bluuebunny/crossref_metadata_2025_split huggingface dataset:
The Use of Transparent Three-Dimensional Models for Studying the Mechanism of Flow Processes in Oil Reservoirs
Authors: Van Meurs P. 
Published: February 2020

Published in Petroleum Transactions, AIME, Volume 210, 1957, pages 295–301.

Abstract
This paper describes a technique which permits visual observation of oil displacement processes throughout the interior of a porous structure as thick as two inches. A model having glass walls is filled with finely powdered glass. Such a model becomes completely transparent if the powdered glass pack is saturated with an oil having the same refractive index as the glass. When water or gas, with a refractive index different from that of the oil (glass) is injected, the model becomes opaque in the space occupied by the water (gas). Visual observation and photography of these displacement processes are thus rendered possible.
The following processes have been studied:Displacement of oil by water (linear drive) in a homogeneous formation, in a stratified formation.Water flooding (five-spot well pattern).Solution gas-drive process.Oil-bank formation.

Introduction
Most of the scaled model experiments heretofore carried out in the Koninklijke/Shell Laboratorium, Amsterdam, have been done in steel containers, saturated sand packs being used to represent the oil bearing formation. In such experiments, for instance those on the displacement of oil by water, the cumulative oil production was measured as a function of the cumulative water injection.
In order to interpret the measured production data, a need has for some time been felt for a means of observing visually what happens in the course of such experiments.
Some information of this type was obtained earlier by observing the water oil distribution in various cross sections of the sand after the conclusion of the experiment. However, the technique used did not guarantee that the fluid distribution remained undisturbed. Moreover, the procedure was somewhat elaborate and the information obtained limited. Therefore a new technique has been developed, which is described below.
The Development of Shaped Charges for Oil Well Completion
Authors: Poulter Thomas C. , Caldwell Blake M. 
Published: February 2020

Published in Petroleum Transactions, AIME, Volume 210, 1957, pages 11–18.

Abstract
A new approach to an old problem has made it possible to do in a relatively short period what has not been accomplished in the past three quarters of a century using strictly experimental methods.
A theoretical study was made of the underlying principles whereby a jet is formed by a shaped charge and of the mechanism of the penetration of the target by that jet. It was found that there are more than 10, and perhaps as many as 15 variables affecting the performance of the shaped charge. Only a few calculations are necessary to show that it is physically impossible to investigate all of these variables experimentally.
The shaped charge theory has been extended to include a previously littleunderstood mechanism in high explosive phenomena; namely, low order detonation. By superimposing a high order detonation on a zone already undergoing low order detonation, an appreciable improvement in performance is accomplished.
The development of a design whereby these phenomena are coordinated in such a way as to develop a jet which is tailored to meet the specific target requirement will be described in detail.
The shortcomings or even impossibility of strictly experimental techniques will be illustrated by a discussion of the development of a special-purpose explosive charge.

Introduction
In an article appearing in the May, 1888 issue of Scribner's' Magazine, Charles E. Monroe described his early experiments with gun cotton (Fig. 1) which led to his name being most frequently connected with our present-day shaped charge. Although the sunken letters or "cavities" in Monroe's gun cotton were not lined, they produced some penetration of an iron plate. The credit for the lined shaped charge, however, should rightfully go to R. W. Wood of the Physics Dept. of Johns Hopkins University, who was responsible for first discovering the fact that a metal liner in a cavity of explosive gave high velocity fragments and/or jets of metal.
This discovery was made by Wood inadvertently while investigating an accidental death resulting from an electric blasting cap.
Mechanics Of Hydraulic Fracturing
Authors: Hubbert M. King , Willis David G. 
Published: February 2020

Published in Petroleum Transactions, AIME, Vol. 210, 1957, pages 153–168. Paper presented at Petroleum Branch Fall Meeting in Los Angeles, Oct. 14–17, 1956.

