Influence of glacial isostatic adjustment on the upper Volga River valley development

The 100-km long upper reach of the Volga River between the Selizharovo and Zubtsov towns is oriented opposite the Late Valdai ice sheet which covered the Volga River sources, i.e. the area of the Verkhnevolzhskiye Lakes, during the Last Glacial Maximum (LGM), about twenty thousand years ago. Due to the Glacial Isostatic Adjustment (GIA), crustal subsidence occurred in the progalcial area and further from the ice sheet a compensational rise was formed towards which the Volga River valley was directed. The study is aimed at the investigation of the influence of GIA-induced changes in gradients during MIS 2 and the Holocene on the evolution of the Volga River valley. At the key site near the Bolshaya Kosha village (Selizharovo district, the Tver Oblast) it was found that prior the LGM the alluvial aggradation in the valley was most probably associated with the decrease of valley gradient because of the GIA-induced formation of a crustal proglacial flexure. However, the total depth of subsidence was not enough to completely stop the Volga River flow and promote the formation of a proglacial lake. During the LGM the highest (third) and widest river terrace was formed by both river and glacial melt waters. After the LGM the river incision resulted in the formation of a terrace staircase. The incision was caused by the increase of valley gradient due to the glacio-isostatic uplift of the proglacial area in the process of deglaciation. The incision was over in the Mid-Holocene (about 6 kyr BP). The total depth of incision was 15 m and the average incision rate was about 1 mm/year.

1. Astakhov V., Shkatova V., Zastrozhnov A., Chuyko M. Glaciomorphological Map of the Russian Federation //Quaternary International. 420. 2016. Р. 4–14.

2. Auslender V.G. Stratigrafija: chetvertichnaja sistema [Stratigraphy: Quaternary system] // State geological map of the USSR. Scale 1:1 000 000 (novaja serija). Objasnitel’naja zapiska. List O-(35), 36 – Leningrad. L.: MinGeo USSR, VSEGEI, PGO «Sevzapgeologija», 1989. Р. 98–127. (in Russian)

3. Bronk Ramsey C. Bayesian analysis of radiocarbon dates // Radiocarbon. 51 (1), 2009. Р. 337–360.

4. Busschers F.S., Kasse C., van Balen R.T., Vandenberghe J., Cohen K.M., Weerts H.J.T., Wallinga J., Johns C., Cleveringa P., Bunnik F.P.M. Late Pleistocene evolution of the Rhine-Meuse system in the southern North Sea basin: imprints of climate change, sea-level oscillation and glacio-isostacy // Quaternary Science Reviews. 26. 2007. Р. 3216–3248.

5. Bylinskij E.N. Vlijanie gljacioizostazii na razvitie rel’efa Zemli v plejstocene [Influence of glacial isostasy on the Earth relief evolution during the Pleistocene]. M.: Izd-vo RAN, 1996. 210 p. (in Russian)

6. Cohen K.M., Gibbard P.L., Weerts H.J.T. North Sea palaeogeographical reconstructions for the last 1 Ma // Netherlands Journal of Geosciences. 93-1/2. 2014. Р. 7–29. doi: 10.1017/njg.2014.12.

7. Karandeeva M.V. Geomorfologija Rzhevsko-Starickogo Povolzh’ja Kalininskoj oblasti [Geomorphology of Rjev – Staritca part of the Volga River region in the Kalinin Oblast] // Uchjonye zapiski MGU. № 23.Geography. M.: Izd-vo MSU, 1938. Р. 99– 111. (in Russian)

8. Kvasov D.D. Pozdnechetvertichnaja istorija krupnyh ozjor i vnutrennih morej Vostochnoj Evropy [Late Quaternary history of large lakes and inland seas in the Eastern Europe]. L.: Nauka, Leningr. otd., 1975. 278 p. (in Russian)

9. Kjamjarja V.V., Mohov V.V., Semenova L.R. Stratigrafija: chetvertichnaja sistema [Stratigraphy, Quaternary system] // State geological map of RF. Scale 1: 1 000 000 (tret’e pokolenie). Serija Central’no-Evropejskaja. List O-35 – Pskov, (N-35), O-36 – SanktPeterburg. Objasnitel’naja zapiska. S-Pb.: Kart. f-ka VSEGEI, 2012. Р. 149–194. (in Russian)

