bluuebunny/crossref_metadata_2025_split huggingface dataset:
An Analysis of Post-Stimulation Production Response in the Madison: Elk Area, ND
Authors: Cramer D. D. 
Published: December 2007

ABSTRACT
Madison carbonates in the Williston Basin vary-widely in productive capacity. Often, wells achieving low oil production rates after acid stimulation respond favorably to a proppant fracturing treatment. This has occurred most frequently in fractured reservoirs with limited matrix permeability (less than 0.1 md).
The study area- consists of nine contiguous fields 10-15 miles south of the town of Williston, North Dakota. Madison reservoir development was initiated in 1980 and has proceeded steadily. A variety of stimulation techniques have been, implemented with proppant fracturing emerging as a frequently used method. This paper reviews and evaluates area reservoir characteristics and completion and stimulation practices. Also included is an analysis of the reservoir behavior during proppant fracturing treatments and of the ensuing production response. In most cases, proppant fracturing techniques have provided better productivity increases than large-scale acidizing and lower than normal decline rates.
Sand Arching - A Case Study
Authors: Risnes Rasmus , Bratli Rolf K. , Horsrud Per 
Published: December 2007

ABSTRACT
The theory for stability and failure of sand arches and cylindrical holes has been applied to actual well test data. The formation tested was a poorly consolidated oil bearing sand. The well was perforated in the actual interval, but no special sand control equipment was installed. The test procedure consisted in measuring simultaneously sand and oil production as the choke size was stepwise increased. In this way the maximum sandfree production rate was established.
Analysing the data, it can be concluded that the theory for arch and hole stability is capable of describing consistently the observed results.
Explosionproof Electric Unit Heating Systems for Offshore Rigs
Authors: Epstein F. S. , Arekapudi A. K. 
Published: December 2007

ABSTRACT
We have developed an explosionproof electric unit heater system to operate in ambient temperatures down to -30° F. (-34° C.) [-70° F. (-57° C.) with modification]. The self-contained system includes a blower, heating elements, controls and provisions for focusing the warm airstream on personnel up to 20 feet (6.1 meters) away. Ratings up to 91 KW (310,000 BTU/HR) will provide air temperature rises as high as 164° F. (91° C.).
Explosive Cutting of Stuck Drillpipe and Bottomhole Assemblies
Authors: Nimmo P. , Kamp A. W. , Leiper F. J. 
Published: December 2007

Abstract
Conventional back-off equipment has been used for many years to disconnect fran a stuck drill-string. The success rate in backing-off drill collars has been low, decreasing markedly with depth and deviation. This has often resulted in abandoning most of the expensive BHA components. This paper introduces a new explosive technique which allows cutting or back-off directly above the stuck point within the BHA components if necessary. Field evidence is also presented showing that- this technique provides a higher chance of success than conventional explosive methods, which have tended to rely on backing out a connection rather than cutting within the assembly.
The Wellsite Use of Luminescence Fingerprinting to Differentiate Oil-Base Drilling Fluid and Native Hydrocarbons
Authors: Summers C. F. , Geraghty S. , Holliday G. C. , Bell R. E. B. 
Published: December 2007

ABSTRACT
The development of a procedure, based on the application of synchronous luminescence spectrometry to the problem of differentiating crude oil and oil base drilling mud, is described. Its performance is illustrated by reference to field data from serveral North Sea wells. This 'fingerprinting' tool effectively simplifies interpretation of formation samples which are otherwise confused by the presence of oil mud filtrate.
PDM vs. Turbodrill: A Drilling Comparison
Authors: DeLucia F. V. , Herbert R. P. 
Published: December 2007

ABSTRACT
This study was undertaken to investigate and compare the two most prevalent down-hole motor types, Positive-Displacement and Turbodrill. The intent of this comparison was to evaluate the technical and operational performance characteristics and present them in a manner to aid the drilling contractor or drilling engineer in determining the best down-hole motor for a specific drilling application. Each type of drilling tool utilizing either power source possesses unique characteristics which can be tailored to the overall system to optimize the target objective; increase ROP at less cost.
Cementing Temperatures for Deep-Well Production Liners
Authors: Wooley G. R. , Giussani A. P. , Galate J. W. , Wedelich H. F. 
Published: December 2007

ABSTRACT
Temperature of cement is an important factor in properly cementing deep well production liners, yet current methods of determining cement temperatures do not account for all variables. In this paper a computer model predicts temperatures of cement while pumping and while waiting on cement, compares computed and measured temperatures, defines the importance of certain cementing variables on temperatures, and provides an explanation of difficulties encountered while cementing liner tops.
Long-Term Control of Paraffin Deposition.
Authors: Woo G. T. , Garbis S. J. , Gray T. C. 
Published: December 2007

