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The use of stage-wise schemes in the development of deep quarries is one of the ways to increase the economic efficiency of mining a deposit and determining the optimal stage parameters remains an urgent task. Such parameters are stage depth, bench height, block length, etc. However, there is a wide range of values for these parameters. Therefore, to select the optimal values and evaluate the effectiveness of design solutions, it is advisable to use the net present value, which is an international notion. As a result of the analysis of data on deposits, a large number of variable indicators can be identified that presumably affect the efficiency of mining. The article proposes to divide all parameters of the quarry mining into two types: mine engineering and economic. The importance of each of them is determined by the measure of influence on the net present value. Thus, to assess the measure of influence of mining indicators, the average values of each of them are taken, and as a result of the alternating change of one parameter under study, the measure of its influence on the discounted income received is estimated. The results of the analysis of relevant factors, their evaluation and comparative analysis are important indicators that significantly affect the design decisions made and the effectiveness of the investment project.

The article reports on the presence of minerals of the crichtonite group (MCG) in ooids of mineralized volcaniclastic rocks of the Rudnogorskoe iron deposit (Eastern Siberia). The ooids are characterized by a concentric-zoned structure of detrital component, expressed in a sequential change of hematite-smectite core → smectite-chlorite → chlorite-garnet → apatite-chlorite zones, which are rimmed by thin-layered magnetite. Rare crystalline MCG aggregates in ooids are found in the peripheral apatite-chlorite zone. Based on the chemical composition and Raman spectra, the MCG are identified as crichtonite and davidite-Ce. The following components are determined in the composition of crichtonite, wt.%: TiO2 63.73-70.69, FeO 18.03-23.58, SrO 2.24-4.03, CaO 2.22-4.10, MgO 0.33-1.02, Al2O3 up to 2.01, MnO up to 0.54 and Ce2O3 up to 1.88. Davidite-Ce typically occurs along the edges of crichtonite and contains, wt.%: TiO2 60.54-62.28, FeO 22.67-25.77, Ce2O3 3.18-5.0, La2O3 2.47-2.74 and SrO 0.58-0.64. The MCG also contain up to 4.69 wt.% UO2. Complex processes of breakdown of MCG and their replacement by anatase are accompanied by the formation of REE (anzaite-Ce) and U (uraninite) minerals and subsequent transformation of anatase to rutile. A sequence of mineral formation of the ooids indicates that the formation and growth of the MCG crystals is a result of lithification of accumulated Ti and trace elements during smectitization of basaltic clasts. Further processes of mineral transformation are associated with the transformation of crichtonite to simple Ti oxides and the precipitation of REE and U minerals. Titanite is a product of the final skarn stages of ore formation.

A new model of an integrated economic system is investigated which consists of two markets – raw materials and products interconnected by selling and processing raw materials into products. When the markets reach an equilibrium state, this model allows estimating the commodity flows and the economic efficiency of each producer of raw materials or products taking into account the market conditions. With such a structure of interconnected commodity markets, producers in the raw materials market are buyers of raw materials, and in the products market – sellers. Due to this feature of the market system the demand function for raw materials is set implicitly, and the standard methods for searching the equilibrium seem ineffective for this problem. In order to find an equilibrium state for the presented structure of interconnected commodity markets, an algorithm for searching the Nash equilibrium was developed, which takes into account the desire of each market player to maximize profits considering the market conditions and the behaviour of competitors. By applying the methods of game theory and economic modelling, this research provides insight into competitive dynamics and strategic interactions both between players within a single commodity market in terms of competition, and between the markets proper in terms of formation of interconnected pricing. The results have practical significance for developing the market and investment strategies for the companies from real sectors of economy, production modernization programs, and optimization of government subsidy programs.

