Home – Home – Jornals – Earth’s Cryosphere 2026 number 2

This article presents a review of the results from a comprehensive study and dating of contourite deposits in the southwestern Atlantic. It focuses on identifying the sources and transport processes of sedimentary material in the context of Pliocene-Quaternary environmental and climatic changes. The primary emphasis is on research conducted by the Laboratory of Paleoceanography at the Shirshov Institute of Oceanology RAS in collaboration with colleagues over the past decade. The contourite systems examined include those on the continental slope of Argentinian Patagonia, the Santa Catarina and São Paulo plateaus, the Ioffe Drift, and the gravitite-contourite system at the base of São Tomé Seamount. The identification of these systems is based on a comprehensive set of seismoacoustic, lithological, and geochemical data, including variations in magnetic susceptibility. Diagnostic features that distinguish contourites from other types of bottom sediments are discussed. The age of the sediments is determined using biostratigraphy or oxygen isotope stratigraphy and corroborated by accelerator mass spectrometry radiocarbon dating for the last 50,000 years. It is demonstrated that the primary agent in the formation of these contourite systems is the erosional and depositional activity of bottom (along-slope) currents of Antarctic origin, which are a key component of the Atlantic meridional circulation and the global ocean conveyor belt. Consequently, contourite systems preserve a record of the geological and climatic history of the region. Among all the systems considered in this study, the Ioffe Drift contains the oldest sediments, which have accumulated over the last 3.2 Ma. This interval corresponds to the period of modern-type paleoceanographic variability that followed the closure of the Panama Seaway. For the other systems, the sediment cores characterize the glacial-interglacial stages of the Late Quaternary and the associated changes in sea level, climate, and bottom-water circulation.

We have conducted petrological, geochemical, and geochronological research on gabbro intrusions of the Utlyktash complex in the northern part of the West Magnitogorsk zone in the Southern Urals. The studied intrusions are confined to the wings of the Imangulovo syncline formed due to the syncollisional setting and to its surroundings. According to new LA-ICP-MS data, the age of the Uraz gabbro massif is 333 ± 3 Ma. The geochemical features and Nd-Sr isotopic composition of the Utlyktash complex indicate that a weakly depleted PM-type mantle is a source for gabbroids with subsequent significant magma fractionation and minor crustal assimilation (up to 6%). Thermodynamic modeling supports the fractionation model of a single parental melt from which all the studied gabbro bodies crystallized. The ID-TIMS and LA-ICP-MS U-Pb zircon dating (ranging from 0.44 to 2.73 Ga) has revealed the involvement of ancient continental crust and ophiolitic material from the Main Ural fault zone, along which the Magnitogorsk island-arc terrane was thrust onto the Laurussia paleomargin. The geological position of the Utlyktash complex and its geochemical correlation with basalts from the central part of the Magnitogorsk megazone suggest its formation during syncollisional rifting in the early Carboniferous, preceding the assembly of the Laurasia supercontinent.

Metasedimentary melange in the Mt. Sulu-Tyube area bears fine- and medium-grained eclogites, which are predominant within the Kokchetav subduction-collision zone (Kazakhstan), along with scarce porphyroblastic eclogites juxtaposed with rocks of the Zerenda Group. The assemblage of garnet cores ( X _Alm ≤ 0.59, X_Prp > 0.08) with epidote-clinozoisite ( X _Czo = 0.36-0.90), amphibole, ilmenite, titanite, and rutile and the prograde zoning of garnet suggest the nearly isothermal burial of rocks at 11.5-20.5 kbar and 535-570 °С. The growth of high-Mg garnet rims ( X _Prp ≤ 0.31) in paragenesis with omphacite ( X _Jd ≤ 0.35) marks the second stage with nearly isobaric heating up to 645 °С at 21.5 kbar and to 620-690 °С for some samples. Fine- and medium-grained eclogites with uniform structures and with weak zoning of garnet containing omphacite ( X _Jd = 0.20-0.40), rutile, and quartz inclusions formed during heating and limited pressure increase This article presents new data on ore mineral microinclusions and the ore element content of Kamchatka adakites associated with melting of oceanic lithosphere of varying ages in the transition zone from the Pacific Ocean to the Asian continent. Based on these data, hypotheses are made regarding the generation patterns of metalliferous adakites and their role in the formation of copper-gold-silver mineralization in the region. (580-660 °С and 16-19 kbar). Variations in equilibrium temperatures (620-730 °С) indicate their different positions within the subducted lithosphere. The eclogites are similar in signatures to MORB and correspond to low-Ti tholeiitic rocks, but the fine-grained rocks are depleted in Nb, Ta, and Eu and enriched in Th and are characterized by a radiogenic isotopic composition of Sr (⁸⁷Sr/⁸⁶Sr_i = 0.71181-0.72935) and moderately depleted Nd isotopes (ε_Nd(530) = 0.5-4.2), whereas porphyroblastic rocks rehydrated during exhumation show juvenile Nd-Sr signatures (⁸⁷Sr/⁸⁶Sr_i = 0.70212-0.70426, ε_Nd(530) = 6.6-7.2). The contrasting features of eclogites result from the subduction of the rift-related margin of the Kokchetav microcontinent or a more ancient continental structure including variably contaminated N-MORB- and E-MORB-type basites and from the involvement of oceanic or eroded Cambrian island arc rocks in the same process. The differences in the fluid regimes of subduction and exhumation were due to the proximity of a hydrated subduction channel for porphyroblastic eclogites and to the weak fluid permeability of continental lithosphere for fine- and medium-grained eclogites.

