bluuebunny/crossref_metadata_2025_split huggingface dataset:
Performance of Crosslinked Hydrochloric Acid in the Rocky Mountain Region
Authors: Pabley Avtar S. , Ewing Bob C. , Callaway Ralph E. 
Published: December 2007

ABSTRACT
The crosslinked high strength hydrochloric acid system1 has led to significant production increases in Rocky Mountain wells. A total of sixty five wells have been stimulated with this system utilizing a total of over 470,000 gallons of crosslinked hydrochloric acid in concentrations ranging from 3% to 28%. Old producers as well as the newly drilled wells completed in the various formations such as, Dakota, Mission Canyon, Phosphoria, Minnelusa, Green River, Uintah, Nesson Midale, Red River etc. were treated. The bottom hole temperatures of these wells ranged between 110°F and 260°F (43°C to 126.7°C). The cumulative oil production from the sixty five wells prior to the crosslinked acid jobs has totaled to over 2,300 BOPD. After the crosslinked acid jobs the cumulative oil production has increased to over 8,400 BOPD, which is more than three fold increase in oil production. In a few individual wells oil production has increased by as low as 1–5 BOPD, whereas in some individual wells the production has increased by as high as 1,300 BOPD. One of the old oil producers in the Green River Formation, Utah, was producing 40 BOPD but after a treatment, the production increased to 200 BOPD and a sustained oil production after 90 days was 150 BOPD. Similarly, Production has increased from 16 BOPD to 216 BOPD in one of the new completions in the Dakota Formation in Wyoming.
The treatments have been successful in old and new oil wells as well as in a water injection well. Wells have been successfully treated using sand as proppant, and carbon dioxide or nitrogen in the system. The crosslinked acid system has shown success in wells where conventional acid treatments have provided marginal success or failed. Several case histories of the crosslinked acid system have been presented in recent presentations.2
Introduction to Plunger Lift: Applications, Advantages and Limitations
Authors: Beauregard E. , Ferguson Paul L. 
Published: December 2007

ABSTRACT
This paper discusses the principle of plunger lift and its possible applications.
Typical applications are: Removal of Liquids from Gas WellsHi-Ratio Oil Well ProductionParaffin and Hydrate ControlIncreased Efficiency of Intermittent Gas Lift Wells
Some advantages of this system are low initial cost, very little maintenance and that there is no external source of energy required in most cases. Limitations such as mechanical conditions, gas and liquid volumes and depths are also discussed. There will be a brief section concerning the various types of equipment available.
Calculation and Significance of Water Saturations in Low Porosity Shaly Gas Sands
Authors: Rosepiler M. J. 
Published: December 2007

Abstract
The identification of pay in low porosity shaly gas sands is made difficult by the inaccuracy of calculating and interpreting water saturations. Outlined below are techniques that have been used to calculate water saturations in this type of reservoir.
Laboratory tests have been performed to measure saturation exponent and to define the formation factor-porosity and cation exchange capacity-clay relationships. The tests indicate that saturation exponent, n, is 1.36, and that formation factor, F, is given by .9/øe2.17. Formation factor tests and empirical calculations imply that m may be a function of porosity in porosities less than five percent.
The cation exchange capacity of the rock is due to illite. As the illite contains radioactive potassium, gamma ray activity can be used to calculate cation exchange capacity. Laboratory spectral gamma ray analysis indicates that the potassium component is a good indicator of cation exchange capacity.
Water saturations are calculated using the Waxman-Smits technique. Errors induced by not accounting for clay conductivities are presented as functions of porosity, water saturation, and illite content. The induced errors are greatest in low porosity zones.
Error analysis indicates that the major source of error in calculating water saturations (excluding the effects of exchangeable cations) is the inaccuracy of determining porosity. At porosities less than five percent, the possible error in water saturations approaches one hundred percent.
Data are presented relating the error in water saturations to errors in porosity and resistivity.
The significance of water saturations in low porosity, low permeability sandstones is unclear. Drainage relative permeability data predict that except at extremely high water saturations the flowing phase should be predominantly gas.
The Effect of Weight Material Type on Rate of Penetration Using Dispersed and Non-Dispersed Water-Base Muds
Authors: Blattel Steve R. , Rupert J. Paul 
Published: December 2007

