DOI: 10.24412/2076-6785-2024-3-20-25
Abstract
This paper presents the results of research on the substantiation of the oil-saturated volume of the deposit, represented by low-permeability reservoirs, of the oil-saturated reservoir of the US2 Tyumen formation, using the example of a field within the Salymsky district of the Sredneobskaya oil and gas region. One of the main parameters characterizing the area and volume of the deposit is the calculation level. The reference level is the contact separating the water-saturated section from the productive one, which characterizes the entire oil-saturated volume of the pore space of the rock.
In deposits with low-permeability reservoirs, it is often problematic to reliably determine the oil-saturated volume of rocks, due to the presence of only oil-saturated tributaries in such facilities during testing and operation, both in the arch and in the slope part of the deposit, without a single-phase inflow of reservoir water. In this regard, to perform the calculation of reserves in such facilities, a conditional calculation level (CCL) is taken according to the lowest established mark of the sole of the oil-saturated reservoir, or according to the sole of the perforation interval. At the same time, the volume of the pore space below the received contact is not included in the calculation of reserves, even if there is no single-phase inflow of reservoir water.
During the analysis of geological, geophysical, petrophysical and operational data, results were obtained showing that deposits composed
of low-permeability reservoirs represent a mixed hydrodynamic oil-water system, without oil-water contact.
Materials and methods
Data on the geological structure of the formation, including the sedimentation model, intra-stratum correlation and distribution of filtration and reservoir properties by area and section. Data on the operation of producing wells. Detailing the geological structure, determining the characteristic features of the formation section.
Keywords
reserves calculation, tyumen formation, achimov formation,
low-permeability reservoirs, counting level, CCL, geophysical studies of wells, oil and water contact
DOI: 10.24412/2076-6785-2024-3-13-18
Abstract
The article is devoted to the study of the correlation between a complex of Trace Elements (TEs) identified in oils of large fields of the Khanty-Mansi Autonomous Region (KMAO) of the West Siberian oil and gas basin (OGB), with the composition of the earth’s crust at different levels - upper, lower and middle. Based on the results of the study, additional possible indicators for predicting sources of oil and gas in the deep horizons of the sedimentary cover were identified, which could help increase the predicted resources.
Materials and methods
A quantitative comparison of the contributions of different components of the earth’s crust - lower, middle and upper, as well as biota to the trace elements of oils was carried out based on correlation analysis. For a similar project, the author used analytical materials from many researchers obtained by inductively coupled plasma mass spectrometry (ICP-MS) (R.P. Gottikh, B.I. Pisotsky et al., Yu.N. Fedorov, K.S. Ivanov, Yu.V. Erokhin, A.V. Maslov, Yu.L. Ronkin, etc.).
Keywords
large deposits, trace element composition of oils, correlation coefficients, continental crust, biota, Western Siberia
DOI: 10.24412/2076-6785-2024-3-10-13
Abstract
The article supplements and systematizes the main geological and geophysical factors affecting the formation of large accumulations of oil and gas. Based on a critical analysis of the published material by Russian and foreign authors and a generalization of factual material on 26 of the world’s largest deposits, the relationship between the size of reserves and the geological parameters of the deposit is investigated.
Quantitative and qualitative estimates of predictive geological and geochemical factors have been determined.
Materials and methods
Materials on 26 largest oil and gas fields in the world were used. The quantitative and qualitative relationships of the size of oil and gas reserves with geological and geochemical characteristics (field area, filtration and reservoir properties of reservoir rocks, composition and thickness of fluid seals, oil and gas generation potential, etc.) are analyzed.
Keywords
oil, gas, large accumulations, reserves, resources, megareservar, favorable factors, forecast criteria
DOI: 10.24412/2076-6785-2024-4-16-21
Abstract
Carbonate reservoirs, as a rule, are characterized by heterogeneity of structure and filtration and reservoir properties. In this case, the zones with the improved filtration and reservoir characteristics are primarily involved in exploitation. In this regard, during the development process there is a need to replenish the resource base of the field and maintain production levels.
