bluuebunny/crossref_metadata_2025_split huggingface dataset:
Propellant Gas Fracture Stimulation of a Horizontal Austin Chalk Wellbore
Authors: Hollabaugh G. S. , Dees J. M. 
Published: December 2007

ABSTRACT
Oryx Energy has been drilling horizontal wells in the Pearsall Field of South Texas since 1985 and stimulating a number of these wells since 1989. Until 1992, stimulation techniques included acid washes, acid fracs and high rate water fracs. In 1992, Oryx Energy stimulated wells with high injection rate water fracs with varied success and high costs. A new stimulation method for these horizontal wells was desired to improve the degree of stimulation and reduce costs.
In 1992, a horizontal well was stimulated with a propellant gas fracture tool in an attempt stimulate the well in a method that would be cost competitive and have better results than the water fracs. The process permits simultaneous initiation of numerous multi-oriented fractures. The gas fracture propellant tool was designed to create fractures into the formation down the axis of the wellbore that are more or less perpendicular to the existing natural fractures. This treatment, while not economically successful, did result in sustained increases of oil, water and gas. This showed that the stimulation was successful in connecting some lesser depleted fracture intervals with ones that were producing before the treatment.
This paper reviews the results of Oryx Energy’s propellant gas fracture stimulation treatment of a horizontal well with 1028’ of 4 1/2" O.D. propellant in a 5 1/2" carrier run in an openhole wellbore. The job design, problems encountered, and results are reviewed in this paper.
Evaluation of the Performance of a New Upflow Design
Authors: Aretz H. J. , Stell J. D. 
Published: December 2007

Abstract
The design and performance of a new patented upflow vane developed by Burgess-Manning, Inc. is discussed in this paper. The BM 627 vane operates similarly to high performing Burgess-Manning horizontal flow vanes. The concept of shielding the separated liquid from the gas stream, used extensively for horizontal vanes, has been integrated into an upflow configuration.
In this paper a comparison of the performance of the new BM 627 vane to more traditional separation methods such as meshpads is presented. The test data will show that the new vane design outperforms other upflow configurations in separation efficiency, turndown ranges, and pressure drop.
The BM 627 vane incorporates the combination of hollow vanes which are interconnected with a drain channel. This design allows the separated liquid to be shielded and removed from the gas stream. The advantages of this new vane design include; higher velocities through the vanes, lower pressure drops across the vane bundles, higher separation efficiencies over an extended turndown range, and smaller vessel sizes. The BM 627 is also well suited for easy retrofits into existing vessels with meshpads. The supporting structure for the current meshpad can be utilized for the new upflow vane bundle, thereby eliminating the need for welding.
Analysis of Residual Corrosion Inhibitors in Oilfield Brines
Authors: Fortenberry C. L. , Grahmann N. J. , Miller C. D. , Son A. J. 
Published: December 2007

ABSTRACT
Ultraviolet (UV) spectroscopy can be used to detect low levels of organic corrosion inhibitors in produced water. An analytical method has been developed using a diode array UV spectrophotometer. The specifics of sample handling and preparation, and methods to stabilize samples for later analysis have been developed. The method is routinely used in the field as part of a comprehensive corrosion monitoring program. The partitioning behavior of corrosion inhibitors, between oil and water, can also be observed using this technique.
Steamflood Pilot Test in Waterflooded, 2,500-ft Tar Zone Reservoir, Fault Block II Unit, Wilmington Field, California
Authors: Lim F. H. , Saner W. B. , Stilwell W. H. , Patton J. T. 
Published: December 2007

