bluuebunny/crossref_metadata_2025_split huggingface dataset:
Modeling of Effective Pressure Effect on Deformation Mechanisms of Fractured Reservoirs
Authors: Lukin S. , Oshmarin R , Tugarova M. , Dubinya N. , Chebyshev I. 
Published: October 2015

Abstract
The development of dynamic geomechanical model (including the effect of permeability change caused by stress state alteration) is presented in the paper. The aim of the research is the analysis of conductivity decrease acting on the cumulative production. For the purpose of modeling of reservoir pressure decreasing during field development, the special core analysis method based on the key structural features of the rocks, including the void space has been carried out. Laboratory studies have shown the changes in the morphology and spatial distribution of microcracks after the experiment and the increase in the void space as a whole. In the low permeability samples the decrease in filtration properties is more considerable than in the high permeability ones. It can be explained by the genesis of new microcracks in originally solid crystalline rocks. An application module for combined hydrodynamic and geomechanical modeling was developed based on the introduced mathematical model. The interpreted results of laboratory experiments were integrated in the module. As a result, the existing hydrodynamic models were modified taking into account the alteration of permeability caused by stress field dynamic. The analysis of permeability change altering the cumulative production was carries out.
Record Erd Senomanian wells on Yamal
Authors: Zadvornov Dmitriy , Truba Andrey , Petrakov Yuriy , Sobolev Alexey , Pavlov Valeriy , Dymov Sergey , Grachev Oleg , Sosedkin Dmitriy , Ivashin Maxim , Gaynanov Ilnur , Zhernakov Vladimir , Glebov Evgeniy , Shokarev Ivan , Gulov Artur , Zhludov Alexey 
Published: October 2015

Abstract
The article is based on experience of drilling record Senomanian ERD wells on Yurkharovskoe field from the bank of the Tazovskaya Guba towards offshore.
Core problem happening while drilling such extended wells is wellbore instability happening in mudstone intervals when drilling close to the bedding.
This article is devoted to study of the specific breakout mechanism in mudstone at shallow depth and finding the solution for well trajectory optimization to prevent wellbore instability.
The main problem was solved in the work is optimization of shallow Senomanian wells trajectories via geomechanical modeling coupling with drilling experience which allow to find the solution and solve the instability problems while drilling.
Drilling experinse of Senomanian wells was analized and used for geomechanical model verification and chose the best wells trajectories.
Feature of mudstone collapse while drilling close to bedding at shallow depth was investigated, also termal expansion effect and its inpact on wellbore instability was evaluated.
The result of the work was trajectories optimization and succesfull drilling of Senomanian wells on Yurkharovsko? field. Drilled wells have record horizontal displasement from vertical among all wells on YaNAO.
The aggregate results of engineering calculations and obtained experience of Senomanian wells drilling have perspective opportunities of design and construction of such wells in YaNAO.
Management of Initial Data Uncertainties in 3D Reservoir Simulation
Authors: Sadykov Radik , Mikhaylov Alexey 
Published: October 2015

Abstract
This paper demonstrates the multivariate approach as a tool for the management of initial data uncertainties in 3D reservoir simulation processes. The multivariate approach helps to address several problems, including optimizing the development scenario, determining the well type, and calculating the optimal horizontal well completion system.
The method for determining the optimal development scenarios includes performing multiple forecast runs on simulation models with variations of initial data (such as permeability and water/oil contact) for various development scenarios (including well spacing and development plan). Then, the data are systematized, and a statistical analysis is performed with the calculation of economic indicators. The distributions of technical and economic development parameters are built from the results of these processes. The optimal development scenario is selected directly by selecting the realization with the maximum probability of occurrence from the most economically successful realizations. In other words, a development scenario is considered optimal if it has maximum probability of occurrence in the data set and maximum economic indicators (net present value (NPV) and profitability index (PI)).
The paper uses two case studies to illustrate the multivariate approach for determining the optimal development scenarios by considering the initial data uncertainties.
For gas field A (eastern Caspian, lower Jurassic terrigenous deposits), the task of determining the optimal well type and spacing of the new wells was addressed by using multivariate reservoir simulation. The data uncertainty is attributable to a core test result error in the permeability determination and to a lack of data for the gas/water contact depth in accordance with the well testing and production testing results. A total of 10,000 simulations of the multivariate reservoir and economic model were run to determine the optimal well type and well spacing. In addition, probabilistic values of the development technical and economic indicators P10, P50, and P90 were determined. The results of the calculation enabled the optimal development parameters to be selected and the effect of the initial data uncertainties on the final technical and economic indicators of the field development to be evaluated.
The length of horizontal wells, hydraulic fracture spacing, and optimal well spacing were selected based on the multivariate approach for oilfield B (western Siberian oil and gas province, upper Jurassic). For this purpose, 100,000 iterations of the development scenarios forecast were calculated based on the multivariate simulation model. Based on the analysis of the calculations and economic model, the optimal length of the horizontal section and fracture spacing were selected and justified, enabling the optimal design and completion system for horizontal wells, as well as risk mitigation measures, to be selected.
Risks and Uncertainties Evaluation of Reservoir Models as a Way to Optimal Decisions
Authors: Sazonov Evgenii , Nugaeva Alfiya , Muryzhnikov Anton , Eydinov Dmitry 
Published: October 2015

