Palaeozoic terranes of the Balkan Peninsula in the framework of Pangea assembly

Abstract

The presence of three Gondwanan Palaeozoic terranes in the basement of the eastern part of the Balkan Peninsula is revealed by sedimentological, palaeoclimatological, biogeographical and magnetic data. The terranes are, from north to south, the Moesian, Balkan and Thracian terranes. They originate from different parts of Gondwana and Perigondwana. Regional data indicate an en echelon movement of the Moesian and Balkan (incl. Thracian?) terranes from the southern humid zone (in the Ordovician), through the southern arid zone (Moesian terrane during the Devonian) and the equatorial zone (during the Carboniferous), to the northern arid zone (in the Permian). Devonian convergence brought the Moesian terrane and the Dobrudgea periphery of Palaeo-Europe into collisional contact. The collision between the Moesian and Balkan (incl. Thracian) terranes took place during the Late Carboniferous and Permian and was related to the formation of the Variscan orogeny. Upper Palaeozoic molasse sediments blanket a palaeo-relief in predominantly continental environments. Both the collision of the Perigondwanan Moesian and Balkan terranes as well as their accretion to Palaeo-Europe are confirmed by the presence of a megaflora and palynomorphs, similar to those in other Pangea land areas of similar climatic and hypsometric conditions. This study attempts to improve the understanding of the palaeogeographic evolution of the Balkan area. It further tries to explain the regional processes and stages of formation of Pangea.