bluuebunny/crossref_metadata_2025_split huggingface dataset:
Analysis of Pressure and Pressure Derivative without Type-Curve Matching – III. Vertically Fractured Wells in Closed Systems
Authors: Tiab Djebbar 
Published: December 2007

ABSTRACT
This paper is the third of a series of papers which discuss the application of the direct type curve synthesis technique for interpreting pressure transient tests in various reservoir systems. This new technique analyzes log-log plots of pressure and pressure derivatives without using type curve matching. This new approach is applied in this paper to the case of vertically fractured wells in closed systems. Both uniform flux fracture and infinite conductivity fracture cases have been investigated using log-log plots of pressure and pressure derivative functions.
For the uniform flux fracture case, pressure derivative plots for various xe/kf, ratios reveal three dominant flow regimes. During early times the flow of fluids is linear and can be identified by a straight line of slope 0.5. The linear flow line is used to calculate the half-fracture length. The infinite acting radial flow regime, which can be identified by a horizontal straight line, is dominant for xe/kf&gt;8. This flow regime is used to calculate permeability and skin. The third straight line, which corresponds to the pseudosteady flow regime, has a unit slope. This line is used to calculate the drainage area and shape factor. Several simple equations have been derived using the time of intersection, and slopes of these three lines. These equations can be used for verification purposes or for calculating reservoir parameters if one of the flow regimes is missing such as in short tests.
For the infinite conductivity fracture case, pressure derivative plots reveal a fourth dominant flow regime, called here the bi-radial flow. This flow regime, which corresponds to the transition period between the early-time linear flow regime and the infinite acting radial flow regime, can be identified by a straight line of slope 0.36. The bi-radial flow regime can be used to calculate the half-fracture length, in the absence of the linear flow line. The permeability can also be obtained from this regime if the radial flow regime is not dominant, such as when xe/kf≤8. A step-by-step procedure is provided for calculating reservoir parameters of a vertically fractured well inside a closed system.
3-D Visualization in the Gravel Placement Process
Authors: Nguyen P. D. , Smith E. L. , Fanty S. D. , Woodbridge G. A. , Weaver J. D. , Restarick H. L. 
Published: December 2007

ABSTRACT
A visualization software tool has been developed to aid in the analysis of the numerical output generated by a 3-D gravel pack simulator. The tool provides animated 3-D graphics showing the condition of moving fluids and the progress of gravel placement within the wellbore. The advantages, limitations, and pitfalls in implementing the 3D visualization for analysis of gravel pack simulation results are addressed.
A New Gravel-Sizing Computer Package for Effective Sand Control Design and Evaluation
Authors: Oyeneyin M. B. , Peden J. M. , Ren Guowu , Bigno Yann , Hosseini Ali 
Published: December 2007

ABSTRACT
In this paper the details are presented of a software package which represents a new strategic approach to the selection of an optimum gravel size for effective sand control. The new approach not only considers the formation sand size distribution in the choice of the gravel to use, it goes further to evaluate the response of the probable gravels to operating conditions and the overall effect on the well production capacity
This software package which operates in a DOS ‘pseudo’ Window environment is developed on the premise that the best gravel size selection is a function of not only the formaton sand size distribution but also other characteristics such as sand sorting and shape, gravelpack structure which dictates the pack pore throat distribution, and operating conditions and the overall effect on the well production capacity.
The design and evaluation tool is made up of: A gravelpack structure simulator (Package 1) whose primary function is to carry out a 2-D/3-D simulation of the gravelpack structure from which the maximum pore throat distribution and corresponding poroperm data and pack structure coefficient are computed.The gravel sizing package(Package 2) which is the main subject of this paper is made up of three distinct but interrelated modules namely, the pack structure module, the bridging efficiency module and the well performance module. The possible gravels to use are selected with the pack structure module which permits history matching of the formation sand size distribution with the corresponding pore throat distribution of select gravels. The bridging efficiency module thereafter evaluates the bridging effectiveness of the selected gravels and the probable gravel is finally selected on the basis of the overall well performance evaluation.
Specific case studies have been considered to demonstrate the use of the package.
Object-Oriented Finite Element Analysis and Its Application in Basin Modelling Software
Authors: Ferguson J.C. , Iliffe J.E. 
Published: December 2007

