Periglacial processes - Mass movement Flashcards
Give three mass movement periglacial processes?
- Frost creep
- Solifluction / gelifluction
- Rockfalls
Describe the process of frost creep?
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.
Which features are associated with frost creep?
Unstratified ‘drift’ deposits on lower parts of valley side slopes.
Describe the process of solifluction?
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.
Give some features associated with solifluction / gelifluction?
- Solifluction lobes
- Terraces
- Head deposits
Describe the process of rockfalls?
The free fall of rock detached by freeze-thaw weathering to the base of the base of a steep slope.
Give some features associated with rockfalls?
- Scree
- Pro-talus rampart