bluuebunny/crossref_metadata_2025_split huggingface dataset:
Prediction of Future Well Performance, Including Reservoir Depletion Effects
Authors: Poe B. D. , Elbel J. L. , Spath J. B. , Wiggins M. L. 
Published: December 2007

ABSTRACT
In the past, the reservoir material balance (voidage) effects occurring between the end of the measured (known) production history and future Inflow Performance Relationship (IPR) time levels have been commonly ignored in the computation of the future IPR behavior. Neglecting the reservoir voidage that occurs during the time interval between the end of the known production history and the future IPR time levels results in erroneous estimates of the future IPR behavior.
A detailed description is given of the mathematically rigorous technique that has been used in the development of a multilayer well performance simulator that properly accounts for the reservoir voidage effects. Some of the more significant results are also presented of an extensive effort to develop an accurate and computationally efficient well performance simulation model.
The reservoir can be considered to be multilayered, with mixed reservoir layer completion types and outer boundary shapes, drainage areas and boundary conditions. The well performance model can be used to simulate performance in three different operating modes: (1) constant wellhead rate, (2) constant bottomhole pressure, and (3) constant wellhead pressure. The transient performance of vertical, vertically fractured and horizontal wells can be simulated with this well performance model. The well performance model uses mathematically rigorous transient solutions and not simply the approximate solutions for each of the well types, as do most of the other commercially available well performance models.
An Evaluation of a Method to Predict Unknown Water Levels in Reservoirs and Quantifying the Uncertainty
Authors: Haynes Byron 
Published: December 2007

Abstract
A technique developed by Hawkins, et.al.(l) which integrates log and core data to predict water levels in hydrocarbon reservoirs has been evaluated using Alaska, Gulf of Mexico and North Sea reservoirs. The method is based on the construction of a synthetic capillary pressure curve from porosity, permeability, and water saturation at each available data point in the rock column. Regression analysis is used to estimate the Free Water Level (FWL) and an associated confidence interval. Conversely, if the FWL is known, the model can be used to estimate porosity, permeability, or water saturation, when two of the three parameters are known.
Typically, water contacts are located by drilling down structure wells, by obtaining pressure information from RFT's or DST's, or by capillary pressure data. Unfortunately, estimating water contacts from RFT's, DST's and down structure wells requires the water contact be penetrated. Available capillary pressure measurements, although scarce, can be used to estimate the vertical distance to the FWL, defined as the point of zero capillary pressure for the hydrocarbon/water column.
This is performed by superimposing the estimation of the water saturation, at that depth, on the curve. The distance to the FWL (or water contact) from that point can be identified by converting the capillary pressure curve to height above the FWL. Although penetration of the water contact is not required with this method, it does assume homogeneity of the rock column.
However, the advantage of the capillary pressure model technique over the above technique is that it does not assume the rock interval is homogeneous but uses measured porosity, permeability, and water saturation data. Additional strengths of the capillary pressure model approach to determining water level are: reliable FWL estimation in a transition zone, prediction of rock properties and water saturations, and a consistency check of capillary pressure data. No analysis of data consistency was performed in this work. However, it is apparent that since the model is a functional form of capillary pressure behavior, estimates of displacement pressures can be checked along with the shape of the data in the high pressure region.
Viscosity Correlations for Gulf of Mexico Crude Oils
Authors: Petrosky G. E. , Farshad F. F. 
Published: December 2007

Abstract
New empirical viscosity correlations for estimating dead oil, saturated oil and undersaturated oil viscosities have been developed as a function of commonly available field data.
Results show that these viscosities can be predicted with average absolute errors ranging from 2.91% for undersaturated oil viscosity to 14.47% for saturated oil viscosity.
Economic Potential and Optimum Steamflood Strategies for Trough Reservoirs of San Joaquin Valley, California
Authors: Hong K. C. , Use D. J. 
Published: December 2007

