Ribbon Lake Arete
Lake Windermere, Lake District Striding Edge, Lake District
1
3
2
Pyramidal Peak Corrie & Tarn
Matterhorn, Switzerland Red Tarn, Lake District
They are all features of glacial erosion
4
KEY IDEAS & QUESTIONS
•To identify and describe landforms created by glacial erosion
•To explain how a landform of glacial erosion is formed – a
corrie and tarn.
3/4 Identify and describe a corrie, tarn, arete and pyramidal peak
5/6 Identify and describe most of the following features; corrie, tarn,
arete, pyramidal peak, truncated spur, hanging valley, U-shaped valley,
ribbon lake and misfit stream. Give a basic explanation of how a corrie
and tarn are formed.
7+ Identify and describe all of the following features with accuracy and
detail; corrie, tarn, arete, pyramidal peak, truncated spur, hanging valley,
U-shaped valley, ribbon lake and misfit stream. Give a clear explanation
of how a corrie and tarn are formed, using key terminology including
freeze-thaw, plucking and abrasion.
We are studying a topic about glaciers. These 3 photos are of
glaciated landscapes. What’s the problem?
There’s no ice!
Glaciated landscapes in the UK were shaped about 20,000
years ago in the last Ice Age.
When the ice melted a new landscape was revealed.
Before glaciation
During glaciation
After glaciation
The study of glaciation is all about imagining what the ice was
doing when there were glaciers here 20,000 years ago.
Match the correct labels to the diagram
Pyramidal peak
Corrie
Arete
Ribbon Lake
Tarn
A tarn is a circular lake formed at the bottom of a
corrie when a glacier melts
A ribbon lake is a long, narrow body of water
A pyramidal peak is a pointed mountain peak with at
least 3 sides
A corrie is an armchair-shaped hollow, high on a
mountain, with steep back and side walls
An arête is sharp mountain ridge
Pyramidal peak
Corrie
Arete
Ribbon Lake
Tarn
Truncated spur
Tarn
Pyramidal peak
Hanging valley
Corrie
Arete
Ribbon Lake
Misfit stream
U-shaped valley
Ribbon lakes are long, thin lakes that
form after a glacier retreats. They form
in hollows where softer rock was eroded
more than the surrounding hard rock.
U-shaped valleys (also called glacial
troughs) are steep sided valleys with flat
bottoms. They start off as a V-shaped
When the ice melts in a corrie it leaves a
river valley, but change to a U-shape as
small circular lake called a tarn.
the glacier erodes the sides and bottom
making it wider and deeper.
Hanging valleys are valleys formed by
smaller glaciers (called tributary glaciers
that flow into the main glacier. The Ushaped valley is eroded much more deeply
by the larger glacier, so when the glaciers
melt the tributary valleys are left at a
much higher level.
A pyramidal peak is a pointed mountain
peak with at least three sides. It is
formed when three or more back to back
glaciers erode a mountain.
Corries begin as hollows
containing a small glacier. As
the ice moves it erodes the
hollow into a steep armchair
shape with a lip at the bottom
end.
Truncated spurs are cliff-like
edges on the valley side formed
when ridges of land (spurs)
that stick out into the main
valley are cut off as the glacier
moves past.
An arête is a narrow steep
sided ridge formed when two
glaciers erode in parallel
valleys. The glaciers erode the
sides of the valleys, which
sharpens the ridge between
them, giving it a jagged profile.
Misfit rivers meander through
the wide U-shaped valley floor.
They look out of place as they
did not erode the valley as they
are so small. They formed
after the glacier melted.
Truncated spur
Tarn
Pyramidal peak
Hanging valley
Corrie
Arete
Ribbon Lake
Misfit stream
U-shaped valley
Match the pictures 1-5 to the correct OS map A to E
1
C
Hanging
Valley
Truncated
spur
B
Truncated
spur
2
3
Misfit
stream
Ribbon
lake
E
4
A
5
D
U-shaped
valley
Focus on corries and tarns
1. Put the cards in the correct order to explain the formation of a corrie and tarn
2. Where do you think each piece of information would be labelled on this diagram?
Freeze-thaw weathering above
Snow collects in a shallow
the glacier breaks off pieces
hollow, turns into ice and then
of rock which fall onto the
moves downhill.
glacier.
Plucking behind the glacier
steepens the back wall.
Abrasion under the ice
deepens the hollow.
A rock lip forms where there
is less erosion. It may be
covered with moraine
deposited by the glacier.
When the ice melts, a bowl
shape is left in which a tarn
may form.
Freeze-thaw weathering
above the glacier breaks
off pieces of rock which
fall onto the glacier.
Snow collects in a shallow
hollow, turns into ice and
then moves downhill.
Plucking behind the
glacier steepens the
back wall.
When the ice melts, a
bowl shape is left in
which a tarn may form.
Abrasion under the ice
deepens the hollow.
A rock lip forms where
there is less erosion. It
may be covered with
moraine deposited by
the glacier.
Stick the labels onto the correct place on the diagram provided.
Make a copy of the diagram in your book and stick the labels onto the
correct place on the diagram.
Make a copy of the diagram in your book and use the card sort to help
you add labels to explain the formation of a corrie and tarn.
KEY IDEAS & QUESTIONS
•To identify and describe landforms created by glacial erosion
•To explain how a landform of glacial erosion is formed – a
corrie and tarn.
3/4 Identify and describe a corrie, tarn, arete and pyramidal peak
5/6 Identify and describe most of the following features; corrie, tarn,
arete, pyramidal peak, truncated spur, hanging valley, U-shaped valley,
ribbon lake and misfit stream. Give a basic explanation of how a corrie
and tarn are formed.
7+ Identify and describe all of the following features with accuracy and
detail; corrie, tarn, arete, pyramidal peak, truncated spur, hanging valley,
U-shaped valley, ribbon lake and misfit stream. Give a clear explanation
of how a corrie and tarn are formed, using key terminology including
freeze-thaw, plucking and abrasion.
Something beginning with…
Plenary
T
Tarn
C
Corrie
P
Pyramidal Peak
A
Arete
T20
Independent
Independent
Learning
Opportunity
T20
Flexible
1. Watch: Everest (2015). How many features of glaciation from
today’s lesson can you spot? Write down a list. What did you
think of the film?
2. Research: Snowdonia in North Wales is a well-known upland
glaciated area. Go online and research into the area.
3. Explore: Either Snowdonia or The Lake District. Make a photojournal or tweet your glacial pics to @WorldAffairsHT
2 can be done as a PowerPoint, on paper, a poster or fact file
Bring your work in to gain an ILO credit 
Have this ready to hand in for: