Earthquake shakes city
Published 11:59 pm Tuesday, August 23, 2011
The second most powerful earthquake in Virginia’s history hit the state Tuesday afternoon, shaking buildings throughout Suffolk.
The magnitude-5.8 earthquake was centered about six miles southwest of Mineral, Va. It was 66 miles northwest of Richmond.
The temblor struck at 1:51 p.m. and was about 3.7 miles deep at its epicenter. Shaking reportedly was felt as far north as Massachusetts.
There were no reports of injuries in Suffolk, but some government buildings were damaged. Interior and exterior walls at the city assessor’s office cracked, city spokeswoman Debbie George said, and existing cracks in walls and floors expanded at the municipal building. Some damage was also reported at the Whaleyville fire station.
“I think that we were very fortunate,” George said. “There was no major damage reported in the city, nor were there any injuries.”
George added that there were no reports of damages to roadways, dams or water production facilities.
Emergency dispatchers answered calls from residents reporting that their homes and businesses shook, George said. They were followed by burglar alarm calls triggered by the quaking.
Firefighters battling the fire in the Great Dismal Swamp National Wildlife Refuge were not affected, said public information officer Mark Nelson.
“They felt the earthquake a little bit here in our information trailer,” Nelson said. “There was no other impact.”
In Isle of Wight County, officials evacuated the courthouse shortly after the event. There were no reports of damage, he said.
“I think other than the shocked looks on folks’ faces, pretty much everybody fared well,” said county spokesman Don Robertson. “I think most people were really surprised and not sure about what was happening until after the fact.”
Three aftershocks — magnitude 2.8, 2.2 and 4.2 — struck at 2:46, 3:20 and 8:04, respectively. Officials warned they could continue for several days.
Gov. Robert McDonnell’s office issued a statement saying state agencies were cooperating with federal and local officials to assess the situation.
“All indications are that emergency response plans and orderly evacuations have gone well today,” McDonnell said. “All resources of the Commonwealth have been put on alert to assist in any way necessary as we move forward.”
The quake nearly broke the record for the largest earthquake in Virginia, which occurred on May 31, 1897 in Giles County. Shaking from that event changed the flow of Appalachian springs and caused the earth’s surface to roll “in an undulating motion,” according to the U.S. Geological Survey. Aftershocks continued for a week after that event.
While Virginia’s earthquake risk doesn’t compare to that the West Coast or even the Midwest, temblors in the Old Dominion are not unheard of.
Earthquakes occur when the two sides of a fault suddenly slip past each other, according to the U.S. Geological Survey. The fault is a fracture in the earth along which the blocks earth’s plates have moved relative to one another. The plates are always slowly moving, but sometimes get stuck at their edges. When the stress becomes too much to bear, the earthquake releases energy in waves that travel through the earth’s crust.
Virginia has two seismic zones, the Central Virginia Seismic Zone, where Tuesday’s event was centered, and the Giles County Seismic Zone. Both zones produce small quakes relatively frequently, but ones as powerful as Tuesday’s event are uncommon.