Uranium in granitic magmas: Part 2. Experimental determination of uranium solubility and fluid-melt partition coefficients in the uranium oxide-haplogranite-H2O-NaX (X = Cl, F) system at 770°C, 2 kbar

Magmatic and hydrothermal behavior of uranium in syntectonic leucogranites: The uranium mineralization associated with the Hercynian Guérande granite (Armorican Massif, France)

“…a surface-derived hydrothermal fluid) favors the transport of U (Dubessy et al, 1987). However, the solubility of U in reducing magmatic fluid exsolved from a peraluminous melt increases greatly if these fluids are enriched in chlorine (Peiffert et al, 1996). Therefore, we suggest that the first evolution trend (Fig.…”

“…Cuney, 2014), has not been directly observed in our samples but its presence has been reported by Ouddou (1984) in the northwestern part of the intrusion. In peraluminous magmas, uraninite typically crystallizes when bulk U contents reach around 10 ppm (Peiffert et al, 1996). Therefore, the maximum U content of 8 ppm observed in the studied Guérande samples does not seem to be representative of the initial value.…”

Estimation and mapping of uranium content of geological units in France

“…As a result of its large ionic radius and high valency, uranium is not incorporated into the structure of the main rock forming silicates, which results in its incompatible behavior in silicate magmas. Consequently, during partial melting and crystal fractionation, uranium is preferentially fractionated into silicate melts (Cuney, 1982;Peiffert et al, 1994Peiffert et al, , 1996. The most felsic melts producing granites and rhyolites, tend to be the most enriched in uranium.…”

Rôle des facteurs hydrodynamiques dans le contrôle de la formation et de l’emplacement des dépôts d’uranium associés à des discordances: aperçus issus de la modélisation de transport réactif

“…6d,h,l). These parameters collectively determine whether the aqueous uranium mineralize to form uraninite, or remain in the fluids to be transported elsewhere (Peiffert et al 1994(Peiffert et al , 1996Bali 2012).…”