bluuebunny/crossref_metadata_2025_split huggingface dataset:
The Effect of Oil on Foam Stability: Mechanisms and Implications for Oil Displacement by Foam in Porous Media
Authors: Nikolov A. D. , Wasan D. T. , Huang D. W. , Edwards D. A. 
Published: December 2007

ABSTRACT
Foam stability in the presence of Salem crude oil and pure hydrocarbons is investigated as a function of chain length of α-olefin sulfonates and electrolyte concentration. Interactions between aqueous foam films and emulsified oil droplets are observed using transmitted light, incident light interferometric and differential interferometric microscopic techniques. Foam destabilization factors are identified including the pseudoemulsion film tension and the surface and interfacial tension gradients. Results from foam-enhanced oil recovery experiments in Berea Sandstone cores are presented using the combined gamma ray/microwave absorption technique to measure dynamic fluid saturation profiles.
CO2 Foam Flooding Performance vs. Rock Wettability
Authors: Lescure B. M. , Claridge E. L. 
Published: December 2007

ABSTRACT
CO2 flooding projects have shown large potential for oil recovery but in many cases the volumetric sweep efficiency is greatly limited by gravity tonguing and/or viscous fingering. To reduce these effects foam could be used as an alternative to WAG CO2 injection.
Experiments on the CO2 foam process were conducted in a 1/4 5-spot reservoir model in order to investigate the effect of rock wetting state and total CO2 slug size on secondary and tertiary extra-oil recovery.
Laboratory model results show that the process is more successful in an oil-wet medium than in a water-wet medium due to larger surfactant adsorption in the water-wet medium. Also, requirements for optimal CO2 slug size are smaller than in the WAG process, with larger extra oil recovery for both secondary and tertiary floods.
Petroleum Engineering Manpower Supply: Results of the 1986 Survey
Authors: Bourgoyne A. T. 
Published: December 2007

Abstract
The purpose of this article is to report on the results of the SPE manpower survey conducted annually by the SPE Manpower Committee. This yearly survey asks educators from all the schools listed in SPE's Petroleum Engineering and Technology Schools book to tel 1 how many petroleum engineering undergraduates they have, how many graduates they had last year, what their ability to get jobs were, and what they predict their graduates' ability to find jobs will be in the future. For those graduates reporting jobs, the sector of the industry in which the jobs were found is also reported.
This year, 20 of the 50 schools we solicited returned the surveys. Exactly half of the surveys went to U. S. schools; 12 of those were returned. In addition, one of five schools listing petroleum engineering options returned the survey. Other sources of information were used whenever possible to fill information gaps. SPE's annual Petroleum Engineering and Technology School s directory, based on surveys conducted by the Education and Accreditation Committee, is the best source of annual information on the size of the freshman, sophomore, junior, and senior classes.
This year's survey showed that the petroleum engineering job market was the worst it has been since the SPE Manpower Committee began collecting statistics in 1978. Only 29 percent of graduates seeking a job reported finding a job by the time of graduation. About 69 percent of the jobs found were with major oil companies. All other sectors of the petroleum industry showed a greatly reduced on-campus recruitment. Major oil companies also reduced on-campus recruitment significantly, but to a much lesser extent than the independent producers, pipeline companies, service companies, drilling contractors, government, consultants and financial institutions.
Computer Vision for Fundamental Studies in Porous Media: Part I–2-D Image Acquisition and Processing for Microscopic Distribution of Oil, Water, and Pore Space Networks
Authors: Yadav G. D. , Macdonald I. F. , Chatzis I. , Dullien F. A. L. 
Published: December 2007

