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I know the Richter magnitude scale is often used for measuring the strength of earthquakes. At the same time, explosive/destructive releases of energy are often quoted in equivalent amounts of TNT. Is there some way to relate these two scales? Or are they not equivalent?

It's especially confusing since the Richter scale doesn't seem to go very high. Is a magnitude 8 earthquake really only 4 times worse than a magnitude 2? Or would converting these numbers to TNT equivalents be more revealing?

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Hi hatava. I'm closing this question (v1) as too localized since a simple Google search seems to provide the answer. – Qmechanic Apr 16 '13 at 18:52
Although, to be fair, this question could be modified to invite discussion of the MMS being quoted as Richter despite the disparity between the two; also, since the MMS is not exactly an energy scale, an answer that addresses all of these issues in the context of TNT approximations would give more information than that wikipedia article (which I just read). – Trevor Alexander Dec 28 '13 at 10:09

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