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The contribution of different geochemical processes in the accumulation of metals in dispersed sedimentary matter collected by ADOO was estimated for the first time for the White Sea system. The contents of Al, Fe, Cr, Ni, Со, and Мо (from 60 to 90% of the total content) are mainly controlled by terrigenous processes. The group of geochemically mobile elements includes Mn, Cu, Pb, and Cd; the sum of their forms 1–3, which include the contribution of absorption−desorption and formation of authigenic hydroxides and organic compounds, accounts for, on average, from 52 to 83 Mn %. With increasing water depth, the fraction of the lithogenic form remains either constant or increases insignificantly. In contrast, Mn shows a sharp increase in geochemically mobile forms, heavy metals (Pb, Cu, Mo, Co, and Cd) of which are associated with.

For the first time based on determination of the geochemical occurrence forms of trace metals the main processes that control the accumulation of elements (Al, Mn, Fe, Mo, Cr, Ni, Co, Cu, Pb, Cd, and As) in the recent sediment cores from the White Sea and Barents Sea were quantified. A high-resolution study of the bottom sediment cores allowed us to estimate the short-term variations (periodicity of 10–15 years) in the accumulation of metals to reveal the periods of maximum Fe and Mn contents in the amorphous hydroxides fraction, which serve as effective adsorbents of the trace elements majority, including heavy metals. The Mn/Fe ratio in the amorphous hydroxides phase can be considered as geochemical indicators of early diagenesis.