Hey now, our 5.8 isn't too far from your 6.3!
Well, it's logarithmic, right? I mean, not too far, but further than it might seem.
From wiki:
So it's still five times larger amplitude than ours.
Yeah. And even then, magnitude often doesn't really explain it enough.
The original 7.1 in NZ didn't do too much damage and no one was killed. The aftershock was weaker but shallower and centred directly beneath a major city. The damage was much more serious and there were quite a few fatalities. So magnitude doesn't tend to be a reflection of actual damage; The
Mercalli Intensity Scale can be a better gauge for this.
However,
peak ground acceleration is probably the best measurement, as it is used in building codes to reflect true forces on structures. This was
huge in Christchurch's February aftershock. It was 2.2g (
That's twice the force of gravity!) at the epicentre and averaged 1.8g - this would completely level many of even the most modern cities. By comparison the Haiti earthquake was a 7.0 magnitude but averaged 0.5g in ground acceleration. A lot of the differences in result can be put down to building standards.
...sorry... I've just read a lot about this stuff in the last year...
Regardless of all this, its great no one was badly hurt in the US and no major damage was done. I can tell you the numerous, ongoing problems of a serious earthquake are
absolutely mindboggling, and it really is a blessing to be spared it. Its hard enough here, I can't possibly imagine what its been like in Japan and Haiti.
