North Jerseyans reported briefly feeling tremors from a 4.1-magnitude earthquake that occurred near Dover, Delaware shortly before 5 p.m. Thursday.
The quake officially was recorded at 4:47 p.m. 10 kilometers east/northeast of Dover, according to the U.S. Geological Survey .
"Lasted five seconds or so," Eugene Bazzarelli of Wood-Ridge said.
Shock waves were also felt in New York City and Philadelphia.
Some buildings shook in and around Dover, but no damage was reported.
The Geological Survey initially reported the magnitude at 5.1 but then revised that figure, first to 4.4 and then 4.1 on the Richter Scale .
Northeast U.S. earthquakes aren't common but do happen.
The last one of note struck six years ago in Virginia, registering 5.8, causing extensive damage and sending shock waves as far north as New Jersey and New York.
It also damaged structures in Maryland, as well as the Washington Monument.
New Jersey officially has had more than 30 earthquakes since then, according to the Geological Survey. Most weren't even felt, the federal agency reported.
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