bluuebunny/crossref_metadata_2025_split huggingface dataset:
Use of MWD for Turbodrill Performance Optimization as a Means To Improve ROP
Authors: de Bruijn H. J. , Kemp A. J. , van Dongen J. C. M. 
Published: December 2007

Summary
Field tests were carried out to monitor the performance of turbodrills driving polycrystalline-diamond-compact (PDC) bits. Separate tests with miid-pulse measurement-while-drilling (MWD) tools involved measurement of the rotational speed of the bit and downhole torque. The results show that turbodrills are not always operated at the manufacturer's claimed maximum efficiency, resulting in disappointing rates of penetration (ROP's). On the basis of observed reduction in turbodrill runaway speed from the manufacturer's value, it is estimated that thrust-bearing friction can consume up to 50% of the net turbodrill power output.
In an 8½-in. [21.6-cm] hole, improvements in ROP of up to 100% could be obtained by use of the measured bit rotational speeds to monitor power output of the turbodrill. It was difficult to control bit rotational speed from the weight on bit (WOB), however, at the low average WOB's necessary for current PDC bit designs.
It was apparent that the measurement of downhole torque has limited field application because no distinction can be made between true reactive torque at the bit and additional torque from the turbodrill's thrust bearings and stabilizers.
The possible effect of flow-rate variations through the turbodrill during negative mud pulses was investigated with a flow loop. This proved to be insignificant.
Low-Toxicity Oil Muds: A Knowledge of Downhole Rheological Behavior Assists Successful Field Application
Authors: Bailey T. J. , Bern P. A. , McEwan F. 
Published: December 2007

Summary
The introduction of oil-based drilling fluids has led to significant improvements in drilling efficiency for many North Sea operations. The original formulations that were based on diesel are generally being replaced by the lower-toxicity mineral oils. One factor crucial to the successful application of mineral oils has been a knowledge of their downhole rheological characteristics. This paper describes a purpose-built viscometer capable of simulating realistic downhole temperature (300°C [572°F]) and pressure (100 MPa [1,000 bar]) conditions. Results from this study are used to indicate how surface-fluid rheologies can be tailored to provide adequate downhole viscosities, thus reducing total system pressure losses.
Numerical Simulation Results for the Electrical Heating of Athabasca Oil-Sand Formations
Authors: Hiebert A. D. , Vermeulen F. E. , Chute F. S. , Capjack C. E. 
Published: December 2007

Summary
Electrical preheating has been proposed as a method of overcoming many of the problems inherent in using a steamdrive in very viscous oil reservoirs—such as the Athabasca oil sands of Alberta, Canada. A numerical simulator was developed to study the process of electrically heating oil reservoirs consisting of several layers with different electrical resistivities. This simulator was used to study the effects of electrode placement on the final temperature contours resulting from electrically heating realistic reservoirs. Three cases illustrating the development of a hot-oil communication path low in the formation are described.
Calculation of High Temperature Crude-Oil/Water/Vapor Separations Using Simulated Distillation Data
Authors: Langhoff J. A. , Wu C. H. 
Published: December 2007

Summary
High-temperature crude-oil/water/vapor separation takes place in steamflooding and in-situ combustion processes. It also takes place in hydrocarbon recovery from deep volatile oil and condensate reservoirs. A practical procedure that uses the Holland and Welch method and sirilulated distillation data was developed to calculate crude-oil/water/vapor separations at 387 and 456°F [197 and 236°C]. The overhead yields obtained from the calculations were expressed as a function of the steam distillation factor. The Vw/Voi results were compared with laboratory crude-oil steam distillation data. The approach satisfactorily predicted the overhead yields of 13 out of 16 crude oils with an average error of 12% (±3.6% in yield). This is within experimental error of crude-oil steam distillation.
Twelve pseudocomponents of crude oils were selected and characterized with simulated distillation data for the calculations. The physical properties of the pseudocomponents were determined from existing correlations and from matching laboratory steam distillation data. The use of simulated distillation data eliminates the uncertainty and assumptions normally involved in the selection of crude oil pseudocomponents with U.S. Bureau of Mines distillation data, and thus improves the reliability of the proposed computational approach.
The proposed approach eliminates the need to conduct experimental steam distillation tests if simulated crude oil distillation data are available. It is easy and fast to calculate the overhead yields ahd densities without use of the equation of state (EOS) and uncertain pseudocomponent critical properties and interaction parameters. The proposed approach will provide useful information for the numerical simulation and design of thermal recovery processes and for the prediction of hydrocarbon recovery from high-temperature volatile oil and condensate reservoirs.
A Composite System Solution in Elliptic Flow Geometry
Authors: Obüt S. Tanju , Ertekin Turgay 
Published: December 2007

