During the 1950s geophysicists began to consider the possibility that nuclear fission might occurs naturally. Then, in 1972 a natural nuclear fission reactor was discovered at the Oklo uranium mine in the West African state of Gabon.
Natural nuclear fission reactor
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.
Oklo is the only known location for this in the world and consists of 16 sites at which self-sustaining nuclear fission reactions took place approximately 1.7 billion years ago, and ran for a few hundred thousand years, averaging 100 kW of power output during that time.
Mechanism of the reactors
The natural nuclear reactor formed when a uranium-rich mineral deposit became inundated with groundwater that acted as a neutron moderator, and a nuclear chain reaction took place. The heat generated from the nuclear fission caused the groundwater to boil away, which slowed or stopped the reaction. After cooling of the mineral deposit, the water returned and the reaction started again. These fission reactions were sustained for hundreds of thousands of years, until a chain reaction could no longer be supported.
Nuclear fission reactors as energy sources for the giant outer planets.
Herndon, J. M. (1992)
Naturwissenschaften 79, 7-14
In the following year J. Marvin Herndon presented evidence for the existence of uranium and thorium in the Earth’s core which could act as a naturally occurring nuclear fission breeder reactor that powers the Earth’s geomagnetic field.
Feasibility of a nuclear fission reactor at the center of
the Earth as the energy source for the geomagnetic field
Herndon, J. M. (1993)
J. Geomag. Geoelectr. 45, 423-437.
In 2001 Daniel F. Hollenbach and J. Marvin Herndon demonstrated [from numerical simulations made at Oak Ridge National Laboratory] that a deep Earth nuclear fission reactor will produce both light-helium [3He] and heavy-helium [4He] within the range of values observed from deep mantle sources.
Deep-earth reactor: nuclear fission, helium, and the geomagnetic field.
Hollenbach, D. F. & Herndon, J. M (2001)
Proc. Nat. Acad. Sci. USA 98, 11085-11090.
In 2003 J. Marvin Herndon demonstrated [from more detailed numerical simulations made at Oak Ridge National Laboratory] that a deep-Earth nuclear fission reactor will produce sufficient helium with precisely the range of ratios as observed from deep-source oceanic basalt lavas. The simulations indicate that the ratio of 3He to 4He increases over the lifetime of the deep-Earth nuclear fission reactor.
The high ratios observed in Icelandic and Hawaiian basalts suggest that the end of the deep-Earth nuclear fission reactor lifetime is approaching and it is presumed that the Earth’s geomagnetic field will begin its final collapse.
Nuclear georeactor origin of oceanic basalt 3He/4He, evidence, and implications.
Herndon, J. M. (2003)
Proc. Nat. Acad. Sci. USA 100, 3047-3050.
In 2011 it was reported that the measurement of the flux of antineutrinos emanating from deep within the Earth do not rule out the possibility of a deep-Earth nuclear fission reactor.
Interestingly, the geophysicists place an upper limit on the heat produced by a deep-Earth nuclear fission reactor of between 3 TW and 5 TW.
Unfortunately, this only adds credence to J. Marvin Herndon’s observations [and simulations] that indicate the end of the deep-Earth nuclear fission reactor lifetime is approaching.
Physics World – 19 July 2011
Radioactive decay accounts for half of Earth’s heat
About 50% of the heat given off by the Earth is generated by the radioactive decay of elements such as uranium and thorium, and their decay products. That is the conclusion of an international team of physicists that has used the KamLAND detector in Japan to measure the flux of antineutrinos emanating from deep within the Earth. The result, which agrees with previous calculations of the radioactive heating, should help physicists to improve models of how heat is generated in the Earth.
Geophysicists believe that heat flows from Earth’s interior into space at a rate of about 44 × 1012 W (TW). What is not clear, however, is how much of this heat is primordial – left over from the formation of the Earth – and how much is generated by radioactive decay.
One possibility that has been mooted in the past is that a natural nuclear reactor exists deep within the Earth and produces heat via a fission chain reaction. Data from KamLAND and Borexino do not rule out the possibility of such an underground reactor but place upper limits on how much heat could be produced by the reactor deep, if it exists. KamLAND sets this limit at about 5 TW, while Borexino puts it at about 3 TW.
More worryingly, Alfred de Grazia and Earl R Milton [1984 – Solaria Binaria] noted that the Earth’s magnetic field has been decaying “over the past few millennia” with a “half-life of about 1,400 years”.
Solaria Binaria – Chapter 8 – The Earth’s Physical and Magnetic History
Alfred de Grazia and Earl R Milton – 1984
Therefore, we can only speculate as to whether the Earth is experiencing a temporarily shutdown of the Earth’s nuclear reactor or the end of its natural lifetime.
Science About the True Nature of Earth and Universe
J. Marvin Herndon
Title: Maverick’s Earth and Universe
Author: Marvin J. Herndon
Hardcover: 276 pages
Publisher: Trafford Publishing (9 April 2008)