Abstract
When horizontal wells are being planned, reservoir engineers have specific requirements to the quality of prediction. Knowledge about the reservoir structure and properties, number of reservoir beds and the other parameters in the areas far from the well bores is critical for decision-making. However, all geological modeling tools can only estimate the reservoir properties in the interwell space with some uncertainty. The modern modeling workflows with ensembles of simulation models allow uncertainty and risk analysis with validation of the available data. That helps to investigate different development scenarios and maximize the profit.
In this work, we discuss the workflows for assisted history matching, uncertainty and risk assessment as well as the impact it has on the field development. The paper shares practical experience of application of the model ensembles for history matching and prediction. Multiple solution history matching is obtained with assisted history matching tools. Differential evolution optimization algorithm is used for minimizing the mismatch between the simulation results and the observed data. Tornado diagrams representing the impact of the individual parameters on the objective function value was used for sensitivity analysis and ranging the uncertainty parameters. Eventually, based on the multiple history matching solutions, engineers propose field development plan that is less sensitive to the uncertainty and minimizes the risks.
Multiple solutions are found with evolutionary algorithms, which are based on multiple realizations of simulation models with stochastic distribution of the parameter values. Some practical aspects of application of assisted history matching software are discussed in details. The authors share their experience with the workflows and share some recommendations about the basic steps, such as sensitivity analysis, automatic history matching with optimizers, identifying the key parameters, and ranging the multiple solutions obtained.
The standard company workflows in ANK Bashneft assume that multiple solutions found at the history matching stage are then used for optimization of the new wells or workovers on the existing wells. In this work, we carried out prediction with uncertainty assessment for optimizing operational regimes for injection and production wells, infill drilling scheme, well trajectory optimization, EOR's, oil in place localization and optimization of the lab research program to reduce the model uncertainty. It is clearly demonstrated that the uncertainty quantification helps to make decisions that are more efficient and significantly improve the project economics.
Laboratory and Numerical Study of the Dissolution Process of Salinization Clastic Reservoirs
Authors: Vinogradov I. , Zagorovskiy A. , Bogachev K. , Milyutin S. , Gorbatko E. , Dolgov I. 
Published: October 2015

Abstract
This paper discusses risks of fresh water injection in the terrigenous reservoir of the Verkhnechonsky producing horizon where interstitial space is fully or completely filled with halite (naturally occurring salinization).
Strata of salinized sandstone are believed to be a potential "super" reservoir since when fresh water is injected in the layer it washes out salts and induces a manifold increase in the effective porosity and permeability. Such flooding may accelerate water breakthrough into the producing wells, creating water absorption zones and changing the displacement front. All that reduces sweep efficiency and, with that, oil recovery.
The work has focused on flow experiments with core samples to assess the dynamics of change in the permeability and porosity of the rock and arrived at important conclusions on the characteristics of desalination process. A mathematical model of multi-phase filtration has been built to account for the interaction of water with the reservoir salt which brings about changes in the reservoir properties of the porous medium and rheology of injected water. Numerical experiments have been conducted to study the impact of desalination on viscous displacement of oil.
The paper offers systematic information about the injection experiments with salinized core samples from the Verkhnechonsky formation. It offers a description of the mathematical model of filtration of oil, gas and mineralized water which serves as the basis for hydrodynamic simulation at different levels (from core models to a full-scale model of the Verkhnechonsky horizon).
The results obtained give insight into key factors that accompany dissolution of reservoir salt in the injected fresh water, as well as their effect on the efficiency of water-flooding of salinized reservoirs.
The study will be of interest for specialists at oil companies which have in their portfolio oil fields with subsalt and inter-salt oil deposits.
Modelling Non-Equilibrium Phase Behavior of Hydrocarbon Mixtures
Authors: Lobanova O. A. , Indrupsky I. M. 
Published: October 2015

