Ratio of isotopic parameters δ2H-δ18o in Late Pleistocene and Holocene ice wedge

The subject of this research is the ratio of isotopic parameters of deuterium of heavy oxygen in ice wedges. The authors considered such parameter as inclination of the line of the ration of deuterium of heavy oxygen in ice wedges. Proximal to GMLV (or LLMV) position of isotope values for ice wedge and inclination of the line proximate to 8 suggests that the ice wedge was formed from atmospheric precipitation (winter snow). The article provides separate examples of anomalous deuterium ratios of heavy oxygen with very low ration of line inclination, which in combination with the abnormally low dexc values indicate the indicate isotopic fractionation processes in snow before melting and/or melting snow water before filling frost-cutting cracks. Three author determines the three main types of ratios of deuterium m of heavy oxygen content in ice wedge: a) normal ratio δ2H-δ18O (with line inclination of the ratio proximate to GLMV or LLMW). b) ratio of deuterium  of heavy oxygen to deviation from GLMV or LLMW (with signs of change in the primary isotope signal of atmospheric precipitation), c) anomalous ratio of deuterium of heavy oxygen. It is shown that the first two types  are characteristic to most ice wedge under study in the vast part of the Russian cryolithozone from the European North to the east of Chukotka; the third type is obtained for several Holocene ice wedge in Transbaikal and upper Yenisei River. This may be explained by significant isotope transformation of snow cover in the conditions of distinctly continental climate.

Cryogenic soils in the Vilyuy River Valley (Yakutia)

The object of this research is the cryogenic soils of the territory located in Central Yakutia, in the middle reach of Vilyuy River nearby Makhatta Tukulan with middle-taiga larch woods landscapes. In July 2021, on the right and left banks of the Vilyuy River, twelve soil sections have been formed, which relate to turf-podzols and turf-sub-units of the illovial-ferruginous, sod and alluvial sod, psammozems and stratozems according to to classification and diagnostics of Russian soils (2004). On the slope of the river valley was also formed the soil catena that included elementary geochemical landscapes of river terraces tops and slopes surfaces, as well as middle and high floodplains on the slopes of thermofusional funnels. Soil sections were also formed in flooded beam bottom and well-drained ravine bottom, on sub-horizontal Makhatta Tukulan surface, bottoms and  slopes of thermo-suffosional funnels. The study involves 46 soil samples for measuring the acidity level (pH), electric conductivity (EC), and concentration of total disolved solids (TDS). The explored soils are characterized with pH ranging from 2.81 to 7.78, with most common fluctuations of 5.5–5.6. TDS rates were often within the limit of 10 mg L-1 and rarely exceeded that threshold, however, there were single valyes higher than 50 mg L-1. Thus, the highest EC values (over 100 μS/cm) were measured in surface and subsurface horizons with high organic matter content, whereas mostly mineral horizons had typical EС values within the limit of 20 μS/cm.

Possible changes of the isotopic composition of ice wedge as a result of self-diffusion

  The subject of this research is the assessment of changes of the isotopic composition of ice wedge as a result of self-diffusion. The author offers a relatively simple method of considering the impact of the process of self-diffusion upon redistribution of paleo-isotopic composition that allows accurately and quickly estimating the changes in the values δ18О and δ2H values in ice wedges at different periods of the quaternary (1000 years, 10,000 years, 100,000 years, and 1,000,000 years). The patterns of diffusion process in physico-chemical systems are described by two differential forms of Fick's diffusion laws, which are transformed into Gaussian integral, using six-digit Chambers charts for calculation of the threshold values δ18О. The article applies the experimentally determined real values of self-diffusion coefficient in the ice – D=(2–10)×10-15 m2/s. The values of the Gaussian integral are calculated for time intervals, at different distances between samples with different concentration; for the period of 1,000 years its values in all cases exceed 0.99. For longer time intervals, these values change significantly. The calculated probabilistic values of changes in the concentration of heavy oxygen isotopes in ice wedge under the impact of self-diffusion at different distances and concentration gradients are noticeable only for the time period of over 100,000 years.  

Open database of snow-measuring observations in the south of Western Siberia (2011-2021) and its comparison with data from stationary meteorological observations and satellite monitoring

This article provides a database of the local snow-measuring observations for three river basins in the south of Western Siberia, reviews the methodological peculiarities of the conduct of measurements, and compares the acquired data with the observations at weather stations and available satellite data (CGLS SWE). Observations were carried out in several stages over the period of ten years (2011-2021) in small river basins of Kuchuk, Kasmala, and Mayma Rivers, and reflect the transition from the West Siberian Plain to the Altai lowlands. Total of 25,000 measurements of the parameters of snow deposits (snow mass and snow storage) were made over the years. The database of snow measuring observations is accessible to public. The comparison with station and satellite data indicated significant variances, but also fairly good coherence in some reservoir basins. According to satellite data, the common to basins mean squared error of snow storages was 42.9 mm, which is slightly higher than the claimed by the product engineers (37.4 mm). The time-limited observation data on the permanent routes of weather stations demonstrated the mean squared error of snow storages of 43.5 mm. In winter period, the mean squared error of satellite data gradually increased to the period of maximum accumulation of snow in reservoir basins. Moreover, the errors of satellite data did not depend on the snowiness of the winter period; and most likely, are associated with the parameters of microstructure of the snow mass in separate seasons.

