bluuebunny/crossref_metadata_2025_split huggingface dataset:
Coalbed Hydraulic Fracture Treatment Empirical Relationships and Computer Simulation
Authors: Jones A. H. , Bell G. J. , Morales R. H. 
Published: December 2007

ABSTRACT
The stimulation of gas flow from coal seams by hydraulic fracturing has been pursued in the U.S. for more than ten years. However, there currently is no concensus among the industry as to the best approach for coalbed stimulation design; there are many different fracturing techniques used by operators.
Under sponsorship of the Gas Research Institute, data on more than 130 separate hydraulic fracture treatments in coal were acquired from the industry. An empirical study of fracture treatments in coalbeds of the Black Warrior Basin in Alabama reveals a trend for the maximum treatment pressures observed during hydraulic fracture treatments in coal to approach twice the values of the minimum horizontal stresses. This trend far exceeds the observed maximum treatment pressures in conventional sandstones at equivalent depths.
To enable simulation of such high treatment pressures, several physical mechanisms were investigated, including pressure buildup due to fluid leakoff, multiple fracture propagation, high viscosity fluid due to coal fines generation, and fracture-tip plugging. A 3-D hydraulic fracture computer code was modified to account for an incomplete fracture-tip screenout due to coal fines plugging within the fluid pad. The ensuing fracture treatment predictions more closely reproduce field results and provide better insight to the proper design of fracture treatments in coal deposits.
A Leading Index of Drilling Activity: Update and Improvements
Authors: Buell R. S. , Maurer R. A. 
Published: December 2007

ABSTRACT
A five-component composite leading index of United States rotary rig drilling activity is updated. The index is presented for 1949 through April 1986 and is shown to consistently lead turning points in drilling activity. Seven new leading indices based on some new components are also presented. A forecast of drilling activity is made for the remainder of 1986 based on the leading index and the current economic condition of the petroleum industry. The methods used to prepare time series and construct indices are reviewed.
Drilling a 26-in. Diameter Hole to 12,550 ft: A Case History
Authors: Fontenot E. P. 
Published: December 2007

ABSTRACT
Standard Oil Production Company (SOPC) drilled a 26" diameter hole to a world record depth of 12,550'. Although a number of holes of this diameter had been drilled to depths on the order of 7000' to 9000', most had not been drilled through geologic formations as old with rock as competent as encountered in this well. This paper discusses the drilling challenges encountered during the course of this drilling operation. Through planning, careful detailed research into equipment design, and close field observation, solutions to problems encountered under relatively severe, drilling conditions were developed. The successful drilling of this portion of the well allowed SOPC to set a world record string of 20" casing and ultimately led to the programmed objective of reaching a total depth of 25,015' in a hole size of 8-1/2".
Advanced Field Automation in the Tuscaloosa Trend
Authors: MacDonald T. E. 
Published: December 2007

ABSTRACT
The Tuscaloosa Automated Production System (TAPS) was developed in response to the difficult producing environment of the Tuscaloosa deep gas trend. It has subsequently been expanded to include a waterflood project in a shallow oil field. This paper illustrates how TAPS transforms field automation into a simple tool that the entire staff can use to optimize and analyze field conditions.
Examples of features such as the annunciator, schematic diagrams, and process control demonstrate the system's ability to aid in field operations. Other options including online history, real time data graphs, and automatic reporting show how automation is used to analyze field conditions. Four years of experience have proven these features enable both field and office staffs, that have no "computer" training, to use the system as an integral part of the daily producing routine.
Polymer Mud vs. CLS-Lig in Normal Pressure Applications: South Texas
Authors: Koenig R. L. 
Published: December 2007

