2011 japan earthquake (Tohoku)

• earthquakes are very difficult to predict as they can happen at any place along a tectonic plate boundary.
• indicators of earthquakes:

  • raising levels of radon (radon monitor)
  • changes to the electromagnetic field
  • animals start behaving weirdly
  • seismometers are able to pick up P waves immediately after a quake as they travel the fastest.
• planning for an earthquake:

  • regular earthquake drills in schools.
  • earthquake detection systems that send out warnings when an earthquake is detected.
  • tsunami warning centre in Hawaii.
  • coast towns built sea walls 10 metres high.
• earthquake proof buildings

  most modern business buildings have a design called seishin. seishin dampers that absorb the shook of the earthquake (they act like springs)
• earthquake proof buildings 


  a swinging weight can counteract the movement of the ground (keeping the building upright)
• earthquake proof buildings 


  buildings can be built on rubber legs which sway back and forth when the ground moves.
• impacts on people:

  • 19,000 people died.
  • 500,000 people were made homeless.
  • high levels of radiation increased the risk of cancer in the local residents by about 1%.
• impacts on the environment:

  • 2000 km of the coastline was devastated by the earthquake and tsunami.
  • as the tsunami swept 10 km inland, it demolished everything in its path.
  • the east coast of japan dropped by one metre.