The article presents the results of developing a solution to this problem using the example of an oil field in the Lower Permian carbonate reservoirs of the northeastern part of the Timan-Pechora oil and gas province. Firstly, improved filtration and reservoir properties zone was identified within the parts of the field not involved in exploitation. Secondly, objects for additional exploration in complexes that are productive in the area of the studied have been substantiated. In addition, the article provides a brief geological overview of the study area and productive oil and gas complexes, and also substantiates the heterogeneity of the structure and properties of reservoirs.
Materials and methods
The basis for the study was the results of analysis of core and thin sections, interpretation of geophysical wells logging, wells testing, as well as interpretation of seismic survey materials. Using this data in specialized software, a three-dimensional geological model was built, on the basis of which promising improved filtration and reservoir properties zones were identified.
Keywords
carbonate reservoirs, reservoir properties, Dunham classification, fractures, organogenic buildings, additional exploration,
Timan-Pechora oil and gas province
DOI: 10.24412/2076-6785-2024-4-12-15
Abstract
In the article, by summarizing the data and their critical analysis, the typification of the processes of formation of mega-reservoirs of oil
and gas in the sedimentary cover of oil and gas basins in both traditional and unconventional reservoirs, including low-pore shale formations, accumulations with hard-to-recover reserves, reservoirs of decompacted basement ledges and other types of geological structures.ý
Materials and methods
Analytical and scientific data base on the geological features of hydrocarbon accumulations with gigantic and unique reserves in various oil and gas basins of the world. Analysis and comparative assessment of the qualitative features of the confinement of large-scale accumulations of hydrocarbons to certain natural objects.
Keywords
mega-reservoirs, oil and gas fields, scale of accumulations, reservoirs, shale formations
DOI: 10.24412/2076-6785-2024-4-24-27
Abstract
Gas production by horizontal wells from reservoirs with hard-to-recover reserves is significantly growing. Such objects have a complex geology; there are many development control methods to determine the rate of reserve withdrawal and find the potential for production increase. An important part of monitoring is determining the inflow profile. The use of fiber optic sensors allows not only to localize producing intervals in the field, but also to evaluate changes of production inflow profile in real time. The paper shows the results of online monitoring, clearly showing the information content of fiber optics..
Materials and methods
Algorithms for online monitoring of the inflow profile using distributed fiber optic sensors, mathematical determination of the inflow profile using the relative temperature coefficient.
Keywords
fiber optics, online monitoring, horizontal wells, temperature logging, inflow profile, gas
DOI: 10.24412/2076-6785-2024-4-28-31
Abstract
The problem of well wall stability has been and remains relevant. The constant change of impact objects in terms of depth, lithology, and thermobaric conditions requires improved understanding of the processes and mechanisms of stabilization of the borehole. Knowledge on the physical and chemical interactions occurring in the borehole-rock system is developing and deepening. These dynamic processes require constant improvement of equipment, well construction technology and the drilling fluids used.
Materials and methods
Materials:
• production data on well drilling. An incident related to the seizure of an operational column being lowered into the well;
• the decision to drill the side barrel;
• preparation for drilling a horizontal shaft on a hydrocarbon-based solution.
Methods: Analysis of production data, taking into account the subsequent use of hydrocarbon-based solution for drilling the horizontal end of the side shaft.
Keywords
borehole stability, terrigenous rocks
DOI: 10.24412/2076-6785-2024-3-41-48
Abstract
Well tests are an important tool for determining the reservoir properties, but for gas and gas condensate reservoirs they are one of the tools for reliable determination of the well productivity factor in the dynamics of operation and the influence of technogenic fractures of multistage hydraulic fracturing on it, both as a tool for flow stimulation and increasing hydrocarbon yield of the reservoir. In this regard, the issue of reliable assessment of all operating parameters of the well from the position of the amount of resources invested in it is particularly relevant nowadays – the widespread use of high-precision digital solutions. In addition to making operational decisions on well operation management, the strategic goal of well testing in the system of field geophysical control is to obtain information that allows, in conjunction with other geological and field data, to form reliable views of the system “productive formation - fracture – well”, and to provide detailed digital models of the field for monitoring field development and refining the development strategy.
