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The operation of oil production wells is accompanied by the invasion of well killing fluids into a near wellbore zone while well intervention which deteriorates rock permeability and decreases well oil rate. In order to restore the permeability of the rock in the near wellbore zone of the formation, it is proposed in this work to use ultrasonic alternating loading during well inflow stimulation. To study the effect of alternating loading on the permeability of rocks, a laboratory set-up is developed and filtration experiments are carried out. The rock studied was sandstone of medium permeability. The experimental studies included four stages: filtration of the killing fluid (calcium chloride solution) in the forward direction (simulating well killing); keeping the sample in conditions of pumped kill fluid; filtration of kerosene in the opposite direction (simulating an inflow stimulation) until the maximum possible restoration of permeability; filtration of kerosene in the reverse direction under ultrasonic alternating loading conditions for additional permeability restoration. It was revealed, that under conditions of ultrasonic alternating loading, the pore space of the rock, previously blocked by particles of the killing fluid, is unblocked and the permeability of the samples is restored. An analysis was made of the mechanism of blocking the pore space with the killing fluid and restoring the permeability of the rock.

When designing the parameters for the development of oil and gas field at significant depths, crucial to comprehend how certain factors affect the behavior of reservoir rocks and host rocks. These factors include the high level of rock stress, the ambient temperature field, and the hydro- and gas-dynamic processes within the mass. The impact of one or a combination of these factors can result in alterations to the construction, structure, composition, and properties of the rock mass and, ultimately leading to a mismatch between the design solutions and the actual conditions. The purpose of the research is to establish a methodology for conducting laboratory studies that investigate the impact of the mode of occurrence of oil and gas field reservoirs at great depths on the properties of rock samples. The research objectives encompass a theoretical analysis and the identification of the principal factors influencing rock behavior and changes in internal structure. Additionally, the objectives include developing laboratory research methods that comprehensively simulate these factors and conducting trial experiments to assess their effects. As part of the project, tests were conducted on sandstone samples collected from depth ranging from 3.5 to 4 km within the hydrocarbon field. These studies were performed while simulating thermobaric reservoir conditions, which include temperature, rock pressure, and reservoir pressure. The results of these experiments, aimed at examining the behavior of rock samples as closely as possible to their natural reservoir occurrence at depth of 3.5–4 km, are presented. It has been observed that rock samples of the same lithology, collected from nearly identical depths, can exhibit significant differences in deformation characteristics, both in the pre- and off-limit regions of loading. The findings from these studies provide the initial data for the development and refinement of geomechanical model behavior for materials that take into account not only fracture strength criteria but also dilatancy processes at various stages of rock deformation. Increasing lateral pressure within the range of 0 to to 55 MPa causes relatively minor change in ultrasonic vibration velocities, typically ranging from 1 to 10%. This makes it challenging to determine the necessity of utilizing these results for indirectly assessing changes in rock properties within the mass. Nevertheless, within the context of geophysical studies, considering variations in velocity values enhances the quality of result interpretation, especially given the substantial geometric dimensions of the rock masses under investigation. Research into the acoustic emissions of rocks in a complex stressed state enables the monitoring of spatial micro- and macrofracturing processes throughout the entire loading phase of samples. This provides a more comprehensive understanding of changes in their internal structure. The article delves into the factors that impact structural changes in oil and gas field rocks, particularly as their development extends to greater depths. The study outlines methodological approaches that facilitate the investigation of physical and mechanical properties of rock samples, while accurately modeling complex thermobaric conditions. Additionally, the it describes the technical specifications of the testing equipment, ensuring the closest possible replication of the actual conditions of reservoir rock occurrences. Lastly, the study reveals key features related to the deformation and fracture of rock samples during testing under lateral pressures of 55 MPa and pore pressures of 30 MPa, along with the creation of temperature fields up to 100 °C.

The research reveals that during selection of a method to increase oil recovery it is necessary to take into account rheological features of fluid movement through the formation, effect of capillary forces and heterogeneity of reservoir properties of the productive formation in thickness and along the bedding. Low-frequency wave impact, which is used to increase production in oil fields, is considered. At low-frequency impact new fractures appear and existing fractures in rocks increase in size. The greatest increase in porosity and permeability of rocks occurs at an impact frequency up to 10 Hz. Dynamics of oscillation amplitude during wave's movement in saturated porous medium is studied in the paper: essential attenuation of amplitude occurs at distance up to 1 m from borehole axis. With increase of frequency from 1 to 10 Hz the intensity of amplitude's attenuation decreases. The technology was tested on a well in Perm region (Russia). The actual permeability value was 50 % higher than the predicted value. According to the results of hydrodynamic investigations processing, it was noted that the greatest increase of permeability took place near the wellbore, while away from the wellbore axis permeability remained almost unchanged. In order to refine the mathematical model for prediction of wave impact on rock permeability it is necessary to take into account interconnection of pore space structure, change of adhesion layer, as well as to study transfer of particles during vibration.

Integral and differential approaches to determining the volumetric compression of rocks caused by changes in the stress state are considered. Changes in the volume of the pore space of rocks are analyzed with an increase in its all-round compression. Estimation of changes in the compressibility coefficients of reservoirs due to the development of fields is an urgent problem, since the spread in the values of compressibility factors reduces the adequacy of estimates of changes in the physical properties and subsidence of the earth's surface of developed fields and underground gas storages. This parameter is key in assessing the geodynamic consequences of the long-term development of hydrocarbon deposits and the operation of underground gas storage facilities. Approaches to the assessment differ in the use of cumulative (integral) or local (differential) changes in porosity with a change in effective pressure. It is shown that the coefficient of volumetric compressibility of pores calculated by the integral approach significantly exceeds its value calculated by the differential approach, which is due to the accumulative nature of pore compression with an increase in effective pressure. It is shown that the differential approach more accurately determines the value of the pore compressibility coefficient, since it takes into account in more detail the features of the change in effective pressure.

