bluuebunny/crossref_metadata_2025 huggingface dataset:
Gazprom Neft Experience of Bazhenov Suite Development
Authors: Vashkevich Alexey , Strizhnev Kirill , Zhukov Vladislav
Published: September 2014

An approach in Bazhenov formation exploration applied by Gazprom Neft is presented. Projects implemented in the company are pointed on making of a complex system that includes regional studies, geological exploration and pilot operations, learning and adaptation of the best world practices and creating own tools and techniques for research and development of Bazhenov formation. Major mining and service companies, science-research institutes are participating in these projects.

By this time multifunctional group of specialists deduced criterions of oil and gas extraction availability, and the most attractive zones ("sweet spots") of Bazhenov formation spreading were selected. On the base of deduced criterions presumptions of Bazhenov formation productivity were gathered. Examining of these presumptions and more detailed exploration of the researched object and approbation of techniques and technologies of oil extraction are being made by geological exploratory and pilot projects in the current licensed spots of the company. The first results of these works showed availability of development of Bazhenov formation in Western Siberia.
Prospects of Shale Oil Bazhenov Formation in the South-East of Western Siberia
Authors: Goncharov I. V. , Samoilenko V. V. , Oblasov N. V.
Published: September 2014

South-east of Western Siberia (Tomsk Region) faces good prospects for developing shale oils from Bazhenov formation. Ample preconditions are available there: high content of organic matter of excellent oil-generating quality in Bazhenov formation rocks and main oil formation stage of primary rocks. However, drilling success appreciably depends on the correct choice of the well spud-in place.

Regional geochemical investigations of Bazhenov formation and of Bazhenov genetic type of oils may considerably confine the area of search by choosing the most promising areas for detecting shale oil deposit.

Recent investigations permitted to identify a regional pattern of changes in Bazhenov formation rocks catagenesis and to grade the prospective regional oil-bearing capacity associated with hydrocarbon generation by Bazhenov formation rocks. Identification of regularities in expansion of Bazhenov - type oils as well as comparison between the maturity of oils and the maturity of organic matter of Bazhenov formation rocks permitted to mark out areas that are promising for the formation of both oil deposit in traditional oil reservoirs and of shale oil deposit.
Using NMR Relaxometer in the Study of Unconventional Rocks Characteristics
Authors: Vavilin V. , Galiyev T. , Kunakasov A. , Sorokina E.
Published: September 2014

NUCLEAR MAGNETIC RESONANCE (NMR), NMR RELAXOMETER, STRUCTURE OF VOID SPACE, "FRITILLARY", "WEATHERING CRUST", "BAZHENITE" (OIL SHALES), BI-MODAL NMR DISTRIBUTION, ROUTINE CAPILLARY METHODS

This paper presents the results of NMR studies of structure of void space of rocks from unconventional reservoirs.

Objects of the study - "fritillary", "weathering crust", "bazhenite". These rocks are difficult for studying by conventional methods due to their high heterogeneity, low porosity and permeability, presence of large amounts of clays. Therefore we have used NMR relaxometer to study the structure of void space of such rocks.

We have studied more than 200 samples of the three rock types, made more than 500 NMR measurements on 100% saturated and dry samples.

The nuclear magnetic resonance (NMR), accurate and non-destructive technique, was selected for these rocks,, because the standard methods for capillarity of rocks investigation (capillary pressure by porous plate and by centrifugation) do not reveal the characteristic features of the void space structure which are inherent for these rocks.

These standard techniques doesn't allow to determine the pore sizes and pore channels of less than 0.1 microns, and by these methods it is impossible to study the so called "clay bound water" as a component in the fluids distribution in the rock.

Same samples, were also undergone through routine core analysis measurements (permeability and porosity),, as well as detailed lithological studies using a scanning electron microscope and gas chro-matograph.
Examples of Mini-Frac Test Data Interpretation in Low-Permeability Reservoir
Authors: Makhota N. , Davletbaev A. , Federov A. , Asmandiyarov R. , Afanasiev I. , Sergeychev A. , Yamalov I.
Published: September 2014

When dealing with ultra low-permeability reservoirs, one comes across a certain problem of choosing low cost way of getting reservoir pressure data. Classical well test implies long-lasting shut down of production wells (up to several months) due to low permeability and presence of extended hydraulic fractures. The paper contains examples of surveys carried out using hydrodynamic logging. These tests show significant restrictions of the method applied in low permeability resevoirs.

