FEATURES OF MAGMATISM IN Cu-Mo DEPOSITS IN VARIOUS GEODYNAMIC SETTINGS

Geodynamic settings favorable for development of Cu-Mo ore-magmatic systems were repeated in a zone where the Siberian Craton interacted with the Paleothetys, Paleoasian, and Okhotsk-Mongolian oceans. Large deposits, however, were formed in the Caledonides and Hercynides under post-collision and continent-marginal conditions, respectively. In Caledonides, the Cu-Mo deposits are closely associated in space with plutons made up of intrusive complexes of various geodynamic regimes. The formation of ore-bearing porphyry complexes took place under the conditions of geodynamic reconstruction of the continental margin in the period between the Caledonian collision and Devonian subduction. Centers of porphyric magmatism were probably generated in the collision stage, while ore-bearing porphyry complexes appeared later due to large horizontal displacements along the systems of shears and overthrusts. There are two types of ore-magmatic systems (essentially Mo and essentially Cu) completing the development of gabbro-granite and andesite, respectively, magmatism of ore clusters. In Hercynides, the deposits are confined to volcano-plutonic belts: Cu-Au to frontal and Cu-Mo to back belts. The Upper-Paleozoic magmatism of the back belt overlapped on Caledonides inherits petrogeochemical and metallogenic features of the early magmatism and is completed by the development of more differentiated systems with the increased role of Mo relative to systems in Caledonides.