bluuebunny/crossref_metadata_2025_split huggingface dataset:
Parallel Unstructured Solver Methods for Complex Giant Reservoir Simulation
Authors: Fung Larry S. K. , Dogru Ali H. 
Published: December 2007

Abstract
The major issues for parallel solver in a modern reservoir simulator are robustness, scalability, efficiency, and flexibility. There is significant interest in running fast field-scale simulation for complex giant Middle-East reservoirs which will require tens to hundreds of millions of grid cells to give reasonable resolution. At the same time, significant geologic complexity will require the treatment of dual permeability regions, faulting and fractures, and high variations of reservoir and fluid properties. Of course, the methods should also work well for extracted sector simulation with local grid refinements in both the structured and unstructured discretization. The preconditioning methods considered in this work include both the single-stage and multistage frameworks. In the single-stage framework, a novel method in addition to the well-known variants of incomplete LU factorizations [ILU0, ILU(k), and ILUT] is considered. The new method is a highly parallel method which in this paper will be referred to as the unstructured line solve power series (LSPS) method. The method will be discussed and contrasted in light of key issues for parallel linear solvers. The unstructured LSPS has certain interesting properties in the parallel construct which makes it a highly effective component.
The multistage method researched in this work is of the constraint pressure residual (CPR) framework. The method uses approximate pressure solve as the first stage preconditioning to the full system preconditioning. A number of original adaptations based on this concept were researched. Here, the use of the parallel algebraic multigrid (AMG) method and other single-level methods mentioned above in combinations within the multistage CPR framework were explored. Certain methods constructed in this way are found to be highly efficient, scalable, and robust. The methods developed will be discussed and several test problems included in this paper.
A New Technical Standard Procedure to Measure stimulation and Gravelpack Fluid Leakoff under Static Conditions
Authors: Asadi M. , Penny G. S. , Ainley B. R. , Archacki D. J. , Bas van der F. , Bern P. A. , Brannon H. D. , Cobianco S. , Ghalambor A. , McElfresh P. M. , Milton-Tayler D. , Parker M. A. , Shah S. 
Published: December 2007

Abstract
A group of industry experts have compiled their years of experiences in developing a new technical standard to measure stimulation and gravel-pack fluid leakoff under static conditions. This method details step-by-step procedure for making fluids and measuring leakoff under static conditions. Stimulation and gravel-pack fluids are defined for the purpose of this technical standard as fluids used to enhance production from oil and gas wells by fracturing or acidizing and fluids used to place filtration media to control formation sand production from oil and gas wells, respectively. The procedure considers filter paper medium, natural core and synthetic core as the three filtering options. The paper also includes step-by-step example calculations of viscosity controlled leakoff coefficient and wall building coefficient.
How To Move From Excellent to Extraordinary Safety
Authors: Russell Larry 
Published: December 2007

Abstract
Excellent safety performance protects an organization's employees and assets. Extraordinary safety performance leverages excellent safety to create a high-functioning organization. Why is it that some companies can achieve the first level of performance but not be able to move toward the second? What does extraordinary safety performance really take and what can organizations do to get there? Finally, how does best-in-class safety correlate to high-performance in other areas?
Conventionally, the solution to accelerating safety performance has been to add to the existing infrastructure. Our experience of the past 20 years, however, has shown us that this approach can be counterproductive. Many large companies and corporations are already "swimming" in safety processes and systems. These organizations benefit not so much from adding assets but rather from learning how to strategically leverage the ones they already have.
Safety, because of its intrinsic value, is an ideal medium for improving overall organizational culture. Extraordinary safety performance is related to an organization's ability not just to maintain a healthy work environment and avoid serious events such as fatalities, but also to its ability to sustain performance at a world-class level across the board.
This talk examines the differences between excellent and extraordinary safety and presents ways that organizations can move toward best-in-class safety and organizational performance. This talk also covers the importance of creating extraordinary safety performance, its implications for organizations, and principles that make it possible.
The 200th Horizontal Openhole Gravel-Packing Operation in Campos Basin: A Milestone in the History of Petrobras Completion Practices in Ultradeep Waters
Authors: Marques L. C. C. , Paixão L. C. A. , Barbosa V. P. , Martins M. O. , Calderon A. , Pedroso C. A. , Fernandes L. H. C. , Melo J. A. , Chagas C. M. , Denadai N. J. 
Published: December 2007

