University of Canterbury doctoral student John Holdaway has worked out that the September 4 quake released 2.8 quadrillion joules of energy. A quadrillion is one followed by 15 zeroes.
That dwarfed the 92 trillion joules combined unleashed by the 1011 aftershocks to noon yesterday, which was only 3.2 per cent of the total energy released.
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Holdaway estimated the September 4 quake involved enough energy to power Christchurch for two weeks.
Visiting professor Kevin Furlong, of Penn State University, used a different measure.
It was the same as eating about two billion chocolate bars, or about 500 bars for every man, woman and child in New Zealand, eaten in about 25 seconds, he said.
Thats a lot of power, and chocolate.. no wonder the earth moved so much, and for so long.
Next time can we just have the chocolate!