A worker at a nuclear fuel processing plant noticed something suspicious in a routine analysis of uranium obtained from a normal mineral source from Africa. As is the case with all natural uranium, the material under study contained three isotopos- ie three forms with different atomic masses: uranium 238, the most abundant variety; uranium 234, the rarest; and uranium 235, the isotope that is coveted because it can sustain a nuclear chain reaction. For weeks, specialists at the French Atomic Energy Commission (CEA) remained perplexed
Elsewhere in the earth’s crust, on the moon and even in meteorites, we can find uranium 235 atoms that makes up only 0.720 percent of the total. But in the samples that were analyzed, which came from the Oklo deposit in Gabon, a former French colony in West Africa, the uranium 235 constituted only 0.717 percent. That small difference was enough to alert French scientists that there was something very strange going on with the minerals. These small details led to further investigations which showed that least a part of the mine was well below the normal amount of uranium 235: some 200 kilograms appeared to have been extracted in the distant past, today, that amount is enough to make half a dozen nuclear bombs. Soon, researchers and scientists from all over the world gathered in Gabon to explore what was going on with the Uranium from Oklo.
What was fund in Oklo surprised everyone gathered there, the site where the uranium originated from is actually an advanced subterranean nuclear reactor that goes well beyond the capabilities of our present scientific knowledge. Researchers believe that this ancient nuclear reactor is around 1.8 billion years old and operated for at least 500,000 years in the distant past. Scientists performed several other investigation at the uranium mine and the results were made public at a conference of the International Atomic Energy Agency. According to News agencies from Africa, researchers had found traces of fission products and fuel wastes at various locations within the mine area.
Incredibly, compared with this huge nuclear reactor, our modern-day nuclear reactors are really not comparable both in design and functionality. According to studies, this ancient nuclear reactor was several kilometers long. Interestingly, for a large nuclear reactor like this, thermal impact towards the environment was limited to just 40 meters on all sides. What researchers found even more astonishing, are the radioactive wastes that have still not moved outside the limits of the site as they are still held in place tanks to the geology of the area.
For more: http://www.disclose.tv/news/researchers_discover_a_2_billion_year_old_nuclear_reactor_in_africa/118482