japan earthquake + tsunami

• when did the 4th largest earthquake happen?

  March 2011
• how deep was the earthquake's focus?

  20km deep
• earthquake struck 100km off the coast of Sendai
• tsunami occurred
• Japan's tsunami warning system kicked in , people along 3,000km long stretch of coastline had only moments to escape (most live on coast due to mountainous interior of Japan)
• Japan is located at the boundary of 3 plates (Eurasian , Pacific and Phillippine)

  • boundary is to the East of the 4 Japananse Islands : Hokkaido , Honshu , Shikoku and Kyushu
• Japan's plate boundary is...?

  destructive oceanic-continental boundary - Pacific plate subducts 90mm per year under the Eurasian plate with linked faults running directly into Japan
• Japan owes its exsistence to this boundary , islands are volanic in origin
• Japan gets 30% of the world's earthquakes every year
• 32 bridges destroyed
• 15,883 died - 92.5% of these from drowning
• 6,150 injured
• 45,700 buildings destroyed
• Island of Honshu moved 2.4m east and shifted the Earth on its axis by estimates of between 10cm and 25cm
• 2 million left homeless
• recovery cost of $235 billion
• 1.4 million homes without water supply
• aftershocks as large as 7.1 struck , causing tall buildings to sway violently in central Tokyo
• Tokyo's major airports halted flights and all Tokyo area trains were automatically halted including Hinkansen bullet train service
• earthquake caused two nucelar plants on the Pacific coast in Fukushima to automatically shut down - subsequent tsunami disabled emergency generators required to cool the reactors
• evidence of a partial nuclear melton down in units 1,2 and 3 - visible explosions and suspected to be caused by hydrogen gas
• radiation releases due to nuclear power plant breakdown (40,000 times normal dosage) , resulted in large evacuations within 20km radius

  • concerns over contaminated food and water supplies and treatment of nuclear workers
• 340,000 displaced people in region needed catering for and issues included shortage of food and water , shelter and medicine and fuel for survivors
• 91 countries responded to Japan's specific requests for help - UK sent 59 search and rescue experts , four medics and two sniffer dogs who flew out on private charter plane with 11 tonnes of equipment on board
• Japanese Red Cross got $1 billion in foreign aid donations - mobilised 250 emergency teams to the worst affected areas , providing medical and moral support)
• several NGOs sent aid (e.g Shelter Box sent 1,500 boxes of tents , sleeping bags and bottled water within the 1st month)
• long term responses

  • sea walls raised to 7.2m in height
  • city would restore coastal tsunami-control forest 200-400 metres wide and 20-30km long
  • further inland , coastal road would be raised from current 2m to 6m above sea level
  • major population would be found on higher ground further inland
  • charges would reduce inundation by 60%
• exclusion zones and shelters were set up in schools for those who lived in close proximity to the Fukushima Daiiichi nuclear power plant , iodine tablets were provided to prevent radiation sickness