bluuebunny/crossref_metadata_2025_split huggingface dataset:
The Radial Movement of Permeability Fronts and Multiple Reaction Zones in Porous Media
Authors: Hekim Yusuf , Fogler H. Scott , McCune Conwell C. 
Published: December 2007

Abstract
Sandstone formations contain a variety of minerals including carbonates, clays, feldspars, quartz, and, in some cases, valuable compounds of uranium, vanadium, and copper. When a reactive fluid such as acid is injected into these porous rocks to dissolve the minerals, their dissolution rates are different because of differences in structure and chemical composition. Consequently, multiple reaction zones develop as a reactive fluid flows through the rock. This study, describing the movement of these reaction zones during sandstone matrix acidizing, also has application in hydrometallurgy and in-situ acid leaching of minerals.
Laboratory tests to predict the effects of acid injection usually are carried out by flowing acid through a core sample while permeability and fluid effluent concentration are monitored. If the minerals in a particular sample dissolve at approximately the same rate, a lumped parameter model satisfactorily describes the movement of a single reaction zone through the core. However, for the case of high temperatures, long cores, or long injection times, this model does not predict the effluent acid concentration correctly, and a distributed parameter model including the movement of multiple reaction zones is required. This paper describes the development of such a model and its verification by core flow experiments.
The study shows that when various minerals including quartz are being dissolved during matrix acidizing, larger acid volumes are required than predicted by previous models.
Two Decades of Electrical Logging
Authors: Doll H.G. 
Published: December 2007

The present paper, written at the request of the editor of the JOURNAL OFPETROLEUM TECHNOLOGY, gives a brief history of the various logging methods andof their progressive development during the last 20 years. More generally, itrefers to the different operations performed in drill holes at the end of anelectric cable to locate the permeable formations and to determine theircharacteristics, such as porosity, fluid content, and dip; to procure samplesof the formation by sidewall coring; and to determine data concerning the drillhole itself, as, for example, its diameter and deviation from vertical.

Electrical Logging

Correlation and Bed Thickness Determination
The first log in an oil well was made in 1927 and comprised only aresistivity curve. The sharp contrast in resistivity from one bed to anothersuggested that such a log would be very useful for correlation between wells, aconclusion that was confirmed by field experience. In 1931, the SP log wasadded. This parameter not only improved the qualities of the electric log forcorrelation purposes, but made it possible, in many cases, and particularly insoft formations, to locate permeable beds and to determine their boundarieswith reasonable accuracy. The combination log, comprising one resistivitycurve, generally a short normal, and the SP log, was introduced commercially inthe United States in 1932 and was immediately recognized as a very valuabletool.

First Attempts at Quantitative Analysis
Until about 1937, the application of electrical logging was, in many cases, limited to correlation and bed thickness determination. During that period, however, attempts were progressively made to detect oil sands by qualitativeinterpretation, especially by comparing the resistivity of a given permeablebed in different wells drilled in the same field. This resulted in valuableconclusions in many cases, and also brought to light the important influencethat mud filtrate invasion has on the apparent resistivities as measured in thedrill hole.
Around 1938 the problem of quantitative interpretation received increasedattention, when the first paper dealing with that problem was published. Fromthere on, not only the service companies, but the oil companies themselves, didextensive work to improve the interpretation. Subsequent papers discussingempirical relations between formation factor and porosity, and betweenresistivity of the uncontaminated part of a permeable bed and its oil and watersaturation, brought important and basic contributions to the problem ofquantitative analysis.
How Policies Affect Rates of Recovery From Mineral Sources
Authors: Lohrenz John , Burzlaff Bernard H. , Dougherty Elmer L. 
Published: December 2007

Abstract
Higher royalty and other production-contingent payment policies cause some otherwise economical mineral projects to become uneconomical. But, even for projects that are still economical, such payments lead to a slower rate of mineral production and may decrease ultimate recovery.
A Review of the Production Performance of Three Deep Miocene Oil Pools in the Los Angeles Basin
Authors: Doyle C.L. 
Published: December 2007

Abstract
A review is presented of the production performance of the City zone of the Inglewood city pool, Potrero field; the Wardlow pool of the Long Beach field and the Santa Fe zone of the Santa Fe Springs field. Production is from thick sections of Miocene sands with air permeabilities from 10 to 100 md. The pools have produced at near capacity rates from early in their history; oil recovery to date has been primarily from pressure depletion. Maximum gas-oil ratios were reached at recoveries of 46 to 58 per cent of the gas originally in place and 6 to 10.5 per cent of the oil originally in place. Early oil rate vs oil recovery trends indicate 13.5 to 23 per cent ultimate oil recovery. The Wardlow pool is now producing primarily by gravity segregation and considerably higher ultimate oil recovery is foreseen than was indicated front earlier performance. From a depletion standpoint, the substantial oil recovery following maximum gas-oil is largely due to permeability and mobility ratio variation within the thick section.

