periglacial processes

Question 1

solifluction

Answer 1

occur in areas of permifrost as the ground starts to thaw
- the layer of permifrost is impermeable
- if the tempreture rises, the active layer melts away but the meltwater cannot drain away
- theu active layer becomes waterlogged and heaver and flows reletavly easily. this can occur whereever there is a gradient

Question 2

solufluction produces …

Answer 2

lobe formations
- this is where one section of soil moves faster than the soil around it often because it is on steeper ground
- the faster flowing section forms a tongue shape

Question 3

freeze thaw weathering

Answer 3

• water settles in the cracks of rocks.
• the volume of water expands by 9% when it freezes
• the ice thaws when the temp rises
• this continual cycle of freezing and thawing will weaken and shatter the rock causing it to shatter ( frost shattering)

Question 4

frost heave

Answer 4

when the ground thaws, the soil particals moce vertically downwards, meaning end up further down the slope.

Question 5

nivation

Answer 5

nivation makes holloes in a sloped landscape deeber by freezing and thawing.
* when snow collects in a hollow, freeze thaw weathering can cause erosion
* frost-shattering breaks bits off the rock at the base of the hollow
* when the snow melts, the meltwater carries the broken bits of rock away
* eventually the hollow becomes deeper and wider

Question 6

wind erosion (aeolian)

Answer 6

• strong winds are likely to be in periglacial landscapes due to there being few tall trees to act as windbreaks
• wind erosion can break up loose till and weaken features of rocky landscapes

Question 7

meltwater erosion

Answer 7

happens mostly in the summer when there are greater rates of ablation and meltwater discharge is far higher