bluuebunny/crossref_metadata_2025_split huggingface dataset:
Evaluation of Hydraulic Fracturing Applications in Central Australia
Authors: Lee B. O. , Salter G. B. 
Published: December 2007

ABSTRACT
Some low permeability reservoirs in Central Australia require successful hydraulic fracture stimulation of production and injection wells to enable economic development. The techniques available to determine the created fracture properties include post-fracture pressure transient analysis and production performance history matching. The results of such evaluation will indicate the design changes required for optimum future treatment efficiency.
The methodology of detailed well test analysis for a number of fractured wells in an oil reservoir is described. Type curves and specialized plots for individual flow regimes are used in the analysis. Post-fracture pressure transient behaviour for these wells is generally bilinear flow dominated. The analysis results are validated by production history matching and indicate that future cumulative production for most wells in this reservoir could be further increased by improvements in created fracture conductivity.
Well Spacing For Primary Production And Pattern For Secondary Production As They Might Affect Ultimate Recovery
Authors: Orr Robert M. 
Published: December 2007

Abstract
Conclusions regarding primary spacing and secondary pattern as related to ultimate recovery were drawn from observation of the performance of numerous waterflood projects in the Sand Belt Trend of the Permian Basin in West Texas and Southern New Mexico.
Noting the trend toward wider and wider spacing in solution gas drive fields and the tendency toward not drilling any new wells for waterflood development, we made a study of nine comparable fields in this area, drilled on various spacings, in an effort to find some definite answers to the relationship of well spacing to ultimate recovery.
Some rather startling performances were observed that were contrary to most of the present thinking concerning the performance of solution gas reservoirs. For example, it was found that wells drilled on close spacing produced almost as much primary oil as did wells drilled on wider spacing. On the other hand, the secondary (waterflood) recovery was so much greater in the wide spaced areas that the combination of primary and secondary turned out to be the same regardless of the original spacing. It should be pointed out that we are dealing with reservoirs that have exceptional floodable characteristics. It is not contended that all solution gas reservoirs will respond in the same manner, except as to primary producing performance.
Introduction
For the past several years the tendency has been toward wider and wider spacing in developing new oil fields. At hearings conducted by state regulatory bodies, in the literature and in papers presented at conventions appear statements indicating that spacing makes no difference in the ultimate primary recovery in solution gas drive oil fields. Continuity of permeability, as evidenced by pressure interference tests, is being considered as synonymous with drainage of oil.
Not being convinced that this was true, or even being significantly close to being true, we decided to make a study of this problem with whatever information was available.
Toughness Requirements for Downhole Tubulars
Authors: Kermani M. B. , McKendrick R. D. 
Published: December 2007

ABSTRACT
Premature and unexpected downhole failures are costly and introduce inefficiency in drilling and production operations. The integrity of tubulars used in these operations can be enhanced by reducing the risk of crack initiation through minimising the intensity of stresses ahead of existing defects, together with using materials of high fracture toughness properties.
Many material specifications now include minima for the V-notch Charpy absorption at one or more temperatures. However, Charpy values are inadequate in defining accurately the fracture toughness properties, determining the critical defect size and establishing.the conditions under which such a defect would become unstable.
Therefore, the crack tip opening displacement (CTOD) approach of general yielding fracture mechanics has been used to assess the toughness requirement of a range of downhole tubulars at ambient and various sub-zero temperatures. The materials studied included drillpipe and casing which fall within the category of API Specs 5D and 5CT and bottom hole assembly components covered by API 7A. This assessment was supported by carrying out fitness for purpose evaluations in accordance with British Standard PD 6493. Minimum safe values for the fracture toughness (CTOD values), relating to the body and threaded sections of tubulars with respect to the presence of possible defects, have been calculated.
In addition, the Charpy V-notch properties of the steels have been correlated with those of critical CTOD values. These relationships will enable materials and drilling engineers to specify adequate fracture toughness properties using relatively inexpensive and simple Charpy impact tests.
The results have clearly identified necessary toughness requirements for a range of typical tubular materials. It is recommended that a similar fracture mechanics approach, specifying the Charpy impact values, be adopted by API in future tubular specifications. This would ensure that a tubular is "fit for purpose" and thus minimise the occurrence of costly brittle failure of downhole tubulars.
Bit Whirl: A New Theory of PDC Bit Failure
Authors: Brett J. F. , Warren T. M. , Behr S. M. 
Published: December 2007

