bluuebunny/crossref_metadata_2025_split huggingface dataset:
Composition Correlations of Natural Gas in Reservoir Engineering Problems
Authors: Eckles W.W. 
Published: December 2007

Abstract
This paper is presented as a summary report of the use of well gas composition correlations obtained from mass spectrometer recordings as a means of identification and determination of reservoir continuity.
Conventional methods for detecting composition differences are expensive, elaborate, and difficult to obtain. This excludes the use of extensive composition data for most applications.
During recent years the mass spectrometer has come into general use as an analytical tool in petroleum refineries. The use of mass spectrometer composition patterns in characterizing or "finger-printing" the produced gas from a reservoir, presents a novel method for correlating gas samples from well to well. The mass spectrometer provides a trace similar to an electric log, having peaks which represent the abundance of certain hydrocarbons in the well gas sample. Without going further into the detailed analysis, the idea has been advanced that these traces or patterns could be used as a means of identifying a particular natural gas. This theory has proven to be essentially correct. The mass spectrometer pattern method is simple and cheap as compared to other standard methods. It greatly facilitates the solution of reservoir and geological problems in which correlation of well gas compositions is a factor.
Specific field applications have been made. This paper concerns the results obtained in 465 individual gas analyses from 35 fields and 77 reservoirs. In a number of cases it has been found that such data have been extremely valuable in the determination of reservoir continuity. In at least one case, the method was a valuable contribution in tracing a reservoir from sand to sand in a complex faulted field involving numerous gas reservoirs.
Field applications are presented to illustrate the possibilities of the method at the present stage of development and to stimulate the employment of this new approach by geologists and petroleum engineers in the industry.
The Effect of Heat Transfer To A Nearby Layer on Heat Efficiency
Authors: Prats Michael 
Published: December 2007

Summary
This paper provides an analytic solution in Laplace space for the heat distribution in two nearby layers undergoing heat injection at variable rates. The heat content in the layers undergoing thermal injection, divided by the cumulative net-injected heat, is known as the heat efficiency. In this treatment, the thermal properties of the layers, the thickness of the layers undergoing heat injection, and the intervening layer can have any values. The overburden and underburden are semi-infinite.
Examples are given for two sets of thermal properties and three values of the intervening layer's thickness. Only a constant rate of heat injection is considered in the examples.
Results indicate that significant thermal interaction occurs at an intervening layer thickness as great as 45 ft, with the effect being faster and more pronounced the thinner the intervening layer.
Interpretation of Water Saturation Above the Transitional Zone in Chalk Reservoirs
Authors: Larsen Jens K. , Fabricius Ida L. 
Published: December 2007

Summary
The free water level (FWL) in chalk reservoirs in the North Sea may be hard to establish owing to strong influence from capillary forces and lack of pressure equilibrium across the reservoir. Even where wireline formation tester data on the FWL are available in one well, it is no straightforward task to predict the FWL in other parts of the field, where only conventional core analysis and logging data are available. It is thus difficult to predict the geometry of the hydrocarbon-bearing interval.
This paper offers a simple model which, in a given well, allows us to predict the location of the FWL from conventional core analysis and logging data if wireline formation tester data are available from another well.
Water saturation is averaged over the internal surface of the formation by applying Kozeny's equation, resulting in a pseudo water-film thickness (PWFT). The PWFT is larger than the equilibrium water-film thickness calculated from the augmented Young-Laplace equation because it includes water associated with grain contacts. The PWFT has a gradient with true vertical depth (TVD) that is related to the capillary pressure; this gradient is approximately the same for the wells investigated. Consequently, a unique relationship between the PWFT and the height above the FWL can be established, provided that the depth of the FWL is known from formation pressure data. The unique PWFT height above the FWL relationship can be used to establish the FWL in offset wells for which no reliable formation-pressure data exist. The estimation of the FWL in offset wells is inexpensive because it requires the use of log data and sufficient conventional core-analysis data only.
The model was tested on seven wells from the Gorm and Dan field in the North Sea and resulted in predictions of the FWL in the Dan field wells based on wireline formation tests in one Gorm field well.
Diaphragm Slush Pump
Authors: True Martin E. , O&apos;Reilly W.M. 
Published: December 2007

