bluuebunny/crossref_metadata_2025 huggingface dataset:
New Methodology for Calculating the Impact of High Free Gas Content in the Flow on ESP Characteristics for the West Siberia Fields
Authors: Goridko Kirill Alexandrovich , Khabibullin Rinat Alfredovich , Verbitsky Vladimir Sergeevich , Shabonas Arturas Rimo , Kazakbaeva Guzel
Published: October 2021

One of the most common complications in the operation of wells with electric submersible pumps (ESP) is the presence of free gas in the produced well product. The work considers a model of ESP operation taking into account a large share of free gas in the flow obtained on the basis of bench tests and its applicability for analyzing the operation of real producing wells equipped with ESPs.

Tests of ESP5-50 (118 radial stages) with model gas-liquid mixtures in a wide range of inlet gas volume-flow rate (0-60%), inlet pressure (0.6-2.1 MPa), shaft speed (2400-3600 rpm) with simultaneous pressure measurement along the pump length and direct measuring of power at the shaft by means of motor weights were performed at the oilfield development and operation department. Mathematical model is obtained by means of regression analysis of experimentally received characteristics of ESPs on gas liquid mixtures; a simple engineering method of calculating the degradation of ESPs characteristics by flow, head and power is suggested. The experience of building similar models described in the literature was taken into account. Experimental studies and creation of a mathematical model of ESP were carried out during Kirill Goridko's PhD thesis.

As a result of the research we obtained the degradation dependencies of the pump's delivery and the head of ESP while pumping mixtures of different foam capacity, which simulate the pump operation in low and high watercut wells. The patterns of delivery and head coefficients depending on the zone (left, optimum, right) of ESP characteristic are revealed. The degradation of ESP power during pumping gas liquid mixture is clarified, which allows to calculate more accurately the specific energy consumption of well products lifting. The developed method of recalculation of the pressure and power characteristics of ESPs is implemented in the form of calculation modules designed for engineering calculations in oil production. The proposed tool has been tested on the data of the Western Siberia fields while analyzing the operation of wells with high gas content in the produced product. Calculation modules have been made publicly available.

A new simple engineering method was developed to account for the degradation of the pressure and flow and power characteristics of ESPs for low- and medium-rate wells based on a large number of benchmark studies. Оbtained degradation dependences are programmed in the form of calculation modules, which allows to analyze the operation of a large number of wells on the basis of their technological mode, as well as to propose optimization measures to change the ESP operation at a higher level.
The Choice of the Optimal Strategy for the Use of Solvents of High-Molecular Organic Deposits, Considering their Complex Composition and the Effect on the Oil Dispersion System
Authors: Guskova Irina Alekseevna , Khayarova Dinara Rafaelevna , Abzyapparova Elvira Rafaelevna
Published: October 2021

The long-term practice of operating wells producing oil rich in paraffins and asphaltenes has shown that the optimization of technologies for the removal of solid high-molecular organic deposits (asphaltene-resin-paraffin deposits) in oilfield equipment, lifting pipes and flow lines makes it possible to effectively solve the issues of improving the environmental friendliness and energy efficiency of oil production. The use of composite hydrocarbon solvents is one of the most well-known methods used to remove asphaltene-resin-paraffin deposits. Thus, to date, there is no systemic solution to this issue. This paper is aimed at discussing the provisions that determine the possible prospects for the development of an optimal strategy for the use of solvents for the removal of asphaltene-resin-paraffin deposits.
Interfacial Tension Measurements at Reservoir Conditions Using X-Ray Imaging
Authors: Pletneva Vera , Korobkov Dmitry , Kornilov Anton , Safonov Ilia , Yakimchuk Ivan , Stukan Mikhail
Published: October 2021

Interfacial tension (IFT) is one of the key parameters governing multiphase flow in reservoir. One of standard IFT measurement techniques is pendant drop shape analysis, which includes an acquisition of the drop snapshots in visible light. Hence, the method is limited by optical transparency of an external fluid. Here we present a new approach, which is free from this limitation. It uses X-rays as an illumination source and provides a number of advantages and additional opportunities in the study of fluid interface behavior. Proposed method includes a drop generation inside a uniquely designed X-ray transparent cell for high pressure and temperature (HPHT) measurements placed inside an X-ray scanner and imaging of its evolution with time till equilibrium state. Since X-ray images significantly differ from the classical optical ones, a novel algorithm was developed for accurate drop shape detection and further mathematical processing for IFT value calculation. As a result, an IFT value evolution curve for a pair of fluids is obtained. Depending on relative densities of the fluids, different experimental schemes can be implemented: pendant or rising drop.

The method was validated on various neat fluids with well-known IFT values and then was successfully applied for different real fluids systems. This work demonstrates the unique laboratory studies carried out on different liquid-fluid systems showing that the developed methodology works well at elevated pressure and temperature conditions.

