Some Shaking Going on at Mount St. Helens
The United States Geological Service (USGS) has been monitoring an uptick in earthquake activity at Mount St. Helens. The frequency of temblors has been higher than normal since mid-July.
More than 400 earthquakes have been detected by the Pacific Northwest Seismic Network since July 15, 2023. About 30 quakes per week have been recorded recently.
This is the longest period of short-term activity since the mountain last erupted in 2008, but the USGS says it's not a concern as most of the quakes measure a magnitude of 1.0 at depths of 1.2 to 3.7 miles below sea level. There was a magnitude 2.4 quake on August 27, 2023.
In 1988-1992, 1995-1996 and 1997-1999, USGS reported longer duration sequences with more events. None of the sequences in the late 80's and 90’s directly led to eruptions.
Looking at Mount St. Helens Over the Years
Gallery Credit: Aj Brewster