Home – Home – Jornals – Journal of Mining Sciences 2025 number 4

The paper describes methods for three-dimensional interpretation of gravity and magnetic anomalies taking into account the relief of the earth's surface. Parallel algorithms for solving direct problems of gravimetry and magnetometry (calculating field values from sources) are implemented in software for personal computers with graphic accelerators. Based on these algorithms, methods for solving inverse problems on correctness sets have been developed. When modeling, anomaly sources of arbitrary shape are approximated by a dense regular grid, the elements of which are parallelepipeds. Methods for identifying anomalies and localizing sources in the earth's crust, calculating their physical parameters have been applied in modeling the structure of the Kraka ultramafic massifs in the Southern Urals with an area of 50x80 km². The height of the mountain ranges in this area reaches 1043 m, and the difference in relief heights is more than 500 m.

Results on the age estimates of the Paleogene diatom datums derived from the magnetostratigraphy at marine Cenozoic stratigraphic section of the Kvachina Bay, West Kamchatka, are presented. Based on a direct correlation with the Geomagnetic Polarity Scale, it was possible to determine the age of such levels between Subchron C13r (35.10 - 33.73 Ma) and Subchron C9r (27.86 – 27.44 Ma). Of greatest interest are the age dating of the first and last occurrences of Lisitzinia ornata (27.71 Ma and 27.54 Ma respectively), and the first occurrence of Rocella gelida (27.49 Ma). This is the first experience of absolute age estimates of Oligocene diatom biohorizons based on magnetostratigraphy not only in Kamchatka sections, but in the North Pacific region in general. The obtained age estimates of diatom datum levels are compared with the published estimates from the literature on deep-sea cores in various regions of the World Ocean.

In 2024, the head of the Ministry for the Economic Development of the Russian Far East stated: “The main challenge in the development of the Far East and the Arctic is retaining the population" (https://roscongress.org/materials/aleksey-chekunkov-v-novoy-globalnoy-sisteme-koordinat-rol-dalnego-vostoka-budet-vozrastat/). This phrase entered the vocabulary of politicians and publicists and came to mean not a ban on moving to a new place of residence, but, firstly, various ways of encouraging the local population to stay and work in their region and, secondly, preferences for those who decide to move to work and live in areas of particular importance to the state. The article reviews examples of such territories in pre-revolutionary Russia, the USSR, and the Russian Federation, the legitimacy of their status, and preferential regimes. It systematically analyzes the reasons creating two huge megaregions of special state significance - the Far East and the Russian Arctic - whose ambitious development plans require additional labor resources. The article examines the list and adequacy of measures used to “retain the population," the objective difficulties in implementing state personnel policy, and possible ways to overcome them.

Improving the energy efficiency of the constituent parts of the Russian Federation in the context of their sustainable development is fully in line with the global “green agenda " and, due to the adopted domestic regulatory documents, represents a state task. Sustainable development is subject to a number of conditions and factors, including the availability of regions’ own energy resources. Energy self-sufficiency in the general energy sense implies the self-sufficiency of regions not only in terms of electricity, but also in terms of other fuel and energy resources (coal, gas, oil, etc.). However, this article focuses on the issue of regional self-sufficiency in electricity. In this regard, the aim of the article is to construct typological groups of regions depending on the degree of influence on their sustainable development of such indicators as the region’s energy security and the share of energy losses in power grids. The study covers 85 constituent entities of the Russian Federation based on data for 2022 and is based on a methodology developed by the author, which first involves assessing the country’s regions according to the analyzed indicators and then typologizing them. As a result, quantitative and qualitative parameters made it possible to form four groups of regions, differing in terms of sustainable development characteristics. In order to increase the level of sustainable development and energy efficiency of regions, authorities should adopt not typical but typological decisions for each identified group, taking into account the impact of the region’s energy self-sufficiency and energy losses on the gross regional product and gross regional product per capita. This study contributes theoretically to solving the scientific and practical problem of levelling energy imbalances in regional electricity production and consumption models. The practical significance of the study lies in the fact that the results obtained can be used by regional authorities in implementing energy policy in the region, and the proposed tools and mechanisms can be directly applied in their practical activities.

