Release, Migration, Sorption and (re)precipitation of U During a Granite Alteration under Oxidizing Conditions

A study of release, migration, sorption and (re)precipitation of U during alteration under oxidizing conditions were carried out in U minerals from a granite and hydrothermal quartz veins.U-bearing minerals can be related with precipitation from faults orsolubilizationand remobilizationminerals by meteoric waters. The hot meteoric fluids dissolved (the remaining) uraninite, coffinite, thorite, etc. in the granite and apatite, monazite, xenotime in the quartz veins. These fluids were responsible for the growth of U-bearing minerals in the hydrothermal quartz veins, by adsorptionor by precipitation. The neoformation associated to weathering could be a mechanism of U concentration.