ORE-FORMING PROCESSES AND METALLOGY IN THE PRECAMBRIA OF THE UKRAINIAN SHIELD

Precambrian mineral deposits are associations of rocks and mineral clusters, during the formation of which the processes of concentration of elements were so intense and prolonged that they led to the emergence of very significant geochemical anomalies, which we now interpret as deposits. These processes of unusual and super-powerful concentration of chemical elements could be both single-act events (for example, the formation of a layer of stratiform magmatic cumulates – a chromite deposit), and much more complex polygenic ones, when different ore-forming processes successively replaced each other over a long period of time. Processes of this type were especially evident during the Early Proterozoic stage of the continental crust evolution. Therefore, they are clearly expressed in Proterozoic metallogeny.