Abstract
Object-oriented software design has provided many benefits to the development of scientific software by encapsulating the attributes and behaviour of models into separate entities or objects that can interact with other objects in the software project. Objects communicate via message passing not by external reading and writing of an object's attributes. This results in more maintainable code since variables can only be modified by the object's own methods. Furthermore, inheritance creates opportunities for extensibility. Finite Element Analysis is a powerful tool for modelling heat and fluid transfer in, and the deformation of, complex shapes. The method achieves generality by allowing element definition to proceed to some extent without regard to the geometry of the problem. It is only after the elements are 'embedded' into the problem space that their geometry is set. This separation of element definition and general methods for solution of the global matrices suggests that the Finite Element Method can benefit from an object oriented structure. A more complex element can be created by inheriting properties from a simpler element and adding any specific behaviour. Thus elements can be designed to match specific problem requirements more easily. Much of the element's complexity is hidden from the rest of the program making overall development simpler. We present a prototype object oriented library for applying the Finite Element Method and analyse its general structure and its benefits. Finally, we present an example of its application to 2-dimensional heat transfer within a basin.

Introduction
Basin modelling is a process whereby exploration geologists investigate the hydrocarbon potential of a geological basin area. Oil and gas are produced when organic material is subjected to an elevated temperature over a sustained period of time. Once produced, hydrocarbons may migrate due to pressure gradients in the source rock to a new location in the basin, the reservoir. Basin modelling is a four fold process:Reconstruction of the basin geometry back through to the age that the sediments were deposited, (this involves determination of the structure at present day, removal and decompaction of the sediments to obtain the time-depth history of the sediments, and restoration of any blocks that may have moved along faults).
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Geophysical Applications of Parallel Computing
Authors: Daube François , Highnam Peter , Ullo John 
Published: December 2007

Abstract
All current high performance computing platforms utilize parallel processing technology, with system sizes ranging from less than ten to a few thousand powerful processors. Geophysical computational tasks are now almost invariably 3D, from the processing of 3D seismic surveys to the modeling of wireline logging measurements. This paper reviews the computational challenges presented by 3D geophysics and describes the results that we have achieved using highly parallel systems. Because 3D structures are inherently more complex than 2D structures, realizing the full benefits of high performance systems requires ever more sophisticated visualization and model construction tools. We briefly review work on employing highly parallel systems in support of such tasks.
An Innovative Data Modeling Methodology Applied to Petroleum Engineering Problems
Authors: Chalon Philippe , Karcher Bruno , Allen C. N. 
Published: December 2007

Abstract
An innovative approach to modeling exploration and production data was derived from using an advanced, ISO standard, information description language, EXPRESS. In addition architectural principles have been developed to provide a strong structure to integrate data relevant to all the numerous disciplines of exploration and production. As a result this model is about one tenth as voluminous as in a classical structure, and provides more flexibility and extensibility.
Global Networking: Implications for Petroleum Engineers
Authors: Bailey J. A. 
Published: December 2007

ABSTRACT
The current, rapid growth in the use of global networking promises to have an important impact on the way that all professionals, including petroleum engineers, do their work. Currently, this networking activity is embodied in a facility called the Internet. The Internet now consists of more than 1,000,000 computers (hosts), worldwide, connected by a variety of transmission media. Through this facility, professionals can communicate with colleagues by electronic mail, can have access to a massive collection of programs and data, can participate in special-interest discussion groups chosen from thousands available and may eventually receive many of their professional journals in an electronic form. It is the thesis of this paper that these resources will cause a qualitative change in the way petroleum engineers plan, organize and conduct their work. The Internet could even change the way petroleum companies structure their engineering organizations.
This paper examines the structure of the Internet, details the resources currently available through it and attempts to project the impact of global networking on the lives of working petroleum engineers.
An Improved Human Interface for Computer-Based Log Interpretation
Authors: Skolnakorn Jirapa , Morriss S. L. 
Published: December 2007

ABSTRACT
Information from well logs is invaluable to the oil industry. However, only a limited number of people are able to fully utilize their logs by applying modern analysis techniques. Part of the limitation stems from the difficulty in learning to use log analysis software. There are a number of features that would serve to improve the human interface of this software, such as treating log curves as mouse-selectable objects which can be copied and moved to other displays or other tracks using familiar "cut and paste" methods common to graphical interfaces now found on personal computers. Observations of university students in an advanced logging class using two commercially available computer-based log interpretation programs helped identify performance obstacles encountered by users with limited experience. An experimental interface design which incorporates a number of new features has been developed using an advanced object-oriented development environment, thus allowing a great deal of flexibility in implementing changes and adding new features based on feedback from actual users.
Rod Pumping Expert System
Authors: Martinez E. R. , Moreno W. J. , Castillo V. J. , Moreno J. A. 
Published: December 2007