Well pressure based on minifrac test data was evaluated here for ultra low permeability reservoirs. Then the data was then compared with the results of average pressure at hydrodynamic logging. Fracture closure pressure data was used to enrich correlation dependencies for fracture closure pressure (spontaneous growth of fracture) in injection wells using well pressure fall-off curve interpretation methods during minifrac test. Each minifrac test in horizontal wells with multi-stage fracturing was analysed, the results of injection efficiency ratio were gained that are in agreement with production profile according to PLT and allow to test the most productive well influx intervals.
Competencies Transfer for Offshore Russian Operators
Authors: Lavrov Vladimir V. , Fedorov Konstantin M. , McMorren Paul D. , Nalimov Gennady P.
Published: September 2014

Breakthrough in techniques and technologies in oil and gas recovery onshore and offshore changed the reqirements to the personell of operators all over the world. For Russia Petroleum industry the main professional deficit is desplyed in offshore field development. The problem is complex because Arctic challenge incorporates morden offshore technologies and undissolved objectives of their adaptation to severe north conditions.

Two ways of offshore competencies transfer from leading centers to Russian personell market are considered. Future perspectives of Russian shelf development defines the way of formation of own Russian competencies through involvement of professional courses from foreign Universitites and internships in production and service companies. The experience of integration of academical knowledge and professional practice in training and engineering clusters is outlined.

The utiliuzation of State Universities and private initiatives are compaired. The experience of OIL-TEAM Company and its Academy in competencies tranfer are considered. Key aspects of successful development of educational project are analized.
Advantages of Fluvial Reservoir Object Modeling
Authors: Shishmanidi I. , Martynov M. , Kozlov A.
Published: September 2014

The article presents object-based method for creating three-dimensional geological model of continental deposits (Tyumen formation case study). The input dataset of geological and geophysical information to support spatial, morphological and compositional characteristics of the facilities and principles of data implementation in the model are determined. The methodology allows to integrate in a model concept of the sedimentation and create geologically validated reservoir bodies. The results are applicable for reservoir connectivity analysis, well placement, waterflooding optimization.
Estimability of Heavy Oil Viscosity by Nuclear Magnetic Resonances Researches
Authors: Musin Kamil , Bobb Irina , Abdullin Timur , Khisamov Rais , Skirda Vladimir , Gizatullin Bulat , Zaripov Timur
Published: September 2014

This paper presents the results of laboratory and nuclear magnetic resonances researches of seventy-seven crude oil samples from the Devonian, Carboniferous and Permian formations of Tatarstan oil fields with a wide range of viscosity varying from several cps to 60,000 cps.

The results can be used to estimate the viscosity of the oil, including in situ viscosity. It has been found that the NMR relaxation characteristics of the tested samples presented in the form of T2 time distribution spectra confirm that crude oil is multicomponent. Numerical characteristics resulting from the analysis of the spectrum of spin-spin relaxation time T2 have been determined, which show good correlation with the viscosity of the hydrocarbon fluid. The paper presents the obtained experimental correlations between the rheological properties and NMR characteristics for oil samples studied.
Evaluation of Thin Laminated Reservoirs - Hidden Problems
Authors: Oshnyakov I. , Khabarov A. , Malshakov A.
Published: September 2014

The depletion of the majority of mature fields with the best reservoir properties and the easiest extracted reserves determines the necessity of involvement in the elaboration structurally complex reservoirs of different kind.

Among them a special place occupy laminated sands, which can contain and produce oil and gas. However, ther is a number of problems associated with determination of their reservoir properties, reserves volume and effective development.

In this context PK formation of Russkoye field in Western Siberia is the classical example of such kind of objects (Pic. 1.). The main problem is that the shale microlayers are not resolvable on the logging curves, as their thickness is much less than the resolution of the main well logs. The logging methods characterize integral rock properties (sandstone and shale alternation). The usage of classical approach does not allow determine the real properties of sandstones, and net thickness estimated by conventional log evaluation is not real, as it contains impermeable shale microlayers.

So, the petrophysical model of homogeneous reservoir, made previously, does not correspond to the results of hydrodynamic modeling. There was no success in its adaptation without significant increase of permeability and oil and gas saturation.
Geology and Petroleum Potential of the Gulf of Mexico, Cuba
Authors: Ananev V. V. , Verzhbitskiy V. E. , Obukhov A. N. , Borisov D. V. , Nortsev G. V.
Published: September 2014

Oil-and-gas potential of Cuba is ascertained by discoveries among which there are the most large-scale deposits, such as Boca de Jaruco and Varadero fields of heavy oils. Currently the petroleum and petroleum products needs of the island state are satisfied by own sources by less than a half. Prospects of the hydrocarbon resource base development are connected with the adjacent water area of the Gulf of Mexico where foreign companies have been granted license blocks for geological study and further development since 2001. Two Russian companies – JSC Gazprom Neft and OJSC Zarubezhneft among others took part in the development of the Cuban part of the Gulf of Mexico. Since 2004 5 oil wells have been drilled by various companies in deep water of the exclusive economic zone of Cuba. Commercial oil-and-gas bearing prospects have been established in neither of them for both geological and technological reasons. However, only a small part of the water area has been covered by drilling and the productivity of the drill core has been tested at the depth of Cretaceous sediments only. In our opinion, oil-and-gas bearing prospects of the exclusive economic zone of the Republic of Cuba in the Gulf of Mexico remain undervalued and the mentioned water area needs additional geological exploration. Planning of exploration work in this poorly explored region shall be carried out systematically and it shall be based on the results of the regional scientific research.
Oil Viscosity Impact on Invasion Zone Structure and Resistivity Measurements
Authors: Karpov Igor , Makarov Alexander , Eltsov Igor
Published: September 2014

