Deciphering the origin of sedimentary material in the Arctic can contribute to a deeper understanding of modern transport and sedimentation processes. Here, the application of rare earth elements (REEs) is particularly promising, as they can serve as indicators of sources as well as chemical and physical conditions and processes. This study aimed to determine the distribution of REE sources in the bottom sediments and the forms of their occurrence on the East Siberian Arctic Shelf. The concentrations and distributions of the REEs and major and trace metals, grain size, and mineral composition of 72 surficial sediment samples and two sediment cores that were collected from the Laptev and East Siberian seas were studied. Increasing REE content, the predominance of light REE, and close correlation with Zr, Nb, Y, Sc, and Ti were revealed in the Laptev and western East Siberian sea sediments in the zone of influence of the Lena River runoff. The source of the REEs was the eroded Yedoma complex along the coast. The REE content in the sub-colloidal fraction of the sediments was comparable to the REE concentration of the bulk bottom sediments and varied in the East Siberian Sea from 104–220 mg kg-1, with the maximum content around the submarine valley of the Indigirka River, in the Laptev Sea, ranging from 124–197 mg kg-1. The findings could be used to study ice dynamics and to conduct lithostratigraphic and paleoceanographical reconstructions of the Central Arctic.
2023. V. 254, Art. no. 104907

Trace metals in Laptev and East Siberian Sea sediments were analyzed to examine the element distribution pattern and to assess sediment contamination using contamination indices. The maximum Cr, Zn, Ni, Cu, and As concentrations occurred in the deeper parts of the East Siberian and Laptev Seas and the estuarine shelves of the Lena and Yana Rivers, and a high Cd content was observed in the sediment of the eastern part of the East Siberian Sea. The increased Cd concentration could be a result of the large number of phytoplankton supplied by the highly productive waters of the Bering Sea and the sorption capacity of Cd precipitation on Fe and Mn oxyhydroxides in seawater. The mean enrichment factors and geoaccumulation index values for Cr, Ni, Cu, Zn, Pb, and Cd showed no contamination by these metals at any sampling locations; however, slight As enrichment was found, possibly originating from natural sources.
2021. V. 173, Part A. Art. no. 112997

Mercury (Hg) is an important environmental indicator of anthropogenic pollution. In this study, the Hg content in the bottom sediments of the East Siberian Sea was observed to range from 13 to 92 ppb, with an average of 36 ppb. Facies dependence was also observed and expressed as an increase in the Hg concentration in fine-sized sediments on the shelf edge and continental slope, compared to that in the sandy silts and sands of the inner shelf. The Hg accumulation in bottom sediments of the eastern part has increased over the past 150 years due to an increase in global emissions of anthropogenic Hg, which is caused by the transboundary transport of Hg to the Arctic. Moreover, changes in the Hg value, which occur due to the plankton arriving at the bottom sediments because of changes in hydrology and primary production, are thought to be associated with global warming.
2021. V. 168. Art. no. 112426

Using inductively coupled plasma mass spectrometry (ICP-MS), the distribution of rare-earth elements (REE) at the surface and Holocene sediments of the Chukchi and East Siberian Seas was studied in two cores of up to 8.5 ka in age. The total REE concentration of the surface sediments of the Chukchi Sea varied from 62 mg kg−1 to 169 mg kg−1. The NASC-normalized REE patterns were relatively similar to each other and are characterized by a slight enrichment in the middle lanthanides. The total REE concentrations in surface sediments from the East Siberian Sea ranged from 123 mg kg−1 to 200 mg kg−1. The normalized patterns showed a strong predominance of light REE, in particular, La and Ce. The main concentrators of REE are the sand and silt fractions of the sediment. The East Siberian Sea is characterized by REE association with elements contained in heavy stable clastic minerals (Zr, Nb, Hf, Th, and Ti). REE in this region are derived from the erosion of the mainland coast and the New Siberian Islands ice complex, as well as from river discharge, primarily from the Lena River, the basin of which comprises ancient crystalline shield and magmatic rocks enriched in light REE. The sediments in the eastern and southern Chukchi Sea have low REE contents, indicating that the terrigenous flux supplying the Chukchi Sea is through the Bering Strait.
2019. V. 20. P. 148-159