[math-fun] Earthquake magnitudes
I saw a press conference on the internet where the Chinese govt officials were saying that the 2008 Olympics were safe, because the facilities were constructed to survive an 8.0 earthquake. I also understand that the recent Sichuan quake was magnitude 7.9. If I understand the Richter scale, it is log_10(amplitude), so amplitude 8.0 should be 26% greater than amplitude 7.9. http://en.wikipedia.org/wiki/Richter_scale Is 26% much of a safety margin?
On Wed, May 14, 2008 at 11:11 AM, Henry Baker <hbaker1@pipeline.com> wrote:
I saw a press conference on the internet where the Chinese govt officials were saying that the 2008 Olympics were safe, because the facilities were constructed to survive an 8.0 earthquake. I also understand that the recent Sichuan quake was magnitude 7.9. If I understand the Richter scale, it is log_10(amplitude), so amplitude 8.0 should be 26% greater than amplitude 7.9.
http://en.wikipedia.org/wiki/Richter_scale
Is 26% much of a safety margin?
That depends on your analysis. The really essential thing to know is the probability that an earthquake of that magnitude will occur. It's certainly fallacious to think that just because a 7.9 magnitude earthquake occurred last week there is likely to be one of at least that magnitude in, say, the next 50 years. Victor
_______________________________________________ math-fun mailing list math-fun@mailman.xmission.com http://mailman.xmission.com/cgi-bin/mailman/listinfo/math-fun
participants (2)
-
Henry Baker -
victor miller