The evolution of the oil and gas industry in Azerbaijan has been associated with the emergence of distinguished statesmen and outstanding professionals in the field of science and education. These specialists have made a substantial contribution to the technological development of Russia and the USSR, including its oil and gas sector. This article extends the report presented at a plenary section of the International Scientific Conference “Formation and development of the oil and gas industry — the contribution of Russian and Azerbaijani scientists and specialists.”

   Background. Development of an oil field at the third stage causes certain difficulties for a subsoil user associated with the falling oil production, which requires additional measures to replenish the resource base. In addition to clarification of the geological structure of the deposit under development, the search for new oil deposits contributes to increasing the available reserves thus reducing the rate of decline in production. The availability of geological models for promising objects, created based on modern approaches to processing and interpretation of 3D seismic data, increases the efficiency of geological exploration and reduces the production costs. In the Southern license area of the Priobskoye field, its Jurassic interval is considered to be a promising area for exploration, given that the confirmed productivity of the Tyumen Formation in a large number of fields in the Khanty-Mansi Autonomous Okrug–Yugra.

   Aim. To develop a conceptual geological model of the YuS2–3 formations, which is the most promising part of the Middle Jurassic strata in terms of oil potential, by re-processing and re-interpretation of seismic data for the entire license area performed in 2020. A detailed analysis of information on the lithological structure and oil potential of the studied area.

   Materials and methods. Mapping of potential hydrocarbon traps was performed taking the following factors into account: presence of oil mother strata, migration pathways, reservoir, cover and deposit integrity. Improving the reliability of these factors seems to be key to successful exploration. In our opinion, the assessment of two factors, i.e., migration pathways and reservoir presence, can be significantly improved with the help of paleogeographic interpretations based on chromatic processing of eXchroma^SG seismic.

   Results. The results of conceptual modeling were used in planning of exploration works. The results were validated during implementation of the exploration drilling program in 2021—2022. The drilling results confirmed the oil bearing capacity of the upper part of the Tyumen Formation.

   Conclusion. The application of the hydrocarbon prospecting methodology based on seismofacial analysis of Jurassic sediments confirmed the oil-bearing potential of the Southern license area of the Priobskoye field, thereby increasing the resource base by discovering new deposits.

   Background. The current state of exploration and development of oil and gas fields in the Caspian Sea is considered.

   Aim. Identification of new engineering and technological features of exploration and development of oil and gas fields in the Caspian Sea.

   Materials and methods. An analysis and typification of mining and geological conditions and parameters of oil and gas deposits, as well as traps and reservoirs, was carried out. The current state of oil and gas exploration and development in the Caspian Sea was assessed by statistical generalization and systematization of data and materials, partially borrowed from reference literature, stock sources, field data, and published works.

   Results. The conducted analysis revealed the main engineering and technological features of the current state of exploration and development of oil and gas fields in the Caspian Sea. These include the creation of special hydraulic structures and floating technical equipment, taking harsh marine hydrometeorological conditions for drilling prospecting, exploration and production wells into account; drilling directional clusters of wells from individual stationary platforms, pier platforms, artificially created islands, jack-up-type and semi-submersible floating installations and other structures both above and below water; selection of a rational design and number of stationary platforms, pier platforms, floating production decks, and other structures for placing the optimum number of wells; creation of special engineering means and technological processes, as well as floating installations that ensure the protection of the marine environment during drilling operations, borehole operation and repair. The need for platforms in the Caspian Sea as a whole in the period until 2025 is estimated at 71–87 units.

   Background. In this article, we investigate geological, geophysical, and physical aspects that affect the reservoir capacity of oil, gas, and gas condensate fields in the area of the Neft Daşları deposit.

   Aim. The aim was to study the lithologic and petrographic features of deep-seated strata, as well as their reservoir properties, and to reveal regularities of their change with depth.

   Methods and materials. To that end, the parameters of carbonation, porosity, permeability, density, granulometric composition, and longitudinal seismic wave propagation velocities were determined. Rock specimens of the Neft Daşları field were collected from exploration wells.

   Results. The minimum, average, and maximum limits of the physical properties of rocks were established. The dependence of reservoir properties and other physical factors on the depth of rock occurrence was considered. The results obtained allow us to assume the oil and gas bearing capacity of deep-seated strata along with those already under operation.

