bluuebunny/crossref_metadata_2025_split huggingface dataset:
Shale Oil Nears Competitive Level with Domestic Petroleum
Authors: Miller Ernest P. , Cameron Russell J. 
Published: December 2007

Introduction
Advancements in oil shale technology, coupled with the sharply rising expense of finding and producing petroleum in the United States, have closed the economic gap between the two fuels. A realistic comparison of shale oil and petroleum costs presents certain problems, for the real meaning of posted crude prices is difficult to ascertain. Marginal crude-producing areas, discovered before the steep rise in exploration and producing costs of the past dozen years, are now being exploited. This report briefly reviews technical activities in oil shale and presents discussion and comparisons of shale oil production economics with crude petroleum prices.

Review of Technical Activities
Production of oil from shale has been an art and science in various parts of the world for more than a century. In the United States, prophecies of acute domestic petroleum shortages have been made periodically throughout this century. Previous flurries of activity in shale have soon diminished because of economic facts of life. Present efforts in shale development are the most significant to date and may finally indicate serious entry into the field - again because of economic facts.
Foremost among current and recent publicized oil-shale activity have been the multimillion-dollar project of the Union Oil Co. of California at Grand Valley, Colo.; the U. S. Bureau of Mines installation at Rifle, Colo., from 1944 to termination of that program in 1955; and the pilot plant retorting work being carried out by the Denver Research Institute (DRI) for the past several years. Most major oil companies hold oil shale land and represent varying degrees of interest and effort within their own organizations. Brazil has vast shale deposits and produces only 30 to 40,000 B/D of petroleum within her own borders - about 20 per cent of present controlled requirements.
Most current development work is directed toward the retorting phase of oil shale processing. USBM's mining work at Rifle is generally accepted as having adequately demonstrated that step to furnish basic information. Modern refining technology is such that shale oil can be processed to desired end products using processes with results and costs that are reasonably predictable.
The Propagation of Oil-Moving and Solubilizing Components of Broad Equivalent-Weight Sulfonate Systems in Micellar Floods
Authors: Chan Albert F. , Gupta Surendra P. 
Published: December 2007

Abstract
This paper presents a novel method of characterizing the broad equivalent-weight (BEW) sulfonates composed of two pseudosulfonate fractions that behave as the oilmoving and the sulfonate-solubilizing components. The terms quasi-monosulfonate and quasi-disulfonate are used to characterize these oil-moving and solubilizing components, respectively. Such a description of BEW sulfonates allows determination of sulfonate concentration in the flowing phases as well as the quantity adsorbed on the porous medium, and permits modeling of the sulfonate retention and transport behavior. Furthermore, the paper shows that the performance of a BEW sulfonate system in which a lower-phase microemulsion environment is predominant can be predicted by using independently measured input data, which include interfacial tension (IFT), fluid viscosity, and sulfonate retention isotherm.
A Numerical Study of Chemical Flooding—Comparison With Experiments
Authors: Van Quy N. , Labrid J. 
Published: December 2007

Abstract
This paper describes an enhanced oil recovery (EOR) model involving use of chemical additives. The model is as general as possible in light of present phenomenological knowledge. It takes into consideration diffusion, exchanges between fluid phases, exchanges between fluids and solids, and convection (including gravity, relative permeabilities, viscosities, interfacial tensions (IFT's), and mobility reduction by polymers).
Its main properties are (1) three-phase flow (aqueous, oleic, and microemulsion); (2) that each phase can be represented by a mixture of seven components; (3) overall flow is one dimensional (1D), but the sections of space considered may be constant or variable; and the porous medium may be heterogeneous.
In addition to its compositional nature, which is required for describing changes in phase properties, the model must also account for ionic environment, loss of chemicals, and capillary number distribution. For these reasons, it differs from conventional multicomponent models.
It is designed for simulating any EOR problem involving the addition of suitable chemicals to fluids to be injected continuously or in successive slugs. The model has been tested successfully by two-phase flow, four components (water, oil, polymer, and surfactant plus alcohol), and Winsor Type I environment experiments. It can be adapted to more and more complex phenomenological situations, depending on availability of data.
In-Situ Leaching of Crownpoint, New Mexico, Uranium Ore: Part 2—Laboratory Study of a Mild Leaching System
Authors: Vogt T. C. , Strom E. T. , Dixon S. A. , Johnson W. F. , Venuto P. B. 
Published: December 2007

