U-Pb ZIRCON GEOCHRONOLOGY FROM THE GREATER CAUCASUS PALEOZOIC COMPLEXES: NEW DATA AND TECTONIC IMPLICATIONS

New data have been obtained on the U-Pb LA-ICP-MS age of detrital zircons from the Middle-Late Carboniferous and Early-Middle Permian molasses of the Greater Caucasus. The accumulation of molasses in the Carboniferous was associated with multiple-age clastic removal. The Permian was dominated by the source areas of detrital zircons with the narrow age range. According to the results obtained, the Kinyrchad formation dates back to the Ufimian (Early Permian). An ancient population of detrital zircons in the Early-Middle Silurian Ullu-Lakhran formation indicates the presence of blocks of ancient continental crust or products of erosion of the blocks within the feeding province. Analysis of the obtained isotopic data on the ages of zircons from the Bechasyn metamorphic complex and detrital zircons from the molasses of the Peredovoy Range zone and the Bechasyn zone testifies in favor of the peri-Gondwanan origin of the complexes making up the metamorphic basement of these zones and their formation on the Gondwana margin at the end of the Late Riphean – Vendian. U-Pb dating of zircons from the Albian-aged (102±1 Ma, ±1σ) andesibasalts of the Daut River valley raises the question of the probability of manifestation of the Cretaceous magmatic activity in the Greater Caucasus.