bluuebunny/crossref_metadata_2025_split huggingface dataset:
Measurement of Oil-Water Ratio and Formation Porosity Using Dielectric Spectroscopy in Borehole Environments
Authors: Eltsov Timofey , Dorovsky Vitaly , Golikov Nikita , Tabarovsky Leonty , Epov Michael 
Published: September 2014

Abstract
Finding water-oil rations in a saturated porous reservoir by means of EM logging is established on the possibility of imaging the dielectric spectra by the borehole inductive probe, identification of the components of the reservoir from these dielectric spectra, and determination of the water-oil ratio and porosity from the relaxation parameters. To find the water-oil ratio and porosity in the reservoir using dielectric spectroscopy, the mixing formula is often used. This formula expresses the complex dielectric permittivity via complex dielectric permittivities of the subsystems. Such a formula works in the MHz frequency range of the electromagnetic field. However, there are many problems associated with applying the mixing formulae. First, relaxation parameters of the Maxwell-Wagner polarization for the water-saturated porous media often fall outside of the domain where the Maxwell-Wagner polarization exists in reality and, as a result, the mixing formula is deemed inapplicable. Second, the number of relaxation parameters of the water-saturated porous medium (e.g. in the case when the formation is saturated with both water and oil) is typically lower than the number of dielectric degrees of freedom for the subsystems. Therefore, alternative methods are necessary to calculate bulk fractions of the subsystems present and formation porosity.
The lab study of dielectric spectra of sandstones and dolomites saturated with a water-oil mix demonstrates that elements of a qualitative difference between a water-saturated reservoirs can be introduced to that saturated with a water-oil mix using the acoustic frequency range of the electromagnetic field. This difference is from the huge values of dielectric polarization unrelated to the Maxwell-Wagner polarization. This paper shows that Havriliak-Negami dielectric spectra enable the introduction of a natural measure of water saturation in the samples saturated with a water-oil mix find the water-oil ratio. As a result, the universal dependence for finding porosity of the samples saturated with a water-oil mix is used. Knowledge ofa priori information regarding the material content of the reservoir is not necessary. The water-oil ratio and porosity depend exclusively on the Havriliak-Negami polarization parameters, which can be found univalently from the characteristic values of the parameters of the measured dielectric spectra.
A Methodology for Early Detection of Semi-Permeable Filtration Barriers
Authors: Karger Mir , Trofimov Dmitry , Eminov Adalat , Myasnikov Ivan , Zakharov Alexander 
Published: September 2014

Abstract
The faults are universal in the petroleum reservoirs. Some of them are Semi-Permeable Filtration Barriers (SPFBs) such that a SPFB becomes fluid/gas permeable if a pressure threshold is exceeded. This may cause sudden changes in reservoir structures and, eventually result in negative impacts on production. This paper deals with early SPFB detection and characterization. We consider some case studies of reservoirs with SPFBs, and present a new methodology for SPFB detection. This includes the following groups of methods: mapping of surface responses to deep geodynamic and fluid-dynamic events (incl. SAR interferometry), 3D-mapping of faults in the reservoir and adjacent formations, separation of SPFBs from other dislocations. The methodology implementation is demonstrated with the case study of underground gas storage.
Uncertainty Analysis of Main Development Targets of Unique Gas-Condensate Field
Authors: Ilyushina A. S. , Serebryakov V. V. , Kurkin A. A. , Gataullin T. I. , Medvedev S. G. 
Published: September 2014