The developed method unlocks the possibility for an appropriate IFT measurements in surfactant-rich oil-water systems as well as in systems near the phase transition such as gas-condensates at a wide range of thermobaric reservoir conditions and increases feasibility of HPHT measurements due to simplification of the measuring system design.
Experience of Application of Different Multiphase Metering Technologies for Cold Production and High Viscosity Oil Systems
Authors: Tonkonog Mikhail Igorevich , Kaipov Yermek Talgatovich , Pruglo Dmitry Sergeevich
Published: October 2021

Production monitoring is essential not only for fiscal applications, but also for production optimization and efficient reservoir management. So, production measurements must be both accurate and frequent enough, revealing a consistent trend of well operating parameters. This is especially important for reservoirs of complex geology, like oil rim reservoirs in poorly consolidated sandstone formations with presence of aquifer and gas cap drive. Production monitoring can be implemented with different technologies, accuracy of monitoring is however affected by different factors like gas content, viscosity and temperature of produced fluids. Paper presents pragmatic approach and analysis of applicability of different measurement technologies: compact two-phase separator and two different multiphase metering technologies applied at oil wells of Tazovskoye field operated by LLC "Meretoyakhaneftegaz", which production conditions are very challenging due to high gas volume fraction of the produced fluid, high viscosities and low temperatures.
The Interpretation Technique of Rate Transient Analysis Data in Fractured Horizontal Wells
Authors: Urazov Ruslan Rubikovich , Davletbaev Alfred Yadgarovich , Sinitskiy Alexey Igorevich , Zarafutdinov Ilnur Anifovich , Nuriev Artur Khamitovich , Sarapulova Veronika Vladimirovna , Nosova Oxana Evgenievna
Published: October 2021

This research presents a modified approach to the data interpretation of Rate Transient Analysis (RTA) in hydraulically fractured horizontal well. The results of testing of data interpretation technique taking account of the flow allocation in the borehole according to the well logging and to the injection tests outcomes while carrying out hydraulic fracturing are given. In the course of the interpretation of the field data the parameters of each fracture of hydraulic fracturing were selected with control for results of well logging (WL) by defining the fluid influx in the borehole.
The Use of Chromate Desorption Systems to Optimize the Position of the Wells Relative to the Contact Boundaries During the Development of Oil Rim Fields
Authors: Lutoev Pavel , Kuznetsov Dmitry , Nikishin Igor , Efimov Evgeny , Minakhmetov Radik , Platonov Igor , Nukhaev Marat , Kabanov Vasilii , Zaitsev Alexsandr
Published: October 2021

This paper presents a novel technology for identifying the inflow profile during the oil rim development using chromate desorption systems that makes it possible to solve one of the critical tasks related to long horizontal and multi-bottom-hole wells—optimizing the position of well relative to the contact boundaries to prevent early water breakthroughs and gas outs.
A New Approach to Simulation of Wax Precipitation During Cold Water Injection in Carbonate Reservoir of Kharyaga Oilfield
Authors: Trushin Yuri Mikhailovich , Aleshchenko Anton Sergeevich , Zoshchenko Oleg Nikolaevich , Arsamakov Mark Suleimanovich , Tkachev Ivan Vasilevich , Kruglov Dmitry Sergeevich
Published: October 2021

The paper describes a methodology for assessing the impact of wax deposition in reservoir oil during cold water injection into heterogeneous carbonate reservoir D3-III of the Kharyaga field. The main goal is to determine the optimal amount of hot water that must be injected before switching to cold water without affecting the field development. The paper presents the results of laboratory studies to determine the thermophysical properties of oil, samples of net reservoir and non-reservoir rock, as well as the results of laboratory studies to determine the conditions and nature of wax deposition in oil when the temperature and pressure conditions change. Calculations were carried out to describe the physical model of oil displacement by water of various temperatures. A series of synthetic sector model runs was performed, which includes the average properties of the selected reservoir and the results of laboratory studies in order to determine the effect of cold water injection on the development performance.
Technological Features of Associated Petroleum Gas Miscible Injection MGI in Order to Increase Oil Recovery at a Remote Group of Fields in Western Siberia
Authors: Vershinin Sergey Anatolevich , Blyablyas Alexander Nikolaevich , Golovanov Dmitriy Aleksandrovich , Penigin Artem Vitalievich , Glavnov Nikolay Grigorievich
Published: October 2021

The problem of associated petroleum gas utilization is especially urgent for fields located far from infrastructure facilities for raw gas transportation and treatment. For such fields, alternative methods of gas utilization, especially gas re-injection, are becoming relevant. The re-injection options include: injection into underground reservoir for storage (if there are reservoirs suitable for injection near the field), injection into a gas cap, if any, or injection into a productive reservoir. The latter method allows, along with solving the problem of gas disposal, to increase oil recovery. This study describes an example of miscible gas injection into the reservoir at the Chatylkinskoye field, the infrastructure assumptions which make this option a better one versus a selling option, and the features of a gas treatment and injection process.
Diagnostic Plots for Production Decline During the Transition of Oil Field Development From Depletion to Water Injection
Authors: Syrtlanov Vil , Golovatskiy Yury , Ishimov Ivan
Published: October 2021