Today, Russia, while adapting to strategic challenges primarily related to the changing world order, is creating its own model of a sovereign national economy. One of the important considerations for achieving this goal is the development of interregional interaction within the country as a tool for fulfilling the potential of its territories. This article studies the problem of structural and technological proximity (STP) of regions as a significant factor in activating economic ties between the subjects of the Russian Federation through the example of the Kemerovo Oblast - Kuzbass. The methodological toolkit for assessing the STP of regions is tested. In order to measure it, the official data of Rosstat for 2022 were used. According to the calculations, the subjects of the Russian Federation, which currently have the strongest positions for the development of cooperation with Kuzbass, were identified. They represent the main macro-regions of the country. Within the framework of a possible partnership with the participants of this group of territories, the Kemerovo Oblast is able to act as both a supplier and a recipient of not only capital, but also knowledge and technology. The latter is especially important in the situation of reforming the resource (raw material) model of Kuzbass performance. The findings can be used to update the strategic planning documents of the Kemerovo Oblast, develop programs and projects aimed at strengthening the processes of its integration and cooperation with other Russian regions through the development of intellectual resources and capital exchange channels.

The article considers the factors of competitiveness of creative industries in Russian regions with a focus on the role of personal branding as a tool for promotion and self-fulfillment of the creative class. The subject of the study embraces the practices of creating and promoting personal brands in the conditions of digital environment and high information saturation. The aim of research is to identify the key strategies ofpersonal brand formation in the creative sector and evaluate their effectiveness to improve the competitiveness of professionals and regions as a whole. The hypothesis is analyzed that successful development of the creative economy requires not only state support, but also natural market mechanisms, including competition, networking and personal brands. The research was conducted by a survey of384 representatives of creative industries in Krasnoyarsk Krai (February-April 2024), the sample was formed by river-sample technology. The respondents represented such spheres as art industry, design, music, theater, cinema, education, media and others, according to the UNESCO classification and the Concept of Creative Industries Development in Russia. The results showed that 42.6% of the participants are purposefully working on their personal brand, and another 36.4% plan to do so. Respondents consider positioning and awareness to be the main attributes of a personal brand. The most popular promotion tool was social networks (27.8%), as they correspond to the logic of the attention economy. More than a third of respondents noted a tangible effect of branding: invitations to projects, new clients, recommendations as a professional and networking. The obtained results can be used to improve the state policy of supporting creative industries, develop the methodological basis for personal branding research and improve the efficiency of professional activity in the creative sphere. The article demonstrates that personal brand is an important resource of competitiveness in the creative economy and requires further study and system support.

The prospects for scientific, technological and innovative development at the level of individual territories depend on many regional characteristics, including the size and balance of accumulated scientific and technological capabilities. The proposed approach to assessing such balance is based on the ideas of innovation and absorption capacities accumulated in a certain territory. The study proposes a typology and positioning of the RF subjects based on the comparison of the highlighted characteristics. The share of people employed in research and development in the total labor force in the region is used as an indicator of innovation capacity. Absorption capacity reflects the localization coefficient of high-tech business. Leading and follower regions are identified for 2016 and 2022. Data from Rosstat and SPARK-Interfax database were used as an empirical basis. The authors performed factor and cluster analyses on indicators describing the state of the region’s economy, its research and technological potential, human resources and digital technologies, as well as the quality of institutions in the field of innovation policy, and identified groups of similar territories. The study identified characteristics that affect the level of innovation and absorptive capacities at the regional level, contribute to their balanced combination, ensuring socio-economic growth and technological independence. These include significant expenditures on research and development, high level of digital technology development, advanced innovation policy. The structure of the economy should be relatively balanced, provide an external environment favorable for the development of new technologies and the production of innovative goods.