ABSTRACT
Microscopic studies of the distributions of oil and water and of their networks in the pore space, at various relative saturations, are of fundamental importance in understanding migration, distribution, entrainment and mobilization of oil in the context of a particular (enhanced) oil recovery method. There has been an upsurge of interest in quantitative image analysis of pore morphology from two-dimensional thin and polished sections; however, the subject of determining the three-dimensional geometry and topology of multifluid networks has not been dealt with at all.
We have developed novel techniques for studying the irregular, interconnected pore space network of reservoir rocks. An image acquisition and analysis system incorporating a micro-computer, video equipment and microscope has been built for these studies. We are in the process of extending the methodologies to study the separate wetting and nonwetting phase networks which exist during immiscible displacement processes. As a necessary first step, we have developed the interactive computer-based technique described here to extract individual phase images, e.g., water, oil, and rock, from images containing all these phases together. The two-dimensional serial section data are accumulated on video tapes in which, for a particular cross-section, images of wetting phase, non-wetting phase and all phases together are recorded and processed by the software developed by us. Image segmentation is done interactively with the aid of the operator. The criteria used in the image segmentation are discussed. The procedure and results are illustrated by analysing microscopic data collected for oil-water immiscible displacement in Berea sandstone during primary drainage. The processing of the two-dimensional images, including the methods of filtering, thresholding, edge-extraction, and combining images, is described.
Fracturing Treatment Quality Control: Results of a Three-Year Survey
Authors: Dees J. M. , Coulter G. R. 
Published: December 2007

Abstract
During 1983, 1984 and 1985, Sun Exploration and Production Company personnel surveyed on-site job performance on fracturing treatments throughout the USA.
The number of fracturing related problem jobs and the types of problems encountered are summarized in the survey results. Proppant samples were taken on many of the jobs included in the survey and analyzed as to mesh size specifications.
Specifically, more than 1000 frac jobs were evaluated in the survey. Problems occurred on approximately 20% of those jobs. The types of problems were analyzed and divided into service company related and non-service company related. From this analysis, the various service companies were evaluated as were the types of problems experienced. The non-service company related problems were also assessed.
Of 403 proppant samples, approximately 41% failed API mesh size specifications and 28% failed a less rigid mesh size specification set by Sun. The effect of this quality control problem is demonstrated with fracture flow capacity data.
From this survey, Sun has been able to identify and address fracturing quality control problems.
Threaded Connection Qualification Procedures Utilized for an Ultra-Deep, High-Pressure Gas Well
Authors: Minge J. C. , Pejac R. D. , Asbill W. T. 
Published: December 2007

ABSTRACT
This paper describes the premium connection qualification program used to qualify three (3) different connections for the production tubular strings used in an ultra-deep, high pressure gas well. A total of eight (8) connection types were tested during the program. Four (4) connections failed to meet the program's acceptance criteria. Full-scale test procedures and the data acquisition system used to collect, store, reduce, and plot strain gauge data while testing are discussed.
Makeup Torques for API-Type Round Thread Casing Connections With Non-API Weights, Grades, and Coupling Diameters
Authors: Hainey M. F. 
Published: December 2007

ABSTRACT
Make-up torque calculation procedures are presented for API-type round thread casing connections with non-API weights, grades, and coupling dimensions--connections which are commonly used in the industry but for which there is not an industry-published reference on make-up procedures. Included are a simplified version of the API procedure for calculating optimum make-up torques that may be used for non-API weights and grades of casing, a procedure for adjusting make-up torques for connections with oversize or special clearance couplings, and a procedure for calculating make-up torques for connections used in sour service.
A New Nozzle System To Achieve High ROP Drilling
Authors: Chia R. , Smith R. 
Published: December 2007

