[meteorite-list] Source of Mystery Booms in North Carolina Likely to Remain Unknown

From: Ron Baalke <baalke_at_meteoritecentral.com>
Date: Mon Mar 21 13:24:55 2005
Message-ID: <200503091915.j29JFng04196_at_zagami.jpl.nasa.gov>

http://www.journalnow.com/servlet/Satellite?pagename=WSJ%2FMGArticle%2FWSJ_BasicArticle&c=MGArticle&cid=1031781442169&path=!localnews&s=1037645509099

Source of mystery booms likely to remain unknown

'Quiet' N.C. has no seismic-detection network

By Paul Garber
JOURNAL REPORTER (North Carolina)
March 8, 2005

The mysterious booms that rocked much of downtown Saturday night may
remain forever a mystery.

About 8:20 p.m., 911 dispatchers started getting a wave of calls
reporting the booms, said Shawn Cline, the hazardous-materials
coordinator for the Winston-Salem/Forsyth County Office of Emergency
Management. The calls covered an area of downtown between Glade and
Cherry streets, from Brookstown Avenue to the south and West 24th Street
to the north, he said.

Cline said that he spent most of yesterday looking at whether a small
earthquake or sonic boom might have caused the noise, but by the end of
the day he didn't have a solid answer.

There may not be enough earthquake-measuring equipment in the area to
determine whether a small earthquake occurred, said Tyler Clark, the
chief geologist for the N.C. Geological Survey.

"This is likely to go down in the history books as a mystery," Clark said.

Saturday's booms were about the 10th such report he has had from the
Winston-Salem area in the past five years, Clark said.

"These are not anything new," he said. "They've happened to our state
for a long time."

There are more active fault lines in the states that border North
Carolina then there are inside the state, he said.

"In North Carolina, we sit in the quiet zone," he said. Because of that,
there is not a network of seismic equipment to track local earthquakes.
It would be too expensive to track activity that almost never causes
death or destruction here, he said.

It's also possible that the noise was a sonic boom, which is more likely
to make the kind of explosive sound reported than an earthquake, Clark said.

But a sonic boom could not have come from a plane leaving or landing at
Smith Reynolds Airport because the plane would be going too slow, said
Dave Short, the air traffic manager at the airport.

Sonic booms occur when an airplane goes faster than the speed of sound.

Smith Reynolds air-traffic controllers do not track anything above its
air space of 12,000 feet, Short said.

City public utilities officials considered the possibility that a
methane explosion in a nearby sewer could have caused the booms but have
ruled out that possibility.

"If an explosion had happened, there's got to be a release of pressure
somewhere," said Ron Hargrove, the deputy director for the City-County
Utilities Division. There have been no such reports, which would include
such things as blown manhole covers or bubbles in toilet water.

Loud noises and vibrations that struck the Konnoak Hills neighborhood in
1994 turned out to be small earthquakes, the largest of which measured
1.7 on the Richter scale.
Received on Wed 09 Mar 2005 02:15:49 PM PST