Earthquake Swarm Detected at Mount St. Helens

There have been more than 130 earthquakes detected below Mount St. Helens, according to scientists from the United States Geological Survey.

The quakes, which have been increasing - there were nearly 40 last week - have been too small to feel at the surface.

The strongest quake was a 1.3 magnitude. Most have been .5 or less.

Scientists say that the quakes are "volcano-tectonic" in nature; in other words, caused by a slip on a small fault.

They say it is similar to a swarm that occurred in 2013-2014 and does not appear to be indicative of any imminent eruption.