Researchers started seismic monitoring at Mount Rainier in the 1970s, according to Iezzi, who works for the U.S. Geological Survey’s Cascades Volcano Observatory and said she conferred with other ...

Magma from the mantle finds its way to the surface, where it erupts as lava or ash and gas—sometimes in spectacular spurts, ...

The earthquakes are not currently a cause for concern, and do not indicate an impending eruption, the U.S. Geological Survey ...