Age of the Late Precambrian Carbonate and Volcanogenic Sequences of Bolshoy Karatau (Southern Kazakhstan): U‒Th–Pb- and Sr-isotopic Data

The Late Precambrian carbonate and volcanogenic sequences that form the structure of the Bolshoy Karatau Ridge in Southern Kazakhstan have been studied. It has been established that carbonates of the Bakyrly Formation accumulated in shallow-water shelf settings between 760 and 820 Ma. Volcanics of the Kainar Formation were formed in the settings of the active continental margin about 745–750 Ma. Analogues of the studied complexes of the Bolshoy Karatau are found in other Ishim–Middle-Tianshan blocks and associated terranes of the western part of the Central Asian Orogenic Belt, which are probably fragments of a single large continental block.