ABSTRACT
Given the various controllable drilling parameters, hydraulic power is perhaps the most versatile, and yet least understood effect. The primary usage of hydraulic energy and the drilling fluid as applied by rock bits is to clean the wellbore bottom and the teeth of the bit. For decades, hydraulic energy had been determined according to first order approximations of jet effects, such as impact force and/or hydraulic horsepower. These factors were useful to the drilling personnel but did not provide enough information for the engineer to intentionally design the hydraulic system to clean the bit and wellbore. In order to achieve the cleaning objectives, one needed to know not only the jet velocity but also its interaction with the bit body and the rock formation. The challenge to find the stagnation zones, the erosion rate on the different parts of the bit, and the movement of the rock chips became apparent.
The paper discusses a computer simulation study of the fluid characteristics at each point of importance on the bit, which has been utilized to design a new nozzle system. This study consists of mini-extended nozzles, stabilizer pads, and a center nozzle. The means of designing an optimized hydraulic system, including laboratory work and the statistical analysis of field run data for correlation between theory and practice is presented. This integrated nozzle configuration increased the overall rate of penetration an average of 18 percent based upon 134 mini-extended nozzle bit runs. The drilling costs were cut inherently due to the penetration rate increase.
Relating Gulf Coast Sand/Shale Statistics to Petrophysical Properties as Seen by Seismic
Authors: Burns C. S. 
Published: December 2007

Abstract
Over 1250 wells on the Cenozoic continental shelves of Texas and Louisiana have been digitized and entered into a log-analysis program. The velocity-density functions of sand and shale have been statistically cataloged both vertically (via geopressure) and regionally. The major criteria for defining the lateral extent of the trend boundaries were based on shale analyses and velocity-density maps. The Plio-Pleistocene depocenters statistics from this trend illustrate the majority of the classification schemes. The velocity and density contribution to the total reflection coefficient varies dramaticly from Miocene to Pleistocene. The exclusion of density, or its approximation from velocity, results in reflection coefficients which are unreliable for seismic interpretation. By incorporating geologic age, shale percentage, geopressure, and depth of burial, with an approximate expression for the reflection amplitude as a function of incident angle, the ability to predict lithology from seismic data is greatly enhanced.
Provided the P-wave velocity and density are known, the incident-angle dependent amplitude variation becomes a function of the difference in the two Poisson's ratios at a formation boundary. Thus seismic estimates of Poisson's ratio can be obtained, which can aid in the determination of fracture pressure and lithologie characterization of reservoirs.
Geologic Controls on Producibility at Clear Creek Field, Uinta County, Wyoming
Authors: Alexander W. G. 
Published: December 2007

ABSTRACT
Production from the eolian Nugget formation at Clear Creek field in the southwest Wyoming thrust belt is controlled in large part by permeability anisotropy emplaced at the time of deposition and subsequent reorientation of the formation as a result of folding. Maximum permeability in this eolian system occurs in and parallel to dune slip-face bedding planes. Vertical permeability across less porous interdunal deposits ranges from two to three orders of magnitude less than the maximum permeability in the dune deposits. At the time of Nugget deposition the dune orientation was predominantly northwest-southeast with the slipfaces dipping to the southwest, giving a northwest-southeast orientation to the axis of maximum permeability (Kmax axis). This Kmax axis was curved or bent during subsequent folding of the sediments, giving it various orientations depending on structural position. Higher gas oil ratios are observed at Clear Creek where the separation of oil zone perfs from the gas cap along the Kmax axis is smaller. These higher gas oil ratios result as gas is preferentially "channeled" along the slipface bedding planes to the oil zone perfs. In situations as at Clear Creek, where the oil zone is thin and a gas cap is present, oil zone completions must be located where the Kmax axis is near horizontal, thus maximizing the separation of perfs from the gas cap. This reduces the "channeling" of gas along the Kmax axis and maximizes oil zone recoveries. Another parameter affecting producibility is rock deformation due to faulting. Faulting in the Nugget results in the development of intense gouge zones along and adjacent to fault planes. These gouge zones represent potential barriers to flow.
Friction Losses in Vertical Tubing as Related to Hydraulic Pumps
Authors: Brown F. Barton , Coberly C.J. 
Published: December 2007