Abstract
Many trough reservoirs in the Western San Joaquin Valley, California, remain undeveloped because reserve bases are relatively small and occur in areas where thermal recovery activities have been low. Reservoir models with different configurations and reserve bases were used to compare the economic potential of these reservoirs and to develop guidelines for selecting reservoirs that can be economically exploited. The models were also used for determining the optimum steamflood strategies for the selected reservoirs.
The study showed that, for a trough reservoir to be an economical prospect, it should contain a minimum oil-in-place of 300 MSTB per pattern length along the trough between the synclinal axis and the gas-oil contact. Optimum steamflood strategy for such reservoirs includes: (1) placing the injector away from the synclinal axis and gas-oil contact, (2) having a row of producers updip from the injector and another near the synclinal axis, (3) starting the steamflood with an intermediate rate and high quality of steam, and (4) shutting-in steam injection after 5.5 years of continuous injection at a constant rate. This strategy can result in a annual rate of return of 20%.
Monitoring Circulatable Hole with Real-Time Correction: Case Histories
Authors: Griffith James E. , Ravi Kris M. 
Published: December 2007

Abstract
This paper presents case histories that demonstrate the utility and economy of monitoring circulatable hole (CH) immediately before a primary cement job, and then taking real-time action to correct any deficiencies detected. Although it is well established that effective hole-cleaning is critical to the success of a cementing job, a reliable method has only recently been made available for continuously monitoring the volume of the casing-to-wellbore annulus. Accurately determining the annular volume involved in the circulation process is the key to verifying that the hole is clean. Traditionally, operators have circulated the annulus for an arbitrary length of time; CH monitoring, however, has allowed for accurate assessment of hole condition with as much as 75% less circulation time before cementing.
The case histories presented describe methods used to correct CH deficiencies once they are established. These methods include
Pumping at higher rates Rotating and/or reciprocating pipe Adding spacers/flushes to the mud system
Based on the case histories presented, the following benefits can be derived from the new measurement method:
Circulation times originally averaging 2 hours may be reduced to as little as 30 minutes. Pipe movement can contribute greatly to the amount of CH. Operators can save the expense of certain casing equipment traditionally used to increase CH since they know 100% of the annulus is in circulation.
Expansion-Contraction Cycles for Cement Optimized as a Function of Additives
Authors: Talabani Soran , Hareland Geir 
Published: December 2007

Abstract
An experimental study was carried out to investigate the addition of specific additives to cement in order to eliminate the micro-fractures and micro-annuli that cause gas migration.
The experiments performed monitored the change in the cement slurry pressure during the setting of the cement. During the setting period of the cement, two time cycles of cement expansion and contraction were observed. This is due to the individual contributions of each part of the cement mixture. To obtain the optimum tightness of the cement, final optimum concentrations of the additives were obtained experimentally, where the cyclic pressure behavior of the cement was optimized for the best final cement results.
By utilizing the correct amount of Anchorage Clay, XC-Polymer, Ironite Scavenger, Ultrafine cement and Synthetic Rubber powder in a class G mixture at a given temperature and confining pressure, an impermeable cement mixture can be obtained. The correct amount of Synthetic Rubber used for cyclic pressure reduction is a function of cement setting temperature and pressure as well as the elastic properties of the rubber.
By using laboratory testing at different pressure and temperature with different rubber concentrations and elastic properties, it is estimated that the entire annulus can have an impermeable cement from surface to total depth. The difference in temperature and pressure with depth dictates the concentration and elastic properties of the rubber as the required expansion and contraction changes with depth.
Field Experience With Application of Blast Furnace Slag to the Drilling and Cementing Program in the Stratton Field, South Texas
Authors: Daulton D. J. , Bosworth S. J. , Pumphrey Bill , McCathy Scott , Cantu Rene , Clendennen John 
Published: December 2007

