Exam-style Questions: Glaciers

 

 

  1. a) Describe two processes of erosion that occur in glaciated areas.

    (4 Marks)

    b) Describe what happens during the process of freeze-thaw weathering.

    (3 Marks)

    c) What is the meaning of the term ablation?

    (2 Marks)

    d) What is the meaning of the term accumulation?

    (2 Marks)

    e)What is the meaning of the term snout?

    (1 Mark)

    (Marks available: 12)

    Answer

     

    Answer outline and marking scheme for question: 1

    a) Give yourself 1 - 2 marks for mentioning any of the points below:

    • Abrasion: Glaciers carry large amounts of material in them/these scrape along the valley floor like sandpaper.
    • Plucking: Ice freezes to large boulders and rips them out of the ground.

     

    Give yourself 3 - 4 marks if you expanded any of the above points, writing in more depth.

    • Abrasion causes the valley floor to be polished and creates grooves called striations.
    • Plucking is the main erosive process/ice melts slightly and then refreezes on boulders. It often occurs on the back wall of corries/these rocks often become the erosive agents of abrasion.

     

    (4 marks)

    b) Give yourself marks for mentioning any of the points below:

    • Water enters cracks in the rock during the day/overnight the temperature drops and the water freezes
    • As it freezes it expands and the expanded ice places pressure on the rocks around it.
    • Over time this constant pressure on the rock causes it to crack and split.

     

    (3 marks)

    c) Give yourself marks for mentioning any of the points below:

    • Ablation is the melting of ice/mainly during the summer months/it usually occurs at the end (snout) of the glaciers.

     

    (2 marks)

    d) Give yourself marks for mentioning any of the points below:

    • Accumulation is the build up of glacier ice/due to snow being compacted into ice.

     

    (2 marks)

    e) The snout is the end of a glacier.

    (1 mark)

    (Marks available: 12)

  2. Exam Style Questions

     

    The diagram shows a sketch of a corrie or cirque after glaciations.

    a) Label features A, B and C.

    (3 Marks)

    b) What process of erosion is most likely to have occurred at D?

    (1 Mark)

    c) Describe how arêtes are formed.

    (3 Marks)

    d) What are hanging valleys?

    (1 Mark)

    e) Describe how are hanging valleys are formed

    (3 Marks)

    (Marks available: 11)

    Answer

     

    Answer outline and marking scheme for question: 2

    a) A = Pyramidal peak.

    B = Tarn or corrie lake.

    C = Rock lip or corrie lip.

    (3 Marks)

    b) D = Plucking (freeze-thaw may also be accepted - although it is a process of weathering).

    (1 Mark)

    c) Give yourself marks for mentioning any of the points below:

    • Arêtes occur where two corries are formed back-to-back.
    • The corries erode backwards by the processes of Abrasion and Plucking (you may want to explain these processs) until they create a narrow knife-like ridge between them.reaks through the neck.
    • An example is Striding Edge In the Lake District. (You may want to include a simple diagram).

     

    Exam Style Questions

     

    (3 marks)

    d) Hanging valleys are tributary valleys that are on the main valley wall high above the main valley floor. They often have waterfalls in them.

    (1 mark)

    e) Give yourself marks for mentioning any of the following points below:

    • Smaller glaciers that flow into the main glacier are called tributary glaciers.
    • They do not have the same erosion power as the main glacier.
    • Because of this they end up being chopped of by the main glacial valley and now hang above the main glacier floor.

     

    (3 marks)

    (Marks available: 11)

  3. a) Describe the features of ground moraine (also known as boulder clay).

    (3 Marks)

    b) What are drumlins?

    (2 Marks)

    c) What are erratics?

    (2 marks)

    d) Look at the diagram below. It is a cross-section of an upland and lowland glaciated area. Name the features A, B and C. Choose your answer from the following list:

    Terminal moraine, ribbon lake, arête, corrie, recessional moraine, pyramidal peak, truncated spur.

    Exam Style Questions

     

    (3 marks)

    e) How are U-shaped valleys formed?

    (2 marks)

    (Marks available: 12)

    Answer

     

    Answer outline and marking scheme for question: 3

    a) Give yourself marks for mentioning any of the following points:

    • Mixed angular material.
    • Found on valley floors.
    • Deposited by glaciers as they melt.
    • Made up of unsorted sand, stones and clays.
    • The stones are angular, as they have not been rounded by water action.

     

    (3 marks)

    b) Give yourself marks for mentioning any of the points below:

    • Drumlins are smooth mounds of deposited material.
    • They are formed parallel to the direction of movement of the glacier.
    • They are quite large - 30-40m high and 500m long.
    • They look similar to an egg.

     

    (2 marks)

    c) Give yourself marks for mentioning any of the points below:

    • Erratics are boulders carried by the glacier and then deposited in an area of differing rock type.
    • They can originate from hundreds of miles away.

     

    (2 marks)

    d) A = Ribbon Lake.

    B = Recessional moraine.

    C = Terminal moraine.

    (3 marks)

    d) Give yourself marks for mentioning any of the following points:

    • Ice fills the whole valley.
    • Erosion takes place on both sides and the valley floor.
    • The valley becomes straighter as the ice does not wind around spurs or areas of hard rock - it cuts straight through them. The glacier has much more power than the river it replaced - thus it erodes the slope material, deepening and widening the valley into a U shape.

     

    (2 marks)

    (Marks available: 12 marks)