bluuebunny/crossref_metadata_2025_split huggingface dataset:
Pressure-Transient Response of an Infinite-Conductivity Vertical Fracture in a Reservoir with Double-Porosity Behavior
Authors: Houzé Oliver P. , Horne Roland N. , Ramey Henry J. 
Published: December 2007

Summary
This paper describes the behavior of a naturally fractured reservoir when a well is producing through a vertical fracture with uniform flux or infinite conductivity. The reservoir model is a double-porosity medium, and both pseudo-steady-state and transient-interporosity-flow models are studied. The derivative vs. time for each solution is shown, and an analysis method for matching field data to such a model is presented.
This study combines a reservoir and a well model, both of which have been extensively studied separately. Included are a quick review of the main characteristics of these models and the methods used to solve the problems. At the end of the study, a general method is suggested to extend models with constant boundary conditions—e.g., homogeneous and double-porosity cases.
Thermal Visbreaking of Heavy Oil During Steam Recovery Processes
Authors: Shu W. R. , Hartman K. J. 
Published: December 2007

Summary
This paper describes a simulation study on the effect of visbreaking on heavy oil recovery during steam injection processes. The kinetic rate constant for in-situ visbreaking was derived from in-house kinetic data and then used in conjunction with a thermal compositional simulator to assess the effect of visbreaking on recovery through a series of numerical experiments. Various steam injection strategies were tested and the effect of visbreaking studied. In some cases, physical heating, not thermal visbreaking, was the dominant recovery mechanism. In other cases, visbreaking had a large effect on recovery. The difference was primarily a result of the placement of the visbroken oil with respect to the direction of flow. In cases where the visbroken oil zone was perpendicular to the flow, it formed a mobility transition zone that improved sweep, thus enhancing oil recovery.
A Field Experiment of Improved Steamdrive With In-Situ Foaming
Authors: Brigham W. E. , Marcou J. A. , Sanyal S. K. , Malito O. P. , Castanier L. M. 
Published: December 2007

SummaryThis paper reports on the design and execution of a field experiment on recovery of heavy oils by steamdrive enhanced by additives. The goal of this project was to study the effect of injection of a commercial surfactant (Suntech IV™) and N2 on the behavior of a conventional steamdrive. Because the laboratory studies leading to the design and implementation of this field experiment have been referenced many times, we emphasize here the field data obtained in reservoir definition, monitoring of the experiment's progress, and production evaluation in a heavy-oil reservoir. Several standard and experimental analytical methods were applied, and their validity in the Kern River field test is discussed.Three slugs of surfactant and N2 were injected at different rates. Analysis of the results shows a considerable improvement in oil recovery by steamdrive caused by the addition of surfactant and N2 to the steam. The changes in production behavior of the reservoir caused by the additives are analyzed and discussed. Although the economics of this project is difficult to determine at this point, it looks promising.
Slim Hole Technology - An Economic Key to Future Drilling Developments
Authors: McLaughlin Philip L. 
Published: December 2007

Introduction
"Based on present allowables, probably more than half the wells in Texas today could be produced through 1.5-in. tubing", stated Philip L. McLaughlin, president of The McLaughlin Co., Dallas, at a recent meeting of the Mid-Continent Section Study Group in Tulsa, Okla. McLaughlin, who was very closely associated with slim hole drilling and completion techniques and equipment while employed by the Cardwell Manufacturing Co., spoke to the Mid-Continent Section Study Group on the economics of slim hole drilling and completions.
McLaughlin, owner of a firm which specializes in product market research and "assistance programs" for oil companies, opened his discussion by warning the group that since the oil industry is in a period of dynamic transition; oil companies, drilling contractors, service companies and equipment manufacturers must continually make themselves stronger as an industry and more alert to opportunity if they expect to continue their past progress.

Oil Industry Needs New Ideas for Economic Survival
"If oil is to economically survive in our lifetime, it must show a greater willingness to seek out, test, develop and adopt new ideas and new methods. Many research departments are thinking too small to create big deeds. There is a dire need of a freer exchange of information at all levels of each segment of our industry." Much of our present day equipment has outlived its economic usefulness-demanding an engineering revolution similar to the one the auto industry experienced in the late thirties.
To cope with this transition which is resulting from keener competition, poorer economic conditions, higher dry hole ratios and fewer reserves found for each well drilled, coupled with technical and management complacency, he advised that the oil industry must either develop methods of economizing, change "fixed idea" and "ivory tower thinking", or receive a much lower return on investments. "If 15 per cent depletion allowance is passed, I expect a great engineering and economy revolution that must come, will develop in a hurry or the oil industry is likely to wake up some day and find itself, joining the railroad industry, as the second biggest ‘sleeping giant’ in U. S. history.
A Summary of Unitization and the Engineering Functions in Unitization
Authors: Landis Bruce A. 
Published: December 2007