Water and environmental problems are caused by the systematic inflow of unsaturated drainage waters and low-mineralized brines into the mine No 2 of the Stebnyk potash deposit. Filling the mine workings with unsaturated brines caused the risk of losing the stability of the interchamber pillars and ceilings in the spent chambers, rock separation, intensification of karst-breaking processes. The paper analyzes the development of the ecological emergency in chronological terms. Hydrogeological, hydrochemical, seismic and geophysical data of monitoring, visual and instrumental observation of the deformation of the earth’s surface were used to solve the set tasks. The dynamics of flooding of the mine № 2 was analyzed. In the mining massif of mine No 2, the decompaction of rocks along the formation 10 in the Northern-Eastern direction towards the spent chamber 115 was recorded, the infiltration supply zone, the transportation zone and the groundwater discharge zone were established. The presence of intensive filtration of surface waters in the massif of rocks indicates the process of karst formation, which is confirmed by the inflow of formation waters into the mine workings and the decomposition of interchamber pillars. The zone of decompaction extends towards the mine, where the development of karst is maximum. The destruction of the inter-chamber columns and the ceiling led to a significant increase in the level of brine in the chambers of the second horizon at the end of 2014. It is estimated that the volume of broken pillars is ~ 473,540 m3. The correlation between the long uncontrolled growth of increase in the amount of unsaturated drainage water in the mining area in 1978-2013 and the formation of karst dips over the spent chambers of the first horizon was found. There was a breakthrough of supersalt low-mineralized aggressive waters to this horizon in October 1978.

The results of laboratory studies of nearly 1,300 samples from 50 wells of reservoirs of three productive terrigenous horizons represented by sandstones and siltstones are considered. Intergranular and fractured components mainly make up the porosity structure of reservoirs and their values influence the main parameters of rocks, including filtration-capacitive properties of reservoirs, and determine the processes of hydrocarbon field development. The spatial distribution of the intergranular and fractured components of reservoir porosity affects the development and exploitation of oil and gas reservoirs and determines the relevance of this study. The values of the fracture and intergranular component of porosity were determined by the author’s method using data on open porosity and the rate of elastic wave propagation in rock samples and the mineral skeleton of these samples during the simulation of reservoir conditions. A mosaic area distribution of fractured porosity values, caused by a long geological and tectonic history of the area development, was revealed. We identified zones of increased fractured porosity up to 0.7–0.8 % (percent absolute porosity) in the north and center of the western part of the field, and zones with minimum fractured porosity values of less than 0.2–0.3 % in the eastern part of the field. Results of laboratory core studies showed the presence of fractured porosity in reservoirs up to 1.26 %. The data on the size and distribution of fractured reservoirs across the Chayanda field area may be used to refine the field development project.

The composition creation of Liviu Stirbu is an example of organic interaction of the idioms of music of European professional tradition, national folklore as well as mass musical culture. The purpose of the authors of this article is to reveal the unique concept of Rhapsody for violin, cello and piano that emerged as a result of the interaction of music of academic tradition, on the one hand, and rock and jazz music, on the other. The influence of academic musical culture is found in using the genre features of scherzo, march and concerto, while the metro-rhythmic aspects of this opus are close to the phenomena of mass musical culture.

The authors develop a statistical method for determining the structures of rocks. A mathematically rigorous definition of the petrographic structure through the probabilities of binary intergranular contacts is proposed. The petrographic structure is defined as an invariant aspect of rock organization algebraically expressed by the canonical diagonal form of symmetric matrix of contact probabilities and visualized by structural indicatrices – 2nd order surfaces. A consistent nomenclature of petrographic structures has been proposed. Earlier the method showed itself well in describing the structures of ijolites and urtites of the Khibiny Mountains, as well as amphibolites of the islands of Keretsky Archipelago (the White Sea). Mass application of the method is restrained by the routine procedure of calculating the probabilities of intergranular contacts in petrographic thin sections under a microscope. The problem of modern optical structure analyzers is assignment different sections of the same anisotropic mineral to different minerals, and separation blocks of a mineral individual to different individuals. The paper describes the experience of using the domestic MIU-5M device for scanning petrographic thin sections by the linear method of Rosival. The combination of visual control and minimum automation of the process allows us to achieve convergence of the structural types with results obtained by manual processing of image of petrographic thin section. Additionally, thin sections have been studied, for which the structural types differ with various methods of counting. It has been revealed that the presence of poikilitic ingrowths and features of the mineral composition (the existence of hypergene changes or minerals with similar optical properties) affect the statistics of probabilities. Recommendations are given on the selection of the scanning step depending on the grain size in the studied rock.