In this paper the simplified way is proposed for predicting the dynamics of liquid production and estimating the parameters of the oil reservoir using diagnostic curves, which are a generalization of analytical approaches, partially compared with the results of calculations on 3D simulation models and with actual well production data.
The Use of Tracer Technologies for Well Monitoring with Multi-Stage Hydraulic Fracturing on Bolshetirskoye Oil Field
Authors: Krasnov Ivan , Butorin Oleg , Sabanchin Igor , Kim Vasiliy , Zimin Sergey , Pshenichniy Alexander , Toporov Alexey , Ivanoshchuk Igor , Valeev Ramil , Galimzyanov Artem , Naydenskiy Konstantin
Published: October 2021

With the development of drilling and well completion technologies, multi-staged hydraulic fracturing (MSF) in horizontal wells has established itself as one of the most effective methods for stimulating production in fields with low permeability properties. In Eastern Siberia, this technology is at the pilot project stage. For example, at the Bolshetirskoye field, these works are being carried out to enhance the productivity of horizontal wells by increasing the connectivity of productive layers in a low- and medium- permeable porous-cavernous reservoir.

However, different challenges like high permeability heterogeneity and the presence of H2S corrosive gases setting a bar higher for the requirement of the well construction design and well monitoring to achieve the maximum oil recovery factor. At the same time, well and reservoir surveillance of different parameters, which may impact on the efficiency of multi-stage hydraulic fracturing and oil contribution from each hydraulic fracture, remains a challenging and urgent task today.

This article discusses the experience of using tracer technology for well monitoring with multi-stage hydraulic fracturing to obtain information on the productivity of each hydraulic fracture separately.
Geochemical Monitoring of Formation Fluids for Reservoir Management Considering Complicating Factors in Mature Oilfields
Authors: Shipaeva Mariya Sergeevna , Nurgaliev Danis Karlovich , Zaikin Artem Aleksandrivich , Sudakov Vladislav Anatolevich , Shakirov Artur Albertovich , Abuzarovich Lutfullin Azat , Ganiev Bulat Galievich
Published: October 2021

At the present stage of the hydrocarbon production process, most of the unique and largest fields in the world are at a late stage of development. Despite the active development and policy of a decarbonised economy, the demand for liquid and gaseous hydrocarbons remains high, while of inevitably growing the number of mature fields. The Volga-Ural oil and gas province today is an old oil and gas producing region, most of the fields have already entered the final stage of development. However, through the introduction and development of new technologies for oil extraction, monitoring of production and localization of reserves, the life of the fields can be extended. One of these technologies is geochemical monitoring of well production. Its goal is to optimize the development of mature fields on the basis of promptly obtained information about the state of the wells using geochemical studies of the formation fluid, allowing timely implementation of the necessary measures. Geochemical studies allow identifying the source of fluid entering the well, determining a violation in the wellbore structure, checking the tightness of downhole equipment for separate operation, and performing an area analysis of the area development efficiency. This type of research is relevant both in giant fields with a large stock of production wells, often characterized from a geological point of view by multilayer structure, with technological complexity, packing, wear of equipment and strings, in some cases the impossibility of running gauge for research, and in fields with low depletion. The possibilities of geochemistry for solving local operational problems in wells are shown. Several hydrogeological complexes have been studied, the change in the properties of the produced water during the development process is described. The concepts of the geochemical conditions in the hydrocarbon deposits that existed earlier are changing due to the development of these objects as a dynamic system, continuous injection of different types of water into the reservoir, the use of enhanced oil recovery methods and other technogenic impact associated with the development of reserves. The digital revolution and the modern development of the industry marked the beginning of the creation of the Digital Atlas of Groundwater, the development of specialized algorithms that allow processing large amounts of data.
Optimization of the Reservoir Pressure Maintenance System in a Low-Permeability Carbonate Field
Authors: Ismagilov Ruslan Faritovich , Chernykh Irina Aleksandrovna , Chukhlov Andrey Sergeevich , Nikulin Sergey Evgenievich , Gulyaev Danila Nikolaevich , Zinurov Linar Airatovich
Published: October 2021

The investigated field is located in the Solikamsk drawdown in the northeast of the Perm Territory. The oil content level of this field is composed of Tournaisian-Famennian, Radaevsky, Radaevian, and Tula formations. This article will analysis carbonate deposits from the Tula formation using the multiwell retrospective testing (MRT) technology.

Currently, the development system has been already formed, and there is ongoing compaction drilling and targeted drawdown increase that is carried out at certain wells. A pressure support system has been formed. Before the surveys have been conducted, there was a trend in production decline, for reasons that are currently unknown. To identify the causes of production decline at the carbonate reservoir in the field, special technology was used to analysis production history data and bottom hole pressure - this technology is called multiwell retrospective testing (MRT).

