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NATIONAL GEOGRAPHY
GLACIATION REVISION
Upland Glaciated Landscapes
By the end of this Unit of work you should be able to understand that:
•Glaciers are made of ice and they flow very slowly. •Glaciers erode, transport and deposit material.•Glaciers create lots of different landforms.•Glacial landforms can be recognised on maps.•Glaciated upland landscapes can be used in a variety of ways.•Glaciated upland landscapes need to be managed for the future.•Weather affects glaciated upland areas in certain ways.
Location of Glaciated Landscapes
Freeze thaw Action or Frost shattering
It is most effective where the temperature fluctuates around 0°C, eg on north-facing high altitude slopes.
Freeze thaw action causes the rock to shatter.
Sharp, angular pieces of rock are formed called scree.
The broken rock falls and builds up at the base of an area of exposed rock. To form a scree slope.
Generally the larger material builds up at the base, while finer grains are washed into spaces.
The angle of a scree slope is 25-30 degrees
Plucking
Plucking is when rocks and stones become frozen to the base of the glacier and are plucked from the
ground as the glacier moves.
•Rocks and stones, picked up by the glacier are rubbed against the bedrock at the bottom and sides of the glacier.• The rock is scratched, polished, smoothed and eventually worn away by the scouring action.• The pieces of rock in the ice also become smaller through this rubbing action.
These lines on rocks are called striations Abrasion
Direction ice movement
Bedrock is scratched and polished
Rocks scrape against the bedrock
• Snow collects in hollows and compacts to ice.• Ice moves under gravity and its own weight, lubricated
by meltwater-rotational sliding.• Ice erodes more at the base and back of the hollow to
form a raised lip at the front• Abrasion deepens the corrie.• Plucking and freeze thaw action steepens the back and
sides.• A Corrie lochan (tarn) may fill hollow.
Label it to show:-Overdeepened hollow steep back wall rotational sliding/slip scree moraineplucking abrasion freeze thaw tarn lip
Formation of a Corrie
lip
steep backwall
scree
tarn
plucking
abrasion
Overdeepened hollow
freeze thaw action
Rotational sliding/slip
moraine
When three or more corries erode backwards a sharp pointed pyramid shape is created.
This is called a PyramidalPeak or Horn.
Matterhorn
Formation of a Pyramidal Peak or Horn
• Three or more corries form around a peak.• Where corrie sidewalls meet they form an arête (knife
edge)• The corrie erode into the peak.• Arêtes meet to form a horn (pyramidal peak).
Formation of a Pyramidal Peak or Horn
1. Name the glacial erosion features shown in the diagram.
2. Choose one of the following and with the aid of an annotated diagram explain its formation:
corriecorrie
arêtearête
Pyramidal peakPyramidal peak
tarntarn
a)a)b)b)
c)c)
d)d)
Recap
Characteristics of a Glacial U-Shaped Valley
truncated spurs
hanging valley misfit stream
wide and flat valley floor
steep valley sides
Interlocking spurs are truncated as the glacier cuts straight through the landscape.
Between truncated spurs are hanging valleys which have not been eroded as deeply as the main valley.
The river that flows through the valley after the ice age is described as a misfit stream.
Truncated Spurs
Truncated spurs are rounded areas of land which have been cut off. They are often rounded at the top but steep at the bottom. They are formed when glaciers move through the main valley and cut off spurs.
How and why do these valleys differ?
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.
river valley glaciated valley
Before Glaciation
During Glaciation
AfterGlaciation
V Shaped river valley
Interlocking spurs
Corrie glaciers flow into main valley
Main valley glacier
Smaller tributary valley
Valley overdeepened, widened, straightened
Wide flat bottom,steep sides
Hanging valley clip A hanging valley is a smaller side tributary valley left 'hanging' above the main u-shaped valley. A waterfall can often be seen. During glaciation the smaller side valley contains less ice than the main glacial valley, which is why it is not as deeply eroded.
Misfit rivers meander flow through the flat, wide U-shaped floor. They look too small for the size of the valley. They did not erode the valley, as they formed in the valley after glaciation had carved out the U-shaped valley.
Name the features shown in the diagram below:corrie, pyramidal peak , hanging valley, truncated spur, alluvial fan, tarn, arête, ribbon lake , misfit stream, U shaped
Fieldsketch of Cwm Idwal looking south-west
tarn
steep backwall
fence
shattered rock/scree
Learning Intention To understand what upland Glaciated Erosion Features look like on O.S Maps.
Success Criteria To be able to use a variety of OS Maps to identify upland glaciated features.
Corrie and Corrie Loch on a Map
Notice the circular contour lines to represent the circular shape of the corrie. They are close together to show the steepness of the back and side walls. The corrie loch is represented by an area of blue to show water.
Tarns or lochans can be found within the horseshoe shaped corrie
Armchair shaped hollow Look for Horseshoe shaped contours
Names also help such as corrie,cirque,cwm,coire
An arête is found between two corries the land is high and the symbol for bare rock appears
Bare rock
corrie
Corrie with a tarn
Arete on an O.S.Map
Corries
Look for a spot height or a triangulation station with 3 or more corries surrounding it.
Pyramidal Peak on an O.S.Map
U-shaped Valley on a Map
Notice that the lines are very close together at each side to represent the steep sided valley walls and there are no contour lines in the middle because the valley floor is flat.