Abstract
To provide means for improving the economics of slush pump operations, development work was initiated to perfect a pump in which the moving parts are in contact in a clean lubricating fluid. Alter years of research and laboratory and field testing, a full scale pump has been developed which incorporates means for isolating the abrasive drilling fluid from the rod, piston, liner, and rod packing. A diaphragm is employed as a membrane for separating the clean fluid reciprocated by the pistons from the drilling fluid. Automatic means are included for maintaining a constant volume of fluid in the intermediary system. The diaphragm slush pump, during an observation period of nine months in competition with a conventional rig pump in drilling service, operated satisfactorily. An appreciable cost reduction in the replacement of expendable parts, except valves, has been achieved through the use of diaphragm pump compared to a conventional pump.

Introduction
The method of circulating drilling fluid with reciprocating pumps today is basically the same as that employed in the early days of rotary drilling. A basic weakness of this equipment is that the working parts are exposed to an abrasive fluid which results in relative short life and a high operating cost. Improved design and materials of parts exposed to the abrasive fluid have contributed to prolonging the working life, but the cost per operating hour leaves much to be desired as reciprocating slush pump continue to increase in size and in horsepower to deliver fluid at the high volumes and pressures frequently employed to achieve increased rates of drilling.
Since the beginning of rotary drilling, much effort has been directed to various designs of pumps which would provide means of reducing the wear on expendable parts. Even as recently as the early 1940's, plunger-actuated diaphragm slush pumps were being manufactured and sold for rotary drilling service.
A Porous, Permeable Carbonate for Use in Oil Recovery Experiments
Authors: Meister John J. 
Published: December 2007

Introduction
Previous research in the use of surfactants and polymers Previous researchin the use of surfactants and polymers in tertiary oil recovery concentrated onsandstone reservoirs, with most laboratory work for the design using Bereasandstone and with a final check on the system being made in reservoir corematerial. With increased understanding of how surfactants act to recover oilcarbonate reservoirs are being considered for surfactant flooding. However, aporous permeable, carbonate mineral is needed to permit numerous tests ofvarious compositions in carbonate rock during the design of an oil recoverysystem for carbonate reservoirs. An appropriate core material was found aftersearching for quarried, consolidated, fine-grained, carbonate minerals with 20%or more porosity and 100 md or more intergranular permeability. Only a rockmeeting these criteria will permit reproducible laboratory tests to beconducted under representative field conditions - a frontal advance rate of upto 0.6 ft/D and a pressure gradient of less than 1 psig/ft. A rock meetingthese criteria is described here.
Porous Permeable Carbonate Porous Permeable Carbonate The most appropriatecombination of rock properties for core tests was found in a dolomite quarriedby J. E. Baker Co.* Baker dolomite quarried in Millersville, Sandusky County, OH, is a primary, sedimentary dolomite formed in a warm. shallow marineenvironment. This rock is from the Niagara group, Guelph formation, UpperSilurian epoch, Paleozic era and is considered 400 to 425 million years old.The dolomite is highly crystalline, generally massive and varies from nearlywhite to light
TABLE 1-DATA FOR BAKER DOLOMITE
Porosity, Permeability, and Grain Density Porosity, Permeability, and GrainDensity Porosity Permeability Grain Density Plug (vol%) (md) (g/cm3) Plug(vol%) (md) (g/cm3) 1 22.5 65.7 2.86 2 26.8 126.0 2.86 3 28.2 187.2 2.86 4 23.376.2 2.86
Chemical Composition
Weight Percent Element Composition Ca* Mg** Fe Mn Si Cr Upper limit 0.1 0.030.01 0.01 22.6 12.7 Lower limit 0.01 0.003 0.001 0.001
Relative Displacement Index Relative Plug Displacement Index 1 +0.414 2+0.689
JPT
P. 1632
Pore-Scale Modeling of Multiphase Flow in Fractures and Matrix/Fracture Transfer
Authors: Hughes Richard G. , Blunt Martin J. 
Published: December 2007

