bluuebunny/crossref_metadata_2025 huggingface dataset:
Factors Affecting Proppant Flowback with Resin Coated Proppants
Authors: Almond S. W. , Penny G. S. , Conway M. W.
Published: December 2007

Resin coated proppants (RCP's) have been used to prevent proppant flowback for several years in the hydraulic fracturing of oil and gas wells. Proppant flowback problems, however, still exist with the commercially available RCP's and several operators report failures around the world under a variety of well conditions. To date, a clear explanation of the RCP failure mechanisms and the conditions under which failure occurs has not been presented in the industry.

A correlation between the unconfined compressive strength (UCS) of RCP materials and the proppant flowback potential has been previously presented by Vreeburg, et al11. This paper will present the results of a study on a variety of factors which effect the proppant flowback of a number of commercially available RCP materials. These factors include 1) the effect of fluid pH (7 to 12) and fluid type (KCL, seawater and a HPG/Borate fracturing fluid), 2) the effect of fluid/proppant slurry shear, 3) the effect of closure pressure during RCP curing, 4) the effect of stress cycling and 5) the effect of downhole flow conditions on proppant flowback.
New Breaker Technology for Fracturing High-Permeability Formations
Authors: Norman Lewis , Vitthal Sanjay , Terracina John
Published: December 2007

Regained permeability studies with HEC polymer in high-permeability cores revealed that persulfate-type oxidizing breaker and enzyme breaker do not adequately degrade the polymer. Use of high concentrations of acid or peroxide breakers did show improved breaking, but additional work is needed to apply high concentrations of these breakers properly. Sodium persulfate breaker was found to be thermally decomposed, and its decomposition was accelerated by formation minerals. Enzyme breaker adsorbed onto the formation, but still partly functioned as a breaker. Dynamic fluid-loss tests with reduced-pH, borate-crosslinked gels suggest that accelerated leakoff away from the wellbore could be obtained through the use of a delayed-release acid. Rheological measurements confirmed that a soluble delayed-release acid could be used to convert a borate-crosslinked fluid into a linear gel. This conversion was visually confirmed by tests involving a delayed-release acid and a borate-crosslinked fluid in a single-pass flow loop apparatus. Higher concentrations of breaker were placed in a borate-crosslinked fluid by encapsulating the breaker, and controlled viscosity reduction was obtained.

A simulation using a 3D commercial simulator showed improved cumulative oil production when increased fluid loss from a soluble delayed-release acid was applied.
Low Permeability Gas Reservoir Production Using Large Hydraulic Fractures
Authors: Holditch Stephen Allen , Morse R.A.
Published: December 2007

There has been relatively little work published on recovering hydrocarbon gas from published on recovering hydrocarbon gas from low permeability reservoirs. Recently several nuclear projects have explored the feasibility of creating a cavity and a fractured zone in such a formation to stimulate production. One such test, Gasbuggy, was begun Dec. 10, 1967, with the detonation of a 26-kt nuclear device in the Pictured Cliffs formation, Rio Arriba Co., N. M.

This paper presents a study of stimulating low permeability reservoirs by the creation of long hydraulic fractures. A two-dimensional, two-phase numerical model was used. The reservoir properties of the model approximated those published for the Pictured Cliffs formation. The situations simulated were both vertical and horizontal fractures extending up to 3,000 ft from the producing well. Also, a model simulating a nuclear cavity was designed. This model simulated a well containing an 80-ft radius cavity with a fractured zone of 100 times the reservoir permeability, extending 200 ft past the cavity. The situation simulated was for production with a constant wellbore pressure. Production rate and cumulative gas produced were monitored as functions of time. From these parameters an economic evaluation of each system was prepared. The results of this study showed that all fractures of greater than 1,000-ft radius had greater productivity and greater cumulative gas productivity and greater cumulative gas produced than did the nuclear cavity. It produced than did the nuclear cavity. It appears that large hydraulic fractures may provide an economic means of producing gas from provide an economic means of producing gas from very low permeability reservoirs.

Introduction

There are large quantities of known hydrocarbons in place that are not being produced because the formation containing the produced because the formation containing the oil or gas has a permeability too low to allow economic production rates. In order to produce this type reservoir, some form of stimulation is required. There has been relatively little information published on the stimulation of low permeability reservoirs. In the past few permeability reservoirs. In the past few years, some projects have been conducted concerning the application of contained nuclear explosions for increasing the productivity in tight formations. The purpose of nuclear stimulation has been to create a large cavity with a radial fractured zone extending past the cavity, or in effect increasing the radius of the wellbore.

