SC has a history of earthquakes, and we have even had a big one in Charleston that leveled half of the city. http://earthquake.usgs.gov/earthquakes/states/events/1886_09_01.php You can still see many remnants of the earthquake, while walking through the peninsula. Many old building and homes have large screw-like structures sticking out of the outer walls. These are what they used to press the fractured walls back together following the quake. Crazy stuff to think about. You have to remember, the Earth beneath us is always in motion. I was in Richmond during that larger quake that hit a couple years ago. Pretty strange feeling, when you are on the 4th floor of a semi-tall building. That swaying feel just isn't comforting.
The OCMD thing was a "Sonic Boom" confirmed by the military.... Sorry I was late for the party but my dad posted that last week.
Was another quake I guess early this morning in the North Atlantic. I guess it was too deep to cause a Tsunami. Maybe also not strong enough. http://www.mynews13.com/content/news/cfnews13/news/article.html/content/news/articles/cfn/2014/2/18/earthquake_in_north_.html
I still don't believe it was any type of sonic sound wave. Remember that one in August 2011? I was in the same location and this one was the same strength. Definitely came from the ground the way my house shook, not from the sky. We've heard all the normal sonic booms and whatnot. If it was from the sky it was not done in clear sight. I think it has to do with fracking or underground explosive device testing.