Abstract
A theoretical examination of the fracturing or rocks by means of pressures applied in boreholes leads to the conclusion that, regardless of whether the fracturing fluid be of the penetrating or non-penetrating type, the fractures produced should be approximately perpendicular to the axis of least stress. The general state of stress underground is that in which the three principal stresses are unequal. For tectonically relaxed areas characterized by normal faulting, the least stress should be horizontal; the fractures produced should be vertical with the injection pressure less than that of the overburden. In areas of active tectonic compression, the least stress should be vertical and equal to the pressure of the overburden; the fractures should behorizontal with injection pressures equal to or greater than the pressure of the overburden.
Horizontal fractures cannot be produced by hydraulic pressures less than the total pressure of the overburden. These conclusions are compatible with field experience in fracturing and with the results of laboratory experimentation.

Introduction
The hydraulic-fracturing technique of well stimulation is one of the major developments in petroleum engineering of the last decade. The technique was introduced to the Petroleum Industry in a paper by J. B. Clark, of the Stanolind Oil and Gas Co. in 1918, and since then its use has progressively expanded so that by the end of 1955 more than 100,000 individual treatments had been performed.
A Method for Predicting Depletion Performance of a Reservoir Producing Volatile Crude Oil
Authors: Jacoby R.H. , Berry V.J. 
Published: February 2020

Published in Petroleum Transactions, AIME, Vol. 210, 1957, pages 27–33. Paper presented at Petroleum Branch Fall Meeting in Los Angeles, Oct. 14–17, 1956.

Abstract
Future depletion performance and ultimate oil recovery from reservoirs producing under volumetric control are often predicted with the aid of a material balance equation. when the reservoir fluid is very volatile, however, certain assumptions implicit in the use of the conventional methods are no longer valid. This is because laboratory differential vaporization test procedures do not adequately represent the reservoir depletion process and the performance of surface separation facilities. In such cases recovery of stock tank oil per unit of pressure decline can be predicted only from a detailed knowledge of the separator conditions and the over-all composition of the fluid entering the wellbore at each stage of depletion. Surface recovery is not simply related to the total quantity of liquid flowing into the well under reservoir conditions.
In order to improve predictions for reservoirs which produce volatile oils, a stepwise method of calculation has been developed. This method uses relative permeability data and multi-component flash calculations to predict oil and gas production as a function of reservoir pressure. Calculations are presented for a reservoircontaining a volatile crude oil, and predicted tank oil recovery by primary depletion is more than twice that predicted by conventional methods which are known to be adequate for ordinary black crude oils. Calculated maximum produced gas-oil ratio is less than one-fourth of the conventional prediction. Wellstream compositions have also been used to determine variation in stock tank oil composition and liquid content of the separator gas. This information is of particular importance for crude stabilization calculations and for design of gasoline plant facilities to recovery LAG and natural gasoline.
Performance Calculations for Reservoirs with Natural or Artificial Water Drives
Authors: Wooddy L.D. , Moore W.D. 
Published: February 2020

Published in Petroleum Transactions, AIME, Volume 210, 1957, pages 245–251.

Abstract
Water drives may be natural or artificial. For the case of a natural water-drive reservoir, the volume of water influx corresponding to reservoir pressure-production history may be calculated by means of the material balance-unsteady state equation. For the artificial water drive or pattern injection water flood, the material balance equation is sufficient to determine the reservoir pressure-production, injection history. However, for both cases to reliably predict reservoir performance, it is necessary to calculate the saturation distribution of the reservoir fluids at different stages of depletion.
This paper consolidates the various equations used to determine the performance of water-drive reservoirs into one approach that is applicable to any reservoir that has a natural water drive or is to be produced by water injection. The numerical procedure has been simplified considerably, and the solution is adaptable to either hand calculations or digital computer operation.

