Northeastern US quakes are typically the result of post-glacial uplift. The land is still rising and stress builds up over time.

there's a good general description of seismicity in the region here:

https://earthquake.usgs.gov/earthquakes/eventpage/us7000ma74...

Likely Ramapo, but what do I know.

I didn't stay at a holiday in last night, but I can read maps and it does seem like this one landed on the Ramapo fault line.