The article reviews over long intervals the transition that took place during the Soviet period from an expanded to a narrowed regime of reproduction of the population in Russia, which inevitably leads to depopulation, first latently, and then openly. It is shown that a widespread practice of abortion, which has significantly reduced the number of newborns for a long time, has become the most important factor contributing to the general decreasing trend in the total fertility rate below the threshold level of simple reproduction. In the early 1960s, there was a rapid increase in the number of artificial abortions, accompanied by a drop in fertility. The peak number of abortions recorded in 1965 coincided exactly with the start of the latent phase of depopulation in Russia. In the post-Soviet period, despite a considerable reduction in the number of abortions, both in absolute and relative terms, their number is still high. This has a significant impact on fertility decline, although in recent years the official statistics indicate that there is now less than one abortion for every two births. The article briefly describes the century-old history of legalized abortion in Russia. Its extremely important role in reducing fertility and depopulation in our country is revealed. The long-term and widespread abortive practices, reflecting the reluctance to procreate, systematically undermined the demographic potential and caused enormous damage to demographic security in several important areas for many decades. The authors cite the dynamics of the number of abortions per 100 births in the federal districts in the post-Soviet period, as well as the differentiation of this indicator at the level of federation subjects. The eastern territories consistently show the worst results: the Ural, Siberian and Far Eastern Federal Districts. In recent years, the Siberian Federal District has been ranked first in the country in terms of the number of abortions per 100 births. Among the Siberian regions, the Novosibirsk Oblast stands out, which for many years has been the district leader in this indicator. It is concluded that prevention and minimization of the number of abortions while conducting a well-thought-out and balanced demographic and socio-economic policy aimed at strengthening the family as a pillar of society and improving its financial situation could become a counter-force for increasing the birth rate, especially significant in the context of a prolonged decline in the number of reproductive female populations. The results obtained during the study can be used by federal and regional authorities to make managerial decisions aimed at preventing and reducing the number of abortions, as well as in developing new demographic policy measures and improving socio-economic development strategies in order to create moral and material conditions in society favorable for birth and upbringing of children.

At present, the assessment of the standard of living of the working segments of the population is of particular relevance. The purpose of the study is to adapt the traditional methodology of the HDI approach to assessing the standard of living of the working population in the regions of the Volga Federal District (PFD). The methodology proposed by the authors for calculating the human development index (HDI) of the working population, called “HDI-labor”, includes the following components: 1) the index of median wages, correlated with the cost of a fixed set of consumer goods and services (salary purchasing power index); 2) the index of viability of the working-age population; 3) the index of education, based on the number of students of secondary specialized and higher educational institutions per 10 thousand people of the population. A rating of the regions of the Russian Federation supported by calculations of the new HDI-labor indicator based on data for 2013, 2015, 2017, 2019 and 2021 indicates that the Republic of Bashkortostan in 2021 dropped two positions compared to 2013, taking 35th place. The article also provides comparisons of HDI-labor with HDI-region as a whole and by their components. In 2021, the value of HDI-labor in the Republic of Bashkortostan was 0.375, including the purchasing power index of the median wage - 0.359, the vitality index - 0.311, the education index - 0.454. The value of obtained results is to complement the methodology for assessing the standard of living of the working population based on the HDI approach. This methodology for assessing the standard of living of the working population based on an integral indicator is suggested for use while developing recommendations for improving the standard of living of the working population in the regions of the Russian Federation.

The article considers socio-economic factors of population migration in municipalities on the example of the Sverdlovsk Oblast. The study is based on the concentration analysis of the spatial distribution of migration flows using a combination of autocorrelation and regression modeling methods. The purpose of the study is to identify the significant factors affecting migration flows of population, taking into account the spatial relationship between municipalities. The main objectives of the analysis include the study and identification of statistically significant indicators affecting the resettlement of people. Migration flows have a noticeable impact on the demographic structure of the population, as well as on the state of local and regional labor markets. During the study period from 2010 to 2022, uneven distribution and increased concentration of migrants in large municipalities increased the outflow of population from sparsely populated areas. The use of a set of methods - assessment of migration flows concentration, spatial autocorrelation and spatial regression analysis - allows us to fully determine the zones of concentration of migration flows and identify factors affecting resettlement within the Sverdlovsk Oblast with the further purpose of using the study to adjust and plan the development of the territory.

