Earthquakes

• Features of earthquakes: (definitions)

  Earthquake - sudden movement of the earth’s crust

  Fault - a crack in the earth’s surface

  Focus - the place in the earth’s crust where the earthquake begins

  Tremor - a severe shock of movement as an earthquake occurs

  Aftershock - smaller tremors that happen in the hours or days after an earthquake

  Seismic Waves - a wave of energy that travels through the crust.
• Types of effects an earthquake causes:

  Primary effects - occurs as a direct result of the ground shaking e.g buildings collapsing & landslides

  Secondary effects - happens due to the primary effects - tsunamis, wilders due to gas pipe bursts.
• Ways to predict earthquakes:

  • Seismometers
  • Changes in groundwater
  • Behavior of animals
  • Nowcasting
  • Studying existing geological evidence
• Liquefaction

  1. A phenomenon in which the strength & stiffness of soil is reduced by earthquakes shaking.
  2. Over-Saturation, cannot sustain buildings —> collapse of buildings.
• Long term Impacts — Social

  • Communities are disrupted
  • Relocation—refugees
  • Diseases…
• Long term Impacts - Economic

  • Destroyed buildings - costly to repair/reconstruct
  • Investments only focus on damaged areas; income lost
  • e.g Japan 2011 magnitude 9.0 earthquake —> international debt due to reaching out for global assistance (navy ships etc.)
• Long term impacts - Environmental

  • Landmarks destroyed —> human & natural monuments with historic significance
  • Forests wiped off the face of the earth
• Short term effects of earthquakes - Social


  • Water piped bursting
  • Casualties
  • Transport links affected
• Short term effects of earthquakes - Economic impacts 


  -Industries closed

  -Theft and robbery

  -basic trade difficult
• Short term effects of earthquakes - Environmental impacts

  -Affected area

  -Wildfires due to pipe explosions

  -Tsunamis -flash floods