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Structural elements of the Svecokarelide pericratonic zone in the Karelian Massif (SE Fennoscandia) were identified and described. They were formed after the major events of the Svecofennian tectogenesis. The age ranges of the orogenic stage and the post-orogenic extension collapse were dated, and the depth levels of the corresponding structures were determined. The differentiated exhumation process of deep complexes of the post-Proterozoic Savo–Ladoga movable zone was visualized. The approximate exhumation velocities of the deep material were estimated at certain stages of Precambrian evolution in the zone under consideration. [ABSTRACT FROM AUTHOR]

The results of 40Ar/39Ar dating of pseudotachylytes, first identified in the Paleoproterozoic zonally metamorphosed (greenschist to granulite facies) Ladoga complex of svecofennides, are presented. A wide age range of the formation of pseudotachylytes in the Riphean (1.59–1.31 Ga), presumably caused by the exhumation of deep rocks during the Svecofennian tectonogenesis and the subsequent orogenesis and riftogenesis in southeastern Fennoscandia, has been established. [ABSTRACT FROM AUTHOR]