На основе комплексного анализа геолого-геофизических данных, полученных в ходе экспедиционных работ 2018 г., выполненных специалистами ФГБУ «ВСЕГЕИ» в рамках ГК-1000/3 (акваториальная часть листов R-57-60), литературных и фондовых данных и корреляции с материалами по прилегающей суше, выделено пять сейсмостратиграфических толщ (ССТ), соотносимых с разными этапами развития территории в плиоцен-четвертичное время, и прослежено их распространение на картируемой площади. Эти материалы позволили существенно уточнить палеоклиматические и палеогеографические реконструкции природных условий неоплейстоцена-голоцена в пределах прибрежного шельфа Восточно-Сибирского моря. На акваторию составлена новая карта четвертичных образований масштаба 1 : 1 000...

The Charlie–Gibbs Fracture Zone is the main transform system in the North Atlantic Ocean. It serves as a primary deep-water gateway for the Iceland–Scotland Overflow Water current. Using high-resolution seismo-acoustic profiling, three types of contourite drift were identified in the valleys of the inactive fractures and active transform of the Charlie–Gibbs Fracture Zone: (1) channel-related drifts; (2) confined drift; and (3) plastered drift. The Iceland–Scotland Overflow Water current is the main agent controlling drift formation in the northern valley and eastern part of the southern valley, while it is suggested that the Denmark Strait Overflow Water or Lower Deep Water dominate in the western part of the southern valley. Examination of two sediment cores shows that the contourite drifts at least at their upper parts consist of alternating muddy and silty contourites and pelagic/hemipelagic sediments. The contourite deposition corresponds to the present interglacial interval. Pelagic/hemipelagic sedimentation prevailed during a glacial interval (marine isotope stages 3–2) and the last glacial/interglacial transition, corresponding with high ice-rafted debris input. The position of the highly productive Subarctic Front over the study area induced the formation of diatom ooze beds at the beginning of marine isotope stage 1 and high-carbonate pelagites during some intervals of marine isotope stage 3.

We present the reconstruction of palaeoenvironmental conditions in the Gdansk, Bornholm, and Arkona Basins of the Baltic Sea over the last millennium. A multiproxy study (including geochemical, XRF, grain size, AMS, and micropalaeontological analyses) of five short sediment cores was performed. The relative age of the sediments was determined based on the Pb distribution along the sediment sequences, as radiocarbon dating has resulted in an excessively old age. The retrieved cores cover two comparable warm periods, the Medieval Climate Anomaly and the Modern Warm Period, for which the increase in surface water productivity was reconstructed. Notably, the production of diatoms was higher during the colder periods (the Dark Ages and Little Ice Age), but this was also the case within the Modern Warm Period. In the Gdansk Basin, the initial salinity increase during the Littorina transgression started after 7.7 cal. a BP. The increased inflow activity was reconstructed during the Medieval Climate Anomaly, even in the Gdansk Basin, despite, in general, very low foraminiferal amounts and diversity. The strongly positive North Atlantic Oscillation Index during this period led to the prevalence of westerly winds over the Baltic region and stronger saltwater intrusions. In the recent sediments, the reconstructed inflow frequency demonstrates a variability against the reduction trend, and a general decline compared to the Medieval Climate Anomaly is seen.

Complex research in the 44th cruise of RV Akademik Boris Petrov Комплексные исследования в 44-м рейсе научно-исследовательского судна «Академик Борис Петров»