Summary
We use pore-scale network modeling to simulate imbibition in fractures and the matrix/fracture interaction accounting for viscous forces and flow in wetting layers. We represent the fracture as a 2D lattice of conceptual pores and throats connected to a 3D network that models the rock matrix. We find that the matrix adjacent to the fracture plays an important role in controlling matrix/ fracture transfer.
Conditioning of Lévy-Stable Fractal Reservoir Models to Seismic Data
Authors: Gunning J. , Paterson L. 
Published: December 2007

Summary
We have developed methods of conditioning nonstationary Lévy-stable geostatistical models1,2 to 3D seismic data. The technique involves adapting the sequential Lévy simulation method so that the convolutional response of the realizations acceptably matches the seismic amplitude map. A rejection scheme is used, which requires fast, repetitive simulation of gridblock columns and generation of convolutional responses. The nonstationarity of the model means that this cannot be achieved using the conventional large kriging system. We use a different, but comparably rapid method, based on storing the relevant parts of a sequential simulation calculation for the column. Working directly with the amplitude traces also has the advantage of avoiding the ambiguities and nonuniqueness involved in inverting the traces to acoustic impedance.
The most difficult part of the problem is estimation of the seismic wavelet, and this is often done nonoptimally. We describe a sophisticated method of estimating the wavelet and show that this can yield better-than-expected results. Suitable rejection criteria are proposed, based on reasonable probabilistic models. The application of the technique is demonstrated with a field example.
Life Evaluation of a 35-kV Submarine Power Cable in a Continuously Flexing Environment
Authors: Pieroni Charles A. , Fellows Bruce W. 
Published: December 2007

JPT Forum articles are limited to 1,500 words (including 250 per table or figure) or a maximum of two pages. Forum articles may present preliminary results or conclusions from continuing investigations or may impart general technical information that does not require publication as a full-length paper. Forum articles are subject to approval by an editorial committee. paper. Forum articles are subject to approval by an editorial committee. Letters to the editor are published as Dialogue and may cover technical or nontechnical topics. SPE-AIME reserves the right to edit letters for style and content.

Introduction
This paper evaluates the life of a 35-kV power cable for connecting a single-anchor leg mooring (SALM) buoy with a deepwater, offshore platform. This system is unique in that the cable flexes constantly during compression as the mooring buoy moves in the water. To predict the effects of this constant flexure while energized, a flex simulator and electrical circuit were devised to duplicate the service environment as closely as possible.

System Description
A deepwater platform is connected by power cable to a SALM buoy a few asks away. The buoy design (Fig. 1) includes an articulated leg with universal joints to which the cable is clamped. Flexing of the loop in the cable where it crosses a universal joint was our major concern. The cable must operate continuously at 34.5 kV for an expected life of 30 years.

Test Cable and Apparatus Description
A three-conductor cable nearly identical to the production cable was manufactured for the evaluation. It production cable was manufactured for the evaluation. It consisted of three No. 1/0 AWG stranded copper conductors with an extruded ethylene-propylene rubber (EPR) insulation, These conductors were cabled together and armored with 30 No. 4 BWG galvanized steel wires, each jacketed with high-density polyethylene.
The test apparatus consisted of a fixed cable support at one end and a pivoting swing-ann 18 ft (5.49 m) away powered by a hydraulic piston (Fig. 2). The swing-arm pivoted at the fixed base and was raised and lowered at the free end in a sinusoidal motion by a hydraulic piston. The test cable was clamped to the fixed support and the swing-arm, with a loop of the desired size in between.
JPT
P. 914
Multibranch Injector/Producer Wells in Thick Heavy-Crude Reservoirs
Authors: Ehlig-Economides Christine A. , Fernandez Belkis , Economides Michael J. 
Published: December 2007

