Long-term palaeoenvironmental changes recorded in palynologically studied loess-palaeosol and ESR-dated marine deposits of Northern Eurasia: Implications for sea-land correlation

Original materials of pollen analysis and ESR-chronostratigraphic studies provided a basis for reconstruction, chronological subdivision and inter-regional correlation of palaeoclimatic events and sediments of palaeo-shelf, glacial-periglacial and extra-glacial regions of Northern Eurasia within the scope of the Brunhes Epoch. Chronostratigraphic position of the identified palaeoenvironmental events and corresponding horizons in the composite chronostratigraphic column is established on the base of ESR-analyses of subfossil mollusc shells collected from marine, freshwater and terrestrial deposits. The palyno-chronostratigraphic record displays a sequence of 8 intervals (the Holocene included) of warm climate and high sea-level stands, when marine sedimentation occurred on palaeo-shelves, and 7 glacial epochs. The alternating intervals are either fully recorded as complete glacial-interglacial rhythms, or represented by a large enough number of consecutive climatic-phytocoenotic phases. The rhythmic regularity in the sequence of glacial and interglacial events has been inferred from detailed palynological data on reference sections of loess-palaeosol series in the centre of the East European Plain (Arapovichi, Otkaznoe, Likhvin, Strelitsa sections). A clear agreement between long pollen record, directly dated warm-climate-related deposits and other records of palaeoenvironmental evolution known from literature has been established for the upper 15 oxygen isotope stages (OIS 15 to 1). Finally, we come to a conclusion that the integrated climate-chronological sequence may be taken as a basis for inter-regional correlations of palaeo-shelf and terrestrial sediments within Northern Eurasia; it may be used as an intermediate link in the continent-ocean correlations.