Introduction
A wealth of valuable, well documented information about unitization exists today. Consequently, the scope of this presentation will be confined to (1) a summary of the over-all picture of unitization and (2) a review of the specific function of the petroleum engineer in the formation of fieldwide producing units involving secondary recovery operations.
A fieldwide producing unit can be defined as a unit comprised of lands that are producing or are reasonably proved to be productive at the time the unit is formed. Such lands usually embrace all or substantially all of a reservoir (common source of supply) in an established field. Such units are usually formed for the purpose of initiating some type of secondary recovery operations, but they may be formed for more efficient operations such as selectively producing certain wells, etc. which will have the effect of increasing ultimate recovery.
Sometimes units of substantial size involving a number of wells, but which do not include all or most of a field, are classed as fieldwide producing units to distinguish them from so-called spacing units. In fieldwide producing units, usually the entire 8/8 interest is unitized; i.e., the oil company's interest and all of the royalty interest are unitized. It is recognized, of course, that the engineer also plays a primary role in the formation of exploratory units, drilling and spacing units, partial units, communitization agreements and other species of joint operating programs.

The History of Unitization
In 1948 Robert E. Hardwicke wrote a truly informative and interesting book called Anti-Trust Laws et al vs Unit Operation of Oil and Gas Pools, which was published by AIME as a service to the industry. Hardwicke defines, in form of questions, two problems which were facing the industry in 1925.
First, what could be done to increase efficiency in oil and gas development and production, or how could recovery of oil and gas be materially increased and the expense of operation materially decreased? Second, what could be done to prevent the haphazard development of new pools, with resultant over-production, waste, inefficiency, and the demoralization of markets and prices? The answer to both problems is, in a large measure, unitization.
Production From a Fractured Well With Well Inflow Limited to Part of the Fracture Height
Authors: Schulte W. M. 
Published: December 2007

Summary
A study is presented on the production behavior of hydraulically fractured wells in which gas or oil in the fracture enters the wellbore over a limited vertical interval, smaller than the fracture height. Such a limited communication interval between fracture and wellbore can be expected when the fracture is created from a deviated or a partially perforated well.
Type curves of the production behavior, derived with a numerical, single-phase simulator, show that in semiradial fractures with a limited communication interval, the early transient flow period exhibits the characteristics of a newly defined linear/radial flow regime. The characteristics of bilinear flow will be seen only when the fracture is in communication with the wellbore over the total fracture height.
An analytical derivation of the pressure response during pure linear/radial flow is given, and an analysis method that is capable of estimating fracture conductivity, effective well inflow interval, and fracture height has been developed by making use of the characteristics of linear/radial flow.
A small communication interval may also influence the long-term productivity of the well (especially a gas well) because of an increased non-Darcy flow effect near the communication interval. An expression for the expected skin value as a result of a limited communication interval is presented. The productivity of the well may be significantly reduced if the inflow interval is much smaller than the fracture height.
Propagation of Electromagnetic Waves Along a Drillstring of Finite Conductivity
Authors: DeGauque P. , Grudzinski R. 
Published: December 2007

Summary
An evaluation of the electromagnetic communication capability of a drillstring used to transmit data from the bottom to the surface of a well, or measurement while drilling (MWD), must take into account the finite conductivity and permeability of the drillstring. The choice of frequency is a compromise between a relatively fast transmission rate and a great depth of operation. Theory and experiments show that, because of the finite conductivity of the drillpipe, decreasing the frequency below a few hertz does not improve the communication because the current distribution along the string remains nearly constant.
The current distribution has been resolved numerically by a matrix formulation that takes into account the series or internal impedance of the drill, and a comparison with experimental results has been made.
Using Simultaneous Downhole Flow-Rate and Pressure Measurements To Improve Analysis of Well Tests
Authors: Guillot A. Y. , Horne R. N. 
Published: December 2007

Summary
The development of reliable spinner tools may help avoid much of the ambiguity that often accompanies well tests, resulting from interlayer flows through the wellbore. The use of both pressure and flow- rate changes, however, requires new methods of well test interpretation. Computer-based techniques have been developed for the simultaneous analysis of pressure and flow-rate measurements. This procedure consists of two key steps: (1) the nonlinear regression is achieved by calculation of the gradients of the response (with respect to the unknown reservoir parameters) in Laplace space and a numerical inversion; and (2) the variable flow rate is represented in terms of a superposition of many step changes, which was found to work better than a spline fit to the data. One problem was encountered when we attempted to analyze data in which the spinner stalled, causing a jump to zero flow rate.
The method shows great promise in that the degrees of freedom on the interpretation are greatly reduced, the wellbore storage effect disappears, and interlayer flows do not affect the results.
Use of Inverted-Emulsion Mud Proves Successful in Zones Susceptible to Water Damage
Authors: Trimble Glenn A. , Nelson M.D. 
Published: December 2007