10. Lavrushin Yu.А. Аllyuvij rek Subarkticheskogo poyasa i periglyatsial’nykh oblastej materikovykh oledenenij [Alluvium of the rivers of the Subarctic belt and periglacial regions of continental glaciations] // Trudy GIN АN USSR. № 87. M.: Izd-vo АN USSR, 1963. 266 p. (in Russian)

11. Mörner N.-A. The Fennoscandian Uplift and Late Cenozoic Geodynamics: Geological Evidence // GeoJournal. 3(3). 1979. Р. 287–318.

12. Mörner N.-A. Eustasy, paleoglaciation and palaoclimatology. Geol. Rundschau. 70. 1981. Р. 691–702.

13. Obedientova G.V. Osnovnye osobennosti geomorfologii doliny Volgi v verhov’e [Main geomorphologic features of the Upper Volga River valley] // Voprosy paleogeografii i geomorfologii bassejnov Volgi i Urala. M.: Izd-vo AN USSR, 1962. Р. 5–40. (in Russian)

14. Obedientova G.V. Formirovanie rechnyh sistem Russkoj ravniny [Formation of fluvial systems within the Russian plain]. M.: Nedra, 1975. 174 p. (in Russian)

15. Obedientova G.V. Erozionnye cikly i formirovanie doliny Volgi [Erosion cycles and the Volga River valley formation]. M.: Nauka, 1977. 240 p. (in Russian)

16. Panin А.V., Baranov D.V. Vliyanie prilednikovykh glyatsioizostaticheskikh deformatsij na razvitie rechnykh dolin severo-zapada Russkoj ravniny [The influence of glacial isostatic adjustment on river valley development in the north-west of the Russian Plain] // Geomorfologicheskie resursy i geomorfologicheskaya bezopasnost’: ot teorii k praktike: Vserossijskaya konferentsiya VII Shchukinskie chteniya. Moskva, MGU imeni M.V. Lomonosova, 18–21 maya 2015 g.: Materialy konferentsii. М.: MАKS Press, 2015. Р. 484–487. (in Russian)

17. Peltier W.R. Mechanisms of Relative Sea-Level Change and the Geophysical Responses to Ice-Water Loading // Sea Surface Studies. R. Devoy (ed.). Springer Science and Business Media, 1987. Р. 57–94.

18. Peltier W.R. Global glacial isostasy and the surface of the iceage Earth: the ICE-5G (VM2) model and GRACE // Annu. Rev. Earth Planet. Sci. 32. 2004. Р. 111–149.

19. Reimer P.J., Bard E., Bayliss A., Beck J.W., Blackwell P.G., Bronk Ramsey C., Buck C.E., Cheng H., Edward s L.R., Friedrich M., Grootes P.M., Guilderson T.P. Haflidason H., Hajdas I., Hatté C., Heaton T.J., Hoffmann D.L., Hogg A.G., Hughen H.A., Kaiser K.F., Kromer B., Manning S.W., Niu M., Reimer R.W., Richards D.A., Scott E.M., Southon J.R., Staff R.A., Turney C.S.M., van der Plicht J. IntCal13 and Marine13 radiocarbon age calibration curves 0–50 000 years cal BP // Radiocarbon. 55(4). 2013. Р. 1869–1887.

20. Sinjugina E.Ja. Geomorfologija Lovatsko-Valdajskogo uchastka Kalininskoj oblasti [Geomorphology of Lovat’ – Valdai area of the Kalinin Oblast] // Uchjonye zapiski MGU. № 23. Geography. M.: Izd-vo MSU, 1938. Р. 16–54. (in Russian)

21. Shhukin I.S. Chetyrjohjazychnyj jenciklopedicheskij slovar’ terminov po fizicheskoj geografii [Four-language encyclopedic dictionary of physical geography terms]. M.: Sovetskaja Enciklopedija, 1980. 703 p. (in Russian)