Abstract
In the presented work an uncertainty analysis was applied for the unique multilayer field with a complex structure. Main uncertainty parameters as a structural mapping, gas-water contact, petrophysical correlations, lithology distribution were assessed for an influence on reserves and gas production. Much attention was directed to the calculation of structural mapping uncertainties. They were assessed using stochastic modeling – generation of structure error map based on estimated error from seismic data. Each map consists of low and high frequency maps depending on distance from exploration wells. Stochastic algorithm SGS (sequential Gaussian simulation) was performed for the maps construction. Results of the work were applied to determine the influence of the main uncertainty parameters on the production forecast.
This article is dedicated to one of the company's unique oil and gas fields with a complex geological structure, which is in preparation for trial production stage. Productivity is determined in 32 layers (109 accumulations).
The aim of this work is to assess the impact of main uncertainties on forecast level of hydrocarbon production and geological reserves of the field.
Recovery Increase by Permanent Downhole Gages Data. Western Siberia Field Case Study
Authors: Gulyaev D. , Kokurina V. , Melnikov S 
Published: September 2014

Abstract
Permanent downhole monitoring gages (PDMG) are significantly improving. Gages reliability and accuracy are increasing. At the same time there are still many in Russia believe that the organization of continuous monitoring – is branding costs that do not bring profits.
The paper presents an example of one of the Western Siberia fields, where the effect of PDMG wide implementation is easy to see. Based on the analysis results of the monitoring of downhole parameters using PDMG, which are installed in all the wells in 2012, large-scale optimization of production enhancement operations have been done to improve oil recovery to 0.09 relative percent.
Optimization of Operation of the System Reservoir-Well-Pipeline-GTU Based on the Integrated Modeling
Authors: Bikbulatov S. , Smirnov A. , Buleiko V. , Mukminov I. , Romashkin S. 
Published: September 2014

Abstract
In this paper, the authors address the issue of optimization of gas production system reservoir-well-pipeline-GCTU (gas & condensate treatment unit) using integrated modeling. Authors describe the method of calculation, the setup process and modeling of each element of the system and the various methods of optimization. Special attention is paid to the automatization of the engineer interaction with models, modeling of the GCTU and optimizing the mode of operation in conjunction with other elements of the system.
Integrated Compositional Model of Grachevskoe Field
Authors: Gimazov A. A. , Sergeev E. I. , Nikolaev V. A. , Sadreev E. A. 
Published: September 2014

Abstract
Grachevskoe oil field, Republic of Bashkortostan, has a unique development history with the application of an EOR technique which involves injecting a mixture of natural gas and associated petroleum gas into the reservoir. The injection fluid is sourced from this field and a cluster of nearby fields united in a single gathering and processing system. A production stimulation technique applied to the reservoir also included a series of subsurface explosions to create a network of induced fractures. A slug of natural gas liquids was pumped into the reservoir to improve the displacement efficiency prior to gas injection. The paper presents a comprehensive analysis of the production field data and core analysis data and describes a static and compositional dynamic model of the reservoir. The project was elaborated by a multidisciplinary team of specialists and their close cooperation resulted in a dynamic simulation of a fracture network within the reservoir, improved understanding of complex mechanisms driving oil-gas displacement, the effect produced by the changes in the type of the injection fluid or injection pattern and current in-situ oil and gas distribution. The next step in the project involved an integrated compositional model which also included the surface facilities and well-scale models. The combined model was calibrated against the limitations of the surface infrastructure. The integrated model was used to optimize the field development plan subject to the current conditions in the reservoir and the availability and capacity of the gathering and processing system to which the field is connected.
Comparison of Geological and Technical Measures Effectiveness for the Upper Jurassic Conditions of Western Siberia
Authors: Alexeevich Sintsov Ivan 
Published: September 2014

Abstract
In developing the Upper Jurassic deposits of Western Siberia (Nizhnevartovsk and Surgut arches) are widely used hydraulic fracturing and horizontal wells, however, conclusions about the effectiveness of these two technologies are ambiguous. The purpose of this paper is to compare the effectiveness of vertical wells with hydraulic fracturing and horizontal drilling. To fulfill the tasks were carried out hydrodynamic, statistical and economic calculations. Our studies demonstrated that the use of hydraulic fracturing and horizontal drilling conditions for Upper Jurassic layers can improve economic development indicators, as well as to increase the oil recovery period for the cost-effective development. The economic efficiency of drilling horizontal wells is much higher compared to the use of hydraulic fracturing to vertical wells, in particular for water zones. The results and the approach can be used in the design and justification of systems development in various productive oil reservoirs. Thus, the design of the development is necessary to provide the use of regular grids using horizontal wells.
Towards Enhanced Steam Management of SAGD Wells Using Reliable and Permanent Real-Time FBG-Based Thermal Monitoring
Authors: Ficocelli Peter , Gonzalez Luis E. , Vincelette Andre , Caporuscio Robert , Bostick Tad , Shand Mike 
Published: September 2014