Subsurface use waste accounts for the overwhelming majority of waste generated and accumulated in Russia. The increase in the volume of processing of minerals by the mining and processing industries leads to an aggravation of environmental problems – the negative impact of overburden dumps, tailings of enrichment and processing of mineral raw materials on the environment is increasing. Using the example of three types of rocks, the possibility of using carbonate subsurface use waste as raw materials in the formation of photocatalytic composite materials (PCM) in the production of building materials and products, and simultaneously solving environmental problems of territories through large-scale utilization of man-made waste, is considered. A complex of physical (porosity, specific surface area, dispersion, surface morphology) and chemical (chemical composition, acid-base centers, zeta potential, hydrogen index) studies of the properties of carbonate materials of various genetic types have been carried out to determine the possibility of their use as a substrate in the production of PCM. The photocatalytic material obtained by depositing sol-gel synthesized titanium compounds onto a mineral carrier is intended for incorporation into cement building composites and for giving them self-cleaning properties during operation. The mineral powders of limestone from the Tyushevskoye (T) and Porechenskoye (P) deposits and marble from the Polotskoye deposit were ranked according to certain requirements – dispersion, porosity, and adsorption activity. The establishment of numerical indicators for each type of raw material made it possible to determine the degree of suitability of mineral powders of carbonate rocks for the production of composite materials introduced into the composition of building materials. A ranking of mineral powders was carried out to increase the potential efficiency of use in the composition of PCM in the following sequence: limestone T → limestone P → marble. PCM based on carbonate carriers exhibit high rates of organic pollutant degradation (more than 90 %) and are applicable as photocatalytic agents.

A comprehensive study of the evolutionary history of the Marun-Keu complex in the Polar Urals is presented. Utilizing both original data and published earlier information, this work establishes the temperature and pressure ranges corresponding to the magmatic and metamorphic stages of rock evolution, as well as estimates the geothermal gradient and continental crust thickness. Thermobarometric calculations for the magmatic stage were performed using machine learning techniques, specifically the “random forest” algorithm, based on experimental datasets and require minimal petrochemical input regarding rock composition. The pressure-temperature (PT) conditions of the metamorphic stage were evaluated using the THERIAK-DOMINO software package. The host rocks of the eclogites are interpreted as products of partial melting of continental crust induced by interaction with heated basic-ultramafic melts. Peak metamorphic pressures for the eclogites are estimated not to have exceeded approximately 21 kbar, with corresponding temperatures ranging 730-750 °C. Subsequent retrograde metamorphism within the Marun-Keu eclogites was constrained to temperatures below 640 °C and pressures above 5 kbar. The geothermal gradient during protolith formation of the eclogites was calculated to be approximately 13 °C/km, consistent with contemporary estimates for continental crustal settings. Furthermore, the subduction parameters were inferred, yielding an estimated slab dip angle of 6-8°, and a subduction velocity between 2.2 and 2.9 cm/year, which does not contradict the hypothesis of continental subduction.

The paper presents the results of geological, geochemical and isotope geochronological studies of Early-Middle Devonian volcanogenic-sedimentary strata of the NW Rudny Altai, which host Devonian VMS-type (volcanogenic massive sulphide) deposits. The study provides a solution to the problems of identification and correlation of volcanic formations, study of their structural and lithological-facial features, which is traditionally a necessary element in the reconstruction of ore-magmatic systems. The aim of the study is to reconstruct the volcanic sequence in the Early-Middle Devonian and to evaluate the contribution of volcanogenic formations of riftogenic and supra-subduction nature to which VMS-type deposits are genetically related. Isotopic U-Pb dating of zircons from representative tuffs is consistent with an age of ~390 Ma. The formation of the volcanogenic strata occurred in a tectonic setting associated with the opening of the sea basin, corresponding to the initial stage of riftogenesis in the Rudny Altai. In terms of geochemical characteristics, the rocks of the lower section are similar to those of the ensialic arcs. The petrogenesis of such magmas should be associated with fluid-saturated conditions of partial melting of crustal substrates and under the control of dehydration of the subducting plate. In the upper section, the volcanic rocks are geochemically similar to bimodal formations from riftogenic settings behind the ensialic arc. This is confirmed by analyses of the genetic type of the formation community (magmatic, sedimentary and ore-bearing) and is consistent with the geochemical type of the volcanic rocks, which is similar to that of riftogenic settings. The conceptual geodynamic scenario corresponds to the formation of the Rudny Altai ore deposits in the transition zone between the island-arc and the back-arc basin, similar to the riftogenic settings of the Eastern Asian margin.