ABSTRACT
This paper describes the development of a rod pumping expert system in which methods of emergent computation are extensively used. These methodologies include artificial neural networks (ANN) and genetic algorithms (GA). The system is implemented in order to provide assistance to the production engineer both in the problem diagnostic of operating units and the design of rod pumping facilities. The chosen computational methodologies prove to be very efficient in executing these tasks and require considerably less implementation time than other more common expert system methods.
The problem diagnostic method, implemented in the system, is based on the analysis of field dynamometer data by means of an ANN. These ANNs are computational tools, inspired on models of biological neural systems, with remarkable signal processing capabilities proven to be effective in areas such as pattern recognition and classification. The diagnostic task is achieved by using an ANN to analyze the down-hole pump cards and by means of its pattern recognition ability evaluate the condition of the pumping equipment. The ANN reacts to gross and subtle data features in the down-hole card and produces a response generalized from the "knowledge" stored in the network during a training process.
The facility design module of the expert system is implemented by means of a GA which executes an "intelligent" search in "pump configuration space" in order to produce automatically and fast several optimal design proposals compatible with the equipment restrictions and the "target" production entered by the user. Genetic algorithms (GA) are global search methods inspired in the principles of genetic evolution, which have been found to be very well suited for a multiparametric search in complex spaces. This outstanding search capability of GA is exploited in the configuration of rod pumping system designs based on the API RP 11L procedure. A run of the design procedure outputs several optimal configurations with the corresponding strokes per minute, plunger size, pumping speed, sucker rod type and operating characteristics.
Use of the expert system has proven to reduce the expertise required for problem diagnosis and design in rod pumping systems with considerable savings in the engineer man hours required by those tasks.
Document Management Systems: A Small Business Unit Implementation
Authors: Magstadt T. J. , Engler R. A. 
Published: December 2007

ABSTRACT
An outline of the requirements developed to select and implement an electronic document management system for a small business unit is presented. Emphasis is placed on the system installed and how that system is being used to provide a wide variety of data access services to managers, supervisors and staff. Integration of the system into a multi-platform, LAN environment with other more traditional database resources is also discussed.
Questions that will be addressed include: What are some of the key components which should be considered when embarking on an investigation of document management systems and their potential use in the petroleum industry?How do we provide data in a timely manner to the people who need that information to make decisions?What are some of the key issues which arise when implementing a document management system?
PC-Based Cement Job Design System Improves Primary Cement Jobs
Authors: Kulakofsky D. S. , Henry S. R. , Porter David 
Published: December 2007

ABSTRACT
Before the advent of graphical user interfaces (GUIs), cement job simulation programs were difficult to use, requiring large computer systems and occasionally yielding results that were difficult to understand. Often, the data input task was cumbersome enough to limit usage of these simulators. With the wide variety of today's Windows™*-based PC graphics packages, however, complicated results can be made understandable through visual displays. This paper describes a technically advanced, user-friendly, PC-based primary cement job design system that can use temperature-dependent rheology and Critical Reynolds Number when calculating frictional losses.
Flue Gas Generation Problems, Solutions and Cost - Block 31 Field
Authors: Caraway George E. , Lowery Leo L. 
Published: December 2007

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
This paper outlines the physical equipment and flow of the Atlantic Richfield et al 54 MMCF/D Flue Gas Plant located in the Block 31 Field, Crane County, Texas. Conservation of resources; water, natural gas and energy was incorporated in the initial design.
Corrosion has been of primary concern to the operator. The results of a program evaluating ammonia and filming amines to control corrosion are reported.
Operating information is submitted on staffing, mechanical and fouling problem, factors governing the manufacture of flue gas as a ratio to input fuel gas and dehydration.
A method to be utilized in estimating cost of any size flue gas plant is suggested.

Introduction
The world's largest flue gas operation is being conducted in the Block 31 Field, Crane County, Texas. This multi-pay field was initially discovered by The Atlantic Refining Company, now Atlantic Richfield Company, in November, 1945. Early in the field's life, the industry's first miscible displacement program was started in the Devonian reservoir. At the time the 54 MMCF/D flue gas plant started operations on March 8, 1966, the miscible program had been conducted for approximately seventeen years. Prior to construction of the flue gas plant, a conventional gasoline plant and injection facilities were in operation. By taking a portion of the absorber residue gas and burning in a controlled atmosphere the volume can be increased nine to eleven times. The economic attractiveness of such a procedure was the discontinuation of purchasing 30 to 40 MMCF/D of natural gas, release for sale of 20 to 30 MMCF/D of produced gas and the assurance of a continuing source of displacement medium for the reservoir. In addition, the flue gas plant will increase oil recovery from the field through an extension of the economic life of the injection program.