ABSTRACT
A case history is presented of a tertiary, steamflood pilot project conducted from 1982–1989 in the Tar Zone reservoir of the Fault Block II Unit located in Wilmington Field, Los Angeles County, California. The design, implementation, performance and operations of the pilot are reviewed. Prior production mechanisms consisted of pressure depletion by solution gas drive followed by pressure maintenance using waterflooding. The 20 acre pilot area contained four, inverted 5 acre five-spot patterns. The reservoir steamflooded was the "D1" member, an unconsolidated sandstone, with 60 feet average thickness at a depth of about 2,550 feet. The nine production wells were completed open-hole with gravel-packed, wire-wrapped screens and were initially steam stimulated. The four injection wells were also completed open-hole with wire-wrapped screens. Using individual natural gas-fired, steam generators, high quality steam was continuously injected down insulated tubing into each injector.
During its seven year history, the steamflood pilot recovered 1.1 million barrels of oil from the injection of 7.2 million barrels ewe (cold water equivalent) of steam. The pilot project demonstrated successful field operations and an oil recovery factor of 75% (of the oil-in-place at the start of project) in this waterflooded, medium depth reservoir.
The pilot has been expanded to over 150 acres totalling 54 new production wells and 39 new steam injection wells treating both "T" and "D1" members of the Tar Zone in Fault Block II Unit.
An Improved Recovery and Subsidence Mitigation Plan for the Lost Hills Field, California
Authors: Wallace N. J. , Pugh E. D. 
Published: December 2007

Abstract
Maximizing oil recovery in the Lost Hills Diatomite Reservoir presents interesting technical challenges due to this reservoir’s low matrix permeability (less than 2 md) and thick net pay interval (600 to 800 feet). The high porosity (averaging 50%) and high oil saturation (up to 60%) provides significant incentive to improve and/or accelerate recovery considering the tremendous asset base of more than 2 billion barrels of oil-in-place.
Massive hydraulic fracturing, that placed as much as 3000 lbs/ft of sand, has been employed since the mid-1980s to accelerate recovery. Although these treatments have proven profitable, the accelerated fluid withdrawal and associated pressure depletion has increased compaction of the highly compressive diatomite. The compacting reservoir is causing a redistribution of stresses in rocks from the base of the productive interval to the surface. As a result, surface subsidence is occurring in the area of greatest development at a current rate of approximately 1 ft/year and wellbore integrity is at risk for a large number of wells. A waterflood project was initiated in January, 1991 to improve recovery and mitigate subsidence.
A Multidisciplinary Study Aimed at Optimizing Reservoir Management in a Gas Field With Over 30 Years of Production History
Authors: Erba Mario , Maioli Filippo , Dadda Giuseppe , Bolze Jean 
Published: December 2007

Abstract
This paper presents the methodological approach, the technical innovations and the results of an integrated reservoir study aimed at optimizing both final gas recovery and investments.
The main technical difficulties and economic constraints were due to the field limited reserves, the geological complexity of a torbiditic reservoir, the well recompletions dating back to 1959 and the daily rate at the limit of profitability.
Two phases were envisaged.
The results of the Phase 1, based on three key–well workovers, were the following: –a preliminary estimation of the remaining reserves;–the validation of a methodology for data collection;–the verification of the technical feasibility of the best well recompletion methodology.
The second phase, started only after a technical and economical evaluation of the results of the first one, was constituted of a complete reservoir study. This study is characterized by a multidisciplinary approach where all static and dynamic data were used and integrated. It was performed by applying innovative investigation methodologies, such as a detailed geomorphological–structural study and a cluster analysis based on cased hole logs.
The main results of the project were the reduction of economic risks and the optimization of final gas recovery by planning future actions of reservoir management and, particularly, the final development phase.
The Combined Effect of Capillary and Viscous Forces on Waterflood Displacement Efficiency in Finely Laminated Porous Media
Authors: McDougall S. R. , Sorbie K. S. 
Published: December 2007

