Oxidation–hydration weathering of uraninite: the current state-of-knowledge

0435522 - FZÚ 2015 RIV CZ eng J - Journal Article
Plášil, Jakub
Oxidation–hydration weathering of uraninite: the current state-of-knowledge.
Journal of Geosciences. Roč. 59, č. 2 (2014), s. 99-114. ISSN 1802-6222. E-ISSN 1803-1943
R&D Projects: GA ČR GP13-31276P
Institutional support: RVO:68378271
Keywords : weathering of uraninite * paragenetic sequence * bond-valence theory * uranyl–oxide minerals * radiogenic lead * thermodynamics
Subject RIV: DB - Geology ; Mineralogy
Impact factor: 1.405, year: 2014

Oxidation–hydration weathering of uraninite, the most common U-bearing mineral in nature, comprises various physical and chemical processes that lead to the destruction of the fluorite-type structure of uraninite where U is present as tetravalent. This results in replacement of uraninite by weathering products containing U in hexavalent form, i.e. as uranyl ion, UO22+. The final assemblage of the weathering products, uranyl minerals, and their compositions depend on the various factors, namely the composition of the primary minerals and percolating oxidizing fluids that cause the alteration. The knowledge of such processes and stabilities of the uranium minerals is of the great interest namely due to demand for U as the energy source. During the past decade there has been substantial progress in understanding the mineralogy, crystallography and thermodynamics of uranyl minerals and thus a substantially improved understanding of the weathering processes themselves.
Permanent Link: http://hdl.handle.net/11104/0239458