bluuebunny/crossref_metadata_2025 huggingface dataset:
Cossack Development – First Oil for Woodside
Authors: Seymour E. V.
Published: December 2007

The Cossack oilfield will be Woodside's first "oil" development The Cossack #1 discovery well was drilled in January 1990, and encountered a gross oil column of 54 m. Recoverable reserves are estimated to be 60 million bbl "expectation" and 30 million bbl "proven". Screening studies of a number of development alternatives were quickly completed In April 1990. These studies were followed by more detailed feasibility studies, concluded in September 1990, which confirmed that the field was ideal for a standalone development A project team was formed and project definition studies completed in January 1991, ultimately leading to full budget approval in July 1991. First oil is scheduled for June 1993, three and a half years from the date of the discovery well. It is planned to recover the oil by means of up to six subsea wells, drilled in a cluster and tied back to a Floating Production, Storage and Offloading (FPSO) vessel. This will be a converted 155,000 dwt tanker which will be moored via a disconnectable system, thus being able to steam out of the path of tropical cyclones which regularly pass through the area.
Evaluation of Steam-Injection Designs for the Duri Steamflood Project
Authors: Fuaadi I. M. , Pearce J. C. , Gael B. T.
Published: December 2007

The Duri Steamflood (DSF) Project is the largest thermal enhanced oil recovery (EOR) project in the world, surpassing in production both Kern River and Belridge in the San Joaquin Valley of California. The field is located in Riau Province on the island of Sumatra, in Indonesia. Duri is the second largest field in the country, producing nearly 200,000 BOPD of steamflood production. The field is being operated and developed by P.T. Caltex Pacific Indonesia (CPI), a production sharing contractor to Pertamina.

The DSF Project will develop about 15,000 acres of reservoir utilizing over 4000 producing wells. At present, only about 1/3 of the field is under active steamflood. The DSF Project is divided into twelve development units called Areas. New Areas are about 1400 acres in size and are developed, that is drilled and put on injection, every 1 3/4 to two years.

The steamflood development involves the use of symmetric patterns of varying size and configuration. Inverted seven spots, approximately 11 5/8 acres in size, have been the *References and figures at end of paper principal pattern configuration for Area development thus far, including the Area currently being drilled [1]*. For future Areas, inverted five and nine spots, approximately 15 1/2 acres in size, are planned. This change will be implemented as a result of detailed reservoir simulation studies conducted in CPI [2].

Pattern producer completions are either cased hole gravel packs (CHGP) or, more commonly, open hole gravel packs (OHGP). Most OHGP wells have 10 3/4" casing set at the top of the drive zone, hole opened to 14", and packed with 20-40 US mesh gravel outside of 6 5/8" screen liners. Up to four distinct sand intervals and 250 ft of pay are simultaneously completed and flooded in a single pattern.

The main challenges in downhole design and completion of DSF's steam injection wells have arisen from the relatively large pattern sizes and the need to distribute high rates of steam to multiple intervals of varying permeability. Several different, multi-point, downhole injection systems have been used in Duri.

The design, field testing, and evaluation of these various systems are here presented and discussed.
Improved Productivity Through Automation of Data Gathering Activities on Offshore Platforms
Authors: Wong S. W. , Muhamad Jasni
Published: December 2007

This paper describes a project implemented by Esso Production Malaysia Incorporated (EPMI) to improve the efficiency and effectiveness of the data gathering and reporting activities on offshore platforms.

The Platform Data Capture project (PDCAP) will automate data gathering, transfer, processing and reporting of production and operation data from offshore platforms. The implementation of the PDCAP project will allow EPMI to capture production and operation data on offshore platforms using existing computing technology in combination with hand-held data entry terminals, personal computers and data acquisition mini-computers.

The PDCAP project demonstrates the use of computing technology to reduce time spent by offshore staff on routine manual tasks of data gathering and reporting. This results in increased time for the staff to perform the more important facility surveillance and trouble-shooting work which then translates to safer and more effective platform operations.
Waterflood Performance Of A Shallow Channel Sandstone Reservoir Burkett Pool, Coleman County, Texas
Authors: Patton E.N.
Published: December 2007

American Institute of Mining, Metallurgical, and Petroleum Engineers, Inc.

Discussion of this paper is invited. Three copies of any discussion should be sent to the Society of Petroleum Engineers office. Such discussion may be presented at the above meeting and, with the paper, may be considered for publication in one of the two SPE magazines.

A summary of performance and development through primary and secondary oil recovery phases of a shallow channel sandstone phases of a shallow channel sandstone reservoir of Permian age is presented. Discussion will concentrate on Amerada Petroleum Corporation's leases in the Petroleum Corporation's leases in the Burkett pool, Coleman County, Texas.

