Archaean terranes, Palaeoproterozoic reworking and accretion in the Ukrainian Shield, East European Craton

Abstract

AbstractThe Ukrainian Shield is a large coherent region of exposed Archaean and Proterozoic crust in the southwestern, Sarmatian part of the East European Craton. It is traditionally divided into blocks, or domains, separated by major suture zones. The Azov Domain in the east and the Podolian Domain in the SW are Archaean complexes that have been highly reworked in the Palaeoproterozoic; in contrast, the Archaean (3.2-3.0 Ga) granite-greenstone terrane dominated Middle Dniepr Domain, in the central part of the Shield, is virtually untouched by Proterozoic processes. Palaeoproterozoic rocks dominate the Kirovograd domain in the central Shield. We review previous and recent geochronological results and demonstrate that the Volyn Domain and adjacent parts of the Ros-Tikich Domain in the NW are largely juvenile, c. 2.2-2.0 Ga segments of Palaeoproterozoic crust accreted to the Palaeo- to Mesoarchaean crust in the Podolian Domain. The Podolian Domain includes 3.65 Ga granitoids, with traces of 3.75 Ga material. It has been reworked, at 2.8 Ga and c. 2.0 Ga. Its temporal evolution is thus similar to that of the Azov Domain in the eastern part of the Shield. However, in view of the complex terrane pattern of Sarmatia, this does not necessarily mean that the Podolian and Azov domains were parts of the same continent in the Archaean.