?

Answer 15

The downhill movement of rock and soil under gravity. This can be fast (rock falls) or slow (landslides).

Question 16

What is transport?

Answer 16

The movement of material along the coast. Examples of this is the longshore drift.

Question 17

What is hydraulic action?

Answer 17

The force of the wave causes water and air to be forced into cracks in the rock, creating pressure and making the cracks wider. This mainly occurs in storms.

Question 18

What is corrosion/solution?

Answer 18

Salts and chemicals in the sea dissolve the rocks by touch, especially with limestone. Sea water is alkaline. Corrosion usually occurs in the intertidal zone where sea water and air affect the rock.

Question 19

What is abrasion?

Answer 19

The waves carry loose material and rocks which rubs against the cliffs like a sandpaper affect, causing it to smoothen and break down.

Question 20

What is attrition?

Answer 20

The sea picks up angular rocks and throws them together, causing the edges to be chipped away creating a smoother, smaller and rounder affect.

Question 21

Why do waves form?

Answer 21

They form from wind pushing the surface of the sea forward. The particles in waves move in small circles that get larger the further into sea they are.

Question 22

Why do waves break?

Answer 22

They break because of the friction of the sand on the particles in waves. It slows down the bottom of the wave, but the top keeps going over.

Question 23

What 3 factors cause some waves to be bigger than others?

Answer 23

Wind speed, wind duration and fetch.

Question 24

Why does wind speed affect the size of the wave?

Answer 24

The stronger the wind, the larger the wave because the surface of the sea will we pushed with more force.

Question 25

Why does the wind duration affect the size of a wave?

Answer 25

The stronger the wind acts on the sea, the larger the waves will be. This is because the wind has longer to manipulate the surface of the water.

Question 26

Why does the fetch affect the size of the wave?

Answer 26

It is the maximum distance over which waves can form, particularly where the wind blows in one direction. This affects the size of the wave because the longer time the wind has to act on the water, the larger the waves will be.

Question 27

What is the swash?

Answer 27

The movement of water going up the beach.

Question 28

What is a wave cut platform?

Answer 28

A sloping platform left behind as the cliff face erodes backwards.

Question 29

How sloped is the wave cut platform?

Answer 29

2 to 6 degrees downwards.

Question 30

Where is the low tide on a cliff?

Answer 30

A little further up the wave cut platform.

Question 31

Where is the high tide on a cliff?

Answer 31

At the top of the wave cut notch.

Question 32

What is the intertidal zone?

Answer 32

It is between low tide and high tide vertically.

Question 33

What is scree?

Answer 33

Piles of eroded rock.

Question 34

What is discordinate coastline?

Answer 34

Where bands of rock run perpendicular to the coastline.

Question 35

What is concordant coastline?

Answer 35

Where bands of rock run parallel to the coastline.

Question 36

What does fast longshore drift look like?

Answer 36

Very small angle between coastline and moving sedimentary.

Question 37

What is a coastal spit?

Answer 37

A protruding, long, narrow stretch of land made of deposited matter.

Question 38

How is a coastal spit formed (5pts)?

Answer 38

Longshore Drift: 1. Waves approaching the coast at an angle (due to prevailing winds) cause sediment to be moved along the beach. 2. Coastal Change: When the coastline changes direction (e.g., a bay, river mouth, or headland), the longshore drift continues past this point, carrying sediment further out to sea. 3. Deposition: As the coastline bends, the waves lose energy and deposit the carried sediment. 4. Spit Formation: This deposited material builds up, forming a long, narrow ridge of sand or shingle that extends out into the sea, connecting to the mainland at only one end. 5. Curved or Hooked End: Changes in wind or wave direction can cause the end of the spit to curve or develop a hooked shape.

Question 39

What is mass movement?

Answer 39

The downhill movement of soil and rock under gravity.

Question 40

What are the 4 types of mass movement?

Answer 40

Rockfall, mudflow, landslide and rotational slip.

Question 41

What is rockfall?

Answer 41

The movement of detached rock fragments, boulders, or large pieces of rock down a steep slope or cliff.

Question 42

What is mudflow?

Answer 42

A rapid downhill movement of saturated soil and debris. Occurs when soil becomes saturated by water, often by rain, and flows down a slope.

Question 43

What is a landslide?

Answer 43

It is a fast form of mass movement. It occurs on rocky coast, when large blocks of detached rock slide downhill on sloped cliffs.

Question 44

What is rotational slip?

Answer 44

Type of mass movement where saturated soil or rock slumps downwards along a curved or concave surface.

Question 45

What are the 3 options when trying to protect coastline?

Answer 45

Managed retreat, hold the line and advance the line.

Question 46

What is hard engineering?

Answer 46

The controlled management of coastal processes using man made structures.

Question 47

What is soft engineering?

Answer 47

Taking advantage of land and using natural processes to reduce erosion and achieve stabilisation and safety of shorelines.

Question 48

What are the types of hard engineering (4pts)?

Answer 48

- Groynes. - Sea walls. - Rock armour/rip rap. - Gabions.

Question 49

What are the types of soft engineering (2pts)?

Answer 49

- Beach recharge. - Managed retreat.

Question 50

How does a wave-cut platform form?

Answer 50

Where the hard rock is at the bottom because it is more resistant and soft rock erodes quickly forming sloping cliffs.

Question 51

How does a crack/notch form?

Answer 51

Fault opens in the rock and due to hydraulic action it grows bigger to form a notch.

Question 52

How does a cave form?

Answer 52

Both hydraulic action and abrasion widen the notch into a cave that keeps growing bigger.

Question 53

How does an arch form?

Answer 53

Due to waves and erosion, the cave opens through and forms an arch.

Question 54

How does a stack form?

Answer 54

The arch keeps widening and collapses, leading to a stack. It stands but is still being undercut.

Question 55

How is a stump formed?

Answer 55

Stack will eventually collapse leaving a stump.