Summary
With modern drilling techniques, it is now possible to drill wells with multiple branches emanating from the same vertical or even horizontal trunk. Several heavy-crude reservoirs are very thick, and low vertical permeability would make them unattractive for single horizontal wells. Further, the much higher viscosity of the reservoir fluid results in highly unfavorable mobility. Thus, drilling stacked horizontal branches would create effectively thinner drainage areas in which the vertical mobility is far more forgiving. However, the clear benefit derived from thermal recovery favors steam injection and invites investigation of ways to improve on the Steam Assisted Gravity Drive (SAGD) application.
As an extension of the SAGD concept, this paper uses thermal reservoir simulation to investigate the effects of increasing the spacing between the injector and producer, or adding producers above or below the SAGD configuration, to mine more of the heat transferred to the reservoir by the injected steam. Simulations are performed with the Eclipse 500 thermal simulator using reservoir and fluid properties typical of the Bachaquero field in Venezuela. Economics confirm the merits of the approach.
The Effect of Heat Transfer Between Nearby Layers on the Volume of the Steam Zones
Authors: Prats Michael 
Published: December 2007

Summary
The work of Mandl and Volek1 is extended analytically to include the effect on the volume of the steam zone in one layer owing to heat transfer from a second layer undergoing steam injection. The contribution of the heat transfer delays the onset of heat convection across the advancing condensation front (the critical time) and significantly increases the volume of the steam zone even where 30 or more feet separate the layers. The increase in the heat content of the steam zone (or volume) increases with increasing ratio of the sensible to latent heat of the injected steam, and is larger than the increase in the total heat content. The interpretation for this behavior is that heat transfer delays the rate of condensation of the steam vapor, this being more important at poor steam qualities. Results of the simple approach presented here have been confirmed qualitatively through numerical simulation.
Dynamically Overbalanced Coiled-Tubing Drilling on the North Slope of Alaska
Authors: Kara D. T. , Hearn D. D. , Gantt L. L. , Blount C. G. 
Published: December 2007

Summary
Coiled-tubing drilling (CTD) continues to play a dominant role in through-tubing sidetracking of wells on the North Slope of Alaska. Recently several CTD candidates were targeted in an overpressured reservoir. Three wells were successfully CT sidetracked as a pilot project in this overpressured reservoir. The ultraslimhole directional-drilling system with a 2.75-in. nominal openhole diameter developed at Prudhoe Bay1 was used in combination with an unconventional approach to maintain overbalanced conditions when sidetracking these wells.
Hydraulic modeling showed that with a kill-weight drilling fluid, the calculated equivalent circulating density (ECD) at the sand face could approach the regional fracture gradient. In addition, kill-weight mud in the formulation required for CTD operations would be a significant expense. To address these concerns, the wells were CT sidetracked using a less expensive underbalanced drillingfluid system. Although the drilling-fluid hydrostatic pressure was less than reservoir pressure, overbalanced drilling conditions were maintained dynamically by the high ECD while circulating, and controlled by increasing the surface pressure using a choke when circulating at less than drilling rates.
The Effect of Uncertainty in Wave Force Coefficients for Offshore Structures
Authors: Nolte Kenneth G. 
Published: December 2007

Abstract
A probability distribution, which incorporates the random occurrence of wave heights and the uncertainty in the force coefficients of the Morison equation, was derived for the forces on offshore structures.
The random occurrence of wave heights was assumed to be described by a Weibull distribution, and the uncertainty in the force coefficients was assumed to be represented by a normal distribution. Wave force was assumed to be proportional to wave height raised to a power.
The assumed distributions and force relationship may not describe exactly the actual problem within a general framework, but the assumptions are believed to be applicable to the range of wave heights and conditions occurring for the selection of static design criteria for the forces on offshore structures. The applicability of the assumptions is enhanced because the primary results are expressed as ratios, which require only relative accuracy and not quantitative accuracy.
Hawser System Design for Single-Point Moorings
Authors: Woehleke S.P. , Flory J.F. , Sherrard J.R. 
Published: December 2007

This paper presents design data for mooring hawsers for single-point moorings (SPM)-Properties of materials and constructions commonly used are discussed and compared. Factors that affect new and used hawser strength are discussed. Recommendations are made for SPM hawser material, construction, and safety factors for U.S. deepwater ports.