Since 2023, according to the decree of the Government of the Russian Federation, Berezovsky and Beloyarsky municipal districts of Khanty-Mansi Autonomous Okrug-Yugra are the districts of the Arctic Zone of the Russian Federation. These are the two districts where indigenous small-numbered peoples of the region - Khanty and Mansi - predominantly live. The goal of the article is to analyze the situation with indigenous minorities at municipal labor market and to identify peculiarities of their embeddedness. Research hypothesis: In Arctic regions of the Khanty-Mansi Autonomous Okrug-Yugra, representatives of Khanty and Mansi demonstrate a lower level of employment rate comparing to the rest of the region’s population, which indicates insufficient integration at municipal labor market and a lower level of embeddeness associated with lack of vocational education (65.2% of Khanty and Mansi) and insufficient qualification. The methodology of the research is associated with a comparison of data from open sources. It also includes recommendations for improving the situation at the labor market in the Arctic regions of Khanty-Mansi Autonomous Okrug-Yugra, for example, recommendations for of special educational programs, development of traditional crafts, etc. The analysis has shown the correspondence of labor resources with geographic location of enterprises. Khanty and Mansi live in three municipal districts which are considered to be the least balanced in terms of labor market - Berezovsky, Beloyarsky, Kondinsky. The analyzed data for 2023 indicates the aggravation of the situation at municipal labor market for Khanty and Mansi and indicates an acute need for new measures to be taken.

This article is devoted to the analysis of the effectiveness of state support measures for the socio-economic development of Russian regions, based on the assessments by civil servants in the constituent entities of the Russian Federation. The subject of the study is the perception by regional authorities of various instruments of federal support. The purpose of the work is to identify the problems that arise in the implementation of these measures and to develop proposals for their improvement. The methodological basis of the study was the analysis and generalization of the results of a survey conducted by the RANEPA Center for Regional Policy in cooperation with the Commission of the State Council of the Russian Federation on Economics and Finance in September-October 2024. The survey covered civil servants of various subjects of the Russian Federation. The results of the analysis showed significant differences in estimates of the effectiveness of support measures depending on the group of regions. Some problem areas were identified, in particular, the supervision of deputy prime ministers in the federal districts received low marks. The assessment of the release of funds within the framework of debt restructuring on budget loans turned out to be ambiguous. The tools of the “infrastructure menu" and preferential territories, in general, received positive reviews. The findings of the study contribute to understanding the attitude of regional authorities towards federal support and identify areas for improving its effectiveness. The results obtained can be used to improve the mechanisms of state support for regional development, optimize the allocation of resources and increase the effectiveness of the implementation of federal programs. They may be of interest to government authorities, researchers of regional economics and experts in the field of management.

The article examines the most important modern environmental challenges and the risks and threats caused by them, taking into account both national and regional and international aspects of the growing importance of the environmental agenda. An analysis of the cause-and-effect relationships between the presence of hazards contained in a particular challenge and the real damage that can be caused to the natural environment, living conditions and human health has been carried out. Possible ways to prevent potential risks and threats to the environmental and economic development of the country are proposed. Among the identified challenges, emphasis is placed on challenges that contain risks and threats caused by factors of both a global nature and those associated with the peculiarities of the formation of environmental and economic policy in Russia and its regions. These include tightening environmental requirements for products on foreign markets, taking into account the technologies used for their production and the resulting carbon footprint; close intertwining of environmental issues with technological and economic problems; changes in environmental regulations within the country in connection with external sanctions imposed on it, and others. The statement about the existential nature of the considered environmental challenges is substantiated. It is concluded that the existing institutional environment in Russia, which also determines the effectiveness of state environmental policy, requires transformation, subject to active state support in the field of innovation, technological sovereignization of the economy based on domestic best available technologies and other measures based on socio-economic and environmental motivation, based primarily on the principles of economic efficiency and environmental justice. The proposals made for improving the mechanism of environmental and economic policy can be useful in developing instruments for regulating the environmental sphere at all levels of management.

The article discusses new opportunities and risks on the southern border of the taiga, where swamps are being naturally drained due to climate warming. Highlighting the dangers that arise in these conditions, the author puts the high risk of fires first in connection with the need to take emergency measures. The paper notes that drainage of swamps has stopped all over the world and work on their restoration is beginning. The difficulties of assessing the likelihood of fires, as well as developing technologies for marsh restoration (re-wetting), are discussed. Along with new dangers, the author describes new opportunities that appear for the economy in connection with the processes occurring on the southern border of the taiga. Among the new possibilities, the article discusses new directions for the use of peat and a more active involvement of wild plants from the swamp environment in economic circulation. Particular attention is paid to the problem of increasing soil fertility in areas cleared of swamps and taiga. Options for changing crop rotations and introducing new agricultural crops into them are also considered.

