Background and aim. Scattered waves are used to create diffraction seismic images. Within this work, two different seismic data processing scenarios were studied in order to determine their impact on diffraction images obtained using migration transformations.

Materials and methods. The real data went through a standard processing graph oriented on refl ected waves, and they were also processed within another processing graph with maximum preservation of the scattered component. In the work on that specific example we evaluate the possibility of using various processing scenarios to construct reliable diff raction images got by target-oriented asymmetric migration operator.

Results and conclusions. As a result, diffraction images of the target area are constructed from these data sets. From a comparative analysis of the constructed diffraction images we conclude that from data processed with a focus on reflected waves it is difficult, and in some places impossible, to construct reliable diffraction images, therefore it is necessary to carry out processing focused on scattered waves. Also, we conclude from that analysis that diffraction images obtained from data with the preservation of the scattered component are more reliable compared to the results for data a` er a standard processing graph, and they can be used for interpretation.

Introduction. One of the key problems in the search and exploration of oil and gas fields of the Siberian platform is a lack of substantiated fault maps that clarify the models of the geological structure of objects. Important factors are the geodynamic conditions of the formation of tectonic faults that affect the hydrocarbon accumulation.

Aim of this work was to map the fault-block structure of a local area of the Southern Siberian platform and reconstruct stages of its formation to identify discontinuities favorable for localization of oil and gas along them. The area is located 50 km southwest of the city of Ust-Kut.

Materials and methods. Tectonophysical analysis of data on faults and fracturing, river and relief lineaments derived from interpretation of topographic maps, satellite images and digital elevation models (from https:// search.earthdata.nasa.gov/search?q=SRTM); work materials of 2D seismic exploration, electrical exploration (ZSB method, volume — 1038 points), magnetic exploration (measurement step 250 m) and gravity exploration (measurement step 500 m).

Results. As a result of the research, we identifi ed six main stages of tectogenesis, which are associated with tectonic events in the Sayan-Baikal and Baikal-Patom folded regions of the Central Asian mobile belt. For each main stage, faults that could have formed or become active in a certain geodynamic setting were identified, and the slip type along them was reconstructed. According to the obtained tectonophysical model, the steeply dipping and inclined fault zones trending north-west, north-north-west, submeridional, north-north-east and north-east were favorable for saturation with hydrocarbons in the studied area at different times. The north-easttrending faults were synsedimentary and, at the stage of formation of hydrocarbon deposits, could increase the permeability of the strata. Migration of fl uids with their possible accumulation along the NW faults could have occurred in the fourth stage of shear deformation with the north-west compression axis and the north-east extension axis.

Conclusions. The studies carried out to map faults and study the stressed state of the earth’s crust for different time stages of the development of territories make it possible to more effectively search for oil and gas deposits, and the results may be useful for other adjacent territories that are promising for hydrocarbon exploration. 

Introduction. Reducing the cost of oil production is particularly acute in the context of the use of expensive methods to enhance oil recovery. The determination of optimal downhole equipment for gas injection wells can signifi cantly reduce operating costs and technological risks for gas injection.

Aim. Determination of optimal technological parameters of downhole equipment when designing the development of an oil and gas condensate field with associated petroleum gas injection.

Materials and methods. Analysis of geological and geophysical information on the field and application of existing international experience and techniques for determining the technological parameters of gas injection into reservoirs.

Results. Using the example of designing the gas and oil fild development, the approach and algorithms for determining the technological parameters of gas injection into the reservoir are described. The influence of reservoir characteristics on the final result is shown.

Conclusion. The technological parameters of gas injection into the reservoir have been determined.

Introduction. Today, high-viscosity oils present a significant fraction of hydrocarbon reserves. The production of such resources is possible by application of the steam-assisted gravity drainage technology. This process is technically complex and expensive procedure. One of the tools of the process forecast is the selection of the most signifi cant characteristics and assessment of their quantitative values of candidate fields for successful application of steam-assisted gravity drainage.

