bluuebunny/crossref_metadata_2025_split huggingface dataset:
Flow Enhancement Characterizes Design of Polycrystalline Diamond Cutter Bits
Authors: Kuhn Karl O. , Forrest Scott 
Published: December 2007

ABSTRACT
The design and development of a drag bit that utilizes polycrystalline diamond drill blanks requires careful attention to hydraulic design features. For optimum performance and service life, the polycrystalline diamond drill blanks must be kept cool and clean. These critical hydraulic requirements, vital to the survival of the diamond drill blanks, were resolved by optimizing flow velocities across the cutters as well as with the proper distribution of flow volume. This was accomplished with strategically located flow re-strictors and the incorporation of numerous interchangeable carbide jet nozzles.
Field test results of polycrystalline diamond cutter bit runs in Louisiana and Texas show that significant savings can be realized by using these bits in specific drilling situations.
Evaluation of the Gas Production Potential of Marine Hydrate Deposits in the Ulleung Basin of the Korean East Sea
Authors: Moridis George J. , Reagan Matthew T. , Kim Se-Joon , Seol Yongkoo , Zhang Keni 
Published: December 2007

Abstract
Although significant hydrate deposits are known to exist in the Ulleung Basin of the Korean East Sea, their survey and evaluation as a possible energy resource has not yet been completed. However, it is possible to develop preliminary estimates of their production potential based on the limited data that are currently available. These include the elevation and thickness of the Hydrate-Bearing Layer (HBL), the water depth, and the water temperature at the sea floor. Based on this information, we developed estimates of the local geothermal gradient that bracket its true value. Reasonable estimates of the initial pressure distribution in the HBL can be obtained because it follows closely the hydrostatic. Other critical information needs include the hydrate saturation, and the intrinsic permeabilities of the system formations. These are treated as variables, and sensitivity analysis provides an estimate of their effect on production.
Based on the geology of similar deposits, it is unlikely that Ulleung Basin accumulations belong to Class 1 (involving a HBL underlain by a mobile gas zone). If Class 4 (disperse, low saturation accumulations) deposits are involved, they are not likely to have production potential. The most likely scenarios include Class 2 (HBL underlain by a zone of mobile water) or Class 3 (involving only an HBL) accumulations.
Assuming nearly impermeable confining boundaries, this numerical study indicates that large production rates (several MMSCFD) are attainable from both Class 2 and Class 3 deposits using conventional technology. The sensitivity analysis demonstrates the dependence of production on the well design, the production rate, the intrinsic permeability of the HBL, the initial pressure, temperature and hydrate saturation, as well as on the thickness of the water zone (Class 2). The study also demonstrates that the presence of confining boundaries is indispensable for the commercially viable production of gas from these deposits.
Interwell Pressure Testing for Field Pilots
Authors: Stegemeier George L. 
Published: December 2007

ABSTRACT
Procedures are described, and results are compared with core analyses, for a number of transient pressure experiments that were carried out between wells in a small chemical flood pilot. Tests include: (1) a standard pulse test, (2) a simultaneous pressure buildup and falloff of wells in a five-spot pattern, (3) a reverse pulse test, in which response from a producer was measured at a nearby injector during injection, and (4) production drawdown tests from normally shut-in observation wells during polymer injection and during subsequent waterflood in a nearby injector. Flowing these observation wells provided an effective way to measure in-situ mobilities of injected fluids.
For pulse tests, a simplified method for design and interpretation of single pulses is derived from basic equations. Dimensionless functions, representing directional permeability and geometrical mean permeability, are shown to be functions of a single dimensionless time lag of the maximum pressure response. For large dimensionless time lags, the ratio of dimensionless permeabilities approaches the value πe and simple geometric relationships may be used to predict either compressibility or formation thickness.
Case Histories: New Perforating Technology Enhances Workover Operations in Difficult Scenarios
Authors: Bargawi Riyadh A. , Dean Doyle , Clemens Jack , Dove Johnny 
Published: December 2007

Abstract
Wells in Saudi Arabia, onshore and offshore, often require workover because of the highly corrosive environment to which the downhole equipment is subjected. During these operations, the downhole equipment often must be repaired or replaced. To maintain well control during these workovers, a single hole often is required to allow the kill fluids to be circulated. Traditionally, these holes have had to be made with explosives and a "Soft Shot" perforator or by mechanical hole-punching methods. Workover jobs that required a single hole to be punched were often economically compromised by the delays in mobilizing explosives and because failures to perforate "soft" tubing were common when using traditional mechanical hole-punching methods.
This paper presents several case histories in which a newly developed slickline-deployed, electro-mechanical tubing punch was used for the first time worldwide. Although the workover requirements in the wells differed and were in both onshore and offshore environments, all required a single hole to be punched. The method was 100% successful and solved the problems that had been experienced using conventional methods.
Horizontal and Multilateral Drilling Technology: Contribution Towards Production Improvements of Naturally Fractured Reservoir (Case Study, Algeria)
Authors: Benzagouta Mohammed S. , Amro Mohammed M. 
Published: December 2007