We present a thermodynamic model of the interaction between surface water and the flotation tailings of PGE-Cu-Ni sulfide ores from the studied ore district in the Krasnoyarsk Territory. The urgency of the study is determined by the need to assess the long-term stability of mineral assemblages. The aim of the study is to elucidate the regularities of transformation of mineral assemblages during long-term storage. The mineral and chemical compositions of samples from two pits and the chemical composition of aqueous extracts served as initial data. Calculations were carried out in the solid-water-gas system with varying Eh values to simulate different degrees of the system openness to atmospheric oxygen (standard P - T conditions, pCO_{2 gas} = 10^-3.5 atm). Based on the modeling results, it has been established that pyrrhotite remains stable under extremely reducing conditions ( pO_{2 gas} = 10^-79 atm), in which the dissociation of water into atomic oxygen and hydrogen is possible. In general, the obtained models reflect the transition from sulfide to oxide-silicate assemblages, accompanied by a decrease in the number of mineral phases as oxidation progresses. The modeled assemblages are consistent with the parageneses observed in the polished sections. It is shown that the material largely retains its primary mineralogical features even after decades of storage, which is explained by the high content of rock-forming minerals within a dense clay matrix that prevents penetration of oxygen and moisture in amounts sufficient for intense oxidation. The results obtained can be used in the development of technological schemes for the recovery of potentially valuable metals from flotation tailings of PGE-Cu-Ni sulfide ores.

This paper analyzes published data and brachiopod collections available to the authors to determine the systematic composition of brachiopods of the subphylum Rhynchonelliformea from the Cambrian formations of the Siberian Platform. To date, 50 species and 1 taxon identified to the genus level ( Finkelnburgia sp.) have been described. These belong to 15 genera, 10 families (family assignment for two genera remains unclear), and 5 classes. Cambrian brachiopods of the subphylum Rhynchonelliformea from the Siberian Platform can be divided into six associations, each characterized by a specific taxonomic composition, paleogeographic distribution, and stratigraphic range. The most representative brachiopods belong to the class Obolellata. Specimens of this class have been found in North America and Greenland, allowing for relatively confident correlation of Lower Cambrian deposits between North America and the Siberian Platform. The class Strophomenata is also widely distributed. However, of the ten Siberian species of the genus Billingsella Hall & Clarke, eight are endemic. Thus, the occurrences of these brachiopods can be effectively used for genus-level correlation of transitional strata between the Middle and Upper Cambrian. Representatives of other classes (Chileata, Kutorginata, and Rhynchonellata) have lower potential for interregional correlation, although some of them have been found in other regions of the world and can serve as additional tools for correlating distant sections.

The Severo-Ketskaya parametric well was drilled by AO NPC Nedra to a depth of 5200 m in the period 2021-2023. The well is located in the southwestern part of the Pre-Yenisei sedimentary basin in the dome zone of the large anticlinal structure of the same name, buried under the Meso-Cenozoic cover. The well uncovered a new carbonate-terrigenous section of the Vendian and carbonate deposits, presumably of Riphean age, for the Pre-Yenisei sedimentary basin. The article substantiates the stratigraphic boundaries of the Vendian on the basis of geophysical correlations with typical sections of the south-west Siberian Platform, presents the general lithological characteristics of the Vendian section and the exposed part of the Riphean (?). According to the data of the preliminary core study, the results of geophysical studies and tests of objects, the deposits of the Upper and Middle Danilovsky subhorizons are the most promising for oil and gas accumulation in the Vendian rock formations in the borehole drilling area. The results of geochemical studies of sections of parametric wells do not allow us to associate high oil and gas potential with the Proterozoic deposits of the Pre-Yenisei sedimentary basin.

We present the fundamental principles of our technology - GeoArrhenius/SpectrOptim for the justification and reconstruction of compositional kinetic spectra. The advantage of this technology is the reliable separation of gaseous hydrocarbons on the chromatogram and the reconstruction of multicomponent (with an arbitrary number of components) kinetic spectra at the early catagenesis based on neural network modeling. Applying this technology in hydrocarbon system modeling provides the opportunity to accurately assess the volumes of hydrocarbons generated by a source rock and consequently enables the evaluation of hydrocarbon resources in an exploration area. This approach reduces the reliance on external and internal analogies during calculations, as well as the expert opinions of geological researchers.

