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Q & A: Energy release of 2011 Japanese earthquake

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Most recent answer: 03/12/2011
How much energy in Joules was relased during the 2011 Japan earthquake and to what can with compare it?
- Anonymous
I checked a standard Wikipedia article:

It seems that a Richter magnitude of 8.9 corresponds to about 1018 Joules. [Now upgraded to 9.0, a bit larger.]

For a comparison, I've just grabbed the number for the high-explosive equivalent from the same wikipedia article. It's equivalent to around a thousand of the typical hydrogen bombs in the arsenals of the big nuclear powers. Fortunately the earthquake's energy is not nearly as focused on human beings and their structures as the bombs' energy would be. Thus the death toll is likely to be between ten and one hundred thousand (probably toward the low end of that), in contrast to a much larger death toll from a single bomb.  Also, it looks as if  (knock on wood) the net release of long-lived radioactivity from damaged nuclear power plants may be fairly small, unlike the massive fallout from the use of that many bombs. [Note: That last sentence is starting to sound too optimistic, although even a serious Chernobyl-like release of radioactivity would be small compared to the fallout from a nuclear war.]

Mike W.

(published on 03/12/2011)

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