Stratigraphy of Cenozoic Deposits and the History of the Latest Stage of Geological Development of the Zaisan Depression (Eastern Kazakhstan)

The Zaisan Depression is a unique geological structure that preserves the most complete sedimentary record of the Late Mesozoic and most of the Cenozoic. A century of studies brought very rich data on the stratigraphy and geological history of the Zaisan sedimentary sequence. The recent scientific progress made it possible to refine the Cenozoic stratigraphic scale of the region. This paper presents the results of a detailed morphostructural analysis and proposes morphotectonic zoning of the Zaisan Depression based on the modern tectonic and geodynamic concepts. New data on magnetostratigraphic subdivision of the Kalmakpai stratotype section, the most complete section of the sedimentary strata of the Zaisan Depression, and on its correlation with the drilling data of its axial part are presented. By the synthesis of magnetostratigraphy with the rich regional biostratigraphic record, the stratigraphy of the region, the dynamics of tectonic movements, and the development of topography and landscapes of the Zaisan Depression and the framing high-mountain structures of Saur-Tarbagatai during the Cenozoic are clarified.