Glacial erosional features

Describe the landforms resulting from *glacial erosion* shown in figure 3 (4marks) Need more than 1 landform for 4 marks Given picture- say what you see about the landforms from glacial erosion List and state about characteristics of each

1) *Corrie* - steep back wall is visible, Corries appear to have snow in them. 2) *Arêtes* appear as narrow ridges, where they meet 3) *Pyramidal peaks* Clear - horn shape; highest points. 4)*Truncated spur*,blunt-ended rock ridges forming steep valley side to glacial trough are visible

Formation of truncated spurs

Ice removes interlocking spurs to create truncated spurs of side and deepens and widens the valley via abrasion, plucking and bulldozing.

Choose one of the landforms of glacial erosion shown in Figure 3. Name the landform and explain its formation. 1) Process of ice formation and intermediate stages where firn/neve is formed.

1) Process of ice formation and intermediate stages where firn/neve is formed. *Neve* *Firn* *Ice* 1) Snow fall onto mountain - lots of *air pockets* 2) Lower layer gets compressed 3) *Firn * more compacted layer of snow-Snow particles closer to each other 4) Snow compact even more 5) melt water seep between snow particles this will eventually freeze and become *Ice*

Choose one of the landforms of glacial erosion shown in Figure 3. Name the landform and explain its formation. 2) Formation of Corries MUST DESCRIBE IN DETAIL *Where Process occur*

Processes 1) *Freeze-thaw weathering* on the *back wall* results in *loose material* fall onto glacier (Freeze-Thaw weathering= Water enters cracks in rocks and when temperature drops below 0C the water in the crack *freezes* and *expands*, Overtime *repeated* freeze thaw action weakens the rocks and cause rocks to *fall off*) 2) *Plucking* from *back, sides* and *base* also creates *loose material within corrie* glacier. (Plucking occurs- As ice and glaciers move, they scrape along the surrounding rock and pull away pieces of rock which causes erosion) 3)*This moraine* is used in *Abrasion*. (Abrasion= Rock fragments carried by the glacier scrape the rock below. The ice flow in the valley leaving striations in the bedrock) 4) The *Rotational Slip Movement* creates the *Armchair shape* of the Corrie forming a tarn after glaciation 4)Corries form best on *north east/east facing slopes* in *northern hemisphere* due to aspect