D3r

• Geological hazards


  • They can cause injury, disability, loss of home, loss of income, and even loss of loved ones for some communities
• Reducing and eliminating losses from geological hazards

  1. Taking precautionary measures

  2. Learning about preparedness and immediate response

  3. Imbibing a culture of safety
• rock, dirt or debris falling down a sloping section

  rock, dirt or debris falling down a sloping section of

  
• Causes of landslides


  • Storms
  • Earthquakes
  • Volcanoes
  • Other factors which makes the slope unstable

  
• Major causes of landslides

  • Geology - weakened or stiffened soil or rock layers
  • Morphology - weakened soil or rock structure through loss of vegetation or root system, prolonged rainfall or heavy water leakage
  • Human activity - deforestation, irrigation, construction

  
• Rainfall-induced landslide


  Landslide caused by prolonged or heavy rainfall, increasing the weight of the land mass

  
• Impending signs of a rainfall-induced landslide

  • Unusual noises, such as breaking trees, or knocking boulders together
  • Slight rumbling sound that rises in amplitude as the landslide nears
  • Rapid rise in water levels of the creeks, likely followed by increased turbidity (soil content)

  
• Early Warning System (EWS)


  Monitoring systems designed to forecast events accompanying landslides in order to provide a warning about hazards

  
• Sinkhole


  Depression or hole caused by the collapse of the surface layer of the ground
• Causes of sinkholes


  • Water dissolving soluble rocks such as limestone, dolomite, and gypsum
  • Natural causes - physical or chemical erosion
  • Man-made causes - drilling, mining, road construction, broken water or underground pipes
• Types of sinkholes


  • Solution sinkholes - caused by erosion of bedrock with thin soil cover
  • Cover subsidence sinkholes - caused by erosion of bedrock covered by poorly-knitted soil
  • Cover collapse sinkholes - caused by sudden collapse of deep soil layers over eroded bedrock
• Impending signs of a sinkhole

  • New cracks at the foundations of buildings and houses
  • Cracks in an area
  • Depressions at ground level
  • Rapid appearance of a crater in the ground