Summary
A new well-test analysis technique that can be used in locating the flood-front position during secondary and/or tertiary recovery processes with the data taken on vertically fractured injection wells is described. In the development, an infinite-conductivity vertical fracture was assumed, together with the assumption of a stationary position for the flood front during the testing period.
Comparative Evaluation of Vertical and Horizontal Drainage Wells for the Degasification of Coal Seams
Authors: King Gregory R. , Ertekin Turgay 
Published: December 2007

Summary
A two-phase, single-well, numerical simulator capable of modeling the performance of either vertical or horizontal wells (drilled from a shaft bottom) has been developed. For vertical wells, the model allows for the prediction of postfracture performance. The hydraulically induced fractures can be specified as either infinite conductivity or finite (constant) conductivity, so that conventional, as well as massive, treatments can be modeled. Although the simulator allows for multiple fracture wings, only the classic, two-wing, hydraulic fracture is considered in this paper.
For coal seams, the formation to be modeled is a dual-porosity reservoir. The natural fracture network of the coal seam (the butt and face cleat) has been assigned an effective porosity and permeability. A time-dependent, quasisteady-state sorption term has been included to describe the phenomenon of gas desorbing from the formation matrix and diffusing into the fracture network.
The model was used to sift through the many parameters associated with the two production schemes to determine those that affect production most significantly. Where possible, these parameters, along with their effects, are put into dimensionless form. Type curves for estimating recovery were generated from these dimensionless groups. Finally, a comparison between the performance of vertical and horizontal boreholes was made with actual field data.
Review of U.S. Oil and Gas Production 1964
Authors: Lindsly R.R. 
Published: December 2007

Editor's Note: R. R. Lindsly, with Phillips Petroleum Co. in Bartlesville, Okla., heads one of SPE's hardest-working but least-publicized standing committees. As chairman and domestic vice-chairman of the Society's Production Review Committee for 1965, Lindsly has collaborated with Foreign Vice-Chairman James E. Fender, of Mobil International Oil in New York City, to gather vital data from throughout the Free World for inclusion in IOSA's INTERNATIONAL OIL AND GAS DEVELOPMENT, YEAR BOOK 1965, a two-part volume covering worldwide exploration and production during 1964. The following article by Lindsly will appear in Part 2 on Production, expected to be available for sale in early December.

Introduction
The petroleum industry supplies approximately 74 per cent of the nation's energy requirements, and its domestic capital expenditures total more than $6 billion annually. The producing segment of the industry accounts for around 65 per cent of these capital expenditures, and domestic production amounts to approximately 80 per cent of the nation's liquid raw material supply. The producing industry, which is important to national security, had reserve producing capacity Jan. 1, 1965, of approximately 2.8 million B/D of crude oil and natural gas liquids, based on IPAA estimates. The productive capacity of natural gas on Jan. 1, 1964, as estimated by NPC in its 1965 report, indicates 57.7 billion cu ft/day of capacity over and above the average production for 1963.Total petroleum demand in 1964 averaged 11.06 million B/D, up 302,000 bbl, or 2.8 per cent from 1963.Gasoline, which makes up approximately 42 per cent of demand, experienced a healthy 4.2 per cent increase. Total petroleum supply in 1964 averaged 11,071,000 B/D. of this total, domestic crude production (69.2 per cent of supply) averaged 7,664,000 B/D, up 1.6 per cent; natural gas liquids production (10.4 per cent of supply) averaged 1,147,000 B/D, up 4.5 per cent; and imports of crude and products (20.4 per cent of supply) averaged 2,260,000 B/D, up 6.5 per cent from 1963.Demand for natural gas continued its upward trend in 1964 as reflected by production, which totaled 15.3 trillion cu ft, or 5.5 per cent increase over the 14.5 trillion cu ft produced in 1963.Fig. 1 shows supply trends of petroleum and natural gas for the past 10 years (1955 to 1964).