In this paper we consider nonlinear fractional differential equations involving the new Caputo-Fabrizio derivative of order γ ∈]1, 2[. We convert the fractional problem to an equivalent nonlinear Volterra integro-differential equation of the second kind, then we investigate the existence and uniqueness of its solution under certain given conditions by using the Schauder fixed point theorem. Finally, we numerically solve the proposed fractional problem by applying the Nyström method, and we provide some suitable examples to support our study.

Conjugate gradient methods represent a powerful class of optimization algorithms known for their efficiency and versatility. In this research, we delve into the optimization of the Generalized Descent Symmetrical Hestenes-Stiefel (GDSHS) algorithm by refining the parameter c, a critical factor in its performance. We employ both analytical and numerical methodologies to estimate the optimal range for c. Through comprehensive numerical experiments, we investigate the impact of different values of c on the algorithm's convergence behavior and computational efficiency. Comparative analyses are conducted between GDSHS variants with varying c values and established conjugate gradient methods such as Fletcher-Reeves (FR) and Polak-Ribière-Polyak (PRP⁺). Our findings underscore the significance of setting c =1, which significantly enhances the GDSHS algorithm's convergence properties and computational performance, positioning it as a competitive choice among state-of-the-art optimization techniques.

A numerical solution by the finite element method of a homogeneous Dirichlet boundary value problem for an elliptic equation is examined (using a Poisson equation as an example) in a two-dimensional convex polygonal domain Ω with a singular right-hand side given by the Dirac delta function. A theorem on the existence and uniqueness of a generalized solution in the fractional Sobolev space H^s(Ω), 1/2 < s < 1, is proved. An approach to discrete analysis of the problem using the finite element method is proposed and investigated. The results of numerical experiments for a model problem, obtained using the FreeFem++ software, are presented. They confirm the error estimate of the difference between the discrete and exact solutions derived in the paper.

An emerging field of study is the application of fractional calculus to iteratively solve nonlinear equations. Recently, several Newton-type techniques have been proposed that make use of the notion of fractional order derivatives. However, the existence of at least first order derivative is essentially required for the convergence of these methods. On the contrary, we propose a new secant-type method which is inherently derivative-free, although its construction is based on the idea of conformable fractional derivative of order α ∈ (0,1]. The primary objective for the development is to analyze how fractional derivatives have an effect of enlarging the convergence domain. In this regard, the proposed scheme is examined for its convergence characteristics and dynamical features for different values of α in the specified range. Furthermore, the efficacy of the method is demonstrated through solving various applied nonlinear problems including the fractional order Burgers' equation.

In this paper, we will give a new Crank-Nicolson mixed covolume method for parabolic optimal control problems. The state and co-state variables are approximated by the lowest order Raviart-Thomas element and the control variable is approximated by piecewise constant function, while Crank-Nicolson scheme is ultilized for temporal discretization. We derive the priori error estimates for the control variable, the state and the co-state variables.

The aim of this paper is to derive efficient numerical algorithms for the numerical solution of nonstiff ordinary differential equations by applying the Richardson extrapolation technique to a class of explicit two-derivative Runge-Kutta methods. Theoretical results illustrate that the application of this technique has considerable impact on the accuracy and stability properties of the underlying numerical methods. The achieved improvements of the proposed algorithms are also confirmed by the results of some numerical experiments.

The problem of viscous oxide films, which prevent the full release of energy from boron powder during combustion, was overcome using graphene fluoride (fluorographene). This chemical compound was chosen due to its high fluorine content, low hydrogen content, low surface free energy, and strong thermal conductivity. Graphene fluoride reacts with boron, releasing a large amount of heat and gaseous products during combustion, effectively removing the viscous oxide film, and preventing boron agglomeration. Graphene fluoride was synthesized by shear cutting in an emulsifier, and graphene fluoride-boron composites were fabricated by solvent evaporation. Thermal analysis and heat of combustion tests showed that the prepared thin graphene fluoride layer had an average thickness of 1.56 nm. A composite of 20% graphene fluoride and boron showed a 1.86-fold increase in heat of combustion. Moreover, the addition of 20% graphene fluoride effectively improved the heat release during combustion of boron powder, making it comparable to the heat release during combustion of high-energy composites consisting of metal and boron powders.

