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What is a magnitude 10 earthquake like?

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Otherwise known as quakes or tremors, it is estimated that Earth is subjected to around 500,000 earthquakes each year.

Asked by: Richard O’Neill, Glasgow


The 2011 Tōhoku earthquake off the coast of Japan created a tidal wave 40m high and shifted the entire main island of Honshu east by 2.4m. More than 127,000 buildings collapsed and almost 16,000 people died. This magnitude 9.1 earthquake only released about 3 per cent of the energy of a theoretical magnitude 10 quake. But there’s an upper limit to how much energy you can store in the rocks.

Very large earthquakes release more energy, but it is spread over a much longer section of fault line. It’s doubtful that there are any fault lines on Earth big enough to release a magnitude 10 earthquake, but if one happened, you could expect the ground to shake just as hard as a magnitude 9, but for a lot longer – perhaps as much as 30 minutes.


Image caption: A tsunami roars into the city of Miyako, following 2011’s earthquake.


luis villazon
Luis VillazonQ&A expert

Luis trained as a zoologist, but now works as a science and technology educator. In his spare time he builds 3D-printed robots, in the hope that he will be spared when the revolution inevitably comes.


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