ABSTRACT
The penetration rates of dispersed and non-dispersed water-base muds were studied using Mancos Shale. The full-scale wellbore simulator at Drilling Research Laboratory was utilized. Previous studies1 have indicated that in invert oil muds higher penetration rates can be achieved when the weighting agent is ilmenite rather than barite. This study compares barite and ilmenite in water-base systems. Two grind sizes of ilmenite (fine and standard) were used in order to determine the effects of particle size on penetration rate.
In addition to these tests, hematite, fine-grind ilmenite and barite were tested in a low colloid invert oil mud system as a supplement to the original study. An additional test was conducted with a conventional diamond bit and the low colloid oil mud for comparison.
Highest penetration rates were observed with the standard particle size distribution ilmenite for the water-base muds. For the invert oil mud, similar penetration rates were observed for the fine-grind ilmenite and the hematite; the barite weighted mud resulted in relatively lower rates of penetration. The fine grind ilmenite/low colloid oil mud/diamond bit combination provided penetration rates equal to or greater than the barite/low colloid oil mud/roller cone bit combination.
The Influence Of Project Profitability On Company Growth
Authors: Brons F. , Silbergh M. 
Published: December 2007

The financial structure of a large company is quite complex. We are able, however, to follow the trend of such elements as the annual net cash income I (which is the income after paying all costs, including overhead and taxes), the annual net profit P (which is the annual net cash income minus writeoffs) and the dividend paid out. Other characteristics of a company, such as the average annual earning power i and the market value V, are not readily detectable but are related in some manner to the aforementioned elements.
In an attempt to establish mathematical relationships between the various elements a simple model of a company (Figure 1) was studied. This model starts with an investment of $1000 in a project which yields $400 annually for three years. (It is assumed in the model that the incomes are received at the end of each year.) From the definition of earning power, present value income discounted at earning power i equals investment, or Di (1200) 1000, the deferment factor Di is found to be 0.83. Using deferment factor tables, the value of the earning power i of this project is found to be 10 percent. All incomes derived from the first investment are reinvested in projects with the same characteristics as the first (i = 10 percent, three year constant income). The annual cash income first shows an irregular trend but, as shown in the top curve of Figure 2, after some time this trend stabilizes and the growth rate of I becomes constant. For complete reinvestment of cash incomes the following important relation is true:growth rate g earning power i. (1) If, however, as shown in the lower curve of Figure 2, seven percent of I is paid then the reinvestment ratio b is 0.93 and, although the cash income after stabilization obtains a constant growth rate g, this rate is less than the earning power i.
Foam Gravel Packing
Authors: Elson T. D. , Anderson G. W. 
Published: December 2007

ABSTRACT
Foam gravel packing experiments run in a full-scale model wellbore demonstrated that foam is a viable alternative to conventional carrier fluids such as water and viscous polymer solutions in select instances. Because of its special characteristics, foam may have advantages over these fluids in completions where low pressure or sensitive formations are encountered.
Results from experiments were used to design and implement gravel pack completions in nine shallow, low pressure wells in California. Other wells in the area had a history of lost circulation and washouts during drilling and completion operations using conventional fluids. The foam gravel packs suffered no loss of circulation during placement and proved to be less costly than the conventional slurry packs used in the past.
Numerical Simulation of a Production-Well-Ceritered Five-Spot in a Large Scale Micellar/Polymer Project
Authors: Roszelle Wayne O. 
Published: December 2007

ABSTRACT
The numerical SURfactant Flooding Simulator (SURFS) can be used to predict micellar/polymer field test results. In order to develop a set of data inputs, the simulator was used to match the oil and surfactant production histories of a specific well in Marathon Oil Company's 219-R micellar/polymer project and the post-flood oil saturation distributions in the vicinity of the well. The study area was the producer-centered 5-spot surrounding a single producing well and the north half of the 5-spot to the south of this well. This area was chosen for the study because this 5-spot had an oil recovery history, reservoir parameters, and operating history comparable to the total project average. Reservoir properties for the area were taken from the best available sources and well injection and production rates closely simulated actual field rates.
The final simulator run produced a very good match of oil and surfactant production from the well in both cumulative production and production rate as a function of time. Post flood saturation data from seven core tests taken in the vicinity of the well were also closely matched by SURFS.
The paper includes a discussion of the input parameters to the simulator including residual oil saturation as a function of concentration of sulfonate, relative permeability of oil and water in the presence of surfactants and sulfonate absorption.
A brief description of the mathematics of SURFS is reported elsewhere.1
Analysis of Production Tests of Hydraulically Fractured Wells in a Tight Solution Gas-Drive Reservoir
Authors: Verbeek Christiaan M. J. 
Published: December 2007