Abstract
Exxon Company, U.S.A., South Texas, has recently employed the use of a polymer drilling fluid system in 68 drill wells with encouraging results. Both drilling and production related benefits have been observed on many of the wells using the polymer system when compared to those drilled with conventional chrome lignosulfonate mud. These benefits include: 1) increased ROP, 2) improved bit life, 3) better solids control, 4) reduced hole enlargements, and 5) improved completion success. Additionally, these benefits have been achieved at lower overall intangible costs than comparable wells drilled with chrome lignosulfonate mud.
This paper summarizes some of the advantages of the polymer system relative to chrome lignosulfonate mud as observed from actual field comparisons. It includes a thorough discussion of the polymer system and the various products used in make up of the mud. Factors that contributed to the improved performance are discussed in detail. Problems experienced in the use of the system with possible explanations are also provided.
A Comparison of New Ultrasonic Cement and Casing Evaluation Logs With Standard Cement Bond Logs
Authors: Sheives T. C. , Tello L. N. , Maki V. E. , Standley T. E. , Blankinship T. J. 
Published: December 2007

ABSTRACT
New ultrasonic inspection techniques have been implemented to evaluate cement bond and casing conditions. These techniques, relying on state of the art downhole, high-speed waveform digitization, can successfully determine cement voids and channels and also provide accurate bond information in the presence of a microannulus. The downhole microprocessor controlled electronics transmits the digitized waveforms to the surface for computations and display. The downhole waveforms are then viewed by the operator in real time to insure proper log quality. Numerous log examples showing comparisons with the standard Cement Bond Log (CBL) demonstrate that the accuracy and resolution of the new approach provide much more information.
Casing conditions are determined using both acoustic caliper measurements and a new casing thickness measurement technique. The acoustic caliper measurement not only determines accurately the casing inside diameter, but also detects the pipe gap at casing collars. The new measurement determines actual casing thickness variations due to internal or external pipe wear or corrosion. Experimental results along with log examples show the effectiveness and accuracy of measuring the actual casing thickness at the well site in real time.
A New TFL Test Centre in Norway
Authors: Tailby R. J. , Christensen O. S. , Aarrestad S. , Maddux G. D. 
Published: December 2007

ABSTRACT
A TFL test centre has recently been built in Stavanger, Norway, with the aim of qualifying TFL equipment and techniques for use in subsea wells.
This equipment is presently being testing in a 660 ft (200 m) horizontal loop, to which a 5000 ft (1500 m) flowline has recently been added. A well is planned for 1987. All surface facilities are indoors, and all-weather capability has been achieved.
Problems have occurred with the test equipment and the facilities which have provided inexperienced personnel with valuable and relevant on-the-job training. After one year's operation, the test centre is rapidly proving its worth and generating a better understanding of TFL in Norway.
Successful Salvage and Tie-Back Operations for a Hurricane-Damaged Satellite Well in the Gulf of Mexico
Authors: McCutcheon J. B. , Payne M. L. 
Published: December 2007

Abstract
The Eugene Island Block 174 Well No. 3 was producing 1000 B0PD before it was blown over by Hurricane Danny in August, 1985. The well was located offshore Louisiana in 80′ of water. The 60″ OD x 1.75″ wall caisson which supported the satellite well was sheared in two at four feet below the mudline, while the upper portion of the well was bent 85 degrees from vertical. Taking into account the severe bending of the tubing and casing, reduced pressure ratings were calculated and the well was killed. Successive windows were cut in the casing by divers to evaluate the inner pipe strings for salvageability. The tubing strings were plugged with cement and the well was severed at the bend area with high explosive shape charges. The casing stubs were dressed off and the well tied back. The successful salvage operation achieved a two million dollar cost savings when compared to drilling a replacement well.
Discussion of 1986 SPE Manpower Survey
Authors: Calhoun J. C. 
Published: December 2007