Whiteness on map due to flat valley floor
Ribbon Lake
Steep Valley sides close contours
U-shaped valley and Ribbon lake on an O.S.Map
Truncated Spurs look for the black rock outcrop pattern running parallel along the sides of the U-Shaped valley
Scree broken rock – look for black dots
U-shaped valley with misfit stream that looks too small for the size of the valley
a
b
c
d
e
f
g
Task 1 identify the features labelled below:
You may see a lot of tourist symbols, why might that be?
Glaciated areas are very attractive to tourists. They provide:
– Beautiful scenery– Recreational (sport) facilities
• Skiing• Hill walking• Rock Climbing• Mountain biking• Watersports
Picnic Site: remember tourist symbols are blue.
List three pieces of map evidence to show that this area was glaciated.
Examination question
Glaciation Map work
•Can you identify a U-shaped valley by giving a grid reference?•Can you identify a Corrie and Corrie loch by giving a grid reference?•Can you identify an arête and pyramidal peak?
Land Use in Loch Lomond clipLearning Intention- To understand how the different glacial features are used.Success Criteria- To explain the advantages and disadvantages of different landuses.
National Parks in the UK A National Park is a large area of countryside protected by rules and laws. National parks are found in beautiful and special areas including mountains, moorlands and coastal areas.
Scottish National Park Aims• to conserve and enhance the natural and
cultural heritage of the area, • to promote sustainable use of the natural
resources of the area, • to promote understanding and enjoyment
(including enjoyment in the form of recreation) of the special qualities of the area by the public, and
• to promote sustainable economic and social development of the area’s communities
Can you spot 8 landuses in this upland glaciated landscape.
Hydro Electric Power
Hanging valley
Loch Sloy
Forestry
Quarrying/Mining
Tourism
Learning Intention -To understand the reasons for large numbers of tourists visiting Loch Lomond.
Success Criteria –To sort impacts of tourism into
benefits and problems.
• THE A82 ROAD AS IT SKIRTS THE EDGE OF LOCH LOMOND
Benefits of Tourism
Problems of Tourism
Land Use Conflicts
Learning Intentions- Understand the pressure on the landscape from a variety of usersTo be able to describe land use conflicts in a National Park.
Conflicts Quarrying vs. Tourists/ Famers/NP-Dust from blasting, lands on farmers fields harming crops-Traffic congestion on local roads due to slow moving trucks- Noise of blasting ruins peaceful atmosphere of National Park and dust and waste can enter rivers- Decline in number of tourists- Blasting is noisy and creates dust and air pollution- It is not sustainable and uses non renewable resources-Animal habitats ruined, breeding grounds disrupted and farm animals frightened.
Solutions- Leisure activities e.g. paint balling or climbing walls
- Quarry signs to show times/days of blasting- Cover trucks before they leave the site
- Hose off trucks to wash off excess dust or transport rock by railway
- Hide disused quarries with trees- Fill quarries with water for fishing/nature reserve
Solutions
- Leisure activities e.g. paint balling or climbing walls- Quarry signs to show times/days of blasting- Cover trucks before they leave the site- Hose off trucks to wash off excess dust or transport rock by railway- Hide disused quarries with trees- Fill quarries with water for fishing/nature reserve
Tourists vs local-Second homes force up house prices meaning some locals can’t afford houses- Jobs are seasonal- Increase in traffic on local roads; pollution and journey times- Tourism raises prices in local shops so villagers can’t afford higher prices-New developments spoil the view e.g caravan sites, hotels
Solutions-Limit number of second homes in area- Tighter regulations for planning permission and new developments- Encourage use of facilities all year round e.g. hotels for conventions, field trips,special offers- Diversification e.g farmers can supplement their income though other activities such as a farm shop, quad biking- Park and ride facilities from major cities
Tourists vs Farmers/N.P- Tourists drop litter which animals can choke on- Tourists leave gates open causing animals to escape- Litter causes visual pollution- Footpath erosion caused by tourists not sticking to the path- Noise and congestion problems
Solutions-National park rangers educate tourists about the Park and can issue on the spot fines- More signs to encourage people to take litter home- Swing shut gates- Stone lined paths or fences put up
Role of Organisations that protect Loch LomondLearning Intention : To understand the role of different organisations which help to protect upland glaciated areas.Success Criteria;To recall different management strategies used to help protect upland glaciated areas.
RSPB- Inversnaid RSPB nature reserve has been set up to increase the amount of native woodland for the benefit of breeding birds, such as pied flycatchers and wood warblers.
The Great Trossachs Forest project is a collaboration made up of Forestry Commission Scotland (FCS), RSPB Scotland, Woodland Trust Scotland (WTS) and multi-national company, BP.
The main aims of The Great Trossachs Forest project is for sustainable land management and use. Tree planting, natural woodland regeneration to try and increase the wildlife.
Scottish Natural Heritage is the government's adviser on all aspects of nature and landscape across Scotland. They aim to help everyone understand, value and enjoy Scotland's nature now and in the future The John Muir Trust is a UK conservation charity dedicated to protecting wild places. It also runs an environmental award scheme encouraging awareness and responsibility for the natural environment, in a spirit of fun, adventure and exploration.
SEPA manages the water environment(quality,pollution levels). Examples of work:Managing recreation on and around water bodies through Byelaws on Loch Lomond and codes of conduct (speed restrictions, laws on boats/behaviour)Education Working with communities/partners to protect and enhance the water environment.Work with user groups fishermen, commercial boat users, tourists.