ABSTRACT
Paraffin-related problems occur in almost all oil producing areas throughout the world. These problems can be encountered in any part of the production system from the time the crude leaves the reservoir until it reaches the refinery. As a result, operators spend a large amount of time and money to correct paraffin-related problems.
Traditionally, operators have been forced to remove paraffin deposits from downhole equipment, tubular goods and surface equipment using mechanical, thermal or chemical methods. In many cases, a combination of two or more methods are employed. The major disadvantage of these methods is that they treat paraffin-related problems after they have occured.
The treatment of wells with dispersants and paraffin deposition inhibitors generally reduces or slows paraffin build-up. However, this inhibition is often very short-lived, because the well production quickly carries the chemicals to the surface. The addition of a long-term solid paraffin deposition inhibitor with the proppant during a hydraulic fracturing treatment has proven to extend this inhibition time. The solid paraffin inhibitor slowly releases the paraffin inhibitor chemical throughout the early production of a well.
This paper will describe a laboratory simulation of paraffin deposition used to evaluate two paraffin inhibitors in nine etudes. The two paraffin inhibitors evaluated were: (1) a blend of crystal modifiers in a controlled-release matrix form and (2) a commiercially available ethylene-vinyl acetate copolymer solid. One field evaluation presented compares the long-term effectiveness of both paraffin inhibitors. In a second field evaluation, the blend of crystal modifiers was used in two wells to successfully control paraffin deposition. In both field evaluations, the blend of crystal modifiers in a controlled-release matrix form has successfully prevented paraffin deposition.
Numerical Computation of Temperature Distribution in a Wellbore While Drilling
Authors: Corre B. , Eymard R. , Guenot A. 
Published: December 2007

ABSTRACT
There is a need for determining temperature profiles in and around a wellbore during drilling phases. A computer model has been developed.
To take into account an evolutive geometry at the level of the tool, an adaptive grid refinement was used; it ensures a better physical representation. The unknowns are the temperatures at the center of each grid block and of each interface. The non-linear equations are discretised in finite-difference fully implicit scheme and solved by the Newton's method.
Complex rheological models are used to improve fluid mechanics' representation. At any location and time, the flow nature is determined and then pressure losses and connective heat transfer coefficients are calculated. Energy source terms are function of location and time.
Any flow history and drilling sequence may be simulated. Typical drilling sequences are presented. This model has been used in order to design mud and drilling programs to ensure a better hole stability.
A Simplified Predictive Model for CO2 Miscible Flooding
Authors: Paul G. W. , Lake L. W. , Gould T. L. 
Published: December 2007

ABSTRACT
The purpose of this paper is to present a rapid, inexpensive, and reliable method for the economic evaluation of CO2 miscible flooding. The method consists of a reservoir model for the prediction of oil, water, and CO2 rates, combined with an economic model for the calculation of discounted cash flow and other profitability indices. The model is validated against field floods, laboratory data, and numerical simulation. Model predictions of the sensitivity of profitability to some reservoir properties and operating variables are presented.
Subsea Hydraulic Power Generation and Distribution for Subsea Control Systems
Authors: Pipe Tony 
Published: December 2007

ABSTRACT
This paper is designed to outline the hydraulic aspects of subsea control system. To familiarize the reader, various system configurations and their particular applications are discussed. A detailed discussion on the major features of a hydraulic control system is then followed by a description of a typical manifold system and actual characteristics of an existing system.
The paper outlines important aspects such as hydraulic fluid selection and maintenance, specifications for hydraulic power units and subsea control lines, selection of valve actuators and the interfacing of equipment both at the design and installation phases.
Diverting and Controlling Offshore Subsea Blowouts
Authors: Hammett D. S. 
Published: December 2007

Abstract
This paper presents a concept for diverting and controlling a subsea blowout to prevent major pollution in shallow or deepwater ocean areas. The concept has been developed, model tested, and several of the concept components have been utilized in the field.
Several blowouts have occurred which have resulted in oil and/or gas flowing from a subsea well or BOP. The flow, when it reaches the ocean surface, must be collected. The concept reported in this paper diverts the subsea well flow to a collection vessel before the flow reaches the surface. A funnel with riser suspended from a barge is positioned over the subsea well. The well flow, which contains gas, lightens the fluid column inside the riser and the well fluids flow up through the riser to the collection barge. Once the well flow is diverted, a method of entering and stopping the well flow from the well bore is available via the funnel and riser. This complete system, the model tests, the field application, and the future use of the diverting and controlling procedures are reported in this paper.
Effects of Field Wear on PDC Bit Performance
Authors: Cheatham C. A. , Loeb D. A. 
Published: December 2007