Parageneses of cryogenic formations of gas emission funnels (Part 2). Cryogenic factor in formation of gas funnels

The subject of this research is frozen rocks that compose gas emission funnels in the north of Western Siberia. The object of this research is the cryogenic factor that causes the formation of gas emission funnels. The authors substantiate the thesis that gas emission funnels are cryogenic phenomenon, and the processes preparing the explosion cannot be accurately interpreted without taking these features into account. The analysis of research materials on gas emission funnels, discovered in the north of Western Siberia, allows concluding that surface conditions may have a significant impact upon the formation of gas emission funnels. Special attention is given to consideration of the hypothesis of formation of gas emission funnels due to local heat penetration and gas supply from the depth. The necessary conditions are described. The article provides the examples of using geophysical methods for detecting of gas supply channels. It is concluded that gas emission funnels are the result of self-development of fluid-dynamic geosystems, which represent local, ice subsurface gas-saturated formations that are in a inequilibrium thermodynamic state with respect to the enclosing permafrost formations. The authors' special contribution consists in examination of the external and hidden mechanisms of the emergence of inequilibrium conditions od the mechanism that launches an explosion. The novelty of this research lies in the development of technique for determining the processes that cause the emission of underground gas, based on the analysis of cryogenic formations, which compose the walls of gas emission funnels.

On the reliability of the Vasilchuk’s paleotemperature-isotopiv equations and the establishment of isotopic paleogeocryology

This article is dedicates to the assessment of the contribution of Professor Vasilchuk to the development of isotopic geocryology, as well as testing the reliability of paleogeocryological reconstructions based on the study of isotopic composition of polygonal ice wedges. His discovery of direct dependence of isotopic composition of the sprouts of modern ice wedges on the temperature characteristics of the winter season of 1989 marked the beginning of a promising research of the Holocene and Late Pleistocene syngenetic ice wedges as a reliable paleoclimatic archive. He was first to obtain the characteristics of the winter period for the late Pleistocene and Holocene, as well as create the maps for distributing paleotemperatures for the key periods of Late Pleistocene. The data on the isotopic composition of ice wedges acquired by other scholars later fit into the distribution of paleotemperature within the cryolithozone reconstructed by Professor Vasilchuk. For establishing the degree of reliability of paleotemperature reconstructions, the authors tested the ratio proposed by Y. K. Vasilchuk and regression equations from the works of Konyakhin, Mayer, and Oblogov. The acquired results demonstrate that the values of winter-average and January-average temperatures in reconstruction by Vasilchuk’s ratio always fall within the reliability interval in the entire modern temperature range. Testing the current temperature using regression equations often determine a considerable deviation (often within 3-4°C) from the actual values of winter-average and January-average temperatures.

Palynological diagrams of Holocene sediments and ice wedges at the mouth of the Seyakha River (Zelenaya), Yamal Peninsula

This article examines the sections of the high floodplain of the Seyakha River (Zelenaya) and sections of Holocene peat layers with ice wedges on the third terrace. Palynospectra from sediments and ice wedges of the high floodplain are characterized by a rhythmic fluctuations typical to floodplain facies. The presence of spruce pollen is related to resedimentation, since spruce pollen is detected in the samples with the composition of verifiably resedimented palynomorphs around 10% or higher. The change in composition of the pollen of Siberian pine, scots pine, and birch tree is associated with a change in wind drift, since fluctuations in the composition of the pollen of these taxonomic units do not correlate with fluctuations in resedimented palynomorphs. Therefore, the three periods of increased wind drift and possible increase in pollen productivity can be determined based on mid-period contrast changes in the structure of palynospectra. At the same time, the local peak of cereals is replaced three times by the maximum pollen of dwarf birch and alder. The absence of larch trunks can be substantiated by fires, the traces of which are observed in the section, as well as that larch at the northern limit of its habitat has crumbly wood tissue, which is being rapidly destroyed. Tree limb, needles, and cones usually remain, while the wood tissue is absent. It is assumed that ice wedges formed here 8.5-6 thousand years ago during a single cycle of the change in wind direction and speed , when prevalence of birch tree pollen with some alder pollen at a relatively low pollen concentration was replaced by the dominance of gramineae pollen, and then, dwarf birch pollen in the spring pollen rain. Palynospectra of these ice wedges indicates an increase in the sum of positive temperatures from 8.3 to 6 thousand years.