The paper is devoted to studies of the volumetric response of rocks caused by changes in their stress state. Changes in the volume of fracture and intergranular components of the pore space based on measurements of the volume of pore fluid extruded from a rock sample with an increase in its all-round compression have been experimentally obtained and analyzed. Determination of the fracture and intergranular porosity components is based on the authors' earlier proposed method of their calculation using the values of longitudinal wave velocity and total porosity. The results of experimental and analytical studies of changes in porosity and its two components (intergranular and fractured) under the action of effective stresses are considered. This approach allowed the authors to estimate the magnitude of the range of changes in the volumetric compressibility of both intergranular pores and fractures in a representative collection of 37 samples of the Vendian-age sand reservoir of the Chayanda field. The method of separate estimation of the compressibility coefficients of fractures and intergranular pores is proposed, their values and dependence on the effective pressure are experimentally obtained. It is determined that the knowledge of the values of fracture and intergranular porosity volumetric compressibility will increase the reliability of estimates of changes in petrophysical parameters of oil and gas reservoirs caused by changes in the stress state during the development of hydrocarbon fields.

In addition to the standard description of the structures and textures of crystalline rocks the mathematical approaches have been proposed based on a rigorous determination of the petrographic structure through the probabilities of binary intergrain contacts. In general, the petrographic structure is defined as an invariant aspect of rock organization, algebraically expressed by the canonical diagonal form of the symmetric Pij matrix and geometrically visualized by structural indicatrices – surfaces of the 2nd order. The agreed nomenclature of possible petrographic structures for an n-mineral rock is simple: the symbol Snm means that there are exactly m positive numbers in the canonical diagonal form of the Pij matrix. New types of barycentric diagrams have been proposed. To describe the massive texture, the concept of Hardy – Weinberg equilibrium has been proposed. This boundary classifies barycentric diagrams into areas within which canonical types of Рij matrices and topological types of structural indicatrices are preserved. The change in the organization of the rock within a type is quantitative, the transition from one type to another means structural restructuring. The methods are used to describe ijolites and urtites of the Khibiny massif, the Kola Peninsula. In the modern taxonomy of rocks, the boundaries between them are mostly conditional and are drawn according to the contents of rock-forming minerals, for example, between ijolites and urtites – according to the contents of nepheline and pyroxene. The strict definition of the petrographic structure proposed by the authors makes it possible to introduce into petrography the constitutional principle (structure + composition), which is successfully acting in mineralogy.

The activity of the North-Eastern Shared Research Facilities of the Shilo North-East Interdisciplinary Scientific Research Institute, Far Eastern Branch of the Russian Academy of Sciences (NEISRI FEB RAS) is aimed at conducting analytical studies of rocks, minerals, ores, soils, lake and sea sediments, water bodies using various methods: optical microscopy, X-ray microanalysis, X-ray fluorescence analysis, quantitative emission spectral analysis, atomic absorption spectrometry, isotope geochronology, paleomagnetism and petromagnetism. The results of mineralogical, geochemical, petrophysical, isotope-geochronological (including radiocarbon) and palynological studies have been published in national and international scientific journals.

The article presents general information about the interdisciplinary Shared Research Facilities "Geoanalyst" of the Ural Branch of the Russian Academy of Sciences, the main directions of its work, analytical equipment and types of work that allow obtaining quantitative information on the chemical (elemental and isotopic) and phase composition, parameters of the crystal and electronic structure, type and concentration of the lattice defects, optical properties of samples including minerals, rocks, bottom sediments, ores, products of their enrichment and processing, natural and drinking water, as well as synthetic compounds, techno- and biogenic objects. Consideration is being given to the techniques involved in the Shared Research Facilities such as electron probe microanalysis and electron microscopy; X-ray fluorescence, atomic emission and atomic absorption analysis; X-ray structural and thermal analysis; microelement mass spectrometric analysis; isotope mass spectrometric analysis and geochronology; physics and spectroscopy of minerals. Emphasis has been placed on the fundamental and applied sciences based on the Shared Research Facilities, its scientific and educational activities and the experience of working with users. Details have been provided for the formulation, testing and use of microanalytical methods for in situ study of the composition, structure and properties of minerals-concentrators of transition, rare-earth and radioactive d- and f-elements (zircon, titanite, etc.) with a spatial resolution from units to tens of micrometers. There have been analyzed the application and development of research methods; their metrological parameters; the procedure for selection and certification of internal laboratory reference samples; the possibilities for solving problems of fundamental and applied physics and chemistry of mineral matter, as well as geochronological problems.

The paper describes a procedure for improving the approach to determining the ultimate strength of rock samples, the basic method is L. Prandtl’s method. In earlier works of the authors of this paper, the L. Prandtl’s method was improved in relation to rocks, using a general algebraic equation for calculating horizontal normal stresses depending on the vertical component and mechanical characteristics of the rock. Here, the authors reject the assumption that the tangent contact stresses resulting from L. Prandtl's solution do not depend on the abscissa x and on the variable vertical stresses, in contrast to the well-known Coulomb–Amonton law, according to which the tangent stresses are directly proportional to the vertical pressure. The regularities of contact normal and tangential stresses distribution at failure of prismatic samples are clarified. As result, the method was developed for calculating the tensile strength of samples with three characteristic values of mechanical properties: kп, yield strength of material in shear; ρ, angle of internal friction; fс, coefficient of contact friction. These characteristics can be established experimentally by simple experimental studies. The proposed approach is effective for constructing ultimate curves and diagrams of “stress — longitudinal strain” of rocks in the case of contact friction. A comparative evaluation is given for the proposed method for calculating the tensile strength of samples during their destruction with experimental data. Comparison of the calculated tensile strength with experimental data shows that the relative error of calculations according to the proposed method is significantly lower than the relative error of calculations performed using the E. Unksov’s method. The proposed method can be recommended for practical application.