Four sections were selected for further analysis, MRT was able to reconstruct the reservoir pressure variations and production coefficient at the tested well, the influence of the offset wells on the tested wells has been evaluated, along with transmissibility at the cross-well interval and well-bore skin of the tested wells.
Modified CR-Type Material Balance Model for Well Production Forecasts in Case of Well Treatments
Authors: Gubanova Anna E. , Khabibullin Bulat A. , Orlov Denis M. , Koroteev Dmitry A.
Published: October 2021

To reduce inefficient costs and environmental risks, oil companies strive to optimize the process of hydrocarbon production at all stages of field development, including geological and technical works at wells. In particular, it is important to predict fluid production with high accuracy. 3D hydrodynamic modeling is a generally accepted technique for solving this problem. It provides reliable results but requires many input data, computational resources, and time for calculations. Since the decision-making process has to be reactive, it is necessary to develop a simultaneously precise and prompt predictive instrument for quick forecasts of liquid production. The most promising tools for these purposes are proxy models based on solving the material balance equation. They adapt to the existing historical data even without PVT properties and reservoir data. Some of the most popular approaches are proxy models such as Capacitance Resistance Models (CRM).

CR-type model is a material balance-based flow model, which provides preferable transmissibility trends, the presence of sealing or leaking faults with compressibility effects in consideration, and dissipation between injector-producer pairs. It is a data-driven model with adjustable time constants and interwell connectivity parameters. Before the model tuning, all parameters must be initialized with analytical or random approximations, and then they can be found by an appropriate optimization procedure. Historical-based Capacitance Models can be applied to poorly studied fields. Besides, they give an opportunity to rapidly optimize field development strategy by making calculations with different well exploitation parameters. They only require historical data of hydrocarbon production volumes, injection profiles, and bottom-hole pressure dynamics as input data. One of the main is that properties in the interwell space are estimated approximately and considered to be constant throughout the entire development history. However, this is a weak assumption in the case of including well interventions and stimulations.

Thus, the main goal of this work is to adjust coefficients online to changes in well operation modes, introducing new wells or shut-in the existing ones. Since the governing equation includes the considered CRM improvement, users can perform optimization over different timespans, including "special" intervals. As a result, weighting connectivity parameters of the model can be depicted on a map of well interactions versus time.
Production Performance Analysis of Volga-Ural Mature Waterflood with PRIME Diagnostic Metrics
Authors: Aslanyan Artur Mihailovich , Ganiev Bulat Galievich , Lutfullin Azat Abuzarovich , Farkhutdinov Ildar Zufarovich , Garnyshev Marat Yurievich , Farakhova Rushana Rinatovna , Mustafina Alfiya Nurimanovna
Published: October 2021

The paper presents a practical case of production performance analysis at one of the mature waterflood oil fields located at the Volga-Ural oil basin with a large number of wells. It is a big challenge to analyse such a large production history and requires a systematic approach.

The main production complication is quite common for mature waterflood projects and includes non-uniform sweep, complicated by thief injection and thief water production. The main challenge is to locate the misperforming wells and address their complications.

With the particular asset, the conventional single production analysis techniques (oil production trend, watercut trend, reservoir and bottom-hole pressure trend, productivity trend, conventional pressure build-up surveys and production logging) in the vast majority of cases were not capable of qualifying the well performance and assessing of remaining reserves status. The performance analysis of such an asset should be enhanced with new diagnostic tools and modern methods of data integration.

The current study has made a choice in favor of using a PRIME analysis which is multi-parametric analytical workflow based on a set of conventional and non-conventional diagnostic metrics. The most effective diagnostics in this study have happened to be those are based on 3D dynamic micro-models, which are auto-generated from the reservoir data logs.

PRIME also provided useful insights on well performance, formation properties and the current conditions of drained reserves which helped to select the candidates for infill drilling, pressure maintenance, workovers, production target adjustments and additional surveillance.

The paper illustrates the entire PRIME workflow, starting from the top-level field data analysis, all the way to generating a summary table containing well diagnostics, justifications and recommendations.
Short-Term Forecasting of Well Production Based on a Hybrid Probabilistic Approach
Authors: Evseenkov Anton Sergeevich , Kuchkildin Denis Kamilevich , Krechetov Konstantin Igorevich , Ospishchev Semyon Alexandrovich , Kotezhekov Victor Sergeevich , Yudin Evgeny Viktorovich
Published: October 2021

