Earthquake swarms at Mount St. Helens
Detailed Description
Graphic shows the earthquake swarm from June-July, 2019, compared to previous swarms detected in March 2019, 2017, 2016, and in 2014. The activity is likely the result of small-scale underground movements of hydrothermal fluids or gas — a sign that Mount St. Helens remains an active volcano.
Sources/Usage
Public Domain.