Monitoring of the stability of technogenic objects is a critical aspect of ensuring safety and preventing emergencies caused by mining and geological processes. The integrated use of various monitoring methods allows obtaining comprehensive information on the dynamics of deformation processes. The complex system of geotechnical monitoring of technogenic objects on the basis of geospatial data was developed, which was tested in the conditions of the “Edelweiss +” open-pit coal mine (Republic of Kazakhstan). The system was based on the step-by-step integration of Earth remote sensing methods, satellite radar interferometry, aerial photography with the use of unmanned aerial vehicles (UAVs), as well as modern instrumental methods – electronic tacheometry and GNSS measurements. The first stage – analysis of archive satellite images to identify areas of significant surface displacements. The second stage is aerial photography using UAVs to create detailed 3D models of surface areas with deformations. The third stage includes the creation of a geomechanical monitoring system based on instrumental observation methods in areas with critical changes. The final stage is the creation and updating of a geospatial database that provides continuous monitoring of the object’s condition. As a result of testing of the geotechnical monitoring system based on Sentinel-1 and TerraSAR-X/TanDEM-X satellite images, surface subsidence of up to 25 mm was detected on the northern side of the “Edelweiss +” open-pit mine. Aerial photography of the open-pit mine allowed us to construct digital 3D models of the terrain, the comparison of which confirmed deformation processes at the +556 m horizon. Instrumental observations using modern geodetic methods clarified the type and dynamics of deformations of the rock mass. Integration of geospatial data in the geotechnical monitoring system ensures prompt detection of deformations, their analysis and forecast, which allows us to minimize the risks of destruction and increase the safety of operation of technogenic objects.

The lithological features of the Middle Cambrian sublittoral-littoral deposits of the Lower Evenki Member (Baykit Anteclise) have been refined. Four types of dolomites are identified: with stromatolitic texture, clotted-peloidal, replacement crystalline without preservation of the protolith primary structures, and replacement variably-crystalline with relict silt-pelitic structure. Post-sedimentary alterations of the rocks are associated with multi-stage dolomitization processes – early, syngenetic (in dolomite with stromatolitic texture and/or bacterial structures) and later (in replacement dolomites and silt-sandstones with dolomitic cement). The isotopic composition of carbon and oxygen in carbonates is analyzed. The elemental composition of carbonate, terrigenous-carbonate, carbonate-terrigenous, and terrigenous rocks is studied. A heat map with clustering was used to visualize the general pattern of enrichment by various elements. Carbonate lithology types are significantly enriched in Co, Cr, Sc, Rb and depleted in Cu, Zn, Li, Ba, Pb, and Sr in comparison with carbonate Clarke values. The nature of the positive Eu anomaly is investigated; its origin is attributed to Eu-bearing minerals in the terrigenous component of the rocks, rather than to hydrothermal solutions. No direct correlation is observed between the Rare Earth Element (REE) content and the amount of terrigenous admixture, thus the influence of reducing conditions or the composition of the dolomitizing fluid on the REE distribution cannot be ruled out. Terrigenous varieties are depleted in Cu, Zn, Pb, Ba, Th, U relative to the Clarke values for clays and clay shales. When normalized to PAAS, dolomitic argillites, dolomitic siltstones, sandstones, and silt-sandstones generally show enrichment in HREE relative to LREE. The source of the terrigenous clastic material was the Precambrian terranes of the Yenisei Ridge, formed by island-arc complexes, and recycled sedimentary material.

The Arctic shelf zone is an important research target due to its significant hydrocarbon potential. A study of the physical properties (density, elasticity, elastic anisotropy index, specific acoustic impedance, and porosity) was conducted for core samples from six wells in the South Barents Basin: Admiralteyskaya-1, Krestovaya-1, Ludlovskaya-1, Shtokmanskaya-1, Arkticheskaya-1, and Severo-Kildinskaya-82. The sample collection consists of sandstones, siltstones, and limestones. Core analysis revealed that rocks from non-productive wells (Arkticheskaya-1, Admiralteyskaya-1, and Krestovaya-1), located in the central part of the South Barents Basin and within the Admiralty High, differ in their physical and petrographic properties from rocks in gas and gas-condensate wells (Shtokmanskaya-1, Severo-Kildinskaya-82, and Ludlovskaya-1), located near the boundaries of the South Barents Basin. Core samples from productive wells (Shtokmanskaya-1, Severo-Kildinskaya-82, Ludlovskaya-1) exhibit lower average P-wave velocities, lower specific acoustic impedance, and higher open porosity and/or elastic anisotropy index compared to non-productive wells (Arkticheskaya-1, Admiralteyskaya-1, Krestovaya-1). This combination of petrophysical parameters provides the reservoir properties of rocks prospective for hydrocarbons. The petrographic variation of the reservoir properties of the studied rocks from productive to non-productive wells is associated with a decrease in grain size and a transition from pore-filling cement to thin-film and basal cement. The sandstones from the Shtokmanskaya well have a larger grain size (0.1-0.5 mm), whereas the sandstones from the Arkticheskaya-1 and Krestovaya-1 wells are finer-grained (0.1-0.2 mm). The Shtokmanskaya-1 well is characterized by pore-filling cement, the Arkticheskaya-1 ‒ by thin-film cement, and the Krestovaya-1 ‒ by cement of the basal type. The established physical properties of sedimentary rocks, suitable for the development of productive strata, will allow for the screening out of empty areas at the preliminary stage of analyzing geophysical materials during the search for geological and tectonic structures prospective for hydrocarbon accumulations.

