Uranium granite well water

Radon gas is formed in the process of radioactive decay of uranium. The distribution of naturally occurring radon follows the distribution of uranium in geological formations. Elevated levels have been observed in certain granite-type minerals. Residences built in these areas have the potential for elevated indoor concentrations of radon from radon gas entering through cracks and crevices and from outgassing from well water. 

Chemical analyses and related information for some well waters from uranium deposits and two unmineralized granites (Aspo and Stripa,... 

Evolved granites may contain uranium and thorium in very high concentrations and hence may account for a large fraction of their total content in the crust. One difficulty is that they are open to water circulation in the near-surface environment, which leads to uranium depletion (Oversby, 1976 Jaupart et al., 1981 A. Forster and H.-J. Forster, 2000). These effects are well documented and have been demonstrated even in... 

This model for uranium mineralization associated with granites requires (1) a metalliferous Sn-U mildly alkaline type or transitional granite to rise to a level in the crust where it will create a thermal anomaly (2) adequate water of suitable chemistry for hydration and reduction of primary silicates (thus rocks of low metamorphic grade and more pelitic composition, particularly graphitic shales, will favour mineralization) and (3) a well-developed fracture system, particularly for low-temperature mineral deposition. 

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