This special issue of the Geology and Geophysics contains articles presented in the wake of the scientific conference "High-Pressure Mineral Formation Processes: The Origin of Diamonds and Mantle Magmas," dedicated to the 90th anniversary of the birth of the outstanding researcher of diamond formation, Academician Nikolai Vladimirovich Sobolev. The conference took place from June 17–19, 2025, in the Novosibirsk Akademgorodok at the V.S. Sobolev Institute of Geology and Mineralogy, Siberian Branch of the Russian Academy of Sciences. The range of topics covered, from detailed studies of crystal structure defects in individual diamonds and inclusions in it to the regimes and timing of plate tectonics on the early Earth, fully reflects N.V. Sobolev's contribution to the formation of modern understanding of the evolution of the Earth's mantle composition and the formation settings of kimberlites and diamonds.

The main process that changes Earth’s silicate composition after core segregation is the formation and recycling of continental crust. These processes are closely related to the tectonic regimes that operated at different times during Earth’s history. This review combines recent geochemical data and geodynamic models of how continental crust formed throughout Earth’s history, especially during the Hadean and Archean eons. Continental crust cannot form by direct melting of the dry ultramafic mantle. It requires water, mafic protolith, and minerals compatible with high-field-strength elements (Ti, Nb, Ta, Zr, Hf), such as amphibole, rutile, ilmenite, or jadeite pyroxene. For the early Earth, the most likely model involves two stages: first, basaltic or picritic (oceanic) crust is extracted from the mantle, leaving behind a refractory harzburgitic residue. Then, after hydration, the oceanic crust subducts, melts or releases water to flux melting in the mantle, creating continental-crust magmas. Meanwhile, the remaining refractory residue mixes with refractory mantle material, producing a depleted mantle reservoir. Canonical Nb/U and Ce/Pb ratios are unaffected by mantle melting under dry conditions but change during melt generation when amphibole and high-Ti phases are present. Therefore, these ratios are useful indicators of continental crust formation. Geochemical tracers such as (1) Sr isotope compositions of komatiite melts and plagioclase in anorthosites, (2) element ratios in komatiite melts, (3) trace element contents and Hf isotopic compositions of zircon, and (4) decay products of short-lived Sm and Hf isotopes in rocks either support or do not contradict the operation of active continental crust formation and mantle depletion during the Hadean. Production and recycling of continental crust in this period likely involved episodic, short-lived subduction triggered by plumes. Overall, these findings suggest that tectonic regimes in the Hadean (4.4-4.0 Ga after magma-ocean solidification) and in the Eoarchean (4-3.6 Ga) were more dynamic and varied in time and space than previously thought. However, the development of global plate tectonics—requiring a connected network of subduction zones, mid-ocean ridges, and transform faults—could only start later, during the Archean. The causes of the onset of plate tectonics throughout Earth’s history are still debated, and new ideas (such as those involving surface processes, such as the erosion of continents) are being proposed and require further testing.

Electrical resistivity tomography (ERT) has numerous applications. The high demand for ERT is stimulating the active development of equipment and technologies, as well as methods for analyzing, processing, and inversion of ERT data. The use of 3D electrode arrays for surveying complex geoelectrical environments is increasing due to the limitations and shortcomings of 2D electrode arrays. 3D electrode arrays often allow for increased spatial resolution and reliability in the inverted models. The advantages of 3D electrode arrays over 2D electrode arrays for ERT surveying often not obvious. Geophysicists often decline the use of 3D electrode arrays for this reason. This paper reviews ERT technologies that use 3D electrode arrays, methods for building of geoelectric models, their advantages and disadvantages. Based on mathematical modeling/inversion of ERT data, the advantages of 3D electrode arrays and the disadvantages of 2D electrode arrays are demonstrated. We conducted analyses of typical distortions in models and systematized them. We presented a simple 3D electrode array optimized for labor and cost, with current and potential electrodes located on adjacent profiles. We showed that models inverted by ERT data with 3D optimized electrode arrays do not have the distortions typical 2D electrode arrays. Thus, using 3D optimized electrode arrays, labor and cost can be reduced for field work without losing the spatial resolution of models inverted by ERT data. This opens the way for active use of the ERT with 3D electrode arrays to explore ore deposits.

The results of performance the magnetovariational sounding in geologically complex Eastern Kamchatka volcanic belt with the active at present time volcanoes are presented. In investigation the geomagnetic variations received at “Paratunka” observatory and its station “Karymshina”, which is about 18 km apart to southwest from it. Calculated at both site tippers were undergone to 3D inversion by means of ModEM program. During inversion the different start models as homogeneous half-space and the same including the water layer of the nearest Pacific Ocean, taken into account its bathymetry, were used. The carried out inversion let to define the conductive blocks in geoelectrical section at depth range about 10-50 km under volcanic belt. In order to test this result, the 3D inversion of tippers taken by means of solving the direct magnetotelluric task for model containing conductive blocks in the same depth range was performed. In the article the most characteristic horizontal slices and vertical sections of received evaluative geoelectrical model of study area, including Paratunka geothermal area and caldera Karymshina, are presented. The results obtained are compared with the results of a seismic tomography at S-waves, which were get in this region.

