Glaciation Revision for you. Get your revision techniques ready!!!! Here we go……………………

Glacial features 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 Pyramidal peaks are formed when three or more corries cut backwards into the same mountain. arête The Ridge is the ARETE tarn 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 hanging valley 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. Have a look at Glacial Troughs: Hanging Valleys, Misfit steams, Truncated spurs Interlocking spurs are truncated as the glacier cuts straight through the landscape. wide and flat valley floor truncated spurs

Nant Ffrancon Valley, Snowdonia What evidence is there to suggest that this valley has been shaped by ice? Expect labels to include: Steep valley sides Wide, flat valley floor Truncated spurs Misfit stream Labels should be detailed and refer to processes such as abrasion and plucking. 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. Can you remember: 4 Figure grid references? 6 Figure grid references?

Google Maps example. http://maps.google.co.uk/maps?hl=en&lr=&safe=active&q=Cairngorms&um=1&ie=UTF-8&sa=N&tab=wl http://maps.google.co.uk/maps?hl=en&tab=wl

Identifying glacial troughs Map of Snowdonia glacial troughs

Examination question List three pieces of map evidence to show that this area was glaciated. Map evidence: Circular lake with steep backwall (contours close together) – a corrie Dotted black lines suggest scree-like features – evidence of steep slopes and frost shattering – could be present day but steepness influenced by glaciation Tightly-packed contours creating circular hollows – several corrie type features cutting back-to-back to create steep ridges that may be arêtes Opportunity to raise map skills techniques here – on an OS map students could quote grid references, heights and named examples

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. 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. Possible answers for two human uses can come from the following: water supply – fast-flowing meltwater rivers, U-shaped valleys dammed as reservoirs energy supply – HEP from steep hanging valleys pastoral farming – steep hillsides and harsh climate but suitable for grazing animals such as sheep skiing – snow on slopes in winter and glacier skiing may be possible all-year round. tourism – sightseeing, walking, climbing Make sure answers are explained and not just described! Two issues – decline in agriculture and growth of tourism Explain how each issue can be managed – depends on choice made in previous question. Teacher to decide how many marks are allocated and so influence volume of information required in this answer. Expect named examples of schemes for top marks!

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.