Hydrogenic ore-forming systems

According to the proposed classification, which takes into consideration hydrodynamics of metalliferous groundwaters, infiltrational and exfiltrational ore-forming systems are defined. These systems comprise large blocks of the continental earth crust with the integrity of hydrogeological structures and are represented, as a rule, by abundant deposits of one or several geological-commercial types. Using the Tien Shan (U); Chu-Sarysu Middle Paleozoic (Pb-Zn); and Late Paleozoic (Cu), West Siberian (U), and East Paratethyan (Mn, U-TR-P, Fe) deposits as examples, geotectonic environments of their formation are reconstructed. The orogenic environments in areas with the moderate orogenic activity and arid climate are mainly favorable for the formation of exogenic-epigenetic uranium deposits characteristic of infiltrational ore-forming systems. In the destructive taphrogenic environment, dominant are exfiltrational ore-forming systems represented by Cu, Pb-Zn, and some other ore deposits. Finally, the tectonoeustatic environments peculiar of stable platformal structures and tectonically quiet epochs, infiltrational and exfiltrational systems, are responsible for the accumulation of sedimentary Mn and Fe ores, bauxites, and phosphorites, as well as the formation of ore-bearing weathering crusts and some uranium deposits. It is shown that the accuracy of the reconstruction of ore-forming systems depends, to a significant extent, on the reliability of geologic-genetic models of particular deposits.