Abstract
The studied oilfield is located in Algeria. The reservoir succession is subdivided in four lithological parts. Two main parts form the special focus of this study: part 1 and part 2. Results, based on permeability and porosity, show very low values, close to the standard cut off. The presence of fractures with a high frequency may have an important impact on production. These fractures have been identified by the use of the borehole image tools. These fractures are of different types: opened fractures and half opened and sealed. In their pattern, these fractures are longitudinal and transversal. Contribution of fractures towards the change in permeability and porosity shows a variable fluctuation, despite their considerable frequency. Thus and owing to the reservoir characteristics and their evolution, gathered to the fracture aspect presence and, for better efficiency, requirement for an application of advanced drilling technology is ideal. Therefore, the horizontal drilling type may remain an ultimate option. Since the target is to intersect a high number of fractures. The length of the horizontal section might not be long, and therefore high DLS might be tolerated. Productivity from horizontal wellbore can be as much as 20 times greater than from a comparable vertical well. The major reason for such improvement is that a horizontal wellbore affords much greater exposure to the producing zone. However, the drilling cost of a horizontal well will not exceed 2 to 2-1/2 times that of a vertical well. The advantage of horizontal drilling in such area will be also debated.
Intelligent Completions Technology Offers Solutions to Optimize Production and Improve Recovery in Quad–Lateral Wells in a Mature Field
Authors: Abduldayem Mohammed A , Shafiq Muhammad , Al Douhan Nader D. , Baluch Zulfiqar A. 
Published: December 2007

Abstract
This paper describes an innovative completion solution with state-of-the-art reservoir monitoring and control completion technologies that allows commingled oil production from quad laterals wells in Abqaiq field. Many intelligent completions wells have been successfully installed in Abqaiq, operated by Saudi Aramco. Included in the description are equipment selection, design and development details, installation procedures, and "lessons learned" after installation of the fully hydraulic tubing-retrievable advanced completion system with digital permanent down hole monitoring system.
Intelligent completions will allow individual lateral testing and allocation of production rates to optimize each lateral contribution and the overall commingled well rate. Along with real time monitoring, sustainability of well rate will be extended by timely reacting to any changes to reservoir and well conditions.
Using variable-position flow control valves, early water breakthrough can be delayed, to increase recovery. Monitoring the flowing pressure in real time allows producing the well at optimum rate; i.e., above bubble point pressure. Ultimately, intelligent completions will limit the water handling at the surface and concurrently increase the recovery factor in heterogeneous fractured and fissured carbonate reservoirs for MRC (Maximum Reservoir Contact) wells.
Integration of NMR with Other Open Hole Logs for Improved Porosity, Permeability and Capillary Pressure of Gas Sand Reservoirs
Authors: Hamada G. M. , Oraby M. El. , Abushanab M. A. 
Published: December 2007

Abstract
Analysis of tight gas sand reservoirs is one of the most difficult problems. Many tight formations are extremely complex, producing from multiple layers with different permeability that is often enhanced by natural fracturing. Therefore, looking for using new well logging techniques like NMR in individual bases or in combination with conventional open hole logs and building new interpretation methodology is essential to well define and obtain the representative reservoir characterizations.
Nuclear magnetic resonance (NMR) logs differ from conventional neutron, density, sonic and resistivity logs because the NMR measurements provide mainly lithology independent detailed porosity and a good evaluation hydrocarbon potential. NMR logs can be used to determine formation permeability and capillary pressure.
This paper concentrates on three petrophysical applications of NMR; 1) present a technical method for porosity calculation in which density and NMR porosities are combined and calibrated to core, 2) Use new empirical method of bulk gas volume (BG) in the invaded zone for permeability estimation termed BGMRK and 3) Use T2 distribution for capillary pressure approximation and correct pore size distribution for gas.
These applications of NMR logs have been applied in a gas sand reservoir field of different facies and permeability varies from less than 0.1 md to more than 100md related to facies changes. These applications result in a) The technique of using combined NMR and bulk density data significantly reduces uncertainty in porosity through elimination of the neutron log down to 0.5%. b) The new approach of "BGMRK" resulted in very simple facies independent model to calculate reliable permeability 2. c) Capillary pressure can be approximated from NMR T2 distribution and then the integration between cap-curves and T2 distribution can be corrected for partial pores fluid fill.
Reduced Water Production and Increased Oil Production Using Smart Completions and MPFM "Case Study"
Authors: Al-Shenqiti Mohammad S. , Dashash Alaa A. , Al-Arnaout Ibrahim H. , Al-Driweesh Saad M. , Bakhteyar Zaki 
Published: December 2007

