The Republic of Azerbaijan has significant potential in the oil and gas industry, which is the basic for the country economy. Prospects for the development of oil and gas production technologies are largely determined by the effectiveness of geological and geophysical surveys and exploratory drilling. The features of the geology and oil and gas potential of the Azerbaijanian continental depression zones are considered for determining the targets for further exploration for hydrocarbons (HC). The analysis of such studies shows that the Srednekurinskaya depression (the Azerbaijani part) and the Guba-Divichinsky depression are superimposed with the corresponding features of the conditions for the formation and survival of hydrocarbon accumulations. Low oil and gas potential of the Miocene-anthropogenic strata of the discussed superimposed depressions is substantiated: this is due to low hydrocarbon potential of the rocks (especially the Lower Pliocene ones), as well as low temperatures insufficient for the conversion of organic matter to hydrocarbons. It is proposed to use poorly tectonized Jurassic and Cretaceous sediments, especially those overlaid by oil and gas generating Paleogene-Miocene strata (commercial accumulations of Muradkhanli type) as the HC exploration prospects.

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Gravity methods are widely used for processing of gold ores. But many aspects of these processing techniques require improvement. In the study, methods of fire assay, gravimetric, chemical, mineralogical analyses of gold ores were used. In terms of sulfide sulfur content and degree of sulfur oxidation, the gold ore is assigned to the low-sulfide type of ore in the primary zone. Mineralogical analysis showed the ore-bearing rock is represented by phyllite. Gold in the ore occurs mainly in the form of free large and fine particles. The fine gold is closely associated with pyrite. GRG test was carried out for assessing gravity dressability of the gold ore. The total gold recovery is more than 41 %. The highest gold recoveries were achieved at the first stage at 100 % of -1.6 mm ore grain size, and at the third stage at 80 % of -0.071 mm ore grain size. This indicates that both relatively large gold and fine free gold particles are present in the ore. This is also confirmed by mineralogical analysis. The GRG test results showed that the gold ore can be effectively concentrated using centrifugal concentrators. The level of gold recovery by gravity at the multi-stage ore grinding is quite high. When developing the ore concentration process flow sheet, gravity separation in centrifugal concentrators should be included.

One of the most problematic aspects in underground ore extraction in mining-disturbed rock masses is backfilling of man-made voids, which affect origination and redistribution of stress-strain state of the rock mass. Their existence in the earth's crust provokes subsidence/collapse of the day surface and also contributes to arising geomechanical and seismic phenomena. The purpose of the study is to substantiate environmental-friendly and resource-saving methods for backfilling of voids in underground ore mining based on revealing the features of rock integrity of the day surface and life-sustaining activity of the population living in the mining-affected area. The main negative consequences of the impact of mining on the environment and humans are high costs for conserving day surface and ensuring life-sustaining activity of the population living in the mining-affected area, as well as removing large areas of land from human activity, etc. Based on the study of a rock mass stress-strain state using geophysical and surveying methods, an environment-friendly method for backfilling of man-made voids in disturbed rock masses is proposed. It enables ensuring the integrity of the day surface and life-sustaining activity of the population living in the mining-affected area (in the vicinity of mines, dumps, sites of backfilling complexes, preconcentration and heap leaching of metals from substandard ores, tailings storage facilities, etc.). Combined geotechnologies are proposed for backfilling of voids during the development of ore deposits by underground block leaching, and scientific and methodological and technical support was provided for drilling and blasting preparation of hard ores and underground leaching of pilot blocks at the Michurinsky deposit of GP VostGOK, Ukraine. The research findings can be used in underground mining of ore deposits of complicated structure.

Globalization of the energy feedstock market has led to the fact that, in recent decades, parameters of the thermal coal market significantly changed. Depletion of “rich” deposits implies development of new deposits of more complicated structure and characteristics. The paper proposes a new approach to managing quality of marketable products in the course of development of a coal deposit of complicated structure, which has demonstrated its effectiveness in the conditions of the Beisky deposit. The approach to managing quality of the marketable products is based on the concept of the relevance of improving the quality of technological processes and their differentiation according to the criterion of the maximum ratio of value and cost of the products. Typical solutions are proposed, and the results of implementation of the developed methodological approach to managing quality of the marketable products as exemplified by the Vostochno-Beisky open-pit coal mine are presented. Methods of analysis of technological factors governing the selection of parameters of the process operations were used, and the substantiation of the processes for preparation of blocks, excavation, transportation, storage and processing of products in conditions of open pit mining of a coal deposit having complicated structure was performed. The implementation of the developed technological solutions in the conditions of the Vostochno-Beisky open-pit coal mine allowed to obtain positive results, expressed in the growth of quality indicators of the marketable products by 4-6 %.

