On November 29, 1783, at 10:50 p.m. (UTC−5), a Mfa 5.3 earthquake occurred in the U.S. state of New Jersey. It was the state's first recorded seismic event. It is estimated that the quake was the largest and strongest that the state has ever recorded. The earthquake caused intensity VII damage on the Mercalli intensity scale.

Location

The earthquake is thought to have originated from within the New Jersey Highlands of the Reading Prong, possibly on the 300 km long, 12 km wide Ramapo Fault zone, a structure formed during the Late Triassic during the break-up of Pangaea. The mainshock was part of a sequence that occurred over a span of several hours. A brief foreshock occurred at 9:00 PM on November 29 (02:00 UTC on November 30), and an aftershock five hours later was reported only in New York City and in Philadelphia, Pennsylvania. The main shaking was felt from New Hampshire to Pennsylvania. There are reports and recordings in diaries that suggest that the earthquake was felt in neighboring states.

Damage

The overall destruction of the quake was not very serious, only ranking as intensity VII damage on the Mercalli intensity scale. The physical damages include dishes thrown off the shelves, people waking up from the shaking, and multiple damaged chimneys. George Washington was visiting New York City at the time to mark the Evacuation Day departure of British forces, and was sleeping at Fraunces Tavern when the earthquake struck, but he was not woken by the tremors.

Reports

Reports show that the earthquake was felt in Philadelphia, New Haven, and Boston.

Diary reports

Diary entries regarding the earthquake were very brief.

Newspaper reports

Many Contemporary newspapers reported on the earthquake.