Another stimulation method is hydraulic fracturing. The purpose of fracturing is usually to improve the formation capacity near the wellbore, offsetting the damage that occurred while drilling. However, another use of fractures presented by L. E. Wilsey provided the basis for this work. provided the basis for this work.
An Innovative Technique for Damage By-Pass in Gravel Packed Completions Using Tip Screen-Out Fracture Prepacks
Authors: Montagna James N. , Saucier R. J. , Kelly Pete
Published: December 2007

An innovative completion technique is being used in wells that require sand control to help eliminate high skins and increase pay, or effective kh, and thus improve well productivity. The success of this technique lies in concentrating high conductivity proppants in the near-wellbore region. This is accomplished by creating and propping a properly designed, length limited, hydraulically-induced fracture in conjunction with an annular water gravel pack. The result is a highly conductive flow path from virgin formation, through the near-wellbore damaged zone, and into the wellbore that also controls formation sand.

The limited fracture is designed with the intent of preserving the integrity of the near well gravel pack since this aspect is critical to realizing the full benefits of the fracture. Industry data indicates that optimum gravel packing is achieved with a brine proppant carrier. In some cases, the entire operation (limited fracture and gravel pack) may be completed with brine. However, in other cases, as discussed here, the high leak-off associated with brine is reduced by a product developed to overcome the excessive fluid leak-off. Brine following this material provides the carrier medium for proppant placement in the fracture and for the gravel pack.

The process is described and examples of field applications and results will be presented.
Specific Selection Criteria and Testing Protocol Optimize Reservoir Drill-in Fluid Design
Authors: Donovan Joseph P. , Jones Tom A.
Published: December 2007

Proper test and evaluation methodology for reservoir drill-in fluids is an important step in the construction design of a producing wellbore. Drill-in fluids are specifically designed to meet drilling and completion objectives, simplify reservoir cleanup and maximize production rates in open hole completions. New protocols developed by drilling fluid and completion laboratories have proven to be effective tools for evaluating fluid designs that optimize production.

Drill-in fluid selection begins with an initial screening process taking into account qualifying issues such as environmental acceptability, reservoir temperature, physical limitations, and chemical compatibility between the fluid and the reservoir. The final fluid formulation should minimize formation damage, fluid leak-off rates, breakout pressures, and wellbore cleanup of drill-in and completion operations, thus maximizing the productivity of the well.

Formation damage risks can be minimized if laboratory testing procedures parallel specific reservoir conditions. Case studies confirm that a methodology based on laboratory data that incorporates drilling fluid, completion, and workover operation protocols is effective in lowering completion costs and increasing production.
Prediction of Asphaltene Deposition During Production - Model description and Experimental Details
Authors: Takhar S. , Ravenscroft P. D. , Nicoll D. C. A.
Published: December 2007

Asphaltene deposition can arise during normal production causing formation damage, precipitation in tubing, difficulties in wireline operations, stuck valves and lost production.

Identifying which type of crudes will display this behaviour, prior to full production, enables the operator to make remedial plans.

A short description of a thermodynamic model to predict the onset parameters (temperature, pressure) will be described along with the essential experimental data required as input for subsequent modelling studies. This will be supported via model validation from real field data from two of BPX's North Sea fields.

A key conclusion of the findings is the ability to predict the deposition of asphaltenes downhole without the need for generating data from expensive single phase downhole samples.
Mechanisms of Formation Damage by Retention of Particles Suspended in Injection Water
Authors: Roque C. , Chauveteau G. , Renard M. , Thibault G. , Bouteca M. , Rochon J.
Published: December 2007

This paper reports the main results of an experimental study of the process of permeability impairment by particles suspended in injection water.

The experiments were carried out under well defined conditions both realistic and sufficiently well-known to yield clear and useful conclusions concerning actual retention mechanisms and their consequences for formation damage. Injection of waters containing particles of different sizes into sandstones of different permeabilities resulted in drastic permeability reductions, even for particles smaller than pore throats, with a very high flow rate sensitivity. The different possible steps in formation damage process have been characterized and related to phenomena at pore scale level. The results are analysed according to a new theory capable of predicting retention by two mechanisms for particles smaller than pore throats that do not absorb on pore walls without flow. This theory takes into account the competition between surface forces and hydrodynamic forces which can either induce or prevent retention depending on force balance at the location of capture.