Reserves
To supply the ever-increasing demand for petroleum and natural gas, adequate reserves must be maintained through continuous exploratory efforts, development drilling, and improved recovery techniques. Therefore, it is pertinent to note the changes in underground inventory during 1964.Proved reserves of crude oil at year-end 1964 stood at 31 billion bbl, up less than 0.1 per cent from the previous year. This upturn, though slight, contrasts with a net decrease in crude reserves in three of the four previous years.
JPT
P. 889ˆ
Rapid Measurement of Minimum Miscibility Pressure With the Rising-Bubble Apparatus
Authors: Christiansen Richard L. , Haines Hiemi Kim 
Published: December 2007

Summary
The minimum miscibility pressure (MMP) for a gas/oil pair can be measured within 1 hour with the rising-bubble apparatus (RBA). Development of miscibility between a gas bubble and an oil can be observed visually. The measurements of the MMP with the RBA compare favorably with those based on slim-tube experiments and predictions from phase-behavior studies.
Prediction of CO2 Flood Performance: Interaction of Phase Behavior With Microscopic Pore Structure Heterogeneity
Authors: Dai K. K. , Orr F. M. 
Published: December 2007

Summary
This paper describes simulations of the effects of microscopic heterogeneity present in rock pore structures or resulting from high water saturations on the performance of one-dimensional (1D) CO2 floods. In the simulations, microscopic heterogeneity was represented by dividing the nonaqueous portion of the pore space into flowing, dendritic, and trapped fractions. A 1D simulator, previously shown to model quantitatively the effects of phase behavior in slim-tube displacements, was modified to include effects of the isolated or trapped fraction unavailable for mixing with injected fluids and the dendritic fraction, which exchanges material with the flowing fraction by mass transfer. Model formulation, numerical solution, and validation tests are described.
Results of simulations with no water present indicate that performance of a 1D CO2 flood is sensitive to deviations from complete local mixing. Calculated oil recovery decreases as the flowing fraction, Peclet number, and Damkohler number decrease. Comparisons of calculated and measured residual oil saturations (ROS's) in CO2 corefloods support this observation. Simulations of secondary and tertiary displacements by continuous CO2 injection and alternate and simultaneous injection of CO2 and water are compared. Performance of secondary displacements is not strongly affected by incomplete local mixing. In tertiary displacements, however, total oil recovery and the rate of recovery are reduced if effects of trapped and dendritic saturations are included.
Numerical Simulation of Sandstone Reservoir Models
Authors: Poston S. W. , Gross S. J. 
Published: December 2007

Summary
Sandstone reservoir rocks are not necessarily formed by random natural occurrences. These rocks are usually the result of an ordered series of depositional events that may be represented by known depositional environments. A review of the geological literature has shown that these environments are well documented by modem examples. Sand bodies found in sandstone reservoirs may be broadly divided into regressive, transgressive, serrated, and homogeneous sequences.
This paper discusses the results of a cross-sectional computer study on the depletion of an oil reservoir composed of the four basic depositional models. The studies indicate that recoveries under pressure depletion or water-drive conditions may be greatly affected by the type of sand body present in the reservoir. Geologists and engineers must be aware of the effect of depositional environment on ultimate recovery from oil reservoirs. This knowledge illustrates the usefulness of electric log and core analysis for furnishing an insight into the major flow paths in a reservoir. Additionally, the study shows how the depositional history of a reservoir may affect ultimate recovery.
An Approximate Model With Physically Interpretable Parameters for Representing Miscible Viscous Fingering
Authors: Fayers F. John 
Published: December 2007