Changes in the business conditions of gas industry enterprises and the regulatory framework for the creation and operation of energy facilities require the development of the energy infrastructure of production facilities. The diversity and a large number of existing energy facilities, as well as the use of a risk-oriented approach to the gas industry management lead to the need to create decision support systems for the strategic development of the energy infrastructure of production facilities on an industry-wide scale. The purpose of the study is to develop a set of mathematical models for calculating the index of the technical condition of energy complexes of production facilities used to prepare structured information as a part of a decision support system creation for the strategic development of the system, which will allow us making a decision on the minimum required volume and timing of reconstruction of the energy infrastructure of a production facility under modern conditions with restrictions on the reconstruction budget. The solution of such a multi-criteria problem required: justification of a set of admissible solution alternatives, risk assessment when making specific decisions, development of a system and mathematical dependencies for assessing the criterion indicators that make up the technical condition index taking into account preferences and decision rules, as well as the rules for calculating the weight of the assessment components in the value of the integral indicator. Based on the developed mathematical models, an algorithm for the technical condition index determination of a single energy complex of a production facility was formulated, which is an integral part of the generalized algorithm for applying the mathematical support of the decision-making system for the strategic development of the energy infrastructure of gas industry enterprises.

Groundwater is one of the key natural resources, so maintaining its high quality is one of the main problems in mining. The aim of the article is to study the dynamics of the level and hydrochemical regime of groundwater in the influence zone of apatite-nepheline ore mining in the southeastern part of the Khibiny alkaline mountain massif. Over the 10-year history of the Oleniy Ruchey Mining and Processing Plant of North-West Phosphorous Company JSC, significant changes in the chemical composition of the studied groundwater of the aquifers of the Upper Quaternary Ostashkov fluvioglacial horizon f,lgQIIIos and Paleozoic intrusions yPz have occurred. The content of the main ions in groundwater increased from 2 to 20 times, nitrates up to 50 times (exceeding the maximum permissible concentrations of 45 mg/l), and NO^–₃ entered the category of the main ions of groundwater. The source of the main ions and the increase in mineralization in groundwater is the weathering and leaching of the main ore minerals – apatite and its varieties, nepheline, sulphide minerals, as well as the use of explosives containing nitrogen compounds. As a result of this hydrochemical evolution of groundwater, the ratio of the main ions has changed – natural water of hydrocarbonate-sodium composition with neutral pH values has now become hydrocarbonate-calcium, NO^–₃ are in the second place among anions, and Na+– among cations. In the hydrodynamic regime of groundwater at the Oleniy Ruchey deposit, spring and autumn maximums of groundwater levels are clearly expressed. During a decrease in the level, contaminated more mineralized mine waters are drawn to the wells, and during an increase in the level, low-mineralized waters of atmospheric precipitation infiltrate into the aquifers. A decrease in average annual groundwater levels has been established, which is associated with an increase in the quarry depth and the water intake of groundwater for water supply to the mine.

This study investigates unique weathering crust samples from the most altered sections (30-43 m) of the weathering profile within the Souktal Plutonic Complex, Northern Kazakhstan. The samples, obtained from two drill cores, consist of quartz, kaolinite, microcline, muscovite, and plagioclase, as identified through polarized light microscopy and confirmed by X-ray diffraction analysis. Sequential extraction of rare earth elements (REE) was performed using inductively coupled plasma mass spectrometry (ICP-MS) following a two-step leaching procedure with hydroxylamine hydrochloride (0.2 mol NH₂OH·HCl) and sodium hydroxide (1 mol NaOH) solutions. The extraction process effectively recovered REE, indicating their presence in an ion-exchangeable form, with total extraction rates (REE + Sc + Y) ranging from 4.1 to 7.8 ppm. The total light REE content varies from 3.5 to 5.9 ppm, while heavy REE content ranges from 0.2 to 0.7 ppm across all samples. Petrological and geochemical analyses suggest that the studied area represents an ion-adsorption-type REE weathered deposit. These findings enhance the understanding of ionic-adsorbed REE within weathering crusts and highlight the effectiveness of sequential extraction methods for REE determination. Moreover, the study suggests that this area holds promising potential as a future REE ion-adsorption site, contributing to the development of Kazakhstan’s national REE industry.

