bluuebunny/crossref_metadata_2025_split huggingface dataset:
Investigation of Effect of Fracturing Fluid on After-Closure Analysis in Gas Reservoirs
Authors: Soliman M. Y. , Miranda Carlos , Wang Hong (Max) , Thornton Kim 
Published: February 2010

Abstract
Published techniques for analysis of fracture-after-closure data usually assume single-phase flow. These procedures generally rely on the techniques developed for the analysis of buildup tests. Applying the buildup techniques implies that the injected fluid and reservoir fluid have approximately the same properties. This assumption is generally incorrect in case of MiniFrac tests where the injected fluid may be very different from the reservoir fluids. This situation is at an extreme when the MiniFrac test is conducted on a gas reservoir and the injected fluid may be a relatively high viscosity gelled fluid.
This paper briefly reviews the various available techniques for after-closure analysis discussing the strengths and weaknesses of each. Using a numerical simulator, MiniFrac tests are simulated and analyzed for both oil and gas reservoir cases where an aqueous phase is injected as a fracturing fluid. Analyses of the numerically-simulated falloff data are presented. Guidelines for the analysis of such data have been developed and presented.
Field data are also presented. In one case, breakdown, step-rate, and fluid efficiency tests (FET) were performed on a tight gas formation and the data were analyzed. The results of using these various techniques are presented. The consistency of results validates conclusions achieved using the numerically simulated data. In another field case, a test that was performed during drilling was analyzed.
Detecting Thin Lens-Shape Features in Kharita Member in Aghar SW Field Using Multi-Azimuthal Offset VSP, Western Desert, Egypt
Authors: Abdel-Hafez Tarek , El-Makarem Abo , Hosny Mohamed , Ahmad Parvez , Hosny Shady 
Published: February 2010

Abstract
Complex near-surface conditions and subsurface geology pose problems for seismic imaging in Western Desert and require new survey design approaches, sensor technology and processing techniques. In Aghar SW Field in West Razzak Development Lease (Western Desert) the main reservoir is the Bahariya Formation but hydrocarbons were found in some wells also in the Kharita Member.
This paper presents a case study from Aghar SW Field where conventional 3D surface seismic could not resolve the hydrocarbon bearing sandstone layer intercalated within shale in the Kharita Member and the decision on planning an additional development well was very difficult.
Borehole seismic was considered as a viable solution to enhance the seismic resolution and map the extension of a sub-seismic hydrocarbon bearing layer. A cost effective multi-azimuthal VSP survey was designed in Offset VSP configuration placing seismic energy source at different source offsets and azimuths around Aghar SW 5 ST Well.
Data were acquired using 3-component multi-shuttle Versatile Seismic Imager tool as downhole geophone and vibroseis as seismic energy source. Multi-component processing was carried out in Walkaway VSP configuration combining the data optimally. VSP high resolution images resolved successfully the thin lenticular productive sandstone layer and the location for Aghar SW 6 Well was chosen accordingly.
Special Core Analysis for Integrated Static & Dynamic Reservoir Modeling Bapetco NEAG1 Field
Authors: ElBelisy Mohamed , Bakr Ahmed , Ahmed Ismail , Albaaj Elena , Wahdan Maamoun 
Published: February 2010

Abstract
NEAG1 is one of Bapetco fields located in the eastern part of the Western Desert, close to Qarun field. Special Core analysis has been used in an integrated way to optimize parameters used in Static and Dynamic reservoir models. The methodology of selecting the adequate core plugs was an integrated work of PP, PG and RE engineers to ensure optimal selection of samples representative for the reservoir. Routine Core analysis and core photos, logs, SEM were used in the selection procedures.
The results are being integrated into the Static and Dynamic model and they show an improved prediction of reservoir properties.
Rheological and Core Flood Studies of Gelled and In-Situ Gelled Acids
Authors: Gomaa A. M. , Nasr-El-Din H. A. 
Published: February 2010

