Transcript Glaciation Revision for you.

Glaciation Revision for you.
Get your revision techniques ready!!!!
Here we go……………………
Glacial features
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Corries
Aretes
Pyramidical peaks
Glaciated Troughs (U shaped Valleys)
Truncated spurs
Hanging Valleys
Ribbon Lakes
Morraine
Glacial processes include frost shattering, plucking
and abrasion.
• Frost Shattering is a type of WEATHERING.
• Abrasion and plucking is a type of EROSION.
How is a corrie formed?
Snow collects in a natural hollow on the side of a mountain.
Over time, further snow collects in the hollow. This extra
weight compresses the snow underneath, turning it into ice.
rock lip
The hollow is deepened and
widened by the corrie glacier
through the processes of
abrasion and plucking.
This overdeepening leads
to an ‘armchair’ shape
characteristic of a corrie
and causes a ‘rock lip’ to
be formed.
Corrie formation
Diagram of a corrie
Remember a Tarn is a lake that fills the Corrie
once the Ice has Melted.
Steep Back wall
Bowl Shape Corrie
Formation of a pyramidal peak
arête
tarn
The Ridge is the
ARETE
Pyramidal peaks
are formed when
three or more
corries cut
backwards into the
same mountain.
corrie
Label the pyramidal peak diagram
How and why do these valleys differ?
river valley
glaciated valley
Unlike a river, a glacier fills the entire valley and so
has much more power to erode.
It does not have to wind around interlocking spurs
and can widen, deepen and straighten its valley.
Characteristics of a glacial trough
What are the characteristics of a glacial trough?
steep valley sides
misfit stream
The river
Between truncated
that flows
spurs are hanging
through
valleys which
Have a look at Glacial Troughs:
the valley
have not been
Hanging Valleys,
Misfit steams,
after the
eroded as deeply
Truncated spurs
ice age is
as the main valley.
described
as a
Interlocking spurs are
misfit
truncated as the
stream.
glacier cuts straight
through the landscape.
wide and flat valley floor
hanging valley
truncated spurs
Nant Ffrancon Valley, Snowdonia
What evidence is there to suggest that this valley has
been shaped by ice?
Produce an annotated sketch to show that this is a
glaciated valley.
What is moraine?
Moraine is a type of landform that is created when a glacier
deposits the material (till) that it has been transporting. It is
made up of unsorted angular rocks. There are several types of
moraine:
Lateral
Medial
Ground
Recessional
Terminal
Unsorted, angular rocks make up this moraine
found in the Porsmork Valley, SW Iceland.
How are drumlins formed?
Drumlins are formed of till. They are elongated features that can
reach a kilometre or more in length, 500m or so in width and over
50m in height.
There is still some
debate about how
drumlins are
formed, but the
most widely
accepted idea is
that they were
formed when the
ice became
overloaded with
sediment.
It is common to find several drumlins grouped together.
A collection of drumlins is called a swarm.
Features of glacial deposition
How are ribbon lakes formed?
Identifying Glacial Features on
an OS map.
• First we must know:
– What do contour lines represent?
– What does it mean if they are close
together?
– What does it mean if they are far apart?
Have a look at Glacial Troughs:
Hanging Valleys,
Misfit steams,
Truncated spurs.
Glacial Trough, U shaped
Valley as Contours are
wide in Middle
Identifying Glacial Features on
an OS map.
• Task:
• Collect hand out and match the
pictures on the left to the OS map
boxes on the right.
• Try and imagine looking at them in 3D.
Identifying Glacial Features on
an OS map.
• Can you remember:
– 4 Figure grid references?
– 6 Figure grid references?