PROCESS DISCUSSION
A diagram of the overall processing scheme of the Block 31 facilities is shown in Figure 1. Feed stock for the flue gas plant is absorber residue gas and air.
Incorporated in the flue gas plant is a treating system for the absorber residue gas prior to its combustion in the flue gas generators. The processing objective of the treating plant is to reduce sulfur content to a minimum.
An Improved Design Equation for Tubular Collapse
Authors: Issa J. A. , Crawford D. S. 
Published: December 2007

Abstract
This paper presents a new equation for predicting the collapse of tubulars under external pressure. The development of the equation is based on a large number of non-linear finite element simulations of tubulars with different geometrical tolerances and mechanical properties. The simulation results for the collapse pressure and post-collapse geometry of the tubulars were verified with full scale physical tests. A nonlinear regression analysis was then performed on the data obtained from the simulations to optimize the parameters of the collapse equation. The new equation accounts for variations in the tubular diameter, wall thickness, ovality, eccentricity, and material elastic-plastic behavior.
This new collapse equation provides significant advantages over existing formulas, mainly because it was developed based on non-linear mechanics solutions of the collapse problem as compared to equations derived from statistical analysis. In addition, the equation gives the true collapse pressure of the tubular, whether the tubular collapses elastically or after it has yielded. The new equation could be used to design tubulars based on manufacturing tolerances with respect to wall thickness, ovality, and eccentricity as well as material mechanical properties. This allows for design optimization which could account for significant cost savings, especially when designing expensive non-API tubulars such as corrosion resistant alloy tubulars. The new collapse equation presented in this paper provides accurate predictions of the collapse pressure of tubulars and accounts for tolerances in the tubular geometry and material elastic-plastic behavior. This new equation is simple and could be used in optimizing tubular design.
Critical Mud Weight and Risk Contour Plots for Designing Inclined Wells
Authors: Tan C. P. , Willoughby D. R. 
Published: December 2007

Abstract
An analytical method, used as part of a study to develop an understanding of stress-induced wellbore instability in the North West Shelf of Australia, has been prepared as a suite of spreadsheets with macros to carry out drained and undrained stability analyses of inclined wells under a generalised plane strain condition. The contour plots of critical mud weight and failure extent produced by the spreadsheets can be used together with the mud weight stability profiles to select optimum wellbore alignment and to assist with mud weight and casing design.
Development and Application of a Mineral-Oil-Based Mud and Tracer for Low-Invasion Coring at the Point McIntyre Field
Authors: Bloys J. B. , Rathmell J. J. , Kriel W. A. , Spence A. P. , Wylie G. S. , Ray C. R. 
Published: December 2007

Abstract
Coring operations were conducted with a mineral oil based mud to obtain low invasion cores from the Kuparuk sandstone in the Point Mclntyre field on Alaska’s North Slope. These cores were taken to provide oil saturation, porosity, and permeability data for calculation of oil reserve ownership for the three major oil companies participating in the field. This paper describes the development, testing and application of a very low invasion, low water content, mineral oil based coring fluid. This fluid, in combination with specially designed low invasion coring bits and high penetration rates, consistently produced 4-inch cores with filtrate invasions limited to the outer 0.25 to 0.50 inches of the cores in sandstone with permeabilities ranging from a few millidarcies to greater than 1.0 Darcy. A new oil soluble tracer was identified, which when present at 30 parts per million could reliably quantify mud filtrate invasion.
Core-Based Horizontal or Highly Inclined Well Stability Analysis for Unconsolidated Formations
Authors: Morita Nobuo , Ross C. K. 
Published: December 2007

Abstract
The prediction of a safe mud weight is important when drilling highly inclined or horizontal wells through permeable, poorly consolidated formations. If the mud weight used to drill these types of wells is too high, differential sticking of the drill string will occur. If the mud weight is too low, it is possible that the well bore will collapse. The standard linear elasticity borehole stability analysis methods used by many in industry predicts an unnecessarily high mud weight to prevent borehole collapse, while the safe mud weight is significantly lower. This paper describes a new core-based well stability analysis for horizontal or highly inclined wells in weak formations. New procedures to measure core strength and deformation and the numerical procedure to calculate the well stability for a highly non-linear formation are discussed. Field data and experiences are also included to validate the non-linear borehole stability analysis.