Introduction
A water-drive reservoir is one in which the predominant source of energy for production of oil results from the encroachment of water into the oil zone. The water drive may be either natural or artificial.
Water invasion takes place by expansion of water in the aquifer as a result of the pressure decline transmitted from the oil reservoir. Because water is practically incompressible, a natural water drive requires an extensive aquifer containing a volume of water many times the volume of oil in the reservoir. Provided the permeability of the formation is reasonably high, a moderate decline of reservoir pressure usually causes adequate water influx.
If the reservoir pressure decline becomes excessive because of low permeability or a high rate of production, part of the oil production may result from the liberation of dissolved gas which may cause excessive quantities of free gas to be produced along with the oil. In extreme cases, reservoir pressure may decline so rapidly as to cause the oil to be produced predominantly by dissolved gas drive, leading to abandonment of the reservoir before the advancing water has had a chance to flush the entire reservoir.
Fractional Balance Evaluation of Pressure Maintenance, Smackover Lime Gas Condensate Reservoir, McKamie-Patton Field, Arkansas
Authors: Schauer P.E. 
Published: February 2020

Published in Petroleum Transactions, AIME, Volume 210, 1957, pages 108–113.

Abstract
During the initial nine-year depletion of the McKamie-Patton pool gas-condensate reservoir, the pressure behavior and fluid analyses indicated pressure maintenance by gas injection would be attractive relative to continued pressure depletion. As a result, a gas cycling program was inaugurated in Aug., 1949, which has since maintained reservoir pressure. In order to evaluate the benefits of this program, the recoveries for natural depletion and for cycling followed by blowdown were determined by calculating the fractional balance of the molar quantities of vapor and liquid remaining in the reservoir and produced at the surface for various stages of depletion. The results of the investigation show theoretical ultimate recovery due to the cycling program will be 42 per cent greater than would be realized under pressure depletion type operation.

Introduction
The benefits of gas injection pressure maintenance programs in condensate reservoirs have been recognized and qualitatively described in several papers during the past 15 years. Some of these papers also describe methods for calculating the increased recovery realized from cycling; however, as a rule, hypothetical reservoirs were used as examples. This paper presents an evaluation of the pressure maintenance program for the McKamie-Patton condensate reservoir and includes a description of the fractional balance method employed to determine the benefits.

Reservoir Development and Characteristics
The McKamie-Patton pool, Lafayette County, Ark., was opened in June, 1940, with production obtained from the oolitic Smackover lime at a depth of approximately 9,300 ft. The structure is an anticline 8 miles long by 1 to 2 miles wide, and is one of many productive Smackover structures in Southern Arkansas.
Of predominant importance is the condensate-bearing gas cap portion of the reservoir, which covers approximately 4,000 acres, attains a maximum thickness of some 200 ft, and has an average thickness of 90 ft. Development of the cap was accomplished with 21 wells drilled on 160 acre spacing. An isopach map of the cap is shown in Fig. 1.
Microbit Dynamic Filtration Studies
Authors: Horner Victor , White M.M. , Cochran C.D. , Deily F.H. 
Published: February 2020

Published in Petroleum Transactions, AIME, Volume 210, 1957, pages 183–189.

Abstract
A laboratory study of the effects of physical and easily measured rheological properties upon dynamic filtration was carried out. The purpose was to determine the factors affecting dynamic filtration and thus learn how to control this important property.
The recommended procedure for determining the amount of fluid loss prescribed by API Code RP 29 "Field Procedure for Testing Drilling Fluids," is very useful for mud conditioning purposes, but inadequate for comparing filtration properties of different muds under dynamic conditions. Where dynamic filtration control becomes important for purposes such as logging and coring, other means of evaluating filtration properties are needed.
A special device and testing technique were developed to provide reliable data on filtration characteristics of different fluids under dynamic conditions. Liquid saturated rock samples were drilled with a microbit, and the amount of connate liquid displaced by the fluid being investigated was measured. The empirical testing procedure was considered reliable.
A large number of laboratory-prepared and field-mixed drilling fluids with a wide range of physical properties were studied. These properties included:shape of consistency curves,apparent viscosity,plastic viscosity,yield value,density, andAPI filter loss.
Test results indicate that very little, if any, trend could be established between changes in these fluid properties and dynamic filtration.