Very few early records are available; however, the discovery well was apparently drilled in 1924. Development was rapid on about 3 to 4 acre spacing. Practically all of the geologic information available is from drillers' logs. The reservoir is found at a depth of about 390 ft.

Water injection began in 1947 when produced water was injected into the pay produced water was injected into the pay section of two wells. In 1958 full scale waterflood operations were initiated. Primary recovery amounted to 22.4 per cent Primary recovery amounted to 22.4 per cent of the 11 million bbl oil originally in place while secondary recovery to June 1, 1968, was 12.3 per cent. A remaining 4.1 per cent is expected to be recovered under current operations even though the field has been producing at water cuts above 97 per cent producing at water cuts above 97 per cent for two years. Out of 209 wells drilled, 54 are currently producing a total of approximately 325 BOPD and 12,500 BWPD. Twenty-five wells are being used for injection amounting to about 14,000 BWPD.

It will be shown that a lack of data, haphazard spacing, and difficult well completions can be overcome to initiate a successful waterflood.

Introduction

The Burkett pool is located in northeast Coleman County, Texas, approximately 6 miles southwest of Cross Plains, Texas, and 45 miles southeast of Abilene, Texas, and is officially listed by the Railroad Commission of Texas as the Coleman County Regular field. This paper will present data solely from Amerada Petroleum Corporation's J. W. Harris, J. W. Harris "A", and W. T. Burns leases, which comprise about 80 per cent of the Burkett pool.

The purpose of this paper is to review the performance and development through primary and secondary oil recovery phases primary and secondary oil recovery phases of a shallow channel sandstone reservoir. Also data will be presented to support the fact that in an old pool, where unfavorable well conditions exist and much data is missing, waterflood operations can be successfully conducted.
Onshore Satellite Communications – Present and Planned
Authors: Pratt B. S.
Published: December 2007

This paper describes recent and planned developments in satellite technology which can be used to provide reliable communications to ships and other vessels operating offshore.
Technical Considerations In The Design For Project Bronco
Authors: Lombard David B. , Bray Bruce G. , Sohns Harold W.
Published: December 2007

Project Bronco has been proposed as an experiment to determine whether nuclear explosions can be used in the recovery of oil from deep oil shale deposits. The experimental objectives of Bronco are: to evaluate the overall feasibility of nuclear breaking followed by in situ retorting; to investigate the gross physical effects of a nuclear explosion in oil shale; and to assess the role of radioactivities in the production of oil by in situ retorting.

A proposed experimental site in the Piceance Creek Basin of Northwestern Colorado is described. Plans for site preparation and for emplacement and detonation of the explosive preparation and for emplacement and detonation of the explosive are discussed, as are studies to be made of the underground heat and radioactivity, of the geometry of the nuclear chimney, and of the fracturing of the oil shale. Preliminary plans for oil recovery from the nuclear chimney are reviewed.

Before this application of underground nuclear explosions can become commercially feasible, a variety of technical problems must be examined. Some of these are related to nuclear explosion effects, others to the recovery of oil from the broken rock. Consideration of these factors is followed by a discussion of some long-range technical aspects for the development of a commercial technology.
The Effect Of Asphaltic Materials On The Viscosity And Non-Newtonian Behavior Of Crude Oil
Authors: Witherspoon P.A. , Datta P. , Nagy G.
Published: December 2007

Publication Rights Reserved

This paper is to be presented at the 32nd Annual California Regional Meeting of the Society of Petroleum Engineers of the American Institute of Mining, Metallurgical and Petroleum Engineers in Bakersfield, November 2–3, 1961, and is considered the property of the Society of Petroleum Engineers Permission to publish is hereby restricted to an abstract of not more than 300 words, with no illustrations, unless the paper is specifically released to the press by the Editor of the Journal of Petroleum Technology or the Executive Secretary. Such an abstract should contain conspicuous acknowledgment of where and by whom the paper is presented. Publication elsewhere after publication in Journal of Petroleum Technology is granted on request, provided proper credit is given that publication and original presentation of the paper.

Discussion of this paper is invited. Three copies of any discussion should be sent to the Society of Petroleum Engineers office, and no Discussion should exceed ten percent of the manuscript which it discusses. Such discussions may be presented at the above meeting and be considered for publication in Journal of Petroleum Technology with the paper.

Asphaltic materials play a very important role in controlling the viscous behavior of crude oil. This has been revealed by a series of rheological studies on five California crude oils ranging in gravity from 150 to 250 API. The asphaltene contents of these oils range from 4% to 21% by weight. Detailed measurements of viscosity have been carried out at atmospheric pressure at temperatures ranging from 250 to 60 deg. C (77 deg. to 140 deg. F) using a Ferranti cone-plate viscometer. Oil viscosities have been studied at shear rates to 2000 sec.