Abstract
The paper presents an overview of the evolution of Petrobras open hole gravel packing operational practices after the 200th well has been successfully completed with this technique in Campos Basin (CB): a milestone in the history of Petrobras completion practices in deep and ultra-deepwaters.
The paper also presents a comprehensive description of the main steps taken to improve our horizontal open-hole gravel packing (HOHGP) practices towards a best-in-class status in unconsolidated oil-bearing turbidites. Since the first HOHGP job done in 1988 we had to move progressively from shallow to ultra-deepwater completion scenarios. Along this path a series of innovations has been incorporated to our sand face completion practices due to the ever-growing-complexity of the wells geometry, longer intervals to be completed, heavier oil reserves to be developed, rock mechanics restraints (ever-lowering fracture gradients) and the necessity of damage-free-, high-performance-wells to cope with the skyrocketing capital expenditures which is a general rule for offshore ultra-deepwaters nowadays.
Petrobras strategy conceived to continuously enhance its HOHGP completion efficiency index encompasses, the following interrelated subjects: -a comprehensive long-term plan to deal with the problem, -a multi-disciplinary team-work approach, -a strong cooperation with gravel packing tools & screens suppliers, -improvement of operational procedures and guidelines against which to measure well performance and -research & investment in cutting-edge technologies.
Discussions on the challenges envisioned for HOHGP operations in ultra-deepwaters in the years to come are also presented.
Application of Pressure-Transient and Production-Data Analysis for Hydraulic-Fracture-Treatment Evaluation
Authors: Economides Michael J. , Ehlig-Economides Christine A. , Tosic Slavko 
Published: December 2007

Abstract
The Unified Fracture Design (UFD) concept provides a mechanism to determine the optimal hydraulic fracture design for a given amount of a selected proppant, while modern hydraulic fracture treatment execution offers the potential to achieve the optimal design. The proppant number is a ratio of the proppant permeability and proppant volume product to the formation permeability and reservoir volume product. The cost of the hydraulic fracture treatment is directly related to the quality and quantity of proppant injected and successful achievement of the optimal fracture treatment easily offsets this cost when appropriate economics and physical and logistical constraints are considered in the job design. Pressure transient and production data analyses are described in terms of fracture length and conductivity and do not address parameters important to the UFD evaluation. A previous paper described the use of post-treatment analysis to evaluate the effectiveness of the treatment in terms of dimensionless productivity index, dimensionless fracture conductivity, and the proppant number.
With more and more permanent gauge installations, opportunities for pressure buildup analysis may occur under normal operating conditions without a specific test design. In this case both pressure transient and production data analysis may be available. The analysis addresses both single-phase oil and gas primary production and oil production under pressure maintenance or waterflood. Also, non-ideal fractures with height growth beyond the producing formation thickness and fracture skin are considered. Field examples will include both hard rock and soft rock fracturing case studies.
The importance of this analysis is paramount for operators trying to optimize high value hydraulic fracture treatments.
Estimating Fracture Reorientation Due to Fluid Injection/Production
Authors: Zhai Zongyu , Sharma Mukul M. 
Published: December 2007

Abstract
The injection or production of large volumes of fluid into or from a reservoir can result in significant changes to the effective in-situ stress distributions. Field evidence of this has been provided in the past by mapping refracturing treatments in tight gas sands and micro-seismic monitoring of injection wells in water-flooded reservoirs.
A poro-elastic model is presented to show how the extent of fracture reorientation can be estimated under different conditions of fluid injection and production. The extent of fracture reorientation is a function of the in-situ stresses, the mechanical properties of the rock and the pore pressure gradients. In reservoirs where the pore pressure gradients are complicated due to multiple injection and production wells, fracture reorientation is sensitive to the net pore-pressure gradients. Fractures tend to reorient themselves towards the injection wells and away from production wells, if the pressure gradients are comparable to the in-situ stress contrast.
While far-field principal stress orientations are impacted only by in-situ stresses and pore-pressure gradients, near-wellbore in-situ stress orientation is also impacted by the hoop stress and the wellbore pressure. These can have a significant effect on near-wellbore fracture reorientation. The results of our model are compared with field observations obtained from micro-seismic monitoring of water injection wells. The implications of the results to refracturing operations and candidate well selection are discussed.
Formation Damage History in the Mature Fields of Campos Basin Offshore Brazil
Authors: Rodrigues V. F. , Neumann L. F. , Miura K. , Tinoco F. L. , Netto J. B. M. L. , Daher J. S. 
Published: December 2007

