Cr, Co and rare earth elements systematics in ice-rafted sediments of northern part of the Beaufort gyre

• Main Authors: P. Shevchenko Vladimir, V. Maslov Andrey, P. Lisitzin Alexandr, N. Novigatsky Alexandr, Stein Rüdiger
• Format: Article in Journal/Newspaper
• Language: English; Russian
• Published: A.N. Zavaritsky Institute of Geology and Geochemistry 2017
• Subjects: арктика; осадочный материал; дрейфующие льды; хром; кобальт; редкоземельные элементы; круговорот бофорта; трансполярный дрейф; arctic; sedimentary material; drifting ice; chrome; cobalt; rare earth elements; the beaufort cycle; transpolar drift; Engineering geology. Rock mechanics. Soil mechanics. Underground construction; TA703-712; Arctic; Arctic Ocean; Arctic Red River; Laptev Sea; Mackenzie River; The Ark; Yenisei River; Arctic Basin; Beaufort Sea; Chukchi; laptev; Mackenzie river; Арктика
• Online Access: https://doi.org/10.24930/1681-9004-2017-3-059-070; https://doaj.org/article/ae4eab36935d44708a72e9abb8b79067

The results of analysis of the systematics of Cr, Co and rare earth elements (REE) in ice-rafted sediments (IRS) of the northern part of the Beaufort Cycle (Arctic Ocean) are considered in the article. The IRS was assembled on the ARK-XIV-1/a cruise of the NIS Polarstern in 1998. The exact position of the sources of the IRS present in the ice has not been established to date. This is due, on the one hand, to the complex ice cycle in the Arctic Basin, on the other - a relatively small amount of data on the actual composition of the IRS. According to the views of most researchers, the main IRS supplier is the wide and shallow Siberian Arctic shelf. In the Beaufort Sea, the distinctive features of which are a much narrower shelf and almost constant presence of ice in the summer period, the conditions for the formation of the IRS are not so favorable. The contents of rare and scattered elements in the IRS samples were determined with the help of INAA at GEOKHI RAS. As a result of the research it was established that variations (La/Yb)N in the IRS from the northern part of the Beaufort cycle are characterized by the values 8.5-15.5. They fully correspond to the average value of this parameter in the suspension of pp. Mackenzie and the Arctic-Red River (8.6 and 8.5) and the mean (La/Yb)N for the crystalline formations of the Canadian Shield (14.4). In the same range are included, the values of (La/Yb)N for the suspension of Yana and Lena rivers (8.7 and 12.4), which may indicate the possibility of the presence in the IRS of material borrowed on the shelf of the eastern Laptev Sea. In the Co-Cr diagram, there is no overlapping of the fields of the compositions of the present bottom sediments of the estuary of Yenisei River, on the one hand, and the eastern part of the East Siberian and Chukchi seas, on the other. Although the sediments of the delta of the Mackenzie River, comparable to the precipitation of the estuary of the Yenisei River. by the content of Cr and differ from them by a noticeably lower content of Co. ...