A rare 4.1 magnitude earthquake rumbled the Philadelphia region Thursday afternoon shaking buildings and rattling nerves as far as 75 miles away from the epicenter.
The United States Geological Survey says the tremor struck at 4:48 p.m. in the Bombay Hook National Wildlife Refuge along the Delaware Bay. That's about 6 miles northeast of Dover, Delaware and the Dover Air Force Base.
The quake was shallow with a depth of 5 miles. It was first recorded with a magnitude of 5.1, but was revised to 4.1 around 5:10 p.m.
"It's a decently large earthquake for the area because they don't happen very frequently," USGS geophysicist Jana Pursley said. She expects the magnitude to continue to change as more data comes in to officials.
Reports of shaking flooded in from residents all over the region including Philadelphia, Atlantic City, New Jersey, Wilmington, Delaware, and as far west as Lancaster County, Pennsylvania.
Jill Tandy lives in Magnolia, Delaware, and she said she "felt it very bad. The house was shaking and dust was everywhere."
People said the shaking lasted for as little as 10 seconds and as long as 30 seconds. Rich Alexander in Haddon Township, New Jersey, said there was “major shaking for about 15 seconds. Many neighbors came outside saying, 'did you feel that?'.”
Dori Jacobson lives in Greensville, Delaware, and she said, "We knew it was something unusual. NO damage, but things shook for 5-10 seconds.”
Jay Nolt from Pennsville, New Jersey, said, "the dishes rattled and pictures moved on the wall."
Pursley said the cold soil and shallow nature of the quake allowed shaking to travel a longer distance as the energy encountered less resistance.
A seismograph at Holland Middle School in Bucks County picked up the quake, Science teacher Dave Curry said.
There are no reports of injuries or damage at this point. Pursley expects little to no damage to be found.
Thursday's quake is the strongest to hit the region since 1994 when a 4.6 magnitude tremor was recorded in Pennsylvania.
The last significant earthquake to rumble the East Coast happened in August 2011. That 5.8 magnitude quake was centered in Mineral, Virginia and left damage from Washington, D.C. to Philadelphia.