СLIMATIC AND PHYTOCENOTIC EVENTS OF THE LATE PLEISTOCENE (MIS 5-MIS 3) AT THE SOUTHEASTERN COAST OF THE GULF OF FINLAND

Abstract

The paper analyses a debatable issue concerning the ranking of climatic-stratigraphic units within two marine isotope stages (MIS) - MIS 5 and MIS 4. Palynological records from the Mikulino interglacial sections of the northwestern Russian Plain which are most critical for correlations are reviewed. A representative series of numerical dates obtained by the IR-OSL method, and detailed palynological records enabled a detailed climatic-chronostratigraphic division of the Late Pleistocene sequence of the Voka reference section on the southeastern coast of the Gulf of Finland. The representative palynological spectra provide strong evidence of a warm interval of interglacial rank in the latter half of MIS 5, corresponding to the standard M6, M7, and M8 Mikulino palynozones. Additionally, they highlight a period of significant cooling during MIS 4, characterized by the dominance of periglacial vegetation formations in the study area. This challenges the viewpoint of the extensive Kalinin glaciation during that time, believed to have spread many hundreds of kilometers south of the Gulf of Finland. Data for MIS 3 reveal a two-fold alternation of interstadial and stadial (periglacial) climate intervals during the period between 39 ka and 33 ka.For the first time, detailed reconstructions and datings of climate-phytocenotic successions of paleoclimatic events approximately between 100 ka and 30 ka have been provided for the territory of the East European Plain (and Northern Eurasia as a whole). These events correspond to the latter half of MIS 5, MIS 4, and an interval between 39 ka and 33 ka during MIS 3.