The taxonomic composition and distribution of Boreal Carnian ammonoids from northeastern Asia and Arctic Canada have been clarified, the generic assignment of some species has been revised, and their definitions have been standardized. A qualitative comparative analysis of ammonoid assemblages from northeastern Asia and the Canadian Arctic Archipelago has been conducted for the omkutchanicum, armiger, pentastichus, and combined yakutensis and bytschkovi phases. The presence of ammonoids of the genus Boreotrachyceras in the early Carnian of Arctic Canada has been substantiated. This has allowed for the first comparison of coeval ammonoid assemblages of the omkutchanicum phase from northeastern Asia and Arctic Canada, demonstrating the commonality of the ammonoid generic composition of this time throughout the Boreal Realm. It has been established that the early Carnian ammonoid fauna of northeastern Asia differs from that of Arctic Canada by the presence of Tethyan genera (Trachyceras, Striatosirenites) and families (Arpaditidae). A comparative analysis of the ammonoid fauna of the late Carnian has been conducted for the first time, separately for the formation time of the Arctosirenites canadensis beds, equivalent to the pentastichus phase, and for the formation time of the Jovites borealis beds, equivalent to the yakutensis and bytschkovi phases. As a result, for the first time, with phase accuracy, the time of penetration of Tethyan genera into the paleobasins of the Yukon and Arctic Canada (the time of formation of layers with Jovites borealis) was determined, and the belonging of Arctic Canada to the Tethyan Realm was substantiated.

Zones of hydrothermal vein-disseminated, disseminated sulfide, predominantly pyrite, mineralization in Riphean rocks of the Kyvvozhsky region are characterized by elevated contents of Au, Cu, Se, Mo, Ag, Pb, Bi, Sb, Zn. According to the results of the correlation analysis, the following groups of ore elements were identified, within which the strongest positive correlations were established: Ag-Bi-As-Со; Pb-Cu-Zn-Se; Co-Ni-As. Pyrite, arsenopyrite, chalcopyrite, galena, sphalerite, cobaltite, monazite, xenotime, bornite, and covellite are found in association with pyrite in sulfide veinlets. Native gold is rare; particles with peripheral low-grade zones alternate with high-grade gold overgrowths are present. Inclusions of pyrite, pentlandite, monazite, and albite are observed. The gold contains Ag, and sometimes Cu and Pd, as impurities. Judging by the relationships between the minerals, pyrite was the earliest, followed by pyrrhotite, chalcopyrite, and cobaltite, followed by sphalerite, galena, and gold. The formation of sulfide mineralization is associated with hydrothermal processes that occurred in pre-Middle Devonian times, associated with the activation of tectonic-magmatic processes. Geological data, the heavy isotopic composition of pyrite sulfur with a variation in δ³⁴S values from +15.8 to +23.6 ‰, suggest that the most important role was played by regional metamorphic processes that facilitated the mobilization and migration of hydrothermal solutions along faults with the borrowing of various components from the host rocks and subsequent crystallization of sulfides and gold. In some cases, the presence of Cu and Pd impurities in gold indicates a possible influence on the mineral-forming solutions of basic rocks or their partial depth nature as derivatives of basite-hyperbasite magmatism. The Kyvvozhsky district is of interest for primary gold deposits and merits continued exploration.

In this paper, we propose a new chaotic one-way function ChaosKDF that combines the logistic map and cryptographically secure pseudo-random noise from the ChaCha20 generator. The irreversibility of the function is due to the exponential sensitivity to initial conditions and the addition of controlled noise, which leads to rapid degradation of information about the input. Based on information theory, we show that the conditional entropy grows no slower than a linear function of the input size n in bits with an increase in the number of iterations T. This provides a provable lower bound on the complexity of inversion: Ω(ε·2n·T). This makes the function computationally irreversible even for quantum adversaries. It is proven that for an input of at least 256 and an iteration number of 1000, the function is resistant to Grover’s attacks and quantum methods for analyzing dynamical systems, such as QPE and VQA, due to chaos and cryptographic noise. An analysis of side-channel vulnerabilities is performed, and protective measures are proposed, including a fixed number of iterations and energy consumption masking. A comparison with PRF (HMAC-based), HMAC-based KDF, streaming PRF and upgraded KDF demonstrates a balance between security, speed and energy efficiency. This makes it effective for resource-constrained environments such as IoT and PUF systems. The function generates a 56-bit output compatible with modern cryptographic standards. The work opens the way to physically motivated cryptographic primitives, where security is based on dynamic irreversibility rather than algebraic complexity.

In conditions of high socio-economic uncertainty and multiple goals of investors, the use of multicriteria optimization in investment projecting allows finding balanced solutions that take into account various factors and preferences, which increases the efficiency and sustainability of investment projects. The article considers the problem of developing an intelligent computer software system for optimizing adaptive control of the investment design process. It is proposed to use network models and methods as a tool for economic and mathematical modeling of the solution to this problem. The paper presents a new optimization network economic and mathematical model that takes into account the presence of several options for acceptable technologies in the investment projecting process, various options for their implementation and using a vector objective function to assess the quality of project implementation. Based on solving a set of network modeling problems of investment projecting processes corresponding to acceptable technologies and various options for their implementation, using the construction of critical paths and the scalarization method of a specific vector objective function, a technique for solving the formed vector optimization problem is proposed. The developed original methodology allows to implement the process of automation and optimization of adaptive control of the investment projecting process based on network modeling, including coding of all operations of investment projecting, determination of interrelations of operations, sequence and terms of their implementation. Based on the proposed methodology, an intelligent computer software system for optimization of adaptive control of the investment prijecting process in the presence of several technologies and a vector target function has been developed and created. The created intelligent computer system OptimumInvest allows to implement automation, optimization and support of management decision-making using feedback in the implementation of complex investment projects.

