Coasts

What are the 4 characteristics of a wave cut platform?

- Gently slope down to the sea at an angle of 3-4 degrees. - Covered at high tide and are exposed at low tide. - Bare rock smoothed by abrasion. - Deep cracks in some places, with rock pools.

Under what conditions does coastal deposition occur?

- When waves enter an area of shallow water - When waves enter a sheltered area - When there is little wind - When a river or estuary flows into the sea reducing wave energy.

What is the typical frequency of destructive waves per minute?

10 - 14

Which type of erosion involves waves hitting the base of a cliff leading to air compression in cracks, causing repeated changes in air pressure. As air rushes out of the crack when the wave retreats it leads to an explosive effect as pressure is released.

Hydraulic action

Identify the main types of coastal erosion

Hydraulic action, abrasion, corrosion, attrition and solution.

What type of chemical weathering involves acidic rainwater breaking down rock, causing it to rot?

Hydrolysis

True or false?waves are caused by the transfer of energy from the wind to the sea due to the friction of the wind on the surface of the water.

True

True or False? Weathering can cause cliff instability, leading to mass movement.

True.

Under which condition will the rate of erosion be higher?

When coastlines are exposed to a large fetch, strong winds and a coastline with a narrow beach.

What is coastal deposition?

When waves drop and leave behind the load they were transporting.

What causes waves?

Wind

How is wave length calculated?

The distance between the 2 wave crests

Where does most marine load originate from?

The seabed

What is coastal erosion?

The wearing away and removal of material by waves.

Which type of coastal transportation involves large pebbles and boulders being rolled along the sea floor?

Traction

True or False? The direction of longshore drift is determined by the prevailing wind

True

What is the typical frequency of constructive waves per minute?

8 - 10

What is a headland?

A cliff that juts out into the sea that is surrounded by water on three sides.

What is a concordant coastline?

A coastline where alternating lays of hard and soft rock run parallel to the shore.

What is a wave cut platform?

A large expanse of flat rock visible at the base of a cliff.

What does a wide sandy beach show?

A large tide range.

Which type of erosion involves waves containing sand and larger fragments wearing away the base of a cliff or headland?

Abrasion

Which type of erosion involves waves causing rocks and pebbles to bump into each other and break up?

Attrition

A wave rushing back down towards the beach is called:

Backwash

What type of weathering involves carbonic acid in rainwater reacting with calcium carbonate in limestone to form soluble calcium bicarbonate that can be carried away in solution?

Carbonation

Which of the following are examples of chemical weathering?

Carbonation, hydrolysis and oxidation.

What type of weathering involves rainwater decomposing rock?

Chemical weathering

Which type of wave is most common in summer?

Constructive waves

What type of waves build beaches?

Constructive waves.

What type of erosion involves destructive waves picking up beach material and hurling them at the base of a cliff?

Corrosion

Identify the correct sequence in the formation of a stump.

Crack, cave, arch, stack, stump

What is the top of a wave called?

Crest

What is the characteristic of a stack?

Detached blocks or pillars or rock located off the headland.

Which coastline are headlands and bays normally found?

Discordant

What is the typical characteristic of a pebble beach?

Dominant waves are constructive

True or False? A landslide involves individual rocks losing contact with the life face, often as the result of freeze-thaw.

False

True or False? Mechanical weathering involves rocks being disintegrated rather than decomposed and is usually associated with extreme temperatures?

False

Which of the following are examples of mechanical weathering?

Freeze-thaw and salt weathering

What causes the wave to slow as it approaches a beach?

Frictional drag.

What is the zig-zag movement of transported material along the coast known as?

Longshore drift

What type of chemical weathering involves rocks being broken down by oxygen and water?

Oxydation

Which of the following are examples of mass movement?

Rockfall, landslide, mudslide and slumping

Which type of coastal transportation involves beach material being bounced along the seabed?

Saltation

What are the large heaps of sand that form on the dry back shore of a sandy beach know as?

Sand dunes

Where are constructive waves typically found?

Sheltered bays.

Which type of mass movement features a concave slip pane?

Slumping

Which type of erosion involves certain types of cliff eroding as the result of weak acids in the sea?

Solution.

Which type of coastal transportation involves dissolved material being carried by the water?

Solutions

Which type of coastal transportation involves being suspended and carried by the waves?

Suspension

What is it called when a wave breaks on a beach and washes up it?

Swash

What are the characteristics of a destructive wave?

The backwash is stronger than the swash.The wave height is high.

What is the characteristic of a stump?

The base of a collapsed stack

What happens to a beach when a waves backwash is stronger than the swash?

The beach is eroded.

What is weathering?

The breaking down of rock.

What is the fetch of a wave?

The distance a wave travels.

What is mass movement?

The down-slope movement of rock, soil or mud under gravity.

What is beach profile?

The gradient from the back of the beach to the sea.

What is wave frequency?

The number of waves breaking per minute.

What influences the size and energy of a wave?

The strength of the wind, how long it has been blowing for and the fetch.

What are the characteristics of a constructive wave?

The swash is stronger than the backwash.The wave height is low.

Why are some waves stronger than others?

They have a long fetch and strong winds have been blowing them for a long time.

What are the 4 processes of coastal transportation?

Traction, satiation, suspension and solution.

What is the base of a wave called?

Trough

True or false? In deep water, water molecules within a wave move in a circular motion. It is only in the shallow water that the water itself is moving forward.

True

Why is wave energy concentrated on a headland?

Wave refraction

How is wave height calculated?

the distance between the trough and the crest.