Abstract
The scope of this paper is to present the analysis and use of permanent real-time monitored data from ultrahigh-temperature, steam-assisted, gravity-drainage (SAGD) wells with the objective of achieving steam control. Multiple applications from live wells will be presented to illustrate the value of permanent reservoir monitoring in the circulation and SAGD production cycles. Case studies will be presented from SAGD wells where actual real-time data enabled active management of critical processes. The introduction of multipoint systems based on high-density fiber Bragg grating (FBG) has made real-time permanent monitoring possible.
High-temperature thermal monitoring systems based on FBG array technology have been successfully introduced for monitoring SAGD wells. These systems offer a practical means to increase the number of sensing points for better spatial characterization of the well than with other sensor solutions and with a step-improvement in reliability. These advantages tend to overshadow another key performance aspect of these systems: delivering improved data quality in terms of absolute accuracy and resolution, with a sub-Hz processing rate to deliver data in real time. Greater thermal visualization enabled by this technology is observed in analysis of field data that verifies the expected SAGD operations. Field data from operating SAGD wells will be presented to show the improved thermal imaging of the wellbore that these systems provide.
Horizontal Well Monitoring Based on Temperature Profile Measuring with Distributed Temperature Sensors (DST)
Authors: Kaeshkov I. S. , Kremenetskiy M. I. , Buyanov A. V. 
Published: September 2014

Abstract
In current research authors look for and analyze an alternative to traditional production logging tools (PLT) and high-technological multisensor tools in horizontal wells. Trancient temperature profiles measurements using fiberoptic distributed stationary sensors (DST) are chosen. Functionality analysis of this method is carried out within a mathematical model.
Authors conduct mathematic modeling of heat and mass transfer in horizontal well. It demonstrates that a certain interpretation can be done if the measurements are held during transient processes. These processes occur when the well is started, stopped or when the regime of production is changed (different rate, choke or ESP frequency). However such measurements are not so technically simple to realize, because of low duration of these processes (up to first dozens of minutes). Distributed temperature sensors have a high potential for successful measurement of such processes.
Most of the typical cases of horizontal well inflow are calculated and deeply analyzed. It resulted in smart methodological approaches to measuring, interpretation algorithm and application limits. The essential significance of the research is deep understanding of DTS information capacity and improvment of the procedure of running the test and interpretation methods.
Theory and Practice of Acidizing High Temperature Carbonate Reservoirs of R. Trebs Oil Field, Timan-Pechora Basin
Authors: Folomeev A. E. , Sharifullin A. R. , Vakhrushev S. A. , Murinov K. Yu. , Akimkin A. V. , Lenchenkova L. E. , Nabiullin R. M. , Federov A. I. 
Published: September 2014

Abstract
The oil reservoirs of R. Trebs field are predominately heterogeneous carbonates with a well developed network of natural fractures, high formation temperature and high concentration of resins and asphaltenes in the produced crude.
Such complicated reservoir conditions entail integrated acid treatment engineering and design to include physical and chemical analysis of acid compositions, formation fluids and reservoir rock; physical simulation of acidizing on core from target intervals and numerical modeling of the optimum acid job design.
The conducted research supported the selection of the optimum acids for the geological and engineering conditions of R.Trebs oil field to secure better compatibility with the formation fluids from the target intervals, lower corrosion activity and retarded reaction rate. The findings also identified the range of critical values for permeability and mineralogy of the rock whereby acid flows through a reservoir rock in a growing dominant wormhole.
Based on the literature survey a semi-empirical model was chosen which describes the growth of a wormhole. The model was calibrated against the actual reservoir conditions of R.Trebs field using flow test results and reaction kinetics studies on the rock samples from the given pay zones.
The integrated approach introduced for acid job design can be applied to achieve the following: —select application or usability criteria of an acid job for a given field;—select optimum acids to secure minimum risks of primary and secondary formation damage and optimum reaction rate;—implement engineering optimization of acid job design by the identification of its most efficient parameters;—forecast post-acid production and other field performance indicators.
Monitoring EOR and Well Stimulation Techniques by Oil Optical Properties Measurement
Authors: Rybakov A. A. , Guskova I. A. , Gabdrakhmanov A. T. 
Published: September 2014

