bluuebunny/crossref_metadata_2025_split huggingface dataset:
Prediction of Carbonate and Sulfate Scales in Oilfields
Authors: Yeboah Y. D. , Samuah S. K. , Saeed M. R. 
Published: December 2007

Abstract
This paper presents a new and reliable scale prediction model. The available models for scale prediction are based only on thermodynamics and limited solubility data. The new model is based on thermodynamics, kinetics and hydrodynamics of the system. The model uses experimental solubility data in single and mixed-salts as well as natural oilfield brines to accurately predict scaling potentials. Once the potential has been established to exist, the model uses the flow characteristics and experimental kinetic data to predict the scale deposition profile as a function of position and time.
Critical saturation indices beyond which scaling occurs with near certainty have been established for the common scales SrSO4, CaSO4.2H2O, BaSO4 and CaCO3. The results of the model prediction in actual oilfields and test wells are presented. The model has been developed in a menu-driven, user-friendly format with options for tabular and graphic presentation of results. This paper presents details of the computational approach used to predict the saturation index or scaling potential.
Nimr Horizontal Drilling: A Case History
Authors: Al-Rawahi S. M. , Small G. P. , Glendinning D. R. 
Published: December 2007

Abstract
The recent technological advances in horizontal drilling techniques and design optimization have enabled Petroleum Development Oman (PDO) to develop a number of its fields by horizontal drain holes. More than 70 horizontal wells have been drilled and completed in the different fields within the PDO concession area (table-1). About 40% of the horizontal wells to date have been drilled in the Nimr oil field, in the Eastern Flank (Fig.1), where drilling a horizontal well today is cheaper and faster than drilling a vertical well less than three years ago.
Cost effective casing design, drilling fluid optimization and the application of improved deviation and cementing techniques have resulted in significant drilling and completion cost reduction and more efficient performance.
The increased recovery of the heavy and viscous oil, delayed water breakthrough, improved PIF (Productivity Improvement Factor), and reduced skin damage are some of the more immediate benefits. While in the long run, it is planned to replace vertical drain holes by horizontals at a ratio of more than two to one resulting in accelerated oil production and reduced surface facilities congestion. Moreover, reservoir studies have showed a potential increase in the recovery factor that should generate wider applications for horizontal wells.
This paper reviews the different steps of the horizontal well design improvement, the milestones that have been achieved in both drilling and completion techniques, the future development drilling plans of the field and the potential applications for other fields with similar geological and reservoir characteristics. It also highlights the problems that had been encountered in both the drilling and the production phases and the techniques used to overcome them.
The successful application of horizontal well technology in the Nimr field has only been possible through the multi-disciplinary efforts of Drilling Engineering, Production Chemistry and Petroleum Engineering staff.
Horizontal Drilling in Saudi Arabian Oil Fields: Case Histories
Authors: Al-Buraik K. A. , Pasnak J. M. 
Published: December 2007

ABSTRACT
A total of thirteen wells have been drilled in the carbonate reservoirs and eight wells in the sandstone reservoirs. Currently there are eight wells in progress.
These wells represent the first horizontal wells drilled in Saudi Arabia. This paper will present generalized case histories for both carbonate and sandstone horizontal wells. It will also discuss well plans, drilling fluids, casing, cementing liner, coring, logging, and completions. In addition, problems encountered during drilling will be discussed.
Application of Short-Radius Horizontal Hole Drilling
Authors: El-Sadek A. S. 
Published: December 2007

ABSTRACT
The short radius horizontal hole drilling technique is used in ADCO operations to turn the uell bore from vertical to horizontal within the target reservoir in less than 44 ft of vertical hole.
Experience gained from the drilled wells have been used to improve the drilling programme and drilling tools and which has continuously resulted in increasing the length of the horizontal hole at a reduced unit cost.
Sea Level Changes in the Aptian and Barremian (Upper Thamama) of Offshore Abu Dhabi, UAE
Authors: Azer S. R. , Toland Christopher 
Published: December 2007