The invasion zone structure and its radial depth depend on formation properties and fluid parameters. Previous research described a methodology for invasion zone reconstruction established from logging data and mud filtration simulation. Fluid mobility in porous media is affected by viscosity; therefore, it is important to understand the effects of oil viscosity on mud filtration. The study presents how oil viscosity and its dependence on formation conditions affect formation resistivity measurements.

Buckley-Leverett equations are used to simulate the invasion process established from drilling and formation parameters pertinent to true reservoir conditions. At the end of the invasion process, the resistivity radial profile (from borehole wall to undisturbed formation) strongly depends on oil viscosity: for example, increasing oil viscosity from 1 cP to 25 cP increases the resistivity of the invaded zone by three times. Resistivity is computed via the Archie equation by taking into account water/oil saturation and salinity. The resistivity profiles are used as input data for forward modeling of the induction logging tool (IL). High-frequency probes (2 MHz) are very sensitive to variations in oil viscosity. The responses of short-spaced (23 inches) probes vary from each other by approximately 21%, with signals of long-spaced (35 inches) IL probes varying by approximately 7%.

Detailed understanding of formation oil properties reduces the ambiguity of resistivity models in the inversion of electromagnetic data. Particularly, knowledge of oil viscosity influence on a resistivity profile is useful for improving the quality of formation evaluations using resistivity logs.
Practical Approach in Planning Well Testing in South Tyumen Region for Improving Data Quality
Authors: Kulyatin O. Yu. , Kulik A. P. , Sosnovskikh A. I.
Published: September 2014

Present article describes workflow and experience acquired during well testing at exploration wells in Uvat district of Tyumen region. Due to significant remoteness of well site activity from established infrastructure, practical approach with compact and effective technological solutions was developed, and thus, can be successfully employed on wide range of other wells and fields with similar remoteness and conditions.

Optimized workflow based on usage of well test string with jet pump, reverse check-in valve and packer during well clean-up and testing sequence is illustrated. Usage of deployed string ensures effective execution of clean-up works on mid-rate to no-natural-flow zones and provides acquisition of quality data on bottomhole pressure through flowing to build-up. Also, this technical solution allows performing full cycle of hydrodynamics well testing operations on target zone in relatively short period, in order of five to seven days for common geology and well conditions. Simultaneous usage of packer and reverse check-in valve drastically reduces wellbore storage effect and allows obtaining detailed pressure dynamics data, characterizing formation properties within corresponding period and radius of investigation.

Through execution of well testing program on more than thirty target zones in frame of exploration drilling campaign, quality assurance, quality control methodology was developed to ensure quality and completeness of acquired data. In addition, process on preliminary data analysis was implemented to discover any potential flaws in data and materials. Inconsistence, lack of data, hidden technological defects shall be identified and activity to be repeated for good data acquisition prior accomplishing of well site operations on target zone. Thus, quality of final well test data set is drastically improved.
Coupled Geomechanical and Fluid Flow Simulation of the Oil Field Evolution Induced by Reservoir Production
Authors: Garagash I. A. , Dubovskaya A. V. , Korneva D. A. , Ghasemi M. F.
Published: September 2014

This paper presents a coupled geomechancal and fluid flow simulation for a hydrocarbon reservoir in exploitation process. Two simulators have been used: 1. Geomechanical simulation software FLAC3D which uses Finite Difference Method and 2. tNavigator which is a Finite Element solver engin for fluid flow simulation in porous media. The parameters connecting fluid flow and geomechanical simulators mainly are porosity and reservoir pressure.

Pore pressure changes in depletion process of reservoir cause changes in stress and strain tensor in hydrocarbon bearing and adjacent formations. Changes in spherical stress tensor in its turn cause a reduction in porosity, which affects the results of the fluid flow simulation.

