Инд. авторы:	Strakhovenko V.D., Subetto D., Ovdina E.A., Danilenko I.V., Belkina N., Efremenko N., Maslov A.
Заглавие:	Mineralogical and geochemical composition of Late Holocene bottom sediments of Lake Onego
Библ. ссылка:	Strakhovenko V.D., Subetto D., Ovdina E.A., Danilenko I.V., Belkina N., Efremenko N., Maslov A. Mineralogical and geochemical composition of Late Holocene bottom sediments of Lake Onego // Journal of Great Lakes Research. - 2020. - ISSN 0380-1330.
Внешние системы:	DOI: 10.1016/j.jglr.2020.02.007; SCOPUS: 2-s2.0-85080076419; WoS: 000537315500002;
Реферат:	eng: The analysis of both the mineralogical and geochemical composition and the stratigraphy of Holocene sediments of Lake Onego provided a novel interpretation of their genesis. Their mineral composition suggests that Holocene bottom sediments generally inherit the composition of terrigenous material that enters the lake with river runoff. The predominant authigenic minerals include biogenic opal from diatom skeletons, Fe-illite, and Fe-chlorite, which are the main iron mineral forms in bottom sediments of Lake Onego. Unstable suspension components (illite and chlorite) transform into their ferruginous varieties under humid climate conditions and high concentrations of iron and silicon in the lake waters. Both the presence of ferromanganese nodules in the uppermost part of bottom sediments of Lake Onego and their formation result from the location of the lake in the northern humid zone, geological composition of Fennoscandian crystalline rocks on the Lake Onego watershed, and the presence of an oxidative geochemical barrier into the lake sediment sequence. Late Holocene bottom sediments are represented by two types of sequences: 1) Fe-Mn enriched layers are formed near the sediment-water interface under oxygenated near bottom waters, and 2) such layers are not formed due to low concentrations of oxygen in water; but there are also non-laminated, homogeneous greyish-green silts, similar to those present in the lower parts of the first type of cores. Sedimentation rates (~0.10 cm y−1) were determined by 210Pb- and 137Cs geochronologies. © 2020
Ключевые слова:	Lake Onego; Late Holocene; Mineralogy; Binary alloys; Crystalline rocks; Ferroalloys; Geochemistry; Iron alloys; Manganese alloys; Manganese removal (water treatment); Mineralogy; Minerals; Bottom sediments; Sediments; Stratigraphy; Bottom sediments; Ferromanganese nodules; Geochemical barriers; Geochemical composition; Geological composition; Late Holocene; Sediment water interface; Suspension components; Lakes; Nanocrystalline materials; Geochemistry;
Издано:	2020