Although crude oils are generally considered to be Newtonian fluids, the asphaltic oils of this investigation exhibit pronounced pseudoplastic, non-Newtonian behavior.
Simulation of a Highly Deviated Well in a Naturally Fractured Reservoir, Lake Maracaibo, Venezuela
Authors: Sanchez N. , Marín A. , Rattia A.
Published: December 2007

A dual porosity simulator was used to evaluate the feasibility of drilling high angle slant wells in the naturally fractured cretaceous reservoir VLA-515, which is located in a geologically complex zone constituted by interconnected fractures where the risk and drilling costs are considerably high.

Simulations were conducted to reproduce the existing reservoir conditions, and predictions were made to compare the performance of stimulated vertical wells with horizontal, and slant wells.

The production potential predicted for the slant well was twice higher than the achieved by the vertical well, in addition of increasing the oil recovery by 3 %.

Simulation results showed that the slant well will recover aproximately 9 MMSTBO during the first 5 years, while the vertical well requires 11 years to obtain the same cumulative production.

Finally, under the conditions of the VLA-515 cretaceous reservoir a 55 degrees slant well will achieve higher recovery than an horizontal and stimulated vertical wells, due to higher amount of contacted fractures as consecuence of its penetration angle into the reservoir.
Screening and Economic Criteria for Horizontal Well Technology
Authors: Crouse P.
Published: December 2007

Horizontal drilling technology has become an economic reality, and the result has been a dramatic upsurge in the number of horizontal wells drilled. As the industry's experience of drilling, completing, and producing horizontal wells increases, so does the realization that horizontal technology is not always a solution to the problem of more cost-effective production. When evaluating the potential benefits of completing wells horizontally in a specific reservoir, the performance of the reservoir as well as the economics of drilling and completing the wells must be examined.

No matter why a horizontal well is drilled, the decision to drill must come from results that analyze all reservoir data available. Technical successes and economic failures already associated with horizontal wells over the last three years have brought home this point.
Evaluation of Cuttings Transport in Horizontal and Near Horizontal Wells - A Dimensionless Approach
Authors: Martins A. L. , Santana C. Costapinto
Published: December 2007

A mechanistic model is presented to describe the stratified flow of solid-non newtonian fluid mixtures in horizontal and near horizontal eccentric annulli. The model consists of a two layer configuration, the top layer being a heterogeneous suspension and the bottom one a compacted bed of solids. It is based on conservation laws of mass and linear momentum as well as on constitutive relations which describe the interactions between the phases and between each phase and the walls. The model is applied to the several flow patterns that characterize the solid-liquid horizontal flows.

The use of the Lockhart-Martinelli dimensionless parameter, modified for solid-liquid flows, permits a concise evaluation of the cuttings transport phenomena. Dependent variables, such as solids volumetric concentration, bed height and annular friction losses, can be predicted by estimating the modified Lockhart-Martinelli parameter and the flow regime of the upper layer.
Directional Drilling Expert System
Authors: Martinez E.
Published: December 2007

Minimizing the cost of drilling a directional well is a major concern for the drilling engineer. This computerized system was developed in order to provide the drilling engineer with an advisory tool which recommends changes in the Bottom Hole Assemblies (BHA). This results in better accuracy and faster decision making; hence, considerable savings in time and money.

The system involves five integrated modules:

– A knowledge base where all the expertise concerning the subject is stored. – A database with information from the BHAs used in drilling of previous directional wells and their statistical behavior. – A database with information from the theoretical behavior of BHAs commonly used in directional drilling. – A database with information from directional surveys performed over the path of the bore hole. – Computerized applications developed to calculate and plot the path of the bore hole.

This system was developed using an expert systems technology, including a knowledge base and a inference engine. The computerized applications for plotting and calculating the course were developed in a conventional way using BASIC and PASCAL: Databases were all developed in a relational model.
Drilling Hard and Abrasive Formations with PDC Bits
Authors: Vargas J. E.
Published: December 2007

Due to the success obtained by PDC bits drilling unconsolidated formations of Miocene age several designs have been tested in an attempt to extend the PDC bit application range to the harder an more abrasive formations of Ceuta field, in western Venezuela.

Satisfactory results were obtained drilling the coper section of Mi soa formation of Eocene age when compared to the previous runs using conventional tri cone bits.

These promising results, motivated the search for a better bit design to improve drilling in hard and very abrasive formations deeper in the well.

The efforts of Research Departments of main PDC manufacturers are focused toward designing a more resistant cutter to temperature and more appropriate bit profile to reduce bit whirl•.
Determination of Design Temperature for Cement Slurries
Authors: Zacarias D.
Published: December 2007

One of the most important parameters to obtain for the appropiate cement slurry is the bottom-hole temperature which will determine the type and amount of additives needed in the slurry to achieve the required properties. At present, a new technique has been developed to determine the bottom hole circulating temperature based on data gathered with electronical tools.