Abstract
To provide the efficient oil reserves development it is critical to select the technology control method that will fully meet field conditions.
Optical method to control the efficiency of applied technologies is a reliable technique based on the analysis of oil light absorption factor.
To assess the effect of enhanced oil recovery techniques on well-stream optical characteristics we analyzed oil samples from the Romashkinskoye field wells (North-Almetyevsk Area) where hydrophobic emulsion, weak polymer solutions, and acid composition have been injected.
The integrated analysis of geologic data and oil optical characteristics before and after hydraulic fracturing has been performed to assess the effect of frac jobs on both new and residual oil reserves development.
Correlation dependence between produced oil volume and its optical characteristics has been identified. The integrated analysis showed the decrease of oil light absorption factor after frac jobs which suggests the fluid flow change and the development of by-passed zones. In other words, this means the improved sweep efficiency. Based on producing well data, hydraulic fracturing resulted in improved residual oil displacement and, consequently, in increased sweep efficiency. Based on the integrated analysis data it has been concluded that optical analysis of oil samples is a proximate reservoir management method and a precise tool to assess the efficiency of the above-mentioned enhanced oil recovery techniques in the development of by-passed reserves.
The technology of integrated oil optical characteristics analysis to control the efficiency of EOR and well stimulation techniques continues to be improved.
Procedure for Analysis of Waterflooded Dual Permeability Reservoir Performance by Example of Bashkirian Deposit, Romashkinskoye Oil Field
Authors: Akhmetgareev Vadim , Ibatullin Ravil 
Published: September 2014

Abstract
A method for assessment and reservoir management of waterflooded fractured-porous reservoirs has been developed. The method has a wide range of applications, from history matching in a research laboratory to selection of optimal well operating practices in the field.
Integration of a large number of parameters into one coefficient, specific imbibition rate, makes it possible to assess reservoir development without carrying out well tests, well logging, or laboratory research. The only information that is needed is water front travel time from injection to producing wells. In Tatarstan, fresh water was injected in most of the fields. Time of injected water arrival was determined from decrease of density of produced water.
To exemplify the method, two pilots in the Bashkirian Deposit No. 302 of the Romashkinskoye field including 25 producing and 3 injection wells were selected for the project. Distribution of the specific rate of imbibition was analyzed; well handling plan to ensure uniform reservoir depletion has been worked out. The rate of imbibition of the dual-permeability Bashkirian reservoir is most sensitive to production rate or well intake capacity, rock blocks’ sizes, rock permeability, formation thickness, and preferential water-wetting angle. The effect of capillary imbibition of waterflooding for distances between the injector and the producers more than 500 m is almost lacking. Maps have been constructed schematically representing distribution of the specific imbibition rate and blocks’ linear sizes from injecting to producing wells.
Beating the Odds with Channeling in ERD Well Cementing: Solution to Persistent Channeling Problems
Authors: Osayande Victor , Isgenderov Islam , Bogaerts Martijn , Kurawle Irfan , Florez Pedro 
Published: September 2014