The article is devoted to the actively developing area of wastewater treatment – Constructed Floating Wetlands (CFW, floating bioplatforms). The paper explores the creation history and operational experience of CFW in Russia and abroad. It describes the designs and preferred compositions of substrates and plants for creating phytomodules, paying special attention to the use of natural minerals and the selection of local macrophyte plant species. The CFW technology is suitable for treating various types of wastewater, including inorganic effluents from mining enterprises. The research examines the results of applying phytotechnology for wastewater treatment for pollutants (total nitrogen and phosphorus, organic matter, suspended particles, heavy metals, sulphates, boron, etc.). The article shows successful practices of using CFW for acidic drainage effluents, which are the most challenging for phytotechnology application. The study identifies key factors affecting pollutant removal efficiency – water depth, flow rate, coverage area, aeration, and temperature. The research presents methods to enhance the depth of water treatment at low temperatures. It also notes the positive impact of floating bioplatforms on the condition of water bodies where they are located. The study provides cost estimates for applying CFW technology for wastewater treatment and gives recommendations based on the experience of implementing the technology at a settling pond of a mining enterprise in the Murmansk Region.

The article presents the results of a comprehensive study of diamondiferous lherzolite from the V.Grib kimberlite pipe. The composition of rock-forming minerals (olivine, orthopyroxene, Cr-diopside, Cr-pyrope) in terms of major elements mainly corresponds to minerals from inclusions in diamonds of the lherzolite association and diamondiferous lherzolites of the world. The elevated modal amount of orthopyroxene (18 vol.%) as well as the concentration of FeO (7.5 wt.%) and the value of MgO/SiO2 ratio (0.89) for lherzolite allow assigning it to orthopyroxene-enriched lherzolites. Specific features of the composition of Cr-diopside and Cr-pyrope in respect of rare elements indicate that at the time of capture by kimberlite, lherzolite retained the signs of a slight impact of mantle metasomatism. Modelling results allowed suggesting magnesiocarbonate and silicate high-density fluids (HDF) as the metasomatic agent. No signs of influence of proto-kimberlite melt were found. The degree of nitrogen aggregation in diamond (%B from 6 to 15) indicates a long stay in mantle conditions, which excludes formation shortly before the emplacement of kimberlite. Extremely light values of carbon isotope composition (δ13C = –18.59 ‰) indicate the involvement of organic carbon of subduction origin in diamond formation. Diamond formation could be associated with an ancient metasomatic event occurring with the leading role of low-Mg silicate-carbonate HDF, the source of which were eclogites and/or subducted sedimentary deposits containing organic carbon. The calculated P-T parameters (3.7 GPa, 814 °C) of the last equilibrium of mineral phases of lherzolite point to its capture from a depth of ~118 km, which corresponds to a section of the lithospheric mantle (approximately 95-120 km), within which rocks also demonstrating features of specific transformations under the influence of subduction-related fluids were earlier discovered.

The issue of reducing electricity consumption costs is becoming relevant for industrial enterprises, taking into account the growing demand for electricity every year. The electricity consumption of air coolers at a gas processing plant was considered in the framework of this study. The change in ambient temperature (during the day and depending on the season) is the main disturbing factor affecting the performance of air coolers. With such significant seasonal changes in air temperature, its density changes, which causes fluctuations in the power consumed by the electric motor by up to 30 %. The issues of increasing energy efficiency, forecasting and determining the power consumption rate of air coolers, depending on changing external conditions, therefore become important. A methodology has been developed to determine the standard power consumption of air coolers depending on two factors – the ambient temperature and the load of the gas processing plant. A two-factor power-law approximation of the values was carried out due to nonlinear dependencies on plant loading and ambient temperature. The dependence of power consumption on ambient temperature and the loading of the installation on raw materials for any type of air cooler is determined with high accuracy (the root-mean-square error of the calculated and approximating values does not exceed 1 %). The formula for calculating the standard consumption of electric power of the air cooler at the considered installation was determined based on the results of the study. The methodology can be used by employees of gas processing enterprises to determine the standard electricity consumption of air coolers under changing climatic and technological factors.