Field application has produced very reliable data that one can use to calculate the required BHCT that a cement slurry will encounter.

With the application of this technology the slurry designs have been improved, and the costs have been reduced to about 27% for the production liners and 38% for the production casings.
100% Oil Liquid Phase Drilling Fluids for Deep Wells
Authors: Larreal E. , Bandeira A. , Pérez M. A.
Published: December 2007

The Colon Formation Shale (Southern area of Lake Maracaibo) and The Carapita Formation Shales (Northern area of Monagas) have been frequently drilled with invert emulsion oil base mud (IEOM) for shale inhibition purposes. However, this fluid is not the most desirable for use in drilling the Cretaceous and Oligocene productive Formation since the IEOM requires high concentrations of surfactant emulsifiers which have proven to be damaging to the pay zone.

The problem described above led to the search for a mud system formulated with 100% Oil continuos phase. It was required that this system be stable to high temperatures; have no interaction with the shale cores taken from the Colon and Carapita formations; and be formulated without strong emulsifiers.

The first part of the research was carried out in the laboratory where many formulations were tested to very high temperatures and under contaminated conditions. Return permeability tests were also run to ensure that the system would minimize formation damage. The 100% Oil mud formulation from the laboratory was then used in the Southern area of Lake Maracaibo on the well SLB-4 and in the Northern area of Monagas on the well BOQ-8. Excellent results were achieved on the trial wells in both areas and improved production rates obtained on well SLB-4 compared to other wells in the field which were drilled with standard IEOM.
The Determination of Polarity for Crude Oil Demulsification
Authors: Brüning I. M. De Andrade
Published: December 2007

A demulsifier to be effective in breaking a water-in-oil emulsion has to possess higher polarity than that of the crude oil natural surfactants. In spite of the polarity of those natural surfactants has never been measured, this general rule guided the use of chemicals in oil treatment along the years of the petroleum industry. Previous work developed a method to measure oil polarity, which proved that crude oils differ widely in their polarities. Present work extends this method to evaluate the polarity of several commercially available chemicals for crude oil demulsification. Because asphaltenes are considered to play a decisive role in emulsion stability, their polarity was also determined. The results provided an overall comprehension about the polarities involved in crude oil demulsification.
Physical Aspects of Formation Damage in Linear Flooding Experiments
Authors: Eleri O. O. , Ursin J-R.
Published: December 2007

The infiltration of fine particles into the reservoir and the resulting production decline has long been a problem to the petroleum industry. It is also generally accepted that formation damage due to particle plugging is not thoroughly understood. In contributing to the solution of this problem, an experimental study of more than 17 core plugs involving 25 linear runs has been conducted. The purpose was to study the different physical and mechanical aspects of the processes leading to formation damage caused by movement and entrapment of suspended particles (when chemical and other forces are minimized).

Permeability is a key parameter among several others that control reservoir performance. The experiments are based on the results of permeability decline in linear core tests.

Two methods of flood tests; constant flow rate and constant pressure drop, were used on Berea sandstone. Plastic particles were injected with ultra pure water as the transport medium. Essential filtercake properties required for the decline rate calculations were obtained.

Finally, particle characterization using the Coulter counter was analysed. The results combined with that of the filtercake properties were used to determine the mechanisms and extent of plugging.
Practical Considerations of Drillstem Test Interpretation of Damaged Formations
Authors: Longfield D. C.
Published: December 2007

Drill stem tests (DST's) often provide unexpected or incongruous results when compared with data obtained from electric well logs, samples, and/or cores. Commonly, DST recoveries from damaged productive zones consist of a combination of gas at low producing rates, oil or gas cut drilling mud, or mud filtrate water. In many cases, DST's such as these have only investigated the reservoir in the ncar-wcllbore area, in which the relative permeability to the productive in situ reservoir fluid has been altered due to the invasion of drilling fluids. Frequently, the damage has been so extensive that the true formation capability, relative to the productive in situ reservoir fluid at initial conditions, has not been either investigated or evaluated.

Many service company and evaluations engineers interpret DST's as described above to represent either productive wet zones, or zones with at best "average", or more often, "relatively low" permeability. When the DST has only investigated the damaged, or invaded zone, such interpretations are correct, but only with respect to the relative permeability of the altered reservoir to the produced fluid. In most cases, this will understate the relative permeability to the in situ reservoir fluid. Often, the buildup portion of the DST is dominated by wellbore storage effects, and no evaluation of permeability, especially to the in situ productive fluid, can or should be made.

