I believe the new seismic monitors USGS instaled at Yellowstone are only to keep the public happy. These "new" seismograms of theirs show 220% less detail than the old ones did (659 pixels to show 1800 seconds of data, or 2.731 seconds per pixel, whereas the old ones showed 1.25 seconds per pixel). So you can really forget about seeing harmonic tremors on them now.
The M6.3 earthquake along the Aleutian trench made the earth ring like a bell. In my opinion made the magma there slosh.
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