Abstract
In an attempt to provide better annular zonal isolation between productive (gas producing) and nonproductive (water bearing) intervals an unorthodox program was proposed and implemented based upon the incorporation of Quick Quenched Blast Furnace Slag (QQBFS) to both the drilling mud (universal fluid) and cement slurries. To date this is the deepest 7500 to 7900 ft (2345 to 2407 m) and hottest (225 F / 107 C bottom hole static temperature) dual application of QQBFS in the industry. A four phase program of progressive steps were taken with respect to field application during this project to implement cost saving measures without sacrificing quality services. During this project, fourteen dual 2 7/8" (7.30 cm) 6.5 lb/ft (9.67 kg/m) N-80, EUE production strings were successfully completed within 9.875/8.75 inch (25.08/22.225 cm) hole. A dramatic reduction in remedial squeeze operations has been reported with no squeeze jobs being performed on the last seven (7) wells completed. This type of success will benefit not only operators but state and federal regulatory bodies who are seeking to determine the "field worthiness" of QQBFS as a hydraulic material alternative for the oil and gas industry.
Water Shutoff Through Fullbore Placement of Polymer Gel in Faulted and in Hydraulically Fractured Producers of the Prudhoe Bay Field
Authors: Lane R. H. , Sanders G. S. 
Published: December 2007

Abstract
Selective shutoff of undesired water influx by nonselective (fullbore) placement of treating chemicals has been successfully demonstrated in production wells of the Prudhoe Bay field. This was accomplished through: (1) careful choice of candidates with known high conductivity water influx pathways (fault, hydraulic fracture, thief), (2) placement that exploited conductivity differences without zonal isolation, and (3) use of established polymer gel chemistry with previously demonstrated ability to shut off water preferentially to oil.
Large Scale Oil Lease Automation and Electronic Custody Transfer
Authors: Price C. R. , Elmer D. C. 
Published: December 2007

ABSTRACT
Typically, oil field production operations have only been automated at fields with long term production profiles and enhanced recovery. The automation generally consists of monitoring and control at the wellhead and centralized facilities1,2. However, Union Pacific Resources Co. (UPRC) has successfully implemented a large scale automation program for rapid-decline primary recovery Austin Chalk wells where purchasers buy and transport oil from each individual wellsite. This project has resulted in two significant benefits. First, operators are using the system to re-engineer their work processes. Second, an inter-company team created a new electronic custody transfer method. This paper will describe:
The progression of the company's automation objectives in the area. The field operator's interaction with the system, and the related benefits. The research and development of the new electronic custody transfer method.
Downhole Emulsion Breaker Injection into the Lift Gas Stream
Authors: Lagerlef David L. , Sindelar Scott T. , Lelland William G. Me , Blumer David J. 
Published: December 2007

ABSTRACT
A program is in operation at Prudhoe Bay, Alaska which injects emulsion breaker downhole with lift gas to enhance production. This paper addresses the reasons emulsions can limit production in a gas lifted well and the benefits that can be realized by breaking the emulsion downhole. A discussion of the simple but effective produced fluids emulsion screening test and the field implementation of downhole emulsion breaker in wells at Prudhoe Bay are included in this paper.
The emulsion breaker inhibits the formation of highly viscous emulsions by acting downhole. Along with increased production of nearly 3000 bopd for 22 wells, gas lift efficiency has been enhanced, heading of these wells has decreased, and less back pressure in the produced fluid gathering lines to the processing facility has been observed. The processing facilities have also experienced a reduction in the amount of emulsion breaker usage and a reduction in the volume of unbreakable emulsion pads going to produced water disposal.
Wells that are gas lifted, produce small fines, and generally are above 50% water cut may be susceptible to production of high viscosity emulsions. Downhole emulsion breaker injection can result in lower friction losses in the tubing string and other benefits in the entire production system. Downhole emulsion breaker injection can provide system wide benefits when tight emulsions are being produced.
Solid Particle Deposition During Turbulent Flow Production Operations
Authors: Escobedo Joel , Mansoori G. A. 
Published: December 2007