The presented article is dedicated to creation and testing of probabilistic ensemble computational tool for operational forecasting of well production in short term (STF). The ensemble consisted of models based on such physical and mathematical tools as: the equation of non-stationary filtration, material balance, Darcy's law and machine learning models. After calculations by each model, their forecasts are combined into a single ensemble forecast. The hybrid approach is based on the Monte Carlo method on Markov chains as a separate probabilistic model using Bayes’ formula. In this case, statistical weights of each model (the degree of confidence in each model) is determined in the form of a probability distribution based on the reliability of previously performed forecasts. The test results presented in this article were obtained on the real field data. The obtained forecasts of individual models and the ensemble were compared to real data. Real data tool usage analysis showed that the proposed approach gives a small error in comparison with actual measurements. Efficiency of calculations allows to automatically adapt the model to the entire well production history (several hundred wells) within a few hours.
Intelligent Production Monitoring with Continuous Deep Learning Models
Authors: Gryzlov Anton , Safonov Sergey , Arsalan Muhammad
Published: October 2021

Monitoring of production rates is essential for reservoir management, history matching, and production optimization. Traditionally, such information is provided by multiphase flow meters or test separators. The growth of the availability of data, combined with the rapid development of computational resources, enabled the inception of digital techniques, which estimate oil, gas, and water rates indirectly. This paper discusses the application of continuous deep learning models, capable of reproducing multiphase flow dynamics for production monitoring purposes. This technique combines time evolution properties of a dynamical system and the ability of neural networks to quantitively describe poorly understood multiphase phenomena and can be considered as a hybrid solution between data-driven and mechanistic approaches. The continuous latent ordinary differential equation (Latent ODE) approach is compared to other known machine learning methods, such as linear regression, ensemble-based model, and recurrent neural network.

In this work, the application of Latent ordinary differential equations for the problem of multiphase flow rate estimation is introduced. The considered example refers to a scenario, where the topside oil, gas, and water flow rates are estimated using the data from several downhole pressure sensors. The predictive capabilities of different types of machine learning and deep learning instruments are explored using simulated production data from a multiphase flow simulator.

The results demonstrate the satisfactory performance of the continuous deep learning models in comparison to other machine learning methods in terms of accuracy, where the normalized root mean squared error (RMSE) and mean absolute error (MAE) of prediction below 5% were achieved. While LODE demonstrates the significant time required to train the model, it outperforms other methods for irregularly sampled time-series, which makes it especially attractive to forecast values of multiphase rates.
Selecting and Modifying Multiphase Correlations for Gas-Lift Wells Using Machine Learning Algorithms
Authors: Gorbachev Roman , Gubaev Andrey , Lubnin Alexander , Chorny Alexey , Kurbanov Vasif
Published: October 2021

In the conditions of the development of the oil fields of the Cuu Long Basin in the continental shelf of the Republic of Vietnam, in the absence of downhole gauge systems, the urgent task is improving the accuracy of the calculation of bottomhole pressure in the producing wells based on the operation modes and construction.

The aim of the paper is to create tools for selecting and modifying the correlation of multiphase flow most suitable for the development of a particular group of fields, as well as to develop a tool to implement effective management of the modes of operation of gas-lift wells by choosing the optimal gaslift injection rate.

Based on data from 814 instrumental measurements in wells with different construction, liquid flow rate, watercut, GOR and gaslift injection, the calculation of bottom hole pressures was made.

The calculated and actual bottomhole pressures were compared with five correlations of multiphase flow, the most suitable correlations were determined and modified, including using machine learning methods, which helped to significantly improve the convergence of calculated and actual bottomhole pressures.

On the basis of the newly modified correlation, a calculation of bottom hole pressure (BHP) in each production well was made, the calculation of the change in bottomhole pressure when changing the operating modes of wells has been implemented.

For the field group of the Cuu Long Basin, it was revealed that with the increase in watercut in the producing wells significantly reduces the efficiency of the gas-lift method of operation. This effect is not reflected in the widespread correlations of multiphase flow, which does not allow to use the results of calculations without making additional edits.

A way to adapt the calculation values to instrumental measurements has been implemented, one of the known correlations has been modified and used in the forecast of changes in bottomhole pressure after changes in operating modes of wells throughout the well stock.
Integrated Field Development Modeling of Block in Giant Oil Reservoir
Authors: Bogachev Kirill , Zagainov Aleksandr , Piskovskiy Evgeny , Moshina Iuliia , Grishin Aleksei , Muryzhnikov Anton , Gatin Aydar , Korostelev Nikita
Published: October 2021

The creation and matching of an integrated field model including a model for part of a giant field, well models and surface network model is considered here.

The integrated model was created using an innovative method of solving a unified system of equations that cover all the physical processes in the reservoir-well-surface network system; no integrator software was involved.

The project involves a history-matched dynamic model covering part of a giant field, a surface network layout and well constructions with the subsurface equipment parameters. These data were fed to a single software product to create a digital twin which would allow simultaneous work with both the reservoir and the network.

