Ice Sheet Scouring Landforms

Question 1

Roches moutonnee

Answer 1

Resistant rock shaped to have a smooth and an angular surface

Increased pressure due to resistance of the rock leads to basal slip which erodes the smooth side of the rock (Faces direction of ice flow)

Reduced pressure causes meltwater to freeze on downstream side so plucking takes place creating angular rock

Question 2

Crag and tail

Answer 2

Ice sheet encounters resistant rock and erodes surrounding softer material, leaving the resistant rock standing out (crag)

The tail is formed when the crag slows ice flow so material is deposited making a slope downstream of the crag

Question 3

Knock and Lochan landscape

Answer 3

Name given to glaciallt scoured landscapes containing alternating knocks (roches moutonnees), which often come with depressions that fill with water to create small lakes (lochan)