Abstract
Extreme difficulties in well completions in Pennsylvanian age sands in Central Oklahoma led to the use of an inverted-emulsion mud for drilling-in, completion and workover operations in this area. This mud, containing about equal volumes of oil and water or water-base mud and emulsified by a modified wood product, has been employed successfully in over 150 operations over a six-year period. In zones that are susceptible to water damage, improved formation evaluation, better well completions and effective recompletion of damaged wells have been achieved. Mud is stored and re-used extensively. Testing and maintenance are relatively simple and inexpensive. The geological interpretation of formations has been adequate where the hole has been drilled with this mud. The mud offers no advantage in limestone or dolomite completion, and it may slow drilling rates in shale.

Early Well Completion Experience
In Central Oklahoma the majority of wells are in and the greater part of oil production is from sands of Pennsylvanian age. A number of formations are represented, of which the Springer and Hart sands are two of the better known.
Prior to 1953, the Mobil Oil Co. (then Magnolia Petroleum Co.) experienced severe difficulties in many well completions in various of these sands. Other operators in this area were having similar difficulties.
A characteristic experience follows. Drilling with a water-base mud (as was customary in this area), a well penetrated one or more Pennsylvanian age sands. At the time of penetration, drill-stem tests indicated fair producing rates. When completion of the well was attempted after further exposure of the sand to drilling mud or water, production was often much lower than indicated by the drill-stem test. In some extreme cases, no production could be obtained. In an outstanding example, oil flowed at 30 bbl per hour on drill-stem test, but could not be made to produce afterwards.
Well stimulation techniques, including acidizing and fracturing, were not effective in obtaining satisfactory completions. In some cases, attempted stimulation procedures, as employed, caused further decreases in production of oil.
Partitioning of Nonionio and Anionic Surfactant Mixtures Between Oil/Microemulsion/Water Phases
Authors: Graciaa A. , Lachaise J. , Bourrel Maurice , Osborne-Lee Irvin , Schechter Robert S. , Wade W. H. 
Published: December 2007

Summary
Mixtures of different surfactant types have been proposed for application in polymer/micellar flooding processes. In some cases, severe fractionation of such mixtures is found even in short core experiments. In this paper, a new theory of surfactant partitioning between phases is developed and tested. Polydisperse nonionic surfactants blended with an anionic surfactant are considered. Important parameters in the theory are the critical micelle concentrations (CMC's) of surfactant mixtures in water and the partition. coefficients of the surfactant between oil and water measured at total surfactant concentrations less than the CMC. From these simple experiments, surfactant fractionation in microemulsion systems can be modeled.
We also show that the fractionation of polydisperse ethoxylated nonionic surfactants between excess oil and water phases is not as severe in the presence of anionic surfactants as it is in systems containing only nonionic surfactants.
Field Results of Liner Rotation During Cementing
Authors: Lindsey H. E. , Durham K. S. 
Published: December 2007

Summary
Improving liner cementing has been a constant objective of the industry. Recent developments in rotating liner hanger technology have made this cementing technique applicable to more wells than before. Presented here is an analysis of 45 jobs done during 1 ½ years. The study examined mechanical success ratios as a function of liner size, depth, length, method of rotation, setting tool types, deviation, casing hardware (centralizers, scratchers, etc.), and bearing load. The results give the drilling and completion engineer a better understanding of the chances of a mechanically successful job.
Application of the Pressure-Derivative Function in the Pressure-Transient Testing of Fractured Wells
Authors: Wong D. W. , Harrington A. G. , Cinco-Ley H. 
Published: December 2007

Summary
A new technique is presented for the analysis of wells with a finite-conductivity fracture. The technique simultaneously uses the pressure and pressure derivative for cases with no fracture skin and no wellbore storage and for cases with fracture skin and wellbore storage during the bilinear-flow period. New type curves are presented and applied to three field cases. The paper concludes that use of the pressure derivative with pressure-behavior type curves reduces the uniqueness problem in type-curve matching and gives greater confidence in the results.
Analysis of Variable-Rate Well-Test Pressure Data Using Duhamel's Principle
Authors: Thompson L. G. , Reynolds A. C. 
Published: December 2007