ABSTRACT
Recent work on fluid flow upscaling in clastic facies has demonstrated the importance of both the small scale lamination structure and the local viscous/capillary force balance. This paper presents a pore-scale analysis of unsteady-state imbibition and drainage processes, which attempts to elucidate the interaction between capillary and viscous forces during waterfloods in such finely laminated porous media. Network simulation studies have been performed to evaluate their combined effect upon "residual" oil trapping and microscopic displacement efficiency.
The three main purposes of this paper are (i) to demonstrate these small scale structure/force balance mechanisms from first principles (i.e. from microscopic modelling at the pore scale); (ii) to examine sensitivities of the laminar capillary trapping mechanisms to various factors; (iii) to comment on aspects of the pore to core upscaling of these effects in the light of the recently proposed "geopseudo" methodology. Results demonstrate how small-scale lamination can greatly affect the larger-scale dynamics of a flood, especially where the principal flow direction is across the lamina as in cross-bedded systems. Sensitivity studies have been undertaken to examine the effects of lamina orientation and matrix wettability: a range of lamina structures has been considered under both water-wet and oil-wet conditions. The importance of scaling these effects in the light of the underlying geological structure is discussed. In the course of developing the network simulator for this study, some developments are presented on the modelling of the imbibition process.
Three-Phase Flow in Water-Wet Porous Media: Determination of Gas/Oil Relative Permeabilities Under Various Spreading Conditions
Authors: Kalaydjian F. J -M. , Moulu J. -C. , Vizika Olga , Munkerud P. K. 
Published: December 2007

Abstract
This paper aims at studying the impact of the spreading power (which rules the ability of the oil phase to spread on water in presence of gas) on three-phase gas/oil relative permeabilities and residual oil saturation. Relative permeabilities have been determined by the steady-state method for both increasing and decreasing gas saturation as well as by analyzing unsteady-state displacements.
These experimental relative permeabilities are finally compared together and to theoretical curves derived from an analytical model.
The differences observed between the relative permeabilities, and the effect of the spreading power on them as well as on the residual oil saturation are explained by pore scale mechanisms.
Case History: Cuttings Reinjection on the Murdoch Development Project in the Southern Sector of the North Sea
Authors: Schuh P. R. , Secoy B. W. , Sorrie Eric 
Published: December 2007

ABSTRACT
This paper describes how Conoco planned and implemented downhole injection of oil contaminated drill cuttings on the Murdoch development project in sector44/22 of the Southern North Sea. Five wells were predrilled through a template from December 1991 to March 1993.The firstwell, 44/22 D-1, was drilled as a producer and was also designed and used as the injection well for all subsequent wells. Injection was conducted via the 13-⅜" × 9-⅝" annulus. The casings were designed to accomodate the injection loads. The injection interval was the Triassic Bunter, a sand/shale sequence between 6200'-7000'TVD, bounded by 200' of salt above and 1500' of shale below. Topside equipment consisted of a prototype Cuttings Processing Package (CPP), a screw conveyor, a slurry storage tank and a small triplex pump.
The Argyll Field Life Cycle with Cost Control as the Operator's Ethos
Authors: Methven J. O. 
Published: December 2007

ABSTRACT
The Argyll field came onstream in June 1975 and produced the first oil from the United Kingdom Continental Shelf (UKCS). The floating production concept adopted for the field demonstrated an innovative cost efficient approach to developing a marginal field. The initial field life expectancy was three to five years and cost sensitivity was embraced as the only viable way to ensure that the field survived longer than originally forecast.
This paper reviews some of the Argyll field innovations from initial design into ongoing operations and on through to abandonment. Technical solutions which result in low capital investment but then give higher than preferred operational costs, do not necessarily result in reduced field life. A Tight" approach to operational cost control is vital in the early years of a field's life so that later year cost control is a natural progression and not a desperate rearguard action.
Cost control is a state of mind and must be engendered into the Ethos of a company. The question, why?, is probably the most powerful tool that any individual can apply in the approval process, no matter the level of that approval. Expenditure approval set at an appropriate level coupled with staff committed to a continuous search for improvement, results in an operations group which manages their own business. This level of understanding acts on market changes rather than reacting to change, thus resulting in true cost control.
Pipeline Freespan Evaluation: A New Methodology
Authors: Kaye David , Galbraith David , Ingram James , Davies Russell 
Published: December 2007

