NS  Vol.4 No.11 A , November 2012
Origin of enriched uranium contained in Japanese atmospheric deposits
Abstract: The chemical compositions of atmospheric deposits collected in Fukuoka, Japan, in 1964 and 2000, which are known to have high 235U/238U uranium isotope ratio were determined. High uranium contents relative to that of continental crust were observed for the deposition samples in 1964 together with the high 235U/238U ratios, which indicated that the origin of uranium is fallout materials due to the large-scale 1961- 1962 nuclear explosions conducted by US and former USSR. The deposits in 2000 were mainly composed of dusts from the East Asia. This suggested that uranium with a high 235U/238U ratio in the deposits in 2000 has been transported as a component of mineral dust particles contaminated with nuclear debris from nuclear test sites from the East Asian deserts and arid regions by the prevailing wind.
Cite this paper: Kikawada, Y. , Oda, K. , Nomura, M. , Honda, T. , Oi, T. , Hirose, K. and Igarashi, Y. (2012) Origin of enriched uranium contained in Japanese atmospheric deposits. Natural Science, 4, 936-942. doi: 10.4236/ns.2012.431122.

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