All experimental observations agree with this theory which, therefore, provides a reliable basis for quantitative predictions of formation damage.
Modelling Fines Mobilization, Migration and Clogging
Authors: Wennberg Kjell Erik , Batrouni George , Hansen Alex
Published: December 2007

We introduce and discuss a model for fines mobilization, migration and clogging in porous media based on the convection-diffusion equation. Our model contains two fields: The concentration of fine particles deposited on the pore walls and the concentration of fines suspended in the ambient liquid. The model contains four parameters - or seven if certain non-linearities in the clogging process are important. We discuss the physical contents of the model and test it numerically in two dimensions.
Factors to Consider in the Effective Management and Control of Fines Migration in High Permeability Sands
Authors: Oyeneyin M. B. , Peden J. M. , Hosseini Ali , Ren G.
Published: December 2007

In recent times, the oil industry has shown increasing awareness towards the maintenance of optimum well productivity through better drilling/completion practices. Attempts are being made to control the invasion of high permeability sands by mad solids through the use of sized Loss Control Materials(LCM) which can be difficult to clean up. Recent developments involve the use of sized carbonate and sized salt systems with mixed results. Whilst these special systems have been known to provide efficient fluid loss control, the cleanup efficiency especially in horizontal wells has been known to be poor in certain instances. Likewise, the completion of long horizontal sections through highly permeable, unconsolidated reservoirs has witnessed increasing use of prepacked screens many of which are reported to be plugged/damaged by filter cake debris and completion fluid solids as well as formation fines. Gravelpacks are also known to have been damaged not only by formation fines but also by solids in completion fluids injected from the wellbore especially during cleanup operations.

The migration of sized particles in the drilling and completion fluids through high permeability reservoir sands, prepacks or gravelpacks is characterised by flow capacity decline which may be instantaneous or gradual depending on the migration process and the pore bridging phenomena. Therefore, accurate prediction of the prevailing pore blocking mechanism for a given pore throat-particle size relationship can provide a good basis for the estimation of the maximum allowable size of particles in various completion fluid systems and also provide a good guide to the design for optimum prepack and gravelpack performance through the use of properly sized gravels.

In this paper, attempts have been made to analyse the impact of a number of key parameters on productivity impairment. The analysis has been based on the results of in-depth research into particle-pore bridging phenomena. Based on rigorous experimental studies to define the phenomena, a number of deterministic models have been developed to mathematically define the unconsolidated pay sand/pack sand systems permeability decline profile as a function of invasion pattern, migration/pore blocking mechanism, production /injection rate, production time and fines concentration and fines textural properties. Application of the results to the optimisation of drilling/completion fluids design as well as prepack/gravelpack design and analysis are illustrated with specific case studies.
Quantifying the Factors Influencing Gravel Placement and Productivity of an Internally Gravel Packed Completion based on Field Data Analysis
Authors: Welling Rudy W. F. , Jonathan Philip , Reijnen Paul H. F. , Samuel Allan J.
Published: December 2007

A detailed analysis of 341 internally gravel-packed zones in wells from three oil fields was carried out to determine which parameters significantly influence the placement of the gravel in such a completion and the well's resulting productivity.

The database analysis demonstrates that, in addition to the well-known impairing factors, such as dirty completion fluids and viscous fluid-loss control pills, the performance of gravel packs can be improved by increasing the number of perforations—especially in 7" completions. This suggests that the perforation tunnel is the most critical area in an internally gravel-packed completion.
Use of a Solids-free Viscous Carrying Fluid in Fracturing Applications: An Economic and Productivity Comparison in Shallow Completions
Authors: Stewart B. R. , Mullen M. E. , Howard W. J. , Norman W. D.
Published: December 2007

The paper presents the findings of 20 completions in both oil and gas wells. These completions were performed from the period of 1973 through 1994. The early completions employed sand control technology of the 1970's and 1980's with most requiring acid stimulation immediately after sand placement to assure the removal of completion damage. The 1994 completions involved fracturing combined with sand control (frac-packing) in the same reservoirs which had been gravel packed in the ‘70's and ‘80's.

The unique aspect of this review is that these fracturing treatments were carried out using a solids-free viscoelastic surfactant fluid. The fluid system is discussed along with the reasons why this particular fluid was selected. The implications that this fluid has on the fracture placement as well as productivity are discussed.

Laboratory testing indicates that the solids based polymer fluids actually exhibit "deep bed" filtration and plug the formation pore throats, the fracture packs, and perforations. This damage can require acid stimulation for optimized production. The completion results are compared by use of a productivity index (J), normalized J14, and bottom hole pressure build-up analysis.
Frac and Pack Stimulation: Application and Field Experience from Hylia Gabon, West Africa
Authors: Petit G. , Leschi P. , Dusterhoft R.
Published: December 2007

This paper describes a two-step frac/gravel pack completion procedure conducted from a jack-up rig offshore Gabon in 1993 and 1994. After an in-depth, sand production study, seven wells were completed using hydraulic fracturing and cased-hole gravel packs.

Because the Anguille formation spreads over a large gross interval, production screens of 50 to 100 m in length were used. Single-stage internal gravel packs (IGPs) on such large intervals were considered impossible to achieve with reasonable skin values.