ABSTRACT
A methodology for the rigorous assessment of pipeline freespans is described, together with a description of its application to the Beryl Field network of pipelines.
The methodology is in two parts, each with two stages, and comprise preliminary stress and vibration frequency checks followed by detailed strain and fatigue life checks where appropriate. Comprehensive software, automatically linked to the inspection database, has been written to allow efficient use of the methodology.
The use of a new ROV based freespan rectification technique is also described.
Both the assessment and rectification techniques were successfully used in Mobil's Beryl field and the SAGE pipeline in 1992.
Simultaneous Inversion of Galvanic and Induction Logging Measurements to Improve Resolution
Authors: Mezzatesta A. G. , Payton C. C. , Strack K. M. , Tabarovsky L. A. 
Published: December 2007

Abstract
Improved resolution in estimating formation resistivities can provide more accurate values of residual and movable hydrocarbon saturations. Routinely, formation resistivity information derived from galvanic and induction logging measurements are interpreted independently. As a result, several models of formation resistivity can emerge that are typically not consistent. Here, we illustrate how simultaneous inversion of data from galvanic and induction tools can yield more consistent and better resolved parameters.
When measuring formation resistivities, different References and illustrations at end of paper physical principles govern galvanic and induction tools. In galvanic tools, the voltage differences measured are related to the surface charges at the interfaces between adjacent media of different resistivities, whereas in induction tools, the voltage induced in a measuring coil is caused by magnetic fields of alternating currents flowing in the surrounding formation.
A joint inversion of galvanic and induction data is proposed, in which a single earth model, consisting of a distribution of resistivities, is simultaneously applied to the two types of measurements. Combining measurements based on different physical principles also improves resolution. A complete concept of resolution is proposed that involves earth model, measuring device, data noise, and interpretation technique as components.
A number of earth models and tool combinations (Dual Laterolog, Dual Induction, Thin Bed Resistivity Tool, Microlaterolog) are analyzed and discussed under the framework of the proposed resolution concept. The analysis clearly shows the advantages of combining data from different instruments to improve interpreted results.
Use of Tubular Sucker Rod Pumping to Produce High Viscosity Oil: The Problem and Some Solutions
Authors: De Araújo F. R. 
Published: December 2007

ABSTRACT
The objective of this work is to show the experience in the use of tubular plunger pumps for production in viscous oil, in the Estreko and Alto do Rodrigues fields.
Based on the fields surveys we observe "in loco" the problems existents and analyse them. Suggestions were made for pumps changes, with the purpose of improving its performance.
Cargo loss calculations in the traveling valve annular were made using the "BULLETIN API 13D".
A Survey of Field Applications of Gel Treatments for Water Shutoff
Authors: Seright R. S. , Liang J. 
Published: December 2007

ABSTRACTPreviously published field results were examined to determine if they reveal usable guidelines for the selection of wells as candidates for gel treatments. Views of seven gel vendors and experts from eight major oil companies were also examined concerning the selection and implementation of gel treatments in injection and production wells.This study demonstrates that gel treatments have been applied over a remarkably wide range of conditions. Unfortunately, the success rates for these projects have been very sporadic. Our analysis indicates that the producing water/oil ratio was usually the only criterion used to select candidate wells.To improve the success rate for future gel applications, the source and nature of the water production problem must be adequately identified. Results from interwell tracer studies and simple injectivity and productivity calculations can be especially useful in this diagnosis. Recovery calculations should indicate that considerable mobile oil remains that could be recovered more cost-effectively if a blocking agent could be realistically placed in the proper location.Improvements are needed in the methods used for sizing gel treatments. The method of sizing should be tailored to the type of channeling problem encountered. Five different types of channeling problems are discussed.
Petrographic Characteristics of Productive and Non-Productive Sandstones, Canadon Minerales Field, San Jorge Basin, Argentina
Authors: Davies D. K. , Dienger L. , Selva C. , San Martin H. 
Published: December 2007

