Seismicity at Mount St. Helens from 1980-2014.

Detailed Description
Seismicity at Mount St. Helens (MSH) from 1980-2014. Each earthquake is a filled round circle. The size of the circle reflects the magnitude of the earthquake. From 2008 to 2012, the range of magnitude is -1.0 to 2.1. Depth is in kilometers (one km is equal to 0.62 miles so 2 km, for example, is 1.24 miles).
Sources/Usage
Public Domain.
S. Moran