Block-granular geological objects and rock volumetric mobility indicators are described. The mechanisms of structural and material reworking of rocks are considered in relation to the formation of a discrete tectonic structure of rocks and changes in the shapes of the geological bodies, which take place without rupturing the rock surfaces bounding these bodies and provide for the volumetric tectonic flow of solid rocks. Based on the study of natural objects and their comparison with the theoretical and experimental data on solid mechanics and geomechanics, it is suggested that one of the triggers for the volumetric disintegration of rock masses is rock fatigue damage (a fundamental phenomenon of solid-state physics). The disintegrated rocks behave according to the laws of mechanics of granular materials and mesomechanics. This study is of both theoretical and pragmatic importance as it contributes to the understanding of the regional geological features and provides new knowledge on the formation of crystalline protrusions known among the main hydrocarbon reservoirs within the basements of various geologic structures.

The relevance of the research is caused by the need to find the ways to increase the maximum depth of well drilling by the rotary-percussion method and its productivity. The main aim of the research is to establish the fact of growth of rotary-percussion drilling productivity through rising the mechanical speed of drilling while increasing the impact application eccentricity; determine the basic dependencies of the mechanical drilling speed and recess per one revolution as responses of the drilling system on the values of axial load, rotation frequency and eccentricity of impact application pulses; justify the expansion of the range of effective destruction of plastic rocks. Objects: mechanism of rock destruction by eccentric impact pulses. Methods: formulation and description of the experiment on rock destruction by eccentric impact pulses using the high-frequency hydrohammer HV-6 as a generator of eccentric impact pulses; measurement of empirical data obtained during the experiment; statistical processing of the obtained experimental data to establish the average values of the system responses; processing the data obtained by the method of a full factorial experiment, finding mathematical models of the mechanical drilling speed and recess per one revolution, depending on the values of the axial load and rotational speed and their graphical interpretation; analysis of the data obtained by empirical methods, formation of the main conclusions on the results of the study. Results. The authors have established the fact of increasing the productivity of the rotary-percussion drilling by determining the fact of mechanical drilling speed growth with rising eccentricity of the impact application in the range of 0–2 millimeters. The main dependences of the mechanical drilling speed and recess per one revolution on the values of axial load, rotation frequency and eccentricity of application of impact pulses were established.

The genre boundaries of modern music and literature have recently undergone significant changes that are connected with the appearance of a relatively new direction – rock music. A distinctive feature of this musical abstract is the presence of various sub-genre directions. One of these is folk rock music. The article presents an analysis of the meaning of mythonyms and theonyms in the cultural paradigm of folk music on the example of the work of the domestic folk-rock bands «The Melnitsa» and «The Nemnogo nervno». The process of studying the lyrics, reveals the correlation between the name of the text, represented by the mythonyms name, and the plot of the song in the context from which the mythonym (theonym) was borrowed. In the study the individual author’s transformation of the meaning of the myth is reflected and the religious and philosophical significance of onyms in the folk tradition is revealed.

The optimization of underground mining processes is carried out based on rational use of energy for obtaining preset broken ore size. The effective optimization requires correct assessment of the properties of the rock mass to be broken. Energy management requires assessment of rock mass stability decrease due to impact of natural and technogenic stresses. To make adjustments to the general energy management model, information on the rock mass structure is required to be obtained by geophysical methods. To optimize broken rock/ore size (to minimize oversized or excessively crushed mineral fraction yield during breaking), blasting energy application should be regulated and smart. The study is aimed at assessing the effectiveness of using geophysical methods for the prompt and correct assessment of rock and backfill mass condition during underground mining of mineral deposits. Decreasing stability of rock masses is assessed using the method of electrometric surveys in noncore exploratory boreholes. Rock mass stability study allowed revealing correlation and dependencies between the studied parameters. Effectiveness of using geophysical methods for differentiating natural and technogenic masses by degree of decreasing their stability due to geological and technogenic stresses. To determine the coefficient of decreasing rock mass stability based on rock apparent resistivity data, electrometric logging was used. This allowed to differentiate rock mass by the degree of decreasing rock mass stability based on the revealed dependency. The features of the geophysical survey components are described in details. The methodology and findings of the underground electric sounding using a sequential gradient electrode system at specific metal deposit are presented, including using theoretical curves and determining rock conductivity and the distance to workings. Besides, correctness of the geophysical method findings was assessed differentially. The assessment was prepared for decreasing rock mass stability based on electrometric logging data, and for advance outlining heterogeneity zones in rock masses by electric sounding along working walls. Based on findings of the conducted experimental work on revealing structural boundaries within rock mass, the method of electric sounding along working walls was recommended for application in practice. As for the studied borehole electric sounding application, the convergence of the experimental and theoretical curves is insufficient to recommend the method for practical application.

