It was mild by West Coast standards, but the East Coast is not used to quakes at all, and this one briefly raised fears of a terror attack less than three weeks before the 10th anniversary of Sept. 11.
Frightened office workers poured out of New York City skyscrapers, and parts of the White House, Capitol, and Pentagon were evacuated.
New York's police commissioner, Raymond Kelly, was meeting with top deputies planning security for the 9/11 anniversary when the shaking started. Workers in the Empire State Building spilled into the streets, some after descending dozens of flights of stairs.
"I thought we'd been hit by an airplane," said one worker, Marty Wiesner.
At the Pentagon, a low rumbling built until the building itself was shaking, and people ran into the corridors. The shaking continued, to shouts of "Evacuate!" The main damage to the building came from a broken water pipe.
Two nuclear reactors at the North Anna Power Station, in the same county as the epicenter, were automatically taken off line by safety systems, said Roger Hannah, a spokesman for the Nuclear Regulatory Commission.
The National Park Service initially evacuated and closed all monuments and memorials on the National Mall, but many were later reopened.
An inspection turned up cracks "at the very, very top" of the Washington Monument, Park Service spokesman Bill Line said. The 555-foot-tall stone obelisk will remain closed and "could be closed for an indefinite period of time," the Washington Post reported.
At the majestic Washington National Cathedral, at least three of the four pinnacles on the central tower fell off, a spokesman said. The pinnacles are the top stones on the cathedral's towers. Cracks also appeared in the flying buttresses at the cathedral's east end, and the building was closed to visitors.
When the quake struck, Sen. Chris Coons (D., Del.) was walking up Capitol Hill on his way to preside over a pro-forma session of the Senate. The 22-second session did take place, not at the evacuated Capitol but at the Postal Square Building, next to Union Station. By late afternoon, the Capitol was reopened for people to retrieve their belongings.
Several airports, including Philadelphia International, briefly halted flights to ensure there was no significant runway damage. At Reagan National Airport in Virginia near Washington, alarms went off and objects tumbled from shelves.
Amtrak said its trains along the Northeast Corridor between Baltimore and Washington were operating at reduced speeds, and crews were inspecting stations and railroad infrastructure before returning to normal. Trains that were headed south toward Richmond and beyond switched to diesel power and off electric lines as a precaution. For passengers, it meant no air-conditioning or working toilets.
On Wall Street, the floor of the New York Stock Exchange did not shake, officials said, but the Dow Jones industrial average sank 60 points soon after the quake struck. The Dow began rising again a half-hour later and finished the day up 322 points.
The quake was felt as far north as Toronto, as far west as Indiana and Kentucky, and as far south as Atlanta and Savannah, Ga. It was also felt on Martha's Vineyard, off Massachusetts, where President Obama is vacationing. He was starting a round of golf when the quake struck, but he didn't feel it, spokesman Josh Earnest said.
Obama put the golfing on hold and led a conference call on the quake with top administration officials, including Homeland Security Secretary Janet Napolitano, National Security Adviser National Security Adviser Tom Donilon, and Craig Fugate, administrator of the Federal Emergency Management Agency. Obama was told there had been no major damage reported and asked for regular updates.
Around Mineral, a town of 430 people close to the quake's epicenter, people milled around in their lawns, on sidewalks and parking lots, still rattled and leery of reentering buildings.
All over town, masonry was crumpled, and the contents of store shelves were strewn on the floor. Several display windows at businesses in the tiny heart of downtown were broken and lay in jagged shards.
Carmen Bonano, who has a 1-year-old granddaughter, sat on the porch of her family's white-frame house, its twin brick chimneys destroyed. Her voice still quavered with fear.
"The fridge came down off the wall and things started falling," she said. "I just pushed the refrigerator out of the way, grabbed the baby and ran."
Mayor Pam Harlowe told McClatchy Newspapers late Tuesday afternoon that the town hall was one of a small number of buildings still deemed unsafe.
The Geological Survey put the quake in its yellow-alert category, meaning there was potential for local damage but relatively little economic damage.
It said the quake was 3.7 miles beneath Earth's surface, but scientists said they may never be able to map the exact fault. Aftershocks may help to outline it, said Rowena Lohman, a seismologist at Cornell University. There were at least two aftershocks, magnitudes 2.2 and 2.8.
The last quake of equal power to strike the East Coast was in New York in 1944. The largest East Coast quake on record was estimated at up to 7.3, in South Carolina in 1886. In 1897, a 5.9 quake was recorded at Giles County, Va., the largest on record in that state.
A 5.8 quake releases as much energy as almost eight kilotons of TNT, about half the power of the atomic bomb dropped on Hiroshima, Japan. The quake that devastated Japan in March released more than 60,000 times as much energy as Tuesday's.
The Virginia quake came hours after a magnitude-5.3 earthquake late Monday night in Colorado toppled groceries off shelves and caused minor damage to homes in the southern part of that state and northern New Mexico.
The Colorado quake struck about nine miles southwest of the town of Trinidad, with an estimated depth of 2.5 miles, according to the Geological Survey's National Earthquake Information Center in Golden. Aftershocks continued Tuesday, but no injuries were reported.
Earthquake Insurance Is 'Very Infrequent'
Homeowners won't be covered by standard property-insurance policies if there's any damage from Tuesday's earthquake.
Earthquake protection is generally excluded from standard homeowners' policies, and consumers must buy coverage either as
a separate policy or an endorsement to
an existing one, said Michael Barry,
a spokesman at the Insurance Information Institute in New York.
Most people who buy coverage live in earthquake-prone states, such as California and Missouri, said Janece White, a vice president at Chubb Corp., which insures commercial property and
"It's very infrequent" that East Coast residents buy earthquake coverage, since during their lifetimes there has never been a temblor that warranted it, White said.
Consumers who have so-called floaters to insure valuables such as fine art or all-risks-contents policies generally will be reimbursed for quake damage to such items, White said.
Dick Luedke, a spokesman for State Farm Mutual Automobile Insurance Co, said, "A lot of people do purchase event protection after an event occurs because they realize, 'Hey, that could happen to me.' "
Luedke said that homeowners generally can't buy earthquake coverage for as many as 60 days after a quake, because of the potential for aftershocks.
- Bloomberg News
This article includes information from Bloomberg News.