The frac-pack technique was an attractive way to achieve good proppant placement, considering that the formation being fractured would have a more homogeneous conductivity across the whole zone and a uniform proppant placement would be achieved in the perforations as well as in the annulus.

High-efficiency frac gel using cross-linked HPG and a low damage one using HEC were compared to determine the best fluid to be used for these completions. Bottom hole pressures during treatment operations, as well as post-treatment pressure build-ups from each well, were analyzed in order to make general recommendations on this hydraulic fracture design.
A Comparison of Different Types of Blocking Agents
Authors: Seright R. S. , Liang J.
Published: December 2007

Many different materials have been proposed to reduce channeling of fluids through fractures and streaks of very high permeability. These materials include gels, particulates, precipitates, microorganisms, foams and emulsions, In this paper, we compare the placement and permeability reduction properties of these different types of blocking agents. Comparisons were made of their selectivity in entering high-permeability rock in preference to low-permeability rock. We also examined their ability to reduce permeability to a greater extent in high-permeability, water-saturated zones than in low-permeability, oil-saturated zones. Concepts are identified that may lead to blocking agents with placement and/or permeability-reduction properties that are superior to those of gels.
Acid Diversion from an Undamaged to a Damaged Core Using Multiple Foam Slugs
Authors: Behenna F. R.
Published: December 2007

Parallel-core flow tests were conducted with two undamaged core plugs having widely contrasting permeabilities. Tests showed that essentially no diversion of liquid to the low-permeability core would be realized following injection of a foam slug, unless specific permeability conditions were met. Tests also indicated that gas trapping during liquid injection following a foam slug is much more efficient in low-permeability cores than in high-permeability cores. Trapping of foam caused the total mobility (λt) in the low-permeability core to remain low during liquid injection, while λt in the high-permeability core increased greatly. In one test, this effect caused complete shutoff of liquid flow to the low-permeability core after a small foam slug was injected.

In other tests, a small foam slug was followed by injections of unfoamed acid into a damaged and an undamaged sandstone core. The results indicate that the combined effect of the foam slug and acid was extremely effective in diverting acid flow from the undamaged core to the damaged core. Long core plugs of similar permeability were used. A thin, low-permeability core wafer was placed at the core face of one of the plugs to simulate near-wellbore damage. This thin damage layer caused highly uneven liquid flow to the two cores before foam slug injection. The acid diverted to the damaged core caused a rapid increase in the permeability of the damaged zone. Sustained diversion of liquid flow to the damaged core was then maintained. Injection of a second foam slug caused the liquid flow distribution to the cores to nearly equalize, since trapped gas reduced liquid mobility in both cores. The liquid flow distribution then diverged as mobility in the cores increased at unequal rates.

The bottomhole pressure (BHP) response from a matrix acidizing treatment using foam slugs for diversion illustrates the agreement of field results with laboratory results.
Chemical System for Treating Formation Damage Induced by Inverted Oil Muds
Authors: Ventresca M. L. , Betancourt J. , Castillo J. , Cigüela S. , Azuaje C.
Published: December 2007

Inverted oil muds have the ability to control the expansion of water-sensitive clays, and they must be used whenever wellbore stability is unattainable with water-based muds. However, the initial production rate of a well drilled with inverted oil mud is often lower than expected.

The prevalent damage mechanisms have been found to be: Inversion of wettability of the rock matrix from water-wet to oil-wet, and formation of stable emulsions inside the porous medium. Reductions to the mobility of oil between 60 % and 98 % have been found.

A process, with the trade name ULTRAMIX™ was developed which includes a mixture of surfactants and solvents, each one having a specific function against the effects of the components of the inverted oil mud filtrate, and a procedure for the proper placement of this mixture in the porous medium surrounding the wellbore.

Laboratory tests of this process showed a damage removal up to 96 %. Full scale field treatments conducted over 5 years yielded production increases ranging from 60 to 300 %, sustained over long periods.
An Overview of Underbalanced Drilling Applications in Canada
Authors: Falk Kelly , McDonald Craig
Published: December 2007

Underbalanced drilling is quickly becoming an important technology in the Canadian oil and gas sector. While drilling impairment has always been a concern, a significant increase in horizontal completions has brought this issue to the forefront. A number of stimulation techniques are available for overcoming impairment in vertical wells or shallow damage in horizontal wells, however, deeper matrix damage is often difficult to remove in long horizontal sections. With this in mind, Canadian producers have looked to underbalanced drilling to prevent damage caused by fluid leak-off and fines migration.

Many of the oil and gas fields in Canada are subhydrostatic, therefore underbalanced drilling operations often require the entrainment of a gas phase in the drilling fluid to generate the appropriate bottomhole pressures. In most cases, because of safety concerns, nitrogen gas is used.