The relevance of the study is explained by the need to improve technological processes with the increasing complexity of the development of ore deposits with an increase in the depth of development, the use of powerful technology and an increase in stresses in arrays of ore-bearing rocks. The need to minimize the risk of mining requires the development and use of tools for managing an array. The purpose of this study is to systematize information about the theory and practice of using the residual bearing capacity of destroyed rocks from the practice of underground mining to improve the methods used to control the geomechanics of ore-bearing arrays. The complex of research includes analytical, full-scale, laboratory and theoretical methods that are used to identify the phenomenon of the use of the residual carrying capacity of destroyed rocks. To achieve this goal information on the use of bearing floors made of intact and destroyed ores and rocks, as well as other materials, is systematized. A brief description of the scientific support of mining engineering tasks is given. The phenomenon of the use of residual bearing capacity of disturbed rocks in the structure arising in the mountain massif is characterized. A critical analysis of the concepts of array management is given. Considered alternative options for creating structures for solving problems of reducing the health risk of workers and improving the quality of ores. A new typification of structures using the residual strength of destroyed rocks is given. It has been proved that in underground mining there is an opportunity to realize the residual bearing capacity of the destroyed rocks to create structures with desired properties, which contributes to solving the tasks of labor protection and improving the quality of ores.

Backfilling optimization is carried out through the use of discrete rock properties. A new line of the process improvement is based on the phenomenon of performance of residual rock strength when jamming in the process of underground mining of deposits within faulted rocks. The research is aimed at reducing costs of backfilling while ensuring the work safety. The goal is achieved by comparing backfilling options depending on the formation of rock natural self-supporting arch. The study is based on the provisions of structural mechanics and continuum mechanics using the phenomenon of performance of residual rock strength due to rock jamming. The backfilling concept has been formulated. Information on geological structure of the studied rocky ore deposit of complicated tectonic structure and the roles of tectonic framework in the behavior of the ore-hosting rock mass in the course of opening by mine workings are presented. The findings of the study of the rock mass condition with determination of characteristic geotechnical domains are presented. Variants of the ore-hosting rock mass behavior are considered depending on natural jamming of elementary structural rock blocks within the arch. The possibility of combining sealing and setting-mix backfilling methods has been clarified. The area of the research findings application in mineral underground mining is recommended. The determination of dangerous displacement area boundaries in rock mass using the mechanism of discrete rock jamming allows achieving higher mining effectiveness while ensuring mining safety. The study results can be used in underground mining of minerals.

Based on the recent information about oil and gas production potential in Azerbaijan, a geological and geophysical assessment of deep formations has been made. Scientific criteria have been prepared in order to use them as a basis for new researches. It has been highlighted that the main oil and gas fields are associated with the South Caspian and Kura basins, which were subjected to intense sinking during the Mesozoic Era. The high production potential of the central part and deep formations has not been sufficiently shown in terms of quality and quantity. It is known that the exploration, production and assessment of oil and gas field potential strongly depend on the information collected about petrophysical parameters of the formation. Researches shall be conducted concerning the oil and gas regions in the Absheron and Baku archipelagos, where Mesozoic and Cenozoic sediments are widely spread. Various geological, geophysical and physical aspects that had been influencing the reservoir potential of oil, gas, and gas condensate fields in that region have been studied. The conducted researches demonstrate that there is a thin layer of Pliocene anthropogenic deposits of 100 to 200 m in the paleoprofiles formed along the Kurdakhan – Shah Deniz offshore field in the northwest. The thickness increases towards Kum Adasi up to 3600 m and reaches 6000 m in Shah Deniz. Along the edges of the synclinal folds, the thickness of the abovementioned deposits reaches 3000 m in the northwest and about 10,000 m in Shah Deniz. Therefore, without sufficient knowledge about reservoir properties of the layer, it is impossible to assess the hydrocarbon accumulations and production volumes and change the exploration direction. In addition to geological and geophysical researches conducted in the area, lithologic, petrographic and reservoir properties have been studied in order to identify changes in the correspondence of carbon content, porosity, permeability, density, grain size distribution and sound wave velocity along the area to the properties of the abovementioned layer. For this reason, a table with the field reservoir properties has been prepared. It contains upper, intermediate and lower boundaries of physical characteristics, analyses the reservoir property interdependences and determines the formation depth and other physical aspects. The researches show that physical characteristics of coeval and homonymous rock change due to geological and physical processes and lead to different results. The reservoir characteristics of productive strata have been studied. A table has been prepared to show physical parameters of the area depending on time and place and to display different types and frequency of geological characteristics pertaining to the reservoir rock.

The research relevance is backed by the need to expand the resource potential of the western flank of the South Caspian basin and increase production in some oilfields of the Baku Archipelago. The aim of the research is to determine structural evolution features, paleogeographic, pressure and temperature environment and the deposition rate in order to assess oil and gas opportunities of the area under investigation. Methods. Paleotectonic and paleogeographic reconstruction of the area under investigation were conducted using computer software and a tectonic model of the deposition zone was constructed based on paleogeographic data. Results. The authors have constructed the schematic map, paleogeographic histogram, deposition rate diagrams for individual structures, paleotectonic profiles, a chart of the fold amplitude variation as a function of time and analyzed using computer technologies. The studies allow making the following conclusions: study of the history of geologic evolution of the local structures Aran-deniz-Dashli and Sabail showed that their development is syndepositional by nature; study of paleogeographic environments and deposition rates of individual stratigraphic units identified the presence of favorable paleogeographic conditions for accumulation of organic matter in source rocks of the section above the Clarke number; complication of local structures by mud volcanoes as well as analysis of geothermal data throughout the section allow making the conclusion on existence of quite favorable pressure and temperature environment for oil and gas generation in potential source rocks.