Summary
An approximate viscous fingering model is derived with physically related parameters. Plausible assumptions are made about some limits on finger fluid mixing, and the use of a fingering function is suggested. It is shown that for the horizontal linear problem, a hyperbolic partial-differential equation governs the solvent fractional flow behavior. Satisfactory agreement with classic miscible displacement experiments is demonstrated for a reasonable choice of parameters. When gravity is introduced into the equation, the same model gives adequate agreement with the rate dependency observed in a vertical displacement experiment. Recommendations are made concerning extension of the model for use in three-dimensional (3D) compositional simulations.
Calculation of Water Influx for Bottomwater Drive Reservoirs
Authors: Allard D. R. , Chen S. M. 
Published: December 2007

Summary
This paper presents a new water influx model that differs from traditional approaches in that it includes the effect of vertical flow at the reservoir/aquifer interface. The results are presented in the form of dimensionless groups, which makes the model readily applicable to a wide range of systems. The paper concludes with a sample calculation showing how the predictions of this new model can be significantly different from those of conventional radial flow models.
Dynamic Fluid-Loss Characteristics of CO2-Foam Fracturing Fluids
Authors: Harris Phillip C. 
Published: December 2007

SummaryHigh-quality CO2-foam fracturing has recently become a very popular stimulation tool. Dynamic fluid-loss measurements were performed on a broad range of core samples to measure the effect of several parameters on CO2-foam fluid-loss coefficients. The parameters tested were core permeability, foam quality, gelling-agent concentration in the aqueous phase, and core temperature. Measurements were performed in a recirculating fluid-flow test loop.A variation of one order of magnitude in CIII for two-orders-of-magnitude change in permeability was observed from 0.02 to 10 md. For permeability below 1 md, foam quality had no effect. Fluid-loss control improved as gelling agent concentration in the liquid phase increased. CIII increased with increasing temperature as a result of temperature thinning of the aqueous phase.Passage of CO2 foams through porous media caused a significant modification in quality from the input to the effluent fluid. The ratio of liquid to gas passing through the core was measured as a function of core permeability, quality, and gelling-agent concentration. In low-permeability cores, flow proceeded as separate phases, whereas in higher-permeability cores, the foam structure remained more nearly intact.CO2 foams were found to be very similar to N2 foams with respect to the above parameters.
Cycling With Air and Other Nonhydrocarbon Gases
Authors: Striefel M. A. , Ahmed T. H. , Cady G. V. 
Published: December 2007

Summary
Injecting lean gas into condensate reservoirs is a practice currently used to increase recovery. The process reduces condensation and increases liquid recovery by revaporization. However, delaying natural gas sales for long periods of time is economically unattractive. The purpose of this paper is to investigate the effectiveness of nonhydrocarbon gases (i.e., air, N2, and CO2) for improving recovery from retrograde condensate reservoirs. A compositional model that uses the Peng-Robinson equation of state (PR-EOS) was developed to evaluate condensate reservoir performance. A 15-component hydrocarbon system and extensive experimental data were used in the study. The simulator was tuned to match the available experimental data. The model shows that nonhydrocarbon gases can vaporize hydrocarbon liquids effectively, with CO2 the most effective nonhydrocarbon for vaporizing heavy fractions.
Introduction of a Pore Geometrical Factor Defined by the Capillary Pressure Curve
Authors: Thomeer J.H.M. 
Published: December 2007

Abstract
A method is presented that provides a mathematical description of capillary pressure curves and, probably, of differences in pore geometry of samples. The technique is based on the observation that the location and shape of a capillary pressure curve reflect characteristics of the pore structure of the sample.

