Which makes the Navy-induced 3.9 explosion test far more pointed...
According to the USGS, The Navy explosion caused a 3.9 at 0.0 km depth and 170 km ENE of Ponce Inlet, Florida...which in turn is about 260 miles north of Surfside, Florida.
Interestingly, there have been several "Experimental" (i.e. "Navy") earthquakes in nearly that same spot in the ocean, 5 in 2016 of nearly the same magnitude.