The article is devoted to the development of a new rapid method for determining the strength properties of rocks. A new express research method is required to meet industrial safety requirements in the operation of coal mines. The article describes the procedure for conducting research in accordance with the developed express method. The paper describes the form of the indenter used in research. The publication discusses the mechanical properties of rocks most frequently used to solve mining and technological problems in Russia. The article resolved made the choice of indicators of mechanical properties of rocks with which the establishment of a correlation dependence is required. The publication describes the used laboratory equipment. It includes a special device «PSSh 1» and a laboratory stand for determining the energy intensity of rock destruction. The «PSSh 1» makes it possible to determine the strength of rocks in wells.

The study features the image of the revolution in the novel by V. Maksimov "The Nomadism to Death". The research employed the cultural-historical and mythopoetic methods, as well as the method of motivational analysis. Since the novel has a complex multistage structure, the image of the revolution is considered according to the levels of the text: 1. The real layer of time, featuring the generation of fathers, who participated in the revolution and civil war. For them, revolution is significant: this is what they lived, killed and died for. The image of revolution evokes respect and worship, as well as regret about its incomplete. On this level, the revolution is closely connected with the time of the Civil War, which became its continuation. 2. The metatext level (the level of the explicit author-narrator Mikhail Barmin) unites the metatextual construction of the novel (which includes the present, Barmin’s past and "a novel inside the novel" about the time of the revolution and the civil war) and fits into the artistic conception of the writer's time: Maksimov depicts the time as a deadly chaotic circle, guiding the destinies of his characters and the land that repeats its history again and again, and in the whole of humanity as a whole. 3. Author's point of view (implicit author) – the revolution appears in the form of chthonic creatures, monsters devouring their children, demanding blood sacrifices and human lives.

In market economy, quality indicators of the extracted minerals are of particular importance. Decreasing ore losses and dilution can be achieved by controlling stress and strain using the residual bearing capacity of the broken rocks with the priority condition of preserving the earth's surface from collapse. The study aim is to substantiate rational parameters of mining methods based on the criterion of geodynamic safety. The aim is achieved by solving a set of mining tasks that ensures correctness of the obtained results, from assessing geotechnical condition to developing measures to prevent environmental impact of mining operations. The research methods include systematization and review of theory and practice, results of experimental studies and scientific forecasting. Importance of the mining system optimality criterion reflecting preserving the earth's surface from collapse to prevent contacting mining zone with habitat of beings (flora, fauna, and humans) has been substantiated. The mechanism of structural blocks interaction in discrete gravitational-tectonic-structural field has been detailed. The mechanism of broken rock blocks residual bearing capacity manifestation was clarified. The ways to increase the residual bearing capacity are: limiting the span size, optimizing strength of backfilling mixtures and pillar size to create geotechnically stable areas with minimizing the cost of managing the earth’s surface condition. Typification of methods for calculating spans of flat roof is proposed. Classification of rock mass management methods is given, the feature of which is assessing the worked out space condition as of pillar extraction completion, but not at the time of stoping. An example of the earth's surface preservation during mining of flat-dipping deposit with preservation of the earth's surface without backfilling the voids is given. Managing the condition of rock masses and the earth's surface above them allows monitoring of mining at all LoM stages. The use of geotechnical factors in organizing mineral extraction is a tool for implementing resource-saving and environmental-friendly trends in mining and a way to improve quality of ore mined while ensuring the enterprise competitiveness.

The paper presents the findings of studying deformational changes in rocks connected with development of oil and gas fields and operation of underground gas storages (UGS) through the example of Garadag field/UGS in the South Caspian Basin (SCB). On the basis of repeated well-logging measurements, it was found that over relatively short monitoring period (from 8 months to 2.5 years), development of VII level of the productive stratum (Lower Pliocene) of Garadag gas condensate field in the South Caspian Basin led to decreasing permeability of rocks in the range from 1.2 to 4.9 mD, with pressure drop from 2.4 to 11.7 MPa. The relative decrease in permeability ranges from 41 to 56%, while the higher values are typical for highly porous rocks. It is shown that multiple cycles of changing loads on the stratum in the process of the field/UGS development also contribute to the development of deformational changes in the rock, which lead to disruption of the rock matrix. This conclusion is supported by precipitation of about 25 - 30 tons of sand in the separator and liquid tank at the Garadag UGS facility in the end of each season. The sand is a product of rupturing rocks of the underground reservoir. This leads to irreversible changes in permeability and porosity of the reservoir rocks, which are sharper reflected in the change in the rock permeability. Deformational changes in the stratum caused by exploitation of the field and UGS lead to decreasing well productivity and injectivity.

In connection with changes in the stress-strain state of the Earth's crust, various physical and mechanical processes, including destruction, take place in the rocks and are accompanied by tectonic earthquakes. Different models have been proposed to describe earthquake preparation and occurrence, depending on the mechanisms and the rates of geodynamic processes. One of the models considers crustal stretching that is characteristic of formation of rift structures. The model uses the data on rock samples that are stretched until destruction in a special laboratory installation. Based on the laboratory modeling, it is established that the samples are destroyed in stages that are interpreted as stages of preparation and occurrence of an earthquake source. The preparation stage of underground tremors is generally manifested by a variety of temporal (long-, medium- and short-term) precursors. The main shortcoming of micro-modeling is that, considering small sizes of the investigated samples, it is impossible to reveal a link between the plastic extension of rocks (taking place in the earthquake hypocenter) and the rock rupture. Plasticity is the ability of certain rocks to change shape and size irreversibly, while the rock continuity is maintained, in response to applied external forces. In order to take into account the effect of plastic deformation of rocks on earthquake preparation and occurrence, we propose not to refer to the diagrams showing stretching of the rock samples, but use a typical diagram of metal stretching, which can be obtained when testing a metal rod for breakage (Fig. 1). The diagram of metal stretching as a function of the relative elongation (to some degree of approximation and taking into account the coefficient of plasticity) can be considered as a model of preparation and occurrence of an earthquake source in case of rifting. The energy released in the period immediately preceding the earthquake contributes to the emergence of its precursors. This article discusses various earthquake precursors with reference to the energy model of tectonic earthquake preparation and occurrence in conditions of crustal stretching.

