The conditions of formation of massive ice near the South Tambey gas-condensate field in northern Yamal Peninsula are studied. It is shown that massive ice bodies up to 4.5 m thick occur in the ...Holocene deposits of the high laida and the first terrace. Therefore, they cannot be the remains of glaciers; they are ground ice formations. All three types of massive ice have quite various isotopic compositions: the values of δD range from-107 to-199.7, and δ18O from-15.7 to-26.48per thousand. Such a significant differentiation in isotopic composition is a result of cryogenic fractionation in a freezing water-saturated sediment. The most negative isotope values are even lower in this Holocene massive ice than in the Late Pleistocene ice-wedge ice of Yamal Peninsula.
The original version of this article unfortunately contained a mistake. The spelling of the Yu.K. VASILCHUK’s name was incorrect. The correct name is given below.
Yu.K. VASIL’CHUK
Research has been conducted on the permafrost in the Sentsa River valley for the first time. The investigated units of the permafrost are cryogenic structures of unconsolidated deposits and active ...layer temperature, morphology and cross-section of sizable frost mounds and chemical composition of ice core. The complex pilot studies included borehole drilling, detailed documentation of frost borehole samples, penetrated sections of frost mounds, and river terrace cusps, tachometric survey of the Sentsa river valley, GPS-anchoring of reference sections and boreholes, defining the ice content (humidity), and the lithological, grain-size and microaggregate composition of lacustrine-alluvial sediments. The analysis has been performed by the specialists of the Center for Geodynamics and Geochronology located at the Institute of the Earth's Crust, Irkutsk using modern methods. According to the preliminary data, frost mounds are cryogenic formations of mixed segregation-intrusive genesis. The permafrost thermal regime observations have shown that significant temperature variations occur in the layer 0-2 m, and below the rock temperature is negative in the two-year cycle. It varies from -1.6 °C (in winter) to -0.8 °C (in summer) at depth 4.4 m. The rock temperature is constant (-2.1°C) at depth 10 m.
The series of δ18O values is presented for all precipitation events in Moscow in 2014. Precipitation samples were taken at the observation site of the Meteorological Observatory of Lomonosov Moscow ...State University (MSU MO), and the isotopic analysis was carried out in the isotopic laboratory of the Department of Geography of MSU. The concentration of stable 18O in precipitation over Moscow in 2014 varied from -0.09 to -26.29per thousand. The maximum amplitudes of δ18O were registered in March-April and October. The pronounced interrelation was revealed between the oxygen isotopic composition of precipitation and surface air temperature (the correlation coefficient is 0.85). The computation of back trajectories of air masses and the analysis of weather charts demonstrated that the most isotopically light precipitation is typical of relatively cold air masses slowly moving over the continent during the last five days before precipitation. In this case, the ongoing condensation leads to the progressive isotopic depletion of precipitation (more and more isotope-depleted precipitation is registered). On the contrary, fast air transport from the middle and even from high latitudes of the Atlantic Ocean leads to the relatively constant of δ18O values of precipitation.
The objective of our work is to study the new massive ice deposit in the valley of the Erkutayaha River in the southern part of the Yamal Peninsula, determine the concentration of stable oxygen and ...hydrogen isotopes in the ice and study the pollen and spore in the ice, to determine the conditions of ice formation based on these data, and show that massive ice in these region are of the heterogeneous autochthonic type and segregation (infiltration segregation) and injection genesis similar to those deposits that were recently studied in the regions near Yamal, on the Bovanenkov deposit 1 close to the Harasavey 2, 3 and Marre Sale 4 settlements.
High mountain areas provide water resources for a large share of the world＇s population. The ongoing deglaciation of these areas is resulting in great instability of mountainous headwater regions, ...which could significantly affect water supply and intensify dangerous hydrological processes. The hydrological processes in mountains are still poorly understood due to the complexity of the natural conditions, great spatial variation and a lack of observation. A knowledge of flow-forming processes in alpine areas is essential to predict future possible trends in hydrological conditions and to calculate river runoff characteristics. The goal of this study is to gain detailed field data on various components of natural hydrological processes in the alpine areas of the North Caucasus and Central Tien Shan, and to investigate the possibility that the isotopic method can reveal important regularities of river flow formation in these regions. The study is based on field observations in representative alpine river basins in the North Caucasus （the Dzhankuat river basin） and the Central Tien Shan （the Chon-Kyzyl-Suu river basin） during 2013-2015. A mixing-model approach was used to conduct river hydrograph separation. Isotope methods were used to estimate the contribution of different nourishment sources in total runoff and its regime. ~80, ~D and mineralization were used as indicators. Two equation systems for the study sites were derived： in terms of water routing and runoff genesis. The Dzhankuat and Chon-Kyzyl-Suu river hydrographs were separated into 4 components： liquid precipitation/meltwaters, surface routed/subsurface routed waters.
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![[delta]^sup 18^O and [delta...](http://api.summon.serialssolutions.com/2.0.0/image/issn/XR4PS5YY4K/1028-334X/small "[delta]^sup 18^O and [delta]D variations in Holocene massive ice in the Sabettayakha river mouth, northern Yamal Peninsula")