The aim of the article is comparative analysis of the results of experimental study of the steam-assisted gravity drainage process with the field experience of implementing this technology abroad and by Tatneft .

Materials and methods. The analysis of the main experimental and mathematical models of process is carried out, the advantages and disadvantages of the approaches are highlighted. A representative sample of projects has been obtained. Based on the analysis procedure, the key parameters determining process effectiveness under consideration are highlighted. The comparison of average values of the parameters for a group of Russian and foreign fields is carried out.

Results. A comparative analysis of field data made it possible to establish ranges of values of key parameters for the implementation of steam-assisted gravity drainage. The foreign experience of using the technology is compared with the pilot projects of Tatneft .

Conclusion. It is shown that the thermal problem prevails over gravitational segregation processes. In general, the main steps and features of the process established in experimental and theoretical investigations are presented in the fi eld pilots monitoring.

Introduction. The development of tight reservoirs is a technological challenge that needs synergetic work. This paper allows the results of the study of anisotropic elastic properties and stress state condition of the Achimov formation (AchS10, AchS12) related to the Harvutinskaya oil field.

Aim. The main goal of this research work was to choose the hydraulic fracture technology based on geomechanical modeling. That takes into account anisotropic elastic properties and stress state to determine the fracture height.

Materials and methods. A complex study program in the well was realized that includes sonic logging data in open hole and a` er hydraulic stimulation, thermometry after mini-hydraulic fracturing and after the main stage of hydraulic fracturing, pulsed neutron gamma ray imaging (NRT—non-radioactive propant), a study of VTI anisotropy, and the last one was a strength profile.

Results. A geomechanical model with anisotropic elastic properties and stresses was introduced. In the result, hydraulic fracture design was performed and validated on real study data from fracture high analysis.

Conclusion. A complex study allowed us to receive a full understanding of the Achimov formation stress state in the Xarvutinskaya area and choose eff ective stimulation technology based on isotropic and anisotropic geomechanical models.

Introduction. Due to technological and geological factors, there is a high rate of decrease in well productivity at the Achimov tight-oil reserves. The development at a large gas-condensate field with these reserves was often accompanied by hydrate formation, a stop of blowing and a drop in productivity with an intensive decrease in bottom-hole pressure.

Aim. To develop a methodology for selecting the optimal stabilization program for the project well, taking into account the experience of existing wells.

Materials and methods. The methodology includes assessment of hydrate formation conditions, evaluation of the possibility of blowing, and determination of allowable drawdown pressures. Hydrate formation conditions are assessed using a hydrate curve. Blowing conditions are evaluated using vertical lift performance (VLP) curves, where zones of stable blow, unstable blow, and a zone where liquid begins to accumulate at the bottom-hole, leading to blow cessation, are identified based on the slope angle. The minimum allowable bottom-hole pressure is determined based on the operating experience of existing wells, which shows that further bottom-hole pressure reduction leads to decreased productivity due to rock matrix compressibility and impaired proppant properties.

Results. The low productivity of the project well leads to the need to inject high-concentration methanol due to hydrate formation, as well as to short-term blowing. At the same time, lowering the downhole pressure below the threshold value of 300 bar is not recommended, as this will lead to an intense drop in well productivity.

Conclusion. The development of a methodology for determining stabilization program for wells allows you to maximize production and maintain well productivity for further work and research. The methodology tested in the above work is particularly relevant for vertical wells in low-permeability reservoirs, which, due to geological and technological factors, have low flow rates, which leads to their unstable recovering

Objective. Evaluation of the possibility of using foam checkers based on surfactants (SAS) for the purpose of removing water from the well bottom and intensifying the inflow by reducing the bottomhole pressure.

Materials and methods. Laboratory studies of SAS on foaming on the formation fluid of a test well showed high efficiency. The search for candidate wells was based on the analysis of pressure and density distribution curves along the wellbore, analysis of previously performed activities and geological and engineering operations  (GEO), as well as on the analysis of the results of modeling multi-variant solutions of nodal analysis.