Included in this paper are three case histories from Western Canada which demonstrate the importance of recognizing the impact of invasion on DST results and interpretation.
A Case Study for the Matrix Stimulation of a Horizontal Well
Authors: Frick T. P. , Economides M. J.
Published: December 2007

In previous publications we have introduced methods for the matrix stimulation of horizontal wells, damage characterization and removal, and economic criteria for the evaluation of the job effectiveness. The characteristic shape of damage, which is neither radial nor evenly distributed along a horizontal well, would impact the effectiveness of a matrix stimulation treatment. Full removal of damage is probably never practical because of thief zones and a marked inability to divert the stimulation fluids. Also, the large volume of acid to be injected in horizontal wells will likely create significant corrosion problems. Therefore, partial stimulation and perhaps partial completion, by deliberately leaving segments of the horizontal well unperforated, should be contem-plated. By balancing the expected well performance against the fluid volumetric coverage and the length of the open segments, the optimum stimulation and completion design can be evaluated. The net present value (NPV) is used as the optimization criterion.

In this paper a case study of a 1600-ft horizontal well in a 160-acre drainage area in a sandstone reservoir is presented. Based on expressions for original and posttreatment skin effects, which are presented in explicit form, an economic evaluation of several stimulation and completion design options is carried out. A general recommendation on the proper matrix stimulation in horizontal wells is derived based on the results of this case study.
A New Technique for the Evaluation of Acid Additive Packages
Authors: Houchin L. R. , Foxenburg W. E. , Usie M. J. , Zhao Jun
Published: December 2007

The expanded use of sandstone matrix acidizing techniques may have been the most significant trend of the turbulent 1980's. Gulf Coast operators have found that remedial acid treatments cost a fraction of that required for a comparable offshore completion. Improved design and application techniques now provide economic success rates greater than 80% with most treatments paying out in less than 30 days. However, one area that continues to frustrate designers of acid treatments is the unpredictability of crude oil reservoirs. Current testing procedures are inadequate, failing to accurately replicate the interaction between the treating fluid and acid sensitive crudes. Reliance on these procedures can produce catastrophic facility upsets, downhole emulsion blocks, reduced damage removal efficiency or result in a marginal treatment response.

A new simplified laboratory testing procedure was developed which more accurately simulates treatment effects under reservoir conditions. This laboratory test demonstrates the need for less reliance on surfactant non-emulsifiers and an expanded use of mutual solvents. Field data confirms more accurate prediction of add compatibility. In addition, acid treatments designed utilizing this laboratory procedure showed greater initial production response and maintained the incremental increase for a much longer time. Design guidelines are presented which address concerns of mutual solvent/corrosion inhibitor incompatibility, high temperature applications and treating volume requirements.
Mechanisms of Stress-Induced Wellbore Damage
Authors: Dusseault M. B. , Gray K. E.
Published: December 2007

In this article we discuss mechanisms of stress-induced wellbore damage, concentrating on the drilling phase. Damage is usually considered to be negative; we argue that yield and mechanical damage are often positive factors in stabilizing boreholes and in enhancing permeability. Various behavioral models for rock under different situations are discussed, and conceptual models of damage and stresses around boreholes are presented. Finally, we discuss briefly issues of borehole stability in high stress fields during production, with respect to solids production management.
Two Double Azimuth-Double "S"-Shaped Wells Planned and Drilled Using Torque and Drag Modeling
Authors: Wilson T. P. , Yalcin Oguz
Published: December 2007

Two unique double azimuth - double "S" shaped wells were recently planned and drilled in Conoco's Eugene Island Block 208 in the Gulf of Mexico.

El 208 J-4 S/T was drilled with a 25° "S" shaped top hole section which dropped back to vertical at 6,800′, then underwent a 60° azimuth change and built inclination to 32° and 48° then dropped to 12° in an "S" shaped lower hole section to TD at 12,860′.

El 208 J—5 was drilled with a 45° "S" shaped top hole section which dropped back to vertical at 7,670′, then underwent a 92° azimuth change and built to 36° in the lower hole section to TD at 11,286′.

Both wells were drilled with water based mud, steel drill pipe and conventional rotary drive, and completed as gravel packed duals.

This paper discusses how the wells were planned, drilled, and completed.

Torque and drag models were:

used extensively to plan the wellpath; updated during drilling with the actual surveys, then projected to TD to insure the drillability of the well; and used to design the drillstrings, casing, and completion tubular s.

The second well was drilled 45% faster and for 37% less cost than the first well. This was due to the optimization of the second wellplan and drilling practices.
How to Understand a Rig Hydraulic System and Use It Effectively
Authors: Wardlaw H.W.R.
Published: December 2007

No hydraulic system, however large, can be effective unless it ensures delivery of sufficient horsepower at the bit, where it can perform useful work. perform useful work. A numerical relationship is developed and computer plots presented, showing the critical dependence of bit hydraulic horsepower on pump operating pressure for selected combinations of variables.

The need for raising pressures is indicated for deeper wells, where the bit is remote from its source of hydraulic supply. Other factors shown to be of prime importance in determining pressures levels are pipe size, mud density and hole size.