Abstract
This paper describes laboratory leaching studies involving Crownpoint uranium ore samples and a mild leaching system. Batch leach tests with sodium bicarbonate solution and either high-pressure oxygen or low-pressure hydrogen peroxide gave qualitative data used to estimate leach rate and potential recovery. Using pseudo-first-order rate constants derived from the batch test data, ore leachability was characterized as fast, intermediate, or slow. It was observed that leach rates varied by a factor of 50 for samples taken from different areas at Crownpoint; samples from the same ore trend often varied by a factor of 10. Packed-column and core-leach tests with oxygen at pressures up to 800 psig (5520 kPa) provided more quantitative estimates of leach rate and uranium recovery. Batch test results were correlatable with leach rates and uranium recoveries in packed-column or core tests. In ore samples where uraninite was the predominant uranium mineral, leach rates and recoveries were high. In samples containing coffinite, leach rates were generally lower than those with uraninite. Very low leach rates and recoveries were encountered where coffinite was intimately associated with carbonaceous material. However, the slow leaching rates are not caused by differences in reactivity of coffinite and uraninite. Mineralogical studies before and after leaching using electron microprobe analyses indicated that exposed coffinite crystals are dissolved easily, but finely disseminated coffinite crystallites persist after leaching if they are encapsulated in the carbonaceous matrix. Slow-leaching ores that did not respond to the mild oxidant system are called "refractory."
An Improved Method for Measuring Fluid Loss at Simulated Fracture Conditions
Authors: McDaniel Robert Ray , Deysarkar Asoke Kumar , Callanan Michael Joseph , Kohlhaas Charles A. 
Published: December 2007

Abstract
A test apparatus is designed to carry out dynamic and static fluid-loss tests of fracturing fluids. This test apparatus simulates the pressure difference, temperature, rate of shear, duration of shear, and fluid-flow pattern expected under fracture conditions.
For a typical crosslinked fracturing fluid, experimental results indicate that fluid loss values can be a function of temperature, pressure differential, rate of shear, and degree of non-Newtonian behavior of the fracturing fluid.
A mathematical development demonstrates that the fracturing-fluid coefficient and filter-cake coefficient can be obtained only if the individual pressure drops can be measured during a typical fluid-loss test.
Well Test Analysis for Wells Producing Layered Reservoirs With Crossflow
Authors: Prijambodo R. , Raghavan R. , Reynolds A. C. 
Published: December 2007

Abstract
The pressure response of a well producing a two-layer reservoir with crossflow is examined. Virtually all studies on the response of a well in multilayered systems with crossflow claim that after a few hours of production these systems behave as if they are single-layer systems.
A careful examination of the early-time performance of a well in a reservoir with crossflow indicates that its behavior is remarkably different from that of an equivalent single-layer system and is influenced significantly by the degree of communication. It is important to understand short-time behavior, since the time span of virtually all pressure buildup tests encompasses the duration in which a layered reservoir with crossflow may not behave as if it were a single-layer system. Thus, interpretations of pressure buildup data based on single-layer theory can be erroneous.
In this study, we show that the flowing pressure response of a well at early times can be divided into three flow periods. The first period is one in which the reservoir behaves as if it were a stratified (no-crossflow) system. This period is followed by a transitional period. The response of the well during this period depends on the contrast in horizontal permeabilities and on the degree of communication between the layers. During the third period, the reservoir can be described by an equivalent single-layer system.
An examination of the time ranges of the various flow periods indicates that, unless tests are designed properly, most of the interpretable pressure buildup data would be measured during the time the well response is influenced by the transitional period.
The influence of the skin regions on the well response is examined. The significance of the estimate of the skin factor obtained from a pressure test is discussed. We show that the nature and the magnitude of the skin regions and the size of the reservoir determine the applicability of conventional semilog procedures to systems with interlayer communication.
Thermodynamic Modeling of Phase and Tension Behavior of CO2/Hydrocarbon Systems
Authors: Sahimi Muhammad , Davis H. Ted , Scriven L. E. 
Published: December 2007

AbstractThe gradient theory of inhomogeneous fluid is used to predict phase splits and compositions, interfacial composition profiles, and interfacial tension (IFT) of liquid-liquid, liquid-vapor, and liquid-liquid-vapor equilibria in binary and ternary mixtures of CO2 with propane and decane. The theory's input are the equation of state (EOS) of homogeneous fluid and the influence parameters of inhomogeneous fluid. An efficient computational algorithm is presented for simultaneously generating phase behavior, critical points, interfacial composition profiles, and tension between the phases. Most calculations are made with the Peng-Robinson EOS and the geometric mixing rule for the influence parameters. Use of other EOS and alternative schemes for choosing the influence parameters is explored.
Preliminary Experimental Results of High-Pressure Nitrogen Injection for EOR Systems
Authors: Ahmed T. , Menzie D. , Crichlow H. 
Published: December 2007

