TY - JOUR

T1 - New Data on Late Quaternary Sedimentation in High-Mountain Khikushka Lake (Eastern Sayan): The Role of Climatic and Volcanic Factors

AU - Solotchin, P. A.

AU - Kuzmin, M. I.

AU - Solotchina, E. P.

AU - Bezrukova, E. V.

AU - Strakhovenko, V. D.

AU - Shchetnikov, A. A.

AU - Zhdanova, A. N.

N1 - Funding Information: This work was carried out on state assignment of the Sobolev Institute of Geology and Mineralogy, Siberian Branch, Russian Academy of Sciences (Novosibirsk), and the Vinogradov Institute of Geochemistry, Siberian Branch, Russian Academy of Science (Irkutsk). This work was supported by the Russian Foundation for Basic Research (project nos. 19-05-00219, 19-05-00328, and 20-05-00247), by a joint grant from the Russian Foundation for Basic Research and the London Royal Society (project no. 21-55-10001), and by grants from the Russian Science Foundation (project nos. 19-17-00099 and 19-17-00216). Publisher Copyright: © 2021, Pleiades Publishing, Ltd.

PY - 2021/11

Y1 - 2021/11

N2 - We present the results of a comprehensive study of Late Pleistocene–Holocene sediments from Khikushka Lake located in the high-mountain Zhom-Bolok volcanic area (East Sayan Mountains). The lake is freshwater, endorheic, and of glacial origin; the age of sediments is ~13.8 ka. The sediments have been studied by X-ray diffractometry (XRD), IR spectroscopy, laser grain-size analysis, scanning electron microscopy, X-ray fluorescence analysis, and AMS dating. Detailed mineralogical studies of the Khikushka Lake sediments have been conducted for the first time. It is shown that feldspars, quartz, phyllosilicates, and amphibole prevail in them. Mathematical modeling of complex XRD patterns allowed us to identify chlorite, illite, illite–smectite, chlorite–smectite, muscovite, vermiculite, and kaolinite among layered silicates. The quantitative ratios of these minerals change significantly from the Pleistocene to the Holocene. Despite the close proximity of the volcanoes and multistage Late Quaternary eruptions in the Zhom-Bolok area, only indirect indications of the presence of pyroclastic material were found in the lacustrine sediments studied. Based on the mineralogical, crystallochemical, lithological, and geochemical studies, five evolutionary stages of the Khikushka Lake basin have been identified. Sedimentation in this basin occurred under the influence of both climatic (glacier activity, lake level fluctuations, lake bioproductivity) and geological (composition of rocks within the catchment, Late Quaternary volcanism) factors.

AB - We present the results of a comprehensive study of Late Pleistocene–Holocene sediments from Khikushka Lake located in the high-mountain Zhom-Bolok volcanic area (East Sayan Mountains). The lake is freshwater, endorheic, and of glacial origin; the age of sediments is ~13.8 ka. The sediments have been studied by X-ray diffractometry (XRD), IR spectroscopy, laser grain-size analysis, scanning electron microscopy, X-ray fluorescence analysis, and AMS dating. Detailed mineralogical studies of the Khikushka Lake sediments have been conducted for the first time. It is shown that feldspars, quartz, phyllosilicates, and amphibole prevail in them. Mathematical modeling of complex XRD patterns allowed us to identify chlorite, illite, illite–smectite, chlorite–smectite, muscovite, vermiculite, and kaolinite among layered silicates. The quantitative ratios of these minerals change significantly from the Pleistocene to the Holocene. Despite the close proximity of the volcanoes and multistage Late Quaternary eruptions in the Zhom-Bolok area, only indirect indications of the presence of pyroclastic material were found in the lacustrine sediments studied. Based on the mineralogical, crystallochemical, lithological, and geochemical studies, five evolutionary stages of the Khikushka Lake basin have been identified. Sedimentation in this basin occurred under the influence of both climatic (glacier activity, lake level fluctuations, lake bioproductivity) and geological (composition of rocks within the catchment, Late Quaternary volcanism) factors.

KW - clay minerals

KW - Eastern Sayan

KW - Holocene

KW - lacustrine sediments

KW - Late Pleistocene

KW - modeling of XRD patterns

KW - paleoclimate

KW - volcanic activity

UR - http://www.scopus.com/inward/record.url?scp=85121749459&partnerID=8YFLogxK

UR - https://www.elibrary.ru/item.asp?id=47546059

UR - https://www.mendeley.com/catalogue/8038edf4-5b37-3396-87f5-6ccb983bf821/

U2 - 10.1134/S1028334X21110155

DO - 10.1134/S1028334X21110155

M3 - Article

AN - SCOPUS:85121749459

VL - 501

SP - 938

EP - 944

JO - Doklady Earth Sciences

JF - Doklady Earth Sciences

SN - 1028-334X

IS - 1

M1 - 7

ER -