that is a realy interissting thing, but i think that you would need a more complex script.
You would need to place a layer of cubes as ground.
whenever there is a detonation point, like say a bomb hits the ground,
you would run the script.
this script would need to calculate how deep this explosion would be, direction etc,
then with all that data collected, you would simply remove all cubes that are in the detonation globa and place new ones around that globe.
Ofc this sounds simpler than it is, as you would need alot of other things to calculate as, if here can be a cube or not. But basicly ^^ that is what i have on my mind.
What i would not recommend is, to make like 1 bazzilion cubes and then simply remove it, that would kill your FPS.