Abstract
The Oklo natural reactor, Gabon, permits study of fission-produced elemental behavior in a natural geologic environment. The uranium ore that sustained fission reactions formed about 2 billion years before present (BYBP), and the reactor was operative for about 5 × 105 yrs between about 1.95 to 2 BYBP. The many tons of fission products can, for the most part, be studied for their abundance and distribution today. Since reactor shutdown, many fissiogenic elements have not migrated from host pitchblende, and several others have migrated only a few tens of meters from the reactor ore. Only Xe and Kr have apparently been largely removed from the reactor zones. An element by element assessment of the Oklo rocks' ability to retain the fission products, and actinides and radiogenic Pb and Bi as well, leads to the conclusion that no widespread migration of the elements occurred. This suggests that rocks with more favorable geologic characteristics are indeed well suited for consideration for the storage of radioactive waste.
This is a preview of subscription content, log in via an institution to check access.
Similar content being viewed by others
References Cited
Allard, B., Torstenfelt, B., Andersson, K., and Rydberg, J., 1980, Possible retention of iodine in the ground, in Northrup, C. J., ed., Sci. Basis for Nuc. Wste. Mngmnt. II, New York, Plenum Press, p. 673–680.
Barton, P. D., and Skinner, B. J., 1979, Sulfide mineral stabilities: in Barnes, H. L., ed., Geochemistry of Hydrothermal Ore Deposits, 2nd Ed.: New York, Wiley-Interscience, p. 278–403.
Bonhomme, M., Leclerc, J., and Weber, F., 1978, Etude radiochronologique complémentaire de la série du Francevillien et de son environment: in IAEA p. 19–24.
Brookins, D. G., 1978a, Eh-pH diagrams for elements from Z=40 to Z=52: application to the Oklo natural reactor: Chem. Geol., v. 23, p. 324–342.
Brookins, D. G., 1978b, Retention of transuranic and actinide elements and bismuth at the Oklo natural reactor, Gabon: Chem. Geol., v. 23, p. 309–323.
Brookins, D. G., 1978c, Application of Eh-pH diagrams to problems of retention and/or migration of fissiogenic elements at Oklo: in IAEA, p. 243–265.
Brookins, D. G., 1980, Syngenetic model for some early Proterozoic uranium deposits: evidence from Oklo: Int. Atomic Energy Agency Sym. on the Pine Creek Geosyncline, p. 709–719.
Brookins, D. G., 1981, Alkali and alkaline earth studies at Oklo: in Moore, J. G., ed., Sci. Basis Nuc. Wste. Mngmt. III: New York, Plenum Press, p. 275–282.
Brookins, D. G., Lee, M. J., Mukhopadhyay, B., and Bolivar, S. L., 1976, Search for fission-produced Rb, Sr, Cs and Ba at Oklo: in IAEA, p. 401–414.
Christensen, A. B., Del Debbio, J. A., Knecht, J. D., and Tanner, J. E., 1981, in Moore, J. G., ed., Loading and leachage of krypton immobilized in zeolites and glass: Basis Nuclear Wste. Mngmnt. III: New York, Plenum Press, p. 267–274.
DeLaeter, J. R., Rosman, J. K. R., and Smith, C. L., 1980, The Oklo natural reactor: cumulative fission yields and retentivity of the symmetric mass region fission products: Earth Plan. Sci. Lttrs., v. 50, p. 238–246.
Drozd, R. J., Hohenberg, C. M., and Morgan, C. J., 1974, Heavy rare gases from Rabbit Lake (Canada) and the Oklo mine (Gabon): natural spontaneous chain reactions in old uranium deposits: Earth Plan. Sci. Lttrs., v. 23, p. 28–37.
Fréjacques, C., Blain, C., Devilliers, C., Hagemann, R., and Ruffenbach, J. C., 1976, Conclusions tirées de l'étude de la migration des produits de fission: in IAEA, p. 509–526.
Gancarz, A. J., 1978, U-Pb age (2.05 × 109 years) of the Oklo uranium deposit: in IAEA, p. 513–520.
Gancarz, A. J., Cowan, G. A., Curtis, D. H., and Maeck, W. L., 1980, Tc-99, Ru and Pb migration around the Oklo natural fission reactors: in Northrup, C. J., ed., Sci. Basis Nuc. Wste. Mngmnt. II: New York, Plenum Press, p. 601–608.
Gauthier-Lafaye, F., 1978, Suivi géologique de l'exploitation des réacteurs naturels d'Oklo: in IAEA, p. 75–130.
Geoffroy, J., 1976, Etude microscopique des minerais uraniféres d'Oklo: in IAEA, p. 133–150.
IAEA, 1976, The Oklo phenomenon: Inter. Atomic Energy Agency Sym. 204, 646 p.
IAEA, 1978, Natural fission reactors: Inter. Atomic Energy Agency Tech. Pub. 119, 754 p.
McLennan, S. M., and Taylor, S. R., 1979, Rare earth elements mobility associated with uranium mineralization: Nature, v. 282, p. 247–249.
Naudet, R., 1978, Les réacteurs d'Oklo: cinq ans d'exploration du site: in IAEA, p. 3–18.
Weber, F., 1969, Une série precambrienne du Gabon: Le Francevillien, Sédimenrologie, géochimie, relations avec les gites minéraux associés: Ph.D. dissertation, Univ. Strasbourg, 325 p.
Weber, F., and Bonhomme, M., 1976, Données radiochronologiques nouvelles sur le Francevillien et son environment: in IAEA, p. 17–36.
Author information
Authors and Affiliations
Rights and permissions
About this article
Cite this article
Brookins, D.G. Migration and retention of elements at the Oklo natural reactor. Geo 4, 201–208 (1982). https://doi.org/10.1007/BF02380513
Issue Date:
DOI: https://doi.org/10.1007/BF02380513