ABSTRACT
The sequence stratigraphy of the Early Cretaceous (Aptian and Barremian) Upper Thamama Shuaiba and Kharaib Formations is studied using cores and logs from three key wells in Offshore Abu Dhabi. Three regressive transgressive cycles are readily recognised in the Shuaiba and Kharaib Formations. Two unconformities are fairly well documented at the top Shuaiba and at the base Kharaib. Emphasis is given to three sequences within the Shuaiba and Kharaib Formations.
Shallowing or deepening upwards cycles are determined and the relative sea level curves constructed.An attempt to correlate the produced sea level curves with the global Vail/Haq curves is carried out to verify whether these apply to the area or that there are different sea level curves pertaining specifically to Offshore Abu Dhabi.
The transgressive and highstand systems tracts, maximum flooding surfaces and sequence boundaries are determined. Chronostratigraphic zonation and correlation of the Shuaiba and Kharaib Formations are carried out to determine whether straight line layer cake stratigraphy applies, as is currently believed or whether the lithostratigraphic units are in fact diachronous. Distribution charts for major fossil groups are produced. Ammonite data for age calibration are introduced. The unconformities within the Upper Thamama are defined and confirmed.
The main objective of this project is to erect a provisional sequence stratigraphic framework for the Upper Thamama in the Offshore Abu Dhabi area.
This framework forms a template for further reservoir description and sequence stratigraphic studies.
3-D Electrofacies Model, Safaniya Reservoir, Safaniya Field, Saudi Arabia
Authors: Al-Sabti H. M. , Al-Bassam K. A. 
Published: December 2007

ABSTRACT
The Safaniya reservoir is the main producing reservoir in the Safaniya Field, the largest offshore oil field in the world. It lies within the Wasia Formation of Middle Cretaceous Albian age, and was deposited in a fluvial dominated deltaic environment. The southern part of the field is dominantly thick, massive sands, while the northern part is more heterogeneous, with all types of sub-deltaic environments; distributary channels, mouth bars, crevasse splays and interdistributary bay shales, prodelta shales, and shallow marine shales and sands. The complex heterogeneity of the reservoir provides a challenge in characterizing reservoir behavior. To better understand fluid movement; lateral water encroachment, and water fingering in the reservoir architecture context, a 3-D electrofacies model (Abbott, 1982) was constructed for the Safaniya reservoir. It is based upon a detailed 11-layer geologic description, used an electrofacies database of 573 of the 624 total wells in the field, and was built using a 3-D geocellular modeling program.
The model has an area of 3900 sq. km. The modeled vertical interval from top Mauddud to Base Dair marker averages 540 feet in thickness. Cell dimensions of the model are 250m X 250m areally and 1 foot vertically. Reservoir thickness is several hundred feet which yields a total 3-D model of 45.5 million cells.
This electrofacies model is available to generate various maps and cross sections to help in reservoir management decision making and to provide 3-D geologic input for multi-layer reservoir simulation models.
Gas Gravity Drainage Under Secondary and Tertiary Conditions in Fractured Reservoirs
Authors: Saidi A. M. , Sakthikumar S. 
Published: December 2007

ABSTRACT
Variety of gases can be used for injection into reservoirs under conditions varying from immiscibility to full miscibility. Also gas injection has found applications in both secondary and tertiary conditions. The advantage and disadvantage of different combinations of each of the above will depend on the particular context. The reported laboratory work and subsequent simulation work has been done in clarifying the influence of the parameters controling the efficiency of the different processes under gravity drainage conditions.
This paper addresses the problem of oil recovery by gas injection under primary condition and of water flooded reservoirs with particular emphasis on the use of lean hydrocarbons gas. A systematic investigation was carried out to highlight the parameters controling such processes. The work comprised of analysing reported laboratory experiments under reservoir conditions and interpretation of these experiments using a compositional simulator. Laboratory experiments included both centrifuge tests and core floods under reservoir conditions. The core displacement was designed to help determine the 3- phase oil relative permeability at low oil saturation.
The investigation confirms that tertiary lean gas injection is capable of mobilizing Waterflood residual oil and thus reducing the residual oil saturation. The work also helps to identify the role of 3- phase relative permeability. In addition the role of gas-oil diffusion under tertiary condition is discussed. Moreover, simulations were made to clarify the effect of block boundaries in block-to-block interaction.
Application and Optimization of Continuous Flow Gas-Lift Wells for Zeit Bay and Ras Budran Wells
Authors: El Massry Y. A. W. , Abdel Hamid A. H. , Abu El Yazid M. M. 
Published: December 2007

ABSTRACT
Gas lift installation in the Ras Budran and Zeit Bay fields have been tailoredto fit the widely differing both reservoir conditions encountered. The accuracy of multi-phase flow calculations combined with well test information and their usein simulating well performance has played an important role in efforts to improvegas lift efficiency in both fields.
Using these well performance simulatedmodels, an analytical procedure has been introduced to determine the optimum distribution of gas to wells in a continuous flow gas lift system by which wells can belifted over a range of producing conditions by regulating the injected gas volumesat surface.This procedure has been utilized in the assessment of the requirement for future gas lift gas compression and non-associated gas supply wells.
It is demonstrated throughout this paper that potential exists in many areas for increasing production by the optimization of lift gas resources through application of sound engineering and operating principles.
Development and Use of a Finely Gridded Window Model for a Reservoir Containing Super Permeable Channels
Authors: Valle Antonio , Pham Anthony , Hsueh P. T. , Faulhaber John 
Published: December 2007