Results. The test results showed high efficiency of using foam checkers based on SAS in wells after highvolume killing of gas-lift  wells, while the time of bringing to the mode is reduced by an average of 2 times. In the fund operating in the mode with water inflow from the formation and with a confi rmed column of water at the bottomhole, a short-term eff ect of 5 to 10 days was observed. Further, repeated treatment of wells with checkers was required.

Conclusion. Current characteristics of foam checkers based on surfactants allow their use to accelerate the well recovery after technological treatments. In a fund operating in a steady state, the use of foam checkers is possible provided that it is economically feasible. Also, one of the possible improvements may be the use of foam checkers together with design changes to the gas lift with a shank. 

Introduction. The problem of ensuring environmental safety associated with the formation of drilling waste during field development is relevant all over the world. The accumulation of large volumes of drilling waste leads to the need to find alternative ways to dispose of this type of waste. The accumulation of high drilling waste volumes leads to the necessity of searching for alternative waste disposal methods used in practice. Its transformation into a secondary raw material resource can be the one.

Aim. Improving the environmental situation, ensuring the environmental safety of the areas of development of offshore hydrocarbon deposits and the waters of ports through the processing of drilling sludge.

Materials and methods. The methodology of studying samples of drilling mud and soil mixtures for the study of chemical, toxicological and physico-mechanical properties included a complex of theoretical, experimental and bench studies, including: granulometry, petrography, electron microscopy, biotesting. Mathematical and statistical methods were used to process the research results.

Results. In this paper, a conceptual technological scheme for the preparation of solid drilling waste to be used as a basis for the production of building materials is proposed as an option. The main technological solutions for processing are focused on obtaining products using as building materials «in the field» — to strengthen the slopes inside oil field roads and cluster pads, in low-rise construction including enclosing structures, ancillary buildings, etc.

Conclusion. This research determined that during the preparation of cuttings for disposal, the volume of transportation of drilling waste is signifi cantly reduced leading to the possibility of its disposal both on the platform and on the coastal base as part of raw materials for the production of building materials.

Introduction. Results of five years pilot project of thermogel using for water coning and rapid watercut preventing treatments in Zapadno-Hosedauskoe field wells are presented. Zapadno-Hosedauskoe field is massive deposit of carbonate reservoir with high vertical permeability and underlying water.

Aim. The aim of investigation is summing up and efficiency estimation of water coning preventing treatment pilot implementations.

Methods. For coning evaluation Chan’s diagnostic plots and well flow profile were used. For additional oil production estimation base production trends were used.

Results. The pilot project has been realized at Zapadno-Hosedauskoe fi eld from 2019 to 2023. During this period, 34 treatments were executed, additional success criteria was determined, well candidates selection, treatment planning and effi  ciency estimation method was formulated, different compositions and various injection volumes were tested, different kinds of well intervention were applied, and also repeated and preventive (before putting of well on production) treatments were completed. Additional oil production due to pilot project realization is more than 270 000 tons.

Conclusions. Authors showed results of five years water coning prevention treatments pilot project, determined success well candidate criteria and estimated additional oil production. 

Introduction. The task of improving the efficiency of late-stage field development is an urgent challenge, requiring a balance between costs and current production levels. It is proposed to use a genetic optimization algorithm to identify wells whose shutdown will allow to obtain an increase in oil production and (or) reduce operating costs

Aim. Reducing optimization costs of oil fields through production reallocation decisions using optimization algorithms

Materials and methods. The approach of simplified modelling of the system ‘reservoir — well — gathering system’ with the use of an optimization algorithm, the target function of which is daily oil production was implemented. In this work, an algorithm for preprocessing and analyzing the input data was used, as well as the tornado algorithm for sensitivity analysis. The study, modelling and optimization were performed based on a proxy integrated asset model adapted to the actual data.

Results. The result of approbation of the approach is a program of measures for stopping and implementation of hydraulic fracturing at the producing stock, corresponding to the maximum value of the selected target function.