Introduction
During 1977, Exxon Research and Engineering Co. conducted a study for the U.S. Coast Guard to prepare guidelines for evaluating single-point moorings (SPM) for U.S. deepwater ports. As part of the study, SPM hawser systems were examined. This paper covers the major findings pertaining to hawsers.The hawser system serves to moor tankers to the SPM. An SPM hawser assembly consists of a large synthetic rope spliced to form eyes at both ends, or spliced end-to-end to form a loop, referred to as a strop. The eyes or ends of the strop are placed on thimbles, and chafing chains are attached to the thimbles. Flotation devices are provided to keep the chafing chains and hawsers afloat when a tanker is not moored. A typical SPM and hawser system with a moored tanker is shown in Fig. 1.Our examination of SPM hawser systems focused mainly on design. Information from many sources was gathered and analyzed in a comprehensive study of synthetic rope properties of interest in SPM hawser design. Data also was gathered for analyzing the associated hawser components, such as thimbles, flotation units, and chafing chains. Based on this study, guidelines were prepared for designing SPM hawser systems. Flory et al. presented a complete study of SPM hawser systems, along with studies on other aspects of SPM design. They included information on SPM hawser materials, constructions, breaking strengths, elasticities, safety factors, and assemblies. Supportive information presented here is not always complete. In some areas, we can give little more than conclusions and recommendations. Flory et al. give a more complete understanding of and more background to support our conclusions and recommendations.

SPM Hawser Materials
Nylon, polyester, and polypropylene synthetic fibers commonly are used for SPM hawsers. Other synthetic and natural rope fibers have properties detrimental for use in SPM'S. Fig. 2 gives comparative load-elongation curves for new nylon, polyester, and polypropylene ropes of the same construction. Table 1 shows comparative breaking strengths for large ropes made of each material.Fiber manufacturers often coat synthetic fibers to obtain desirable characteristics. Fibers of different coatings are differentiated by grade. Fibers used to manufacture rope are coated for maximum strength and to resist abrasion. Fiber manufacturers consider these fiber coatings proprietary, so it is difficult to compare the qualities of coatings used by different manufacturers. The characteristics imparted by the coating greatly influence the performance of an SPM hawser.

Nylon
Nylon is the most commonly used fiber for SPM hawsers.
JPT
P. 917
Lime Treatment of Oily Saline Drilling Wastes
Authors: Deuel Lloyd E. , Holliday George H. 
Published: December 2007

Summary
Land treatment of oily saline drilling wastes is problematic in lowpH, high-iron, and aluminum-activity soils commonly found in China, Southeast Asia, and the Americas. Problems stem from the addition of salts promoting hydrolysis of iron and aluminum acidity, exacerbating an often extreme (pH &lt; 4.0) acid reaction. Most drilling wastes are strongly alkaline and offer a beneficial neutralization reaction when mixed with native acid soils. However, land treating of oily saline drilling wastes generally is limited by either the petroleum hydrocarbon content or salinity before sufficient base is added to neutralize excess acid in the receiving native soil.
This paper offers a practical and economical means of managing potentially problematic reactions by the prophylactic treatment of oily saline drilling wastes with agricultural-grade hydrated lime (calcium hydroxide) prior to land application.
The results presented show that hydrated lime reacts with the oil-base drill cuttings/acid-soil mixture in a manner promoting the biological degradation of the oil. Lime also functions to sequester free-oil fractions, making it easier to land-apply oily wastes and to control application rates. Free lime neutralizes excess soil acidity. The high pH associated with hydrated lime is ameliorated in the lime/drilling waste/receiving soil blend by fixation of atmospheric carbon dioxide to a pH &lt; 8.3 (carbon dioxide and water naturally attain a pH of about 8.3, as shown by the decrease of reserve pit fluid pH with time). The data suggest that the optimum lime application is equivalent to the total petroleum hydrocarbon (TPH) content as measured on a dry-weight basis.