Introduction
It has been noted that the observed differences in shape and location of capillary pressure curves reflect some basic properties regarding the pore geometry of the samples. For example, according to basic concepts of capillarity, the following statements can be made regarding the location and shape of a capillary pressure curve.
The location of the curve with respect to the (Vb)pc and Pc axes is a measure of the interconnected pore volume and of the cross-sectional area of the pore first entered by mercury, respectively. The shape of the curve depends on the interconnection of the pores and the sorting of the pore sizes.
It has been the object of this study to use this information as a starting point in an attempt to find a unique mathematical description of the Pc - (Vb)Pc relations of different samples. It may be expected that parameters in such a relation can then be used to describe differences in pore geometry of these samples. For a practical description of the Pc - (Vb)Pc relation, however, it appears desirable to describe each curve (i.e., each sample) by a limited number of parameters so that the curves taken from all samples form a family, each member of which is uniquely determined by one single combination of values of all parameters.
A Correlation for Interference Testing With Wellbore-Storage and Skin Effects
Authors: Ogbe D. O. , Brigham W. E. 
Published: December 2007

Summary
A new correlation and set of pressure-response and pressure-derivative type curves are presented for interference test analysis. The influence of wellbore storage and skin effects at active and observation wells on interference pressure response is examined. In the case of wellbore storage and skin in one well, the correlating parameter [CDe2s]CD/rD2 is used to combine wellbore storage and skin variables in a way that makes it possible to display, on a single type curve, all interference test data that would ordinarily require a number of type curves for various combinations of CD/rD2 and CDe2s. The product of the correlating parameter is used when wellbore storage and skin effects are active at both wells. The difference in the shapes of the single-well storage type curves compared to the two-well storage case at early times can be used as a diagnostic feature in interference testing.
Three-Cone Bit Selection With Sonic Logs
Authors: Mason Kenneth L. 
Published: December 2007

Summary
Formation hardness and compressive strength correlate with calculated shear travel time, which has led to the development of a correlation between economical roller-cone bit selection and calculated shear travel time. Upper and lower shear-travel-time limits are then placed on steel-tooth and tungsten-carbide bits as a guide to help minimize the cost per foot when a well is preplanned.
Effects of Thermal and Mechanical Loading on PDC Bit Life
Authors: Glowka D. A. , Stone C. M. 
Published: December 2007

Summary
Results of numerical analyses to determine the effects of thermal and mechanical loading on the integrity of poly crystalline-diamond-compact (PDC) cutters during deep-hole drilling are presented. Cutter-temperature distributions for several drilling environments are combined with the appropriate mechanical cutting loads to predict stress distributions for the study of cutter wear mechanisms. A discussion of wear mechanisms acting on the cutting structure is presented. Suggestions based on these analyses are presented for the operation of PDC bits to increase bit life in hard, abrasive rock drilling. Microstructural design considerations for the cemented carbide that supports the diamond layer are also discussed.
Comparison of Measured and Predicted Pressure Drops in Tubing for High-Water-Cut Gas Wells
Authors: Reinicke K. M. , Remer R. J. , Hueni G. 
Published: December 2007

Summary
A considerable number of deep (&gt;3000 m [&gt; 10,000 ft]) high-volume gas wells in northern Germany show signs of increasing water production (about 800 × 10−6 m3/std m3 [135 bbl/MMscf]), This paper presents results of tests in gas wells to measure the two-phase (gas/water) pressure drop in the tubing. Experimental data are evaluated and compared with the calculations from over 15 different pressure prediction schemes. Modifications proposed for some of the methods resulted in significantly improved predictions.
Development and Testing of New Offshore Cathodic Protection Criteria
Authors: Evans Sheldon 
Published: December 2007

Summary
New sacrificial anode protection criteria developed and tested by Dubai Petroleum Co. (DPC) resulted in a 40% decrease in anode weight as compared to that required by conventionally accepted design. Derivation of the criteria is based on an analysis of extensive field results of potential surveys of seven DPC platforms that had conventional sacrificial anode protection systems. It was found that an initial platform current density of 29±2 × 10−3 A/sq ft [310±20 mA/m2] of area exposed to seawater resulted in polarization of the platform to −1 V with respect to the silver/silver-chloride reference electrode. As a consequence of this high initial polarization, the electric current requirement for protection is reduced significantly. The new criteria were used in the design of Platform JJ, which was installed in Sept. 1982. Field results that include periodic potential surveys of Platform JJ are presented and discussed.