RAPAKIVI GRANITES AND ASSOCIATING MAGMATISM AS INDICATORS OF TECTONIC MODE TRANSITION DURING THE DEVELOPMENT THE NEOPROTEROZOIC ACTIVE CONTINENTAL MARGIN (YENISEI RIDGE, EASTERN SIBERIA)

New and previously published U-Pb data indicates that in the central part of the Tatarka-Ishimba suture zone of the Yenisei Ridge A-type granitoids including rapakivi granites and associating basic and intermediate rocks were emplaced 651-629 Ma, forming the Tatarka active continental margin complex. We report details of the thermochronological history for these rocks and show the similarity of their magmatic sources, which included input from mixed OIB and E-MORB components. We consider the role of the mafic-felsic magmatism in the formation of gold-antimony mineralization. The formation of rapakivi granites and associating rocks was conditioned by oceanic slab failure at the Cryogenian - early Ediacaran development stage of the Siberian craton active continental margin.