To verify the geomechanical computations, calculated stress distribution has been compared with analytical and empirical solutions. With coupled reservoir simulation we can predict flow rate for each well, recoverable reserves and also other required parametrs in reservoir life and production process, more accurate and reliable. We will be able to evaluate tensors of stress and strain for hydrocarbon bearing formations and adjacent layers. These stress data can be used in wellbore stability analysis in whole reservoir life.
Reservoir Monitoring of Hydrocarbon-Water Flood Front by Gravimetry Integrated within Reservoir Simulation
Authors: Dyatlov Gleb , Lyngra Stig , Marsala Alberto F. , Loermans A. M. , Georgi Daniel T. , Vasilevskiy Alexandr , Dashevsky Yuliy , Edwards Carl M.
Published: September 2014

Gravimetry is a physical method with a large depth of investigation. Traditional applications include surface gravity observations for mining and oil exploration and borehole gravity logging for investigating formation bulk density.

A new application of gravimetry is large-scale reservoir saturation monitoring. Replacement of oil or gas by water leads to density changes in large volumes of the reservoir, which causes changes of the gravity field down hole as well as on the surface. Since borehole gravity sensors are closer to the reservoir than for surface acquired gravity data, borehole gravity data has better spatial resolution and are less affected by near surface changes.

This paper focuses on the problems of inversion of time-lapse gravity data for complex multilayered reservoirs and estimation of the accuracy of the reconstructed oil-water flood front. The traditional bitmap approach (dividing the reservoir into blocks) requires a huge number of parameters and leads to the well-known inversion ambiguity. This ambiguity can be reduced by introducing a priori information.

The basic idea of the presented approach is to obtain this a priori information by biasing the inversion with output from a history matched reservoir simulation data set. In this case, reservoir simulation saturation data from an onshore giant Middle Eastern oil field was used as input. By processing the simulation saturation data, it was possible to understand the behavior of the water saturation and oil-water flood front in the different layers of the reservoir. Using this knowledge, a 3D model of density changes was introduced. This model formed the basis of the optimization inversion algorithm used to fine-tune the actual location of the oil-water flood front on the basis of gravity data.

Numerical examples demonstrate how inversion and accuracy estimates work for data obtained from a realistic reservoir simulation. The proposed inversion technique will depict any differences from the history matched reservoir simulation saturation output and the gravity data; thus, the gravity data will allow enhanced precision of the reservoir simulation history match.
New Well-Test Interpretation Method for Carbonates Reservoirs With Rare Long Fractures for Field Development Optimization
Authors: Morozovskiy Nikita , Kremenetskiy Mikhail
Published: September 2014

This article is devoted to carrying out and interpreting well tests that reveal carbonate reservoirs with a developed system of conducting macrofractures. Relevance of the issue is due to not only the increase the number of such reservoirs in the structure of hydrocarbon reserves, but generally by domestic companies’ low experience in production from such reservoirs.

It was found out that in the presence of rare and extended natural fractures the traditional model of «dual porosity» is ineffective.

The authors studied more complex numerical model, which assumes the existence of a few fractures of different length in the formation as well as fracture systems that are uniformly distributed in reservoir. The cases where the well was at different distances from the fractures or penetrate fracture system were also considered.

The numerical model parameters were adjusted to the results of core analysis, geophysical studies, logging and the history of the wells production history.

The simulation results revealed that the hypothesis of fractured block structure of carbonate reservoirs correlates well with the results of well tests. The technique of determining the parameters of the fracture system according to the well test is validated. The distance to the nearest fractures and the average size of blocks are determined. It is shown that by the well tests in several wells the direction of extended natural fractures can be determined. This gives an indication of the spatial orientation of fractures and their areal distribution.

The obtained results allow to approach the development of new carbonate deposits more rationally, to plan future wells spacing reasonably, to predict well rates and production profile, to consider the consequences of the well interference by the main fractures.
Multi-Criteria Analysis and Optimization of Waterflood Systems in Brownfields
Authors: Voznyuk A. S. , Rykov A. I. , Kotov V. S.
Published: September 2014

This paper describes a methodology for waterflooding pattern optimization based on multi-criteria analysis of the interaction between producers and injectors. This method takes advantage on the use of streamlines which are generated from the post-processing of finite difference simulation results to define the flow paths between injectors and producers and characterize flow allocation between interacting wells. This information is then combined with well production/injection data (oil / water rates, pressures etc.) to calculate parameters like compensation ratio and injection efficiency for each well. Having all this information, a set of cross-plots is used to rank the producers and injectors by their sweep / drainage efficiency.

The results of such analysis allows the planning of workovers, optimization and allocation of the volumes of injected water and ultimately enables a comparative assessment of the efficiency of each individual workover event in terms of incremental oil production, water-cut reduction and decrease in non-effective water injection.

