Click here to read a Wikipedia article that Alan Kafka wrote on Earthquake Activity in the New York City Area. (Since it’s a wiki, others are of course revising and editing it.)
He also made extensive revisions to the Wikipedia article on the Ramapo Fault, a fault zone that has been argued to be the source of earthquakes in the New York City area. As described in the article, some seismologists have argued that the Ramapo fault has the potential to produce a major earthquake, but as can be seen in the figure below, earthquakes are scattered throughout the New York City area, with no particular concentration of activity along the Ramapo fault. Thus, my colleagues and I have argued that neither the Ramapo fault (nor any other known fault in this region) has been demonstrated to be any more active than any other parts of the greater New York City area.
Seismicity in the vicinity of New York City. Data are from the U.S. Geological Survey (Top, USGS) and the National Earthquake Information Center (Bottom, NEIC). In the top figure, closed red circles indicate 1924-2006 epicenters and open black circles indicate locations of the larger earthquakes that occurred in 1737, 1783 and 1884. Green lines indicate the trace of the Ramapo fault.