ABSTRACT
This paper presents the results of a study investigating PDC bit vibrations. The study shows that the most harmful vibrations can be attributed to a phenomena called "bit whirl". During whirl the instantaneous center of rotation moves around the face of the bit, and the bit backwards whirls around the hole. Cutters on a whirling bit can move sideways, backwards, and much faster than those on a true rotating bit. The impact loads associated with this motion cause PDC cutters to chip, which, in turn, causes accelerated wear. Lab and field results showing the detrimental effects of whirl on PDC bit penetration rate and life are included.
Monte Carlo Simulation of Lithology from Seismic Data in a Channel-Sand Reservoir
Authors: Doyen P. M. , Guidish T. M. , de Buyl M. H. 
Published: December 2007

Abstract
In areas of rapid lithologic variations, the areal extent of sand and shale units usually cannot be inferred from sparse well data alone. Seismically derived interval velocity data can be used to help predict lithologic variations away from wells. However, in general, the overlap of the velocity ranges for sands and shales is such that seismic discrimination of lithology is ambiguous. We present a Monte Carlo technique for numerically simulating the spatial arrangement of sand/shale units. This technique accounts for the ambiguous nature of the seismic velocity information. Rather than calculating a unique sand/shale model, the Monte Carlo method provides a family of alternative lithologic images, all of which are consistent with the data. The range of models reflects the uncertainty of the lithologic classification and is used to assess risk in reservoir development. The sand/shale simulation technique is illustrated using a data set from an oil-producing channel-sand reservoir. Sand/shale cross-sectional simulations are generated along a seismic traverse that intersects three wells. The simulated models reproduce the log-derived lithologic sequences at the wells; they are conditioned by interval velocities inverted from the seismic amplitude data and are consistent with the spatial autocorrelation and cross-correlation structures of the seismic and well data. The seismically derived lithologic models of the reservoir are better spatially constrained than models solely conditioned by well data. However, in keeping with the inherent ambiguity of the seismic information, the exact location of the lateral truncation of the channel sand is not precisely defined in the Monte Carlo lithologic simulations.
A Structured Approach to Bridging the Research to Application Gap
Authors: Patel M. H. 
Published: December 2007

Abstract
This paper presents the historical background and structure of a joint industry funded international research programme which is specifically designed to be a bridging activity between fundamental work in research laboratories and the realities of practical application. The structure of the programme is described in detail including the procedures for organising funding, setting priorities and in managing the interface between research and application to ensure effective technology transfer. The concepts and philosophy underlying such a research programme are illustrated by drawing on five years experience of running one such programme entitled ‘Integration of Design Techniques for Offshore Structures’ at University College London.
International Implications of Technological Leadership: Part C—Worldwide Technical Organization
Authors: Grijalva V. E. 
Published: December 2007

Abstract
The international arena, specifically areas outside of North America, has increased in importance to those searching for oil and gas, for both economic and resource availability reasons. This creates a challenge to those accustomed to conducting business largely in the U.S. in best deploying their personnel and technological resources in an expanding international marketplace. Accordingly, this article addresses:
How can a technology-based company best structure itself to provide professional services and/or products throughout the world?
No stranger to the international marketplace, Schlumberger has had one mission from its inception--to provide the oil industry with value services to find and produce oil and gas efficiently and safely. From this broad philosophical foundation, the company has spent over sixty years molding an organization that will sustain its international focus on quality technology and service.
It is this organization that will be discussed herein, with the goal of identifying operational concepts and procedures that may help others to effectively disseminate and apply the latest petroleum technology worldwide.
A Comparison of Unstable Miscible and Immiscible Displacements
Authors: Peters E. J. , Hardham W. D. 
Published: December 2007

