Mount St. Helens and Glacier Peak are the only volcanoes in Washington state that have been explosive in the past 15,000 years.
On November 25, 2015, four earthquakes – from M1.4 to M3.5 – struck about three miles from Glacier Peak. And that’s a place where there haven’t been a lot of magnitude 3 earthquakes in the past.
The quake swarm, recorded roughly 19-21 miles east-southeast of the town of Darrington, started with a M3.1 earthquake occurred at 12:11 p.m followed by a second M3.5 tremor at 1:20 p.m. The two last ones – resp. M1.6 and M1.4 – occurred at 2:33 p.m and 3:44 p.m.
Magnitude 3 earthquakes happen in Washington and Oregon a number of times per year, but the one thing that makes these last 2 potentially interesting is the fact the tremors were close to Glacier Peak.
The last time there was a magnitude 3 in the vicinity was in 1991. So what is going on at Glacier Peak volcano? The last time Glacier Peak erupted was 1,100 years ago.
Beginning of this month the Kalama River turned grey. A sign of an imminent eruption at Mount St Helens?