A strong earthquake centered near Cleveland shook parts of nine Great Lakes and Ohio Valley states, Canada and the Washington area yesterday, giving local residents who felt it something to talk about -- but not, perhaps, something to tell their grandchildren.

Though the quake measured 5.0 on the Richter scale, which indicates that ground movement could have caused considerable damage, there were no reports of injuries or serious structural damage from the quake, which occurred at 11:47 a.m. EST.

In the Midwest, where the earthquake force was strongest, office buildings and homes shook in several cities and towns. Some schools and businesses were evacuated as a precaution against structural damage, and more than a few employes fled into the streets fearing further jolts, according to police in several jurisdictions.

Locally, the earthquake was felt at many locations in the District, including the District Building and the Georgetown University Law Center. The tremors also reached from Alexandria to Hyattsville to Germantown, although some who felt them didn't know what was happening at first.

"I was frankly a little bit terrified," said Stan Keijci, a Fairfax County paging company official. He was in the middle of a meeting at his Rte. 1 office when the building lurched twice, and for a split second he thought it might be collapsing.

"I felt queasy," said Keijci, who credited his boss, Harry Brock, a native Californian, with being the first in a group of seven nervous employes to realize that the tremors were from an earthquake.

Those same tremors put a crack on the wall in Mayor Marion Barry's conference room and another in a wall of his outer office, both on the fifth floor of the District Building.

"We were all in a meeting with the mayor . . . which was getting very heated," said David Watson, legislative assistant to D.C. council member Nadine Winter (D-Ward 6). "People started to look around very discreetly, thinking 'Why are you pushing my chair?' Then we realized the whole room was shaking."

The meeting in the mayor's conference room concerned the efficiency of the District's 911 emergency call-in system, Watson said. "(Council member) Carol Schwartz (R-At Large) said maybe we should all call 911, and everybody laughed."

But for every person who felt the ground or floor move or who saw the blinds sway or an object topple, there were just as many here and elsewhere who said they felt nothing.

"We didn't feel it, either," said Gail Wendt, spokeswoman for the Reston-based U.S. Geological Survey. "Then the phone started ringing like crazy just before noon."

In Mentor, Ohio, located 30 miles northeast of Cleveland and considered the hardest hit by the quake, police Sgt. Roger Sielaff said the tremors lasted about five seconds and caused some minor problems in the town of 50,000. Roof tiles fell and the ceiling of one building fell in, he said, and four schools were closed for the day.

"There definitely were some strong vibrations," said Sielaff.

Elsewhere, according to the survey, buildings in Pittsburgh, Buffalo and Niagara Falls, Ontario, were shaken. Windows were shattered in some buildings in Detroit.

The survey said the quake's epicenter was located in Geauga County, Ohio, between the small towns of Chardon and Montville, about 30 miles east of Cleveland. It was felt in Pennsylvania, Kentucky, Ohio, West Virginia, Indiana, Illinois, Michigan, New York and Wisconsin as well as portions of Maryland and Virginia.

Before yesterday, there had been seven recorded earthquakes within 125 miles of the Cleveland area.

A Cleveland Electric Illuminating Co. spokesman said that the earthquake knocked out one generator of the company's Eastlake coal-burning plant but that other generators served as backup, according to a wire service report. The company was trying to determine yesterday whether the tremors damaged the Perry Nuclear Power Plant, which is under construction in Lake County, Ohio.

Seismic equipment located at Virginia Tech in Blacksburg, Va., recorded the quake's epicenter at 5.2 on the Richter scale, according to one report. A spokesman at the school said that was strong enough to break windows and knock things off shelves.

The Richter scale is a measure of ground motion as recorded on seismographs. Every increase of one on the scale means the quake's force is 10 times greater. A 3.5 Richter measurement indicates the quake can cause slight damage in a local area while a 7 reading is a major earthquake, capable of causing widespread heavy damage.

The San Francisco quake of 1906, which occurred before the Richter scale was devised, has been estimated at 8.3.

Neither the Midwest nor the Washington area is considered a serious earthquake zone. The most serious quake affecting this region occurred in 1886 near Charleston, S.C., and was estimated to have had an intensity of 10. Staff writer Virginia Mansfield contributed to this report.