Abstract
Flow visualization experiments were conducted to compare the insitu displacement mechanisms of unstable miscible and immiscible displacements. A number of corefloods were imaged in time and space using x-ray computed tomography.
Results show that three displacement mechanisms are active in unstable miscible displacements whereas only one of these mechanisms is active in immiscible displacements. Therefore, unstable miscible displacements are more efficient than their immiscible counterparts because of a fundamental difference in their displacement mechanisms.
The Thin Flame Technique for In-Situ Combustion Simulation
Authors: Davies R. J. 
Published: December 2007

ABSTRACT
This paper describes an approach taken to overcome the problems caused by grid block size effects in field scale in-situ combustion simulations. A new method called the thin flame technique is presented which approaches the problem by decoupling the flame from the conventional finite difference simulator and solving seperately for the flame speed and reaction rate. The thin flame technique uses the flame speed and reaction rate to advance a thin boundary representing the flame through the grid. This boundary acts as a moving heat source and displacing pump.
The solution of the decoupled flame is achieved using a steady state analysis that models the burning region using a reduced set of the conservation equations, and applies a moving grid to the region resulting in a two point boundary value problem. This is solved using a simple shooting method. The steady state analysis is derived for a system modelled by a single chemical reaction, and its solution by the shooting method is described. The analysis is compared with experimental results giving good agreement for the flame parameters.
The reaction rate and flame velocity determined by the steady state analysis are then used to apply the thin flame technique to the conventional simulator. This requires the redistribution of components within the burning grid block in order to correctly represent the saturations in the flow terms and provide boundary values for the steady state analysis. The application of the technique is described and results are presented of comparisons with the conventional simulator.
Miscible Flood from Inception: The Brassey Field Development, British Columbia, Canada
Authors: Whitten M. D. , Anderson J. H. , Tinker G. E. 
Published: December 2007

Abstract
The Brassey field, located in northeast British Columbia, Canada, is a dune sand reservoir, containing a volatile, undersaturated oil. The "Artex" sand is approximately 12 feet thick and is interpreted to be part of a large aeolian complex. Primary recovery is uneconomic, so a miscible flood will be operated from inception. Development of this oil-wet reservoir required the simultaneous integration of petroleum engineering and geoscience disciplines. A British Columbia Provincial Government 24 month royalty holiday program encouraged the pursuit of an aggressive development plan. This resulted in final development drilling being conducted during the miscible flood facility installation.
Development was started by implementing an extensive seismic acquisition and pulse testing/pressure transient program to determine reservoir boundaries and continuity. The ultimate well density, pattern design, and well location were altered prior to startup, based on this program. Fundamental reservoir engineering methods were applied in determining oil-in-place, performance predictions, and the necessary EOR process.
Future Trends in Drilling Costs: A Cost-Based Perspective
Authors: Woods T. J. 
Published: December 2007

ABSTRACT
U.S. drilling costs have fallen substantially since the 1982 peak reported in the Joint Association Survey. In 1987 average U.S. well costs were 54 percent of their 1982 peak. The decline in drilling costs has essentially offset the decline in gas and oil prices between 1981 and 1987. Nevertheless, drilling activity has declined substantially. The combination of lower drilling activity and lower charges for drilling has affected the financial health of the U.S. drilling and service industry, even though the Industry is substantially more efficient today than it was in the early 1980s.
If drilling activity is to recover in the future, drilling charges will have to recover to support the expansion of the drilling and service industry. These charges, however, will only be able to recover to the extent that resource economics will allow. If resource economics constrain the recovery of drilling charges, such that the drilling industry can only expand modestly, then the outlook for U.S. oil and gas production could become less optimistic. Therefore, the economics of the optimistic. Therefore, the economics of the drilling and service industry is as important to future U.S. oil and gas production as the outlook for oil and gas prices.
Analyzing the Flowing Performance of Oil Wells: Denver Unit CO2 Flood
Authors: Greene W. R. 
Published: December 2007

