- Location
- U.S.
I don't know. The thing is that its going to spread exponentially. The process won't strictly be slow - as soon as you impart energy on the ice great enough to vaporize it, its instantly hot. Its actually a fairly close analogue of how high explosives detonate; a small region is triggered, which creates conditions on the boundary that are strong enough to detonate the surrounding material. That material likewise can detonate adjacent material, and so it spreads.I agree it would be substantial, but it's now slow enough that I don't think we're looking at a nuke-equivalent explosion. Something on the order of a few dozen tons of TNT seems more reasonable.
So long as the reaction is fast enough to proceed through all the ice without too much of it exiting the AoE or destroying the rune, I suspect it would be full strength. And it would tend to occur from the outside-in, so the forces involved would tend to force the ice inwards, not outwards. That doesn't mean it'll just implode neatly like the core of a nuke; that takes a lot of precision. But it could be enough that most of it remains in the AoE.