Mount St. Helens Recharging, Volcano Could Blow Again

Mount Saint Helens, the infamous Washington volcano that erupted dramatically in 1980, has been exhibiting significant and consistent activity recently, as reported by the US Geological Survey. The volcano, which stands at an elevation of 8,363 feet, has been the epicenter of approximately 350 earthquakes since the beginning of February, with a peak of 38 occurring in the first week of June.

While most of these seismic events were not perceptible, one earthquake on May 31 registered a 2.0 on the Richter scale. This is less than half the magnitude of a 4.8 quake that shook New York in April, which was not particularly devastating. However, the recent increase in seismic activity at Mount Saint Helens, particularly since 2023, represents the largest short-term surge in earthquake rates since the volcano’s last eruption in 2008, according to the USGS’ Cascades Volcano Observatory in Vancouver, Washington.

The 2008 eruption, although relatively minor, marked a four-year period of buildup. The eruption was powerful enough to produce enough ash to cover a seven-lane highway three feet thick from New York City to Portland, Oregon, according to the USGS.

Small earthquakes often indicate that a volcano is pressurizing its stored magma, a process known as “recharging.” During this process, magma slowly rises through the lower crust and accumulates in a reservoir about 2.5 to 6 miles below sea level. When magma enters this upper reservoir, it increases stresses that can lead to earthquakes.

Despite the increased seismic activity, experts are reassuring the public that this is a natural occurrence and does not necessarily indicate a high risk of another eruption. High rates of seismicity, interpreted as recharge, have been observed in the past at Mount St. Helens and at other volcanoes and can continue for many years without an eruption, the observatory noted.

At present, no significant changes have been observed in other monitoring parameters and there is no change in alert levels. Mount St. Helens remains at normal, background levels of activity.