ABSTRACT
A simulation study has been carried out to investigate how accurate existing techniques are to evaluate tests of non-ideal hydraulically fractured wells in tight solution gas drive reservoirs. Especially in case fracture height is less than layer height the use of existing analytical methods can lead to erroneous interpretation of formation and fracture characteristics. Moreover a second radial flow period preceding the. real formation radial flow, can occur. Formation radial flow starts at a constant dimensionless time, independent of the height ratio, whereas formation linear flow ends at a time linearly related to fracture height. In the reservoir under investigation some frac-jobs have been carried out in stages. Wells, deviating up to 45 degrees, can intersect several parallel vertical fractures. In that case a correct analysis of tests is almost impossible. In practice conclusive results can only be obtained if a prefrac test is available or when a postfrac test formation radial flow is evidently reached.
Existing superposition methods were tested for constant pressure, constant rate and multirate cases to compare their applicabilities. In case radial flow superposition is applied in the time scale and if linear flow is significant results of multirate cases can show too optimistic kh values.
Published pseudopressure techniques to find formation kh values for solution gas drive reservoirs are improved by using average fluid properties instead of those at wellbore conditions. To accurately define fracture and formation characteristics a pseudo time factor was needed to correct for drastic changes in viscosity and total compressibility.
Conditions for the Development of Smaller Discoveries in the North Sea
Authors: Bayly C. H. , Cox T. F. 
Published: December 2007

ABSTRACT
Development options for North Sea fields are discussed and a reference scheme for marginal fields is costed. Against this reference, feasible cost reductions are discussed by broad cost categories with the aim of identifying key areas for cost control and technological innovation.
The impact of the current tax system on smaller fields is reviewed and possible changes to provide incentives for marginal fields are developed.
Sizing Separators for CO2 Flood Operations
Authors: Roye J. E. 
Published: December 2007

ABSTRACT
The design of field separation equipment under CO2 flood operations requires that many variables be addressed. During a CO2 flood, separators will be required to effectively separate large volumes of multi-component gas streams from produced oil and water. Many design assumptions which served well in non CO2 hydrocarbon service cannot be successfully applied to the design of field separation equipment in CO2 flood operations. To adequately size separators for CO2 service, specific attention must be given to design parameters such as K factors, gas density, liquid density, retention time for gas-liquid separation, CO2 and produced gas rates, and the type of vessel best suited for CO2 flood conditions.
After a detailed study of the parameters involved in the design of field separation equipment for CO2 floods, several conclusions were reached. Conventional sizing charts are not applicable in CO2 operations.One to two minute retention time is not sufficient for gas-liquid separation in CO2 operations.K factors normally used for sizing separators should be derated for CO2 operations.Horizontal separators are better suited for CO2 flood operations than spherical or vertical separators.Computer sizing of separators is necessary to determine the optimum operating settings.
New Low-Speed High-Torque Motor Experience in Europe
Authors: Beswick Andrew John , Forrest John 
Published: December 2007

ABSTRACT
A new generation of multi-lobe positive displacement mud motors designed in the USSR has been used in Europe since early 1981. A comprehensive range of experience has already demonstrated the importance and potential of this development for a wide variety of drilling applications. This paper describes the design concept of the motor which operates on the Moineau principle and discusses the performance with reference to a number of recent applications including straight hole drilling, directional drilling and coring. The slow-speed, high-torque characteristics, which permit sustained high bit weights, give near rotary conditions at the bit for the first time with a downhole motor, offering many advantages in drilling.
The references to case histories include a summary of the comprehensive use of the motors for directional drilling in two 7000 ft deep wells in granite for a hot dry rock geothermal energy research project in Cornwall, UK. In addition comments on the use of the motors with polycrystalline diamond and tricone bits for straight hole drilling are presented, together with a number of references to coring applications.
The results so far demonstrate that longer runs, faster drilling, and more successful coring are possible and that the power-speed characteristics offer new important operational options including bottom hole configurations with drilling assemblies below the motor. The walk tendency of the motors in directional drilling is opposite to that of turbines and, therefore, complements turbines for long progressive corrections in drilling tangent sections.
The technical improvements to the original design based on early operational experience are outlined and future potential applications discussed.
A New Generation Directional Survey System Using Continuous Gyrocompassing Techniques
Authors: Scott Anthony C. , Wright John W. 
Published: December 2007

ABSTRACT
This paper describes a radically new wellbore survey system based upon the principle of rate gyrocompass i rig. While the basic concept has been applied for many years in such applications as the initial alignment of inertial platform navigators, it is only recently that repetitive rate gyrocom-passing has been developed in its own right as a means to obtain directional survey data.
The benefits of this approach are that an extremely rugged and reliable sensor can be built into a 1–3/4" o.d. pressure housing as opposed to the 3–5/8" to 10-5/8" pressure housings necessary to contain currently available inertial platform designs. This is of great importance in regards to the versatility of the system to handle all directional survey requirements from orientation to surveys in production tubing.
In addition, the time to acquire a survey will in many cases be significantly reduced by virtue of the high traverse speeds possible and freedom from time dependent gyro drift sampling necessary with directional gyros. Field results to date indicate that positional accuracy is also consistently improved by elimination of systematic errors due to initial gyro alignment, gyro drift and accelerometer bias.
A New Generation 18¾-in.—15,000-psi Subsea Wellhead System
Authors: Baugh Benton F. , Gordon Colin R. , Weiland Glen C. 
Published: December 2007

