Deep and crustal factors of thorium-uranium mineralization of the Golovanevskaya zone of Ukrainian Shield

• Published in: Геофизический журнал
• Main Authors: М. А. Yaroshchuk, А. V. Vaylo, А. Ye. Ganevich
• Format: Article
• Language: English
• Published: Subbotin Institute of Geophysics of the National Academy of Sciences of Ukraine 2021-11-01
• Subjects: thorium; uranium; mineralization stages; sources of uranium and thorium
• Online Access: https://journals.uran.ua/geofizicheskiy/article/view/244053

The article discusses the features of the deep and crustal structure of the Golovanevskaya zone, the geochronological sequence of the main stages of its formation. The characteristic of thorium-uranium ore occurrences and deposits is given; and the main stages of their formation. The stages of successive concentrations of uranium and thorium in connection with the processes of sedimentation, volcanism, metamorphism, ultrametamorphism, and tectonic-magmatic activation are determined. The concentration of uranium and thorium was multi-stage and increased with each subsequent geological process. The deep and crustal sources of uranium and thorium, their ratio in the pre-ore main ore-generating stages of deposit formation are considered. It is shown that the formation of deposits became possible in the Proterozoic when neutral and alkaline water-potassium fluids replaced the deep acidic Archean fluids, and the formation of thorium-uranium rock complexes became possible in the crust. The totality of the data obtained is the basis for classifying the thorium-uranium mineralization as the metamorphogenic type. The presence in the Golovanevskaya zone of Lozovatsky, Yuzhny, Kalinovsky deposits, and numerous thorium-uranium ore occurrences determine this zone as promising for developing the thorium-uranium raw material base of the nuclear energy of Ukraine. Thorium-uranium mineralization is also genetically typical for the Kryvyi Rih-Inguletskaya, Orekhovo-Pavlograd interblock suture zones; detailed research is needed to determine their prospects. The confinement of thorium-uranium mineralization specifically to interblock zones is due to a combination of the following main regional features: the presence of Neoarchean thorium-uranium-bearing rock complexes; their metamorphism under conditions of granulite facies; intense ultrametamorphism; development of deep fluid-conducting faults; deep level of the erosional section, in which the products of the rare-metal and pyrite stages of thorium-uranium mineralization were exposed.