ABSTRACT
This paper discusses the development and use of a finely-gridded 3-D window model (1/3 km by 1/3 km by 15 layers) for a highly heterogeneous producing area of a large carbonate reservoir. The reservoir portion being modeled contains a vast area of hardened dolomite rock interbedded with a leached Cladocoroosis facies. This leached Cladocoropsis facies forms inter- connected linear vugs in the rock yielding horizontal permeabilities in the tens of darcies. The vertical permeability across the dolomite, however, is in the microdarcy range.
Special consideration was given to model layer selection, horizontal and vertical permeability distribution, grid size, and relative permeability assignments in order to accurately model the observed field performance. The results of this finely-gridded window model compare well to observed historical field data and are superior to results of previous coarser models. The model is being used to identify areas of poor oil displacement for possible exploitation and increased oil recovery.
Drilling Templates for Drilling Before Offshore Installation
Authors: Ghany M. M. Abdel , El Ahmady H. M. 
Published: December 2007

ABSTRACT
Drilling template is a simple plane steel structure fabricated using heavy wall pipes and beam elements. It acts as a guide frame for designated drilling wells and as a guide for the installation of jacket positioning by the docking piles. Templates could be set either on the sea-bed or around an existing well by using hanging clamps.
Drilling templates have been widely used in offshore activities when drilling operation is preceeding platforms installation. Such case usually exists in new development plans where drilling new wells and construction of production facilities are interfering with each other. Templates, then could be used for drilling wells while project is proceeding its normal schedule.
In many other cases templates are used to drill and evaluate the wells first and based on the results, proper sizing for production equipment and facilities will be followed.
AGIBA had successfully constructed and installed three drilling templates for the developing project of its ASH- RAFI Lease. ASHRAFI DEVELOPMENT LEASE was awarded to AGIBA in Sep., 90. The development plan of this new offshore concession placed the drilling campaign in between the whole project schedule. In order to execute the work of both Drilling & Project Departments without waiting each other, the idea of drilling template was implemented to avoid any conflict between the execution dates.
This paper will discuss AGIBA's experience in the installation of its three templates in ASH- RAFI. Planning for the job, preparation of the existing wells, installation, positioning and orientation. We believe these procedures will positively assist in future similar jobs in offshore operations.
Applications of Projection Onto Convex Sets to Stochastic Inversion
Authors: Malinverno Alberto , Rossi D. J. 
Published: December 2007

Abstract
Obtaining a map of the spatial distribution of some physical property in a reservoir from sparse data is a fundamental problem in reservoir characterization. This problem can be stated in terms of an inverse problem as the search for a map that satisfies certain constraints. The constraints are a set of measurements and information on the spatial statistics of the property. A common practice is to construct nonunique "conditional simulations," i.e., maps that are consistent with point measurements (typically obtained at wellbores) and with the spatial statistics of the property being mapped. We introduce a method (Projection onto Convex Sets, or POCS) that lets us perform a "stochastic inversion," i.e., obtain nonunique simulations that are constrained not only by spatial statistics and point measurements, but also by low-resolution measurements obtained away from the wellbores (e.g., seismic traveltime data). Numerical experiments show that incorporating data from the region away from wellbores allows us to better locate large-scale heterogeneities in the reservoir volume. Locating heterogeneities may be important for accurate modeling of fluid flow within the reservoir.
MWD Rock Mechanical Properties to Avoid Drilling Related Problems
Authors: Ahmed U. , Bordelon D. , Allen D. 
Published: December 2007

Abstract
Borehole instability, wellbore sloughing and lost circulation are some of the drilling-related problems that can be avoided with real-time access to mechanical properties of the rock and certain failure geometry. Typically, mechanical properties of the rock are available after the completion of drilling or from a nearby well. Neither cases allow one to make real-time drilling changes to the current well to avoid any of the above drilling-related problems. Derivation of rock mechanical properties and failure geometry from MWD (measurement while drilling) have been the subject of research in recent past; however, the complex nature of the problem continues to elude the industry.
In this paper we document two recent developments in calculating rock mechanical properties and failure geometry through use of MWD tool responses. First, we discuss the combined use of drilling weight-on-bit (DWOB), torque (TOR) and rate of penetration (ROP) to establish rock failure characteristics of the wellbore wall. We follow this with a note on the integration of MWD data with LWD (logging while drilling) data such as gamma ray and dual resistivity to identity rock via lithology and strength parameters and to determine the susceptibility of the rock to failure. Second, we illustrate the integration of MWD caliper measurements with wireline measurements to establish criteria for failure geometry prediction and calculation on a real-time basis. Several field examples are presented to illustrate the developments and findings reported.
Casing System Risk Analysis Using Structural Reliability
Authors: Adams A. J. , Parfitt S. H. L. , Reeves T. B. , Thorogood J. L. 
Published: December 2007