Abstract
Polymer-based acids, which have been used in the field for decades for acid diversion, were examined extensively through the literature. Recent lab work indicated that these acids could cause damage under certain conditions, while field data gave positive and negative results. The behavior of these acids is not fully understood. Permeability enhancement, radius of wormholes, diversion efficiency and damage mechanisms are determined in part by the rheological properties of these acids. Rheology of In-situ gelled acids exhibit strong viscoelastic properties at pH greater than 2. Therefore, the objectives of this study are to determine the elastic and viscous properties of these acids, how these properties change as the acid reacts with carbonate formations, and what their effect on acid diversions.
Experimental studies were conducted to measure the rheological properties for polymer-based acids using oscillatory rheometer. To the best of our knowledge, this is the first time that the viscoelastic properties were measured for these acids. Measuring the elastic modulus (G') and viscous modulus (G") were done using two tests: Dynamic sweep tests, which were used to define the shear rate dependent response; Creep tests, which were used to define the time depended response.
The behavior of gelled acids was independent of pH while the behavior of in-situ gelled acids varied with pH. Gelled and live in-situ gelled acids had weak viscoelastic properties while partially neutralized (pH 3.2) in-situ gelled acid had strong viscoelastic properties. Polymer filter-cake formed in case of gelled acid injection while in-situ gelled acids didn't form any polymer filter-cake. This is because of the in-situ gelled acid formed a thin layer of gel that minimize the leak-off which prevent the build of polymer filter-cake. The strong viscoelastic properties determine the effectiveness of diversion. As elastic properties increases, the formed gel will sustain around the wormhole and plug it. This will force the next acid stage to penetrate the weakest point and change its direction. For gelled acid, the inlet face washout and the polymer filter-cake reduced the core permeability to zero by plugged the core holder inlet during the water flow back. However after removing the plugging effect, a permeability enhancement was much higher than in-situ gelled acids. The wormhole obtained in case of gelled acid was nearly linear and thinner than the wormhole created by in-situ gelled acid. The results obtained can be used to better design matrix acid treatments when polymer-based acids are used in the field.
Research of Gas Separator with Disperser Influence of ESP Work and Increase of Well Operation Efficiency by the Use of ESP
Authors: Mokhov Mikhail 
Published: February 2010

Abstract
In recent years there is a tendency of standing increase of ESP share in performance stock of oil recover companies. At the same time there is an increase of oil production from drowned wells observed in consequence of universal application of water flooding and depletion of most of the large deposits. The average water cut of recovered products at pump operation is at present from 80 to 85 per cent. As is known, one of the complicating factors of steady operation of ESP is free gas inflow into the pump. For the protection of ESP against free gas harmful effect on the oil-fields, gas separators are widely used because they allow to separate some of the gas into the annular space. When water cut increases, the quantity of free gas in the flow stream drops, and it becomes possible to apply a disperser, which is required for the generation of fine liquid-gas mixture which, on reaching the inlet of ESP, decreases free gas effect on the pump operation. The application of dispersers is also well grounded for zero water-cut oil fields with moderate-size gas oil ratio.
Frequently, in order to protect ESP from an adverse gas effect, gas separators are used, which drop part of precipitated gas into the annular space. A considerable part of associated gas in the annular space under certain conditions can lead to the formation of hydrate and paraffin-hydrate blocks which stop up the annular space and create conditions for both the separator and the ESP work breakdown, down to the pump starvation. It is noteworthy that the gas dropped in the annular space doesn't do raising fluid operation. This work is done by the pump, which leads to power consumption and production cost increase, as well as error-free running time decrease.
Planning the Subsurface Modeling Tool for the Full Field Life Cycle and Influences of Multi-Disciplinary Integration on Static Modeling: Examples from the Sitra Field, Egyptian Western Desert
Authors: Abd El Rahman Hassan , Wahdan Maamoun , Le Varlet Xavier , Toukhy Ahmed 
Published: February 2010