Abstract
The Campos Basin mature fields, offshore Brazil, including the Marlim Field, are usually referred to as the World's deepwater field laboratory. The development of these fields was driven by the Brazilian state energy needs throughout the seventies and eighties, which induced a strategy of accelerating the projects implementation and anticipating their first oil. This sense of urgency is still dominant in Brazilian oil politics and has recently enabled the country to reach its oil self-sufficiency. That scenario throughout the last two decades encouraged risk assumption as well as the implementation of a considerable number of new technologies. Fifteen years after the first oil production from Marlim it seems that more engineered solutions are replacing the daring initiatives and the concise studies carried out in the beginning. Those years also testified an outstanding evolution of the drilling and completion technologies. The development advance to deeper and deeper waters brought up unpredicted problems such as wax deposition and hydrate formation. Thus, the history of the mature deepwater fields of Campos Basin offers great opportunities for learning, in a wide perspective. This paper summarizes the history of the damage and main completion troubles associated to Campos Basin deepwater mature fields. The aspects of prediction, prevention and remediation of the formation damage associated to drilling, sand control, stimulation, fines migration, organic deposition, scale, souring and other minor issues are addressed. The paper also presents some statistical data, predicted and unpredicted problems, and the ways they have and are currently handled. The technologies evolution and the most recent challenges are also shown. It is our belief that other deepwater mature fields to be developed and the new systems to be designed will certainly benefit from the experiences and lessons learned in the deepwater mature fields of Campos Basin.
Using Water Maps for E&P Environmental Protection and Remediation
Authors: Kofoed Val O. , Rollins Paul 
Published: December 2007

Abstract
This paper introduces a water-mapping technique that is particularly well suited to certain environmental protection and remediation tasks associated with petroleum production. In this procedure, electrodes are used to charge water systems with a low voltage electrical current. As the current flows through the water between the electrodes, it emits a magnetic field whose shape, depth and direction are characteristic of the surrounding aqueous network (Biot-Savart Law). This field is then read at the surface by a specially tuned receiver. The data thus generated can be used to create maps indicating the attributes of various subsurface water systems, including flooded oil fields.
The proven benefits of this mapping procedure are especially apparent in relation to water flooding and steam stimulation. As oil recovery techniques, these practices have significant benefits for the environment. By making existing oil fields more productive, they reduce the need for the development of new fields, thus avoiding the attendant ecological disruptions. In both maximizing their efficiency and minimizing their environmental impact, water-flooding practices are aided by water-mapping technologies.
When water and steam are forced through the chambers of an oil field, they sometimes emerge in unexpected places— carrying heavy crude. Such unanticipated surface expressions pose serious risks of environmental damage and lost production. By charting the potential flow paths of these floods, and identifying possible surface expressions, water maps help reduce the ecological impact and improve the productivity of flooding practices.
Furthermore, when groundwater has been contaminated, water maps play a critical role in remediation efforts. The greatest challenge in addressing groundwater contamination is gaining an accurate understanding of the complex web of channels and reservoirs which lie hidden below the surface. Remediation teams cannot deal with polluted water flows until they know where they are flowing. Here too, advanced groundwater maps offer critical information to those charged with protecting the environment. After detailing the theoretical science behind this technique, the paper will analyze the environmental implications of a recent deployment in the E&P industry.
A Mimetic Finite-Volume-Discretization Operator for Reservoir Simulation
Authors: Alpak Faruk O. 
Published: December 2007

Abstract
Accurate representation of complex reservoir geology using non-orthogonal meshes, upscaling of high-resolution geostatistical reservoir models including cross-flow effects, and strongly heterogeneous anisotropic permeable media such as cross-bedded sands and thin-bedded turbidite channels all individually or in combination give rise to simulation models with full-tensor permeability fields. Such anisotropic multiphase flow problems can be solved accurately on arbitrary non-orthogonal structured and unstructured meshes using the mimetic finite volume method. The discretization operator of the mimetic finite volume method satisfies conservation laws, and theorems of vector and tensor calculus on non-orthogonal, non-smooth, structured and unstructured computational meshes.
In this paper, we demonstrate the formulation of a three-dimensional variant of the mimetic finite volume method for corner-point geometry hexahedral meshes. We also discuss the results and issues associated with the implementation of the mimetic finite volume discretization operator in a parallel, fully-implicit research reservoir simulator developed using a general compositional formulation. Simulation results are presented for a variety of cases involving flow through geologically complex systems.
Foam-Assisted Lift—Importance of Selection and Application
Authors: Price B. P. , Gothard B. 
Published: December 2007

