Section: Capital Region,  Page: D5

Date: Thursday, February 19, 2009

BERNE -- A small earthquake centered beneath Berne in rural Albany County was so slight that it passed with little notice.

The quake, which occurred at about 10:41 p.m. Tuesday, registered 2.7 on the Richter scale, said Mitchell Gold, a seismologist with the Lamont-Doherty Cooperative Seismographic Network. The group monitors underground activity in Connecticut, Delaware, Maryland, New Jersey, New York, Pennsylvania and Vermont.

Tuesday's quake was centered about 18 miles west-southwest of Albany. "This quake was fairly deep, so most people probably didn't feel anything," Gold said, "We have no reports that anyone called anything in to the state geologic service."

Major earthquake zones are formed by the boundaries of tectonic plates, massive formations of underground bedrock under pressure that float on a layer of deeper viscous rock and constantly grind against each other.

While upstate is far from the nearest plate boundaries in the center of the Atlantic Ocean and in the Caribbean Sea, the region is laced with underground faults, as well as many smaller or deeply buried faults that remain undetected.

Such a fault line, called the MacGregor Fault, runs from near Whitehall in Washington County south through Saratoga, where it merges with another fault -- the Saratoga Fault -- that runs south to Berne and the Helderbergs, where it peters out.

A small earthquake, with no reported damage and unnoticed by local residents, was reported in the Berne region in July 2007.

-- Brian Nearing