Thermodynamic conditions of formation and geodynamic reconstruction for the eclogites of Beloretsk complex (South Ural)

Despite the significant number of publications covering various aspects of geology and metamorphic rocks metamorphic complex of Beloretsk, mineralogy and geochemistry of eclogite are poorly lit in the literature, and questions about the genetic nature and formation type protolytes and geodynamic conditions of formation of eclogite are almost completely unexplored. The paper presents new data on the thermodynamic conditions of formation of eclogites of Beloretsk complex. It was found that the progressive stage parameter variations reached: T = ~ 620-650 °C, P = ~ 10-13 kbar, and decompression stage: T = 480-500 °C, P = 4.4-5.5 kbar. A geodynamic model of para- and orthorocks of Beloretsk metamorphic complex is suggested, which includes two stages, the first of which was conditioned riftogenesis, manifested at ~ 730-710 Ma; the second stage - the main - was implemented during the orogeny in folded area Timanides under stress (or stress + lithostatic pressure) loads. The conclusion is that Beloretsk metamorphic complex is a typical representative of collision metamorphic complexes.