Abstract
A physically-consistent method is suggested for calculation of coexistent hydrocarbon phases' compositions in flow simulations with non-equilibrium phase transitions. The method preserves standard flow terms' formulation and can be incorporated in existing commercial simulators without principal modifications to flow simulation algorithms.
Through the analysis of laboratory experiments data and computational studies, we show that the necessity for non-equilibrium phase behavior model depends on simulation scale. We introduce an upscaling algorithm to estimate parameters of a non-equilibrium coarse grid model.
An algorithm is proposed to calculate non-equilibrium phase compositions with desired level of non-equilibrium behavior and model different speeds of relaxation of fluids' compositions to their equilibrium states. Relaxation dynamics is determined by pressure changing rate as well as initial phase compositions and pressure. These effects are essential for consistent history matching of a flow simulation model of an oil or gas-condensate reservoir with minimal number of matching parameters.
Examples of using the method to simulate non-equilibrium phase behavior of real oil and gas-condensate mixtures are presented.
3D Geomechanical Modeling of Oil Field on the Basis of a Model of the Mechanical Properties for the Task of Wells Construction
Authors: Garagash I. A. , Dubovskaya A. V. , Bayuk I. O. , Tikhotskiy S. A. , Glubokovskikh S. , Korneva D. A. , Berezina I. A. 
Published: October 2015

Abstract
The paper is dedicated to the method of an oilfield geomechanical model construction based on common exploration dataset. Geomechanical modeling can be used to reduce well drilling risks in complicated geological conditions.
Following steps of model construction are described: (a) a construction of mechanical rock properties model; (b) a way to determine rheology, model boundary conditions, external loads and calculate stress state; (c) an evaluation of pore pressures.
Moreover possible methods of improving the model quality are discussed.
It is shown that taking into account the dependence of internal friction angle upon accumulated inelastic strain allows us to obtain more realistic stress-strain curve.
An influence of nonlinear salt creep on the orientation of the principal stress axes is investigated and discussed. As well it is discussed which laboratory core tests should be done to improve the quality of the model.
Real-Time Production Optimization of an Intelligent Well Offshore, Caspian Sea
Authors: Shestov Sergey , Golenkin Mikhail , Senkov Aleksandr , Blekhman Vadim , Gottumukkala Varma , Bulygin Igor 
Published: October 2015

Abstract
Recent advances in development of hardware for reservoir monitoring have caused rapid changes in production logging and testing techniques for instrumented wells. On-demand actuations of downhole valves and data acquisition from the downhole gauges remain available well into the useful well life due to improved reliability of the downhole equipment. A specific layout of the gauges could be tailored to support various types of production logging, and pressure transient and production tests1,2. Instead of the often costly one-off surveys required for a the non-instrumented wells, both data gathering and interpretation become part of a continuous surveillance cycle for an instrumented, "intelligent" well. The resulting exhaustively sampled data sets from instrumented wells are typically very large and require substantial cleansing and cross-calibration with a range of physical models as well as empirical trends to extract valuable information encoded in the data3. Most of these workflows also support decision making in real time.
The paper outlines practical ways of combining known well-testing principals with the modern downhole completion instrumentation to estimate production rate, productivity index, and reservoir pressure using surveillance workflows for a multi-zone intelligent completion in the Korchagina field, Russia. Data from permanent downhole pressure gauges supports a number of real-time workflows including those for zonal rate and productivity allocation. Sequential valve cycling can be interpreted as a multi rate inflow test and, when combined with initial well test data, can calibrate the rate allocation procedure. Meeting production goals for each of the zones requires a real-time optimization technique for setting the valve positions. The procedure was implemented in a form of automated surveillance software for pressure, rate, and productivity allocation and does not require shut-ins to obtain well test data.
Proppant Flow Back Control for Fracturing Low Temperature Formations of Russia Methodology and Case Studies
Authors: Letichevskiy Alexander , Parfenov Alexey , Belyakova Lyudmila , Konchenko Andrey , Borisenko Alexey , Parkhonyuk Sergey , Olennikova Olesya , Klyubin Artem 
Published: October 2015