Summary
Miscible-displacement processes have generally been recognized by the petroleum industry as an important enhanced oil recovery (EOR) method. Nitrogen flooding has become an attractive method for economical EOR.1–3 Since no previous studies have been undertaken to observe miscibility conditions directly during their development in an oil reservoir, a research program was initiated to investigate experimentally the mechanism by which miscibility could be achieved in a reservoir model undergoing high-pressure nitrogen injection. Several experiments were conducted in a low-permeability, consolidated sandpacked stainless-steel tube 125 ft long and 0.435 in. in diameter. The apparatus was designed to allow sampling at selected locations along the core tube enabling researchers to investigate fluid behavior during the process.
A more-detailed representation of the nitrogen displacement process is formulated and the graphical chromatographic results are presented to illustrate the nitrogen miscibility in consolidated cores.
Scanning Electron Microscopy and Core Analysis for "Mini" CO2 Flooding Operations in the Hospah Formation of the Miguel Creek Field, McKinley County, New Mexico
Authors: Kupperman Glenn Stuart , Ward Brenda Marie , Blanks Gary L. 
Published: December 2007

Abstract
A combined laboratory evaluation that included scanning electron microscopy (SEM), energy dispersive spectrometry (EDS), X-ray diffraction, petrography, and core flow/permeability damage analysis was performed on core samples from the Hospah formation of the Miguel Creek field, McKinley County, NM. The objective of this study was to determine what type of recovery method would be the most beneficial and economical for a pilot five-spot, 8-acre plot.
The geologic evaluation of the core samples indicated tremendous lithologie differences in this formation. The rock types contained appreciable amounts of migrating clays (kaolinite and illite). Various degrees of pyrite, total clay content, and residual hydrocarbon saturation also were observed.
According to the operator, a conventional waterflood operation attempted during 1974–76 proved unsuccessful. This study indicates that the most likely reason was migratory fines. A foam fracturing technique also was attempted in June 1980 in the Miguel Creek field, with similar negative results. The conclusions from this study suggested that the use of a clay-stabilizing surfactant preflush in a "mini" CO2 waterflood could be an advantageous method of controlling migrating fines and swellable clays.
The Niobrara Gas Play: Exploration and Development of a Low-Pressure, Low-Permeability Gas Reservoir
Authors: Brown C.A. , Crafton J.W. , Golson J.G. 
Published: December 2007

Summary
The Niobrara gas play in eastern Colorado, northwestern Kansas, and western Nebraska is a successful economic development involving an integrated, interdisciplinary exploration and exploitation strategy. This comprehensive study of the Niobrara formation gives a concise description of methods for exploration, development, production and evaluation of the Niobrara reservoirs.

Introduction
In 1912, the Osborne and Dunn Co. encountered a strong flow of gas in the Niobrara formation while drilling the Goodland No. 1 well (Sec. 24-T8S-R40W) near the town of Goodland, KS. The well subsequently was plugged and abandoned. In the 1930's and 1940's, several small Niobrara gas wells were drilled in the Goodland field area by Industrial Gas Co. and others for local use only.
The Beecher Island field discovery well was Midfields No. 1 well (Sec. 14-T2S-R43W) in Yuma County, CO, drilled in 1919 by the Midfields Oil Co. It had estimated flow rates of up to 2 MMcf/D (57×10-3 m3/d) of gas. In the 1920's, four additional Niobrara wells were drilled in Beecher Island; however, connection to a pipeline could not be justified. By 1970, two of the four dry holes drilled to deeper formations had gas shows while penetrating the Niobrara formation.
Following a study in 1972 of the known gas shows in the Beecher Island field, Midlands Gas Corp. and Mountain Petroleum Corp. air-drilled six wells in Beecher Island. Five were completed without stimulation as producers and then were connected to a pipeline. The wells averaged 20 Mcf/D (565 m /d) each, which at $0.35/Mcf ($0.35/30 m) was uneconomical. However, they proved the existence of significant gas reserves.
Further investigation revealed many resistivity log anomalies and reported gas shows in the Niobrara of eastern Colorado and western Kansas. However, the play began when, in early 1974, the new high-quality foam fracture stimulation process was used for the completion of the Beecher Island field State 1-29 well (Sec. 29-T2S-R42W). The well had a prestimulation drillstem test rate of only 5.6 Mcf/D (160 m3/d). After the treatment, it had an initial potential of 721 Mcf/D (20×10 M /d), with a sustained rate of more than 150 Mcf/D (4250 m3/d).
The play now extends from Chadron, NE, and south to Kit Carson County, CO (Fig. 1). The major concentration of drilling remains in the original producing area in Yuma County, CO, and in Cheyenne and Sherman counties, KS. Since 1974, 919 Niobrara wells have been drilled, of which 454 are producers in more than 60 fields; 465 wells are dry holes. At this time, very few fields are developed fully.