Quick test: page 32 of SG Geog
• Write the names at these grid refs
1. 33,12
2. 35,11
3. 35,17
4. 318,106
5. 349,158
Quick test:
• Write the names at these grid refs
1. 33,12
Willie Wife Moore
2. 35,11
FAIRFIELD
3. 35,17
Stang
4. 318,106
Greenburn Bottom
5. 349,158
Catstye Cam
Glacial Features P32
• 347, 152
• 367, 148
• 350, 141
• 349, 120
Glacial Features
• 347, 152
Corrie
• 367, 148
U-shaped valley
• 350, 141
Arete
• 349, 120
Corrie
Glacial Features
• Your turn:
• Try and find another:
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Corrie
Arete
U-shaped valley
Give 6 fig grid refs for them.
Glaciation on an OS map
Re-cap.
• Collect a mini white board and pen
1 between 2 (or 3)
• A number of glacial features will come up
on the board you must draw what they
would look like on an OS map.
Glaciation on an OS map
Re-cap.
Corrie
Arete
U-shaped valley
Pyramidal peak
hanging valley
See Braemar PP
This is the end of the unit.
• Your test date:
• Tuesday 13/09/2011
• LOOK ON THE BLOG,
• everything we have covered is there.
• Is there anything you would like to revise
in class?
Google Maps example.
• http://maps.google.co.uk/maps?hl=en&lr=
&safe=active&q=Cairngorms&um=1&ie=U
TF-8&sa=N&tab=wl
• http://maps.google.co.uk/maps?hl=en&tab
=wl
Identifying glacial troughs
glacial troughs
Map of Snowdonia
Examination question
List three pieces of map
evidence to show that
this area was glaciated.
Glaciation quiz
Key ideas
Corries, arêtes, pyramidal peaks and glacial troughs
are created by glacial erosion.
Moraines, drumlins and erratics are the result of
glacial deposition.
Moraine is a type of landform that is created when a
glacier deposits the material (till) that it has been
transporting.
There are five main types of moraine.
Contour patterns on maps can give a clear
indication as to whether a landscape has been
glaciated.
How do Humans use Glaciated
Areas. USE NAnT Ffrancon Valley
Snowdonia.
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Reservoirs (The Lake District/Snowdonia)
Forestry (The Lake District/Snowdonia)
Ski Resorts (he Alps)
Recreation (The Alps, Lakes, Snowdonia)
Sheep Framing (The Lakes and
Snowdonia)
• Dairy Farming ( The Alps, think of Milka
chocolate, daisy the cow- only done on the lower
slopes and valley floor).
• HEP power stations
Examination question and model answer
Examination question and model answer
Issues affecting Upland Glaciated
areas.
1)A decline in Farming, due to restrictions in
farming involving european policies such as
CAP the common agriculutural Policy, meaning
farmers can only produce so much of a certain
product. Foot and mouth and BSE has put
people off farming.
2) Rapid increase in tourism in places like Lake
District and Snowdonia, huge increase in day
trippers and second home owners= problems
such as demand on environment and erosion.
How can Upland Glaciated areas
be managed.
• Ensuring cheap housing so locals stay in the
area, instead of being out priced due to people
rich city folk buying up property and forcing up
land prices.
• Funding farmers to diversify into other markets,
e.g you saw this at Malham, farmers renting
fields to campers.
• Increasing the council tax on second homes
from 50% to 90%.
• Encouraging tourists and the National Trust to
manage the area SUSTAINABLEY.
Examination question
Study the photograph of a
glaciated landscape:
Explain two human uses
of this landscape.
List two issues that are
affecting upland glaciated
landscapes.
For one of these issues
explain how it can be
managed.
Key ideas
Pastoral farming is traditionally the main land use in upland
glaciated areas such as the Lake District and Snowdonia.
Other land uses include: water supply, energy production,
forestry, transport and tourist facilities including skiing.
The main issues affecting upland glaciated areas are the
decline in farming and the growth of tourism, including
the growth of second home ownership.
The decline in farming and the growth of tourism has created
a range of problems including rural depopulation.
Management schemes exist in order to help upland
glaciated areas adapt to recent changes.