ABSTRACT
1.) Twenty nine companies responded to the survey in 1986. Data covering all aspects of the survey were available in 22 of the replies, but for some aspects of the analysis as many as 27 replies were usable. In terms of numbers of engineers employed at the end of 1985, the distribution of company sizes for the 27 companies was:
2.) Year-end employment of engineers for 27 companies is shown in Figure 1. Year-end employment figures for those with petroleum engineering degrees were available only for 25 companies, and this is also shown in Figure 1 and tabulated in Table I. These companies, over the five years, reported 25% of their engineering work force to be petroleum engineers, although the percentage rose continuously from 21.9% in 1981 to 29.6% in 1985. The total engineering work force showed its lowest point in 1983. The petroleum engineering work force on the other hand showed a continuing increase over the entire five years.
3.) Employment and projection estimates were available for only 25 of the responding companies. Some respondents felt the current situation to be too unstable to permit any kind of projections. Figure 2 and Table II shows the projections to vary from an increase of 17.5% over the next five years to a decrease of 10.1%, but both high and low projections show a lesser total employment of engineers for both 1986 and 1987 than in 1985. The drop projected from 1985 to 1986 is not so large as would be expected from recent reports of retirements and layoffs that have been circulating, although the low projection for 1986 shows 15.4% less than 1985.
Basic Concepts in Static BHA Analysis for Directional Drilling
Authors: Chandra U. 
Published: December 2007

ABSTRACT
Basic concepts related to the static analysis of two-and three-dimensional bottomhole assemblies are discussed. Beginning with a straight one stabilizer assembly, the effects of multiple stabilizers, borehole curvature, torque, wall contact, etc. are introduced in steps. The criteria for defining the build, hold, drop and walk trends is clarified. Two methods for computing bending stiffness and equivalent outer diameter of MWD collars with nonuniform cross-sectional properties are proposed. Also, simple methods of estimating buckling loads for one and two span assemblies are presented.
Design and Implementation of Immiscible Carbon Dioxide Displacement Projects (CO2 Huff-Puff) in South Louisiana
Authors: Palmer F. S. , Landry R. W. , Bou-Mikael S. 
Published: December 2007

ABSTRACT
The CO2 Huff-Puff (Immiscible Carbon Dioxide Displacement) process is described including reservoir mechanics. The planning, design, and implementation of the projects including the equipment specifically designed and constructed for these projects are discussed. Case histories of selected projects are included. The paper contains field operations detailing the problems encountered and subsequentially corrected.
Techniques for Planning and Execution To Improve Foam Cement Job Performance
Authors: Kulakofsky D. S. , Creel P. G. , Kellum D. L. 
Published: December 2007

ABSTRACT
A study of foam cement job results and laboratory data shows improved bond log performance, reduced planning time, and significant cost savings from using computer modelling and refined job procedures.
The computer model considers the most complex well conditions while still accounting for the continuously changing friction factors and density of an expanding or compressing foam. Elements of information predicted by the model are (1) pump rates, (2) surface pressure, and (3) nitrogen concentration. The model also gives an indication of the need to foam mud and/or spacers. These elements are based on predicted downhole circulating density, which is the prime factor determining the ultimate success of a foam cement job. A comparison of predictions to actual job results is presented.
When running a foam cement job, operators have historically attempted to either (1) maintain constant nitrogen levels, or (2) maintain constant density. Subject paper compares the two philosophies and recommends, based on analysis of six years of field results, what the authors consider the optimum approach. Aspects of the two philosophies selected for comparison are (1) circulatability of the cement throughout the job, (2) competency of the cement, (3) ease of job design, (4) ease of operation, and (5) feasibility.
Field results, laboratory data, and bond logs are presented which demonstrate (1) substantial reduction in cost per cement job, (2) elimination of surface water flow, and (3) probable long term production increases brought about by reduction of cement invasion into weak, producing formations.
A Second Look at the Chapman, Deep (Fusselman) Field
Authors: Prentice R. S. 
Published: December 2007

ABSTRACT
A case history of a deep gas reservoir in the Delaware Basin of west Texas in which the water table acted erratically is presented. Gas wells in the Chapman, Deep (Fusselman) Field in Reeves County were watered out unpredictably by a strong edge or bottom water drive. Water coning, a process in which the water table selectively sought out low pressure sinks at producing well bores, was postulated.
Unswept pockets of gas in between the cones were also postulated. ARCO Oil and Gas Company tested the theory by recompleting an existing well on their Agnes Beckham "26" lease and found commercial quantities of gas. Under favorable economic and operating conditions, development of these unswept pockets may be feasible in this and other deep gas reservoirs.
A Laboratory Study of the Use of Subsurface Hydraulic Mining of Tar Sands
Authors: Marsden S. S. , Walter J. 
Published: December 2007

