New Activity at Mt. Rainier Confirmed to Be Seismic (...or ICE?), Right here on ATS!

reply to post by Olivine


Actually, Rainier is one of my "monitor live everyday" locations. And it has not been quiet, at all. Been seeing quite a bit showing up on the seismos, and registering on multiple stations. But I have been writing them off as ice quakes, so I really haven't said anything. There really is no need to, until I see a massive increase in frequency/magnitude, or tremor. Seen none of that in the last weeks/months. And if there was, believe you me I'd be starting a new thread faster than a seismic wave.

reply to post by TrueAmerican

Right. I've noticed a handful of very small quakes that show on Muir, Star, and Sherman, too.

But what I was thinking about was the repeaters--that were attributed to the glaciers. Have you noticed any of those types of signals in your monitoring, TA?

ETA:
I guess what I'm getting at, is that conditions must have been just perfect for the glaciers to exhibit that periodic, stick-slip behavoir, and this winter conditions are such, that the glaciers have stayed put, for the most part.
That is, unless there were repeating ice-quakes and I just missed them--which is entirely possible.

reply to post by Olivine


Well yes, of course I have picked them up. But I remain quiet. Again, as PNSN points out, they are primarily attributed to glacier movement. The big danger however, still lies in the problem of the glacier itself potentially masking, distorting, or event completely hiding, deeper seismic events. The scientists don't believe this to be a problem generally, and that the seismometers are sensitive enough to detect seismic events through the ice. So, I suppose we gotta go with that. Vigorous tremor and seismicity prior to eruptions can propagate to over 100 km, so plenty of other stations in the area would pick it up.

And let's face it- so far they have been right. There has been no discernible increase in activity. It has not erupted. I just wonder though if because of the ice cap, if gas/magma pressure could build up undetected, and it blow suddenly, with no warning whatsoever. This could be one of the ones to do something like that one day, cause of the ice cap.

reply to post by TrueAmerican


Ah, so they have occurred. Cool. Thanks for your reply, TA.
I'm off to check out what I can find...

I'm resurrecting this old thread because the thread's topic is still relevant. Here is the latest from the Cascades Volcano Observatory:

The onset of winter storms, especially in the past week, has generated a lot of noise on seismic instrumentation in the Cascades.
Although seismic activity at most volcanoes remains at background levels, the onset of these storms has induced notable minor seismic activity at Mount Rainier. A number of repetitive, very-small-magnitude quakes, commonly observed at Rainier once winter storms appear, began a couple of weeks ago and continue.
Ongoing research attributes these quakes to slip along the bases of the volcano's glaciers, not to volcanic activity.

Reading the last sentence in their statement, it seems there is yet to be unanimous consensus naming the glaciers as the source mechanism for the repeating quakes. If they were certain, wouldn't it read "Research shows these quakes are caused by glaciers", or something similar?

This image from Camp Schurman station on Rainier shows the nearly every-2-minute quakes.

(click for larger)
Here are the Rainier spectrograms for today.

Yesterday, there were strange "dots" on the spectros (for lack of a better term) for hours. Any idea what would cause this? Maybe something electrical? Here is an example of the "dots", located at 4Hz:

source

Recent EQ activity: The largest one in the area to date and the most active it's been.

Wondering your take on this, sources are saying they are tectonic not volcanic related and others are saying it's not a threat.

USGS Volcanoes 🌋 ‏ @USGSVolcanoes Jan 3 M3.9 #earthquake 12 km NE of #MountStHelens occurred at 12:36AM. @PNSN1 has located 15 aftershocks so far. Quake is tectonic - no sign that it's related to volcanic activity.

Source

Seismologists said they are confident the earthquake was a tectonic event and not related to magma activity within the volcano itself, but the location and strength of the quake were atypical.

"We have had a lot of small, tiny earthquakes in this zone. What we haven't had is an earthquake that size, a 3.9 in that area," said Bill Steele with PNSN.

UW seismologists say they log about 17 earthquakes a month on average near Mount St Helens. In the past month, they have tracked more than 80.

Source