Ecological State and Mineral-Geochemical Characteristics of the Bottom Sediments of the East Siberian Sea

This paper reports the results of investigations in September 2017 on the radioecological state of bottom sediments of the East Siberian Sea during integrated research of the Siberian Arctic seas on cruise 69 of the R/V Akademik Mstislav Keldysh. Evaluation of the results of γ-spectrometric analysis found that the current specific activity of artificial cesium-137 in sediments is two orders of magnitude below the acceptable level and reflects the influence of global fallout from the atmosphere only. Sediments are not contaminated with heavy metals either. Bottom sediments are represented by silts: pelitic, aleuritic–pelitic, and fine aleuritic with a content of pelite (<0.01 mm) fractions of 40–80%. The western and eastern parts of the East Siberian Sea have differences in the distribution and composition of mineral components and element composition due to the influence of the catchments of the Indigirka and Kolyma rivers, respectively.