Heterogeneous ices in ice wedges structure on the Pur-Taz interfluve peatlands of the north of West Siberia

Structure of arctic peatlands with massive ice and structure-forming ice were studied in drained lake («khasyrey») of the Pur-Taz interfluves (the north of West Siberia). The period of accumulation of two-meter thickness of the peat was established to be changed from 8413±90 to 897±90 years BP. Composition of the peat deposits is represented by Betula nana, Sphagnum  sp., Vaccinium oxycoccos, Eriophorum  sp., Equisetum sp. The massive ice is represented by ice wedges with large shoulders and young ice wedges. The central part of the ice wedge is composed by recrystallized crystals of ice veins. Melting zones (elongated crystals of segregated ice and closed-cavity ice) were found in the shoulders of the ice wedge and in the upper part of the young ice wedge. Young ice wedges in the central and lateral parts the main wedge have a similar structure in the cross-section, but they are built by different genetic types of ice: the ice veins or closed-cavity ice with segregated ice. Ice-rich peat contains different types of ice inclusions and subhorizontal ice belts and ice lenses. Ice lenses in the peat can be formed by the segregated ice and/or infiltrated-segregated ice. The hydrochemical composition of the ice wedges, ice lenses, surface water samples and the aqueous extract from peat was analyzed. Hydrochemical analysis did show that polygonal-core ice has basically similar composition with the present-day atmospheric precipitation and surface waters of the polygonal bath; in the area of the shoulder – the composition is intermediate between the ground waters of peat and the central part of the vein. The hydrochemical composition of the ice lenses is similar to the composition of the lake water and peat underlying the active layer. The methane concentrations and its distribution within the ice wedges, peat and lens ice were determined. The closed-cavity ice doesn’t contain methane; the ice wedges with ice veins have minimal methane concentrations; large ice lenses have differentiation of methane concentrations. High concentrations of methane are typical for the frozen peat with inclusions of closed-cavity ice in the uppermost part of permafrost layer; the maximum methane concentration was determined inside the peat with ice lenses. The heterogeneous ices inside the ice wedges, distribution of hydrochemical compounds and methane distribution were conditioned by dynamics of the melting depth during the peatland formation under changing climate of the Holocene in the Arctic.

1. Murton J. Permafrost and periglacial features: ice wedges and ice-wedge casts. Encyclopedia of Quaternary Science. 2013: 436–451. doi: 10.1016/b978-0-44453643-3.00097-2.

2. Shumsky P.A. Osnovy strukturnogo ledovedeniya. Fundamentals of ice structure sciences. Moscow: USSR Academy of Sciences, 1955: 492 p. [In Russian].

3. Dostovalov B.N., Kudryavtsev V.A. Obshchee merzlotovedenie. General permafrost studies. Moscow: Moscow State University, 1967: 403 p. [In Russian].

4. Vtyurin B.I. Podzemnye l’dy SSSR. Underground ice in the USSR. Moscow: Nauka, 1975: 215 p. [In Russian].

5. Popov A.I., Rozembaum G.E., Tumel’ N.V. Kriolitologiya. Cryolithology. Moscow: Moscow State University, 1985: 239 p. [In Russian].

6. Rogov V.V. Osnovy kriogeneza. Fundamentals of Cryogenesis. Novosibirsk: GEO, 2009: 203 p. [In Russian].

7. Zhestkova T.N, Shur Y.L. On the infiltration-segregation mechanism of tabular ground ice formation. Plastovyie ldyi kriolitozonyi. Tabular ground ice of permafrost zone. Yakutsk: IMZ AS USSR, 1982: 105–115. [In Russian].

8. Vasil’chuk Yu.K., Vasil’chuk A.C. Izotopnye metody v geografii. Isotope ratios in the environment. Part 1. Stable isotope geochemistry of natural ice. Moscow: Moscow State University, 2011: 228 p. [In Russian].

