Two small earthquakes have occurred near Mount Baker in November, the second and third detected in 2014. Magnitudes were 1.9 and 1.1. Though small, they were still among the largest earthquakes at Cascade volcanoes in the past month. They are not considered anything other than normal.
Locations: http://pnsn.org/volcanoes/mount-baker
1. On November 5th, there was an M 1.9 event just after midnight at or near the terminus of the Thunder Glacier, 4 km west of Mount Baker’s summit. Though small, this is still among the largest earthquakes recorded at the volcano in the past 9 years (see graph at the link above- scroll down there in the right margin’s list. Pacific Northwest Seismic Center’s report page: http://pnsn.org/event/60917886#overview Note the uncertainty in depth of this seismic event, 31.61 km vs. horizontal error, only 0.6 km. The waveforms are here: http://pnsn.org/event/60917886#waveforms Note that the top two graphs are from the nearest seismic stations, MBW (2.8 km distant) and SHUK, near the Mount Baker ski area, 16.1 km distant.
2. On November 12th, an M 1.1 earthquake was centered beneath the right valley wall of Park Creek on the east flank, nearly 10 km from the summit. Pacific Northwest Seismic Center’s report page: http://pnsn.org/event/60914762#overview The event was reported at 4.5 km depth, but note the uncertainty in depth of this seismic event is less than the other, merely 15.87 km. The horizontal error is nearly 1 km. The waveforms are here: http://pnsn.org/event/60914762#waveforms MBW (15.8 km distant) and SHUK, near the Mount Baker ski area, 12.6 km distant.
In contrast, only one small earthquake was reported in 2013 (and that was likely due to blasting), and one each in 2012 and 2011.
For a comparison of relative seismicity at Cascade volcanoes over the past 30 days, visit this page: http://pnsn.org/volcanoes
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