Minor quake hits western Henrico

If you heard a boom Monday night in western Henrico County, you can tell your grandchildren you experienced an earthquake.

A magnitude 2.3 quake struck near the Henrico-Goochland County line eight seconds before midnight. Underground rumbling continued about 90 seconds, into early yesterday.

A quake that size is small and hits central Virginia about once a year, said Martin Chapman, director of the Virginia Tech Seismological Observatory.

"They are loud and last a few seconds and rattle windows," Chapman said.

The closest seismograph, at the University of Richmond, picked up the quake -- as did instruments from southeastern Pennsylvania to east-central North Carolina.

Dianne Pitts, a federal retiree who lives in northwestern Henrico, was reading the paper in bed when the quake hit.

"All of a sudden, the whole house shook, and the pull handles on my bedroom furniture rattled," Pitts said. "It was quite unsettling."

Others reported hearing a loud boom.

A complicated network of faults -- cracks in underground rocks -- causes an unusually high number of earthquakes between Charlottesville and Richmond. Researchers are trying to learn more about that process.

In 2003, two moderate-size earthquakes, magnitude 4.5, occurred in Goochland 12 seconds apart. They knocked items from shelves but caused no serious damage.

A magnitude 4.0 earthquake is 100 times more powerful than a 2.0.

Instruments have recorded more than 160 earthquakes in Virginia in the past three decades, but only about a sixth of the quakes were strong enough for people to feel them.

The state's biggest, a magnitude 5.8 quake in Giles County, hit in 1897 and was felt in 12 states. It broke off stone chimneys and muddied springs.

Contact Rex Springston at (804) 649-6453 or .