Abstract
Saudi Aramco's drilling strategy witnessed a change in the last few years by drilling horizontal and extended reach maximum reservoir contact (MRC) wells. One of the objectives behind this strategy is to improve the well productivity by maximizing oil production and minimizing water production. The paper will demonstrate the challenges and successes of reducing produced water by using smart completions and how multiphase flow meters (MPFM) helped in getting better results to allow faster decision making. In one of the challenging areas in Ghawar field where the water will reach the wellbore much faster via the reservoir's fractures. Using the smart completion with the conventional rate testing (the plant's testing facility) required longer time to reach the best possible setting for the downhole flow control valves to achieve the optimum flow rate. Using the combination of smart completion and portable MPFM (Multiphase Flow Meter), resulted in reducing the water cut (WC) form 20% to 0% maintaining the same required average oil rate (Fig. 1), and enabled better reservoir management. The results from this experience, as will as other experiences, have been utilized in a recent major increment in the Ghawar field that was mainly developed using multilateral MRC wells equipped with downhole smart completions and surface MPFMs.
Log-Based Geomechanical Characterization and Sanding Potential Analysis on Several Wells Drilled in Southern Part of Oman
Authors: Franquet Javier A. , Stewart Gregory , Bolle Luc , Ong Seehong 
Published: December 2007

Abstract
This paper presents a methodology to analyze sanding potential on clasticreservoirs by determining the critical drawdown pressure required to on-setsand production. The critical drawdown pressures are obtained from ananalytical model that describes the mechanical stability of a perforationcavity in a Mohr-Coulomb material under Darcy flow regime. The study wasperformed on several wells from different oil fields in South Oman with themain objective to identify the formation intervals with the greatest sandingpotential.
The critical drawdown assessment requires geomechanical characterization ofthe formations of interest. Static mechanical properties and strengths wereobtained from a log-based program. This program is based on FORMEL; which is aconstitutive model describing the microscopic processes occurring in a rocksample during triaxial loading. The basic inputs for running the model are welllog information, petrophysical volumes, and the pore fluid properties of theformation. The geomechanical characterization and the pore pressure profilewere used to calculate the maximum drawdown pressure needed before sandingoccurs on foot by foot basics. A clear correlation was found between lowstrength formations and the intervals with low critical drawdown pressurevalues.
The analysis allows identification of high sanding potential intervals for aselective perforation program, and it supports gravel pack decisions whererequired. Also, the critical drawdown profiles assist to choose a suitable sandcontrol completion technique, ranging from classic gravel packing tostate-of-the-art expandable sand screen installations.

Introduction
Knowledge of rock mechanical properties is important for the planning of bothdrilling and production strategies. Traditionally, rock mechanical propertiesare obtained directly from laboratory triaxial tests on core samples. Hence, mechanical properties are typically only defined at discrete depths were thecore samples were taken and lab values can be skewed due to the core handlingprocess. Accurate sand production prediction, however, requires a continuouspresentation of mechanical properties with depth including the cohesivestrength and internal friction angle of the rock.
Successful Water Shut Off Treatment With Engineered Micro-Cement Slurry Through Coiled Tubing in Pakistan
Authors: Jamil Ainul H. Abdul , Ahmad Tofeeq 
Published: December 2007

ABSTRACT
This paper describes the success story of the first water shut off treatment using Engineered Micro-cement Slurry (EMS) through Coiled Tubing in Pakistan. The well was an oil well producing from multiple zones, but mainly the lower zone (C-Sand). Due to high water cut, it was decided to isolate the C-Sand and to produce only from the upper perforations (A/B Sands). Based on economics and technical feasibility, water shut off treatment through a cement plug was selected to isolate the C-Sand zone. 148ft of cement plug was squeezed and spotted across the C-Sand through coiled tubing using conventional cement slurry. After setting the cement plug, water cut was reduced by 23% and the well initially produced up to 380bopd from the A/B Sand. After 3 months production, water cut level increased drastically back to 100%. A slickline run confirmed that the cement plug had failed and top of cement dropped 48ft from its original depth. It was suspected that the plug failed due to possible contamination in the cement, which enabled water to channel up across the plug. A remedial cement plug through coiled tubing was subsequently set, but this time using EMS slurry to ensure that any channels in the previous plug were cemented and ensuring that the perforations were sealed off completely. The job was conducted successfully and the water cut was reduced by 25%, with initial production of 500bopd from the A/B Sands.
Subsurface Fracture Analysis in Carbonate Reservoirs: Kohat/Potwar Plateau, North Pakistan
Authors: Jadoon Ishtiaq A. K. , Bhatti Khalid M. , Siddiqui Fareed I. , Jadoon Saeed K. , Gilani Syed R. H. , Afzal Munazzah 
Published: December 2007