ABSTRACT
We have experimentally studied subsurface hydraulic mining of tar sands which involves drilling a borehole into the sand; casing it; pumping aqueous solution down tubing with horizontal nozzles near the bottom, to use the erosive action of jets for pulverizing the tar-sand mixture and finally returning the slurry to the ground's surface for future processing.
Stratigraphic Interpretation Using Formation Imaging and Dipmeter Analyses
Authors: Grace L. M. , Luthi S. M. , Pirie R. G. 
Published: December 2007

ABSTRACT
Successful stratigraphic interpretation depends on the analysis of several parameters. For many years, the dipmeter has been the key logging tool in stratigraphic interpretation. However, the nature of the measurement (four to eight microresistivity curves from four pads) placed some limits on a detailed interpretation beyond the wellbore. The recent development of 54 clustered microresistivity curves from two of the four dipmeter pads now provides two continuous side-by-side images oriented at 90° to each other. In an 8-in. hole, for example, the images cover 22% of the sedimentary formation exposed in the wellbore. The images characterize stratigraphic discontinuities (unconformities, erosional contacts), bedding thickness (thick bedded to laminated) and types (flaser, graded), sedimentary structures (crossbedding, bioturbation, deformational), and rock textures (conglomerates, breccias, shaly sandstones). Images of these oriented sedimentary features, in combination with conventional dipmeter interpretation, define the stratigraphic units and the reservoir geometry beyond the wellbore. Two case studies, including whole core analyses, are used to demonstrate the synergism between formation imaging and dipmeter interpretation.
Derivative of Pressure: Application to Bounded Reservoir Interpretation
Authors: Proano E. A. , Lilley I. J. 
Published: December 2007

ABSTRACT
This paper presents the application of the derivative of pressure technique, through a process of pattern recognition, to identify bounded reservoir behaviour under both drawdown and build up conditions. During a well test, the flow and shut in sequence should be carefully selected to optimise the response which will, in turn, enable easier recognition of the outer boundary configuration and reduce the problems of non-uniqueness. With the evolution of high resolution and accuracy pressure gauges, and the introduction of simultaneous downhole flowrate and pressure measurement, convolution techniques should also be utilised to enable the analysis of previously uninterpretable drawdown data.
The pressure derivative technique provides a systematic and global approach to describe the late time features. With this technique, there is no need to resort to specialized analysis methods or correlations for well behaviour in bounded reservoirs, which are available for limited geometries and can yield erroneous results.
Due to the unusual outer boundary features now exhibited by a large number of current well tests, there is a growing need to develop better models to describe their effects. There is an even greater need to incorporate these findings with other sources of data for appropriate dynamic bounded reservoir description.
Three field examples are presented which illustrate the problems associated with interpretation of buildup data when drawdown analysis has not been possible.
North Sea Field Development: Historic Costs and Future Trends
Authors: Thomas W. A. 
Published: December 2007

ABSTRACT
This paper reviews United Kingdom Continental Shelf (UKCS) field developments to date for technical features, development timescales and economics. Current UKCS field development trends are identified, including use of subsea completions and floating production platforms for development of small deep-water fields.
Economic comparisons are presented for a range of field developments under existing UK tax and fiscal regimes. The effects of unstable oil prices on rates of return are discussed, together with the effect of tax changes on field economics.
Reperforating Depleted Gas Wells in the Southern North Sea
Authors: Potts M. 
Published: December 2007