ABSTRACT
The production and transportation of petroleum fluids could be severely affected by deposition of suspended particles (i.e. asphaltene, paraffin/wax, sand, and/or diamondoid) in the production wells and/or transfer pipelines. In many instances the amount of precipitation is rather large causing complete plugging of these conduits. Therefore, it is important to understand the behavior of suspended particles during flow conditions.
In this paper we present an analysis of the diffusional effects on the rate of solid particle deposition during turbulent flow conditions (crude oil production generally falls within this regime). The turbulent boundary layer theory and the concepts of mass transfer have been utilized to calculate the particle deposition rates on the walls of the flowing conduit. The developed model accounts for the eddy and Brownian diffusivities as well as for inertial effects.
The analysis presented in this paper shows that rates of solid-particle deposition (during crude oil production) on the walls of the flowing channel due solely to diffusional effects are small.
It is also shown that deposition rates decrease with increasing particle size. However, when the process is momentum controlled (large particle sizes) higher deposition rates are expected.
Slack-off Load Transmission in Horizontal and Inclined Wells
Authors: Wu Jiang 
Published: December 2007

ABSTRACT
This paper studies the wall contact force, frictional drag, and slackoff load transmission for tubulars in inclined and horizontal wellbores. The wall contact force of helically buckled tubulars in horizontal and inclined wellbores shows to have the same expression as that in vertical wells. New wall contact force of sinusoidally buckled tubulars is modeled and expressed as half of that of helically buckled tubulars. Equations for the axial load distribution of buckled tubular and the transmitted tubular bottom load are also presented. It is shown that less load is transmitted to the tubular bottom, and helical buckling (or even "lockup") occurs much earlier, when the frictional drag from sinusoidal buckling is considered. The results can be used to improve the frictional drag and load transmission calculation for tubular operations (drillstring, tubing, and coiled tubing) in horizontal and inclined wells.
Statistical Analyses of Shape Factor and Productivity Index for Horizontal Wells
Authors: Faruqi S. A. , Malekzadeh D. , Day J. J. 
Published: December 2007

ABSTRACT
The performance of horizontal wells in bounded anisotropic reservoirs has been investigated using the statistical analysis. New statistical models for calculating the fraction of horizontal well length contributing to unrestricted production, and horizontal well shape factor, are presented.
The concept that the performance of horizontal well of halflength Xfl with mechanical skin can be replaced by the performance of an equivalent horizontal well of half-length Xf2 with no mechanical skin is used. The statistical analysis showed that for a given reservoir shape and well asymmetry, the horizontal well shape factor can be directly correlated with three dimensionless parameters, XLD, rw/h, and LD, which are functions of reservoir and well parameters. These statistical correlations can easily be used to predict the performance of a damaged and/or stimulated horizontal well without the need to use complex numerical and/or analytical solutions which require extensive computer use.
Fracturing Fluid Interactions With Formation Minerals and Their Subsequent Effect on Formation Permeability
Authors: Thompson J. E. , DeVine C. S. 
Published: December 2007

ABSTRACT
The selection process of hydraulic fracturing fluids for oil and gas well stimulation applications largely ignores interactions of the stimulation filtrate and the broken stimulation fluid with formation minerals. Fluid interactions with formation minerals may have a significant influence on formation permeability and subsequent well production. Laboratory formation core regain permeability studies, subsequent to the injection of both low and high pH fluids, were conducted to measure fluid effect on core permeability. Results of these tests indicate that both the rock mineralogy and the pore system morphology are affected by contact of the rock with filtrate from the injection of an unbroken stimulation system into the formation. Formation permeability after treatment with stimulation fluid can be significantly influenced by formation-injection fluid interactions. Studies have demonstrated that, depending on the specific formation mineralogy, post-injection permeability may be increased by low pH systems only, by high pH systems only, or by either low or high pH systems.
The focus of this paper is to identify specific formation minerals which may potentially be affected by contact with fracturing fluid filtrate and broken fracturing fluid and to relate increases in formation permeability to resultant fluid-rock interactions. Mechanisms of fluid-formation interactions and chemical reactions are presented.
Design Guidelines for Artificial Barrier Placement and Their Impact on Fracture Geometry
Authors: Barree Robert D. , Mukherjee Hemanta 
Published: December 2007