The results of numerical modeling of cellular detonation propagation in inhomogeneous gas suspensions of aluminum particles in a hydrogen-air mixture are presented. A physical and mathematical model of hybrid detonation is used, describing chemical reactions within the framework of the given kinetics. The model takes into account homogeneous and heterogeneous reactions with the formation of suboxides or solid aluminum oxide particles, as well as phase transitions (evaporation and decomposition of the oxide) in the reaction products. The model is consistent with known experimental data and the results of thermodynamic calculations of detonation parameters and mixture composition at equilibrium. Flows in channels with transverse gradients and discontinuities in particle concentrations are considered. Various patterns of cellular structures are obtained, allowing us to consider the spatial distribution of particles as a controlling factor in detonation processes.

Experiments show that preheating the shaped charge liner improves its penetrating power. This increase is due to the increased ultimate elongation of the formed shaped charge jet due to thermal softening of its material. The possibility of heating the jet itself in free flight by thermal radiation from a tube located in front of the shaped charge, with heat generation within it caused by a chemical reaction of self-propagating high-temperature fusion, is considered. The characteristics of shaped charge jet heating by thermal radiation are investigated using an analytical solution to a one-dimensional axisymmetric problem of unsteady heat conduction for a uniformly elongating cylindrical rod. It is shown that before plastic breakdown of copper shaped charge jets occurs, they can be radiantly heated in free flight to a temperature that allows for a slight increase in the jet's penetrating power.

Impact tests of 1565 aluminum alloy in the impactor velocity range of 242-653.7 m/s revealed that at a certain impactor velocity (626 m/s), a sharp increase in particle velocity occurs in localized regions of the target. Microstructural studies of the sample revealed traces of localized deformation. Simultaneously, material is ejected from the rear surface of the target. This phenomenon correlates with the stochastic behavior of strain carriers at the mesoscopic scale-the presence of mesoparticle velocity dispersion. To account for the influence of stochasticity on shock wave propagation, a system of equations from the continuum theory of dislocations is used, which includes a dislocation velocity distribution function. It is shown that local attenuation or acceleration of the shock wave is determined by the relationship between velocity dispersion and the flow velocity of the dislocations.

The stress-strain research of rock mass is carried out, with verification by observations over underground openings at the Starobin and Petrikov deposits of potassium salt. The qualitative and quantitative indicators of the limit state zones in the vicinity of mine openings at moderate and great depths were compared using an integrated criterion. The formulas are proposed for determining sizes of limit state zones at great depths, with regard to geological structure of the test deposits. The numerical modeling algorithm of formation of rock blocks in the vicinity of underground openings on the basis of introduction of special block elements as systems of elastic and viscoelastic links is discussed. The research findings are applicable in stability assessment of mine openings in planning mining operations, and in selection of mine support and protection methods.

The article presents the ground surface deformation monitoring data for a 40 years-long period. The space and time parameters of geodynamic movements are revealed from the analysis of long-term observation over ground movements. The ground movement data base is created for the classification, modeling and estimation of ground movements, and for the analytical definition of patterns in big data arrays. The statistical and wavelet analyses of rates of change in vertical displacements of ground surface are performed. The ground surface zoning is carried out at the Sarany chromite deposits and in the adjacent areas with a town and industrial facilities. The results are useful for the detection of unknown parameters of geodynamic processes on ground surface, and for the prevention of accidents connected with instability of capital facilities during underground mining.

The estimation procedure of a displacement zone at a mined-out void filled with cemented paste backfill in mining of kimberlite deposits of ALROSA is described. The applicability of numerical stress-strain modeling and established normative standards is demonstrated. The deficiency of the current methods and norms in delimitation of hazardous displacement zones is identified. The proposed solutions conform with the actual conditions of the Internatsionalny and Aikhal Kimberlite Mines. Localization of a hazardous deformation zone nearby a mined-out area is demonstrated as a case-study of underground mining with cemented paste backfill in the Mir-Gluboky Mine. The displacement zone parameters at the Mir-Gluboky Mine are calculated.

The article addresses seismic activity induced and triggered by iron ore mining in Gornaya Shoria. In 2024 in the populated areas of Sheregesh and Tashtagol, perceptible earthquakes with local magnitudes 4.5 and 4.6 took place, respectively. A partial synchronization effect in seismic activity was revealed in the area of three mines, namely, Tashtagol, Sheregesh and Kaz, with simultaneous amplification of seismicity over a period from 2012 and to the present day. Seismic activity is spasmodic, with periodic attenuation both in terms of energy and number of seismic events, and with the subsequent recommencement. The energy of seismic activation events correlates with the mining rate and steadily rises as the latter grows.