Abstract
A mathematically precise method for determining the flowing life of oil wells is presented. Development of the necessary "outflow performance curves" and "flow charts" using multiphase vertical flow calculations is explained and illustrated graphically. An example study of 377 wells in the Denver Unit CO2 flood in the Wasson (San Andres) Field, Texas, is used to demonstrate this calculation procedure.
Requirements for Corrosion-Resistant Alloy (CRA) Production Tubing
Authors: Petersen C. W. , Bluem M. F. 
Published: December 2007

Abstract
The incentive to use corrosion-resistant alloy (CRA) production tubing has grown as bottomhole temperatures have steadily increased above 325°F, as corrosion control costs have grown, and as many operations have sprung up in remote sites with limited accessibility. This paper discusses procedures to ensure acceptable manufacture of such tubing and also presents some operational experiences with these alloys.
Behavior of Coal-Gas Reservoirs
Authors: Cervik Joseph 
Published: December 2007

American Institute of Mining, Metallurgical, and Petroleum Engineers, Inc.
This paper was prepared for the SPE 4th Annual Eastern Regional Meeting to be held in Pittsburgh, Pa., Nov. 2–3, 1967. Permission to copy is restricted to an abstract of not more than 300 words. Illustrations may not be copied. The abstract should contain conspicuous acknowledgment of where and by whom the paper is presented. Publication elsewhere after publication in the JOURNAL OF PETROLEUM TECHNOLOGY or the SOCIETY OF PETROLEUM ENGINEERS JOURNAL is usually granted upon request to the Editor of the appropriate journal provided agreement to give proper credit is made.
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.

Abstract
Gas occurs in coalbeds in an adsorbed and a free gas state. Adsorbed gas is stored in the micropore structure and its transport is governed by Fick's law. The free gas occurs in the fracture system and flows according to Darcy's law. These two modes of mass transport are interdependent. Production decline curves are of the constant percentage decline type and, thus, show no indications of flow characteristics peculiar to coal-gas reservoirs. The effectiveness of surface boreholes as a degasification scheme depends upon both good fracture permeability and a high fracture density. Conventional methods of reservoir engineering analysis are not applicable to coalbeds.

Introduction
Mining of deep coalbeds (1,500 to 2,000 ft.) and production of the associated gas is analogous to a gas well with an expanding well bore radius. Gas production of 10 to 15 MMscfd is not uncommon from deep mines. State and Federal codes require that each unit vol. of gas be diluted with approximately 100 vol. of air. Methane-air mixtures in the range 5 to 15 pct. methane are explosive.
Mining deeper coalbeds requires smaller mine openings and these mines tend to be more gassy. Thus, the use of ventilation (dilution) as a means of controlling methane concentrations at active face areas and in the returns is limited severely. Degasification of coalbeds prior to mining and methods of controlling the flow during mining are necessary. Before effective methods of control and degasification can be developed, the laws governing mass transport through coalbeds must be understood.
The purpose of this paper is to present the fundamental concepts governing the transport of gases through a coalbed, and to define one of the environmental problems related to rapid, economical, and safe mining of coal deposits.