   Background. This work substantiates the dependence of the development modes of rift basins of the Late Phanerozoic of Afro-Arabia on the size and age of the Lower crust structures (granulite belts) in which they were laid. The author proposes a model to correlate the rifting process with the centers of evolution and regeneration of the African superplume and the spread of heated superdeep material from these centers through the channels of granulite belts.

   Aim. To clarify the signs and causes of the final differentiation of rift basins into the tectonic types of incomplete and completed development, as well as the tectonic prerequisites for the migration of rift formation from south to north and from west to east.

   Materials and methods. The study was based on a review of scientific publications, mainly by foreign authors, on the geology of rift basins and crustal complexes. A comparative analysis of geological and geophysical data related to rift basins of different tectonic types was conducted.

   Results. The following patterns of rift basin development were identified. (1) The final tectonic differentiation of basins and their sedimentation structures of the African granulite belts along which the basins were laid. (2) Rifting migrated from south to north and from west to east from younger granulite belts to older belts with a distance from the evolution centers of the African superplume. In this regime, the magmatic basins of completed development were replaced by amagmatic basins of both tectonic types. (3) The migration of rifting from the end of the Paleozoic in the south and the Triassic in the west to the Late Cenozoic between Africa and Arabia was accompanied by a reduction in time intervals and an increase in the rate of deflection of the basins created by this process.

   Conclusion. For the first time in Afro-Arabia, the spatial and temporal dependence of rifting on the size and age of the pan-African granulite belts, along which it occurred, and their location relative to the centers of the African superplume was substantiated.

   Background. Turquoise is known to occur in Northern Tajikistan, while variscite is found in Central Tajikistan. Turquoise mineralization is represented by Biryuzakan deposit and four occurrences: Biryuzasay, Shorbulak, Karamazar, Kyzyltash, which are located in the center of the largest mining district Karamazar, on the southern slope of the Qurama Mountains. The turquoise occurrences of Samarkandek and Isfara are situated in the northern branches of the Turkestan Range. Variscite mineralization is located in Central Tajikistan, on the northern slope of the Zarafshan Range, in the upper reaches of the Shing River, on its left side, in the area of a small gold-antimony deposit Chorraga and in the area of a large deposit of Jijikrut. Formation of turquoise and variscite has many common features, thereby allowing them to be considered together as hydrothermal-metasomatic minerals.

   Aim. To summarize geological materials, taking into account new data obtained regarding turquoise and variscite in the territory of the Republic of Tajikistan, and to analyze the processes of their formation.

   The study focuses on the Biryuzakan deposit and six occurrences of turquoise as well as two occurrences of variscite.

   Materials and methods. Rock samples were collected at the Biryuzakan and Chorraga deposits in 2022—2023. Photographic documentation of mine workings and a major regional fault — Biryuzovy Fault — was conducted. A tectonic map of turquoise and variscite occurrences was compiled using literature data. Cartographic, structural, and mineralogical methods were employed for this purpose.

   Results. For the first time, the study introduced a geological summary of all known deposits and occurrences of turquoise and variscite in the territory of the Republic of Tajikistan and a tectonic map of their location. A new, hydrothermal-metasomatic formation mechanism is proposed, wherein
the substances for turquoise and variscite (copper, aluminum, and phosphorus) were sourced from host volcanic and siliceous rocks through a lateral-secretion process.

   Conclusion. The proposed hypothesis regarding the formation of turquoise and variscite serves as an alternative to existing views shared by many prominent specialists in the field of gemstone geology.

   Background. The study examines the petrochemical characteristics of clayey deposits from the Dyakhtar Formation in the Nakyn Kimberlite Field, which contain material from redeposited weathering crusts of the Late Triassic to the Early Jurassic age. Currently, this Formation is considered the most promising for scandium mineralization compared to other areas in the Malo-Botuobinsky and Ygyattinsky diamond-bearing regions of Yakutia with the identified scandium concentrations.

   Aim. To establish the geochemical characteristics of scandium concentrations in the sediments of the Dyakhtar formation of the Nakyn kimberlite field.

