- Created by: DoRevision123
- Created on: 20-05-18 15:26
Japan - Tectonic Setting.
- Located in one of most tectionally active areas on plate boundaries in world.
- Four tectonic plates meet, widespread seduction leads to intense volcanic activity.
- nearly 12000 volcanic eruptions recorded in past 2 millenia.
- Different scales of average frequency for volcanic eruptions suggest less variable frequencys equate to more explosive ones.
Great East Japan Earthquake: Tohoku.
- One in five top recordings in Japanese history.
- 11 March 2011.
- 9Mw in magitude.
- Epicentre 70km East of Oshika Peninsula.
- Focus was 30km.
- 400km of coastline dropped by 0.4km.
- Lasted six minutes.
- Undersea megathrust earthquake.
- Seismic energy are caused by the same force generating volcanoes but instead bring the risks of tsunamis.
- Pacific coast is especially vulnerable as it has a dense population and comes with three huge conurbations; Tokyo, Osaka and Nagoya.
- 16,000 deaths, 6000 injuries.
- (2/5) 60+, (1/4) 70+.
- 90% deaths were due to drowning, the rest being from burns and collapsed buildings.
- 100,000 seperated from their families with their whereabouts being an inssue. 2000 had lost at least one parent.
- Traditional mourning regimes had to be abandoned for mass burial of dead bodies as the government agreed this would minimise the spread of disease.
- When one elementary school collasped, 10/13 teachers and 74/108 students were lost.
- 230,000 vehicles were either destroyed or damaged; 15 ports were directly affected, with four destroyed in the northeast of Japan, including Sendai.
- 4.4 million households and thousands of businesses lost electricity. The major cause of this disruption was the immediate shutdown of 11 nuclear reactors.
- At the Fukushima Daiichi nuclear power plant (Figure 14.26), all six of its reactors were so severely damaged by the tsunami that the plant was decommissioned.
- Some 25 million tonnes of debris was created by the earthquake, requiring a costly clean-up operation. Over large areas, farmland flooded by sea water has been contaminated by salt and made uncultivable.
- Transport infrastructure was badly hit. Many road bridges were damaged or destroyed and in the northeast train services were badly disrupted.
Some 25 million tonnes of debris was created by the earthquake, requiring a costly clean-up operation. Over large areas, farmland flooded by sea water has been contaminated by salt and made uncultivable.
- Japanese government injected billions of yen into the economy, especially the financial sector, to bring some stability. This increased government debt at a time when its reduction was a prime political aim.
After the Tohoku earthquake. Concerns over safety standards and regulation of the nuclear industry became a political issue.
The government has yet to make a clear decision about the role of nuclear power in Japan’s long-term energy mix. Several executives of companies involved in the Fukushima power plant have resigned.
emerged that warnings about the inadequacy of the defences against tsunami hazards had been made several years before the disaster.
- Tsunami warning systems off the coast.
- Fire proofing older buidings more suspectible to burning, common in older city districtsof Japan.
- Land-use zoning providing open spaces for assembly after earthquakes.
- Controlling building in locations suspectible to liquefaction or excessive ground shaking.
- Research and monitoring; JMA provides mitigation strageties for tectonic hazards such as extreme weather, tsunamis and earthquakes by providing information and warning about impending disasters.
- Using aseismic design in buildings.
- Japan has vast resources to manage losses caused by earthquakes.
- Well-rehearsed recovery and reconstruction plans, at national, regional and local levels, can be actioned immediately following an earthquake.
- To rebuild physically, economically and socially ASAP.