Volcanoes in the United States that have been active since spring woke up, brushed themselves off, and then went back to sleep. Two volcanoes, one in Alaska and one in Hawaii, are experiencing active eruptions that are minimal and not very dangerous.

These 10 U.S. states experience the highest number of earthquakes, shaking their ground quietly yet consistently, reminding us of the hidden tectonic forces underfoot and the constant motion of Earth’s crust across America.

Seismicity has decreased” from 30 events per hour at the peak to a few per hour as of Saturday morning, the U.S. Geological Survey said Saturday.

The series of earthquakes is the first major swarm of seismic events since 2009. Is it safe if you’re planning on visiting?

The United States and Japan concluded a weeklong disaster-response exercise that simulated a magnitude 7 earthquake, the first to bring together U.S. Forces Japan and the country’s newly formed Joint Operations Command.

This is now the largest recorded earthquake swarm at Mount Rainier since seismic monitoring at the volcano began in 1982, the Cascades Volcano Observatory said. With quakes ongoing, the swarm has already surpassed a major event in 2009 “in terms of magnitude, total events, event rate, and energy release.”

Mount Rainier, the active volcano towering above southwestern Washington state, started rumbling — very lightly — on Tuesday. A swarm of small earthquakes was detected under the mountain triggering focused monitoring from officials. But researchers have determined there is no current threat of an eruption.

A seismologist from Seattle discussed recent volcanic activity across the United States. Here's what you should know.