ABSTRACT
A new generation 18-3/4" 15,000 p.s.i. subsea wellhead system has been specifically designed for deep-water high-pressure use. It features: (1) a breech-block profiled housing to receive a matching seat when only 3 strings are required or a 16" casing hanger for a fourth string, (2) a new seal assembly with 3 metal-to -metal seals in series plus resilient backup, and (3) a single-trip running tool and method which sets the metal-to-metal and resilient seals at a pressure higher than the well pressure to be encountered.
Design criteria were established from "scratch" to focus on actual wellhead requirements unbiased by conventional designs. Breech insert tests, based in many years' previous successful experience with breech-block connectors, involved both scale and full-size prototypes. Major development work on the new metal-to-metal seals involved models, finite-element analysis, and extensive testing.
Infill Drilling for Shale Gas Development: A Field Case Study
Authors: Horton Andrea I. , Mercer James C. , Sawyer Walter K. 
Published: December 2007

ABSTRACT
The U.S. Department of Energy has conducted a reservoir simulation study of a producing Devonian shale reservoir in Meigs Co., Ohio, following an extensive field testing program1 to determine the parameters controlling production from this unconventional gas resource. The purpose of the study was to determine the possible impact of infill drilling in established areas of Eastern gas shales production. A dual porosity reservoir simulator that was developed especially for shale gas formations was used in the study.
The simulation study applied the results of the previous field test program to history match the production from shale gas wells located near the test site in Meigs County, Ohio. A series of 70-year simulations showed that by infill drilling now, 35 years after the completion of the discovery well, cumulative production can be increased by 30 percent or more. Had the closer well spacing been implemented at the earliest possible time, cumulative production over the 70-year period could have been increased by 60 percent or more.
The Prospect And The Significance Of Western Europe's Increased Reliance On Natural Gas
Authors: D&apos;Andrea Lucio 
Published: December 2007

Introduction
The purpose of this paper is to review natural gas market developments in Western Europe by briefly examining the history of the region's natural gas market, prospects for indigenous future natural gas production, access to internal and external sources of natural gas, and demand and pricing policies for natural gas. policies for natural gas. Europe's outlook for using natural gas to meet its energy needs changed markedly with the 1972–1973 oil crisis. Before the crisis, natural gas use in Europe had been increasing with the discovery of the Groningen reserves in the Netherlands and those in the North Sea. The relatively low cost and the security of the supply provided sufficient incentives to market the gas for use in the region and to make it available for export within the region. Natural gas was an ideal fuel to replace manufactured gas. After the crisis, Europe recognized the danger of depending on imported oil and looked to other sources of energy to reduce its dependence. In light of the delays and difficulties associated with the development of nuclear energy and the use of coal, natural gas was considered to be a reasonable alternative.
European gas consumption increased rapidly in the 1970s. Although this growth has stabilized in recent years because of the region's ailing economy and the increased price of gas relative to oil, Europe is expected to continue to rely on natural gas for the foreseeable future.
A Wellbore Inertial Navigation System
Authors: Kelsey J. B. 
Published: December 2007

Abstract
A prototype wireline tool which includes a downhole inertial platform and a surface computer to spatially map a well is described. The hardware consists of a single-gimballed inertial platform with accelerometers and gyros to obtain three-axis motion information. The gyroscope and accelerometer outputs are transmitted to a computer at the surface which calculates probe attitude relative to north, east, and vertical. Double integration of the accelerometer data provides the position information. A conventional 7-conductor wireline is used for the system data transmission.
System accuracy is enhanced by advances made in the computer software which processes the data received from the tool. The software uses statistical sampling estimation to obtain optimal estimates of the system errors. Measurement errors are determined by periodically stopping the tool during the logging procedure and observing the indicated velocity measurements. This procedure, known as Kalman filtering, results in increased accuracy of the data. Present mapping systems have an X-Y-Z location accuracy of 100 to 200 feet for a typical well depth of 10,000 feet. Test results show that the new system is accurate to about 1 foot per 1000 feet of well depth. Unlike conventional systems, the inertial navigator does not require any sort of projection of the cable length (which may not be accurately known). Also, this system provides continuous data throughout the wellbore and logging speeds on the order of 10 ft/sec appear possible.
The hardware and software associated with this mapping system are described and the recent field test results are reported.