Geochemical composition of ice wedges in the Batagay yedoma

The subject of this research is the syngenetic ice wedges stripped in the Batagaika crater (67°34 '49" N, 134°46 ' 19 " E), located 10 km southeast of the Batagay settlement. The assessment of macroelement composition of ice was conducted using “Stayer” ion chromatograph (Russia), the chloride ion detection limit is 0.02 mg/l. The article examines the ionic and macroelement composition of ice in suspended and dissolved forms in the Late Pleistocene syngenetic ice wedge of the Batagay yedoma. A comprehensive geochemical research of the Batagaika crater is carried out for the first time. The author explores the upper and lower ice wedges of different age. The main conclusions are as follows: 1) mineralization of Late Pleistocene ice wedge of the Batagay yedoma ranges from 66.56 to 424.8 mg/l, from ultra-fresh to slightly salted; by ionic composition, the ice is bicarbonate-calcium and corresponds to the snow formed under the influence of continental air masses; 2)  the share of Ca contained in the dissolved form does not exceed 20-30%’ as far as other elements, the share of Mg, K, Na, Al, Fe, Mn in the suspended form is over  90%; 3) by mineralization, the Pleistocene ice of Batagay yedoma coincides with the previously studied Pleistocene ice wedges of Yakutia and the Interior Alaska.

Parageneses of cryogenic formations of gas emission funnels (Part 1). Morphology of cryogenic formations

The subject of this research is the cryogenic formations found in gas emission funnels in the north of Western Siberia. The object of this research is cryogenic processes that prepare the explosion, which forms a gas emission funnel. The study of cryogenic structures that shape the walls of gas emission funnels is based on the structural-genetic analysis, which reveals the peculiarities of the initial cryogenic structure of frozen rock, as well as the cryogenic textures modified as a result of dynamic metamorphism. The authors examine such aspects of the topic as the general orientation of plastic and explosive deformations under the influence of high pressure. Analysis is conducted on the role of intra-ground gas filtration in transformation of the initial cryogenic structure. Special attention is given to the patterns of emergence and development of the local geodynamic system that ultimately substantiates the formation of gas emission funnel. The novelty of this research consists in the establishment of paragenetic relations between the processes of gas filtration and deformations of gas-saturated ice surface material (from viscoplastic motion to brittle fracture). The main conclusions are as follows: such external influences as increase in the temperature or pressure change thermodynamic conditions, which lead to multi-phase structural transformation of the initial cryogenic structure of the cryolithic zone; a series of plastic and explosive deformations instigates the intense heat and mass transfer, redistributing the substance in the liquid, solid and gaseous state; in frozen rocks, ice is the most deformable component, thus, most information on the processes preceding the formation of gas funnels can be acquired by studying the morphology of cryogenic formations observed in the walls of the funnels, as well as in the unthawed fragments of frozen rocks thrown to the surface. The authors’ special contribution lies in examination of the complete lifecycle of the development of selected geosystems, from the initial stage –  formation of conditions for decomposition of the gas hydrates, to the final stage – explosion and emission of ice surface material.

Microelements in the Late Pleistocene ice wedges of Seyakha yedoma, east of Yamal Peninsula

The subject of this research is the composition of micro- and macro- rare earth elements in the Late Pleistocene syngenetic ice wedges of the Seyakha yedoma, explored in the outcrop of the Gulf of Ob in the east of Yamal Peninsula (70°9'27.88 "N, 72° 34'8.31" E), north of the Western Siberia. The All-Russian Scientific-research Institution of Mineral Resources after named N.M. Fedorovsky examined the composition of chemical elements in the ice wedges using the methods of atomic-emission spectrometry and mass spectrometry with inductively linked plasma (spectrometers Elan-6100, Optima-4300DV, Perkin-Elmer, Polyvac E-1000, Rank Hilger). The following conclusions were made: 1) Ice wedges of the Seyakha yedoma are rich in macro - and microelements was recorded, which exceeds such in ice wedges of Yakutia by 8-10 times. The high composition of microelements indicates the role of aerosol and soil particles in the formation of chemical composition of ice. The differences between the ice of Yamal and Northeastern Yakutia also testify that the chemical composition reflects the involvement of marine aerosols in ice formation. 2) Rare-earth elements accumulate in the ice of Seyakha yedoma. The composition of all rare-earth elements exceeds the Clarke number in river waters by 69 (Tm ) – 382 (Y) times. 3) Variability of microelement composition within the ice wedge is insignificant, which implies that the water of the polluted with dust and aerosols spring-summer snow is filtered through the entire snow layer and is partially cleaned prior to getting into the ice-break in the ground under the snow.