Oil compounds in the bottom sediments of the white sea

Abstract

The content and composition of aliphatic and polycyclic aromatic hydrocarbons in bottom sediments of different areas of the White Sea were studied during low and high waters to estimate the contribution of oil components. It was shown that hydrocarbon (HC) distribution on the border of the Northern Dvina River – Dvina Bay is influenced by the processes that take place in the marginal filter (the riverine-seawater mixing zone) and cause the precipitation of major part of pollutants. With the increase of particles’ grain-size, the HC adsorption capability of sediments rose to a lesser extent comparing to the Corg adsorption. Therefore, the sandy sediments were more enriched in hydrocarbons than the silty ones. The rapid transformation of petroleum low-molecular hydrocarbons leads to the fact that most resistant terrigenous alkanes dominate in the bottom sediments. The separating lakes of the Rugozerskaya Bay were good examples to show that natural processes can form high levels of hydrocarbons in sediments, while their concentrations in the composition of Corg did not exceed 1%.