Introduction
During the process of drilling, excessive loss of liquid from the mud to the formation is undesirable for many reasons. Filtration can reduce production-zone permeability, cause sloughing of formations, affect electric log curves, and render the fluid data obtained from cores unreliable. Thus, it is very important that we gain a knowledge of the factors that control filtration.
It is generally agreed that in any type of filtration (static, dynamic, or combinations thereof), the mechanics of filtering depend in great part upon the composition of the fluid. Moreover, it is also true that the physical and rheological properties are influenced by the composition of the fluid. Indirectly, then, it was hypothesized that a relationship existed between dynamic filtration and physical-rheological properties, two effects of a common cause - fluid composition.
Potentiometric Analyzer Prediction of Pressure Distribution in a Gas-Condensate Reservoir
Authors: Bradley H.B. , Mullins L.D. 
Published: February 2020

Published in Petroleum Transactions, AIME, Volume 210, 1957, pages 397–398.

Introduction
Numerous articles have appeared in the literature citing the application of the potentiometric analyzer to cycling operations. Specific information obtainable by a potentiometric analysis, as noted by various investigators, includes:Pattern sweep efficiency for various injection and production rate programs.Injected fluid breakthrough time at production wells.Optimum production and injection rates.Prediction of injection and/or production well locations.History of advance of the injected-produced fluid interface.Ultimate life of the reservoir.Ultimate reservoir production.
This note describes a procedure for predicting pressure distribution in a gas-condensate reservoir by using the potentiometric analyzer to obtain potential distribution data on an analog model of the reservoir and then applying Muskat's equations. The method relates the volumetric weighted average datum pressure to the mean potential in the model.

Procedure
To predict the pressure distribution (assuming steady-state conditions) in a gas-condensate reservoir by potentiometric analysis, it is necessary first to establish the potential distribution in the potentiometric model of the reservoir. This can be done by measuring the voltage difference between a reference point (other than a production or injection well) and other points throughout the model for the particular injection-production rate schedule of interest and plotting these readings preferably on an isopachous map of the reservoir. Points of equal potential differences are then joined giving isopotential lines. To relate potential in the model to field pressure requires several operations.
Special Applications of Drill-Stem Test Pressure Data
Authors: Dolan John P. , Einarsen Charles A. , Hill Gilman A. 
Published: February 2020

Published in Petroleum Transactions, AIME, Volume 210, 1957, pages 318–324.

Abstract
This paper discusses how the following formation characteristics can be determined mathematically from drill-stem test pressure charts: true formation pressures, effective permeability of the entire section tested, well productivities, wellbore damage and possible detection of barriers (faults, pinchouts, etc.). This paper also presents a practical method for immediate determination of effective permeability and wellbore damage from successful double shut-in pressure tests. A list of recommendations for improving the reliability of drill-stem test pressures is also presented.

Introduction
A drill-stem test is a temporary completion designed to sample the formation fluid and to establish the possibility of commercial production. Early pressure recording devices were used merely to verify proper operation of the testing tool. Until recently the accuracy of the pressure gauges has been insufficient for any reliable quantitative use of the recorded pressures. In view of the need for more reliable formation evaluation and as a result of the recent interest in exploration work employing the concept of hydrodynamic entrapment, better pressure recording gauges are now in use. These devices can record pressure within 1 per cent above 1,000 psig and can detect differential pressures as low as 1/2 psig.
In addition to formation pressure, several other reservoir characteristics can be determined from DST charts; namely, well productivity, formation permeability, wellbore damage, and the possible existence of barriers (faults, pinchouts, changes in permeability, etc.). This paper presents a practical method to interpret DST pressure charts for formation pressures and many other reservoir properties, a method that has been developed in analyzing approximately 4,000 DST charts during the last five years. The techniques used are a composite of published articles on drill-stem testing together with well-known pressure build-up analysis methods.
The characteristics of the frequent exacerbator with chronic bronchitis phenotype and non-exacerbator phenotype in patients with chronic obstructive pulmonary disease: a meta-analysis and system review
Authors: wu jianjun , Xu Hong-ri , Zhang Ying-xue , Li Yi-xuan , Yu Hui-yong , Jiang Liang-duo , Wang Cheng-xiang , Han Mei 
Published: February 2020