9. Fotiev S.M. Arctic peatlands of the Yamal-Gydan province of Western Siberia. Kriosfera Zemli. Earth's Cryosphere. 2017, XXI (5): 3–15. [In Russian]. doi: 10.21782/KZ1560-7496-2017-5(3-15)

10. Trofimov V.T., Badu Yu.B., Vasil’chuk Yu.K., Kashperyuk P.I., Kudryasshov V.G., Firsov N.G. Geokriologicheskoe rayonirovanie Zapadno-Sibirskoy plity. Geocryological zoning of the West Siberian Plate. Moscow: Nauka, 1987: 219. [In Russian].

11. Karta Prirodnykh kompleksov severa Zapadnoy Sibiri. Map of natural complex of the northern West Siberia. Scope: 1:1 000 000. L.: VSEGINGEO, 1991. [In Russian].

12. Katz N.Ya., Katz S.V., Skobeeva E.I. Atlas rastitel’nykh ostatkov v torfe. Atlas of Plant Remains in peat. Moscow: Nedra, 1977: 376 p. [In Russian].

13. Dombrovskaya A.V., Koreneva M.M., Tyuremnov S.N. Atlas rastitel’nykh ostatkov, vstrechaemykh v torfe. Atlas of Plant Remains Occurring in Peat. L.-Moscow: Gosenergoizdat, 1959: 90 p. [In Russian].

14. http://c14.arch.ox.ac.uk.

15. Alperin M.J., Reeburgh W.S. Inhibition experiments on anaerobic methane oxidation. Appl. Environ. Microbiol.1985, 50: 940–945.

16. Savel’ev B.A. Rukovodstvo po izucheniyu svoystv l’da. Guide to the study of ice characteristic. Moscow: Moscow State University, 1963: 198 p. [In Russian].

17. Tikhonravova Ya.V., Slagoda E.A., Rogov V.V., Galeeva E.I., Kurchatov. V.V. Texture and structure of the Late Holocene ground ice in the Northern West Siberia. Led i Sneg. Ice and Snow. 2017, 57 (4): 553–564. doi: 10.15356/2076-6734-2017-4-553-564. [In Russian].

18. Savel’ev B.A. Stroenie i sostav prirodnykh l’dov. The structure and composition of natural ice. Moscow: Moscow State University, 1980: 280 p. [In Russian].

19. Khotinskiy N.A. Golotsen Severnoy Evrazii. The Holocene in Northern Eurasia. Moscow: Nauka, 1977: 198 p. [In Russian].

20. Vasil’chuk Yu.K., Vasil’chuk A.C. Thick polygonal peatlands in continuous permafrost zone of West Siberia. Kriosfera Zemli. Earth’s Cryosphere. 2016, XX (4): 3–15. doi: 10.21782/KZ1560-7496-2016-4(3-15). [In Russian].

21. Batuev V.I., Ganul A.G., Novikov S.M. Age of relict bogs in the northern part of Western Siberia. Vestnik Tomskogo Gosudarstvennogo pedagogicheskogo universitetata. Herald of the Tomsk State Pedagogical University . 2015, 155 (2): 185–191. [In Russian].

22. Vasiliev A.A., Streletskaya I.D., Mel’nikov V.P., Oblogov G.E. Methane in ground ice and frozen Quaternary deposits of Western Yamal. Doklady Akademii nauk. Doklady Earth Sciences. 2015, 465 (5): 604– 607. doi: 10.7868/S0869565215350236. [In Russian].

23. Kritsuk L.N. Podzemnye l’dy Zapadnoy Sibiri. Ground ice of West Siberia. Moscow: Nauchnyy Mir, 2010: 352 p. [In Russian].

24. Bol'shiyanov D.Yu., Svyashchennikov P.N., Fedorov G.B., Pavlov M.V., Tereben'ko A.V. Arctic climate change over the past 10,000 years. Izvestiya RGO. Proc. of the Russian Geographical Society. 2002, 134 (1): 20–27. [In Russian].