Data on the diamond synthesis in experiments with carbon-saturated metal melts at moderate pressures and temperatures are presented. Features of the resulting diamond phase, the types and nature of inclusions are discussed and compared with those for natural microdiamonds found at the volcanic rocks of Kamchatka.

Relevance of work is caused by need of a solution of the problem of increase of efficiency of drilling of deep wells for solid anisotropic rocks. Work purpose: Research and development of new model of a diamond drill bit for drilling of solid anisotropic rocks. Research methods: Analytical researches and experimental works new diamond crown at the boring stand. Results: The model of the new diamond crown allowing to realize drilling of anisotropic rocks is developed. Data of the analytical analysis and technique of experimental works at the boring stand are submitted. Skilled drilling is carried out by a new crown which showed features of mechanics of work of a skilled crown that allows to carry out improvement of a design of the boring tool. Are determined consistent patterns of influence of parameters of the mode of drilling on character and intensity of wear of a crown, mechanical speed of drilling, power consumption of process of drilling. Conclusions. The skilled crown developed for conditions of drilling of wells in solid anisotropic rocks in the conditions of experimental drilling showed the high performance. The received results of experimental works confirmed the analysis and allowed to specify the mechanism of work of a skilled crown at various parameters of the mode of drilling with application as the clearing agent as waters, and emulsions. New data on the mechanism of work of a crown will be used for a crown prototype design creation of the perfect that will allow to receive more perfect boring instrument for drilling of solid anisotropic rocks.

Relevance of work is caused by the need to solve the problem of controlling well direction when drilling. The main aim of the study is to obtain the analytical dependences for calculation of an overturning moment arising at rock destruction by anisotropic mountain. The moment destabilizes the work of a roller cone bits; and to determine the analytical relation of bit design features with the size of this power factor. The methods used in the study: the analysis of results of experimental works on mechanics of anisotropic rocks destruction by boring bits and indentors of various forms, analytical researches of rock destruction, comparison and analysis of convergence of the obtained data and formulas. The results. It was ascertained that one of the major power factors causing a curvature of wells at destruction of anisotropic rocks is the occurrence of the overturning moment caused by an inequality of elastic and strength properties of rocks. The size of the moment is determined by the size of axial effort, the size and the form of rock cutting elements, as well as by the parameters of anisotropy of physic-mechanical properties of rock and by the boring tool and rock layers angle of incidence. The avlue of the overturning moment at anisotropic rock destruction by a roller cone bit changes for one turn of a chisel rotation on a face. The number of the maximum and minimum values as well as their fluctuation amplitude depends on a number of roller cone bits and a tilt angle of cone roller rotation axes in relation to a well face. The mentioned feature of the overturning moment size fluctuation can be used when designing configurations of a boring column to minimize the influence of the overturning moment on a curvature of wells, drilling in anisotropic rocks. Well curving in anisotropic breeds drilled with roller cone bits, is defined by the mechanism of rock destruction and its features. The dual nature of rock cutting action - rock crush by axial force and rock crushing by slanting by a blow at an angle to a face is included into the process and also some design features of arms of bits. A form and sizes of rock cutting inserts, an angle of their sharpening as well as the scheme of rock cutting inserts installation in wreaths of roller cone bits can be referred to the features of arms of the roller cone bits influencing the destruction of anisotropic rock and occurrence of the overturning moment.

About 25% of world oil and gas wells have fluid cross-flows between layers of different strength. Occurrence of cross-flows during performance of oil and gas wells significantly decreases efficiency of development of an entire reservoir. Usually cross-flows occur over the bond between cement and rock that in most cases caused by lack of adhesion between them due to clay cake on the well bore surface. Clay cake is characterized by fragile loose mineral structure that affects cement properties as well. It is impossible to fully remove clay cake from well bore surface by existing means such as scrapers, abrasive spacers, flow turbulization and flow change. That makes a challenge to increase cement quality by chemical influence on clay cake relevant. Proposed idea to increase well cement quality is to develop polymer spacer based on high-molecular polymers able to harden clay cake. Results of laboratory study of influence of temperature and thickness of clay cake on the quality of bond between cement and rock are presented. Results of study of polymer spacer influence on adhesion between cement and rock are shown. There was an effort made to reveal mechanism of spacer effect on clay cake. It is shown that injection of agents that harden clay cake and make system “cement–clay cake–rock” increase efficiency of layer isolation in the casing annular.