Abstract
This paper demonstrates how a holistic modeling approach and multidisciplinary integration were used to plan the longer-term development of a recent, promising discovery.
The Sitra field was discovered in 1983. Three subsequent appraisal wells discovered additional reservoirs. The wells also demonstrated that sand prediction and lateral connectivity would be a dominant challenge to field development..
A joint SENV/BAPETCO/EPTS multi-disciplinary project was initiated to help plan the further appraisal and development of the field. The static model was to become the backbone of the subsurface work. The model had to be useable for both immediate and longer term field development planning and had to fulfill the requirements of various departments.
Well engineering safety guidelines required the conservative 3D rendition of the main bounding fault. Petroleum engineering required the most realistic structural model for the main area of the field and boundary fault.
In the main reservoir, multi-disciplinary integration played a key role in the construction of the geological model. The background was provided by a recent regional study. AVO inversion provided results that could only be used qualitatively, but a seismic Stratigraphic interpretation integrated with sequence Stratigraphic well correlation and sedimentlogical core description did indicated the potential presence Tidal Channel/Bar system which fit in the context of all other subsurface data. The resulting conceptual model is of an Delta/Submarine depositional system in which high quality channel sands are concentrated in two NNE-trending systems. The 3D Facies model was constructed accordingly.
This static model was fully history matched and used to forecast alternative development scenarios for this Oil/Gas reservoir, providing a strong basis for future reserves reassessments.
Integration across disciplines, organizations and locations was critical in project delivery. The common 3D Grid helped in sharing information between different teams and reinforced cooperation. Remote working tools were important in the transfer, handover and sharing of information and models.
Developing National Talent to Meet Future Production Opportunities in Egypt
Authors: Youssef Ahmed Alaa , El-Refai Hashem , El-Tobgy Sherin , Beare David , van den Broek Ton 
Published: February 2010

Abstract
The Badr El-Din Petroleum Company ("Bapetco") has always invested in developing the competency of its field and well operations staff with significant success achieved over the last 25 years of operations. Growing Bapetco's and Egypt's National talent resource is essential to continuously improve operational excellence in all activities and to implement advanced technologies to sustain and increase production. Historically, competency development was supported by a combination of on-the-job training and formal classroom training programmes. These competency development methods have been augmented over recent years by blended learning techniques and formal competency assessment to recognise and reward achievement of levels of skills and experience within a formal mentoring and accreditation framework. This paper details the remarkable progress made so far and Bapetco's approach to achieving a sustainable and internationally recognised competency development programme for well and field operational personnel in Egypt, and beyond.
The paper describes what has so far been achieved and what initiatives are underway to ensure that Bapetco's and Egypt's current and future competency requirements in the well and field operations domain are met.
Results/Conclusions - The Bapetco Wells section, i.e. Well Engineering (WE) and Completions & Well Interventions (C&WI) discipline has always been supported by internationally recognised accredited competency development programme (Shell's Drilling Round I and II). This has supported Bapetco business aims and led to a doubling of the number of drilling rigs supervised by qualified National Drilling Supervisors, and recognition of Bapetco for its international accreditation of its first Well Services Supervisors. This has also benefitted the Egyptian oil and gas sector by supplying the Well Engineering and Well Services discipline with a steady stream of qualified engineers. Graduate engineers benefit greatly from progressive competency development, thorough blended learning, and professional accreditation to attain progressive competency profiles. The benefits of this approach have been identified and the drive is to continue to extend the development and accreditation programmes across the Wellservices and Field Operations disciplines to make sure that National talent is groomed professionally to take on the leadership of Bapetco's future oil and gas developments, and make an important contribution to the wider Egyptian oil and gas sector.
Using Wellbore Stability Analysis to Improve Drilling Performance: Case Study from the Western Desert, Egypt
Authors: Van Steene Marie , Povstyanova Madgalena , Al-Attar Haitham , El Gheit Diaa Abu , Abutaleb Moamen , Lantz Jim , Abdel Kareem Salah 
Published: February 2010