The approach enabled quick creation and matching of an integrated model with a lot of wells which can create forecasts for various operation modes and estimate the base case production for the infrastructure in place, as well as offers an option to connect new project wells to the current surface network.
Hierarchy of Integrated Models of Varying Detail to Solve Problems at Different Stages of Gas Condensate Projects Development
Authors: Varavva Artem Igorevich , Apasov Renat Timergaleevich , Badgutdinov Ruslan Rustamovich , Yamaletdinov Ayrat Flyurovich , Koryakin Fedor Andreevich , Sandalova Ekaterina Evgenevna , Samolovov Dmitriy Alekseevich , Bikbulatov Salavat Miniahmetovich , Nekhaev Sergey Sergey
Published: October 2021

This study makes an attempt to generalize the integrated modeling tools used by the authors in practice on the basis of the following criteria: the volume of the initial data, the integration mechanism, constraints and assumptions. Various types of integrated models are compared with each other, the need for their application is analyzed, they are connected at various stages of the project development and by the tasks solved at this stage. It also describes the challenges that the authors encountered when working with integrated models of various levels of detail, approaches to their solution, and the lessons learned.
Generation of a Probabilistic Facial Model on the Basis of Lithology Logs, Well Logs, Seismic Data and Existing Methods of Machine Learning and Classification
Authors: Zaitsau Henadz , Shumilyak Valeri , Konyushenko Alexander
Published: October 2021

The main topic of an article is machine learning and classification (neural net) use for prognostic lithological model creation. Moreover, research preceding stages such as attribute analysis, seismic inversion, seismogeological modeling and briefly the results of lithological and petrophysical investigations are described in this art
Seismic Data Analysis for Well Performance and Production Data Forecast: Massive Low-Relief Gas Reservoir Case Study
Authors: Gorlanov Aleksei Anatolyevich , Vorontsov Dmitrii Yurevich , Schetinin Aleksei Sergeevich , Aksenov Aleksandr Ivanovich , Ovchinnikova Diana Gennadyevna
Published: October 2021

In the process of developing massive gas reservoirs, gas-water contact (GWC) rise is inevitable, which leads to water-breakthrough in wells and declining daily gas production. Drilling horizontal sidetracks and new horizontal wells helps to maintain target production levels.

The direction of drilling a horizontal well section largely determines its efficiency. In complex geological conditions, a detailed analysis of seismic data in the drilling area helps to reduce drilling risks and achieve planned starting parameters.

The integration of seismic data in geological models is often limited by poor correlation between reservoir properties from wells and seismic attributes. Flow simulation models use seismic data based on the assumptions made by the geological engineers.

The study uses a cyclic approach to geological modeling: realizations include in-depth analysis of seismic data and well performance profiles. Modern software modules were used to automatically check the compliance of the geological realization with the development history, as well as to assess the uncertainties. This made it possible to obtain good correlation between well water cut and seismic attributes and to develop a method for determining the presence of shale barriers and "merging windows" of a massive gas reservoir with water-saturated volumes.
Comprehensive Analysis of the Geological and Geophysical Data in the Study of the Upper Miocene Turbidite Systems of the Nam Con Son Basin, Vietnam
Authors: Kurianova Mariia , Birkle Ekaterina , Egorkina Tatiana , Koltsov Sergey
Published: October 2021

The article considers the approaches to the G&G data interpretation used in the Branch Office of Gazprom International in Saint Petersburg (hereinafter referred to as "GPEPI") when studying the geology aspects of turbidite deposits. This approach is showcased on one of the Upper Miocene deposits of the Nam Con Son Basin in Vietnam, and a conclusion is drawn about the possibility of using this complex technique in the study of sand bodies of any genesis.
Efficiency of Using a Proxy Model for Modeling of Reservoir Pressure
Authors: Yudin Evgeniy Viktorovich , Markov Nikolay Sergeevich , Kotezhekov Viktor Sergeevich , Kraeva Svetlana Olegovna , Makhnov Andrei Vasilyevich , Trubnikov Nikita Pavlovich , Gorbushin Leonid Arkadevich
Published: October 2021

The presented paper is devoted to the development and testing of a computational tool for assessment of the reservoir pressure and prompt generation of the pressure maps of collectors. The tool is based on a proxy model that allows to solve the two-dimensional diffusion equation for unsteady liquid filtration using the boundary element method. To expand the applicability of the proxy model, an algorithm for automated parameter adaptation was developed. This algorithm allows to exclude knowingly unreliable data or low-quality data from modeling. This is achieved due to analyzing the correlation between the injection, production and bottom-hole pressures for the entire well stock over the history of the reservoir development. In addition, this paper describes an approach to modeling two-phase oil and gas filtration based on the use of pseudofunctions. This approach considers the influence of gas on the oil filtration process. The use of pseudofunctions allows us to linearize the diffusion equation for two-phase filtration and to solve it using the boundary element method in the same manner as for the case of oil filtration without gas. To demonstrate the results of the proxy model validation, examples of its use for generating the pore pressure maps for two real collectors are given. The average values of the reservoir pressure at the wells calculated using the proxy model are compared with the results of the corresponding well tests and with the traditional isobar maps. The analysis showed that the average deviation of the proxy model from the real reservoir pressures is less than 10%.
Solving the Inverse Problem of Geomechanical Monitoring to Improve the Efficiency of Field Development
Authors: Krasnikov Artem Alexandrovich , Melikov Ruslan Fuadovich , Korelskiy Evgeniy Pavlovich , Petrakov Yuriy Anatolyevich , Sobolev Aleksey Evgenievich
Published: October 2021

The purpose of geomechanical monitoring at mineral deposits, including oil and gas, is to control the state of the rock mass, forecast possible risks and complications at all stages of the field's life: reservoir and caprock integrity failure, violation of the integrity of drilling and system of well completion, infrastructure facilities.