Introduction
This paper presents a review of the production performance of three deep oil pools in the Los Angeles basin, Calif., which produce from thick sections of Miocene sand in the low permeability range. The pools are the City zone of the Inglewood city pool, Potrero field, the Wardlow pool of the Long Beach field, and the Santa Fe zone of the Santa Fe Springs field. The location of these pools within the basin is shown in Fig. 1. In reference to the central area of the city of Los Angeles, the Inglewood city pool is 8 miles to the southwest, the Wardlow pool 18 miles to the south, and the Santa Fe Springs field 12 miles to the southeast.
This paper is in the nature of a case history of these pools with the purpose of (1)describing the accumulation, (2)reviewing the oil and gas production performance and the indicated oil recovery efficiency, and (3)comparing the behavior and recovery experience of the three accumulations.
Use of a Downhole Mud Motor as a Pump for Drillstem Testing
Authors: Cobbett James S. 
Published: December 2007

Summary
The increasing expense and complexity of exploration drilling, coupled with rapid advances in computer and microprocessor technology, have led to the development of computer-assisted wellsite logging units. This paper discusses two methods currently in use for the collection and storage of rig and mud data during drilling and tripping operations and application of these methods to improve wellsite safety and drilling efficiency.

Introduction
Mud logging units first were employed in the search for hydrocarbons in the early 1940's. In the following decade, advances in gas chromatography and electromechanical sensors enabled these same units to measure combustible gases and rate of penetration more accurately. In the latter half of the 1960's, an increase in the number of exploration wells being drilled in more dangerous offshore locations and geologically unpredictable environments, such as the North Sea, led to a growing awareness of the need to improve fig safety and to reduce spiraling drilling costs (Fig. 1). As a result of this need, the monitoring and recording of an ever-increasing number of drilling parameters has become the norm.

Development
In the interests of safety and, in particular, in an attempt to reduce the incidence of loss of life and/or property resulting from blowouts, empirical methods were developed in the mid-1960's to identify abnormal pressure regimes with some of the many drilling parameters recorded. Jorden and Shirley (with later refinement by Rehm and McClendon), for example, developed for the Gulf of Mexico the drilling or d exponent to normalize the effects of weight-on-bit (WOB), rotary speed, and bit size on drill rate and to try to make the d exponent accurately reflect changes in pore pressure. The requirement for instantaneous and accurate measurement of these parameters was extremely important. Furthermore, changes in flow-out, mud weight, and pit level remained important factors in preventing a kick from becoming a blowout. Hence the accurate measurement of the drilling and mud parameters was crucial. Drill monitoring systems included kelly height, fig heave, hook load, WOB, rotary speed and torque, and casing and standpipe pressure. Mud monitoring systems included mud weight, temperature, resistivity, and flow in and out, pump strokes, total pit volume, and trip tank volume. Gas monitoring systems included chromatographic analysis and detection of hydrocarbons, H2S gas, CO2, nitrogen, and oxygen.

Centralization of Data Recordings
One serious drawback was that readings were taken at many different locations on the fig. Mud weight was measured in the pits and on the shakers, the driller's weight indicator displayed WOB, and the geolograph recorded standpipe pressure, torque, rotary speed, and hook load. A separate instrument was used to show changes in pit level.
JPT
P. 2899^
A Study of Solubility of Strontium Sulfate
Authors: Jacques Donald F. , Bourland Brent I. 
Published: December 2007

Abstract
This paper describes the results of a solubility study of strontium sulfate in sodium chloride brine. A predictive equation for the solubility of strontium sulfate is presented, which is useful for calculating solubility in water containing 0 to 200 g/L (0 to 200 g/dm3) sodium chloride at temperatures from 100 to 300° F (38 to 149°C), with pressures from 100 to 3,000 psig (689 to 20 684 kPa), and total ionic strengths of 0 to 3.43. This paper also describes the experimental technique employed and the special equipment designed for this study.
Test Results of a Corrosion Logging Technique Using Electromagnetic Thickness and Pipe Analysis Logging Tools
Authors: Iliyan I.S. , Cotton W.J. , Brown G.A. 
Published: December 2007

Summary
Recent innovations in subsurface corrosion practices of the Arabian American Oil Co. (ARAMCO) have reduced logging and workover costs substantially and have permitted the detection of corrosion in the outer string of two concentric casing strings.
At the request of ARAMCO, Schlumberger conducted test under both simulated and field conditions. Results showed that the data required to evaluate casing corrosion in a 7-in. × 9 5/8 -in. completion can be obtained during a single logging run using a 21.6-in. coil spacing electromagnetic thickness tool (ETT-A TM) sonde (as opposed to two runs with 17.6-in. and 21.6-in. sondes previously used). In addition, corrosion of the outer string of 9 5/8-in. or 13 3/8-in. casing can be detected by using the results of the ETT-A logs and pipe-analysis tool (PAT) logs or caliper logs.
To date, the application of this technique has been very successful in ARAMCO's operations.