ABSTRACT
Carbonate reservoirs in Northern Pakistan are characterized by tight limestone. In these reservoirs, fractures are important for production and reservoir modeling. This paper addresses problems related to subsurface fracture analysis based mainly on image logs.
Natural fractures occur as systematic and unsystematic sets of definite and random orientation respectively. The subsurface analysis of fractures uses electrical and acoustic image logs to characterize fractures as either natural or induced features. They are classified as conductive or resistive features, representing possibly open or closed (mineralized) fractures, respectively. Using image logs, natural fractures are interpreted and classified descriptively to be continuous or discontinuous features representing systematic fractures or classified as chicken-wire (microfractures) fractures representing unsystematic sets. Statistical analysis of fractures is used to classify them into geometrical and genetic sets as longitudinal (extensional), transverse (tensional), and oblique (shear) to the structure. Transverse fractures are known generally as most open. They develop parallel to the maximum horizontal in-situ stress and extend deep into the structure. Longitudinal fractures, those parallel to the fold axes, are observed to produce hydrocarbons in several fields in Northern Pakistan. Fracture density impacts production and reserves calculations. However, fracture density is strongly influenced by the lithology and layer thickness. Widely spaced fractures are observed in massive carbonate reservoirs, and closely spaced fractures of narrower aperture are observed in laminated strata. Thus, individual fractures in massive carbonates require to be identified for their impact on production. Fractures are observed to occur as discontinuous features of right or left-stepping geometry and as en echelon features of significantly wider aperture in shear bands. These features together with vugs and leached features may provide zones of higher porosity, permeability, and storage capacity with isolated distribution in tight carbonates. Therefore, knowledge about fracture occurrence and distribution is important to predict sweet spots for drilling and field development.
Saudi Arabia's Master Gas System—Its Overview and the Corrosion Control Programs
Authors: Chen Edmund Y. , Al-Helal Fahad Eid 
Published: December 2007

ABSTRACT
This paper presents an overview of Saudi Arabia's Master Gas System (MGS), specifically the Phase I program. All the source gases, collected from the various fields, are associated with sour crude production. Significant potential corrosion problems arise in the handling and processing of these gases. For this reason, extensive corrosion control programs have been implemented in the very early stage of the program. In this paper, the related corrosion control measures will be discussed. Some facilities in the MGS have been in operation for more than two years. Corrosion monitoring data indicates that corrosion has been under good control.
A Laboratory Technique for Screening Shale Swelling Inhibitors
Authors: Roehl Edwin A. , Hackett James L. 
Published: December 2007

Abstract
A new technique was developed for quantitatively analyzing the effectiveness of shale swelling inhibitors in retarding fluid adsorption and volume expansion. Details of testing procedures, equipment construction, and design rationale are provided. Comparisons are made to methods commonly used in mud labs today, and examples of test results are given to illustrate the new technique's usefulness and versatility. Relevant concepts of clay hydration theory are discussed to provide background for interpreting the presented experimental results. Differentiation between crystalline swelling, and combined crystalline and osmotic swelling is achieved by applying a mechanical restraining force (preload) to shale samples while being hydrated. Mud additives examined include various salts, ferrochrome lignosulfonate, and several polymers.
Stochastic Modeling of Two-Phase Flow in Porous Media
Authors: Smith Peter J. , Brown Christopher E. 
Published: December 2007

ABSTRACT
A recurring problem in Reservoir Engineering is how the innate variability of geophysical systems can be appropriately modelled. In recently published studies variability has been introduced into the models of single phase flow by expressing them as stochastic processes. Following this development the aim of this paper is to establish the main characteristics of immiscible flow in a non-uniform porous medium represented as a stochastic process. For this purpose Monte Carlo simulation is appropriate. Both steady-state and transient (ie. displacement) systems are examined. Differences in the one and two dimensional simulation behaviour emphasise the importance of correct averaging to produce representative parameters. Direct results of this study are to the use of composite heterogeneous cores. In the longer term a basis is established for the development of reservoir engineering models formulated in a stochastic form.