The article proves that large language models (LLMs) are economically unviable for signature verification. The apparent low cost of token-based pricing is negated by LLMs’ catastrophically low accuracy (59 % error rate), leading to unjustifiably high expenses. Specialized CNN solutions are significantly more efficient and cheaper. LLMs are fundamentally incapable of analyzing details critical for biometrics. The economic paradox of LLMs turns their accessibility into a financial trap. The study proposes a Total Cost of Ownership (TCO) model for Russia, accounting for sanctions, and recommends using LLMs only as a pre-filter in hybrid systems.

This article examines and summarizes the academic discourse on defining the essence of transaction costs and methods for measuring them. Based on the findings of the study, a new methodology for measuring additional transaction costs arising from changes in the economic environment is proposed. An analysis of the dynamics and level of transaction costs in the Russian economy reveals the specifics of economic agents’ adaptation to uncertainty. The results of the study can be used for planning and implementing measures to improve economic institutions.

The relevance of the research is due to the need to rethink approaches to defining the boundaries of openness of statistical information in the context of modern geopolitical challenges. The scientific novelty of the work lies in a comprehensive analysis of the problem of the openness of statistical data through the prism of national interests and information security. The main results of the study demonstrate that the absolute openness or closeness of statistical data are extremes that do not meet the interests of the state. Unjustified expansion or narrowing of access to statistical data can lead to destabilization of the socio-political situation and increased external threats. The findings of the study confirm that the regulation of the openness of statistical data should be based on the principles of a balance between information openness and national security.

The article examines the situation of large families in the Russian Federation. The analysis of the structure of large families by federal districts has been carried out, the main motives for the birth of the second and third children have been identified, and socio-economic factors affecting the level of large families have been considered. Special attention is paid to government support measures aimed at increasing the birth rate and improving the living conditions of large families. The results of the study allow us to conclude that an integrated approach to family policy is necessary for the sustainable development of Russian society.

The official history of Russia-India relations began in 1953. This was preceded by a centuries-old tradition of trade and cultural exchange between our peoples. This article attempts to systematize the main milestones in the development of relations between the peoples of Russia and India, which served to create a solid modern foundation for trade and economic cooperation. The retrospect is relevant for understanding the existing Russia-India relations in order to identify new opportunities and areas for further expansion and diversification of trade and economic ties between our countries, which meets the strategic objectives of the Russian Federation.

Labor productivity is the most important indicator of the effectiveness of any organization. It is determined by the number of products produced / services sold and the labor costs for their production / sale. In conditions when an organization does not have the opportunity to increase volumes, but it is necessary to get rid of losses and increase the efficiency of using workers’ labor, one of the simplest tools for increasing labor productivity is to bring the number to the actual number. Despite the apparent simplicity of this solution, it involves the implementation of well-thought-out actions, an in-depth analysis of the consequences, and an assessment of the effects. The purpose of the study is to study the experience of personnel management as a tool for increasing labor productivity, identify the features and tools for bringing it to reality based on current standards, and form methodological recommendations for organizations using such a solution in their practice. Research methods: analysis and generalization of experience in managing the number of employees using the example of a division of an industrial enterprise. The analysis made it possible to formulate and identify methodological recommendations for managing the number of personnel in the company’s division with the assessment and receipt of the necessary economic effects. The formulated methodological recommendations can be used in the practice of organizing any industry, provided they are adapted to its specifics.

The article presents a review of international publications on the problematics of Value-Based Management (VBM), based on a representative sample of 40 articles drawn from the total body of research published between 2000 and 2025. The main research directions are systematized into seven thematic blocks, with a summary and analysis of the key findings and results within each block. The review highlights the predominance of empirical studies and the absence of consensus on a number of issues. The paper also outlines the challenges faced by Russian companies in adapting the VBM concept to current conditions.

Due to the rapidly increasing turbulence of the external environment, Russia has once again come to the need to recreate its own self-sufficient national higher education system that will meet the needs of the Russian economy, the Russian mentality and focus on five-year training of specialists. The relevance of the research is determined by the need to understand and adapt the education system to the new labor market conditions and a rapidly changing society. The article presents the results of research conducted by the staff of the Department of National and Regional Economics and the Basic Department of Innovation and Industrial Policy Management at Plekhanov Russian University of Economics, concerning the role of the Russian educational system in the life of society, where it occupies a vast area of intertwining direct and indirect interests, processes, and actions of various parties: from an individual to the whole the population of the country; from individual enterprises, organizations, to the entire production; from the employee to the sphere of labor, the entire socio-economic complex of the country. In the light of recent reforms aimed at changing the structure of the bachelor’s, master’s and postgraduate levels of education, key changes are being considered, starting with the abandonment of the Bologna system and ending with new requirements for graduate training. The authors highlight both the historical component of the changes and current trends that will affect the future of higher education in order to create an effective educational environment that meets the requirements of the labor market.