The tasks of continuous optimizing production, looking for ways of increasing performance, cutting mining costs and expanding mineral resource base of a mining enterprise are becoming more relevant than ever in conditions of the current negative trends at the world market of uranium resources. Increasing enterprise competitiveness requires permanent improvement of approaches and methods for managing performance of production blocks of a mine and ensuring the necessary volumes of reserves prepared for production. In the study, a theoretical information analysis of the process flow sheet of commercial ISL uranium production was carried out. The regression relationships between the main indicators of the production process cycles were determined, and the task of controlling production blocks at the stages of acidification, active leaching, completing operation, and decommissioning was formalized. The statistical characteristics of a production block cells and the distribution of uranium reserves, obtained based on the data of ore body drilling-in, as well as the analysis of the dynamic pattern of uranium production and recovery by production block depending on time, the balance of production block productivity by pregnant and leaching solutions enabled calculating key geotechnological indicators that formed the basis for calculating regression relationships between the uranium recovery and the ratio of the leaching solution amount to the rock mass amount, as well as for estimating specific consumption of sulfuric acid and electricity depending on operation time. This approach allowed identifying the problem areas and promising ways for improving the control procedure and performance of ISL mine wellfield operation. The planned measures will allow re-estimating resource potential of a production block while simultaneously providing a reasonable forecast of the residual uranium reserves in the being exploited and drilled-in blocks, reducing costs at the main development stage, and, by providing timely decommissioning of the blocks, reducing power consumption, optimizing sulfuric acid consumption, and overall improving quality of projecting and planning the production indicators for achieving uranium production targets. The study results can be used for improving short- and medium-term planning of technical and economic indicators of main development and production based on the forecast of ore interval sizes in production blocks that contributes to strengthening resource base and increasing capitalization of a company.

The Earth remote sensing technologies (ERS) in exploration largely determine their effectiveness. Therefore, development of a new methodological support for the use of remote sensing data in predicting mining and geological conditions is a key priority area. The studies are based on the analysis of the assessment of information, social, and economic efficiency of remote sensing data application at mineral deposits. The role of application of new technologies (including remote ones) in the process of optimizing initial exploration stages is noted. The possibilities of using remote sensing data to assess general nature, direction, and extent of environmental changes due to mining activities are shown. A technique is proposed that can be used in the process of tracking changes in the topology of objects in the course of mining. The differences in the results obtained using the proposed technique for processing satellite images on rectangular and hexagonal grids (rasters) are considered. The advantages of using the hexagonal grid for tracking the boundaries of objects and formation of signs are shown. Practical examples - a number of open source satellite images processed using the proposed method - are presented. The study findings allow applying intelligent analysis of satellite imagery data with the subsequent identification of the earth's surface objects of interest. An example of using the obtained results together with specialized software tools (such as GIS INTEGRO geographic information system capable of solving geological problems, or the foreign ArcGIS system) for constructing contour maps of the territory and obtaining its description based on topological relations and metric information is shown.

Development of economic sectors related to mining and processing industries is largely determined by national approaches to subsoil use regulation. For the Republic of Kazakhstan, having enormous geological potential, it is relevant and significant to develop and use globally competitive approaches to public administration of subsoil. Achieving these goals allows building in foreseeable future the potential for consistent and secure participation of the national economy in market interaction with leading global partners on mutually beneficial terms. In the paper, emphasis is placed on the fact that, despite forecasted promising geological data, significant excess of the scope of mining work over that of exploration is observed in the Republic of Kazakhstan. This is accompanied by low investment potential of the exploration sector. To solve the accumulated problems in the field of subsoil use, an analysis of the current situation was carried out, the causes of the current circumstances were identified, and the suggestions were made for improving the system of and approaches to public administration of subsoil, with justification of their effectiveness. The analysis convincingly showed that the reforms carried out in the field of subsoil use in the Republic of Kazakhstan and the changing trends in the global economy strongly require revising the previously used approaches to public administration of subsoil for developing the most effective system of public administration of subsoil. The study examined the international experience of public administration of subsoil in the countries that have achieved the greatest progress in this field, identified the basic principles in building a system of public administration of subsoil use, conducted historical analysis to determine the effect of the methods and approaches selected by state for subsoil administration at different stages of economic development. Based on the study findings, the risk zones of inefficient public administration of subsoil were identified, and approaches to improving the system and methods of public administration of subsoil in the Republic of Kazakhstan were proposed.