On October 29, 2019, a swarm of more than 10 earthquakes rattled under Mt. Rainier’s NE flank.
This volcano is not particularly explosive. But volcanologists are unequivocal in her assessment: Rainier is one of the most dangerous volcanoes in the world and probably the most dangerous U.S. volcano… It’s a huge concern.
The swarm started on October 28 with two earthquakes and continued over on October 29 with 10 quakes. On October 30, another shake was reported by the seismometers (triangle on the map above).
These seismic events under Mt. Rainier’s NE flank appear to be tectonic, not at all volcanic.
But the tremors may be the result of activity on a tectonic aspect of the conduit’s location.
And given their depths (0.6-1.0 miles), times (between 1am and 11 am) and energies (M0.6 to M2.1) they may all have occurred on the same fault plane.
But there are actually no specific known faults that might be associated with this activity in the current literature.
Maybe you can find a map of earthquake fault lines on Mount Rainier?
So what are these earthquakes under Mount Rainier NE flank?