Erosional landforms: Headlands
Coast The maximum distance over which waves can travel is known as the…
Fetch One of the erosion processes that involves large waves hurtling beach material at a cliff is called……..
Corrasion The landform created along stretches of less resistant coastlines (i.e. areas made of clay) are known as…….
Bays The name given to waves with a weak swash but strong backwash is……
Destructive The process that involves beach material being dropped is more technically known as….
Deposition What is the name given to the predominant force affecting the coastal landscape of the UK…….
Prevailing Winds The process that carries material up and down the beach is known as…….
Longshore Drift What is the name of the process that carries / returns wave energy back down the beach
Backswash The erosion process that breaks up large boulders into small particles by bumping them against each other is known as…..
Attrition The areas of land left protruding into the sea as they are more resistant to wave erosion are called…..
Headlands The force of waves compressing air into cracks in a cliff is an erosion process called…
Hydraulic Action Coastlines can dissolved by salts and acids in seawater. This is also known as….
Corrosion The narrow contact zone between land and sea is more commonly called the…
Match the keyword with its meaning
Headland landforms
The different properties of rocks means they are more or less resistant to erosion.
This means they will change shape in different ways.
Watch the animation of headland landforms being created. headland animation
Pop-up headlands
Follow the instructions to make a pop-up headland that shows caves, arches, stacks, etc.
http://www.flickr.com/photos/sacherfire/217113480/
1
You need your template. This will represent a chalk
headland.
2
Using a blue crayon - colour the outside horizontal strips- these represent the sea.
3
Using a green crayon- colour the middle
horizontal strip- this represents the top of
the headland- exposed to
weathering.
4 Just above the
horizontal blue lines-
shade a grey line-
make sure it reaches
the top of the wave-
cut notch. This
represents wave
action between high
and low tide.
5
Carefully cut out all the black areas on the template- with the
exception of the wave-cut notch.
Don’t cut off your stump!
6
It should look like this...
7 Using a ruler, carefully fold the horizontal lines.
8Like this...
9 Glue along the two blue horizontal strips-
on the reverse!
10
Position the green strip over the centre fold of your book. Gently glue down the blue horizontal strip- the one with the stump.- Practice your positioning first.
11
Carefully practice
folding the model... are
the folds the right way?
12Finally, glue the final
blue strip down. Practice the positioning
first...
13 Gently close your book...
14
Magic...
1
2
3
4 5
6Add a label alongside your pop-up showing what they are: fault,
wave-cut notch, cave, arch, stack, stump
Complete the sentences
Hydraulic action affects headlands by eroding weak ............ in the rocks.
Firstly, a .............. ..................... is created.This is eroded more over time to become a ...........Hydraulic action, corrosion, abrasion and attrition
work to erode the cave to become an .................Eventually the arch ............... under its own weightThis leaves a ................ standing on its ownOver time, weathering and erosion ................. the
stack and it collapses to form a small ................. .
stump collapses undercutarch
stack faults (cracks) wave-cut notch cave
Cliffs and wave-cut platforms
Cliffs are steep rock faces along the coastline, they form along coastlines with resistant harder rocks such as chalk
Wave-cut platforms are rocky ledges on the beach left behind after a cliff collapses. They become smooth over time with erosion.
CLIFFS AND WAVE-CUT PLATFORMS
So how do cliffs and wave-cut platforms form? The erosion of a cliff is greatest at its base where large
waves break - hydraulic action, abrasion and attrition constantly undercut the foot of the cliff
This forms a dent called a wave-cut notch The cliff face is also affected by abrasion as rock
fragments are hurled against the cliff by the breaking waves.
The undercutting continues and eventually the overhanging cliff becomes so heavy it collapses downwards - this process continues over time and the cliff gradually retreats inland and becomes steeper.
As the cliff retreats, a gently-sloping rocky platform is left at the base, this is known as a wave-cut platform which is exposed at low tide.
Using the keywords below and the diagrams from p6 ‘Tomorrow’s Geography’,
produce a four picture step-by-step storyboard
explaining the processes that produces a wave cut
platform.
High Tide
Low TideWave Cut Notch
Corrasion
Retreat
Wave cut platform
Cliff
Hydraulic Action
Wave cut platforms
Copy the exam question into your books, then answer it:
“With reference to erosion processes, explain how wave-cut platforms are formed” {4marks}
How does geology influence landforms?
The different properties of rocks means they are more or less resistant to erosion.
This means they will change shape in different ways.
Watch the animation of a headland being formed. animation.html
Jurassic Coast: Swanage Bay
Differing rock hardness is picked out and exaggerated by wave action.
The hard rocks form headlands and the softer rocks form bays.
Currents are weaker in the bays so beach sediments are deposited.
What can you tell from the map?
The map above shows the stretch of coastline to the west of Lulworth Cove. The features along this stretch provide excellent examples of landforms forming on destructive coastlines. What features can you identify?
What can you tell from the map?
What feature is
this? .......................
What feature is
this? ...........................
What feature is
this? ...........................
YOUR CASE STUDY: Erosion landform
Old Harry Rocks
The Old Harry Rocks are two chalk stacks located at on the Dorset coast in England
About 4 km NE of SwanageThe rocks are part of the Jurassic CoastThe cliff is chalk, with some bands of flint, which
have been gradually eroded over the centuries, Some of the earlier stacks have fallen away (Old Harry's original wife fell in 1896), while new ones have been formed.
Old Harry and his Wife
Old Harry Rocks
Watch the animation
Old Harry Rocks story cards
Read the information cards you have been given
Cut them up, and stick them in to your books in an order that tells the story of what created Old Harry and his wife.
Order:1)Introduction to Old Harry Rocks (background
info, location)2)What created Old Harry, step-by-step
The headland is to the north of Swanage Bay.
Hydraulic action and abrasion takes place.
The area is known as the Isle of Purbeck. It is on the Jurassic Coast.
Chalk is a more resistant rock than clay.
The wave-cut notch undercuts the cliff above, making it unstable.
The stack is still eroded and will eventually collapse and become a stump.
A column of rock is left standing on its own. This is a stack.
Most of this area is clay.
Most wave erosion happens at the base of the cliff.
Wave erosion takes place between the high tide mark and low tide mark.
The arch eventually collapses under it’s own weight.
A wave-cut notch is eroded along the cliff base between high and low tides.
Because the headland juts out in to the sea, it takes the full force of wave erosion.
When chalk is formed, it contains joints which means it has areas of weakness.
Wave erosion picks out the areas of weakness in the chalk cliffs and splits rocks apart in to cracks.
Caves develop on both sides of the headland.
Old Harry already lost one ‘wife’ in 1896 when she collapsed.
Small cracks are formed. Small caves are formed. Wave erosion enlarges the caves.
Old Harry Rocks are in Dorset.
Several lines of weakness go right through the headland cliff, wave action can erode these.
Caves are eroded so far back in to the headland that they meet in the middle and a hole is created that goes through. This creates an arch.
Further erosion causes the arch to enlarge and become unstable.
The headland is made of chalk.
Chalk does not crumble away as easily as clay.
This stack is called ‘Old Harry’.
Caves, arches and stacks cannot be formed in clay.
Old Harry’s wife is a stump. She was created when a stack collapsed a long time ago.
Homework reminder
Extended homework sheet
This does not mean leave it to the last minuteEach week I want an update on what you
have found out so far.This should be a detailed projectDue:
See www.priorygcse.wordpress.com for help
Keyword bingo
Match up the keyword with my description5 in a rowYou must also be able to explain the keyword
in your own words to win