ABSTRACT
Laboratory drilling tests were conducted using a new 8 1/2 inch(216 mm) polycrystalline diamond compact (PDC) bit to determine optimum operating conditions for subsequent field use. The bit was then run on rotary in a shale formation at 14 506 ft(4421 m). Rate of penetration measured in the laboratory agreed closely with that observed in the field. Laboratory tests with the field-worn bit showed that to achieve the same rate of penetration as the new bit, the worn bit required three to eight times as much weight-on-bit and two to four times as much torque. Results indicate that, regardless of wear, maximum rotary speed should be used in medium-hard shale to obtain highest rate of penetration.
Long Reach Drilling In the Gulf of Mexico: A Case History
Authors: Whitson C. D. , Sandison G. F. 
Published: December 2007

ABSTRACT
The Gulf Coast Main Pass 30 #1 Wildcat was spudped in November, 1983, and successfully drilled to a depth of 14,828 ft. MD – 7164 ft. TVD (See Figure 1). The average angle was 71° and the total horizontal displacement was 11,255 ft. The well was drilled from a surface location in Breton Sound Block 56 because of restrictions governing the placement of structures in Main Pass 30, which is located in a shipping fairway and anchorage area (See Figure 2 & 3).
The success of long reach well depended primarily upon the development of a thorough well plan and the close monitoring of drilling progress. In planning the well, drilling personnel paid close attention to the directional, casing, mud, surveying, and logging programs. Each was planned to accommodate the severity of the well geometry. Numerous options were considered for each phase before final decisions were made. Recently developed technology was used to great advantage e.g. measurement while drilling tools (MWD), slow speed-straight hole drilling motors, and drill string conveyed logging tools. This paper will outline the approach taken in planning and drilling the well and discuss possible improvements which could be made in future long reach wells.
The Evolution of Arctic Drilling Equipment
Authors: Holley G. T. 
Published: December 2007

ABSTRACT
Since Arctic drilling and production programs in Alaska were undertaken over 20 years ago, the contract drilling industry has met and continues to meet the challenges of remote Arctic areas. Special drilling techniques and equipment have been developed to handle operations in the hostile environment. With most of Alaska's onshore and offshore areas remaining to be explored, the outlook for years of continued drilling looks good with new challenges for the industry ever present.
Water-Soluble Polymer Adsorption from Saline Solutions
Authors: Shah S. , Heinle S. A. , Glass J. E. 
Published: December 2007

ABSTRACT
The adsorption of various polysaccharides on peptized montmorillonite is examined and their influence on the fluid loss properties of polymer-modified bentonite drilling mud (14 lb/bbl) formulations is studied as a function of increasing solution salinity and temperature. The studies indicate that adsorption per se does not facilitate fluid loss control, but adsorption is necessary in saline solutions. The ability of an anionic polymer to effect fluid loss control is related to the nature and amount of anionic substituent in the polymer (i.e., the total ionization of the macromolecule).
Mechanistically the data can be interpreted in terms of minimization of the electrical repulsive forces of the anionically charged water-soluble polymer and montmorillonite surface, with adsorption of the polyelectrolytes on the clay's surface positive edges.
Molecular Size Studies of Degraded Fracturing Fluid Polymers
Authors: Gall B. L. , Raible C. J. 
Published: December 2007

ABSTRACT
Effective degradation of fracturing fluid polymers is necessary to minimize fracture and formation damage to allow rapid fluid return and economic production of gas (and/or oil). In this study, size exclusion chromatography (SEC) was used to investigate degradation of water-soluble polymers, such as modified guar and cellulose polymers.
SEC was used to monitor the decrease in molecular size of the polymer degradation products using oxidant breakers in the temperature range 343 K to 370 K (158°F to 205°F). SEC, however, was capable of monitoring the effects of polymer type and concentration, breaker type and concentration, break time and temperature. The SEC results were then correlated with solution fluid loss characteristics and residue production to define the molecular size reduction needed to minimize damage to a propped fracture. Results were compared to sandpack damage studies reported in the literature. Greater insoluble residue production required greater molecular weight reduction to minimize damage. SEC results were also correlated with solution viscosity. Measured viscosities depended on polymer concentration and degree of polymer degradation. Low solution viscosity did not guarantee reduction of polymer molecules to a non-damaging size.
SEC analysis should also be useful for evaluating new or improved breaker and polymer systems. Presently available breaker systems (in the temperature range of this study) did not provide both high initial solution viscosity and efficient molecular size reduction to minimize damage.
Potential Use of Nonionic Surfactants in Micellar Flooding
Authors: Verkruyse L. A. , Salter S. J. 
Published: December 2007