ABSTRACT
The accuracy of formation evaluation in sandstones of Caήadon Minerales Field has been significantly improved through knowledge of detailed rock composition, pore geometry and cation exchange capacity. Prior to the implementation of a program of integrated petrographie and wireline log analysis, 50% of perforated zones either did not flow or flowed water. As a result of the integration of rock and log derived data, more than 85% of perforated zones in this field flow hydrocarbons.
A Rheological Model for Polymer Foams
Authors: Winkler W. , Valkó P. P. , Economides M. J. 
Published: December 2007

Abstract
A new principle, that of Volume Equalization has been applied to characterize the flow behavior of Nitrogen-HPG-Gel foams. Large scale vertical and multi -diameter horizontal experiments were conducted at two different temperatures within both the laminar and the turbulent flow regimes. Pressure loss calculation procedures independent of pipe size and inclination were investigated. Instead of the previous available turbulent pressure drop correlations a fluid mechanics description of drag reduced foam flow was applied making use of a new form of Reynolds number.
A Waterflood Model Based Upon Percolation Theory Concepts
Authors: Barrufet M. A. , White R. J. 
Published: December 2007

ABSTRACT
This paper presents a novel application of percolation theory for the development of a three-dimensional two-phase waterflood model.
The waterflood model consists of a three-dimensional, two-phase cubic reservoir composed of many smaller cells. The model represents one-quarter of a five spot waterflood pattern and has one injection well at one corner and a production well at the opposite corner.
Two different random numbers are allocated to each cell throughout the lattice. Based upon the first random number, one decides upon the contents of the cell (oil or water). The permeability of that cell is determined from the second random number, which belongs to a log-normal distribution density. The lattice is swept cell by cell with the displacing fluid (water) following certain invasion rules. The model stores the oil and water clusters (aggregates) as well as the fluid production. The simulated waterflood process terminates when no more oil is produced. Then the residual oil saturation (trapped oil) is computed and the spatial location in the lattice is printed (graphed). These simulations were done on a CRAY Y-MP2/116 Supercomputer using vectorized code.
Several characteristics of this model were investigated: First, the effect upon the residual oil saturation of different initial water saturations; second, the effects of fluid allocation by using different probability distribution functions, i.e. uniform, normal, and Beta distribution densities; third, the effect of different parameters in the log-normal distribution for permeabilities to indicate different degrees of heterogeneity of the porous media; and last, the effect of lattice size upon the residual oil saturation. The results are encouraging, and we envision that the model could be extended to layered reservoirs.
Simulation of Water Coning Behavior Using Geostatistic Techniques to Represent Reservoir Heterogeneities
Authors: Beraldo V. T. , Pedrosa O. A. , Remacre A. Z. 
Published: December 2007

ABSTRACT
Numerical simulation has been applied to study the water coning behavior in a well producing from a highly heterogeneous reservoir in an oil field located in the onshore part of the Potiguar Basin, Rio Grande do Norte, Brazil. In this reservoir, the scale of lateral heterogeneities is too small to be represented by layer average properties.
Small scale heterogeneities in the drainage area of the well were modeled by sequential stochastic simulation of categorical variables representing flow units of the reservoir. Variographic analysis was performed using logging and core data from the reservoir and also data from outcrops in the same depositional enviroment.
The purpose of this work was to evaluate the effect of small lateral heterogeneity on the water coning behavior. This was accomplished by history matching production data and numerical results of flow simulation performed in geostatistic realizations of the reservoir.
Geologic and Stochastic Characterization of Naturally Fractured Reservoirs
Authors: Guo G. , Evans R. D. 
Published: December 2007

ABSTRACT
New techniques for characterizing naturally fractured reservoirs are presented. Fundamental fracture units defined from geologic analyses are identified, and their corresponding permeability tensors analytically derived. The integration and synthesis of different fracture units provide realistic and mathematically tractable conceptual models for the analysis of naturally fractured reservoirs. A technique for modelling more complex fracture systems is also developed to stochastically simulate the fracture geometry based on the probability distributions of fracture characteristics. The permeability tensor distribution of the simulated fracture system is then calculated by a numerical method. The combination of these two techniques constitutes a comprehensive methodology for a realistic and quantitative characterization of naturally fractured reservoirs.