They were all within 8.2 miles of the volcano, most of them closer.

Mount Rainier is one of Washington's active volcanoes, but earthquake experts say this swarm of quakes is not cause for alarm.

This isn't the type of earthquake activity that would lead up to an eruption, said Harold Tobin, director of the Pacific Northwest Seismic Network, which is based at the University of Washington. They track earthquakes across the Northwest.

The quakes have been small and fairly shallow. For example, a 0.4 magnitude Monday afternoon and a 1.2 magnitude that morning.

"For us to start to be concerned about an imminent eruption we would have to see a sort of persistent swarm of earthquakes," Tobin said. "We would tend to see them extending up and down in depth, suggesting that there's magmatic movement."