Evolution of the Late Cenozoic basins of Georgia (SW Caucasus): a review

Abstract

Abstract The tectonic and geological evolution of Georgia and the Caucasus, on the whole, are largely determined by its position between the still converging Eurasian and Africa–Arabian lithosphere plates, within the wide zone of a continent–continent collision. The region in the Late Proterozoic–Early Cenozoic belonged to the now-vanished Tethys Ocean and its northern (Eurasian) and southern (Africa–Arabian) margins. Within this convergence zone there existed a system of island arcs, intra-arc rifts, back-arc basins characteristic of the pre-collisional stage. During syncollisional (the Oligocene–Middle Miocene) and post-collisional (the Late Miocene–Quaternary) stages, at the place of back-arc basins were formed fold and thrust belts of the Greater and Lesser Caucasus separated by the Transcaucasian intermontane lowland. Starting from the Late Miocene and as far as the end of the Pleistocene, in the central part of the region, simultaneously with formation of molassic basins and accumulation of coarse molasses there took place volcanic eruptions in subaerial conditions. According to the numerous data obtained during past decades we present a review on the lithological and structural characteristics of these collisional basins and on the coeval magmatic events.