Sources of are matter in formation of metamorphogenic uranium deposits according to isotopic and geochemical data

Carried out are isotopic-geochemical investigations (S.C.O) of minerals of paragenetic uranium mineralization from the deposits localized in rocks subjected to metamorphism of different intensity, namely stratiform deposit in Silurian coaly-clay-carbonaceous shales, iron-uranium and sodium-uranium types. It is established that the character of ore-forming solutions changes with the increase of metamorphism degree. In metamorphous deposits ore-forming fluid has been formed at the expense of porous waters, and uranium has been extracted from enclosing rocks. In metamorphous deposits of green-shaled and amphibolite stages the fluid composition is mixed-metamorphous and abyssal. In ultrametamorphic deposits metasomatic transformations have been accompanied by the inflow of abyssal thermal solutions enriched with carbon dioxide and sulphur. For sodium metasomatites of these deposits enrichment by 13C and 32S isotopes is characteristical that testifies to the inflow of solutions enriched with heavy carbon dioxide and to the increased oxygen potential of ore-bearing fluides