Mass movements

• Mass movement

  
• Mass movement means the movement of any loose materials (rock,soil,mud) down slopes under the influence of gravity.
• Factors that affect mass movement.

  • gradient is the slope-faster movement for steeper slopes.
  • water after heavy rain the regolith gets heavy causing the slope to move down faster.
  • human activity- cutting hillsides to make roads and railway lines steeper slopes cause mass movement.
  • vegetation - the roots of trees and plants keep the regolith together this slows down mass movement
• Mudflows are rivers of rock, soil and water. heavy rain and land must be sloped. Land becomes saturated and can’t hold rain, it then slides down slope.
• Bob bursts occur after heavy rainfall the rainwater causes the peat to become saturated
• Landslide rapid movement of regolith(loose material) down a very steep slope this can be caused by quarrying,roadbuilding and earthquakes
• Soil creep

  • Soil moving down a gentle slope under the influence of gravity.
  • it is the slowest type of mass movement and it is difficult to see
  • The evidence of it is tilted trees.
  • Series of steps which are called terracettes

  
• i) The landslide may have been caused by large amounts of loose rocks and soil suddenly sliding down a steep slope. This happens when slopes become unstable and are most common in upland and coastal areas. Most landslides occur when slopes are undercut by sea erosion or human activity such as road building.