2.1-Magnitude Earthquake Rattles Somerset County

SOMERSET COUNTY, NJ — A preliminary 2.1-magnitude earthquake rattled Somerset County on Friday night, one of dozens of aftershocks to hit the state since April 5's 4.8 temblor.

The United States Geological Survey said the quake struck shortly after 10 p.m. about 6 km west-southwest of Gladstone.

The aftershock is one of several to hit the area this week. The USGS has recorded numerous small quakes in Somerset and Hunterdon counties, all originating near Califon, Whitehouse Station, or Lebanon.

The aftershocks come two weeks after a 4.8 magnitude quake rattled the tri-state area. The USGS said more than 42 million people might have felt the initial quake, centered about 45 miles west of New York City and 50 miles north of Philadelphia.

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Earthquakes are less common on the eastern than western edges of the United States because the East Coast does not lie on a boundary of tectonic plates. But 13 earthquakes of magnitude 4.5 or stronger have been recorded since 1950 within 311 miles of April 5's temblor, the USGS said.

The strongest was a 5.8-magnitude quake in Mineral, Virginia, on Aug. 23, 2011, that jolted people from Georgia to Canada.

Did you feel Friday's aftershock? Report it to the USGS for tracking purposes.