>to create a 2.2 EQ
Anon, this is incorrect. Yield is the key word. The energy released from a 2.2 EQ is equivalent to the yield ~ 3 Tons of TNT. Yield = the amount obtained from a process or reaction relative to the theoretical maximum amount obtainable.
You are looking at output and equivalents, not what it takes to set off an earthquake. It would be very hard to determine what would set off an earthquake because of the many variables involved. It would be unique to each location, distance to fault lines, depth, and about a million other things.