Seems there was a 4.5 earthquake in Virginia at almost 4pm this afternoon, just west of Richmond.

An FYI on VA earthquakes:

The largest event recorded was the Giles County earthquake in 1897. This event is estimated to have had a magnitude of 5.8 on the Richter scale. This is probably the third largest earthquake in the eastern United States within the last 200 years. The cause of the earthquake is not well understood.

More info on VA earthquakes.