Abstract
In a previous paper, the authors showed that the viscosity of the fluid in a well varies in an exponential manner with well depth due to the temperature and pressure gradients of the well. A viscosity gradient, , was introduced as a means to integrate the friction loss in the tubing string of a well.
This paper presents the accepted relations for friction loss in circular sections in a form suitable for oilfield use.
Hydraulically operated pumps may also involve the flow in an annulus between a large and small-diameter tubing or between a tubing and casing. Where annular flow is involved, the inner tube usually will be eccentric to the outer tube or casing. The available literature was reviewed on this subject, and correction factors proposed by several different writers were combined in the friction loss relations for both laminar and turbulent flow.
To simplify calculations in annular sections, equivalent diameters are introduced that take into consideration these factors. These diameter may then be used in the normal friction loss relations for circular section. They are tabulated for the more common combinations of tubing and casing sizes.
Charts and nomographs are presented. Together with the nomographs of the previous paper, they enable the petroleum engineer to quickly estimate tubing sizes and to determine the friction losses in a given system.

Introduction
In an ordinary hydraulic system, the conduit is normally circular in cross section, the viscosity of the fluid and the specific gravity are constant and the static head probably is small. In a hydraulically operated oil-well pumping system, the conduit may be either circular or annular. Also the fluid is subjected to a high static head and large temperature gradient and, as a result, viscosity and specific gravity will vary with well depth. Because of this large variation of viscosity, the flow in the tubing strings may be both turbulent and laminar. Therefore, the calculation of friction losses in hydraulic pumping installations poses a number of problems not encountered in ordinary hydraulic systems.
Tax Regime and the Development of the Petroleum Industry in Australia
Authors: Robson R. J. , Widmer G. R. 
Published: December 2007

ABSTRACT
Australia is a Federation of States with responsibility for the development of mineral resources being vested in the sovereign States, except in offshore regions where the Commonwealth has jurisdiction. Thus, different taxation regimes may apply in different geographical regions. The paper will outline the development of the tax regimes applying in Australia from the onset of large scale petroleum production in 1969 to the present day.
The paper will briefly trace the "boom and bust" syndrome and deal with the benefits of providing a stable pricing and fiscal environment for the exploitation of hydrocarbons. The paper will also describe the income taxes, production levies, and royalties which are found in the oil and gas sector and make up the Government's taxation receipts. It will also indicate how changes in the fiscal mix will effect the future course of petroleum exploration in Australia.
To demonstrate the variability of different taxation regimes that exist, economic models have been constructed to show the taxation effects on the prospectivity of different regions and the profitability of different sized oil fields. These will be evaluated in relation to the cost of development and remoteness from infrastructure and markets, and the results presented in graphical form. Conclusions as to the appropriate form of regime will be drawn.
Australia's 70% self-sufficiency in light crude oil is expected to decline to 30% in the 1990's in the absence of further large discoveries. Continuation of stable taxation and pricing policies is seen to be necessary if this decline in self-sufficiency is to be arrested.
Specific Mixing Energy: A Key Factor for Cement Slurry Quality
Authors: Orban J. A. , Parcevaux P. A. , Guillot D. J. 
Published: December 2007

ABSTRACT
In this paper, the relationships between cement mixing and cement slurry quality are investigated. Laboratory mixing conditions, using a high shear mixer, are compared to field mixing conditions, including conventional jet mixer, recirculating type mixer and batch mixer.
All the mixing conditions can be reduced according to a single parameter, the specific mixing energy, that allows the comparison of laboratory and field mixing with confidence.
Typical cement slurry properties, like rheology, free water, fluid loss, thickening time and compressive strength, are measured as a function of the specific mixing energy. All these properties improve when the specific mixing energy increases. The efficiency of cement additives, like dispersants and fluid-loss agents, is also found to vary significantly with the energy. A tentative explanation is proposed through a mechanism of particle deflocculation and dissolution, leading to an increase in the available specific surface area.
Optimal slurry properties are obtained at specific energies close to that imparted by a laboratory mixing following the API Specification 10. The specific mixing energy parameter has been quantified for different pieces of typical field equipment and conditions, from mixers to centrifugal and high pressure positive displacement pumps, and pumping through orifices. Current standard field practices can represent as low as 10 %, of the specific energy imparted by the API procedure. Comparative measurements in the field have shown that the cement slurries mixed then in these conditions have considerably poorer properties than the same ones mixed in the laboratory.
As a consequence it is recommended to increase the field specific mixing energy to a value as close as possible to the API one. This provides optimum slurry quality and good similarity between laboratory and field conditions.
Nitrogen Management at the East Binger Unit Using an Integrated Cryogenic Process
Authors: Emmons Fred R. , Hudspeth Lon D. , Clancy James P. , Zornes David R. , Philcox John E. 
Published: December 2007