Two basic styles of nitrified underbalanced drilling are currently used with conventional rig drilling operations. One involves injecting nitrogen at the standpipe to co-mingle with the drilling fluid. The other, referred to as parasite injection, utilizes an external gas injection conduit that allows gasification of the drilling fluid in the vertical annulus. Either approach has specific advantages which must be considered for each application.

An essential component of underbalanced drilling (UBD) success is effective two-phase flow modeling. Initial simulation is required to investigate and optimize various design options in the planning stage.

This is often followed up by providing onsite support to assess actual job parameters and make any required design modifications.

This paper focuses on these two UBD techniques, addressing the advantages and limitations of each. Two-phase flow analysis and job design will be discussed. A summary of the jobs completed, operational details and production results will be given.
Field Application of a New Cleanable and Damage Tolerant Downhole Screen
Authors: Scott Lester G. , Malbrel Christophe A. , Whitlock Michael B.
Published: December 2007

This paper describes an alternative technology to conventional wire wrapped and prepacked screens. In this new screen, multiple and independent layers of a permeable stainless steel composite material are sandwiched between a perforated base pipe and an external armored cage.

Advantages of this design include: 1) even extreme mechanical deformations do not affect the screen's sand retention; 2) an all-metallic construction eliminates the deficiencies common to prepacked screens (loose sand packing, eccentric prepack annulus, chemical incompatibilities with resin coatings, cracking of resin coated prepacks); 3) its compact construction results in a small OD that extends its range down to small diameters for through tubing gravel packs and gravel pack repairs.

These advantages have been substantiated by laboratory tests and field installations. The results of these tests are presented in this paper.
Integrated Drilling System
Authors: Tonnesen Harald A. , Berg Brit , Kvalvaag Tore , Pedersen Sigbjorn
Published: December 2007

The Integrated Drilling System (IDS) is based on a computer network that interconnects all drilling machinery and sensors to a distributed supervisory and control concept. This has been used to implement automated operations and full remote control from a central control room, with multimedia technology utilised for the man-machine interface.
Gas Systems Analysis Model - Technology and Policy Assessment of North American Natural Gas Potential
Authors: Becker Alan , Godec Michael , Pepper William , Zammerilli Anthony
Published: December 2007

Alan, Becker, Michael godec, William Pepper, and Anthony Zammerilli

Integrated national-level evaluation of North American natural gas supplies and markets has traditionally been compromised by lack of adequate data and the need to simplify the modeling methodology. The availability of more comprehensive and specific data on the domestic gas resource, combined with the continued evolution of high- speed computing capability to cost-effectively analyze this information, has provided the needed impetus to develop more sophisticated modeling capability to assess specific technology and policy impacts on the U.S. natural gas market.

The paper presents an overview of the Gas Systems Analysis Model (GSAM), which has recently been developed by the U.S. Department of Energy (DOE) to assist federal R&D planners and policy analysts. GSAM is a comprehensive, market-driven planning tool which can be cost-effectively tailored to assess economic, technology, and strategic facets of gas market planning from the specific reservoir setting to the unique end-user situation. The disaggregated supply assessment approach developed for GSAM, with the individual reservoir as the basic unit of analysis, provides the details needed for comprehensive technology assessment, R&D planning, and policy analysis, consistent with an evolving North American natural gas market.

BACKGROUND AN

Introduction

The North American gas marketplace is rapidly evolving. Most forecasters believe the future growth of gas prices will be relatively modest. The historical surplus of gas deliverability has ended, new markets for gas are forming, and open access transportation is changing the way gas gets to market and the costs associated with getting it there. At the same time, the characteristics of U.S. gas supplies are changing. Environmental and economic pressures are increasing the need for expanding gas supplies. The primary source of U.S. gas reserve additions has shifted from new discoveries to the more extensive development of known resources, which will continue to come from increasingly more complex and technically challenging settings. Consequently, the U.S. must expand its sources of low-cost gas supplies, and technology will play a key role in achieving this expansion.

