Mineral and Chemical Composition of Surface Bottom Sediments in Some Regions of the Nordic Seas

The mineral and bulk chemical (basic rock-forming oxides) composition of more than 20 samples of surface bottom sediments taken on a number of cruises of R/V Akademik Mstislav Keldysh in the Nordic Seas (the Mona, Knipovich, Kolbeinsey, and Aegir ridges, the basins of the Norwegian and Greenland seas, the continental slope of Svalbard, the western continental margin of the Barents Sea, etc.) is considered. One of the goals of these cruises was a comprehensive study of the sedimentary system of the Nordic Seas. Our data on the distribution of quartz and calcite in the sediments confirm the idea that the composition of surface bottom sediments at coastal stations is affected by the material coming from the land, while the seaward sediments are affected by the relatively warmer Atlantic waters, leading to their dilution with calcium carbonate, which are mainly produced by planktonic foraminifera. The absence of a correlation between Fe_2O_3^* /SiO 2 and Al 2 O 3 /SiO 2 indicates the effect of mineralogical sorting is not pronounced in the sediments. The distribution of the data points of surface bottom sediments on the Ti/Al–1000*(Cr/Al) diagram is considered. It is concluded that the source of fine aluminosiliciclastics for most of the studied samples is both acidic and basic igneous rocks (volcanic rocks of Iceland) in different proportions. The value of Strakhov’s modulus in the entire sample ranges from 5 to 10. This gives grounds to believe that no products of hydrothermal activity were introduced into the surface bottom sediments of the areas studied by us.