bluuebunny/crossref_metadata_2025_split huggingface dataset:
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

Abstract
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

Abstract
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

Abstract
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

Abstract
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

Abstract
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

Abstract
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

Abstract
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

Abstract
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

Abstract
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

Abstract
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

ABSTRACT
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

Abstract
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

Abstract
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

Abstract
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

Abstract
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

Abstract
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

Abstract
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.