DRRR landslides

• Landslides


  The movement of a mass of rock, debris, or earth down a slope
• Sinkholes


  A depression or hole in the ground caused by some form of collapse of the surface layer
• Landslides


  • A type of "mass wasting," which denotes any down-slope movement of soil and rock under the direct influence of gravity
  • Encompasses five modes of slope movement: falls, topples, slides, spreads, and flows
• Signs of impending landslides

  • Bulging Ground appearing at the base toe of a slope
  • Water breaks through the ground surface in new location
  • Fences, retaining walls, utility posts or trees tilt or move
  • Cracks appear on slope
  • Water pipes break
  • Cracks appear on the foundation of buildings
  • Doors and Window jammed
  • Water appear on base of the slope
  • Cracks in ground or paveways
  • Outside walls being pulled away
• Erosion


  The geological process in which earthen materials are worn away and transported by natural forces such as wind or water
• Weathering


  Breaks down or dissolves rock, but does not involve movement
• Types of sinkholes

  • Cover Collapse
  • Cover Subsidence
  • Dissolution
  • Artificial
• Debris Avalanche


  Large scale, extremely rapid downslope movement of fragmented debris from the collapse of an unstable slope
• Debris Avalanche


  • Can be volcanic or non-volcanic in origin
• Debris Flow


  Rapid downslope movement of a mixture of water and debris consisting of less than 50% fine-grained material
• Mud Flow


  Rapid downslope movement of a mixture of water and debris consisting of greater than 50% fine-grained material
• Translational Slide


  Downward movement of mass with little to no rotational movement along a relatively planar surface, such as faults, joints, and bedding surfaces
• Rotational Slide


  Downward and outward movement of mass along a curved surface. Occurs most frequently in homogenous material
• Topple


  Forward rotation and movement of a mass of rock or debris out of a slope around a point below its center of gravity
• Rock Fall


  Abrupt detachment of rock from a steep or vertical slope. Size varies from individual rocks to massive boulders
• Creep


  Very slow and steady downslope movement of soil and loose earth material
• Spread


  Extension of cohesive soil or mass of rock due to an underlying softer, weaker layer. Generally occurs on very gentle slopes