Conclusion. It was determined that the main difficulties in using the genetic algorithm for optimization are the high dimensionality of the problem and the topology of the acquisition network. To eliminate these difficulties, a well filter was created and a sector model of the collection network was used. As a result, the genetic algorithm switched off  the most watered wells of the fund as the best option, which is a criterion of the optimizer’s correctness.

Introduction. Effective managerial decision-making largely depends on having timely access to current information about asset status. Data on such business structures are typically fragmented and interdependent, necessitating a systematic approach to their consolidation and interpretation.

Aim. The article examines the experience of building a corporate data warehouse based on disparate data from operational source systems to enable comprehensive analysis of asset status.

Materials and methods. To achieve the goal, a list of key company performance indicators at diff erent management levels was determined, the advantages and disadvantages of the architectural approaches of William Inmon and Ralph Kimball to building a corporate data warehouse were analyzed, and the difficulties in eliminating inconsistencies in source system models and ensuring the required level of information security in architecture components were investigated..

Results. A real example of constructing a hybrid architecture for a corporate data warehouse based on the approaches of William Inmon and Ralph Kimball is provided. ETL processes for loading data into the warehouse and populating data marts have been configured. A module for loading data absent in the systems has been developed. Monitoring and risk analysis of the constructed architecture have been conducted.

Conclusion. Building a corporate data warehouse indeed presents numerous challenges in architecture development and ETL process confi guration. Real-world integration examples, including the one provided in this article, serve as valuable benchmarks for understanding implemented strategies. They demonstrate the practical application of integration frameworks, technologies, and methodologies, and offer insights into lessons learned and key factors that contributed to successful integration projects.

Introduction. In this article, the problem of the efficiency of oil pipeline leak detection systems is addressed. Internal methods based on the analysis of transported product parameters are limited by point sensor distribution and difficulties in non-stationary operating modes. External methods, such as distributed optical fiber sensors, offer more reliable and accurate leak detection. Field tests are necessary to confirm their effectiveness, as laboratory methods cannot reproduce real operational conditions.

Aim. The aim of the work is to develop and validate a methodology for field testing to assess the efficiency of distributed optical fiber leak detection systems (LDS). The study includes testing PLDS based on the distributed acoustic sensor “Dunai” (DAS “Dunay”).

Materials and methods. The field test methodology involves simulating leaks using non-destructive control points. Test spills create pressure waves that are registered by the optical fiber cable. The methodology also accounts for external noise factors, such as vehicle movement, heavy machinery excavation, and non-stationary pipeline flow regimes.

Results. Field tests conducted using the proposed methodology confi rmed the suitability of the method for validating the claimed characteristics of leak detection systems. The tests involved the Distributed Acoustic Sensor “Dunay” (DAS “Dunay”) and demonstrated its ability to accurately detect and localize leaks with high precision and reliability.

Conclusion. The developed methodology can be used for further testing and certification of similar systems under real-world operating conditions.

Introduction. In conditions of high corrosive aggressiveness of the produced products the actual task is to search for new solutions for protection of downhole equipment. This paper analyses existing solutions for corrosion control and proposes the use of an untypical corrosion protector to protect the wellhead tie-in from premature wear.

Aim. Development of a new technical solution to protect wellhead piping from corrosive wear and tear Materials and methods. Well performance data as well as data on geometric parameters of the corrosion protector were used as input data. The macro package in the VBA programming language was used to perform calculations.

Results. A new method of protection of wellhead piping from corrosion was proposed, a non-typical corrosion protector was developed, universal tool for selection of corrosion protector sizes was created, and the effectiveness of the proposed solution was proved by calculations

Conclusion. As a result of the analysis, calculations and pilot tests, it was determined that the corrosion protector is an effective method of corrosion control, as well as does not affect the mode of operation of the well. 

