The article considers general information about the structure of the Western Precaucasus and adjacent territories of the Greater Caucasus orogen. The modern mountain structure of the Greater Caucasus, formed on the southern periphery of the Epigercine Scythian plate in the Late Alpine epoch of tectogenesis, is an example of a typical epiplatform orogen. The modern regions of the Greater Caucasus and western Precaucasia in the Mesozoic and Cenozoic up to the end of the Pliocene were part of the marginal continental part of the Parathetis basin. By the end of the Neogene, multi-kilometer Upper Mesozoic-Cenozoic strata of the plate cover was formed in the Greater Caucasus and Western Precaucasus. Probably, the Greater Caucasus orogen began to rise no earlier than the Pliocene, and possibly later – in the Quaternary, no earlier than 2,6–2 million years ago. Accordingly, over a short period of time (2,6–2 million years ago), the orogen experienced rapid uplift. The overlying strata of the plate cover underwent rapid denudation - hypergene and tectonic erosion, as a result, in the axial zone of the orogen, complexes of the granite-metamorphic basement of the Greater Caucasus were exposed, the erosion products of which are recorded in Quaternary molasse. The products of destruction of the orogen of the Greater Caucasus in the bends of the Western Precaucasia form low-power strata of orogenic molasses of Quaternary age. These formations comprise extremely small volumes, which are not comparable with the amplitudes of the uplift of the Greater Caucasus and the estimated capacities (many kilometers) of the strata that overlapped the complex of the Paleozoic base of the Greater Caucasus. The formation of the modern orogen of the Greater Caucasus and coarse Molasses deposits associated with the destruction of this uplift began no earlier than the Pliocene, probably in the Eopleistocene. The high growth rates of the Greater Caucasus orogen and the small volumes of its destruction products accumulated in the Western Precaucasian trough collectively represent a contradictory phenomenon that cannot be explained solely by the factor of erosion of the Greater Caucasus.
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