The paper suggests approaches to the organization of a geomechanical monitoring system based on observations of displacements and deformations of the ground surface (or seafloor) during the development of reservoir and target interval.

There are analytical and numerical approaches have been tested on simple models with pore pressure changes, considering the heterogeneity of elastic-strength properties.
Artificial Neural Network as a Method for Pore Pressure Prediction throughout the Field
Authors: Mylnikov Danila , Nazdrachev Viktor , Korelskiy Evgeniy , Petrakov Yuriy , Sobolev Alexey
Published: October 2021

Geomechanical model construction is an essential part of field development processes planning. Building a correct pore pressure model is one of the key tasks within the process of geomechanical model construction. The traditional approach to pore pressure modeling in oil and gas industry is based on the empirical analytical models usage. This approach has a number of disadvantages, which often lead to the constructed pore pressure model to be incorrect. The authors highlight two most significant disadvantages of the traditional approach: 1) a priori discrepancy between the empirical model and fundamental physical laws; 2) the impossibility of selecting such a combination of parameters of the standard analytical model, for which the resulting pressure corresponds to the entire set of actual field data (pore pressure measurements).

This paper proposes a methodology for assessing the pore pressure distribution across the field, based on the usage of neural network technology. This approach potentially eliminates both of the above disadvantages from the pore pressure model building.
On the Use of Indentation for Studying Rock Properties
Authors: Stsiapankin Ihar , Khaletski Andrei , Hutman Raman , Tkachou Viktar
Published: October 2021

It was developed the method for determining the strength of material without breaking the test sample. The essence of the method is to determine the strength characteristics of the rock by pressing into the variable cross-section indenter. The practical significance lies in the possibility of performing an express analysis of the strength of rocks on small-sized samples - 3 mm or more, for example, using the particles of landslide cuttings from unstable intervals when drilling wells; there is no need for the preparation of reference material; the simplicity and availability of the equipment used and high accuracy of the results obtained is also important. The developed method has no analogues and is patented in the patent offices of the Republic of Belarus and the Russian Federation.
Risk Management Approach: Drilling and Completion Projects
Authors: Ruzhnikov Alexey , Yurtaev Viktor
Published: October 2021

This manuscript describes the approach in the risk management developed and implemented while operating 21 drilling rigs on 13 fields simultaneously in the Middle East, which resulted in 40% reduction of non-productive time. Well construction process requires a lot of attention on different levels and from different sides to ensure trouble-free execution. The bigger the volume of work, the higher the chance of a costly mistake.

The risk management process was split in several steps, where different levels and divisions are involved. The Planning stage starts at engineering level and associated risk review goes to a level of Division Supervisor for every well, when special tools were developed to focus on potential high impact events. The Execution stage was covered by a set of Critical Activity reviews and Standard operation procedures, focusing on operations with highest risks or highest benefits. Further at the Evaluation stage every well was analyzed following the developed workflow, and further all obtained knowledge shared with every team member via custom designed dashboards.

Shortly after initial steps were taken under the new risk management approach, one of main KPI – non-productive time (NPT) – started to decrease and dropped by 5% within one quarter. Further tuning of the process allowed to decrease NPT by over 40% with continuous positive trend. One of the main contributors is the re-focusing on the prevention measures during planning stage, which avoid non-conformance events with high impact. Simultaneously the approach unified the practices of different divisions and remove misalignment on most of the technical issues and questions. Additionally, it decreased the workload of the key field personnel, as reduced NPT gives more time to focus on continuous rig performance improvement.
Adaptation of Capillary String for the Surfactants Delivery into a Gas Condensate Well and Optimization of its Operation Using Dynamic Multiphase Flow Simulator
Authors: Solovev Daniil Yurievich , Epryntsev Anton Sergeevich , Eliseev Petr Ilich , Yamov Andrey Gennadievich , Nerodenko Yamov Grigorievich , Guseynov Elkin Bakirovich , Bobrov Vladimir Alexandrovich
Published: October 2021

The studied productive formation of gas condensate field is at the stage of declining production. The inflow of bottom water due to the rise of the GWC and the design features of horizontal wells (large tubing and liner diameters) create the prerequisites for the development of a liquid loading of wells. This necessitate the optimization of the existing method of liquid unloading by dosing surfactants into the annulus.