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An Integrated Engineering/Geoscience Desktop
Authors: Thomas L. K. , Evans C. E. , Todd B. J.
Published: December 2007

This paper presents the development of an Integrated Engineering/Geoscience Desktop and a description of the software available for evaluation and development of hydrocarbon prospects, from basin-wide studies down to specific reservoir targets. The Desktop was built using Landmark's data model, with POSC-compliant extensions to build an Engineering/Geoscience project database. Software for populating the project database from corporate databases was also developed and is described in detail. Phillips petroleum engineering software was then integrated with geoscience software, sharing data and results in a seamless computing environment.
Modelling Sandstone Acidizing by Image Processing
Authors: Gao Y. , Sharma M. M.
Published: December 2007

The reactivity of acid with rock in an acidizing process depends on the abundance and the geometrical arrangement of various minerals with respect to each other. A model is developed to compute the rate of acid consumption and the change in rock porosity as a function of time. The minerals are located in accordance with thin section images. Under specified reaction kinetics, real time simulation of mineral dissolution is conducted graphically on a computer. Since the rate of reaction of each mineral is known, an erosion process is used to update the image of the rock as a function of time. This procedure can be recorded by a series of images and the porosity, permeability and cumulative acid consumption can be computed. It is shown that this model can provide substantially different results than a simple model that is based only on -the mineral abundance in the rock matrix. In some cases this can have a significant impact on acidizing simulators that are currently used. Such simulators do not use petrographic information on the relative location of minerals in modelling acid consumption rates.
Well Completions Accurately Designed with Computer Support
Authors: Monti Maurizio , Marangoni Marco , Aliverti Eleonora , Cerruti Sergio , Fanciulli Roberto
Published: December 2007

This paper presents a knowledge based system developed to support the completion engineer during the process of well completion design. WELCOME (WellCompletion Engineering) enforces a standard completion design procedure which improves safety and operational. aspects of completion activities. The system explains and justifies the approach to follow during the design by means of on-line manuals and references, and provides a full integration of commonly used computational packages. WELCOME relies on several advanced computer technologies, such as object orientation, knowledge based and hypertextual interaction to provide the user with a rich and friendly work environment. After a preliminary test phase, the system has been delivered to headquarters and operating Districts where it is routinely used.
Unplugging the Mainframe: Moving Production Systems to Client-Server
Authors: Christie George W. , Balcom Marni L.
Published: December 2007

In the fall of 1994, Chevron Canada Resources (CCR) retired its mainframe computer in favour of a distributed desktop computing environment. While the accounting applications were moving to a different mainframe in San Ramone, all the production department's applications needed to be switched to client-server. The deadline was set as September 25, 1994 to unplug the mainframe so the installation had to be complete or functionality would be lost.

Only a month behind schedule, the production department's switch to client-server was complete and the functionality of the system had been improved.

Customers pushed for the project by demanding a move to PCs and workstations. The key drivers were an effective Graphical User Interface (GUI), greater availability of software and an open systems architecture. The estimated cost savings to Chevron for maintaining only one computer system in-house, as opposed to both the desktop and mainframe solutions, is one million dollars a year.

Merak Projects, a software vendor, worked with Chevron Canada Resources to provide users with unlimited access to data and simple analysis tools for the desktop. HELIOS, a product developed by Merak, was used to integrate the many diverse applications and data sources within the organization. The Chevron system design was based on a central data warehouse on Oracle that had incorporated the Public Petroleum Data Model (PPDM). The data warehouse was made available to all those using HELIOS and Merak's Transport Manager, an application that moves data between data sources and applications. On the desktops were Merak's MAP, FORECAST and WellView™ products.

This paper will detail the justification for eliminating the mainframe, the architecture used in the system design, the transition process and the future direction of the project.
What Strategy for a Technical Drilling Information System?
Authors: Dumont J.
Published: December 2007

Most of the companies spend considerable time and effort in developing, implementing an adequate Information Technology System. For all of them, the questions are always the same: What's the strategy and the what's method for implementation ?

This paper describes TOTAL's project team strategy for applying Computer Technology to Drilling/Completion operations and the rapid development and installation in the operating affiliates (subsidiaries) of the new drilling system adopted by TOTAL.

This new system based on TOTAL's world wide drilling environment is thoroughly described, The business requirement specifications and the development, based on TOTAL's valuable past experience and the use of new tools, concepts and procedures, are also discussed.

This paper gives the method and solution adopted regarding the platform, data system management, engineering software's and Information Technology Organisation.

Finally, the keys to successful implementation in the Paris Head Quarters (HQ) and in the subsidiaries are included.
An Interactive Drilling Simulator for Teaching and Research
Authors: Cooper George A , Cooper Alexander G , Bihn Gregory
Published: December 2007

An interactive program has been constructed that allows a student or engineer to simulate the drilling of an oil well, and to optimize the drilling process by comparing different drilling plans.

The program operates in a very user-friendly way, with emphasis on menu and button-driven commands. The simulator may be run either as a training program, with exercises that illustrate various features of the drilling process, as a game, in which a student is set a challenge to drill a well with minimum cost or time under constraints set by an instructor, or as a simulator of a real situation to investigate the merit of different drilling strategies.