Abstract
The drive to recover hydrocarbons from difficult to reach reservoirs and optimize production is taking center stage in the Exploration and Production industry. Complex wells are being planned which push the existing technology to limits. The success and longevity of such wells depends upon providing good zonal isolation and sound well integrity for the complete life cycle of the projects. Cementing the wells in a narrow pressure regime without losses and overcoming challenges for optimum zonal isolation presents a unique test to the industry.
The Extended-Reach-Drilling (ERD) wells drilled in the Caspian Sea prior to 2011 have historically seen inadequate zonal isolation in the long intermediate section due to channeling of cement during placement; consistent with directional profile of the wells. Remedial cementing was needed in some cases before the next phase of the well.
As the acceptance criteria for well integrity becomes more stringent, the onus lies on achieving zonal isolation during primary cementing through a combination of optimized cement placement and mechanical barriers. This paper presents the investigative approach towards earlier jobs and the recommended suggestions which led to improvement that was confirmed by cement evaluation logs. The authors present case histories with lessons learnt during the course of implementing the new approach to cementing design and the success of achieving adequate cement coverage across potential flow zones.
Application of the Intelligent Control Systems for Horizontal Well Placement
Authors: Kolchanova Irina 
Published: September 2014

Abstract
Development of new fields of hard-to-recover hydrocarbons has led to the necessity of using new expanded and more informative logging suites. We have started to develop fields with more complex geological structure (seismic faults, several transitional areas in the section, etc.) and more complex lithology of formations. Currently there is a need to drill horizontal wells in demanding geological conditions. Now a standard set of methods is not enough and there is a growing necessity to improve the LWD suite. The conventional gamma-ray logging is continuously supplemented with new methods – density neutron logging, array resistivity logging, spectral gamma-ray logging, boundary mapper, and acoustic logging.
Horizontal drilling with geosteering is more often preferred, as drilling with pre-approved profile may be ineffective in demanding geological conditions. It is important to timely receive comprehensive information of the reservoir properties, when using geosteering in unconventional formations. Therefore it is necessary to use the most appropriate logging suite for evaluation of the lithology, and permeability and porosity properties, depending on the geological situation.
Our company successfully performs horizontal drilling in fields with high degree of reservoir uncertainty (facies replacement, lateral heterogeneities, etc.), drilling for shale oil and gas (including equivalents of Bazhenov formation in the USA). The main target is the maximum exposing of the reservoir producing section, and this task is successfully performed.
This study is an overview of practice in the application of expanded LWD suite for intelligent drilling of horizontal wells. For the first time ever we have the possibility to determine the rock natural radioactivity spectrum while drilling using the three-component analysis of Th, K, U. This helps to determine the nature of rocks radioactivity and to effectively drill horizontal wells in unconventional reservoirs with increased natural radioactivity.
Development of Universal Application for Drillstring Dynamics Simulation
Authors: Tikhonov V. S. , Safronov A. I. , Valiullin Kh. R. , Bukashkina O. S. 
Published: September 2014

Abstract
One of the most topical problems of drilling mechanics is development of a software program for 3D string dynamic simulation in a 3D well on various operation regimes with maximum account of all external factors.
The paper describes the results of long-term development of general-purpose DYNTUB software designed for string dynamic simulation. The software calculates: String torque and drag;Drillstring lateral and torsional vibrations;Drillstring buckling and whirling;Well path while drilling in sliding regime and in rotary regime with Rotary Steerable Systems (RSS) or systems controlled by downhole motor angular velocity modulation;Standoffs between the casing and the wellbore wall with various centralizers.
The software is based on the stiff string dynamic model. It accounts for deformation of the wellbore walls contacted by the string, initial drill pipe bending, PDC bit interaction with the bottomhole under downhole and pore pressure, rock anisotropy, refined multicomponent string friction model, etc.
The software proved applicability of the "soft" drill string model to calculate torque and drag, enabled study of multicomponent friction effects on string buckling, well path calculation while RSS drilling, and solving other complex problems of drilling mechanics.
Software efficiency is demonstrated based on case studies; the paper also includes results of comparative analysis using data from other references.
The software is designed for expert analysis of drilling, casing, coil tubing and similar object parameters while well drilling and completion.