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The paper presents the quantitative and taxonomic analysis of siliceous microfossils (diatoms and radiolarians) of the ANS-33047 deepsea core (08°16,380′ N, 31°42,870′ W, 4027 mbsl, 5,16 mbsf), from the southern part of the Cape Verde Basin in the eastern equatorial Atlantic. We recognized two groups of radiolarians representing typical tropical-equatorial and temperate North Atlantic microfauna. The assemblage of fossil diatoms includes tropical-equatorial species, as well as freshwater diatoms which indicate the aeolian transfer of particulate matter from Africa. Sporadic distribution of diatoms and radiolarians indicates pulsatile character of silica accumulation in the equatorial zone during the Quaternary, i.e. intermittent periods with relatively intense and definitely weak silica accumulation. Both diatoms and radiolarians were dominant silica producers during the short intervals of marine isotope stages (MIS) 13-8. Their higher concentrations at ca. 513, 430, 300, and 250 ka probably reflect the penetration of highly productive waters of the Equatorial Divergence into the study area. Low numbers of diatoms coupled with the radiolarian abundance during some intervals of MIS 7-1 are probably the evidence of less productive conditions in the surface water layer and the alternating influence of deep-water paleo-upwellings, primarily on the subsurface. The peak of the freshwater diatoms at ca. 464 ka (MIS 12) indicates the possible intensification of deflation processes and the Tropical Easterly Jet transporting aeolian dust f rom African arid areas to the Atlantic Ocean.

Climatic events of the last millennia in the northeastern part of the Norwegian-Greenland basin were reconstructed based on micropaleontological studies of sediments from the AMK-6150 core. New results were obtained from analyses of dinoflagellate cysts, diatoms, and benthic and planktonic foraminifers. These results allow us to infer the time of sediment accumulation and the prevailing natural conditions. According to preliminary data on climatostratigraphy based on the composition of microfossils, the period of sediment formation in the AMK-6150 core does not exceed 7 thousand years. The composition of microfossil assemblages and the results of reconstructions indicate repeated changes in marine environmental conditions during this time. Sediments at the depth of 23-24 cm recorded the beginning of a significant growth of temperature and salinity of surface waters due to a possible increase of the Norwegian Current influence. According to the species and quantitative composition of dinocyst and diatom assemblages, sediments in the short depth range of 14-12 cm accumulated during a period of noticeable decrease in temperature and increased influence of Arctic water masses. The analysis of dinocysts by the method of modern analogues allows reconstruction of the quantitative values of summer paleotemperatures of surface waters and the duration of ice cover. It was found that the cooling episodes and probable formation of seasonal sea ice were possible during the accumulation of sediments at the depths of 29-24, 14-12 and 3-1 cm.