Abstract
Fracture height growth can be contained by selective placement of a low mobility bed of proppant along the upper and the lower tips of a propagating hydraulic fracture, while keeping the front tip open to further lateral extension. This is done in a separate treatment step prior to the main treatment. The success of these treatments in reducing height growth depends on the proper design and execution of the treatments, based on knowledge of the vertical stress profile, which dominates the fracture geometry evolution in three dimensional space. Such barrier placements are limited by the rate of early fracture height growth with respect to extension, treatment rate, fluid viscosity, proppant concentration, proppant size and specific gravity. This paper shows the effects of these variables on the effectiveness of the placement of artificial barriers. The paper also describes the three dimensional fracture geometry evolution beyond the lateral extent of the emplaced barriers. Beyond these barriers the fracture loses any artificial containment, and grows according to the natural stress profile. The possibility of interactive diversion through convective settlement is also studied.
Effective Hydraulic Fracture Length and the Determination of Productivity Index
Authors: Malekzadeh Dariush , Khan Farid U. , Day John J. 
Published: December 2007

ABSTRACT
This paper presents a new technique for analyzing the performance of hydraulically fractured vertical wells in bounded reservoirs. The main objective is to present a new set of practical equations, based on the recently introduced concepts in well testing, for evaluating the effective length of the hydraulic fracture contributing to unrestricted production. It is determined that the performance of a hydraulically fractured vertical well with mechanical skin and fracture half length Xf1 can be substituted by the performance of a fractured half-length Xf2 with no skin. New equations presented in this paper can be used to determine pseudo skin factor, effective fracture half-length, mechanical skin factor, shape factor, and productivity index of fractured vertical wells. The new equations and guidelines given in this paper can be used to determine the magnitude of formation damage around hydraulically fractured vertical wells and to evaluate the success of the stimulation treatment. An example based on simulated well test data is presented to illustrate the application of the new technique. The problems associated with the use of the finite-conductivity fracture model are discussed and it is recommended that the pressure transient data obtained on fractured vertical wells be analyzed with effective hydraulic fracture length concept, in preference to the finite-conductivity fracture model.
Research on Energy Balance Test of ESP
Authors: Zhen-hua Cui , Jun Zhu 
Published: December 2007

Abstract
Electrical Submersible Pump (ESP) is a kind of important means in the oilfield mechanical recovery. People used to place the emphasis on calculating the energy losses of every component by piece in the applications, and no test data were established.
This paper takes ESP as a system, and gives theoretical analysis on the energy losses of every ESP component. Energy balance test of ESP system is performed in test well for the first time, the pattern of energy-loss distribution is found and some proposals on improving the design, manufacture and application of ESP system are put forward. In addition, the test procedure and calculating method of energy losses for ESP system is offered.
Interference Test Analysis in Naturally Fractured Reservoirs
Authors: Ma Q. , Tiab D. 
Published: December 2007

Abstract
The directional flow properties of a reservoir are very important for the design of reservoir development and waterflooding. For a reservoir with natural fractures, the permeability is controlled by the preferred orientation of the fractures. This paper presents the results of an investigation for determining the fracture orientation from interference tests. The pressure response is analyzed based on the double porosity model proposed by Warren and Root. The calculations are performed numerically by use of Stephest Laplace inversion transform. The results show that the transition flow period depends not only on the fracture flow parameters, but also on the distance between the observation well and the active well. Based on this characteristic, a new method is presented to determine the fracture orientation and permeability components as well as the fracture-flowing parameters.