1. Coastal Landscapes
Aims:
• To know how the coastline is shaped.
• To understand the different types of wave
and their characteristics.
• To be able to explain the different types of
weathering, erosion and mass-movement.
2.
3. The coast is under attack through a
variety of processes:
• Erosion
• Weathering
• Mass-movement
6. Attrition
Material carried by the waves bump into each other and so
are smoothed and broken down into smaller particles.
Hydraulic Action
This process involves the force of water against the coast.
The waves enter cracks (faults) in the coastline and
compress the air within the crack. When the wave
retreats, the air in the crack expands quickly causing a
minor explosion. This process is repeated continuously.
Corrosion
This is the chemical action of sea water. The acids in the
salt water slowly dissolve rocks on the coast. Limestone
and chalk are particularly prone to this process.
Abrasion/Corrasion
This is the process by which the coast is worn down by
material carried by the waves. Waves throw these
particles against the rock, sometimes at high velocity.
7. Weathering is the natural breakdown of
rocks at the earth’s surface.
Using Geographical Foundations pgs 57-
58.
Task:
1. Describe and explain the 3 main types
of weathering.
2. What is mass-movement?
3. What are the different types?
8. What affects the rate of
coastal erosion?
Waves are the main agents of erosion at
coastlines. Wave action and power
depends upon different factors.
What factors affect waves?
9. Why are waves generally larger in the south
west than in the south east?
Wave energy depends on the
fetch, the strength of the
wind and the length of time
over which the wind has
blown.
fetch = the distance over
which the wind has blown
Complete Activity 1 on pg 57.
10. Waves can either be…
Destructive waves Constructive waves
Tasks:
1. Copy the diagrams of figure 1 and figure 2 on
page 56.
2. Describe how these waves are different and
add a summary using page 57.
11. Breaking waves cause two
movements:
• Swash moves up
the beach
• Backwash moves
straight down the
beach
12. Swash and backwash
Backwash
Swash
Remember: Backwash is always at right angles to the beach!
13. Constructive Waves
Spilling Breaker
Powerful Swash
h
ackwas
W eak B
DEPOSITS MATERIAL
14. Destructive Waves
Crashing breaker
sh
Weak swa
Powerful Backwash
ERODES MATERIAL
