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In the geochemical review based on records from cruises of the International Deep Marine Drilling Project (DSDP, ODP, and IODP phases) and other literature data on the main types of Pleistocene sediments in the Atlantic, tables of average arithmetic chemical composition, mean weighted chemical composition, accumulation rates, and mass accumulation rates of chemical components are presented. These tables can be used for the comparative analysis with sediments of the same or other stratons in different oceanic basins, as well as with paleoceanic sediments on the continents. The terrigenous matrix dominates within the lithogenic matter. Using methods of mathematical statistics, we revealed the main geochemical associations and major factors determining the chemical composition of studied sediments. Masses of oxides of petrogenic elements and several trace elements have been calculated for Pleistocene sediments. Average chemical composition of Pleistocene sediments is proposed for the Atlantic. [ABSTRACT FROM AUTHOR]

A geochemical review of Pleistocene sediments in the Indian Ocean has been accomplished based on the deep-sea drilling cruise reports and other literature references. We compiled the database including more than 2000 chemical analyses of sediment samples and tables showing the mean arithmetic composition of lithogenic and biogenic sediments. All data were PAAS-normalized. The dominant role of terrigenous clastics is revealed in the formation of the chemical composition of noncarbonate sediments and noncarbonate matter in planktonic carbonates. The results made it possible to establish the main geochemical associations together with three main (terrigenous, carbonate, and hydrogenous) factors determinating the sediment composition. We calculated the weighted mean chemical composition, as well as the element accumulation rate in the sediments and their mass accumulation rates. All these parameters of the chemical composition can be used for the comparative analysis, with analogous parameters in other ocean sediments within Pleistocene straton in the World Ocean. [ABSTRACT FROM AUTHOR]

An overview of the last works concerning the Recent environment and bottom sediments in the White Sea is presented. Special attention is devoted to the existing schemes of the modern facies structure. Up-to-date factual material allowed the authors to offer a new version of the facies structure. According to this version, the White Sea can be divided into two areas (scale 1 : 5 000 000): Northeastern and Southwestern. The Northeastern facies area includes two facies zones: Western and Eastern. The Southwestern facies area includes three facies zones: Central, Transitional, and Peripheral. In turn, the Peripheral facies zone is divided into the following facies subzones: (1) shallow-water Kandalaksha Bay; (2) Onega Bay, and (3) Severnaya Dvina prodelta and the Letnii Coast. Typical peculiarities of the Recent depositional environment and accumulated marine sediments are presented for all facies areas, zones and subzones. [ABSTRACT FROM AUTHOR]