The article presents an example of multidisciplinary interaction between specialists in hydraulic fracturing, geomechanical modeling, interpretation of field-geophysical and wells testing, laboratory studies of hydraulic fracturing fluids and materials, as well as specialists in field development for reliable determination of geometric and conductive characteristics of technogenic fractures and their contribution, using the example of one of the horizontal gas-condensate wells in an East Siberian field.
Materials and methods
• The article was written using data of field geophysical studies, engineering reports on hydraulic fracturing, results of interpretation of noise and thermometry, as well as analysis of laboratory studies on fluids and materials for hydraulic fracturing at a horizontal well in the East Siberian field.
• Interpretations of gas-dynamic studies of wells with fracturing of one of the gas condensate fields, by summarizing and analyzing the results of fracturing designs, laboratory studies of fracturing fluids and proppants, geomechanical modeling and taking into account the results of determining the flow profile.
Keywords
hydrodynamic studies of wells, conductivity, technogenic fracture, horizontal well, multistage hydraulic fracturing
DOI: 10.24412/2076-6785-2024-3-30-34
Abstract
The article presents an approach for selecting the optimal type and number of autonomous inflow control devices (AICD) for the development of oil and gas deposits using multivariate hydrodynamic modeling.
According to the results of multivariate modeling, it was noted that the optimal option for completing a well with an AICD according to the criterion of accumulated production and accumulated discounted net income (NPV) varies depending on the bottom-hole pressure, and vice versa,
the optimal amount of AICD depends on the selected bottom-hole pressure.
The advantage of the proposed approach is that when selecting the layout of wells, various options for completion with AICD are modeled,
the volume of produced products and its dependence on the downhole pressure are taken into account, together with the economic component, the best completion option is determined from the point of view of economic efficiency.
For calculations, a software package was used that allows segmentation and calculation of wells with inflow control devices (developed at “RN-BashNIPIneft” LLC).
Materials and methods
Materials: characteristics of inflow control devices, sector hydrodynamic model.
Methods: analysis of the results of multivariate hydrodynamic modeling.
Keywords
inflow control device, sector hydrodynamic model, multi-segment well, oil and gas field
DOI: 10.24412/2076-6785-2022-8-87-92
Abstract
This article discusses an engineering approach to substantiate the optimal mass of injected proppant for horizontal wells with multi-stage hydraulic fracturing.
The object of study is a classic low-permeability reservoir with permeability characteristic of the area and the use of multi-stage hydraulic fracturing technology to bring reserves into development. The volumes of proppant injected into the reservoir at each stage of hydraulic fracturing are determined empirically.
In the course of the work, an approach was selected based on static analysis and averaging of data from a large volume of hydraulic fracturing.
In this work, a system of engineering justification of the maximum mass of proppant injected into the reservoir has been developed and the economic profitability limit of increasing the volume of fractures has been established.
Materials and methods
The experience of hydraulic fracturing at the field was summarized, the optimal proppant mass was substantiated to achieve the best TEC of wells, the actual hydraulic fracturing operations performed at the field were studied and analyzed, the dependences of the fracture geometry parameters on the proppant mass were established, allowing to correctly model the fracture parameters and the best parameters for various zones were determined saturation of the object according to technical and economic indicators.
Keywords
low permeability, multi-stage hydraulic fracturing, horizontal well, proppant
DOI: 10.24412/2076-6785-2022-8-82-86
Abstract
“RN-Nyaganneftegaz” JSC owns the license for oil production at the Em-Egovsky and Kamenny license blocks of Krasnoleninskoye oil and gas condensate field with unique reserves.
To date, 61 % of oil is produced from VK1–3 reservoir (vikulovskaya formation), and the volume of current recoverable reserves is 34 %
of the field’s total reserves. About 70 % of the vikulovskaya formation reserves are concentrated in the undeveloped edge zones at lower regions of the reservoir structural top, and they remain the main source for maintaining oil production.