SummaryThis work considers the use of Duhamel's principle to analyze pressure drawdown and buildup data when both bottomhole pressures (BHP's) and sandface flow rates are available. This analysis procedure uses Duhamel's principle to convert pressure data obtained when the sandface rate is variable to the equivalent pressure data that would be obtained for a constant sandface rate of production. The equivalent constant-rate pressure data then can be analyzed with standard procedures (semilog analysis or type-curve matching).
Phase Behavior of Several CO2/West-Texas-Reservoir-Oil Systems
Authors: Turek Edward A. , Metcalfe Robert S. , Fishback Robert E. 
Published: December 2007

Summary
The design of miscible CO2 recovery methods and the evaluation of laboratory CO2 coreflood and pilot field studies require knowledge of the phase behavior encountered in such processes and the ability to make reliable predictions. Because of the complexity of CO2/hydrocarbon phase behavior, experimental measurements are necessary as a basis from which to develop an understanding. In this paper, measured phase equilibria and volumetric properties are reported for several west-Texas-reservoir-oil/CO2 systems. Reservoir oils studied were from the San Andres, Grayburg, and Devonian Chert formations. Both static (single-contact) and multiple-contact measurements have been conducted in a visual fluid property cell. Static data cover a wide range of CO2 compositions and provide a general understanding of CO2/reservoir-oil phase behavior. Multiple-contact measurements in which the CO2-rich phase is repeatedly contacted with recombined reservoir oil (oil cycling) simulate phase behavior occurring at the flood front. Multiple-contact measurements in which the oil-rich liquid phase is repeatedly contacted with pure CO2 (CO2 cycling) simulate the phase behavior exhibited by residual oil near a CO2 injection well. The multiple-contact data cover narrow compositional paths encountered in displacement processes and serve as a basis for equation-of-state (EOS) evaluation. Phase behavior trends common to all systems are discussed.
Method for Laboratory and Field Evaluation of a Proposed Polymer Flood
Authors: Castagno Richard E. , Shupe Russell D. , Gregory M. Duane , Lescarboura Jaime A. 
Published: December 2007

Summary
The relevant components of a proposed polymer flood in the Tensleep reservoir of the Frannie Phosphoria-Tensleep Unit in Park County, WY, were investigated. Laboratory testing consisted of polymer injectivity, stability, retention, and effective viscosity measurements. On the basis of polymer viscosity and retention tests, a polysaccharide polymer was chosen over a Polyacrylamide polymer for extensive laboratory evaluation and field pilot tests. Field testing included injectivity, biological stability, and in-situ viscosity measurements. Pressure falloff tests following variable-rate injection of a polysaccharide polymer solution indicated the presence of a non-Newtonian, low-mobility bank. Even though good injectivity was obtained during injection of a 15% PV polymer slug, the proposed field project was not done. This was primarily because of low in-situ (reservoir) polymer solution viscosity and lack of proven microbial control in the near-wellbore region.
Down-Hole Injection of Butane to Control Paraffin Deposition in Pumping Wells
Authors: Lukehart Charles O. 
Published: December 2007

Abstract
Results of field tests indicate that butane can be injected easily and economically down the tubing-casing annulus of pumping wells. The quantity and frequency of butane injection varies with each well and, if injected properly, will effectively control paraffin deposition in the tubing and flow lines. Butane has the effect of increasing the solution capacity of the crude oil for the waxy substances being deposited.
In the 12 wells tested, a reduction in the cost of paraffin control by as much as 90 per cent was obtained, and in one well the annual reduction totaled $1,000. The expense necessary to install the surface equipment is $165.00 per well, and the injection process is performed by a pumper as a routine duty.
The injection of butane to control paraffin deposition at the present time is limited to wells that pump off or pump and flow off and to paraffin or mixed base crudes. Further study may indicate that the process can be utilized in other types of wells.

Introduction
Paraffin accumulation in tubular goods is a costly problem that has long been associated with crude oil production. One method for the control of this accumulation in pumping wells is the down-hole injection of a butane-crude oil mixture. The purpose of this paper is to outline the process and to indicate the saving that may be obtained in using this method for a more economical recovery of crude oil.

Solubility of Paraffin in Hydrocarbon Systems
Crude oil, as it originally exists in a reservoir, contains varying percentages of waxes, gums, resins and asphaltic materials which remain in solution until the solution equilibrium has been sufficiently disturbed; then these substances separate from the crude oil and form what is generally known as paraffin deposits. There are a number of factors involved in the separation and deposition of paraffin in crude oil wells; however, temperature decrease and loss of lighter fractions are the most important causes of solubility change and the resultant paraffin separation.