Research output: Contribution to journal › Article › peer-review
Facies composition and stratigraphic position of the quaternary upper yenisei sequence in the tuva and minusa depressions. / Zol’nikov, I. D.; Novikov, I. S.; Deev, E. V. et al.
In: Russian Geology and Geophysics, Vol. 62, No. 10, 3, 10.2021, p. 1127-1138.Research output: Contribution to journal › Article › peer-review
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TY - JOUR
T1 - Facies composition and stratigraphic position of the quaternary upper yenisei sequence in the tuva and minusa depressions
AU - Zol’nikov, I. D.
AU - Novikov, I. S.
AU - Deev, E. V.
AU - Shpansky, A. V.
AU - Mikharevich, M. V.
N1 - Funding Information: Characterization of the geological and geomorphological position of the Upper Yenisei sequence was financially supported by the Russian Foundation for Basic Research (Project No. 20-05-00605). The comparative analysis of mega-flood facies in the Gorny Altai and in the Upper Yenisei Basin was supported by the Russian Science Foundation (Project No. 19-17-00179). Funding Information: The authors wish to express their thanks to the Khakas Republican Branch of the Russian Geographical Society and personally I.V. Sannikova, the Chair, and the Siberian PGO Company employees N.N. Popova for their help in organizing the field works; V.M. Kolyamkin, T.A. Shatalina for their active participation in the field meeting; and to Russian Geological Institute (VSEGEI ), St. Petersburg, for the financial assistance. Publisher Copyright: © 2021, Novosibirsk State University.
PY - 2021/10
Y1 - 2021/10
N2 - The paper concerns the sediment sequence, which is widespread in the Yenisei valley and in the Tuva and Minusa depressions and also present in the valleys of the southern Chulym plain. The sediments of this sequence were previously described as “Neogene mud-shedding”, as well as moraines, alluvial fan deposits, alluvium of Middle Pleistocene high terraces, and lacustrine sediments. The giant ripple marks on the Upper Yenisei terraces was commonly interpreted as ribbed moraines; however, in recent studies, these ridges have been repeatedly referred to as marks of giant current ripples. Besides, some recently published papers provide description of geology of this sequence fragments suggesting its deposition by cataclysmic floods. Geomorphological analysis of the area shows Pleistocene glaciers to have been localized within the medium–high mountainous areas. The glaciers did not reach the Tuva and Minusa depressions and occupied large areas only in the Todzha basin and on the periphery of the Darkhat basin, forming a glacial dam at its outlet, which resulted in glacial-dammed lakes filling the basin completely. These lakes outburst, and the resultant flooding led to the deposition of megaflood sediments, which we refer to here as the Upper Yenisei sediment sequence. A detailed analysis of its facies architecture revealed similarity of these sediments to those of the Sal’dzhar and Inya sequences in Gorny Altai. Most of the Upper Yenisei megaflood sediments are localized in topographic lows of the Tuva and Minusa depressions. Beyond the Altai–Sayan mountainous area, the megaflood sediments of the Upper Yenisei sequence compose high terraces of the Yenisei, Chulym, Chet’, and Kiya rivers in the southern Chulym plain. The formation of Upper Yenisei sequence dates to the first half of the Late Pleistocene, inasmuch as it contains inset alluvial sediments of the second terrace of the Yenisei River. The available data allow suggesting that the Upper Yenisei sequence formed in the first Late Pleistocene regional glaciation. The Sal’dzhar sequence in Gorny Altai and the fourth terrace of the Ob’ River on the Fore-Altai plain are stratigraphic analogs of the Upper Yenisei sequence. The Upper Yenisei and Sal’dzhar sequences can thus be considered future regional markers serving as a link for the local stratigraphic schemes of the Altai–Sayan mountainous area and adjacent West Siberian plains. The results obtained call for verification by geochronological dating, first of all, by modern luminescence dating methods covering a wider chronological interval than radiocarbon dating.
AB - The paper concerns the sediment sequence, which is widespread in the Yenisei valley and in the Tuva and Minusa depressions and also present in the valleys of the southern Chulym plain. The sediments of this sequence were previously described as “Neogene mud-shedding”, as well as moraines, alluvial fan deposits, alluvium of Middle Pleistocene high terraces, and lacustrine sediments. The giant ripple marks on the Upper Yenisei terraces was commonly interpreted as ribbed moraines; however, in recent studies, these ridges have been repeatedly referred to as marks of giant current ripples. Besides, some recently published papers provide description of geology of this sequence fragments suggesting its deposition by cataclysmic floods. Geomorphological analysis of the area shows Pleistocene glaciers to have been localized within the medium–high mountainous areas. The glaciers did not reach the Tuva and Minusa depressions and occupied large areas only in the Todzha basin and on the periphery of the Darkhat basin, forming a glacial dam at its outlet, which resulted in glacial-dammed lakes filling the basin completely. These lakes outburst, and the resultant flooding led to the deposition of megaflood sediments, which we refer to here as the Upper Yenisei sediment sequence. A detailed analysis of its facies architecture revealed similarity of these sediments to those of the Sal’dzhar and Inya sequences in Gorny Altai. Most of the Upper Yenisei megaflood sediments are localized in topographic lows of the Tuva and Minusa depressions. Beyond the Altai–Sayan mountainous area, the megaflood sediments of the Upper Yenisei sequence compose high terraces of the Yenisei, Chulym, Chet’, and Kiya rivers in the southern Chulym plain. The formation of Upper Yenisei sequence dates to the first half of the Late Pleistocene, inasmuch as it contains inset alluvial sediments of the second terrace of the Yenisei River. The available data allow suggesting that the Upper Yenisei sequence formed in the first Late Pleistocene regional glaciation. The Sal’dzhar sequence in Gorny Altai and the fourth terrace of the Ob’ River on the Fore-Altai plain are stratigraphic analogs of the Upper Yenisei sequence. The Upper Yenisei and Sal’dzhar sequences can thus be considered future regional markers serving as a link for the local stratigraphic schemes of the Altai–Sayan mountainous area and adjacent West Siberian plains. The results obtained call for verification by geochronological dating, first of all, by modern luminescence dating methods covering a wider chronological interval than radiocarbon dating.
KW - Glacial megaflood
KW - Quaternary geology
KW - Tuva and Minusa depressions
KW - Yenisei
UR - http://www.scopus.com/inward/record.url?scp=85117779807&partnerID=8YFLogxK
U2 - 10.2113/RGG20204183
DO - 10.2113/RGG20204183
M3 - Article
AN - SCOPUS:85117779807
VL - 62
SP - 1127
EP - 1138
JO - Russian Geology and Geophysics
JF - Russian Geology and Geophysics
SN - 1068-7971
IS - 10
M1 - 3
ER -
ID: 34562717