SAN FRANCISCO -- Geologists were carefully watching the San Francisco Bay area Wednesday after a jolting 5.6 earthquake shook the area Tuesday night.
There were no immediate reports of damage but geologists were concerned it had created new "stress changes" along the fault-riddled area, the San Francisco Chronicle reported.
It was the strongest quake to hit the area since 1989 when one measuring 6.9 killed 63 people.
Near the epicenter, residents felt shaking for as long as 15 seconds from the movement 5.7 miles down, the newspaper said. Earth movements were felt as far north as Eugene, Ore., officials said.
David Oppenheimer of the U.S. Geological Service said it was wait-and-see situation as to what to expect Wednesday.
"We don't have a crystal ball and there's no way of knowing whether the one on Tuesday was a foreshock of another there or whether it was the main event," he said.
Copyright © 2007, by United Press International. All Rights Reserved.