It has three main parts, a Lithology Editor, a Settings Editor and the simulation program itself. The Lithology Editor allows the student, instructor or engineer to build a real or imaginary sequence of rock layers, each characterized by its mineralogy, drilling and log responses. The Settings Editor allows the definition of all the operational parameters, ranging from the drilling and wear rates of particular bits in specified rocks to the costs of different procedures. The simulator itself contains an algorithm that determines rate of penetration and rate of wear of the bit as drilling continues. It also determines whether the well kicks or fractures, and assigns various other "accident" conditions. During operation, a depth vs. time curve is displayed, together with a "mud log" showing the rock layers penetrated. If desired, the well may be "logged", casings may be set and pore and fracture pressure gradients may be displayed. During drilling, the total time and cost are shown, together with cost per foot in total and for the current bit run.

A demonstration version of the program is available on the World Wide Web at the Berkeley Petroleum Engineering Page. Its current address is: msel6.mse.berkeley.edu
Using MS Visual Basic to Write Engineering Applications
Authors: Torres Donaldo E. , Anders Joseph L.
Published: December 2007

Microsoft Visual Basic for Windows (VB) allows Engineers to develop engineering applications that run in the Windows environment. VB provides the engineer a programming tool to write simple programs quickly that meet their needs. It is relatively easy to learn and use. Development of a Windows-like user interface is easy to do and there is a growing base of users and add-in applications.

The technological advances that have allowed engineering workstations to convert from a mainframe environment to a stand alone PC connected to a network have also provided new programming tools. Modern programming languages allow the programmer to quickly design screen panels and easily reuse code. This paper discusses the features available in VB and provides several program examples. Example programs written using VB include gas and oil fluid correlations, interpolation software, gas well bottom hole pressure from surface conditions, volumetric reserve calculations, simple log analysis, water pattern analysis and bottom hole pressure analysis. These applications were developed with Visual Basic version 3.0 Professional.
Economics of Damage Removal and Production Enhancement
Authors: Daneshy Ali
Published: December 2007

Beyond the ongoing major structural changes and cost savings resulting from the industry focus on increasing operational efficiencies, better technology holds the key to future reductions in the production cost of oil and gas. Achieving optimum productivity is a major component of this technology.

In the past most of the technical and operational aspects of production enhancement were keyed towards making reservoirs economically viable. This limited the application of such operations mostly to low permeability reservoirs, or when there was a drastic reduction in production rates. With the real price of oil steadily declining this need is continually extending towards higher permeabilities.

With focus on getting best return on investment it is no more enough to just be profitable. Optimum well productivity will enhance the economic value of any reservoir!! This paper will examine the economic impact of damage removal and production enhancement on reservoirs generally viewed to be high permeability.
Productivity Improvement by Frontier Horizontal Drilling in Italy
Authors: Schenato Adelmo
Published: December 2007

Italian domestic activity on horizontal wells has been specially addressed to carbonate reservoir and specifically targeted to re-entry in existing wells.

The speech will focus on the specific experience matured in frontier applications in Italy, from 1989 with the short radius drain holes in Sicily, throughout world record deep water short radius in the southern part of Adriatic sea and depth world record medium radius in a HP/HT reservoir in the Po Valley.

Production results will be reported as well as the achieved technological aspects.
Market Outlook For Athabasca Bitumen--The Economics of Location
Authors: Anderson B. S. , Chambers J. I. , McMurray D. R.
Published: December 2007

In situ bitumen production in the Athabasca Oil Sands Area in Northern Alberta, Canada, is well-positioned to make inroads into traditional markets for Canadian crude oil in Canada and in particular in the U.S. The development of the steam assisted gravity drainage (SAGD) technology has lowered supply costs and has made Athabasca bitumen competitive with other North American supply sources of heavy crudes and bitumens.

As part of a larger SAGD commercialization study, this paper examines potential markets for Athabasca bitumen, determines transportation options and costs to markets, and determines bitumen netback prices at the Athabasca Oil Sands Area resulting from sales to various markets.

The paper also examines how the current lack of pipeline infrastructure, out of the Athabasca Oil Sands Area, limits the market opportunity of Athabasca bitumen.
Mapping Temperature with Geostatistics Can Help Identify Steam-Chest and Optimize Oil Production
Authors: Yang An-Ping
Published: December 2007

As oil fields are being developed under difficult economical conditions, it becomes a matter of survival to be able to produce more oil with lower cost. In thermal recovery, one of the most important issues is the efficient use of steam injection. Temperature wells are used to measure the reservoir temperature. Geostatistical tools can be applied to these measurements to map reservoir temperature in a cross-section view or as a threedimensional volume for different time. This can help identify the steam-chest or hot-water region. When sand-zones are mapped and combined with the temperature map, cold regions in the sands can be located. The results can be used to estimate how much heat is in the reservoir and how much oil is remaining and where.

