Landforms of glacial erosion - Roches moutonnees

Question 1

What are roches moutonnees?

Answer 1

Roches moutonnees are asymmetric projections of rock that vary in height from 1m to 50m or more with a smooth stoss side and a steeper, rougher lee side.

Question 2

What is the smooth side of a roche moutonnees called?

Answer 2

The stoss side

Question 3

What is the rough side of a roche moutonnees called?

Answer 3

The lee side

Question 4

When do roche moutonnees form?

Answer 4

They develop when ice is forced to flow and deform around an obstruction.

Question 5

What do roches moutonnees provide evidence of?

Answer 5

They provide evidence of the direction of ice flow and may have been shaped during multiple phases of glaciation.

Question 6

When ice crosses a resistant rock outcrop, increased pressure results in what?

Answer 6

The ice reaching its pressure melting point which induces basal sliding.

Question 7

When the ice reaches its pressure melting point, basal debris is brought into contact with the rock which is smoothed by which process?

Answer 7

Abrasion

Question 8

During the formation of roches moutonnees, there is a reduction of pressure on which side?

Answer 8

The lee side

Question 9

During the formation of roches moutonnees, a reduction in pressure on the lee side causes what?

Answer 9

Regelation

Question 10

During the formation of roche moutennees, regelation takes place, what is the impact of this?

Answer 10

Ice freezes to the down-valley side and pulls chunks of rock away when the glacier moves, producing a steep, jagged slope.