The U.S. Geological Survey says the aftershocks around the central Virginia epicenter ranged in magnitude from 4.2 to as little as 2.2 since the strongest earthquake to strike the East Coast since World War II.
There's a chance there were even more aftershocks; the USGS is still compiling data from groups that monitor local seismographs around the country.
Amy Vaughan, a geophysicist with the Earthquake Information Center in Colorado, says the number of aftershocks so far has been remarkably low.
Vaughan says the agency isn't sure what to expect, but it's likely there will be some more for days, if not weeks. Typically, the larger the quake, the longer and the greater extent of aftershocks.