Abstract
Multiple wellbore stability projects in the Western Desert of Egypt identified a strong sensitivity of the breakout gradient to wellbore inclination and a weak sensitivity to wellbore azimuth, from the Abu Roash to the Alam El Bueib formations. The breakdown gradient shows strong sensitivity to both wellbore inclination and wellbore azimuth. Tensile failures are a problem only in high deviation wells (deviation more than 55–60°) where the breakdown gradient will in general be lower. For highly deviated wells, the occurrence of tensile failure can be reduced by drilling close to the minimum horizontal stress direction.
Breakout can be tolerated to some extent, so planning the drilling mud weight to completely eliminate it is not necessary. The extent to which breakout can be tolerated depends on the well deviation, as cuttings become more difficult to evacuate as the well deviation increases.
As losses are very common in most of the Western Desert formations, the optimum drilling mud weight should be formulated as a balance between the risks caused by breakout and mud loss.
Understanding the main causes of rock failure and applying the recommended failure mitigation measures resulted in successfully drilling four deviated wells in the area.
Combining Selective Stimulation with Tailored Perforating Improves Injection Profile in a Carbonate Reservoir: A Case Study
Authors: Al-Gub Jamal M.A. , Horikoshi Tsuneo , Ichikawa Kazutoshi , Salsman Alan , Ali Neyaei Fardin , Vasquez Fidias 
Published: February 2010

Abstract
In a multi-layer heterogeneous carbonate reservoir in which production and injection is being carried out, one of the biggest challenges faced is to produce/inject evenly from/to the different layers. At elevated temperatures this heterogeneity limits the success of conventional stimulation techniques. A novel acid diversion technique involving selective stimulation and tailored perforation design techniques was applied in an offshore UAE well to improve injectivity in a multi-layered heterogeneous carbonate reservoir.
The well in question was re-completed from a dual string water injector well to a single string gas injector re-perforated in four different sub-zones. Well test and production logging data were used to estimate permeability and flow profile before the workover. These data were then used to run NODAL analysis, stimulation simulation, and perforation simulation models. The final workover proposal called for: Perforation over the same interval as was previously perforated using different gun and charge sizes to establish controlled injection based on the different zones permeability.Optimized coiled tubing (CT) selective stimulation using high strength retarded acid pumped in stages with a self diverting acid.
The well injection performance was dramatically improved as evidenced by the gross injection value and the injection profile obtained in a post treatment production logging run.
This paper details the planning, execution and final evaluation of this job which is unique in that the same interval was tested twice, before and after workover, after being completed using different perforating and stimulation techniques.
Case Histories of a New Family of Setting Tools for Ultra-Deep and High-Temperature Well Conditions
Authors: Kessler Calvin , Hill Jim , Housden Richard 
Published: February 2010

Abstract
A new generation electro-mechanical downhole power unit for setting and retrieving packers, bridge plugs, whipstocks, subsea tree plugs, and other downhole devices has been recently developed and deployed. The new Downhole Power Unit-Intelligent, DPU®-I tool, is designed to operate at high temperatures and extremely high pressures (400°F, 30 Kpsi) and to provide up to 100 K-lbf setting force. The increased force for either setting or retrieving downhole devices is independent of hydrostatic pressure and provides an alternative to jointed pipe or coiled tubing interventions, which were previously required to obtain high setting forces. New to the industry is the ability to monitor the downhole line tension, stroke length, setting force, the rate at which the force is being applied during the setting operation, and force at which the DPU-I tool detaches from the downhole device in real time at the wellsite or remotely by means of global satellite communications. This new functionality enables well-completion experts to remotely monitor the setting or retrieval operations 24 hours per day, seven days per week. It also provides a record of the setting operation for risk mitigation and for developing and improving best practices. This new downhole power unit conforms to our Digital Asset® workflows used to model, measure, and optimize customer assets.
The slow-controlled setting operation enables the slips or other anchoring mechanisms in the device to be set and to fully engage the casing/tubing and for the elastomer sealing elements to conform to the casing or tubing ID. This function is extremely critical in highly-deviated well conditions and when using casing or tubing with high rockwell hardness. Unlike setting devices that use explosives, military or governmental escorts are not required. In addition, single-lift heli-operations can be used. This tool does not require radio silence operations, and there is no non-productive time associated with tool redressing between runs. Tool sizes are available for well intervention in 2–3/8-in. tubing through 13-3/8-in. casing and can be tractor-conveyed in high-angle or horizontal wells.
Application of Specific Designed Bits and Eccentric Reamer for Deep Gas Wells in the Nile Delta Enables Operator to Achieve Significant Cost Savings on Drilling Wells
Authors: El Seginy Ahmed , Bohannon Ricky , Fayez Mohammed , Ekstrom Darren , Hussain Sameh 
Published: February 2010

