Interesting, would be what was there, in that area, to have resulted in the recep. being there.
If the power for that recep. originates from the underfloor area, as if it had originally been power for an elec. wall heater, abandon it and "J" box to the floor joist and continue from there with either romex or flex. If it originates in the attic then either raise it to counter height and install a GFCI, or raise it to 15-1/2"
above the finished floor and turn it 180 degrees to make it accessible from the opposing wall.