Authorities seeking the source of big boom heard in local communities

Dec. 2—BLUEFIELD — What caused a loud boom that startled residents and shook houses across much of Mercer County and neighboring Tazewell County, Va. Friday remained a mystery after firefighters sought out a source and did not locate one.

The boom, which occurred around 9:30 a.m., was heard and felt in Bluefield, Montcalm, Bluewell and the Lorton Lick Road area and Prosperity School Road area as well as locations as far away as Falls Mills,Va., and Bluefield, Va.

Most people who called 911 and first responders about the boom compared it to an explosion or thunder, said Director Keith Gunnoe at the Mercer County Office of Emergency Management.

Gunnoe said the first call involved an individual who reported that their house shook, and that they heard what they thought was an explosion on Old Bramwell Road.

"It sounded like thunder and their houses shook," Gunnoe said.

An earthquake, a mine explosion, the collapse of an underground mining tunnel or a supersonic aircraft's sonic boom were suggested as possible sources. Fire departments searched the area to see if there had been any explosions, but nothing was discovered.

"It was unfounded pretty much," Gunnoe said.

Gunnoe said he monitored websites of government agencies like the United States Geological Survey (USGS), but no earthquakes were reported where the loud boom was experienced, so he was "pretty positive" that an earthquake didn't make that noise. A professor at Virginia Tech in Blacksburg, Va. agreed.

"It wasn't an earthquake," said Professor Martin Chapman with the Department of Geosciences at Virginia Tech. "I don't know what it was. We didn't record it in Blacksburg."

"Our seismographs in Blacksburg didn't pick up any disturbance there," he stated about the Mercer County area.

Sometimes supersonic aircraft generate sonic booms over the region and occasionally a celestial object like a meteor entering the atmosphere could create such a loud sound, Martin said, adding a meteor was unlikely since those events usually impact a large area. He had not heard any other reports of loud booms in the region.

Martin was asked whether the collapse of an underground mine or a cave could have caused the loud boom, but such an event would have been detected by Virginia Tech's equipment, he said.

"We've got a lot of mysteries around here," Martin said.

— Contact Greg Jordan at gjordan@bdtonline.com

Contact Greg Jordan at gjordan@bdtonline.com