To explain how earthquakes are created To discover their impact and how people responded in Japan How close did we come to nuclear meltdown? Key terms: Focus, epicentre, magnitude, Richter scale, nuclear meltdown L

Fukushima Nuclear Power Plant On Friday 11 March 2011 the world came close to its first global nuclear meltdown. Why?

The Cause The cause of this nuclear meltdown was an earthquake. We need to first understand how these form. Earthquakes form when two plates slip past one another at a plate boundary. The plates get caught up due to friction. They suddenly jolt into a new position. This is an earthquake! A plate moves another way A plate moves one way This is where the quake happens. This is where the quake is felt the most. A diagram showing the focus and the epicentre. Copy this!

Sendai: The Epicentre The epicentre lay just of the coast of north east Japan, close to Sendai. Fukushima Power Plant is just to the south. How intense was the shaking here? Draw a sketch map of this. Include the epicentre, the earthquake waves, the power plant at Fukushima. Give it a title and a north arrow.

Sendai: The Epicentre The earthquake measuring 9.0 on the Richter Scale struck off Japan's north-east coast. This is a supermarket in Sendai, close to the epicentre. Japan has more earthquakes than any other country in the world. Yet this was its most powerful ever. It is called a mega-thrust earthquake.

Fukushima Meltdown Explosions and radiation leaks at the Fukushima plant followed the earthquake on 11 March.

Fukushima Meltdown Small groups of workers, known as the Fukushima 50, stayed at the site to try to prevent another explosion and more radiation leaks. The country's Prime Minister, Naoto Kan, praised their dedication and said they were "making their best effort without even thinking twice about the danger". It is likely that the Fukushima 50 will not now live beyond 50. Radiation shortens our lifespan dramatically.

Fukushima Meltdown Radiation is created in a nuclear reactor to make electricity. Usually high-tech safety systems stop it escaping, but these were broken by the earthquake waves.

Fukushima Meltdown Military planes dumped tonnes of sea water on the power plant and water cannons were used on the ground to try to cool it down.

Fukushima Meltdown Radiation damages the cells that make up the human body. High levels can kill you - by causing damage to your internal organs. It's difficult to treat high radiation exposure. Plus, in the long-term, exposure to radiation can cause cancer.

Worst Nuclear Incidents Level 7: Chernobyl, Ukraine, explosion and fallout over thousands of square kilometres, 4,000 new cancer cases Level 7: Fukushima, tsunami and earthquake damage. Long-term effects unknown Level 6: Kyshtym, Russia, explosion in waste tank leading to hundreds of cancer cases. Level 5: Windscale, UK, fire in operating reactor, release of contamination in local area, possible 240 cancer cases Level 5: Three Mile Island, US, instrument fault leading to large-scale meltdown, severe damage to reactor core