Fixation of radionuclides in the 238U decay series in the vicinity of mineralized zones: 1. The Austatom Uranium Prospect, Northern Territory, Australia
Fixation of radionuclides in the 238U decay series in the vicinity of mineralized zones: 1. The Austatom Uranium Prospect, Northern Territory, Australia
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矿化带附近 238U 衰变系列中放射性核素的固定: 1. 澳大利亚北领地 Austatom 铀矿勘探区
DOI:
10.1016/0016-7037(83)90263-6
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发表时间:
1983
影响因子:
5
通讯作者:
P. Shirvington
中科院分区:
文献类型:
--
作者:
P. Shirvington
The minimum age of a zone of secondary uranium mineralization, located at the Austatom Prospect in the Alligator Rivers region of Australia, is estimated to be 3.6 × 105y. This is derived from a geochronological model based on retarded leaching of234U with respect to238U and on ratios within the ore of these members of the238U decay series. Although kaolinite is a dominant mineral in the weathered schist-host-rocks, retarded dissolution of234U occurs only in the presence of the clay minerals illite and montmorillonite. In their absence the reverse occurs. A model is proposed to explain the results. Ratios of230Th to238U indicate that the mineralization has probably remained stationary within the weathered schist for at least 1 to 2 × 105y. Future use of clay minerals as buffers in radioactive waste repositories is supported by the excellent long-term retention obtained for oxidized uranium, probably due in part to isomorphic substitution into the clay crystal lattice.