Introduction
For several years ARAMCO has used the ETT-A in conjunction with the multifingered caliper (MFC) tool for monitoring casing corrosion in single strings of both 7-in. and 9 5/8-in. casing. The results of these logs were often the basis for workover recommendations in injection wells and to a greater extent, when run in conjunction with workover operations on producing wells, the basis for additional operations to ensure good wellbore integrity.
In the past, two separate logging runs were made to evaluate corrosion in each of the 7-in. and 9 5/8-in. casing strings. The 17.6-in. coil spacing ETT-A sonde was used in 7-in. casing while the 21.6-in. coil spacing ETT-A sonde was employed in 9 5/8-in. casing. The obvious disadvantage of this technique is the additional cost incurred in making two separate logging runs. An additional disadvantage is the added workover rig downtime.
As corrosion in the near-surface outer string of dual casing strings increased, it became imperative to develop a technique by which corrosion in the outer string could be detected and corrected before complete breakdown of the casing resulted in underground communication or surface leaks.
To this end ARAMCO approached Schlumberger to determine whether any of the corrosion monitoring tools (specifically the ETT-A) then in use could be adapted to detect corrosion in the outer string of two strings of pipe and to determine whether an optimal coil spacing existed that could be used in both 7-in. and 9 5/8-in. casing strings.
Tests were undertaken by Schlumberger in their AlKhobar. Saudi Arabia, shops to determine the optimal coil spacing of the ETT-A and to confirm that this spacing could respond to the total metal of dual casing strings. Once this optimal spacing was determined, it would then be possible to use the ETT-A to check the total metal present, and when run in conjunction with the PAT or MFC, it would be possible to differentiate the corrosion affecting the inner and outer strings.
JPT
P. 801^
Effects of Vaporization and Temperature in Gas/Liquid Relative Permeability Experiments
Authors: Counsil John R. , Ramey Henry J. 
Published: December 2007

Abstract
Liquid vaporization can influence the results of unsteady, external gas-drive relative permeability experiments. At elevated temperatures, liquid vaporization may affect (1) displacing gas mixture volume, (2) displacing gas mixture viscosity, and (3) volumetric liquid saturation calculated from a material balance. Approximate methods are presented to correct laboratory displacement data for the effect of liquid vaporization on displacing gas mixture volume and viscosity. An approximate method also is presented to evaluate the magnitude of liquid saturation reduction caused by liquid vaporization. By use of a modified Jones and Roszelle1 calculation procedure, equations are developed to describe the dynamic displacement of liquid water by nitrogen gas at elevated temperatures. A conventional analysis of three displacement experiments demonstrated the apparent temperature dependence of gas relative permeability. Use of the proposed method indicated that corrected gas and water relative permeability curves are not strongly temperature dependent for the artificially consolidated sandstone cores used in this study.
Design and Development of Electric and Hydraulic Cables for Subsea Wellhead Control in the North Sea
Authors: Everett John W. , Jones Idwal L. , Hill David J. 
Published: December 2007

Summary
This paper presents a development program, from design formulation to field test, for North Sea wellhead-control cables. Typical design considerations, desired performance data, and actual test results are included for both electric and hydraulic cables. Jointing, terminating, and installation techniques also are discussed.

Introduction
Subsea wellheads operating remotely from a tower or manifold center require electric and hydraulic power and control lines. These systems, some for North Sea installation from 1980 onward, require specially developed cables and terminations.
These cables must maintain a stipulated performance and withstand handling and installation performance and withstand handling and installation operations. They must withstand seabed conditions and, in the unfortunate event of damage by trawler or anchor, be capable of recovery and repair.
Cables against one of several contracts have been manufactured and installed in the North Sea during 1980. This paper discusses the general cable design requirements specified and the prototype development program. The values and design parameters given are not specific to any particular system and should be considered as purely typical results from a wide-ranging program.

Typical Cable Specification Requirements
Typical design and performance data, for both hydraulic and electric cables, are given in Tables 1 and 2 (Figs. 1 and 2).
Various hose liners for the hydraulic cables may be specific for compatability with methanol, glycol, synthetic hydraulic fluids, and mineral oils. Cold flexibility and flammability tests also are called for in some specifications.

Cable Environmental and Installation Requirements
The following list summarizes some of the typical requirements.System operational life of up to 25 years.Both minimum and maximum breaking strains for the cables, about 20 and 40 tons (18 and 36 Mg), to give adequate strength but avoid damage to subsea structures if the cable is dragged.Adequate cable modulus for the water depth of installation, typically about 4 naut. miles (7.4 km).Torque-balanced cable due to J-tube and wellhead cable installation.System life resistance to corrosion and abrasion, and adequate weight in water to give stability.The significant but variable trawl and anchor fault hazard to cables in the North Sea calls for monitoring ship control. Suitably maneuverable cable ploughs now exist.

