(November 13, 2013 at 7:42 pm)Chuck Wrote:(November 13, 2013 at 7:24 pm)Cthulhu Dreaming Wrote: That isn't fallout. What force is driving the contaminated material into the atmosphere from where it would fall out?
The roof collapse of the cavity compresses the air inside, which then erupts through breaches in the roof of the cavity, entraining the radioactive material from inside the cavity and expel them into the atmosphere.
I don't know what fraction of underground test cavities collapsed. But aerial photos of the Nevada test site certainly shows very large numbers of seriously fragmented collapse depressions over test cavities.
Could be. I'm not quite sure how to characterize that. My experience with this stuff is from my duties in the military, which included assisting in producing fallout predictions (direction, speed, area and casualties) from nuclear blasts. Charming stuff, that, as you can imagine.
As our models were intended for battlefield use, and were created partially using data obtained from actual historical tests (as well as a high degree of theory), that scenario is not one that I would know much about.
I don't doubt it would throw some material skyward, but I strongly suspect that due to the magnitude of forces involved, that the impact would be substantially less.
In any case, none of this has much bearing on the OP's point that we've detonated a frightening number of the damnable things, and on that point, I certainly can find no argument.
