Periglacial processes - Mass movement

Question 1

Give three mass movement periglacial processes?

Answer 1

• Frost creep
• Solifluction / gelifluction
• Rockfalls

Question 2

Describe the process of frost creep?

Answer 2

The net downward displacement which occurs when rock and soil particles expand at 90 degrees to the surface during freezing and fall down to the ground vertically on thawing.

Question 3

Which features are associated with frost creep?

Answer 3

Unstratified ‘drift’ deposits on lower parts of valley side slopes.

Question 4

Describe the process of solifluction?

Answer 4

The slow, downslope movement water-saturated soil. As this definition is not confined to cold climates, the more specific term gelifluction is used to describe solifluction associated with frozen ground.

Question 5

Give some features associated with solifluction / gelifluction?

Answer 5

• Solifluction lobes
• Terraces
• Head deposits

Question 6

Describe the process of rockfalls?

Answer 6

The free fall of rock detached by freeze-thaw weathering to the base of the base of a steep slope.

Question 7

Give some features associated with rockfalls?

Answer 7

• Scree
• Pro-talus rampart