Introduction. This paper demonstrates the economic effect of implementing soft ware based on a digital twin that can forecast in real-time and provide recommendations for optimal operating modes of wells and processing facilities, relying on existing sensor data retrieved from the SCADA system and the target performance parameters of the extraction asset.

Aim. The aim of this work is to develop and implement a digital twin system for automated analysis and optimization of gas condensate asset operations, which will increase product output and reduce resource costs.

Materials and methods. The study utilized the so` ware “AEROSYM” and the module “Virtual process engineer” for real-time data integration and analysis. Modules were developed for calculating elements of the “reservoirwell-NGS-UKPG/UPN” system, hydraulic calculations of the gathering manifold, and automatic creation of calculation schemes. Modeling of the gas condensate studies during testing, trial, and development of wells was implemented, considering current measurements of volumetric flow rates.

Results. As a result of implementing the digital twin, resource savings were achieved: a reduction in methanol and electricity consumption by 2–5%. Additionally, through optimizing key parameters of the technological process, the output of marketable products from gas processing facility increased by 3% (LPG) and by 1% (stable condensate).

Conclusion. The implementation of a digital twin for monitoring and optimizing technical parameters of the gas extraction asset has demonstrated its economic efficiency. The system provides prompt calculations and decision-making support based on telemetry data, allowing for minimized costs and increased productivity. The main business effects include an increase in component extraction, enhanced gas production, and a reduced likelihood of technological complications.

Introduction. Surface wave analysis and inversion (SWI) is a valuable tool for constructing near-surface velocity models. It offers high noise immunity and does not require specialized acquisition systems. However, manual extraction of surface wave dispersion characteristics and the need for inverse operator fitting make SWI timeconsuming and impractical for large datasets.

Aim. This study aims to accelerate and automate near-surface velocity model construction using deep learning neural networks within the SWI framework.

Materials and methods. Deep machine learning methods, including a convolutional autoencoder model and a fully-connected neural network, were applied to achieve this goal. The developed algorithms were tested on synthetic seismic data generated using the matrix propagator method and validated using field data from ground seismic surveys.

Results. The proposed neural network architectures demonstrate high accuracy in automatically extracting and inverting surface wave dispersion curves. The mean absolute percentage error for extracted curves was 1 %, and 5 % for reconstructed velocity models on the test dataset. The developed algorithms were successfully applied to real seismic data from an oil and gas field in Western Siberia for automated near-surface model construction.

Conclusions. The set of developed algorithms, based on trained neural networks, off ers a new and effective implementation of the SWI method. It automates and significantly accelerates near-surface model construction through the processing of surface wave data, overcoming the limitations of manual methods and providing a powerful tool for seismic analysis.

Introduction. Seismic amplitude inversion enables the transition from wavefield amplitudes to the distributions of physical properties and the prediction of their propagation. However, the inversion problem is often ill-posed due to solution non-uniqueness and instability, as well as the limited frequency range of seismic data, which typically necessitates iterative optimization.

Aim. The objective of this study is to develop and test a method for impedance inversion using Generative Adversarial Networks (GAN) without the need for constructing a low-frequency model or extracting the impulse from well log data. This method aims to minimize the degrees of freedom of the inversion algorithm, relying on neural networks’ ability to extract all necessary information directly from the input data, and signifi cantly reducing the time required for predicting the propagation of acoustic properties.

Materials and methods. The study examines three model architecture scenarios for predicting pseudo-acoustic logging, each differing in the number of neural networks. Each scenario is adapted to the specifics of real data, where the number of wells available for analysis is often limited. The proposed training approach used in GANs is applied for solve model regularization and overfitting tasks. The developed method is tested on real data from a site in Eastern Siberia.

Results. The results of the new method are compared with those of the standard model-based acoustic inversion algorithm. Our method demonstrates comparable metrics in quantitative evaluation and qualitative analysis, requiring significantly less time to obtain the forecast.

Conclusion. Our method demonstrates high efficiency in using deep learning technologies to solve seismic data inversion problems and can be considered as a rapid method for acoustic inversion.