In the ground level and underground nuclear explosions I’ve read about , none of them ever produced significant amounts of molten magma. They seem to produce (1) A fireball of very hot gas or plasma (2) A thin layer of glazing on the sides of the crater/ cavern left behind. Why is this? Would if be different if you dentonated a nuke in an already existing pool of magma? Maybe you could have an Apokolips-style Hell Pit, kept hot by setting off a nuke in it every few days.
What you call significant may be the problem. The molten rock (what little you’d find) is usually hardened by the time you would be able to “investigate” the scene though. IIRC Chernoble (sp?) still has a lava pool leftover from the meltdown and 3mile island had a small one that finally cooled.
Could you maintain a hot pool of molten rock… why would you want to?
I’m sure I’ve missed something but volcanic activity isn’t usually something you want to be around is it?
WAG here but from what I’ve read on the subject the area in which you would find a “pool” is too hot for lava to form. It is the radiation that remains which heats the rock and causes the melt down. Any matter in the actual explosion site is more or less vaporized and anything nearby is scattered to the four winds. Thus no significant “pools” would be found.
My WAG is that the duration of heating is too short to melt a large amount of rock. Most of the heat goes into vaporizing the top layer, which absorbs and carries away the heat. A thin layer below that may liquify, but there isn’t time for heat to permeate further down.
Imagine taking a huge lump of meat - say, a whole cow - and putting it on the hottest grill imaginable - perhaps a pool of moten steel - for just a few seconds. You don’t end up with a huge pile of medium rare steak. You end up with a lump of meat that’s completely burnt on the outside and still raw on the inside. Same thing.
I think ** scr4 ** is on to the right answer.
Here’s a link to a page on the Trinity test, and it mentions “trinitite”, which was fused soil left by the test.
I think the problem would be that most detonations low enough to involve a great deal of the ground would blast a pretty serious crater, and most airbursts would be too high to melt the ground. Apparently the Trinity test was just high enough to avoid doing either.
Cite?
TMI did not melt down. No way it made magma. I seriosly doubt Chenobyl did either.
My WAG is that the energy of a nuclear bomb is nothing compared to the thermal energy of molten lava comming out of a volcano.
Assuming heat capacy of 0.9 kJ/kg-K, melting point of 1000 C, initial temperature of 20C and heat of fusion as 40 kJ/kg, you need 922 kJ/kg of heat to make lava. 1 megaton is 4.2x10[sup]15[/sup] J, or 4.2x10[sup]12[/sup] kJ, so that’s enough energy to make about 4 million tons of lava, if all that energy is used to melt (but not vaporize) the ground. That’s comparable to what a major volcano can produce in a couple of hours (cite). (That’s also assuming I did it right, which may not be a good assumption at this hour.)
Lava is molten rock, molten rock is not lava. :rolleyes:
So are you going to tell us what the difference is?
without going to a cite…and I will but for now off the top of my head. The molten rock was the result of the extremely high temperatures due to the radiation and heat produced when the cooling failed at 3MI and Chernoble was an actual meltdown. The concrete structure and foundation as well as the blocks and bricks in the walls and floors are what melted down into a pool. At Chernoble the radiation was high enough to absorb down into the ground…but I will see if I can find a cite, be back soon. 
I haven’t found a really good cite that I want to post yet. There are plenty of them out there. It’s getting late and I’ll get back to you though. Meanwhile I did find this one. It doesn’t go into detail regarding the radioactive lava that still exists at Chernobyl and will for a long time. The shell that currently “houses” the plant is about to cave in and they are going to build a new one that is supposed to last for a hundred years. The radiation levels released into the atmosphere and the surrounding countryside were supposedly 1000 times greater than the atomic bombs at Hiroshima and Nagasaki.
And 3MI did get that hot for a little while. Hang on though, I’ve got plenty of cites but I know the people here. If GOD didn’t come down and say it to your face it doesn’t count.
There’s one in the Washington Post dated 2002 I could link. Is the Wash. Post okay?
BTW the “molten rock” is a mixture of the old fuel rods, melted with the concrete from the building and sand that was dumped on it in an attempt to cool off the site. This melted down into the ground through the base of the plant and is now a huge molten mass of radioactive “lava”.
I’m gonna hit the rack and check back in la manana…nite all.
I think you’re thinking of the 'Chernobyl ‘lava’" (Note second set of quotation marks), t-keela—this “lava” is actually the remains of the melted nuclear fuel from Chernobyl’s reactor #4 that “had apparently eaten through the concrete floor and oozed into the warren of rooms below, where it cooled and hardened.”
The stuff—which I seem to remember was nicknamed “Chernobilite”—has been solid for quite some time, now. (I’d guess since shortly after the meltdown.)
D’oh…Seven minutes too late. :smack:
Perhaps Ouryl was trying to explain the difference between magma and lava ?
No I’m still with ya Ranchoth had another thread to closeout…
You maybe right buddy. I didn’t say I was certain here. But since then I’ve read quite a bit on the subject and you are correct about the molten fuel rods. They melted through the concrete floor and parts of the surrounding walls and the tons of sand and lead that was dropped from helicopters. As far as it being hard…I know the cites I read claim the top layer to be hard but that was only the surface. They are gonna build another shell to cover the existing one because it’s already deteriorating from rust. Gonna use cement again IIRC. :smack: some folks don’t seem to ever learn do they
The NRC Report does not support the contention that there was melted rock produced by the melt down at TMI. Although half the core was melted, and a large number of the cladding vessels were breached, no rupture of the containment vessle was reported. Radiation leaks were all atributed to gass leaks from the cooling system, and possible difussion of the hydrogen bubble generated during the event.
Chynoble was a different story. Liquid Plutonium flowed out of the containment vessel, and melted it’s way through the floor into lower levels. It still didn’t quite reach China (California?) though.
Tris
Yep. I saw a documentary on it once; they got a marksman down there with a rifle to shoot some pieces off from the other side of the room, hoping the fragments would fly close enough so they could grab them for analysis.