So one of my interests is seismology and such, and I am by no means classically trained or an expert in the field, but I do know a thing or two about a thing or two. I was poking around my old friend Mt. Rainier because I was thinking of taking a trip to do another winter climb and I saw some activity on the cams the other day. (There was also a fatal avalanche recently as well)
So I looked at some of the other WA Cascade peaks, and Mt. Hood (who never has volcanoes) had 17 in November and a little more research turned up that quite a few Cascade peaks have "woken" up so to speak.
The "official" report from USGS is that the quakes are ice quakes, or rather, glacial movement occurring at the base of the glacier, hence the frequency of the seismologic activity being so low (like that of earthquakes). They also go on to say that because the signature doesn't resemble that of earthquakes, but rather what they've previously documented as ice quakes or glacial movement that that's what it has to be.
I'll just note two things: Rainier being active (and the Pac NW) at the level it currently is, in light of relatively recent volcanic activity worldwide, is something to take note of; anyone who knows the difference between harmonic events/tremors, glacial movement, tectonic earthquakes and volcanic earthquakes (shallow) can tell you by looking at these images that the official explanation is not exactly accurate.
There was a lot of concern following Japan's last quake that other areas in the Pacific would become active, most notable Juan de Fucas and the WA Cascades as they are by far the most "overdue" for an eruption. As you know, another earthquake occurred this morning off the coast of Japan.
This isn't to say the sky is falling, or that any volcano will erupt - in fact magma movement isn't uncommon and due to (quite) a lot of factors in the Pac NW it moves pretty often. It just doesn't often move around Mt. Rainier, cause tremors under the caldera, and activate Mt. Hood, Adams, Baker, Shasta etc.
I only bring it up because it's interesting to me and having lived in Seattle, the actual danger of an eruption makes St. Helens look like a kid pouring water into a sand castle.
Seattle news report:
http://www.king5.com/news/Thousands-...-95996979.html
Seismologic recorders:
http://old.pnsn.org/WEBICORDER/BETTE...web/index.html
(Check out RCM, RCS, and RVCX 24h, 1-3d)
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