Abstract
The use of foamers to remove water from wells that are challenged by hydrostatic head pressure is common practice. The success of the process, however, is predicated on the proper selection of candidate wells, the proper selection of foaming agent, and application.
Foam assisted lift does not work on all wells. At a time when resources are in short supply, dividends are returned by applying resources to candidate wells that have been thoroughly screened to improve the success rate related to foam assisted lift technology. Properly formulated foaming agents will offer better value and return on investment than marginally performing products. Comprehensive evaluation of the application is critical to achieving the desired results of a foam assisted lift program.
Experience has demonstrated the importance of selection and application to the success of foaming agents. Foam assisted lift for economical production of adolescent and mature wells adds tremendous value and is a viable alternative for challenges related to liquid loading. Continuous improvement based on well changes must be considered as a significant part of the process.
Adopting a comprehensive process related to a deliquification strategy will allow for extended success of foam assisted lift programs, improved production rates and revenue, and improved resource utilization related to a better return on capital and resources expended.
Advances in Inhibitive Water-Based Drilling Fluids–Can they Replace Oil-Based Muds?
Authors: Patel Arvind , Stamatakis Emanuel , Young Steve , Friedheim Jim 
Published: December 2007

Abstract
This paper discusses the systematic design and development of high performance water-based muds and provides insight into the unique chemistry and inhibition characteristics of various amine inhibitors. Equally important, performance correlations of inhibitive systems in laboratory testing as compared to state-of–the-art inhibitive systems are included.
Invert emulsion drilling fluids have long been effective in drilling reactive shale. Developing high performance (highly inhibitive) water-based drilling fluid that would perform like invert emulsion drilling fluid has long been cited as the ultimate technical goal of the drilling industry. Progressive development of inhibitive water-based drilling fluids based on amine chemistry has made some impact on reaching this goal. Amine-based inhibitive drilling fluids have steadily gained popularity with service and oil companies.
However, these fluids have not always been completely successful in inhibiting the hydration of highly water-sensitive clays. The short-comings are particularly evident when drilling highly complicated and reactive shale formations. Keeping this in mind, an innovative highly inhibitive water-based drilling fluid has been systematically designed with the performance characteristics of oil-based muds.
The newly developed high performance water-based mud (HPWBM) comprises a unique polymeric amine shale intercalator for shale inhibition, an amphoteric polymeric shale encapsulator, a high performance lubricant/anti-accretion agent and a specialized fluid-loss additive. The newly developed HPWBM performed like an oil-based mud in laboratory testing as well as in offset wells using invert emulsion drilling fluids (OBM) due to highly complicated and reactive shale formations.
Parallel Automatically Differentiable Data-Types for Next-Generation Simulator Development
Authors: Younis Rami , Aziz Khalid 
Published: December 2007

Abstract
We develop and analyze an algorithmic framework and library of parallel automatically differentiable data-types written in the C++ programming language. In addition to representing variables and discretized expressions on a simulation grid, the data-types hide algorithms employed behind the scenes capable of automatically computing the sparse analytical Jacobian. Using the library, reservoir simulators can be developed rapidly by simply writing the residual equations, and without any hand differentiation, loops, or any other low-level constructs. The key challenge addressed is a technical development to enable this to run fast. Faster than if any of several existing automatic differentiation packages were used, faster than any purely Object Oriented implementation, and at least as fast as if a development team implemented hand-optimized residuals, analytical derivatives, and Jacobian assembly routines.
This is achieved by extending a generic programming technique specific to the C++ programming language known as Expression Templates. The extension enables its application to handle nested abstract types including sparse vector composites. Consequently, the library implementation can handle the complexity of any reservoir simulation model with optimal use of microprocessor hardware.
We demonstrate the ease of use of the library by presenting an efficient and rapidly developed fully-implicit simulator. Performance analysis is performed with varying grid size and is bench-marked with structured implementations. The tests are run with widely used compilers on standard microprocessors.

Introduction
Next generation simulators aim to simultaneously (1) leverage current technology to solve today's problems most efficiently, and (2) be easily extendable to leverage tomorrow's technology to solve tomorrow's problems most efficiently. Towards this, the General Purpose paradigm makes conceptual abstraction of equations and unknowns to achieve extendability to a wide range of formulations and recovery processes 1,2,3,4. Another kind of conceptual abstraction is on numerical formulations and solution processes, and aims to address extendability to evolving computer technologies and solution algorithms.
Motivation. Next generation simulator designs translate both conceptual abstractions into appropriate software-engineering abstractions. In this fashion, typical designs are made up of modules in a multi-layered framework 5,6,7,8. Each layer consists of modules with well defined interfaces that implement a certain level of functionality. Higher-layer modules implement increasingly complex functionality by using lower-layer modules. Apparent advantages of taller hierarchies are greater flexibility, extendability, and reliability.