The Oklo Reactor is Located in the Oklo region of Gabon in Africa and consists of 16 uranium-rich sites where self-sustaining nuclear chain reactions took place billions of years ago.
A natural nuclear fission reactor is a uranium deposit where self-sustaining nuclear chain reactions have occurred. This can be examined by analysis of isotope ratios. The existence of this phenomenon was discovered in 1972 at Oklo in Gabon, Africa, by French physicist Francis Perrin.
The conditions under which a natural nuclear reactor could exist had been predicted in 1956 by Paul Kazuo Kuroda. The conditions found were very similar to what was predicted.
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