The choice of nozzle diameter combination is less critical than is often supposed. A simple method of choice., due to Goins, is discussed and recommended. With this method, choice virtually depends only upon hole size and pump operating pressure, and the selection remains unchanged until one or another of these criteria is changed. Validity can be readily checked at the rig. A simple tabulation is available to the driller or the tool pusher. Results are proven to be within 96 to 100 percent of absolute optimum. percent of absolute optimum

Introduction

A hydraulic system in a rotary drilling rig is relatively wasteful of power. For example, it would not be unusual for a pump receiving mechanical energy at the rate of 1,000 hp to deliver not more than 750 hp to the hydraulic system, of which only about 400 hp is actually being used in hydraulic jetting action at the bit.

If such a system, normally wasteful of power, is also operated inefficiently and power, is also operated inefficiently and without proper engineering foresight, it would not be surprising to find the bit action starved of hydraulic power, and the drilling capabilities of the rig seriously curtailed.

This paper will examine the important factors controlling efficiency of the rig hydraulic system, and indicate how these factors should be adjusted to provide reasonably high efficiency with a reasonable economy of engineering effort.

Survey of the System

Fig. 1 shows the rig hydraulic system in diagrammatic form.

Trans
Increasing Extended-Reach Capabilities Through Wellbore Profile Optimization
Authors: Banks S. M. , Hogg T. W. , Thorogood J. L.
Published: December 2007

While some extended reach wells appear to be drilled with comparative ease, others to deeper targets and lower departures can present all sorts of difficulties. A simple two dimensional model is presented specifically to illustrate the interaction between the key variables associated with an extended reach well: kick-off point, locked-in inclination, build-up rate and tortuousity.

The analysis indicates that the maximum achievable drillable depth depends upon inclination and has a minimum in the region of 45-55 degrees. Maximum reach may be obtained by, wherever possible, adjusting the kick-off depth to achieve a locked-in inclination of 70-75 degrees. Drillable depth is not very sensitive to initial build-up rate. Excessive tortuousity can severely limit drillable depth and should therefore be used as an objective measure of directional drilling contractor performance.
Drilling Contractor Selection: A New Approach Evaluates the Quality of the Contractor
Authors: Boyle J. E. , Turnbull J. B.
Published: December 2007

The paper describes a new approach to Drilling Contractor selection. The objective of this approach is to take into account the human element that significantly influences operational performance. Cost savings can be realised if loss of performance through minimising the learning curve can be achieved.

The evaluation focusses on the intangible factors of the contractor. Primarily reviewing the calibre and experience of his personnel, as quality people are considered key to good performance. Once the cost for the intangible factors has been estimated it is added to the tangible cost to give an overall effective cost. The contract is then awarded on the basis of the lowest overall effective cost.
Optimization of the Drilling Performance in the 17½-in. Section of an Exploration Well in the Overthrust of Southern Italy
Authors: Besson Alain , Toutain Patrick , Scott D. E. , Meany N. C.
Published: December 2007

The overthrust area of southern Italy presents a difficult drilling environment. The terrain is mountainous, the formations are tilted, abrasive, and lost circulation can be anticipated. The formations encountered in the 17-1/2″ section of an exploration well in the area were composed of hard and abrasive quartzitic sandstone containing traces of pyrite and chert with interbedded hydratable shales. Penetration rates were on the order of 1 m/hr with gage wear being a major dulling condition. Roller cone bits were pulled with gage wear of up to 18 mm. Bit life was generally less than 20 meters, resulting in an extreme amount of reaming undergage hole.

An analysis of the drilling performance in this first well was performed. Several areas were identified where significant improvements in performance could be achieved on subsequent wells. The key area for overall improvement was the gage holding ability on the roller cone drill bits. Three different enhanced gage features were selected for evaluation.

Enhanced tungsten carbide gage Diamond coated heels (active diamond) Diamond coated gage (passive diamond)

This paper will examine the benefits of the revision to the drilling program including revised drilling parameters, bottomhole assemblies, and specialized roller cone bits. The impact on drilling performance and cost reduction are quantified for the 17-1 /2″ hole section in the second exploration well in this area.
Case Histories Regarding the Application of Microfine Cements
Authors: Heathman J. F. , East L. E.
Published: December 2007

Microfine cements, which are a relatively new technology to the energy-related industry, have a variety of applications for both primary and remedial cementing operations. These products have been found to penetrate passageways such as channels, gravel packs, and casing leaks that were previously unrepairable with conventional cement slurries and to have various other conventional and nonconventional cementing applications where the special properties exhibited by the fine particle sizes of these materials are desirable.

Conventional cements, when used to attempt to repair a casing leak or channel behind pipe, will typically bridge-off at the point of entry. Microfine cements, on the other hand, will penetrate a passageway in sufficient volumes to provide a boundary usually sufficient to withstand differential pressures normally encountered in drilling and production operations. Microfine cements have also been applied in squeezing off unwanted gas coning in producing zones gravel packed with 40\60 mesh gravel. In summary, high gas\oil ratio and water producing wells and wells with previously economically unrepairable pasings once considered marginally productive now have the potential to become highly profitable wells.

