Geomorphological erosional landscapes and landforms

Question 1

How do corries form?

Answer 1

• When snow continues to build in a depression or nivation hollow eventually turn into a glacier.
• Glacier is trapped in the hollow, can only move with rotational slip.
• Back wall eroded through plucking frost shattering.
• When the glacier is gone water can fill corries, making tarns.

Question 2

How do arretes form?

Answer 2

• A knife-edged ridge formed between two corries.

- If three meet they can create a pyramidal peak.

Question 3

How do glacial troughs form?

Answer 3

• U-shaped valleys are formed by glaciers bulldozing though V-shaped valley.
• Leaves small but smooth truncated spurs on valley side and a wide, flat valley floor.
• River that originally flowed will remain - named misfit stream due to its small size compared to surrounding.

Question 4

How do hanging valleys form?

Answer 4

• Form next to a U-shaped valley from a tributary glacier.
• Small glacier does not have the energy to erode the valley floor.
• waterfalls often form there.

Question 5

What are roches mountonnees?

Answer 5

• A mound of rock shaped by a glacier moving from the stoss side to the lee side.
• The glacier hits an obstacle too big to pluck so moves over it.
• Abrasion happens on the stoss side with plucking happening on the lee side.