The evolving of economic development strategies in the resource-dependent regions of the Siberian Federal District (SFD) necessitates economy diversification to mitigate risks associated with the depletion of natural resources. One promising avenue for such diversification is the development of high-tech and science-intensive industries. These sectors are characterized by high value-added production, reliance on environmentally sustainable technologies, and demand for highly skilled labor - factors that can significantly contribute to the socio-economic development of resource-dependent regions. However, the current level of development of high-tech and science-intensive industries in the SFD remains low. To foster their growth, a comprehensive system of state and regional support measures is required, including the implementation of government programs and regional development strategies, tax incentives, provision of preferential loans, and active promotion of clusters, technoparks, and technopolises.

This article provides an integrated description of the economic category “digital platform”, reflecting various levels of economic relations. At the essential level, digital platforms represent an emerging new economic order - the digital economy. In terms of their manifestations, digital platforms act as both a business model and innovative market mechanisms. The paper proposes that the emergence of a platform economy and the resulting increases in economic activity, efficiency, and the creation of new markets contribute to the country’s overall economic growth and the development of the socioeconomic system. The article focuses on digital platform markets and the specific features of their functioning. It is noted that the development of the platform economy requires effective antitrust regulation.

A reaction mechanism for the ignition and combustion of three-component C₃H₈/nC₄H₁₀/iC₄H₁₀ surrogates of alternative fuels based on liquefied petroleum gases has been developed. The mechanism describes the ignition of the surrogates at both high and low temperatures, as well as in the region of inverse temperature dependence of ignition delay time. The mechanism includes 442 reactions for 84 components. The results of testing the mechanism are presented using experimental data: ignition delay time of isobutane mixtures, hydrocarbon gas mixtures containing propane, n-butane, and isobutane (T₀ = 670 ÷ 1478 K, ρ₀ = 1 ÷ 30 atm, φ = 0.3 ÷ 2.0), normal flame propagation velocity in isobutane-air mixtures, and the concentration of the main isobutane oxidation products in a flat-flame burner.

The excitation and propagation of exothermic reaction waves in a closed channel filled with gaseous oxygen at initial pressures of 0.1 to 2 MPa was studied. The waves were excited by a hot nichrome coil coated with a small amount of VM-4 vacuum oil or melted fat. The wave parameters and initial pressures at which flame propagation occurs in the channel were determined.

The most interesting and important gas-dynamic and kinetic parameters of combustion, explosion, and detonation of ammonia/oxygen combustible systems of stoichiometric, lean, and rich compositions with the addition of molecular nitrogen (transition from fuel-oxygen to fuel-air mixtures) are presented. The same data are presented for fuel-air mixtures ranging from the lower to the upper concentration limit and with varying initial pressures. From an explosion safety perspective, the most important data are on the critical initiation energy, which allows for an analysis of the relative hazard of various mixtures. Critical energy E_* is defined as the minimum energy of the initiator that ensures the propagation of combustion and detonation waves in the mixture under study: the lower the E_*, the more hazardous the mixture. Data on the detonation cell size, which is used to determine the characteristic parameters of combustion chambers, which have the dimension of length, are also presented.

Continuous spin and multifront detonation modes of carbon-free ammonia/hydrogen-air fuel-air mixtures were implemented for the first time in a flow-through annular cylindrical combustion chamber with a diameter of 503 mm. Binary fuel (ammonia/hydrogen) with H₂ mass fractions in the fuel of 0.105 ÷ 0.485 was studied in the range of specific mixture flow rates of 22 ÷ 347 kg/(s ∙ m²) at an excess fuel coefficient of φ= 0.47 ÷ 1.55. In ammonia/hydrogen --- air mixtures with fuel of three compositions NH₃ + 8H₂, NH₃ + 4H₂ and NH₃ + 2H₂, single-wave and two-wave modes of continuous spin detonation with a velocity of 1.15 ÷ 1.59 km/s and a wave rotation frequency of 0.73 ÷ 1.81 kHz at φ= 0.73 ÷ 1.2 are realized, and for the NH₃ + H₂ composition --- continuous multifront detonation with two counter transverse detonation waves with a frequency of about 1.0 kHz at φ= 0.72 ÷ 1.0. The region of implementation of continuous spin detonation and continuous multifront detonation modes is determined depending on the ammonia content in the binary fuel and on the pressure in the air manifold. High-frequency sensors measured pressure profiles in the air manifold and in the combustion chamber in the region of rotation of transverse detonation waves. Thrust forces and specific impulses were determined. The highest thrust impulses obtained in the chamber were 2300, 1500, 1350, and 900 s for mixtures with hydrogen mass fractions in the binary fuel of 0.485, 0.32, 0.19, and 0.105.