The article is devoted to the most narrative side of modern petrography – the definition, classification and nomenclature of petrographic structures. We suggest a mathematical formalism using the theory of quadratic forms (with a promising extension to algebraic forms of the third and fourth orders) and statistics of binary (ternary and quaternary, respectively) intergranular contacts in a polymineralic rock. It allows constructing a complete classification of petrographic structures with boundaries corresponding to Hardy – Weinberg equilibria. The algebraic expression of the petrographic structure is the canonical diagonal form of the symmetric probability matrix of binary intergranular contacts in the rock. Each petrographic structure is uniquely associated with a structural indicatrix – the central quadratic surface in n-dimensional space, where n is the number of minerals composing the rock. Structural indicatrix is an analogue of the conoscopic figure used for optical recognition of minerals. We show that the continuity of changes in the organization of rocks (i.e., the probabilities of various intergranular contacts) does not contradict a dramatic change in the structure of the rocks, neighboring within the classification. This solved the problem, which seemed insoluble to A.Harker and E.S.Fedorov. The technique was used to describe the granite structures of the Salminsky pluton (Karelia) and the Akzhailau massif (Kazakhstan) and is potentially applicable for the monotonous strata differentiation, section correlation, or wherever an unambiguous, reproducible determination of petrographic structures is needed. An important promising task of the method is to extract rocks' genetic information from the obtained data.

The offer of Polish radio stations is relatively extensive. Polish radio market offers many radio stations with diversified music profiles. This collection also includes rock radio stations. In this paper, the main aim was to prove that rock radio stations in Poland have a special tastemaking and educational function, both by presenting varied subgenres of rock music and by demonstrating history and curosities of rock genre. In addition, they inform users about the most important, current music events. Their news shows are full of miscellaneous informations. Morning shows in those radio stations have an ‘easy-going’ form and contain many humorous elements aimed at making the audience laugh and feel better. The article is also dedicated to the history of rock music the etymology of word rock and the problems associated with defining this genre. Moreover, there were demonstrated selected, historically important rock radio stations and the current structure of rock radio stations in Poland. What is more, this paper contains part about most popular rock radio stations – Antyradio and Eska Rock, which were analyzed in terms of music, programmes and other broadcasts aired on these stations.

The relevance of the work is caused by the need to combine the principles of economic efficiency of array state control while filling the cavities formed when mining and safety of the environment in the area of mineral resource extraction with the increase in volumes of extraction of mineral raw materials for the needs of the growing population. The aim of the research is to develop the parameters of ore extraction technique without filling the cavities with the material. These materials would preserve the earth surface from destruction in the case of rock caving zone yield to the level of pumps for indefinitely long period of time after filling the workings. Research methods: critical analysis of the experience in development of deposits similar in ore localization conditions, physical and mathematical modelling of the production technologies and forecasting the ways of development of technology, experimental determination of the value of a span limited in stability condition. Results. It is shown that the earth surface stability over the filled deposit area after its performance is provided with preventing the possibility of deformation phenomena occurrence. It is proved that the field with the void volume of 2 million m3 can be repaid without filling voids with backfill material. The authors have substantiated the necessity of a more complete accounting of geomechanical factors in assessment of environmental and economic efficiency of extraction of mineral raw materials. The paper introduces the model of estimation of underground mining efficiency depending on the use of properties of ore-bearing massifs. Conclusions. Purposeful use of the properties of ore-bearing massifs largely determines the performance indicators of underground mining. One of the main operational issues is the choice of development options to ensure the safety of the earth surface.

Bearing strength calculation of end-bearing piles under recognition of cohesive friction on the pile surface Vladimir S. Utkin Vologda State University (VSU), 15 Lenin st., Vologda, 160000, Russian Federation ABSTRACT Introduction. It is a drawback of the existing end-bearing pile design method for soil base bearing capacity that the latter is not taken into account in the assessment of the foundation soil action above the rock or a low-compression soil layer in all cases in accordance with the Building Code 24.13330.2011. However, taking into account the bearing capacity of this layer of the soil base in the load accommodation by the end-bearing pile (under recognition of the pile weight) could increase its calculated bearing capacity by the respective value of the soil base bearing capacity in combination with the soil support action under the pile’s lower end. The objective of the research is improving the trustworthiness of the calculation result of the bearing strength of end-bearing piles in the soil base, identifying the pile’s bearing strength reserve by taking in account the additional soil base bearing capacity due to the cohesive friction on the side surface of the pile. Materials and methods. The object of the research are piles of any applicable materials. The methods of calculation of the end-bearing piles are based on on cohesive friction values and their distribution along the pile length in a limit state calculation model in terms of the soil base bearing capacity. Results. The paper presents the equation of the ultimate compression load of the end-bearing pile in terms of the foundation base soil bearing capacity and the formula for the base soil bearing capacity reserve factor of the pile. The calculation of the pile bearing strength in terms of the material strength is referenced in the bibliography. Conclusions. A calculation method of end-bearing piles bearing strength was developed based both on the bearing capacity of soil base under the pile lower end and the additional soil bearing capacity along the flanks of the pile. The method could be applied also for calculations of the bearing strength of deep slot-type foundations. A quantitative assessment of the end-bearing pile on the design stage of a building with a pile foundation is given, prerequisite is made for further studies of the action of end-bearing piles and development of design codes for various piles in terms of material, type of support action, methods of immersion in the soil, etc.

The article deals with the development and practical application of virtual laboratory works on the subject “Petrophysics”. The developed laboratory works determine the rock weight, rock gravity, calculate rock bulk density and fragmentation index, identify rock depositional gradient, detect tense and compression limits, using integral method and work out strength certificates

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The article describes the technology non-explosive rock failure. On the basis of theoretical studies found that the most advanced engineering solutions for the destruction of rocks is to create a non-explosive technology based on high-frequency oscillations. Established the main uses of technology non-explosive destruction of rocks on the basis of high-frequency oscillations. [ABSTRACT FROM AUTHOR]