One of the advantages of this method is the use of already available results from finite difference simulation. This fact dramatically increases the time available for the waterflood optimization process and significantly widen the range of scenarios where streamlines technologies can be applied. Moreover, this approach does not require significant or time-consuming computational efforts, which make it a very convenient decision-making tool for field operations planning.
Field Study of Temperature Simulators Application for Quantitative Interpretation of Transient Thermal Logging in a Multipay Well
Authors: Valiullin R. , Ramazanov A. , Sadretdinov A. , Sharafutdinov R. , Shako V. , Sidorova M. , Kryuchatov D.
Published: September 2014

Temperature wellbore studies are widely applied for well testing and logging at the stages of exploration and development. However, in nowadays practice the interpretation is still done mainly qualitatively. In last few years different approaches to joint interpretation of temperature along with pressure and flow rates are discussed more and more widely. In particular, there is a special interest in determination of flow profile and individual properties of near-wellbore zone of perforated wells in multi-layer reservoirs from analysis of transient temperature and pressure during different transitional regimes.

In this work an application of mathematical modeling to quantitative interpretation of field temperature data from multi-layer wells is discussed.

For assessing flow rates and hydrodynamic parameter of individual layers of a multi-layer well, different approaches to inverse problem solution are analyzed. It is pointed out that for reaching higher reliability it is necessary to use for interpretation all available field data, including unsteady temperature logging data. Reasons of disagreement between field and simulation data are discussed.

The analysis of uncertainties arising in interpreting data from deviated wells is presented that indicates necessity to apply additional methods of analysis. It is shown that making use of supplementary simulations allows reaching better agreement between field and simulation data.

Therefore, the complex approach to interpretation of thermal logging data comprising application of sophisticated numerical temperature simulators to interpretation of the full available field data set of temperature logs and fixed-depth measurements accompanied by uncertainty analysis allows, on the one hand, to increase reliability of qualitative interpretation results and, on the other, to provide quantitative analysis of flow profiles and hydrodynamic properties of multi-layer well.
Calculating Prediction Uncertainty using Posterior Ensembles Generated from Proxy Models
Authors: Fillacier S. , Fincham A. E. , Hammersley R. P. , Heritage J. R. , Kolbikova I. , Peacock G. , Soloviev V. Y.
Published: September 2014

Most hydrocarbon fields have been operating for long enough to have significant production history. To quantify uncertainty in future yields it is essential to have a workflow that includes reservoir uncertainties in a way that respects the history. This starts with a simulation model, or more generally a forward model, that has been parameterised by uncertain input parameters with prior distributions. Proxy models can then be created to approximate chosen simulation outputs for all valid parameter combinations, based on a relatively small number of simulator runs. Each combination can be appropriately "weighted", using Bayesian methods, on the basis of the production history. This generates a probability distribution over the range of all possible history matches. Using the proxy models and Markov Chain Monte Carlo techniques it is possible to sample correctly from this probability.

Prediction uncertainty can now be calculated using two related and complementary mechanisms. The first is to take a moderately small sample (say 100) of parameter combinations to create a posterior ensemble of simulation runs. The prediction uncertainty can then be calculated directly from the ensemble of runs. The second is to create new proxy models which approximate the prediction responses of interest. The complementary benefits of the two approaches are discussed in this paper.
New Approach to PVT Correlation Selection
Authors: Khabibullin R. , Khasanov M. , Brusilovsky A. , Odegov A. , Serebryakova D. , Krasnov V.
Published: September 2014

This paper attempts to provide engineer with GOR PVT correlation selection rules. Rules based on comparison of standard PVT correlations with calculations based on Equation of State, which believed to have wider applicability range and be more general from physical point of view.

To make that comparison synthetic oils data bank where generated. Ranges for synthetic oils properties were chosen to cover all the real oils of interest (mainly from Western Siberia). All synthetic oils where analyzed using Peng Robinson equation of state with shift parameter and widely spread PVT correlations.

Results provided as GOR PVT correlation Applicably Maps and New Procedure calculation GOR by selected PVT correlation. Result was checked during PVT study of few Western Siberia oil fields.
Development and Deployment of Technology Complex of Use of Associated Gas for Increase in Oil Recovery
Authors: Kokorev V. , Darishchev V. , Akhmadeyshin I. , Bugaev K. , Shchekoldin K.
Published: September 2014

In article the main development stages and implementations of the equipment for associated petroleum gas use for the purpose of oil recovery increase are stated. The main difference of the developed equipment is the compressorless technology of pumping gas in the form of finely divided water gas mix.
Identification of Behind-Casing Flowing Reservoir Intervals by the Integrated High-Precision Temperature and Spectral Noise Logging Techniques
Authors: Lutfullin A. A. , Abdrahimov A. R. , Shigapov I. N. , Aslanyan I. Yu. , Aslanyan A. M. , Kuzyutin R. K.
Published: September 2014

Hydrocarbon production from low permeability reservoirs has been steadily growing in the Russian Federation lately. The reservoir sweep efficiency and behind casing integrity has become even more important than it was in conventional formations – mainly because the target oil/gas pays has experienced tough competition from higher permeable water pays. In high permeability formations one can normally track production profile with a conventional production logging tool based on a mechanical spinner and based on that schedule the treatment to arrest water cut growth. In low permeability formation most communication happen behind the casing and those flowing inside the borehole are usually too slow to be captured by the mechanical spinner.