A study was conducted on the detonation of oxyacetylene mixtures diluted with helium or argon in an extended channel with a flow-through feed of explosive mixture components at atmospheric pressure. The steady-state detonation velocity, temperature, and dynamic pressure of the products were calculated. The limits of self-sustaining detonation in a 26 mm diameter channel were determined. These limits are achieved by diluting an equimolar and stoichiometric mixture to 92% with both helium and argon. Near these limits, near-spin detonation is initiated without a noticeable transition from combustion to detonation by a booster charge of an equimolar oxyacetylene mixture, the volume of which does not exceed 180 cm³ or 13 channel calibers. Detonation coatings made of pure titanium were obtained using both helium and argon as the purging gas. Helium produces a dense coating with a porosity of <0.5% and a microhardness of 370 HV300. Argon can be used to produce coatings with a developed surface and high (tens of percent) porosity in the surface layer, which have potential for use in catalytic reactors and the production of medical implants.

Using the Euler equations in a two-dimensional plane, we numerically study the incidence of a shock wave on a near-wall gas bubble (a transverse cylinder) filled with a hydrogen-oxygen mixture doped with xenon. Gas combustion is modeled using detailed kinetics, taking into account 19 reversible reactions. A high-order finite-difference method of the WENO class is applied. The processes of shock wave refraction and reflection, as well as the focusing of secondary shock waves, are described. Various modes of detonation initiation in the bubble are discovered: direct detonation, refraction and reflection of the wave from the wall, and focusing of shock waves on a plane of symmetry near the wall. Based on a series of calculations, the dependence of ignition modes and threshold Mach numbers of the incident wave on the bubble shape is determined. It has been shown that the combination of wave focusing on the bubble and reflection from the wall leads to a significant reduction in threshold Mach numbers, both compared to a flat layer of combustible gas in front of the wall and compared to a free bubble without a wall.

The results of an experimental study of the ignition of electrode carbon samples heated by an integrated thermal radiation flux are presented. The experiments were conducted using a Uran-1 radiation heating system in an oxygen atmosphere at different pressures (0.1 and 1.1 MPa) with a heat flux density of 75 to 314 W/cm² incident on the sample surface. Ignition temperatures and the dependence of the ignition delay time on the heat flux density were obtained. The measured dependences were used to determine the formal kinetic constants of the process within a heterogeneous ignition model.

Using a coupled combustion model of a metallized composite solid propellant, this study examines transient fuel combustion under harmonic pressure variations above the fuel surface. The combustion model takes into account chemical reactions in the condensed and gas phases. Above the fuel surface, convection and diffusion of gas mixture components, two-phase flow, velocity and thermal nonequilibrium of the phases, and combustion of aluminum particles are considered. Boundary conditions for equal mass and energy fluxes are imposed on the fuel surface. The results of a computational and theoretical study of the dependence of the fuel combustion rate on the amplitude and frequency of pressure oscillations are presented. The study was conducted for two reaction orders in the gas phase. The influence of pressure oscillation frequency on the amplitude of fuel combustion rate variations is determined.

A method based on a genetic algorithm and a reaction rate equation is proposed to determine the parameters of the Lee - Tarver trinomial ignition and growth model for explosives. The method involves extracting characteristic points from the experimental pressure-time curve. The physical flow data is then analyzed and processed using a proprietary program implementing the genetic algorithm, and the Lee - Tarver model parameters are calibrated. The results show that the calculated pressure curve obtained using the model parameters determined by the genetic algorithm is in good agreement with the curve calculated using reference parameters. The maximum error for peak pressure is 6.3%, demonstrating the high accuracy and efficiency of the proposed calibration method.

In self-propagating high-temperature synthesis processes, one of the key issues is the availability and reproducibility of the combustion mode. It is well known that different grades and even different batches of the same grade of powder metals, incorporated during synthesis and obtained from particles of different shapes and sizes, contain varying amounts of gasifiable impurities. Therefore, the combustion rate of powder mixtures of the same composition produced from them can vary severalfold. Previously, the authors of articles for a granulated mixture of 5Ti + 3Si, and in this study for Ti + C mixtures, determined the combustion rate of mixtures with titanium of a single grade in narrow fractions for wide particle sizes of the original titanium powder. These values are well approximated by power laws with a determination coefficient of R² > 0.97. The resulting approximating dependences are presented as baselines. These dependences were used to compare the combustion rates of other titanium grades. For subsequent narrow fractions of other titanium grades, the combustion rate components of powder and granulated mixtures of 5Ti + 3Si, Ti + C were analyzed. Experiments show that the basic dependences of combustion rate on titanium particle size allow us to predict the combustion rate of granulated SHS mixtures of the same composition for narrow fractions of other titanium grades with a level of at least 30%.

The influence of the component ratio, mechanical activation and preliminary compression of the samples on the burning rate and elongation of uncompressed samples during synthesis, on the phase composition and morphology of the combustion products in the (5Ti + 3Si) + (Ti + 2B) system was studied. The combustion front did not reach the lower end of the sample from the initial 5Ti + 3Si mixture. Preliminary compression of the sample, as well as mechanical activation of the 5Ti + 3Si mixture, or the addition of a Ti + 2B mixture allowed the sample to burn to completion. The burning rate and elongation of samples from (100 - x)(5Ti + 3Si) + x(Ti + 2B) mixtures increased after mechanical activation. A tendency towards a decrease in the burning rate with an increase in the 5Ti + 3Si content in the mixtures was recorded. The combustion rate of samples from mechanically activated mixtures increased after compression and remained virtually unchanged for the initial mixtures (except for the Ti + 2B mixture). For some initial mixtures, shrinkage of the product samples was observed after preliminary compression. The maximum combustion rate was measured for samples containing 20% of the 5Ti + 3Si mixture. The dependence of the elongation of samples from the initial (100 - x)(5Ti + 3Si) + x(Ti + 2B) mixtures on their composition exhibited extremes. The phase composition of the combustion products remained unchanged after compression of the samples and mechanical activation of the mixtures.

