Note that the reported magnitude of 8.9-9.1 is on the moment-magnitude scale; the article you're looking at there is about the Richter scale, which isn't used as much these days.
By my understanding (IANAgeologist) the scales are calibrated to be roughly equivalent for medium-sized quakes but maybe not for large ones.
They've upgraded it to 9.0 now. Also, there was *another* 6.6 in central Japan not long ago; this one wasn't an aftershock, it's on an entirely different fault line.
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(no subject)
Date: 2011-03-11 02:59 pm (UTC)(no subject)
Date: 2011-03-11 03:16 pm (UTC)Also according to Wikipedia, one happens a year, but I find that hard to believe.
(no subject)
Date: 2011-03-11 03:28 pm (UTC)(no subject)
Date: 2011-03-12 01:21 am (UTC)By my understanding (IANAgeologist) the scales are calibrated to be roughly equivalent for medium-sized quakes but maybe not for large ones.
(no subject)
Date: 2011-03-11 03:39 pm (UTC)(no subject)
Date: 2011-03-11 03:41 pm (UTC)(no subject)
Date: 2011-03-11 03:53 pm (UTC)(no subject)
Date: 2011-03-11 04:36 pm (UTC)(no subject)
Date: 2011-03-11 04:35 pm (UTC)(no subject)
Date: 2011-03-11 06:25 pm (UTC)(no subject)
Date: 2011-03-11 07:33 pm (UTC)(no subject)
Date: 2011-03-11 09:58 pm (UTC)(no subject)
Date: 2011-03-11 10:16 pm (UTC)