   Materials and methods. Using petrochemical modules, 9022 X-ray fluorescence analyses of rocks of the Dyakhtar formation were analyzed, performed at the Vilyui Geological and Exploration Laboratory of ALROSA,

   Results. The recalculation of the petrochemical modules has revealed that the Dyakhtar Formation comprises the following components in different proportions: clayey rocks (42 %), clayey silicites (31 %), weak clayey silicites (15 %), hydrolyzate clayey rocks (9 %) with an admixture of silicites (4 %). The vast majority of samples with scandium concentrations exceeding 100 g/t were found in hydrolyzate clayey rocks (83 %), which contain products of mature weathering crusts. In addition, scandium-bearing rocks are characterized by formation under continental conditions, by normal
iron content and lack of translocation, as well as a weak alkaline environment.

   Conclusion. The observed systematic changes in the correlation coefficients Sc/V, Sc/Ti, Sc/K, and Sc/Rb with increasing scandium concentrations suggest probable forms of scandium occurrence in vanadium-bearing titanomagnetite and its sorption in montmorillonite.

   Background. New energy-saving technologies induce the implementation of alternative heat supply sources, including heat pump systems. One of their operational schemes utilizes low-grade heat from groundwater aquifers. The paper substantiates the selection of the most optimal operational scheme based on model calculations.

   Aim. To conduct model calculations aimed at computing the feasibility of using groundwater aquifers as a low-grade heat energy source.

   Materials and methods. The hydrodynamic processes and heat transfer within the aquifer were studied using the GERA/E1.0 computational code, designed for three-dimensional geofiltration and geomigration modeling.

   Results. Several numerical models are developed for various operational schemes of groundwater aquifers. The most promising operational scheme was selected based on the calculations.

   Conclusion. The feasibility of using groundwater aquifers as a low-grade heat energy source has been quantitatively assessed. The most optimal operational scheme has been selected.

   Background. The present study introduces the results of mathematical modeling for the scenario when a line of harmonically varying current at frequency f serves as a specified field source, positioned along a horizontal boundary of a conductive half-space. The computed parameters pertain
to the characteristics of the vertical component Hz of the alternating magnetic field in the air. The modeling is based on the solution of the corresponding direct problem in electrodynamics.

   Aim. To justify a potential methodology for measurements in electromagnetic survey utilizing unmanned aerial vehicles (UAVs).

   Materials and methods. The study involves mathematical modeling and analysis of the obtained results.

   Results. The calculation results were obtained for a model corresponding to the scenario when a grounded generator line AB carrying a harmonically varying current I is positioned along a horizontal boundary of a conductive half-space with specific electrical resistance ρ₂, and a magnetic induction sensor located in the air is moving at a considerable height h above this boundary.

   Conclusion. The results of the modeling indicate the most “sensitive” characteristics of the magnetic field to the values of ρ₂, namely, the active component of Hz, which differs in phase from the current I by ±π/2, and the initial phase of this component.

   Background. In addition to anthropogenic activities affecting the environment, geological hazards pose significant risks to the natural environment, as well as to human population, buildings, and infrastructure. In the Caspian region, geological hazards are primarily associated with geodynamic activity and dissipation of fluid-dynamic stress within the hydro- and lithodynamic flow systems in the subsurface, which manifests in the form of intense upward flows of mobile fluids that significantly impact the surrounding environment.

   Aim. To investigate and assess the current geological processes affecting the environment of the Caspian region.

   Materials and methods. The computer processing and visual interpretation of radar information, as well as the data of marine geological-geophysical and seismic studies, revealed correlation of oil slicks and gas emissions with the sources of fluid generation and discharge within the sedimentary cover of the Caspian region. The correlation between the occurrence of oil slicks and regional seismic activity was evaluated using data from the USGS National Earthquake Information Center concerning earthquakes in the Southern Caspian region.

   Results. The conducted studies evaluated the scale of current geological processes that affect the environment of the Caspian region. In addition to anthropogenic degassing, the role of deep and crustal degassing of the Earth has been found significant in this region. Natural oil and gas showings are spatially and genetically linked primarily with geological processes—vertical and horizontal movements, seismicity, including sedimentary—small-focus seismicity, mud volcanism, the migration and emigration of hydrocarbons, as well as the accumulation of free gas in the upper part of the sedimentary sequence.

