Lysergic, cool find with the natural reactor page

Thanks!
I have read about them, but not seen any photos like that.
Xaos, I understand where you are going about the natural reactors going supercritical, however it has never been found to be the case, and honestly I
dont think that it is possible in nature. Although there may well be enough naturally occurring radioactives to start up a limited chain reaction, it
would very likely NOT be enough in terms of amount or in terms of purity to carry on a sustained and uncontrolled chain reaction (the possible
exception to this in nature may be in the inner mantle and core, where some rules tend to bend, but nto in the crust). Also, there would be too much
intervening material acting as a moderator to allow a runaway chain reaction.
As far as evidence for far past nuclear events, I am drawn to stories of the Vitrified Forts of the Scottish Highlands.
The rock these "forts" are made out of is granite, but most all of them have been melted into a vitrious glass for 360 degrees around thier entire
circumfrence. I dont know how many of these forts there are, but I understand there to be dozens.
(Gryffen, any local info on these???)
I did read a report about these where an experiment was conducted. Representative granite from the area was surround by a complete bonfire built
around it, with the idea to find out how hard it would be to melt the rock. The calculations from this experiment showed that in order to create just
a handful of these "forts" (and there were dozens of them) it would require the consumption of every tree in Scotland.