Here's a news story from NJ, dated Dec. 10, 2011, about people feeling what they believed to be an earthquake, but nothing registered on the equipment. One of the possibilities for the shaking: http://www.nj.com/news/index.ssf/2011/1 ... ng_ea.html
A spokesman for the National Weather Service said its unlikely that even severe thunderstorms could make the ground feel as through it’s shaking.
Fighter jets used in drills near Virginia and North Carolina have caused sonic booms — the noise and vibration associated with traveling faster than the speed of sound — which can be mistaken for earthquakes, Bellini said.
Trust me... military aircraft and sonic booms that knock items off your shelves are part of NJ's charm.