The subject paper presents a comprehensive review of field case histories documenting the use of microfine cements for remedial and drilling applications.
History and Development of a Rotating Blowout Preventer
Authors: Cress L. A. , Stone Rick , Tangedahl Mike
Published: December 2007

The introduction of horizontal drilling in conjunction with the "advent" (novel approach) of Flow Drilling has created a revitalized need for a Rotating Blowout Preventor "RBOP". In the 60's the original idea of an "RBOP" progressed all the way to a prototype model and then died due to other challenges facing the industry. Revitalized interest in providing a means to contain at least 1500 psi at the surface while drilling has instituted the need to produce an improved rotating blowout preventor. Both laboratory and field tests confirm. the successful manufacture of an RBOP that can assist in well control and possibly help prevent a catastrophic failure.
The IADC Roller Bit Dull Grading System
Authors: McGehee D. Y. , Dahlem J. S. , Gieck J. C. , Kost Bill , Lafuze Dave , Reinsvold C. H. , Steinke S. C.
Published: December 2007

In 1987, the LADC adopted an improved Rock Bit Dull Grading System.1 Although it was modeled after the previously used T-B-G System, it was expanded to provide a much clearer "mental picture" of a dull bit. This paper documents the changes from the 1987 version to the 1992 LADC Dull Grading System. Since the changes are minor, they are listed at the beginning of the paper. Additionally, for those needing more detail, the entire 1992 IADC Dull Grading System is presented.
First Revision to the IADC Fixed Cutter Dull Grading System
Authors: Brandon B. D. , Cerkovnik Jerry , Koskie Earl , Bayoud B. B. , Colston Fred , Clayton R. I. , Anderson M. E. , Hollister K. T. , Senger Jim , Niemi Ralph
Published: December 2007

This paper is one of two describing changes to the IADC Classification and Dull Grading Systems for fixed cutter bits. Dull grading system revisions, described herein, were implemented to improve utilization and effectiveness of the dull grading system.

Classification system changes were required as a result of improvements in bit technology and applications, and are detailed in the companion paper SPE 23940.
Development of a New IADC Fixed Cutter Drill Bit Classification System
Authors: Brandon B. D. , Cerkovnik Jerry , Koskie Earl , Bayoud B. B. , Colston Fred , Clayton R. I. , Anderson M. E. , Hollister K. T. , Senger Jim , Niemi Ralph
Published: December 2007

Following extensive review of the existing system, development of a new IADC Fixed-Cutter Drill Bit Classification System was initiated in late 1990, based on input gathered from the industry concerning the change. It was determined that existing fixed-cutter bit classifications, which attempted to describe each bit style individually, were not being used.

In contrast, the success of the roller cone bit classification system was believed to lie in its grouping of similar bit styles into categories, thus allowing users to relate familiar bit styles with unfamiliar ones.

Specifically, the IADC Fixed-Cutter Work Group committee undertaking the task developed a fixed-cutter bit reference chart patterned after the existing roller cone classification table, which would allow bit styles to be grouped by similar type. IADC classification codes for each bit are then generated by placing the bit style on the chart in the category which best describes it, thus grouping similar bit types under a single category.

The new classification system is composed of four characters, designating body material, cutter density, cutter size or type, and profile, respectively. It is presented as an attempt to improve the ability to classify and thus employ fixed-cutter PDC and diamond drill bits more effectively in the drilling industry.
Gas-Lift-Valve Test Rack Opening Design Methodology for Extreme Kickoff Temperature Conditions
Authors: Lagerlef D. L. , Smalstig W. H. , Erwin M. D.
Published: December 2007

The objective of unloading valves in a gas lift string is to transfer gas to the lift point. Normally, the valve test rack opening (TRO) for nitrogen charged dome pressure valves is based upon the estimated flowing temperature profile. This is appropriate for most situations. However, the valve settings may not unload consistently when a significant difference exists between the shut in, unloading, and producing temperature gradients. Such temperature differences are very pronounced in either high rate wells or in wells with a large upper well bore heat sink, such as when penetrating the Arctic permafrost, and in deep sea completions.

A procedure has been developed to determine an appropriate TRO for each valve to accommodate the range of temperature conditions expected during kick-off operations. It reduces the likelihood of unloading valves operating out of sequence and improves efficient transfer of lift gas to the design lift valve under a variety of well bore temperature gradients.
An Interface Model To Predict Vertical Sweep During Steamdrive
Authors: Palmgren C. T. S. , Bruining Johannes
Published: December 2007

Steamdrive is a commercially successful recovery technique for heavy oils [1]. It is also recognized as a "valid technology" for light and medium viscosity oils [2].