Geology and Gas Origin
The Niobrara formation chalks were deposited during the last major transgression of the western interior Cretaceous sea, which extended from the Gulf of Mexico to the Arctic Ocean. The lower member of the Niobrara is the Fort Hays, which is 40 to 85 ft (12 to 25 m) thick. The upper member is the Smoky Hill, which averages 600 ft (180 m) (Fig. 2).
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Stimulation Design for Short, Precise Hydraulic Fractures
Authors: Smith Michael B. 
Published: December 2007

AbstractThis report discusses the philosophy, design, and implementation of small, precise, hydraulic fracture stimulations as applied in a micellar pilot in Salt Creek field, located in central Wyoming.Wellbore damage and relatively low permeability were resulting in low injection/withdrawal rates in the 1-acre [4046-m2] pilot in this field. Unchanged, these low rates would extend the pilot life by an unacceptable amount and also result in oil production rates too small for meaningful analysis. Accordingly, the decision was made to fracture-stimulate the pilot wells on the basis of reservoir stimulation, which snowed that the creation of very short (90 ft [29.5 m] tip-to-tip) fractures would not "harm" evaluation of the pilot's performance.Normal stimulation practices in this area would not give the control desired for this pilot situation to create a 90-ft-[29.5-m-] long fractures in a formation with a thickness of 100 ft [32.8 m]. The procedure that was developed consisted of measuring bottomhole treating pressure (BHTP) while pumping the pad, using these data to calculate the required sand-laden fluid volume, and then switching directly from pad to heavy sand concentration.A postappraisal of the treatments showed that BHTP measurement was necessary since the pressure varied from theoretical behavior for each well. After initial pressure increases that were predictable, a critical pressure was reached for each case and the value of this pressure (which governed slurry requirements) varied by 25% from well to well. The effects of the treatments also were evaluated with postfracture pressure falloff tests (PFOT). The stimulations performed generally were successful (fracture design/PFOT lengths of 156/146, 90/100, 134/150, and 55/20), confirming that it is possible to create short, controlled hydraulic fractures by using the procedure outlined in this paper.
Management's Use of Petroleum Engineering Evaluations
Authors: Houchin John M. 
Published: December 2007

Management is normally confronted with more profitable investments than it has funds available. It is only through accurate engineering evaluations that management can determine which proposed investments will result in the greatest company profit.

Why Engineering Evaluations Are Important
Engineering evaluations required and used by management must contain reserve estimates along with predicted rates of recovery and the economics of the proposal.
Several types of data are needed. The engineer needs knowledge of formation characteristics including types of rock, net pay thickness, porosity, permeability and unusual characteristics such as fractures. He must know about proration and allowables. Formation fluid characteristics such as initial gas in solution, reservoir volume factors, and relative permeability are important. Gas-oil ratios, pressure, and production performance history are important factors in the later life of a reservoir.

Profit Making Aspects
Management's interest in reserve estimates goes beyond the number of barrels of oil and rates at which it is produced. This interest includes evaluating the profit making aspects of a proposal. The most convenient and reliable yardstick for evaluating investments is the annual rate of return calculated by the discounted cash flow method. This method takes into account fluctuations in income over the life of an investment, the effect of federal income taxes, amortization and all other taxes and costs.
The rate-of-return concept calculated using predicted recoveries, and reserves from prospective properties and in the drilling of wildcats should be used to a greater extent, especially in these days of high lease costs in active areas of operations. A wiser selection of wildcat acreage will be made if consideration is given to rate-of-return studies from actual production experience in pools which have similar geologic formations and drilling and operating practices. The risk in leasehold and wildcat investments is being reduced appreciably by those managements who are looking at their engineering evaluations using comparative reservoir experience as well as the geological and geophysical justifications.
An Ultrasonic Global Inspection Technique for an Offshore K-Joint
Authors: Rose J. L. , Fuller M. C. , Nestleroth J. B. , Jeong Y. H. 
Published: December 2007

Abstract
The catastrophic collapse of several offshore platforms has spurred the development of nondestructive inspection techniques for offshore structures. Presented here are the concepts of an ultrasonic global inspection technique. Also presented are the results of feasibility studies conducted on 119−, 110−, and ⅓-scale model K-joint models using this technique for early detection of damage. The technique takes advantage of the geometry of tubular joints to give global ultrasonic coverage of a joint while employing a similarity-coefficient-based algorithm for actual damage detection. The data from the scaled models indicate a correlation between the value of the similarity coefficient and the extent of induced damage. The results are encouraging for further development of the technique for field use.