The effect of preliminary mechanical activation (MA) of carbon black powder on the properties, compaction, and combustion patterns of Ti + C mixtures in an equiatomic ratio of components was studied. It was shown that during the MA process, the arched structure is destroyed and agglomerates of carbon black particles are crushed, which leads to an increase in bulk density by more than three times. It was found that during compaction, carbon black powder behaves as a solid non-plastic material with a high elastic aftereffect (up to 14%). It was shown that in Ti + C mixtures above a relative density of 0.52, a framework of titanium particles is formed, which is responsible for the strength properties of the compacts. It was found that compaction of Ti + C mixtures to a pressure of 50 MPa corresponds to the stage of structural deformation, and above this pressure, the stage of elastic-plastic deformation begins. It is shown that the relative density of compacts from Ti + C mixtures at the onset of the elastic-plastic deformation stage depends on the degree of MA of the carbon black powder. At the same pressure of 50 MPa, mixtures with more dispersed carbon black compact to a higher relative density of 0.65. It is shown that the dependences of the combustion temperature of compacts made from Ti + C mixtures on pressure and density have maxima. Increasing the density of Ti + C mixtures at the structural deformation stage (pressure up to 50 MPa) ensures an increase in the contact surface between the reactants and, consequently, an increase in the combustion temperature. With a further increase in compaction pressure at the beginning of the elastic-plastic deformation stage, the increase in the contact surface between the titanium particles leads to a decrease in the combustion temperature. It was found that the absolute value of the combustion temperature peaks increased with increasing density: for the mixture with the original soot, T_max ≈ 2900 °C at a relative density of 0.58; for the mixture with soot after 3 hours of MA, T_max ≈ 3000 °C at a density of 0.63; for the mixture with soot after 20 hours of MA, T_max ≈ 3200 °C at a density of 0.65. With increasing pressing pressure, the combustion rate decreases due to deterioration in the conditions for removing impurity gases from the volume of the original compacts. The appearance of delamination cracks is shown to lead to a sharp increase in the combustion rate.

An experimental study of the electrical resistance of copper foil under repeated shock compression up to a pressure of 40 GPa was performed in several explosive systems: in a reflected shock wave, under compression in a rigid cage, and in a layered system producing a sequence of waves of increasing amplitude. An improved measuring cell design is proposed, significantly reducing the influence of parasitic eddy currents on the recorded voltage. Under shock compression, the electrical resistance of copper increases monotonically, but the rate of increase depends on the loading history. Under compression by a sequence of shock waves, the electrical resistance of the metal is lower than under compression by a single shock wave (at the same incident wave pressure in a dielectric cage). In this case, the main change in copper's electrical resistance occurs in the first shock wave. In subsequent waves, the electrical resistance also increases, but the final value is lower than in a single shock wave. An assessment of the concentration of defects in the crystalline structure of a copper specimen under complex loading was performed. With repeated compression, the defect concentration is lower than with a single compression (at the same wave pressure or deformation). This means that under complex shock loading, defects are generated predominantly in the early stages of compression, with only a relatively small increase in the number of defects occurring subsequently. Qualitatively, the defect concentration during complex shock loading is determined by the deformation of the material in the first shock wave.

Based on the interpretation of high-resolution seismoacoustic profiles and borehole drilling data in the Barents and Kara Seas, a GIS database was developed, and a digital map of the distribution and depth of the top of submarine permafrost in the Barents and Kara Seas was constructed. In the southwestern and northeastern parts of the Kara Sea, the submarine permafrost boundary partially coincides with the morphostructure of the denudation-tectonic slope of the seafloor. Three regions with significantly different depths of the top of the submarine permafrost were identified on the shelf. On the Barents Sea shelf, the average depth of the submarine permafrost top is (13.3 ± 6.6) m; in the southwestern part of the Kara Sea, (16.7 ± 8.1) m; in the northeastern part, (29.5 ± 15.5) m. The average rate of the subsidence of the submarine permafrost top in the Holocene is 8.2 mm/yr for the Barents Sea and 5.5 mm/yr for the Kara Sea.

The application of capacitive resistivity surveying in conjunction with other methods of geotechnical monitoring of oil and gas gathering pipelines in the permafrost zone is considered to improve monitoring efficiency and informativeness. It is established that electromagnetic surveying is efficient to map frost-susceptible soils because of the dependence of electrical resistivity on the soil pore water content. The use of electrical resistivity allowed the identification of low-resistivity sections along the pipeline, where active frost jacking of the piles occurs. The proposed electrical surveying at shallow depths is effective to identify areas of frost-susceptible soils when used as part of an integrated geotechnical monitoring program.