For slightly unstable situations steam tends to override the oil. The model proposed by van Lookeren has been extended to describe this override behaviour, by using a semi-steady state approximation for the heat transfer at the steam condensation front (SCF). In the absence of heat losses the ensuing equations are completely analogous to the equations for oil-water flow. We have also incorporated heat losses and thus developed the first simple steamdrive model which combines fluid flow and heat losses without empirical assumptions. The interface model comprises Marx-Langen heim and complete override models as limiting cases. The ensuing equations are solved with the method of characteristics.

In order to validate the theoretical model we used a scaled laboratory model. The model is transparent and experiments are performed at subatmospheric pressures. An advanced infrared scanner technique was used, together with thermocouples, to measure temperature distributions in the model. Fluid distributions and interface positions are observed visually.

The interface model describes both the convex (short term) and concave (long term) shape of the SCF and shows excellent agreement with the experimental results.
Steam Distribution Surveillance and Analysis
Authors: Peake W. T.
Published: December 2007

Mass and energy balances are presented for a typical steamdrive steam distribution system. Independent measurements of steam mass and enthalpy rates, at the generators and injection wells, are compared using these balances. This comparison and accompanying error analysis of measurements is shown to provide a check on the reliability of steam distribution data. This procedure is demonstrated on a 21-pattern steamdrive. Steam allocation factors are presented for mass and enthalpy rates.
Acquiring Production Logging Data With Pulsed Neutron Logs from Highly Deviated or Non-Conventional Production Wells With Multiphase Flow in Prudhoe Bay, Alaska
Authors: Barnette J. C. , Copoulos A. E. , Biswas P. B.
Published: December 2007

Pulsed neutron logs (PNL) are being used similar to production logging instruments to qualitatively identify gas, oil, and water entry into the wellbore. Gas, oil, and water entry are identified with the pulsed neutron log by measuring flowing and static early-time gamma ray and background gamma ray data in combination with conventionally recorded saturation data.

The PNL's best application for production logging is in difficult logging conditions—multiphase flow in highly deviated or non-conventional wells where quantitative measurements are difficult to interpret using conventional production log data. In multiphase flow conditions, the PNL can usually characterize non-uniform flow profiles, which yields similar results to those of conventional production log measurements. In non-conventional wells where flow conditions are further complicated, the PNL data are an excellent supplement to a suite of conventional production logs.

Use of the PNL for production logging offers a useful addition to conventional wellbore surveillance logging. Gas-, oil-, and water-entry data can be simultaneously acquired with conventional PNL saturation data and channel detection logging data. ‘ Simultaneous data acquisition leads to better remedial work decisions, accomplished by ensuring that all major parameters (e.g., gas-oil contact, oil-water contact, potential for cement channeling, and production entry points) are considered before making a remedial work decision.
Reserves Reporting for Decision-Making Planning and Control
Authors: Higgins J. G.
Published: December 2007

EXECUTIVE SUMMARY

This paper shows how the established Monte Carlo simulation approach to estimating hydrocarbon reserves can be expanded to provide the basis of a comprehensive valuation, planning and control system meeting all the reserve reporting requirements of an oil exploration and production company. The approach presented is also appropriate for other mining and extractive industries.

The paper demonstrates how individual expectation curves can be modified to reflect both technically and commercially recoverable reserves and how these are in turn combined into the economic valuation, planning and control processes of an enterprise. Estimates across the full range of risk and reserves can be aggregated to provide a powerful planning tool that can be used to set corporate, divisional and individual objectives. The way in which reserve estimates can be used as a sensitive control system to monitor an organisation's ongoing ability to meet its objectives is also demonstrated.
The Southern Cone Petroleum Market
Authors: Fidalgo Santiago , Astra C. A. P. S. A. , Pisani Walter
Published: December 2007

The Argentine oil sector has been moving strongly toward complete deregulation since 1989. Price controls on byproducts has been lifted, old petrolem contracts became into concessions, and the state oil company, YPF, is under process of privatization.

In this context, the international companies scouting for opportunities can find an important menu of potential investments.

But there remain some problems connected with this deregulation, too. The lack of a reference crude and product market price is one of them.

This paper focuses how to overcome this trouble with the establishment of an

References and illustrations at the end of the paper. institutional market for crude and products, not only for Argentina but also for the entire Southern Cone Region (Argentina, Bolivia, Brazil, Chile, Paraguay and Uruguay), inquiring into the benefits of its creation.

Those countries should follow Argentine steps in deregulation (more probably sooner than later). All of them, except Bolivia and Chile, have signed in 1990 the "Mercosur" treaty, which favores this type of enterprises.

Furthermore, it will be analyzed the incidence of this market in the oil trade, intraregional, or between the Southern Cone and the rest of the world.