Latest Earthquakes at Mount St. Helens

Time vs. Depth plots of Mount St. Helens earthquakes for the past year.

Time-Depth, map, and cross sections of Mount St. Helens earthquakes for the past decade.

Webicorder Records, including seismometers near Mount St. Helens.

Graphs show average number of events occurring per day (blue) and average seismic strain energy release (square root of seismic energy) per day (red). Seismic strain energy is computed from earthquake magnitude and is more representative of the changes in the deep magma system than simply number of locatable events alone. The graphs show data over the last 12 months and are calculated using a 7 day running average. Each vertical grid line corresponds to the first day of of each month.

Note that the strain energy release curve does not mimic the daily number curve exactly. This is because the strain energy curve is dominated by the larger events while the daily number curve includes even very small earthquakes (Mag < 0) which contribute very little strain energy release.

Back to:
UW Dept. of Earth and Space Sciences
PNW Earthquake Info