In a remarkable discovery, French scientists have uncovered a natural nuclear reactor in Gabon, Africa, which operated approximately 2 billion years ago. This finding emerged during their analysis of uranium deposits in the region.
Researchers at the Pierrelatte nuclear facility examined uranium samples from Oklo and found an anomalous concentration of the isotope U-235, crucial for nuclear reactions. Instead of the expected 0.72%, the U-235 level was measured at 0.717%. This deviation raised questions, as such changes are exceedingly rare.
Further investigations revealed even more significant anomalies, with some samples showing U-235 concentrations as low as 0.4%. The scientists concluded that natural fission reactions occurred at this site.
During that era, Earth’s conditions were markedly different. The U-235 content was higher, and the uranium deposits at Oklo were submerged underwater. The water acted as a neutron moderator, similar to the function in contemporary nuclear reactors.
As the water heated from the reactions, it evaporated, temporarily halting the process. Upon cooling, the system would restart, cycling through this process for thousands of years until the uranium was depleted. This ancient natural reactor offers valuable insights into sustainable energy solutions, potentially guiding modern nuclear technology and safety protocols.