reply to post by MurderCityDevil
Hope the OP doesn't mind my answering you.
This info is readily available on the Web. I generally use the USGS site because its maps are updated almost real-time and they also have plenty of
technical info for those who want it. Just go to [this link for USGS]
and you can
click on the interactive map to get details of quakes.
Quakes in the 6 to 7 range are not all that unusual in the island chain west of mainland Alaska, but further down the coast around Vancouver quakes of
that size are comparatively rare. In fact -- and I monitor USGS daily -- I don't recall any in the plus-6 range in that region in the past year.
Okay, they may have been one and I simply have forgotten it but there have been three
in that area (and in that range) in less than a week and
that is really something that caught my attention.
However, the one off the coast of Oregon (almost straight West of Eugene) concerns me a lot more, because a 6-plus there is very unusual indeed. There
are plenty there in the 3 to 4.5 range and occasionally even low-5s, but a 6.3 is significant.
The reason it's a worry is because there is a stuck plate boundary there. One edge of the Juan de Fuca plate has not moved significantly for around
300 years. The last time it did let go and release its energies was on 26 Jan 1700, the date known precisely because the Japanese -- way across the
ocean -- recorded details of the tsunami that reached them several hours later. Local studies in coastal Oregon indicate that this quake produced a
tsunami that flooded into near-coastal lakes up to 30 metres high. (That's close to 100 feet.) Authorities in the Oregon coastal regions are well
aware that sooner or later this fault will let go again and (past quakes being a fair guide), trigger a quake around a mag 9.0 and a very serious
I find it puzzling that (at least here on satellite TV like CNN) so little has been said about this series of quakes. True, it could well be that
nothing serious will ensue in the near future, but on the other hand these quakes could be a precursor of a large one. Please note that this is not
"the big one" relating to the San Andreas group of faults that so many people are waiting for. This is quite separate, for some reason largely
ignored, and potentially far more devastating.
Don't think I'm crying doom and gloom. I'm not. The fact is that around once every 300 years that stuck plate lets go, and it's pretty well due.
That's all. It could happen tomorrow or it could be in 100 years from now. But the series of significant quakes in that region (along connecting
plate boundaries) is bothersome, to put it mildly.
Edited to add: Apologies to other posters for any material I've rehashed. Just tying a few bits and pieces together for those who might come in late
[edit on 11-1-2008 by JustMike]