Geostatistical mapping has two advantages over conventional mapping. One is the geological concept of spatial continuity. Spatial continuity may be different in form and different for different direction and location. This offers flexibility and higher accuracy in the results. The other advantage is that geostatistical mapping can honor statistical distribution of the data. For example in the case of temperature, the lowest temperature and the highest temperature are usually limited and geostatistical mapping can honor these limits. Because temperature observation wells are usually far apart, geostatistical mapping can making full use of all information available to produce the best possible map.

Examples from the Kern River Field in California show how geostatistical mapping can be easily applied. A computer software on the PC is sufficient to do the job without additional cost. The results help the engineer optimize the thermal recovery operation.
Reservoir Monitoring And Evaluating On PTT Barat-Laut Structure As Part Of Reservoir Management Process
Authors: Briantoro Cecep , Tangkalalo Darwin , Soewono Soewono
Published: December 2007

The two important things in Reservoir Management Process are monitoring and evaluating. This paper will describe application of both steps on PTT Barat-laut structure.

PTT Barat-laut is one of hydrocarbon producing structures in Pangkalansusu field. Study on this structure is performed through several technical approaches, which are continuous monitoring on production well performance, well testing analysis, and 3-D seismic interpretation, for reservoir modelling.

An unique phenomenon is shown by the result of Pressure Build Up test which has been taken from several wells, providing layer or fracture indication in reservoir of PTT Barat-laut structure.

The other monitoring that occurs from production performance shows an anomaly on its decline rate, reaching 85–95 %/well/year.

3-D Seismic analysis on this structure shows several anomalies on its lines. "High amplitude" characteristic anomalies on 860 and 910 zones (the productive zones) refer some faults presence, and very strong "bright spot" performances have provided an indication of hydrocarbon accumulation in this structure.

By utilizing the techniques above can be obtained a global illustration of reservoir and geological characteristics of the structure. Further more, they will provide more realistic development idea.
Carbon Isotope Characterization of Migrating Gas in the Heavy Oil Fields of Alberta, Canada
Authors: Rich K. , Muehlenbachs K. , Uhrich K. , Greenwood G.
Published: December 2007

The development of Western Canada's oil and gas reservoirs has resulted in a proliferation of wells. Many of these wells exhibit gas migration to surface. This migration occurs at rates between 0.01 and 200 m3/day and is of obvious industrial and public concern. Thus far, attempts to eliminate gas migration have been expensive and relatively unsuccessful as the problem is not yet well understood. Identifying the origin of the gas will improve the economics and the effectiveness of remedial measures. The isotopic composition of gases can reveal their origin and help determine the source of the migrating gas.

Both the production horizon gases and the migrating gas in the Lindbergh-Lloydminster oil fields are predominantly (>96%) methane with trace components of higher hydrocarbons. Despite the lack of chemical differentiation, the gases possess unique carbon isotopic signatures. The methane of the production gases is very depleted in 13C (δ13C(PDB) ≈ −68 ‰), indicative of a bacterial origin. The trace ethane, propane and butane components of the Manville Group production gases are relatively enriched in 13C (δ13C ≈ −27‰, −18‰ and −20‰, respectively), and often the partitioning of 13C/12C between propane and butane is reversed compared to that of thermogenic gas, possibly the result of extensive biodegradation of these higher hydrocarbons. The source of the gas associated with the heavy oil field of the Lindbergh and Lloydminster regions is predominantly bacteriogenic, variably mixed with biodegraded thermogenic gas. Wherever sampled, the migrating gas was tagged by a δ13C ≈ −44‰ ethane. Such a signature is seen in the gases of the overlying Upper Cretaceous strata. The isotopic data suggest that the migrating gas is sourced from the shallow Fish Scales, White Speckled and perhaps the Lea Park Formations. Remedial efforts should therefore concentrate on Fish Scales and Second White Speckled shales.
Horizontal Well Sand Cleanouts
Authors: Heinrichs B. D. , Dedora G.
Published: December 2007

This paper discusses sand problems occurring in Horizontal Wells located in NE Alberta and NW Saskatchewan, Western Canada. These wells are completed in the heavy oil sands at 450–750 m TVD. Typical completions utilize 0.625 mm (0.025 in.) slots in liners 500m to 1200m long. The average length is approximately 900m. Some of the horizontal wells were initially very prolific at oil rates up to 70 m3/day (450 bbl/day) with no indication of sand problems. As depletion occurred, most of the wells only experienced one incident of a sand-plugging problem requiring an expensive cleanout in the horizontal liner section. The wells required more than one sand cleanout in the build section of the intermediate casing but these were relatively inexpensive. Many innovative improvements, techniques and even complete systems designed specifically for horizontal sand cleanouts have been developed in just a few years.