Transcript Document
Teach me, Tell Me
How are coasts shaped by physical processes?
You have been given a key word with a definition on it.
1. You must quiz one person to define the key term.
2. Congratulate them on a correct definition or correct their
response.
3. You are then quizzed by them in the same way.
4. Swap cards
5. Move on to a new person and repeat the process
VERY QUICKLY YOU WILL KNOW ALL THE PROCESSES!!
1.
2.
3.
4.
What is swash?
What is backwash
Which of diagram below is a destructive wave?
What do we call the other type of wave?
What is happening on the destructive
piece of coastline?
What is happening on the constructive
piece of coastline?
The impact of geology on coastlines
Rock type and structure can have a significant impact on coastal
landforms. More resistant rocks such as chalk and limestone are eroded
more slowly. Weaker rocks such as clays and sands are frequently
weakened by heavy rainfall and marine erosion. The effect geology can
have on coastal landforms can be seen on the Dorset coast.
Make the
shape of
this
coastline
out of
Playdough.
What type of
coastline is this?
Discordant
What type of
coastline is this?
Concordant
Features on a Discordant coastline – Dorset
1. Erode soft rock away
2. You have made 2 bays (Studland and Swanage)
3. The hard rock left is called a headland (Ballard
Point)
4. Destructive ways start to attack headlines on
both sides
http://www.youtube.com/watch?
v=RTyOTaOsp_U
5. A crack is widened by hydraulic action and
abrasion
6. Continued erosion turns a notch into a sea cave
7. Continued erosion of sea caves on either side of
the headland forms an arch
8. Due to weathering and instability the arch
collapses and leaves a stack
9. Continued erosion of the stack leaves a stump.
10. You have just made Old Harry Rocks
Depositional features
1. Why do we get the formation of spits?
2. What is it called if a spit joins the mainland to an island e.g. Chesil Beach Dorset to the Isle of
Portland?
Conveyor Learning
Physical reasons the
coastline needs to be
protected
Human reasons the
coastline needs to be
protected
Hard engineering
methods
Soft engineering
methods
1. With the use of example explain why an area of coastline needs to be
protected and the methods that are being used to protect it. (8)
2. Using a named example explain how coastal management has had an
impact and the conflict it has caused. (8)
Why does it need
protecting?
What methods are
used?
How has it had an
impact?
What conflicts have
occurred?
-
Sheringham – Hold the
Line – Rip Rap, Sea
Wall, Gabions,
Groynes.
West Runton –
Managed Retreat – old
revetments –
monitoring the
situation
Weybourne – No
defences.
Sheringham has kept
the tourist industry
and protected homes
Environmentalists v.
local people
-
-
Fastest erosion
rates in Europe
because of the
boulder clay cliffs
Rising Sea Levels
Economic value
(towns/villages/
tourism)
Agricultural land
Road networks
Businesses v. Planners
At Weybourne they
have rapid retreat
which is destroying
land.
At West Runton the
village is in increasing
danger
Local home owners v.
tourists
MARINE EROSION
SUB-AERIAL
PROCESSES
ABRASION
The wearing away of rocks by Processes active on the face
and top of the cliffs
the action of the sea.
Waves pick up large
quantities of sands and
pebbles and hurl them at the
face of the cliff.
HYDRAULIC ACTION
ATTRITION
SOLUTION
Waves directly break against
the base of the cliffs. The
sheer force of the water
breaks fragments off the rock
Sand particles and pebbles
Sea water corrodes the cliffs
are constantly colliding with
and slowly dissolves chalk
each other as they are moved and limestone.
by the waves.
WETTING AND DRYING
MASS MOVEMENT
LONGSHORE DRIFT
Softer rocks such as clay
expands and contracts as
they become wet and dry.
This causes weaknesses that
become susceptible to
erosion
Movement of the cliff
including rock falls, mudslides
and landslides. These often
occur because of a
combination of waves and
sub-aerial processes
The transportation of
material at an angle to
coastline, so material travels
along the coast.