Most of the U.S. volcanoes that have been making themselves known since spring woke up a bit, shook themselves off and then ...

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

What if the most telling indications of an impending volcanic eruption are buried deep under the ocean, or in a fleeting succession of tiny quakes that no one perceives? As volcanoes of the Pacific ...