In order to increase the efficiency of well treatment with a foaming agent, the use of a surfactant injection system through a capillary string suspended inside a tubing is considered. The use of this system allows to increase the speed and depth of surfactant delivery, use the potential of the well by simultaneous work in tubing and annulus during significant watering period (water flow rate: 50 and more m3 / day), reduce reagent losses associated with retention on the casing walls, and reduce the required consumption of surfactant.

The capillary string for the pumping surfactant is applicated to ensuring the stable operation of gas condensate wells during liquid loading. But today there are not ready-made applied solutions for correctly accounting surfactant action in unsteady flows conditions in the well.

The paper presents the substantiation and analysis of the capillary string introduction into the well for the pumping surfactant using specialized software. In the course of work, the main analysis tool is the dynamic modeling of multiphase flows in the conditions of steady and unsteady processes in wells. This approach use is aimed at determining the optimal depth and diameter of capillary, the required consumption and concentration of surfactant, the rate of its delivery to the bottomhole, and the liquid removal efficiency from the horizontal wellbore.
Method for Determine Optimal Parameters of Gas Field Development System
Authors: Apasov Renat Timergaleevich , Perevozkin Igor Vladimirovich , Badgutdinov Ruslan Rustamovich , Bazhenov Dmitriy Yurievich , Nekhaev Sergey Aleksandrovich , Varavva Artem Igorevich , Koryakin Fedor Andreevich , Samolovov Dmitriy Alekseevich , Sandalova Ekaterina Evgenievna , Yamaletdinov Ayrat Flyurovich
Published: October 2021

The request for optimization of development system parameters, well designs and the ground facility architecture is permanent task during the development of hydrocarbon fields. Decrease in the quality of oil and gas reserves, development of fields in difficult environment conditions and in the Arctic, oil and gas prices development lead to an increase in the sensitivity of new field’s development profitability from the parameters of the development system and field facilities.

Infrastructure of a field for the development of a gas field is associated with significant capital costs, both for the construction of wells and local infrastructure facilities, and for the construction of facilities for the preparation and transportation of gas. Therefore, one of the main tasks in the design of gas field development is the calculation of the optimal parameters of the development system - the number of wells and gas production plateau. Now the most well-known approaches to solving this problem are the calculation of different development variants using integrated numerical hydrodynamic models (Apasov et.al., 2018), taking into account all the features of the field under consideration or using analytical models based on the fundamental principles of filtration theory and development experience.

In such conditions, when solving optimization problems, it is necessary to take into account all the components of the production system (Khasanov et.al., 2020), otherwise it can be an incorrectly assessment of the economic effect of optimization and face the unprofitability of the developed design solutions. For most oil fields, the interinfluence of the reservoir part of the field, well lifts and the infrastructure is relatively weak, therefore, these parts can be optimized separately. When designing the development of fields with oil rims and gas fields, especially multilayer ones, optimization requires searching for a global optimal solution, investigating the existence and uniqueness of such a solution - on the models describing the field and interaction of the infrastructure, well lifts and the reservior part.
Forecasting the Water Flooding for the Production Wells of a Gas Condensate Field with a Fractured Reservoir Type
Authors: Gladkov Pavel Dmitrievich , Zheltikova Anastasiia Vladimirovna
Published: October 2021

As is known, fractured reservoirs compared to conventional reservoirs have such features as complex pore volume structure, high heterogeneity of the porosity and permeability properties etc. Apart from this, the productivity of a specific well is defined above all by the number of natural fractures penetrated by the wellbore and their properties. Development of fractured reservoirs is associated with a number of issues, one of which is related to uneven and accelerated water flooding due to water breakthrough through fractures to the wellbores, for this reason it becomes difficult to forecast the well performance.

Under conditions of lack of information on the reservoir structure and aquifer activity, the 3D digital models of the field generated using the hydrodynamic simulators may feature insufficient predictive capability. However, forecasting of breakthroughs is important in terms of generating reliable HC and water production profiles and decision-making on reservoir management and field facilities for produced water treatment. Identification of possible sources of water flooding and planning of individual parameters of production well operation for the purpose of extending the water-free operation period play significant role in the development of these reservoirs.

The purpose of this study is to describe the results of the hydrochemical monitoring to forecast the water flooding of the wells that penetrated a fractured reservoir on the example of a gas condensate field in Bolivia. The study contains data on the field development status and associated difficulties and uncertainties. The initial data were results of monthly analyses of the produced water and the water-gas ratio dynamics that were analyzed and compared to the data on the analogue fields. The data analysis demonstrated that first signs of water flooding for the wells of the field under study may be diagnosed through the monitoring of the produced water mineralization - the water-gas ratio (WGR) increase is preceded by the mineralization increase that may be observed approximately a month earlier. However, the data on the analogue fields shows that this period may be longer – from few months to two years.

Thus, the hydrochemical method within integrated monitoring of development of a field with a fractured reservoir could be one of the efficient methods to timely adjust the well operation parameters and may extend the water-free period of its operation.