   Conclusion. Crustal degassing is associated with the state and functioning of geofluid-dynamic systems, evolving and developing under the influence of geodynamic processes throughout the sedimentary filling at all stages of the basin’s evolution, with the active contributions of the generation and migration of methane, hydrogen, and other gases. Discharges of oil and gas in water exhibit significant variability, including local (concentrated) discharges (such as mud volcanoes, gas seeps, salt springs, slicks, and others), widespread hydrocarbon influx and its fractions from petroleum and gas-bearing structures via faults. Oil pollution in Baku Bay appears to be a consequence of natural fluid dynamic processes occurring in its subsurface. The sources of oil slicks refer to the areas where formation fluids are discharged in the sedimentary cover structures. The discharge is influenced by the seismicity of the Earth’s crust in the South Caspian tectonic basin.

   Background. The current geopolitical and economic situation makes the task of attaining the technological sovereignty of Russia particularly relevant. This also concerns the need to improve the current investment legislation in the country, including in the field of special investment contracts (SPIC). The SPIC is a form of public–private partnership, which should be primarily aimed at overcoming the technological gap and import dependence through the implementation of a phased import substitution and innovative development of the Russian coal industry and domestic mining machine building.

   Aim. To estimate the possibilities of using SPIC as a mechanism to stimulate investment and technological innovation in the process of import substitution of foreign mining equipment in the context of anti-Russian sanctions.

   Materials and methods. The research was based on the methods of system analysis, expert evaluation, technological foresight, logical and comparative analysis, economic and statistical processing of information, including its tabular interpretation. The data of coal companies and Rosinformmugol JSC, as well as those retrieved from Internet sources and open-access publications, were used.

   Results. The level of import dependence of the Russian coal industry on foreign mining equipment was evaluated. The possibility of using SPIC to stimulate investment and technological innovation in the process of import substitution of foreign mining equipment in the context of anti-Russian sanctions was estimated. The most critical positions in terms of dependence on imported mining equipment supplies were identified; proposals were made for possible sites to attract investors through the SPIC mechanism for localization of key technological mining equipment and components.

   Conclusion. The conducted estimation of the possibility of using incentive mechanisms showed SPIC to be an effective mechanism to stimulate the process of import substitution of mining equipment. It should be noted that the current geopolitical and economic situation makes the task of improving investment legislation, which also covers SPIC regulation, particularly important.

   Background. Scientific and technological progress, along with the development of high technologies, leads to a rapid increase in the variety of mineral resources used in strategically important sectors of the national economy. The growing significance of certain minerals for national security and the monopolization of the high-tech raw materials market encourage governments and the scientific community to develop concepts for ensuring national economies with critical mineral resources.

   Aim. To clarify the terminology related to strategic, scarce, and critical mineral resources, to establish criteria for classifying various types of mineral resources as critical, and to create an original list of critical mineral resources.

   Methods and materials. In order to achieve this aim, a comprehensive set of general and specific research methods was employed, including comparative analysis and synthesis, systematization and generalization, grouping, induction, and deduction.

   Results. The study involved analyzing definitions of strategic, scarce, and critical mineral resources used in both Russian and international practices. The need for introducing the category of critical mineral resources was substantiated to establish priorities in the strategic planning of the development of the country’s mineral resource base. Criteria for classifying certain types of mineral raw materials as critical have been developed and an original list of critical mineral resources has been compiled.

   Conclusion. The analysis of critical mineral resources listed by the author revealed that Russia possesses significant reserves and resources of most of these resources, and in some cases holds leading positions. A prerequisite for ensuring national economic security comprises the accelerated development of its own mineral resource base of critical mineral resources and the elaboration of innovative technologies for processing mineral raw materials. Anti-crisis state management can provide the necessary impetus in the given direction by mobilizing production, financial, human, scientific, and entrepreneurial resources.

   The textbook² under review examines relationships between the lithological features of sand-siltstone and carbonate reservoir rocks and their petrophysical properties. The reservoir properties of rocks depend on their lithological characteristics, being their function. As part of petrophysical
research works, specific features in the lithological study of reservoir rocks are determined, their main lithological and petrophysical properties are characterized, and the sequence of their study is considered. The textbook provides numerous examples confirming the unambiguity or ambiguity
of lithological and petrographic relationships identified by other researchers in the study of reservoirs of different ages. The textbook is based on the original material obtained by the authors when studying the oil and gas provinces of the Russian Federation.