This paper shows how high-sensitivity broadband Spectral Noise Logging [1–4], High-Precision Temperature Logging [1] and flow modeling in combination with conventional production logging can produce valuable information on gas, oil and water flow profile and behind casing communication (whether a cement rim channeling or a reservoir fracture flow). The technology is illustrated with three case studies from the East-Tarkosalinskoye field of the Yamalo-Nenets Autonomous Region (North Russia). One case was a vertical well and the two others are horizontal wells with multi-zone hydraulic fracturing. An integrated analysis of acquired data identified the sources of water production and also revealed the non-producing reservoir zones. Special attention was paid to the analysis of annular and behind-casing cross-flows.

One horizontal well was worked over with a cementing job around the zone identified as the water source from the HPT-SNL survey and resulted in total shut-down of water production with no impact on oil production.
Building of a Multiple Layer Oil and Gas Condensate Field Integrated Simulation Model
Authors: Kuzevanov M. A. , Buchinskiy S. V. , Glumov D. N. , Reitblat E. A.
Published: September 2014

Specific of gas field development suggests a constant level of gas production in order to provide stable loading of gas field processing and transport facilities. At this point, when production of major development objects commences to fall, start of minor objects production is supposed to occur. Having united surface facility and separate reservoir simulation of segregated layers with joint well stock a question of accuracy in measurement of hydrocarbon production is arisen. In addition, at the entry of production of minor objects with distinctive reservoir pressure a problem of appropriate distribution of wellhead and downstream pressures can be revealed.

In this paper mechanism of building of a multiple layer oil and gas condensate field integrated simulation model (ISM) is described. Construction of integrated model will allow resolving the problems outlined above. Besides, running of field development simulation cases with different order and tempo of production will be significantly simplified.

Separate compositional models made for each development object have been selected for integration in the ISM. However, consolidation of these models is complicated by the issue of demanding a lot of resources for storage and computation time. Therefore, a transition from compositional to black oil models has been performed in order to obtain production data. Detailed gas composition required for integration with a gas processing system can be gained by a delamping procedure.

As a result of building integrated simulation model a flexible tool of effective management of field development has been obtained that makes it possible to run simulations for both major and minor objects simultaneously and taking into account the field infrastructure (gathering and compressor facility); to assess the possibility of joint production of separate layers and consider the impact of gathering system on hydrocarbon production as well. When comparing the simulation time in different types of models, without significant loss of simulation quality, the average acceleration is about twenty times. This allows obtaining results much faster and further improving it.
The Solution of Problems of a Nonequilibrium Nonlinear Filtration on Commercial Simulators
Authors: Cheremisin A. N. , Cheremisin N. A. , Kostuchenko S. V. , Toropetsky K. V. , Ryazantsev A. E.
Published: September 2014

Summary

Results of computing experiments have shown that influence of effects of a nonequilibrium filtration (nonlinearity of the law of Darcy for liquids, existence of a limiting gradient of shift, creeping deformation of the steam environment) on results of hydrodynamic modelling and design of systems of development of oil fields and gas considerably. For the accounting of these factors, authors have developed methodical receptions, algorithms and the applied software for the solution of actual problems of a nonequilibrium multiphase filtration with use of commercial simulators. In the report, examples of the solution of such tasks for models of real fields are given and necessary recommendations are made.
Condensate Production Optimization Using MEPO Software Combined With Eclipse-Network
Authors: Skvortsov D. O. , Glumov D. N.
Published: September 2014

The article describes modern approaches to modeling gas condensate field development focused on increased condensate production while maintaining desined gas recoveries.
Practice of Complex Architecture Well Construction at the Oil Fields of OAO LUKOIL in Western Siberia
Authors: Bakirov D. L. , Fattakhov M. M. , Bondarenko L. S.
Published: September 2014

The paper presents the designs of complex architecture wells applied in the oil fields of OAO LUKOIL in Western Siberia and presents some experience in construction of these wells.
Best Practice of Horizontal Well Construction Operations for the Challenging, High-Pressure Achimov Formation – Urengoyskoe Field
Authors: Dobrokhleb P. , Ablaev A. , Chetverikov D. , Zavarigin S. , Inyushina A. , Petrakov Y. , Sobolev A. , Zadvornov D. , Tarasov O. , Milushkin A. , Milenkiy A. , Grigoryev M. , Sidorov D.
Published: September 2014

Achimov deposits extend over 12,000 square kilometers around the city of Novy Urengoy. These deposits are characterized by high reservoir pressures, and a narrow range of drilling fluid densities that creates complicated conditions for drilling and completion of wells. Due to the high accident rate of drilling horizontal wells only S-shape wells were drilled for this formation.

