By Terry Rogers
On Wednesday, November 30 at 4:47 PM, many residents of Milford felt the earth move when an earthquake with an estimated magnitude of 4.1 on the Richter scale occurred just east of Dover. Some reported feeling as if they were off balance, others noticed windows rattling and items on shelves quivering as the earthquake rumbled through the area. According to John Belini, a geophysicist with United States Geographical Services, the agency that tracks and studies earthquakes, people south of Washington DC, New York City and the northwestern tip of Connecticut all felt the rumbling.
Immediately after the earthquake, social media filled with people in the area who felt it. Austin Stewart, from Houston, was in his dorm at Delaware State College and reported that the dorm was “shaking and the floor was wobbling.” Ivy Hinson said she was in Big Lots and they thought the building was going to cave in when the ground began to shake. Many others, however, said they did not feel the earthquake at all.
“That is very possible,” Mr. Belini said. “It all depends on the environment you are in. This was a relatively small quake so if you were in a loud restaurant or a construction area, you probably would not have noticed it. It may have sounded like loud wind or a truck rumbling by.” In fact, Kate David posted on social media that she was unaware it was an earthquake, believing it was just an exceptionally large truck going past her home.
Initially, USGS reported that the earthquake was a magnitude 5.1, but it was later lowered to a 4.1. He said that this is not uncommon as the scientists get more details and data regarding earthquakes. He said there have been no reports of damage, something else that is not unusual due to the size of the earthquake and where the epicenter was located.
The epicenter of the earthquake was six miles east-northeast of Dover in an area that Mr. Belini says appears to be wetlands not far from the Delaware Bay. He said there are farmlands surrounding the location which means there were no buildings to suffer serious damage. He said there are several faults below the surface of the Earth on the east coast and that this earthquake was caused by movement in one of the faults approximately 8.1 kilometers below the surface.
On August 23, 2011, many residents in the area felt an earthquake whose epicenter was five miles south-southwest of Mineral, Virginia. That earthquake was a 5.8 on the Richter scale and caused damage as far away as Washington DC.
USGS asks anyone who felt the earthquake to fill out a “Felt Report” on their website.