... Science Frontiers ONLINE No. 121: Jan-Feb 1999 Issue Contents Other pages Home Page Science Frontiers Online All Issues This Issue Sourcebook Project Sourcebook Subjects Oklo: An Unappreciated Cosmic Phenomenon In 1972, French scientists discovered that several natural concentrations of uranium ore had become critical and flared up some 2 billion years ago at Oklo, Gabon. The concentration and configuration of the natural uranium and surrounding materials at that time had been just right to sustain fission. In fact, the analysis of the nuclear waste in the burned rocks demonstrated that plutonium had also been created. This implies that natural breeder reactors are also possible, raising the possibility of hitherto unappreciated, long-lived heat sources deep in the earth, in the other planets, and inside some of the stars. Don't worry ... the Oklo phenomenon might occur today on the earth's surface. The concentration of fissionable U-235 has fallen considerably in the last 2 billion years due to its radioactive decay. But, deep inside the earth and other astronomical bodies, nuclear criticality might still be possible due to different pressures, densities, etc. In a stimulating and generally overlooked paper in Eos, J.M . Herndon proffers four important natural phenomena that may involve natural fission reactors. Geomagnetic reversals . In the deep earth, where pressures and densities are high, natural nuclear reactors may generate intermittent bursts of heat -- just as they did at Oklo -- and thereby cause the earth's dynamo to falter and reverse. Planetary heating . Jupiter, Saturn, and Neptune emit much more energy than they ...

... pages Home Page Science Frontiers Online All Issues This Issue Sourcebook Project Sourcebook Subjects Precambrian nuclear reactors!On December 2, 1942, at Stagg Field, in Chicago, the first human-built nuclear reactor went critical. This feat has long been hailed as a triumph of the human intellect. Nature, though, had already beat E. Fermi and his colleagues by 2 billion years. For at Oklo and Bangombe, in the African Republic of Gabon, one finds the "ashes" where some 17 natural nuclear reactors cooked away for hundreds of thousands of years. Operating at temperatures as high as 360 C, they generated about 17,800 megawatt-years of energy. The Gabon reactors were discovered in 1972 when the French found that uranium ore from Gabon contained anomalously low concentrations of the ... . The half life of 235U is only about 700 million years. (Nagy, Bartholomew; "Precambrian Nuclear Reactors at Oklo," Geotimes , 38: 18, May 1993. Also: Nagy, Bartholomew, et al; "Role of Organic Matter in the Proterozoic Oklo Natural Fission Reactors, Gabon, Africa," Geology , 21:655, 1993.) Reference. The Oklo Phenomenon is covered in greater detail in ESP13 in the catalog: Anomalies in Geology. To order visit here . From Science Frontiers #94, JUL-AUG 1994 . 1994-2000 William R. Corliss ...

... Next Issue Sourcebook Project Sourcebook Subjects Contents Archaeology Two Remarkable Inscribed Stones Astronomy Thou Canst Not Stir A Flower, Without Troubling of A Star Natural Laser Beacons A Mysterious Object Biology Subtle is the Virus An Ocean Full of Viruses An Even Larger Ocean of Life Spores Still Viable After 7,000 Years Animals As Nutrient Carriers Geology Terranes Continue to Pile Up Grand Canyon Shamed Again When the Earth Shifted Gears The Oklo Phenomenon and Evolution Earth's Magnetic Field Jerks Osmium Isotopes Support Meteoric Impact Geophysics Incredible Phosphorescent Display on the China Sea Ball Lightning Splits and Recombines Inside Soviet Airliner Booms Startle Arkansas Psychology Mental Deflection of Cascading Spheres What Makes A Calculating Prodigy? False Pregnancies in Males Unclassified The 'Great Silence'; Or Why Aren't Aliens Landing on the White House Lawn? ...