pdf № 317, May

DOI: 10.19110/geov.2021.5.1

A modern human bone of the Mesolithic age, found for the first time in Western Siberia, was studied by the number of mineralogical-geochemical methods. Based on the results obtained, the conclusions about paleoecology, food types, and history of human migrations in the Late Pleistocene — Holocene in Siberia presented.

Keywords: Baigara human, Mesolithic, Western Siberia, mineralogical-geochemical properties of bone, paleoecological and historical reconstructions.

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DOI: 10.19110/geov.2021.5.2

Our lithological study of the Quaternary strata in the section of the well 17843 resulted in identification of three sediments sequences of various thickness and composition. In the lower part of the well, at depths of 43.2—27 m (layers 5, 4d and 4c), the sediments were formed probably in fluvioglacial conditions. The sediments are characterized by high content of ilmenite — 7—14 %, and group of titanium minerals — 7—12 %, where concentrations of leucoxene and titanite are increased. The content of chromespinellides increases downwards from 2 to 4.4 %. In the depth interval 25.9—23.6 m (lay 4b), a dense, poorly-sorted silty clay without clastic material is exposed; its genesis is unclear. Clay is characterized by the highest amount of heavy fraction in the section — 1.91 %, and contains an abnormally high amount of magnetite — on average 31 %. The upper 22 m of the sequence (layers 4a and 3—1) are represented by alluvium — well-sorted medium-fine-grained sand with amphibole-ilmenite-garnet-epidote association of heavy minerals and increased amounts of metamorphic minerals — 7—10 %, chromespinellides — 4—6 %, and magnetite — 4—8 %. Such complex of heavy minerals in the sediments, forming the canyon, testifies to the participation of the Ural magmatic and metamorphic complexes in their formation; the supply of minerals from the Kama seems to be very problematic. Palynological analysis data obtained from layers 5, 4d, and 4b reflect a regular vegetation change of the final stages during the interglacial. Spruce-pine forests with fir, cedar, treelike and dwarf birches, alder and willow were gradually replaced by tundra plant communities, where, along with bog-tundra formations, there were xerophytic communities with wormwood Artemisia sp., Chenopodiaceae, and rare Ephedra sp.

Keywords: granulometric composition, mineral composition, palynology, buried canyon, through valley, fluvioglacial deposits, alluvium.

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DOI: 10.19110/geov.2021.5.3

The results of lithological studies of Quaternary deposits in the coastal outcrops of the valley of the lower course of the river are presented. Pechora. In the latitudinal section of the Pechora, two horizons of boulder loams (moraines) and underlying horizons, dividing or overlapping the moraine strata, are exposed to intermoraine sediments of fluvial genesis. Based on the results of lithological studies of textural, granulometric and mineralogical features of fine earth of deposits and petrographic composition of coarse material, it was concluded that material was supplied during the formation of moraines from different terrigenous-mineralogical provinces. The formation of the lower Pechora (Dnieper) moraine is associated with the North-Eastern feeding province, and the upper Moscow (Vychegda) moraine, with the North-West Fennoscandian center of glaciation. The glacial genesis of boulder loams has been confirmed.

Keywords: Pechora, Quaternary deposits, boulder loams, lithology, moraines, Neopleistocene, glacial deposits.

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DOI: 10.19110/geov.2021.5.4

The Museum of the Far Eastern Geological Institute (FEGI) prepared an exhibition «Mineral Resources of the South of the Far East» timed to the anniversary of the Far Eastern Branch of the Russian Academy of Sciences, which is currently on display in the museum. The exhibition presents, brief information about the deposits and published results of research by scientists of the institute in 2016—2020 in leading scientific journals and conference materials, including supported by grants from the Russian Foundation for Basic Research and the Russian Science Foundation.

Keywords: thematic exhibition, mineral resources, South of the Far East.

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