Abstract
Formations with a bottomhole static temperature below 70 degC are very common for quite a number of Russian oil provences such as Komi, Samara Area, Orenburg, Tatarstan Bashkiria, and Eastern Siberia. Many of these formations are now being developed with proppant fracturing which incorporates a lot of flow back issues due to the various reasons including high viscosity oil, aggressive TSO designs and cycle loads on a proppant pack due to ESP change regime. There are a number of solutions to prevent proppant flow back and the most common one is usage of resin- coated proppants. At temperatures below 70degC RCP needs chemical activation in order to achieve a solid proppant pack consolidation. Depending on temperature range and coating structure various types of activators can be used. Traditionally commercial activators were used at very high concentrations that may compromise proppant pack conductivity and performance fracturing fluid. Alternative techniques are based on using fiber technologies and unconventionally shaped proppants.
The majority of flowback control techniques have been tested in Volga-Urals region of Russia, Orenburg, Samara and Bashkiria areas. Novel additives that accelerate curing, RCP was successfully implemented and pumped during hydraulic fracturing on the most oil fields of Samara area. Flow back problems were observed only at extremely low temperature reservoir (&lt;30 degrees Celcius) with high- viscous (∼100+ cP) oil. Paper uncovers the details of activation process with detailed laboratory investigation for several RCPs and activators, proposes decision matrix for low temperature flow back control techniques, its applicability and design.
Implementation of New Multi Module Configurations in Wireline Logging Suits. Case Studies
Authors: Yakovlev M. , Feofilov D. , Zakirov A. , Usov I. , Sharipov R. , Dontsov E. 
Published: October 2015

Abstract
The report describes a logging technique applied by CJSC PGO Tyumenpromgeofizika on JSC NK Rosneft (OJSC Samotlorneftegaz, OJSC Varyeganneftegaz, LLC RN-Uvatneftegaz) fields for standard logging in uncased, directional and horizontal production wells.
The Information Support of Fluid Sample'S Lifecycle From the Planning Through to Analysis of the Laboratory Tests Results
Authors: Efimov D. V. , Shlychkov K. E. , Minikeeva L. R. 
Published: October 2015

Abstract
The paper presents an experience of developing and implementing information and analytical system (IAS) which provides informational, functional and methodical support for the fluid sample lifecycle.
The comprehensive approach is demonstrated to solve the problem set. The full process from scope or domain analysis and creation of main stages of PVT information flow to design of the project system information model and its technical implementation is described. To ensure the complexity or comprehensiveness principle the term ‘fluid sample lifecycle’ is introduced meaning transformation of PVT information when proceding from sample planning to the actual sampling and further to fluid sample analysis, storage and utilization of the analysis results.
The analysis of the domain or study area related to PVT data composition and usage identified the corresponding production processes and the main stages thereof, the information composed at each stage was also characterized. Based on this analysis main requirements for informational, functional and analytical components of IAS were defined. Moreover, these requirements may differ at each stage of PVT information flow.
On the basis of the analysis results the information model of IAS was created which provides storage of both the initial information on the sample and interpretation results of its analysis.
Technical realization of IAS implied the development of the two related but separate parts: the information core which reflects the information model and is aimed at data storage, and the interface shell which provides both the standard database functionality and tools to process and analyze the information.
Also in the framework of this work problems of the required accompanying and support documentation were addressed.
Development of Remote Gas Condensate Fields: Challenges and Solutions
Authors: Nikonov A. , Pyatov I. , Kruptsev A. , Zhukov S. , Egorova E. , Lievois J. , Muravyev A. 
Published: October 2015

Abstract
There are many problems associated with the development of remote gas condensate fields that can be alleviated by seamlessly integrating key engineering aspects such as recovery plan, production optimization, processing, waste management, and logistics.
Production optimization requires monitoring of production oil, water, and gas rates along with reservoir conditions. This can prevent economic losses by providing early detection of reservoir problems like condensate banking. Multiphase flowmeters provide compact, cost effective well testing plus real time data for improved well performance analysis. Separation, feed preparation and processing in the vicinity of production sites is performed using compact modular equipment. Catalytic desulphurization ensures high quality treatment. New atmospheric pressure catalytic treatment technologies used for gas condensate and various quality oils enable production of diesel fuel (including Arctic) and high-octane gasoline. Location of fuels and lubricants (POL) production near oil and gas production sites can solve problems associated with delivering those supplies to Northern areas, ensure efficient sales of well production, enable year-round operation of special road machinery, and reduce operating costs.
A closed loop system integrating production optimization, feed preparation technologies, modular processing systems, electric power generation using gas generators, associated natural gas conversion into synthetic gas and container-based wastewater treatment plants produces a powerful synergetic effect and offers opportunities to develop hard-to-reach areas. Integrated modular production systems will help unlock Siberia’s vast natural resources both hydrocarbon and non-hydrocarbon. The potential for local energy supply may be a key economic consideration for further production of Siberia’s mineral resources.