Mount St. Helens sees spike in seismic activity

400 earthquakes have been recorded under Mount St. Helens since mid-July, according to the U.S. Geological Survey.
Published: Nov. 8, 2023 at 12:07 PM PST
Email This Link
Share on Pinterest
Share on LinkedIn

SKAMANIA COUNTY, Wash. (KPTV) - 400 earthquakes have been recorded under Mount St. Helens since mid-July, according to the US Geological Survey (USGS).

This is the longest series of tremors since the volcano’s last eruption ended in 2008.

Luckily, a new eruption doesn’t appear to be happening soon.

“Mount St. Helens has had a slight uptick in earthquakes, have you noticed? Most are small (less than M1.0) & not felt at the surface. No cause for concern right now - no significant changes in ground deformation or gases. Volcano remains at normal (green) background levels,” the USGS said in an update posted to its website.

“Since mid-July 2023, over 400 EQs have been located by @PNSN1. Most recently, there have been about 30 located EQs per week. To compare, since 2008, on average about 11 earthquakes have been located per month at Mount St. Helens.”

According to the USGS, there are no indications of a “imminent eruption.”

Despite not erupting since 2008, Mount St. Helens is regarded as one of the most dangerous volcanoes in the United States.

On May 18, 1980, the volcano had its most famous eruption, which destroyed 210 square miles of surrounding forest and claimed the lives of about 60 people.

The volcano saw a spike in activity before this eruption. Several earthquakes shook the area on March 20 of that year. The earthquakes increased until March 27, when there was a small eruption. The amount of volcanic activity only kept rising until there was a massive magma buildup under the volcano.

The surrounding area was rocked by an earthquake of magnitude 5, which set off the main eruption on May 18.

As of right now, the volcano is still active, and geologists expect it will erupt again one day.

However, the USGS stated that a brief spike in seismic activity in St. Helens is rather typical.

“The current seismicity represents the largest short-term increase in earthquake rates since the last eruption ended in 2008,” the USGS said. “However, longer duration sequences with more events occurred in 1988-1992, 1995-1996 and 1997-1999. None of the sequences in the 1980s and 90s directly led to eruptions.”