Coasts Flash cards

?
How can the features of a coastline be made? (2 key processes)
1. Erosion 2.Deposition
1 of 38
What uses do we have of the coast line?
1. Living 2.Working 3.Leisure
2 of 38
What do we protect the coastline from?
1. Erosion 2. Transportation 3.Deposition
3 of 38
What are the erosional processes?
1. Corrosion 2.Corrasion 3.Attrition 4.Hydraulic Pressure
4 of 38
What is corrosion?
The chemical reaction of sea in the water and the rocks. (Limestone is particularly vulnerable)
5 of 38
What is corrasion?
When waves throw sand and pebbles at a rock face.
6 of 38
What is attrition?
When rocks and pebbles collide causing them to break off into small pieces.
7 of 38
What is hydraulic action?
Pressure of waves breaking the coastline
8 of 38
What are the 4 ways the sea transports material?
1.Traction 2.Saltation 3. Suspension 4. Solution
9 of 38
What is traction?
Where large boulders are rolled along the sea bed.
10 of 38
What is saltation?
Where smaller rocks are bounced along the sea bed
11 of 38
What is suspension?
Where smaller particles are carried along the water flow.
12 of 38
What is solution?
Where dissolved rock particles are carried along the water in solution.
13 of 38
How do waves move material?
Longshore drift
14 of 38
What is long shore drift?
Where waves approach a beach at an angle and move sand and shingle with them.
15 of 38
What does the direction of longshore drift depend on?
The direction of prevailing winds.
16 of 38
What hard engineering method is used to stop longshore drift?
Groynes: wooded fences that rundown from the beach into the sea.
17 of 38
How do groynes work?
They trap the material from being carried downshore by the waves and redistribute material by replenishing the beach.
18 of 38
What are the two types of waves?
1. Constructive 2.Destructive
19 of 38
What do constructive waves do? How?
Help to build beaches as they have a stronger swash to backwash movement. This swash pushes material up the beach.
20 of 38
What do destructive waves do? How?
They have a stronger backwash which drags the material off the beach and into the sea.
21 of 38
When do waves deposit the material they are carrying?
When waves have less energy.
22 of 38
What are some of the features caused by coastal erosion?
1. Cliffs. 2.Caves 3. Arches 4.Stacks 5.Stumps
23 of 38
How are sea cliffs formed?
When waves erode the base between high and low tide creating a wave cut notch. This continues to erode until the material above can no longer be supported this falls into the sea and then gets transported away by destructive waves.
24 of 38
How are sea caves formed?
Waves erode a vulnerable part of the headland creating a gap.
25 of 38
How are arches formed?
Sea caves get eroded further until they break through the headland creating an arch.
26 of 38
How are stacks formed?
Arches continue to be eroded until they are so wide that they can no longer support the above material causing it to collapse. The pillar that is left is called a stack.
27 of 38
How are stumps formed?
The stack gets eroded at the base until is eroded into the sea creating a stump.
28 of 38
How are beaches formed?
Constructive waves deposit material where they lack energy for example in a sheltered areas.
29 of 38
Why are beaches not permanent features?
They are constantly being changed by longshore drift.
30 of 38
What two materials can beaches be formed by?
1. Sand 2.Shingle
31 of 38
What is a spit?
It is a permanent land feature which is attached to the land that goes out into the sea.
32 of 38
How are spits formed?
It is formed by coastal deposition where longshore drift moves constructive waves along the coastline but then the coastline changes direction material is deposited until it becomes above sea level.
33 of 38
Why will a spit not grow across a river estuary?
Because the force of the river does not allow material to be deposited.
34 of 38
How are bars formed?
When the spit gross across the bay to form a bar
35 of 38
Where are salt marshes formed?
Behind a spit. Or when a lagoon behind a bar becomes a salt marsh.
36 of 38
What is a tombolo?
A ridge of deposited sand or shingle which joins and off shore island with the main land.
37 of 38
Why are tombolos formed?
An offshore island will cause wave refraction resulting in material being deposited by longshore drift.
38 of 38

Other cards in this set

Card 2

Front

What uses do we have of the coast line?

Back

1. Living 2.Working 3.Leisure

Card 3

Front

What do we protect the coastline from?

Back

Preview of the front of card 3

Card 4

Front

What are the erosional processes?

Back

Preview of the front of card 4

Card 5

Front

What is corrosion?

Back

Preview of the front of card 5
View more cards

Comments

No comments have yet been made

Similar Geography resources:

See all Geography resources »See all Sustainability resources »