Materials and Methods
This paper provides an overview of the drilling and development experience horizontal wells and multilateral wells, as well as well completion technologies applied for effective development of VK1–3 reservoir edge zones within Kamenny license block, which is a testing ground for pilot projects.
Keywords
drilling, development, edge zones, under-saturated reservoir, horizontal wells, multi-lateral wells
DOI: 10.24412/2076-6785-2022-8-76-80
Abstract
The paper considers an approach to the development of a unique field, which reserves are characterized by significant heterogeneity,
low permeability, abnormally high reservoir pressure. According to the geological characteristics, the reserves are hard to recover.
The strategy selection for full-scale development is planned to be made based on the results of technology testing at the sites of pilot works.
The paper proposes an approach to stage-by-stage planning “from simple to complex”, which allows risks mitigation during the implementation of work and reducing decision-making time.
Materials and methods
The justification of the pilot sites of the field under consideration
is given, tested technologies are selected. A detailed research program is developed, including all advanced methods for tight reserves. A strategy for the development of reserves is formed, key points
for obtaining information are identified.
Keywords
tight reserves, low permeability, pilot project
DOI: 10.24412/2076-6785-2022-8-70-74
Abstacrt
Tight reserves are characterized by unfavorable conditions for recovery from the position of oil properties or conditions of occurrence (concentrated in deposits of low-permeable reservoirs). At the moment, production is carried out mainly from traditional reservoirs, but as a rule, it is complex reserves that provide the main increase in the resource base of oil companies. The development of tight reserves requires the use of new technologies and significant capital investments. Deposits of unconventional reservoirs are characterized by high variability of geological feature and formation reservoir properties depending on the region, which dictates the need to develop an individual approach to their development.
The authors of the article, using the example of oil field located in the Arctic zone of Russian Federation, consider an approach to the development of technological solutions for the development of a tight reserves characterized by low permeability, high heterogeneity and the presence of abnormally high reservoir pressure.
Materials and methods
The analysis of production experience from tight reserves is carried out, the key aspects of the development of low-permeability reservoirs are identified. An approach to testing formation hydraulic fracturing technologies, the development of well completion for multistage formation hydraulic fracturing is given. Potentially effective agents for the development of tight reserves are identified, a program of laboratory studies is created to remove uncertainties.
Keywords
tight reserves, low permeability, formation hydraulic fracturing
DOI: 10.24412/2076-6785-2022-8-66-69
Abstract
At the late stage of field development, there is a decrease in production volumes compared to the design capacity of the infrastructure, which leads to the risks of liquid accumulation in the elements of the “formation – well –plume system”. To eliminate potential problems, it is important to identify the places of fluid accumulation in a timely manner and plan measures to ensure the stable operation of pipelines [3, 4].
Materials and methods
The article discusses the operation of the gas collection network with parameters corresponding to typical conditions for deposits in the final period of the development of the object.
The obtained results can be applied to substantiate the implementation of technological measures in the fields.
Keywords
gas field management, gas production, production engineering, dynamic modeling, technological regime
DOI: 10.24412/2076-6785-2022-8-60-64
Abstract
The management of several reservoirs by a single grid of wells does not always allow the correct accounting of hydrocarbon production.
The well-known and most used production redistribution methods do not take into account the component-by-component distribution of produced hydrocarbons. Methods mainly used are based on formation conductivity and net oil pay of the zone. Therefore, there is a practical need for an analytical tool that would be based on reliable and available data and could sufficiently and efficiently solve the problems associated with the separation of produced fluids.
Materials and methods
A methodology developed on the basis of combining existing tools to enhance the ultimate oil recovery by determining the containment area of residual reserves based on the analysis and revision of field data.
Keywords
redistribution of production, containment area of residual reserves, multilayer formation, accountability of reserve recovery
DOI: 10.24412/2076-6785-2022-8-53-59
Abstract
The article describes approaches to the implementation of the integrated strategy of “NK “Rosneft” PJSC (Company) in the field of geological exploration, preparation for the bringing into development of a large project (Project) located in the Arctic zone of the Russian Federation, at a considerable distance from infrastructure facilities. Predominantly, the hydrocarbon potential of the assets under consideration is associated with reserves belonging to the category of tight reserves. Their development requires the application and development of modern technologies in related fields – geology, seismic exploration, drilling, geophysics, well survey, development.