The authors have developed the method of adapting blast designs and patterns to structurally complex mineral deposits on the basis of synthesis of theory of zonal rock fracture and theory of blast impulse. This article describes the sequence of practical adjustment of blast designs and patterns with regard to geological conditions. The method includes monitoring of rock mass, analysis of data, selection of techniques and their efficiency evaluation using an integral criterion embracing safety of blasting, quality of fragmentation and economic indicators. The authors propose classification of the techniques and their combinations, capable of reduction of seismic impact, flyrock and expenditure. Particular attention is given to the blast impulse peak pressure and duration control. The results enable adapting blast designs and patterns to nonuniform rock mass, and enhancing safety and efficiency of mining operations. The research prospects are connected with artificial intelligence technologies and digital data bases for forecasting blasting impact.

Coarse oversize fragments generated by blasting complicate loading and haulage of rocks, and this leads to the decreased productivity of labor and to the increased cost of mining. This article analyzes specific energy of roller-bit drilling as a drillability criterion as a case of the Koktaszhal deposit in Kazakhstan. Two electric drill rigs DML-1200 were additionally equipped with energy consumption recording facilities. The correlations between the powder factor, explosive fracture energy and ultimate compression strength of rocks, and between the average fragment and specific drilling energy are determined. For the blast design practice in open pit mining, it is substantiated to pass from mechanical specific energy of drilling to specific energy of explosive fracture and, further, to prediction of an average fragment of blasted rock. The experimental blasting operations at the Koktaszhal open pit mine show positive results which open prospects for the further research.

The authors discuss a variant of shrinkage stoping in mining steeply-dipping ore bodies of limited thickness. In the context of the majority of operating mines in Russia, numerical stress-strain modeling of gravitational stress state of an ore-rock mass is performed. The stress patterns in structural elements of the discussed geotechnology are determined as function of thickness and occurrence of the ore body, and subject to the technology implementation. It is found that rock mass quality greatly influences stability of different-purpose mine openings and ore pillars. The safe mining system parameters are determined and standardized for the typical geological and geomechanical conditions of the test deposits.

The geomechanical substantiation is provided for the technology of sublevel caving in mining close-spaced ore bodies with dirt parting of a varying thickness. The parametric model of sublevel caving includes the case of maximum advance of stoping front on sublevels. The computational patterns of maximum principal and shear stresses, as well as their concentration and relaxation in the main constituents of the mining system are obtained. The rock mass areas around various exposures, including preparatory and development openings, which are most susceptible to failure in case of complex tectonics, are identified. The analysis of different depths of driving fringe drifts and a decline in hanging wall of an ore body in depth of mining proves consistency of the adopted engineering solutions and safety of mining in varying geological and geotechnical conditions for the whole period of operation. The order and sequence of extraction of close-spaced ore bodies are validated to ensure caving of enclosing rocks toward mined-out void at the proper ground control. The parameters of underhand sublevel stoping, such that ensure safety and efficiency of mineral mining, are determined.

The authors obtained an analytical time law of freeze pipe temperature which ensures the constant thickness of a frozen wall at the stage of passive freezing. The time law is established using the equation of balance of heat flows at the phase interface. The correctness of the mathematical expression is proved by numerical modeling of freezing of a siltstone layer typical of conditions of shaft sinking in potash mines. The results are applicable in planning energy-efficient operating regimes of freeze pipes during passive freezing.

Climate changes in permafrost regions lead to noticeable alteration of the environmental conditions, including, in particular, an increase in permafrost temperature and depth of seasonal thaw and an activation of exogenous cryogenic processes. This paper presents the results of monitoring the active layer thickness and vertical surface displacements at the Circumpolar Active Layer Monitoring (CALM) site Lavrentiya located in the area of the “Eastern Chukotka Coastal Plains” research station. Under conditions of the increased summer heat supply over the period of 2004-2024, the rate of ground surface subsidence varied from 1.4 to 3.5 cm/yr, while changes in the active layer thickness (ALT) were from -3.2 to +1.6 cm/yr. The ground surface subsidence took place due to the isotropic thawing of the ice-rich transient layer of the soil-permafrost complex without the formation of thermokarst landforms. Thus, against the background of relatively stable variations in the ALT, a gradual unidirectional subsidence of the surface caused by the progressive thawing of the transient and intermediate layers was observed. The results highlight a significant underestimation of the rates of permafrost table deepening obtained by the traditional mechanical probing method.