Cable Design and Development Background
The development team was able to draw on many years of worldwide company experience in the design, development, testing, and installation of underwater electromechanical cables.
JPT
P. 413
Pulse Decay Permeability: Analytical Solution and Experimental Test
Authors: Bourbie Thierry , Walls Joel 
Published: December 2007

Abstract
A new analytical solution is presented for the laboratory pulse decay permeability problem. With this solution, permeability of a core sample can be calculated from the decay rate of a pressure pulse applied to one end of the sample. This development permits rapid, accurate measurement of permeability in samples such as tight gas sands, limestones, and shales.
A Continuous Multistage Fracturing Technique
Authors: Webster K.R. , Goins W.C. , Berry S.C. 
Published: December 2007

Abstract
Wells with multiple producing zones can be fractured one zone at a time during continuous pumping with a high degree of probability of treating all zones by [1] perforating with charges designed to produce round, burr-free holes; [21 perforating the same low number of holes [usually eight] into each zone; [3] perforating in acid; and [4] using sealer balls between frac stages exactly matching in number the holes in each zone.
During field trials of the process, recovered fluid-cut sealer balls indicated that quite often jet perforated holes had poor roundness and ragged burrs preventing good seal. It was necessary to have jet charges and guns redesigned to provide consistently round and burr-free entrance holes. Perforating the same number of holes per zone eliminates the guesswork when determining the number of ball sealers to use per stage. Experience has shown that perforating in acid reduces breakdown pressures, allowing the process to be used in areas where previous fracing indicated the method could not be applied. Using sufficient holes per zone to handle the total pumping rate at a low differential pressure prevents breaking down more than one zone at a time. High differential pressure from too few holes consumes energy and adds to the cost of the treatment. A calculation procedure is used to determine the holes required per zone based on flow rates and total cross sectional area of the perforations.
Radioactive frac sand and gamma ray tracer surveys have been used in conjunction with straddle packers to determine the zones treated. Success ratios calculated as the number of zones fractured divided by the number of fractures attempted have been found quite high in 7–8 zone wells and still greater in wells with fewer zones.
The method is less expensive than treating one zone at a time using isolating packers and is much surer of producing multiple fractures than simultaneously fracing generously perforated multiple zones. Continuous multistage fracturing produces maximum fracture area for a given injection rate as compared with simultaneous injection into multiple zones. The multistage technique also allows use of all the steps considered essential to good, single-stage treating.
Results of field trials have consistently indicated vertical fractures. The fracture orientation has been evidenced by low treating pressure gradients and by gamma ray tracer surveys.
Field work with radioactive propping agents provided a means of checking the quality of the cement job after fracturing.
Characterization of Surfactants Using a Scaling Law Interpretation of Coreflood Residual Oil Saturation Profiles
Authors: Davis L. A. , Tyler T. N. , Brost D. F. , Haskin H. K. 
Published: December 2007

Abstract
The characterization of surfactant candidates for a given reservoir can be improved by the use of linear coreflood residual-oil-saturation profiles measured along the core after chemical flooding. A surfactant formulation's functional relation of oil recovery to slug size can be calculated from a single coreflood with the assumption of a relaxed scaling law.
A volumetric linear scaling approach is developed from laboratory coreflood data. Residual-oil-saturation profiles measured in reservoir material with a microwave absorption instrument support this approximate scaling relation. Analysis of 32 linear surfactant-slug corefloods is presented as additional verification. The limits of this scaling law are defined, with emphasis on the role of mixing and dispersion.
The procedure for using saturation profiles to calculate oil recovery as a function of slug size is developed and a test case is presented. A recovery relation derived from a single coreflood saturation profile is compared with that determined by multiple conventional corefloods.
Geological Heterogeneities Important to Future Enhanced Recovery in Carbonate Reservoirs of Upper Ordovician Red River Formation at Cabin Creek Field, Montana
Authors: Ruzyla Kenneth , Friedman Gerald M. 
Published: December 2007

Abstract
Several different pore systems are present in dolomite reservoir rocks of the Red River formation (Upper Ordovician) at Cabin Creek field, MT. Each system is associated with particular depositional environments and diagenetic regimes. Pore geometry is mostly a function of the size and shape of the dolomite crystals composing the rock matrix. Mean pore-throat size, a statistical measure of pore geometry, increases as porosity percent increases, depending on the type of dolomite. This relationship permits prediction of reservoir pore geometry and a better assessment of recovery efficiency once lithofacies distribution, porosity origin, and diagenetic history have been determined for the reservoir by study of cores and rock thin-sections.