Abstract
In 2008 &2009, Dana Gas continued on their deep Gas development program in the Nile Delta region of Egypt. These wells in the past had proven problematic in drilling because of high formation pressures and compacted shale in some intervals & almost the aligned curves (very narrow window) between the pore pressure & fracture gradient in other intervals.
Similar wells drilled in the past required both roller cone and PDC bits to complete the various sections. Because roller cone had unacceptably low ROP, Dana Gas determined PDC would offer the best option to efficiently drill these sections, therefore offering the best chance for success. Contingencies were considered for fallback to roller cone if necessary. Also in the contingency was the use of eccentric Ream While Drilling tool to enlarge the hole across a high pressure zone which would enable us to set an expandable liner and continue drilling to TD with a larger hole and avoid potential problems associated with slim hole drilling.
In the preplanning stage, Dana Gas drilling team closely examined new technologies which would allow us to achieve our goals, especially drilling the demanding deep highly pressured zones. The entire BHA was engineered to ensure the ROP and directional requirements would be met. A team was organized to aggressively seek technology/best practices that would efficiently deliver well objectives. The team identified the poor ROP in the compacted shale sections to be a primary obstacle as well as dealing with the potential zone with high pore pressure. BHA and PDC bit technology was a key focuses in optimizing the 12 ¼″ and 8 ½″ sections. Due to this careful planning and collaboration between Dana Gas and service providers, objective in the 12 ¼″ section on SHARABAS-1 and 8 ½″ section on EL BASANT-3 wells drilling with new designed PDC was achieved by increasing ROP and realizing significant savings. By applying new technology the 12 ¼″ section on SHARABAS-1 was drilled 328% faster with a savings of US$ 122,445.00 and the 8 ½″ section on EL BASANT-3 was drilled with a 37% higher ROP with a savings of US$ 34,517.00 than the direct offsets.
High Resistivity High Water Saturation Addressing the Problem to Avoid Water Production
Authors: Salah A.. , Hassan S.. , Sabra M.. 
Published: February 2010

Abstract
Belayim Land field is one of the oldest and largest oil fields in Egypt. It produces oil from many sandstone reservoirs. Oil is produced from 4-30 ohm-m resistivity in Belayim Formation, while to the contrary, in Rudeis Formation, 70–80 ohm-m resistivity is producing water. Rock characterization program was planned for Rudeis Formation using core material. It includes porosity, permeability, thin section description, SEM, wettability, relative permeability and capillary pressure by mercury injection to obtain pore throat size distribution. The wettability of the reservoir rock was determined by Amott method and proved to be strongly oil wet. The wettability controls the position of fluids within the pore network, where in oil-wet the water saturation distributed as poorly connected droplets within the macro-pores and filled the micro-pores.
To simulate the saturation history of the reservoir, restored-state samples at irreducible water saturation were flooded with water to perform electrical resistivity measurements. Non-linear curves were obtained during the electrical resistivity measurements. Two saturation exponents (n) values were proposed to reflect the mechanism of forming continuous water film from the water droplets. The inflection point between the two (n) values was used to determine the resistivity cutoff below which water is produced. In addition, it represents the water saturation cutoff which was confirmed from the calculation of fractional flow of water from relative permeability measurements. The production data confirm the use of variable (n) to monitor the water saturation in oil-wet reservoirs.