Abstract
This paper describes a method for quantitative risk analysis (QRA) of casing/tubing systems, using a structural reliability approach. The technique was used to calculate risk-calibrated design factors for exploration and development wells, taking into account the nature and consequences of failure for each string, stress check type and load case. The methodology and results are a significant advance on previous work.
The Aftermath of the Kuwaiti Oil Fires
Authors: Bou-Yabes A. A. , Akbar S. H. 
Published: December 2007

Abstract
Although the last oil well fire was announced dead officially on 6th November 1992, the oil wells were far away from being ready to be put back on stream for oil production which is the main source of income for a war-torn country. This paper presents more accurate statistics of the Fire Fighting Stage and discusses in detail the efforts, techniques, equipment, procedures and steps taken to restore the production from the explosions and fire damaged wells. Figure 1 shows a pie chart for the condition of the wells controlled by the major fire fighting teams, while figure 2 shows the pie charts for the methods used by these teams in controlling the oil wells. The operations executed under the Post Capping Operations, although does not seem as dangerous as the initial Capping of the wells, it is equally as hard and demanding as the initial Capping Operational is almost equivalent to capping the gushing wells. It was not important as to how you cap the well during the fire stage. However, during post capping operations you have to stick to the laid out procedure using the required available equipment to achieve a set goal of having the wells ready to be taken for the rig workover. To achieve this ultimate goal of installing a new wellhead and X-mas tree instead of the Damaged remains of the wellhead, the following steps were developed in what is known as the Post Capping Operation:-
Cutting off the damaged wellhead and securing the well with full bore ball valves. Fishing the tubing string to allow for working space. Securing the well with inflatable packers. Installing a new wellhead.
The above work is not as simple as it may seem, as most of the wells were full of bad surprises.
Strategic Background and Economic Analysis in the Development of a Project for Coiled Tubing Drilling
Authors: Cameron Gerald , Ozzola Vito , Schenato Adelmo 
Published: December 2007

Abstract
As operating costs escalate and the oil price remaining stubbornly low, now more than at any time in the history of the oil industry the economics of every phase of business must be minutely examined from the exploration and appraisal through to production. In addition to this, another problem arises when dealing with a project such as coiled tubing drilling, as whilst this technology will provide a similar end product to conventional drilling practices it is such a departure from conventional drilling practices as to create scepticism.
This paper describes some of the ground work involved as part of a feasibility study carried out for coiled tubing drilling for a situation of drilling from top hole to total depth and sets out a system whereby the financial implications of investment into a new technology can be assessed by comparing three strategies. The best scenario for return on investment and increased profitability can then be chosen.
The study deals with the economic analysis, risk analysis and the methodology used in achieving the final results. These results compare the three strategies on the basis of numerical values of drilling operational costs and production.
Diamond-Enhanced Insert: New Compositions and Shapes for Drilling Soft-to-Hard Formations
Authors: Keshavan M. K. , Siracki M. A. , Russell M. E. 
Published: December 2007

Abstract
Increased penetration rates, accompanied by longer bit life, have always been primary objectives of both rock bit manufacturers and drilling contractors. Diamond-enhanced tungsten carbide inserts have been employed successfully in the gage row of soft formation three-cone rock bits. However, the current semi-round top geometry used in the manufacture of diamond-enhanced inserts has limitations. Two such limitations are slower penetration rates when replacing chisel-type gage inserts in certain soft formations and premature breakage in medium-to-hard formations (IADC 6-2-7 to 7-3-7 type drilling). This paper reviews recent progress in the development of tougher diamond-enhanced inserts and new geometries, such as the inclined chisel gage inserts.
Laboratory test results are compared between the new, tougher enhanced inserts, the standard enhanced inserts and the standard tungsten carbide grades. Successful field tests of diamond-enhanced heel inserts used in medium-to-hard formations will be reviewed. The impact on bit life, penetration rates and drilling costs of the new enhanced insert composition and geometry technology also will be discussed.