Materials and methods
Specialized methods of field geophysics, core and reservoir fluid studies are applied to ensure the effective development of tight deposits. Based on the results of the conducted research, complex geological, petrophysical and geomechanical models are constructed that allow implementing a targeted approach to the development.
Keywords
tight reserves, pilot project, infrastructure
DOI: 10.24412/2076-6785-2024-4-34-39
Abstract
In this paper are presented the results of calculations using hydrodynamic models carried out to study the behavior of the dynamics of the gas oil ratio during the development of an oil reservoir without maintaining reservoir pressure or with incomplete reservoir pressure maintenance.
It is shown that under conditions of incomplete compensation of reservoir pressure, depending on geological factors, the gas oil ratio can exceed the initial gas solubility by one or several orders of magnitude in case of developing a saturated oil reservoir.
The paper reflects the main tasks that were solved in the course of the work, and the obtained results.
Materials and methods
The effect of geological characteristics on dynamics of the gas oil ratio was investigated using multivariate computational hydrodynamic modeling.
Keywords
associated petroleum gas, dissolved gas, gas oil ratio, hydrodynamic modeling
DOI: 10.24412/2076-6785-2024-4-40-44
Abstract
Corrosion (spontaneous destruction) of metals occurs as a result of the transition of their constituent elements into a state of connection with environmental substances. Corrosion is a serious problem that entails significant economic losses and requires constant attention and research to develop effective methods to combat it. According to Rosneft, in 2023, failures of pumping and compressor equipment due to corrosion occupy the 2nd place after failures associated with the accumulation of mechanical impurities in the extracted products. To reduce the negative impact of the corrosive environment, it is necessary to determine the exact corrosion rates. The article proposes a new method for installing witness samples, which allows taking into account the kinetic features of corrosion on deep-pumping equipment. Using a practical example, the importance of determining the rate of local corrosion is considered and methods for measuring the depths of local damage are proposed.
Materials and methods
Statistical data on failures of deep-pumping equipment, gravimetric method for measuring corrosion rate, double focusing method.
Keywords
complications in oil production, corrosion, corrosion monitoring, local corrosion, tubing, corrosion witness samples, corrosion consumption
DOI: 10.24412/2076-6785-2024-3-50-55
Abstract
The paper presents the results of research on the selection of the optimal composition of an imidazoline-based corrosion inhibitor with ketone or ketoxime for an acidic environment. Studies have been conducted on the effect of temperature on the quality of inhibition. The characteristics of inhibition at different exposure times (up to 720 hours) have been studied. The effect of the fluid flow regime on the quality of inhibition by ketones or ketoximes has been established. It is shown that for any of the cases, changing the mode from laminar to turbulent reduces the degree of protection from 1,5 to 2,2 times.
Materials and methods
GOST 9.506-87, octanone-3, octanone-3-oxime, hydrochloric acid, Steel 3 metal plate.
Keywords
ketone, ketoxime, inhibitor, corrosion, hydrochloric acid
DOI: 10.24412/2076-6785-2024-4-47-51
Abstract
This paper discusses the principles and methods of in-situ section correlation and examples of its application to enhance the quality of petrophysical interpretation. One issue with automatic in-situ correlation is its dependence on the order in which wells are considered. To eliminate this problem, one option is to define the bypass paths of wells based on their proximity according to a Euclidean norm using log curve data. The paper presents an approach to automatic well log correlation using principal cluster analysis, component analysis and dynamic time warping.
Materials and methods
The paper discusses methods for intra-situ correlation of well sections.
Automatic section correlation is based on the use of cluster analysis algorithms, principal component analysis and dynamic transformation of the time scale. Principal component methods and cluster1 analysis are used to organize data from different wells according to geophysical responses, which allows for more efficient cross-section correlation using the dynamic time transformation (DTW) algorithm.
Keywords
well log correlation, k-means method, dynamic time warping, principal component method