rs
Dagobah Resident
http://www.signonsandiego.com/news/metro/20060404-1102-bn04boom2.html
Yeah. That's it. It was mortars. What happened is that a whole bunch of sound waves from the mortars decided to hang around and build each other up, then move from Camp Pendleton to San Diego and form a (as in one) big boom.UNION-TRIBUNE BREAKING NEWS TEAM
11:02 a.m. April 4, 2006
SAN DIEGO – A big boom was heard around San Diego County Tuesday morning, but it was unclear what caused it.
The U.S. Geological Survey and CalTech said there was no seismic activity in the San Diego area.
“We are not showing any seismic activity in San Diego. So, it was something else. It wasn't an earthquake,” said Deborah Williams-Hedges, a spokeswoman for CalTech.
A microearthquake with a magnitude of 1.6 was reported at 8:53 a.m. but it was located near Ridgecrest, Calif., which is about 200 miles from San Diego.
A spokesman at Camp Pendleton in North County said they were doing routine artillery training Tuesday morning, but it was not known whether that was responsible for the rattling felt all over the region.
“I can't say we caused the boom, but I can say we are conducting training this morning with 81mm mortars,” said Marine Cpl. K.T. Tran. “The training started at 6 a.m. and it is going to end at midnight.”
Base officials say rumblings from the mortar training at times can be heard up to 50 miles away, depending on atmospheric conditions.
Whatever caused the boom had residents from all around the region calling emergency dispatchers at the county Sheriff's Department and San Diego Police Department shortly before 9 a.m.
“There was a boom and we don't know what it is,” said Lt. Jim Bolwerk, who works in the sheriff's communication center.
The boom caused windows to rattle in office buildings in Mission Valley and in Kearny Mesa as well as homes in Poway and Rancho Santa Fe. Residents reported the rattling lasting for several seconds.
A spokeswoman at Miramar Marine Corps Air Station said it wasn't caused by any activity or aircraft on the base.
“We have nothing on our flight line, nothing unusual going on,” said Lt. Victoria Jennings. “We felt it here, too.”
A spokeswoman at Vandenberg Air Force, which is north of Santa Barbara, said she didn't think their base was responsible, either.
“We didn't launch any rockets. I can find out if there is aircraft testing,” said Tech Sgt. Rebecca Danet.
Dennis Feltgen, a meteorologist for the National Oceanic and Atmospheric Administration in Silver Spring, Md., said he knew of no weather phenomenon in the San Diego region that could have caused the boom.
County emergency officials also were stumped.
“Speculation is it's a sonic boom or something along that line, but it is all speculation,” said Tom Amabile, a senior emergency services coordinator with the county Office of Emergency Services.