The Delaware Emergency Management Agency told the Dover Post that there were no reports of damage or injuries. I correctly deduced it must have been an earthquake!”[ Magnitude 4.1 earthquake near Dover, Del., rattles Mid-Atlantic ]Closer to the epicenter, the earthquake was more dramatic. The hazard maps produced by the USGS do not show Delaware having a significant seismic hazard. The East Coast has a limited history of major earthquakes, but experts say that citizens should not assume they are free of seismic hazard. Indeed, New York City is considered highly vulnerable over the long term because so many masonry structures lack the kind of reinforced steel that is required in places with more of a known earthquake risk.

Source: Washington Post December 01, 2017 00:13 UTC