Zusammenfassung der Ressource
Mass Movement
- Movement of regolith (rocks, mud, soil) downslope
- Factors Influencing Mass Movement
- Gradient
- Steeper = faster + more likely
- Water
- Heavy rain = heavier regolith + lubricant
- Vegetation
- Roots slow down mass movement
- Human Activity
- Interfering with slopes (undercut) = steeper + more likely
- Types of Mass Movement
- Grouped according to speed + moisture
- Soil Creep (Slow + Dry)
- Slowest type (<1cm per yr)
- Tilted poles, bent trees, broken fences, collapsed walls, terracettes, etc.
- Landslides (Fast + Dry)
- Material slides down an unstable slope
- Heavy rainfall
- Upland + coastal (+ undercut) areas
- Sierra Leone (2017)
- Very destructive
- Mudflows (Fast + Wet)
- Fastest type (several km)
- Rock, earth, silt, peat, etc.
- Bogburst
- Peat + heavy rain = slurry
- Very destructive + pollutes
- Destroyed houses, roads, habitats, polluted rivers, etc.
- Derrybrien, Galway (2003)
- Lahar
- Volcanic eruption + snowy mountain region
- Mud, ash , hot water, etc.
- Looks like concrete river
- Nevado del Ruiz, Andes + Armero (1985)