The results of experimental studies of the influence of the initial freezing conditions and heating-cooling cycles of a finely dispersed model soil (kaolinite clay in a fully water-saturated state with the moisture content of 0.43-0.51) on its water filtration properties in the frozen state are presented. The filtration capacity of frozen kaolinite clay depends not only on its temperature but also on the freezing conditions. Graphs of the water permeability coefficient of the frozen soil versus temperature in the range of -0.05…-0.3 °C have been obtained for various soil freezing conditions. These graphs demonstrate the significant influence of freezing conditions on the filtration properties of frozen soil. Experimental research in this area is important for predicting the behavior of frozen heavy-textured soils near the initial freezing temperature, which is especially relevant in a changing climate.

Landscape-hydrological and hydrogeological changes have been studied in a second-order creek valley with water recharge taliks formed along two linear faults and an isometric depression closing the lower fault. A hypothesis about the tectonic origin of these changes is advanced based on the analysis of aerospace materials, in situ observations, and reference data. At least until 1965, there was no runoff in the valley downstream of the depression, and the maximum water infiltration rate exceeded 4 m³/s. Surface water infiltration, together with the deposition of sediment load, took place mainly in the depression. Subsequently, both processes virtually stopped there because of the rise of the bottom of the depression relative to the valley thalweg, and a fully developed channel was shaped downstream. Surface water infiltration has decreased by more than an order of magnitude and is observed now mainly in the area of linear faults. In the depression, it occurs sporadically at its margin, where a tectonic ditch is perpendicular to the creek channel. The ongoing tectonic activity may cause high intensity of water intake, up to the spontaneous discharge of the channel flow. In the observed case, such a discharge flow developed in the channel in the direction opposite to the slope of the creek thalweg. Such spontaneous phenomena cannot be explained within the framework of modern concepts about the minimum size of mobile tectonic blocks and attest to the need for their revision.

A design and technological solution to modify the soil temperature regime and maintain the upper boundary of permafrost in the roadbed at the required depth was developed. The main causes of road failure in permafrost regions were identified. The effect of water accumulated at the base of the roadbed on the temporal variation of the inclined permafrost table depending on the road slope was studied using numerical modeling. Numerical modeling was used to select the key geometric parameters of the design and technological solution controlling the temperature variation of the foundation soils. Regression equations describing the temporal variation of the slope of permafrost table in the roadbed were obtained using the mathematical planning of the experiment.

Icing formation represents a hazardous engineering-geological process that adversely affects infrastructure facilities. To predict icing development and suggest adequate control measures, it is necessary to identify the location of the icing water source and plan the placement of water intake wells. Geophysical methods help solve these tasks. The objective of this study was to investigate the structure of the groundwater discharge zone feeding a hydrogeogenic icing to plan anti-icing measures. The investigations employed ground-penetrating radar (GPR) equipped with an OKO-3 system and a 250 MHz antenna, capacitive-coupled resistivity measurements using VEGA instrument at 16.5 kHz frequency, and electrical resistivity tomography with induced polarization measurements using Skala-64k15 system. GPR data revealed that the seasonal freezing depth within the icing mound reaches 1.8-2.7 m. Signs of groundwater discharge were identified as local anomalies with reduced seasonal freezing depth down to 1.3 m. The study established that the icing mound forms over a seasonal frost heave mound containing an ice core, while the bedrock base shows evidence of a fault zone. Electrical resistivity tomography surveys and 3D modeling of resistivity and normalized chargeability distributions to a depth of 100 m enabled the identification and delineation of branching vertical channels of ascending groundwater filtration. These channels form a group source feeding the icing.

On August 8, 2025, Igor Vladimirovich Klimovsky, a senior researcher at the Melnikov Permafrost Institute, Candidate of Geographical Sciences, Honored Worker of the Economy of the Republic of Sakha (Yakutia), Veteran of Labor, and Honored Veteran of the Siberian Branch of the Russian Academy of Sciences, passed away at the age of 90. He will be remembered as a remarkable permafrost researcher committed to geocryological science, a tireless explorer, and an excellent field worker.