Was this another frostquake? It seems not. A quake shook Ocean City, Maryland Thursday around noon. Mysterious ‘Boom’ Rattles Maryland | Maryland Earthquake | LiveScience.
It was also heard in Annapolis. But after local construction and blasting were ruled out (and no military testing admission was forthcoming), people suspected an earthquake or a frost quake. The geologic survey folks think no…
Richard Ortt Jr., director of the Maryland Geological Survey, said the seismic waves from the event spread at a rate too fast to be either an earthquake or a frost quake, a rare cold-weather phenomenon that has repeatedly popped up across the Northeast and Midwest during this extraordinarily frigid winter.
Instead, he said, the cause probably came from above ground.
“There’s many things that humans could have done to shake the ground,” Ortt said. “With the cold weather and high barometric pressure, any wave in the atmosphere would reach the ground relatively well.”
Eventually, the official cause seemed to be a sonic boom.
Late in the day, the Navy owned up to scheduling two supersonic flights off the Atlantic coast Thursday from its test flight facility at Patuxent Naval Air Station in Southern Maryland. But base spokeswoman Connie Hempel said the Navy isn’t taking responsibility and she would not know until Friday when the flights, part of “routine testing and training”, might have blasted by Ocean City.
That explanation satisfied the Maryland Geological Survey.
“At this time, we are confident that the supersonic flights were the cause of the felt reports,” Ortt said in an e-mail about 6 p.m.
But it didn’t satisfy those who were nervous about another quake or had heard sonic booms before that did not sound like this. Of course, weather could have played in as a factor since the atmosphere can reflect sound waves. Take a look at the seismograph. It does not look like an earthquake (the green ink trace) but you can also see other small disturbances. These things happen and are only noticed in certain circumstances.