Gamma-ray spectrometer measurement of /sup 238/U//sup 235/U in uranium ore from a natural reactor at Oklo, Gabon

Journal Article · Wed Dec 31 23:00:00 EST 1975 · J. Res. U.S. Geol. Surv.; (United States)

OSTI ID:7321848

Moxham, R M

A sample from the Oklo deposit containing about 0.51 atom percent /sup 235/U (by mass spectrometer) was analyzed by a gamma-ray spectrometer system, using a high-purity planar germanium detector. The /sup 238/U was determined from its daughter's (/sup 234/Th) 63.3 keV photopeak; the /sup 235/U was determined from its 143.8 and 163.4 keV photopeaks. The ratios of these photopeaks were compared with that from a standard having normal uranium isotopic content; the resulting calculations give a /sup 235/U abundance of 0.54 atom percent in the Oklo sample. The gamma-ray spectrum also contains lines from five other isotopes in the uranium series, which indicate the Oklo sample to be at or near secular equilibrium, as the time elapsed since the nuclear reaction ended was sufficient to permit the daughters to achieve equilibrium.

• OSTI ID: 7321848
• Journal Information: J. Res. U.S. Geol. Surv.; (United States), Journal Name: J. Res. U.S. Geol. Surv.; (United States) Vol. 4:5; ISSN JRGSA
• Country of Publication: United States
• Language: English

Related Subjects

050100* -- Nuclear Fuels-- Reserves
Exploration
& Mining
11 NUCLEAR FUEL CYCLE AND FUEL MATERIALS
37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CHEMISTRY
400103 -- Radiometric & Radiochemical Procedures-- (-1987)
ACTINIDE ISOTOPES
ACTINIDE NUCLEI
AFRICA
ALPHA DECAY RADIOISOTOPES
EVEN-EVEN NUCLEI
EVEN-ODD NUCLEI
FISSION
GABON
GAMMA SPECTRA
GAMMA SPECTROSCOPY
GEOLOGIC DEPOSITS
HEAVY NUCLEI
ISOMERIC TRANSITION ISOTOPES
ISOTOPE RATIO
ISOTOPES
MINUTES LIVING RADIOISOTOPES
NATURAL OCCURRENCE
NUCLEAR REACTIONS
NUCLEI
OKLO PHENOMENON
ORES
RADIOISOTOPES
RESOURCES
SPECTRA
SPECTROSCOPY
SPONTANEOUS FISSION
URANIUM 235
URANIUM 238
URANIUM DEPOSITS
URANIUM ISOTOPES
URANIUM ORES
X-RAY SPECTRA
YEARS LIVING RADIOISOTOPES