The first successful horizontal production well was drilled in 2013 in cooperation Arcticgaz, ERIELL, Schlumberger.

The first well to drill a horizontal wellbore on Achimov formation, has been planned to open Ach3,4 and Ach5 layers of Achimov formation.

In close cooperation with project operator - Arcticgaz company, engineering group of Schlumberger drilling contractor and drilling contractor developed and successfully implemented comprehensive solutions for drilling and completion of horizontal wells Achim. One of the key factors of success was the use of drilling muds Megadril-D with constant control of equivalent circulating density. Application of rotary steareable system with optimally balanced PDC bits, allowed to drill horizontal wells through Achimov deposits in record time.

An additional factor for drilling risks reduction was implementation of geomechanic model, as in the preparation of the preliminary model and real-time control for wellbore stability with the latest technology logging measurements (LWD) – acoustic and density neutron formation properties.

In the period for 2013 to the 2nd quarter of 2014 have been successfully constructed more than 10 similar wells. Esteblished new records: maximum closure – 2403 meters, the length of the longest subhorizontal section reached 1233 meters. Set a record duration of well construction time of 62 days vs 100 planned, which could not been reached before by anyone in the region (formerly similar wells with shorter intervals of subhorizontal sectionhave been constructed in evarage about 150 days). Recently were successfully run two completion liners for 3-stage hydraulic fracturing (MSF) and one of MSF was successfully done. For completion purposes was used OBM with the weighting agent of mikro size, provided an unprecedented stability to settlement for a long time.

This article devoted to the description of technologies and solutions that have been used for the construction of sub-horizontal wells.

Preliminary production index of subhorizontal wells shows that current PI higher than S-shape wells (even with frac).

Positive experience in the construction of subhorizontal wells change plans to develop Achimov deposits and opens new perspectives of hydrocarbon production in the region.
Unique Water Shut-Off Solution for Water Producing Interval in a Horizontal Well Completed with Multistage Fracturing System Using Two CT Inflatable Bridge Plugs
Authors: Golovanev A. S. , Potryasov A. A. , Kovalev V. N. , Yunusov R. R. , Burdin K. V. , Mazitov R. N. , Bravkov P. V. , Serikov D. A. , Klimenko V. N.
Published: September 2014

The widespread application of multi-stage fracturing technology in Russia is already known not only due to increase of production rates and increase of recoverable reserves but also due to premature water flooding of some intervals. Several reasons could lead to that result, while, perhaps, the main one is a breakthrough in the aquifers in the process of the fracturing.

Objective of the job given by the client was to isolate water producing interval in a horizontal well completed with 8-stage MSF completion. To determine position of water-flooded zone, coiled tubing production logging tool (PLT) was used. Based on CT logging data 6th frac port of 8-stage MSF completion was found to be water flooded. Moreover, while total production rate of the well was equal to 500 m3/day (data was received during nitrogen lift while logging) with 95% WC, 68% of total production came from 6th frac port.

This article includes detailed study of planning process, complex and unambiguous decision-making aimed at technical and practical challenges, risk assessment and methods to reduce them, the stages of the work and planning in different situations that arise in the process of water shut-off and received lessons learned.
Anti-Stick-Slip Drilling Strategy for Horizontal Wells in Medium-to-Hard Heterogeneous Rocks
Authors: Kamatov K. A.
Published: September 2014

Though stick-slip phenomenon has been under intent research in recent years, high-level bottomhole and drillstem torsional oscillations still remain one of the main penetration rate (ROP) and tool life limiters in a wide variety of drilling conditions, such as an increasing amount of horizontal drilling with PDC drill bits. The heterogeneity of geological cross-section further complicates drilling environment leading to periodical depth-of-cut (DOC) and torque fluctuations.

The paper represents the study of field-collected drilling data from the challenging application of interbedded medium and hard carbonate rocks. First, similarity of most wide-spread constructions of drillstem in terms of drill string dynamics is discussed. Then, equations for different drill string dynamics zones are given for rotary and PDM BHAs. Finally, an example of drill string dynamics calculations from field data is given for multipart BHA. To account for different stiffness and length of the elements in used multipart assembly at hand, 2 drillstems are picked as boundary conditions for dynamic calculations; one consisting of drill pipes only, the second including BHA of planned length, but consisting of the most stiff element only, e.g. HWDP. The described method allows identification of zones (depth intervals) along borehole measured depth (MD) with high probability of torsional dynamic dysfunction appearance. Different drilling parameters can be applied to the calculation to change these zones’ size and position on MD. Finally, drilling strategy is developed to avoid BHA work in vibration-generating intervals. This can be done by proper and timely adjustment of surface and related downhole drilling parameters to vault over incompatible areas. The described method allows to significantly reduce and prevent negative impact of stick-slip, therefore improving ROP and overall drilling performance.
Considerations for Optimum Inflow Control Devices (ICDs) Selection and Placement in Horizontal Sections
Authors: Akbari Morteza , Gonzalez Jose R. , Macklin Nadine
Published: September 2014

Inflow Control Devices (ICDs) are used as a permanent part of the well completion to control and to effectively equalize the inflow from the reservoir to the wellbore along the length of horizontal section. Key consideration in ICD optimization are good reservoir modeling using in-house and commercially available Petroleum Engineering software, complete geological data from the existing wells and accurate permeability profiles (minimum and maximum permeability values and well test analysis).