MICROPORE STRUCTURE OF COAL
Coal is formed from plant substances which mere preserved in various states of degradation in a favorable environment, and later altered by chemical and physical processes. However, there is no universal agreement on what chemical and physical changes take place in the transformation of plant substances to coal.
A New Technique for Laboratory Measurement of Acid Fracture Conductivity
Authors: Malik M. A. , Hill A. D. 
Published: December 2007

Abstract
A new type of cell has been developed and tested which can be used in the laboratory to simulate acidizing of a vertical fracture with and without fluid loss. Also, the acid-etched fracture conductivity can be measured under various levels of load.
Five experiments have been performed with this cell using Indiana limestone or Glen Rose limestone for acidizing and conductivity measurement. In two of these experiments, fluid loss was allowed from the fracture walls during acidizing. The etching patterns observed differed markedly from those seen in a cell in which the flow was radial through a horizontal fracture. The measured fracture conductivities dropped sharply at closure stresses of 3000 to 4500 psi, apparently due to crushing of the etched fracture faces.
553-ft Gravel Pack Uses Clarified XC Polymer: Development and Application in Beluga River, Alaska
Authors: Engel H. R. , Powell J. W. , Sigurdson S. R. 
Published: December 2007

ABSTRACT
ARCO Alaska, Inc. (AAI) began using a clarified xanthan gum (XC) biopolymer to viscosify gravel pack slurries in 1987. More effective polymer hydration and filtration techniques were developed during several field applications. Current methods not only simplify the preparation of this xanthan polymer at the well site, they improve fluid quality, producing filterability without the use of shearing devices and resulting in higher values for low shear rate viscosity in the filtered fluid.
In addition to the mixing technique being refined, the method of gravel placement also was modified. The changes in the placement procedure allowed the perforations to be packed with the gravel pack screens in the well, and led to a successful 553 ft zone gravel pack.
This paper will document how the current polymer preparation technique was developed and how the slurry placement procedure was applied. It also will stress the importance of onsite quality control to a successful gravel pack.
Proppant Flowback Control
Authors: Murphey J. R. , Dalrymple D. , Creel P. , Totty K. D. , Crump B. , Barr S. 
Published: December 2007

ABSTRACT
A process for controlling proppant flowback after hydraulic fracturing operations has been developed and extensively field tested. In the procedure, fracture sand is coated with epoxy resin during the fracturing treatment. Unique wetting aids permit the rapid and complete epoxy resin coating of the sand while it is in the blender tub. Once placed in the fracture, the resin coated sand hardens to form a highly conductive, consolidated proppant bed which is resistant to flowback.
Fluid residence times and mixing parameters required to obtain rapid resin coating of sand were studied utilizing a laboratory scale blender to simulate typical fluid rates and mixing energy. Fracture flow capacity and compressive strength development with respect to application parameters were determined.
This paper presents results of field testing of this method and the development of metering and mixing equipment required to perform this process.
Vertical Permeability: Field Cases
Authors: Bourdarot G. , Daviau F. 
Published: December 2007

ABSTRACT
This paper compares the vertical permeability of several field cases, as obtained using different techniques.
The vertical permeability of a reservoir is often of major importance: –where water or gas coning is likely to be a problem,–when pressure maintenance is carried out in multi-layer reservoirs,–in many reservoir simulation studies,–if horizontal wells are envisaged.
The following methods were used to determine the vertical permeability: –well test analysis: partial penetration, multilayer and horizontal well tests in both conventional and fractured reservoirs,–coning analysis,–RFT vertical gradient and build-up analysis.
A comparaison of the vertical permeability values obtained, using the various methods listed above, makes it possible to establish the interpretation consistency.
A comparison with core measurements makes it possible to evaluate reservoir homogeneity. When vertical permeability is measured from cores it is generally higher in comparison to measurements obtained using dynamic methods. This is because core measurements do not allow for middle scale fluid barriers.
Dynamic measurements of vertical permeability combined with statistical methods help determine the magnitude of fluid barriers causing permeability anisotropy in the reservoir.
In fractured reservoirs, vertical permeability is often low as a result of discontinuity of the fractures at the bedding planes. Well tests and coning analysis are the best methods for determining vertical permeability and evaluating fracture continuity in the reservoir.