The age of metamorphism of granulite complexes of the Voronezh crystalline massif: The monazite U-Pb geochronology

Abstract

1575 Over recent decades, studies on the reconstruction of the geodynamic evolution of the lithosphere of the East European Platform, including the Voronezh crys� talline massif (VCM), have been carried out actively. The reliability of these reconstructions has some dis� advantages due to insufficient geochronological knowledge of the Precambrian metamorphic regions, which is about 90% of the total volume of the conti� nental crust within the VCM. The Voronezh crystalline massif is a large rise (600 × 800 km) of the East European Platform base� ment, bounded by a system of grabenlike aulacogenes (Pachelmskii, Moskovskii, Gzhatskii, and Toropets� Vyazemskii) from the north and northeast, Dnepr– Donetsk aulacogene from the south, and the Orsha Depression from the south, and the Pricaspian depres� sion from the east. The VCM together with the Ukrai� nian Shield (USh) forms one of Earth’s three crust segments of the Precambrian basement of the East European Craton (Sarmatia) [1]. This VCM belongs to the northeast area of Sarmatia (Fig. 1). The VCM was separated from the Ukrainian Shield in the Phan� erozoic by the Dnepr–Donetsk aulacogene. In the east the Lipetsk–Losevskii volcanogenic belt and the East Voronezh province separate the VCM and the Volga–Uralia crust segment. The main peculiarities of the geological structure of the VCM are reflected in three main types of the struc� –