Successful design and implementation of ICDs in horizontal sections depends on identifying and evaluating the correct Key Parameter Indicators sets (KPI's). The optimum ICD selection and placement is achieved by evaluating both non-ICD completion as a basic scenario and, a set of scenarios with varying pressure drop through the identified isolated zones along the horizontal wellbore (compartmentalization). Selection is governed by the appropriate ICDs selection and Flow Restriction Ratings (FRR) setting.

The ultimate goal is to the maximize the recovery factor by generating a uniform flow pattern through the drainage area in long horizontal wellbores, despite the differences in the frictional pressure drop from toe to heel, which is of major concern regarding water and gas coning.

In addition to a good understanding of both reservoir behavior and sand control completion technology, the process under discussion will help to overcome the geological challenges and to maximize the production.
Optimization of Cement Spacer System for Zonal Isolation in High-Pressure High-Temperature Wells
Authors: Tabatabaee Moradi Seyyed Shahab , Nikolaev Nikolay Ivanovich
Published: September 2014

Cementing a wellbore is a major stage in well completion and an initiation for production operations. One of the primary objectives of the cementing operations is zonal isolation. For effective zonal isolation and optimum hydrocarbon production during the life of the well, the entire drilling fluid, which presents in the annulus between the hole and the casing, should be removed. Over the years, several practices have been employed to help achieve mud removal and successful zonal isolation. From industry practices, efficient mud removal can be achieved with the use of spacers and flushes before cement is placed. The spacer system is designed according to different conditions including geological condition of the well. With the increasing tendency to drill high-pressure high-temperature wells, the design of robust and stable spacers is becoming more critical. Various spacer systems are available, but they may not be suitable for these conditions. The efficiency of spacer system is largely dependent on the rheological properties of the spacer at elevated temperatures. In this paper based on the laboratory investigations, the performance of specially designed spacer systems, their compatibility with mud systems and mud removal efficiency are compared in various temperatures. The spacers are weighted spacers, which are specially designed to meet the existed geological conditions of the well. The spacers contain a suitable surfactant package to increase its surface cleaning ability, a weighting agent (e.g. hematite) to adjust the spacer's density and a rheological modification agent. The proportions of these components in a spacer system will control the rheological properties of the final mixture, and thus, performance of the spacer. The spacers systems show a reliable performance in a wide temperature range.
The Results of Horizontal Well Drilling Using Invert-Emulsion Fluid at Kharyaginskoe Field
Authors: Khvoshchin P. , Lyadova N. , Iliasov S. , Nekrasova I. , Garshina O. , Kuznetsov A.
Published: September 2014

This work is devoted to the solution of the problem of well drilling on the sediments of the Devonian system known to lots of the world and Russian oil-and-gas regions. The well drilling on the Devonian sediments, especially with the horizontal borehole, is difficult due to the lithological composition and peculiar geomechanic properties of the clay formations composing the drilling intervals. This work covers the approach to solving the problem of keeping the Devonian sediments stability, starting from the integrated study of core of the problem intervals through the end of the testing of the developed technology concepts.

Hydrocarbon-based muds and relating invert emulsions are concerned to be unsurpassed in terms of keeping borehole stability, nevertheless they have got some disadvantages concerning the significant change in their structure-rheological properties during the change in thermobaric conditions. The solution of the stated problems is in the usage of the reagent, described in this report, which is aimed to regulate the rheological profile of the system under high bottom-hole temperature conditions. Due to the nano-size of the polymer particles, contained in the reagent, the filter cake is formed to colmatage micropores and microfractures in the formations as well as to prevent their spread.

The work covers the results of the practical-field testing of the improved invert-emulsion drilling mud formula at Kharyaginskoe oilfield. The leading foreign service company that conducted the drilling mud during the building of the horizontal wells at this oilfield before, has faced the problem connected with the loss of bore hole walls stability while opening the Devonian sediments at the zenith angles more than 60 degrees. The use of the drilling mud formula, presented in the report, has given the opportunity to avoid the problems stated above.

The field testing results, presented in the report, can be useful for the choice and reasoning of the drilling mud formula while constructing horizontal wells on the Devonian sediments by other companies especially those of them working in the Komi Republic and in the Nenets Autonomous District.