USGS: East Coast Quake Unusual but "Not a Surprise"

Pasadena - The magnitude-5.8 earthquake that rattled the East Coast today is an unusual occurrence and the largest temblor to hit the region since the late 19th Century, but the area has had its share of quakes in the past, seismologists at the U.S. Geological Survey in Pasadena said today.

The quake struck just before 2 p.m. Eastern time, centered 38 miles northwest of Richmond, Va. The quake was felt up and down the East Coast -- most notably in Washington, D.C., but also as far south as Atlanta.

"That's a feature of earthquakes on the East Coast," USGS seismologist Lucy Jones said. "The rocks there are colder and older and harder than the rocks in California, do a better job of transmitting energy. So the same size earthquake is felt over a much wider area along the East Coast.

"It does sound like there has been some damage," she said. "I would expect that most of the damage would be down in the area of the epicenter, east of Charlottesville and west of Richmond."

The quake came as a definite surprise to people up and down the East Coast, but the area does have a history of seismic activity.

"This event happened within the Central Virginia Seismic Belt, and there have been over a couple hundred earthquakes within that belt since the late 70s when they started doing more detailed recording of earthquakes," USGS geophysicist Ken Hudnut said. "The largest in recent times was a four and a half in 2003, but there was one in the late 1800s that may have been a magnitude-4.8, so it's not unprecedented to have earthquakes in this seismic belt between Charlottesville and Richmond, but this is the largest within that zone."

Kate Hutton, a seismologist at Caltech, said today's quake was the largest on the East Coast since 1897, when a magnitude-5.9 quake struck in Virginia.

Jones noted that the USGS headquarters in Reston, Va., was evacuated after the quake to be checked for damage.

"One time, an earthquake there is quite unlikely," Jones said. "The fact that eventually there's an earthquake there is not a surprise, because it is an area that's had earthquakes in the past. This is a recognized seismic zone, meaning it has had more earthquakes than we normally see out on the East Coast."