ABSTRACT
Reperforating is an accepted method for reducing near wellbore pressure drop. This paper details an evaluation of the effects of reperforating upon reservoir parameters and flow profiles in depleted gas wells; the basis for the evaluation was a programme of reperforating carried out during 1985 by Amoco (UK) Exploration Company in the Indefatigable gas field in the Southern North Sea. In addition to increasing well deliverability, the aim of the programme was to use testing and production logging both before and after reperforating to evaluate its effectiveness. Two new techniques which were used are also described. These are the use of a pressure gauge in combination with a strip perforating gun, and a new design of overboard boom as part of the surface equipment.
Will Very Large Modules Reduce the Cost of Offshore Platforms?
Authors: Plowden D. , Allen R. E. 
Published: December 2007

ABSTRACT
The new generation of heavy lift vessels has stimulated the design of offshore platform topsides using modules up to 7000 metric tons (or more). These very large modules will reduce the cost of offshore hook-up. However, the hook-up cost reduction may not be as great as expected and other costs should be offset against these savings.
Field Development Planning for the Heidrun Field
Authors: Till M. V. , Sauer C. W. , Smith J. E. 
Published: December 2007

ABSTRACT
The Heidrun Field was discovered in March, 1985 in Block 6507/7 of the Norwegian sector of the North Sea. Partners in the block are Conoco Norway Inc., Operator (30%), Den norske stats oljeselskap a.s, (50%), Arco Norway Inc., (10%), and Tenneco Oil Company Norsk A/S, (10%). Reservoir delineation has begun with three additional wells drilled to date.
The Heidrun Field lies under 350 m (1150 ft) of water in Blocks 6507/7 and 6507/8. The average reservoir depth is 2375 m (7800 ft) subsea. The hydrocarbon bearing strata are predominantly unconsolidated sands which exhibit varied sedimentology, mineralogy and permeability through the section.
A variety of drilling and completion challenges will arise in order to fully exploit the reserves. Due to the relatively shallow depth of the reservoir and the areal extent of the sands. These include the following: High angle drillingPossible sand control measures over long sectionsHigh production rate completion practices
This paper deals with preliminary drilling and completion considerations. Items covered include reservoir modelling for well requirements; well flow analysis for well capability; structure requirements to meet various alternatives; subsea well alternatives; and sand production prediction studies to help determine completion techniques.
A Computer Monitoring System for Reservoir Management in Southern North Sea Gas Fields
Authors: Edwards P. J. , Hughes T. 
Published: December 2007

Abstract
Amoco (U.K.) Exploration Company, as operators in the Leman and Indefatigable Fields in the southern North Sea, have developed a computer monitoring system to facilitate reservoir management of the 118 producing wells.
The main database for the system is provided by a daily record of the individual well flowrates and pressures. The principle function of the system is to compare these values with those predicted by well test data. The results are stored and in time the history of a well's production is established.
These comparisons enable both short-term and long-term well problems to be identified and action appropriately directed to remedy them.
A New Method of Measuring Gas Compressibility and Gas Gravity
Authors: Pilcher V. B. 
Published: December 2007

ABSTRACT
Practically all metering devices used in the oilfield today require some correction factor for gas gravity and gas compressibility factor (Z factor) in their calculations. An error in either gas gravity or Z factor could potentially make a significant difference in these calculations. The accepted method of calculating the Z factor uses critical property and gas gravity correlations. The proposed method allows for the calculation of the Z factor by direct field measurements.
A critical flow nozzle can be used in conjunction with a thermometer, turbine meter, and differential and static pressure gauges to allow direct measurements at the wellhead. A simple computer program then uses these measurements to calculate both Z factor and gas gravity. The paper describes the test apparatus and the calculation procedure.
New MWD Applications Using a Slimline Fully Retrievable MWD Tool
Authors: Henderson B. , Cluchey M. O. 
Published: December 2007

Abstract
A new, slimline, fully-retrievable, Directional MWD tool (DMWD®), is finding new applications for and benefits from MWD. Case histories illustrate how compact size and full retrievability are extending MWD into areas of high stuck-pipe risk, small holes, high-temperature drilling, low-budget wells, and remote locations.