ABSTRACT
The East Binger Field located in Caddo County, Oklahoma had an expected primary recovery of only 10.7%. After extensive reservoir, laboratory, and model studies, a plan of unitization was approved and an inert gas miscible displacement project was initiated in 1977. Unanticipated operational problems, such as leaks in casings, tubing and packers, plugging of low permeability sand, and other problems were analyzed and solved. Oil and gas production to date is consistent with the predictive models. An anticipated problem of inert gas breakthrough has been handled to date by planned interim methods.
In 1984, as a result of engineering and economic studies of several viable alternatives, a decision was made by the East Binger Unit (EBU) to switch to a nitrogen management concept. Under construction, with a late 1986 startup date, is a nitrogen management facility which will replace the existing inert gas supply system as well as replace the interim method of handling produced gas. The facility which is integrated to reduce capital, energy and other operating costs, will provide cryogenically-produced nitrogen from both nitrogen rejection and air separation, 985 Btu/SCF [3.48 × 104 MJ/m3] residue gas, pipeline quality natural gas liquids and 18,000 MSCFD (thousand standard cubic feet per day) [5.1 × 105 m3/D] of 5,000 psig [3.45 mPa] nitrogen. With nitrogen management, higher hydrocarbon recoveries and lower lifting costs are expected.
Simulation of Unstable Miscible Displacements by Finite Element Method
Authors: Peters E. J. , Kasap E. 
Published: December 2007

ABSTRACT
A modified finite element method was developed to simulate unstable miscible displacements in heterogeneous porous media. The modification was to evaluate the transport properties at the center of the elements, instead of at the numerous gauss points. This averaging procedure reduced the computational time by as much as thirty percent compared to the standard finite element method while still retaining the fingering behavior of the unstable displacements. Further, the modified method showed less grid orientation effect and resulted in a more robust numerical model than the standard finite element method.
Studies of Gas Injection Into Oil Reservoirs by a Cell-to-Cell Simulation Model
Authors: Pederson K. S. , Fjellerup J. , Thomassen P. , Fredenslund A. 
Published: December 2007

ABSTRACT
Injection of various gases into two different North Sea reservoir oils has been simulated using a cell to cell model. It is shown that ternary diagrams are insufficient to represent the mixing processes which take place in a petroleum reservoir into which gas is being injected. New criteria for evaluating the results of a cell to cell calculation are suggested. The highest recoveries are obtained when a miscible drive is established. However, also in cases where miscibility is not achieved, a marked enhancement of the oil recovery may be possible.
An Artificial Intelligence Approach to Lithostratigraphic Correlation Using Geophysical Well Logs
Authors: Olea R. A. , Davis J. C. 
Published: December 2007

ABSTRACT
Computer programs for lithostratigraphic correlation of well logs have achieved limited success. Their algorithms are based on an oversimplified view of the manual process used by analysts to establish geologically correct correlations. The programs experience difficulties if the correlated rocks deviate from an ideal geometry of perfectly homogeneous, parallel layers of infinite extent.
Artificial intelligence provides a conceptual basis for formulating the task of lithostratigraphic correlation, leading to more realistic procedures. A prototype system using the "production rule" approach of expert systems successfully correlates well logs in areas of stratigraphic complexity. Two digitized logs are used per well, one for curve matching and the other for lithologic comparison. The software has been successfully used to correlate more than 100,000 ft [30 480 m] of section, through clastic sequences in Louisiana and through carbonate sequences in Kansas. Correlations have been achieved even in the presence of faults, unconformities, facies changes, and lateral variations in bed thickness.