Abstract
Objective: To investigate the clinical characteristics between the frequent exacerbator with chronic bronchitis (FE-CB) phenotype and the non-exacerbator (NE) phenotype among patients with chronic obstructive pulmonary disease (COPD). Methods: We searched CNKI, Wan fang, Chongqing VIP, China Biology Medicine disc, PubMed, Cochrane Library, and EMBASE databases for relevant studies published as of April 30, 2019. All studies that investigated COPD patients with the FE-CB and NE phenotypes and which qualified the inclusion criteria were included. Cross-Sectional/Prevalence Study Quality recommendations were used to measure methodological quality. RevMan5.3 software was used for meta-analysis. Results: Ten case-control studies (n=8848) were included. Compared with the NE phenotype, patients with the FE-CB phenotype showed significantly lower forced vital capacity percent predicted (FVC%pred) [mean difference (MD) -6.69, 95% confidence interval (CI) -7.73–-5.65, P<0.001, I2=5%], forced expiratory volume in one second percent predicted (FEV1%pred) (MD -8.50, 95% CI -11.36–-5.65, P<0.001, I2=91%), and forced expiratory volume in one second/forced vital capacity (FEV1/FVC) (MD -3.76, 95% CI -4.58–-2.95,P<0.001, I2=0%); in contrast, the quantity of cigarettes smoked (pack-years) (MD 3.09, 95% CI 1.60–4.58, P<0.001, I2=41%), COPD assessment test (CAT) score (MD 5.61, 95% CI 4.62–6.60, P<0.001, I2=80%), modified Medical British Research Council (mMRC) score (MD 0.72, 95% CI 0.63–0.82, P<0.001, I2=57%), exacerbations in previous year (2.65, 95% CI 2.32–2.97, P<0.001, I2=91%), body mass index (BMI), obstruction, dyspnea, exacerbations (BODEx) (MD 1.78, 95% CI 1.28–2.28, P<0.001, I2=91%), I2=34%), and Charlson comorbidity index (MD 0.47, 95% CI 0.37–0.58, P<0.001, I2=0] were significantly higher in patients with FE-CB phenotype. No significant between-group difference was observed with respect to BMI (MD-0.14, 95% CI -0.70–0.42, P=0.62, I2=75%). Conclusion: COPD patients with the FE-CB phenotype had poorer pulmonary function and higher CAT score, the quantity of cigarettes smoked (pack-years), frequency of acute exacerbations, and mMRC scores than those with the NE phenotype.
Patient Centred Medical Home (PCMH) transitions in western Sydney, Australia: A qualitative study
Authors: Metusela Christine , Usherwood Tim , Lawson Kenny , Angus Lisa , Kmet Walter , Ferdousi Shahana , Reath Jennifer 
Published: February 2020

Abstract
Objectives
Patient Centred Medical Homes (PCMHs), increasingly evidenced to provide high quality primary care, are new to Australia. To learn how this promising new healthcare model works in an Australian setting we explored experiences of healthcare providers in outer urban Sydney, where a number of practices are transitioning from traditional Australian general practice models to incorporate elements of PCMH approaches.
Design
We collected qualitative data from semi-structured interviews with healthcare providers working in a range of transitioning practices and thematically analysed the data.
Setting and participants
We interviewed 35 participants including general practitioners, practice managers and practice nurses from 25 purposively sampled general practices in western Sydney, Australia, seeking maximal variation in practice size, patient demographics and type of engagement in practice transformation.
Results
Interviewees described PCMH transformation highlighting the importance of whole of practice engagement with a shared vision; key strategies for transformation to PCMH models of care including leadership, training and supportive information technology; structures and processes required to provide team-based, data-driven care; and constraints such as lack of space and the current Australian fee-for-service general practice funding model. They also reported their perceptions of early outcomes of the PCMH model of care, describing enhanced patient and staff satisfaction and also noting fewer hospital admissions, as likely to reduce costs of care.
Conclusions
Our study exploring the experience of early adopters of PCMH models of care in Australia, informs the international movement towards PCMH models of care. Our findings provide guidance for practices considering similar transitions and describe the challenges of such transitions within a fee-for-service payment system.