ABSTRACT
A micellar flood was run in a Berea core using an isomerically pure nonionic surfactant. Phase behavior studies, interfacial tension measurements, and adsorption tests were conducted prior to flooding. High solubilization parameters, low interfacial tensions, and acceptable adsorption values were obtained for this surfactant. Nonetheless, the micellar flood failed to recover the anticipated amount of oil. Compositional analyses of flood effluent indicate that the micellar slug fell apart resulting in an increase in interfacial tensions and significant surfactant loss due to partitioning into the oleic phase.
Laboratory Evaluation of Sodium Hydroxide, Sodium Orthosilicate, and Sodium Metasilicate as Alkaline Flooding Agents for a Western Canada Reservoir
Authors: Larrondo L. E. , Urness C. M. , Milosz G. M. 
Published: December 2007

ABSTRACT
The performance of sodium hydroxide, sodium orthosilicate, and sodium metasilicate solutions in oil recovery was evaluated in displacement tests using core samples and fluids from a Western Canada sandstone oil reservoir. Each core plug was first waterflooded with the formation (produced) brine and then resaturated with the reservoir oil before being treated with a given alkaline solution. The latter was injected either continuously or as a slug. Up to 2 pore volumes injected (PVI) of alkaline solution, 0.3 weight percent sodium hydroxide and 1.0 weight percent sodium metasilicate recovered the largest amount of additional oil. At higher PVI, 0.3 and 1.0 weight percent sodium hydroxide solutions recovered more additional oil than all other solutions. The oil recovery from the alkaline slugs (0.5 to 0.66 PV) was poorer, possibly because most of the alkali injected was consumed through reactions with the rock and reservoir fluids.
Emulsification and interfacial tension measurements as well as alkali consumption data suggest that all of the alkaline solutions used in the displacement tests should have had similar performance. The differences observed in the oil recoveries could be explained in terms of mineral and/or structural heterogeneity of the reservoir rock. In addition, the effects of freezing part of the sample in liquid nitrogen may have played a role in the observed performance of the alkaline solutions.
Prediction of Viscosity for Xanthan Solutions in Brines
Authors: Auerbach M. H. 
Published: December 2007

ABSTRACT
Loss of solution viscosity in brines of increasing ionic strength (salinity/hardness) is a major problem in the use of partially hydrolyzed Polyacrylamides for enhanced oil recovery mobility control. The solution viscosity of xanthan gum polysaccharide, however, is generally accepted to be unaffected by salt content in the water. In fact, recent work by Philips, et al1, has shown that solutions of high-pyruvate xanthan actually increase substantially in viscosity with increasing salt concentration.
Earlier papers by Ward and Martin2 and French, Stacy, and Collins3 reported results of US DOE-sponsored programs to establish relationships between total ionic strength, concentration of calcium or magnesium ion, polymer concentration, and the resulting solution viscosity for partially hydrolyzed Polyacrylamides with varying degree of hydrolysis and molecular weight. This paper presents similar work with xanthan biopolymers of varying pyruvate content. Formulae are given to enable prediction of solution viscosity for a given brine salinity and polymer concentration, and to calculate the polymer concentration needed to give a desired solution viscosity.
For both medium- and high-pyruvate xanthans, solution viscosity increased with increasing brine salinity; the presence of multivalent cations (hardness) had no additional effect on viscosity beyond their contribution to total salinity. For a given polymer concentration, xanthan solution viscosity exceeded that of hydrolyzed polycrylamides above about 0.3% total dissolved salt.
The Operator-Contractor Relationship—Contract Changes, 1982 to 1984
Authors: Warren T. 
Published: December 2007

ABSTRACT
Significant changes in the oil industry have occurred during the last two years which affect both operators and drilling contractors. Operators have experienced declining demand, falling production, an oversupply of natural gas, lower oil and gas prices and the inability of most companies to replace reserves.
Drilling contractors are attempting to survive the bottom of the drilling cycle as rig supply greatly exceeds demand. Low utilization rates of 50-60% produce low prices which are not sufficient to service debt repayment or fully recover equipment replacement costs and result in a significant financial loss. Yet, bankruptcies and foreclosures are slow to reduce the number of available rigs as banks continue to disrupt the normal balancing of supply and demand by supporting contractors who should be leaving the market.
Significant, although less obvious, changes have also occurred in drilling contracts which reflect the major trends of the industry. These contractual changes need to be recognized for the way they affect the services a contractor provides, the allocation of risk, the operator-contractor relationship and the health of the industry.
Stimulating Water-Sensitive Formations at High Reservoir Temperature
Authors: Dietzel H. J. , Von Hantelmann G. A. 
Published: December 2007

ABSTRACT
This paper presents a case history of a MHF-treatment on a deep gas well, situated in the North-German Ostfriesland area. From core analysis the gas-bearing formation was proven to be extremely water-sensitive. In consequence it was essential to eliminate any water content in the treating fluid, so an oil-based gel system had to be selected. To face the BHST of 270 °F (132 °C) high temperature stability of the treating fluid was required. However, the BHST was above the working limit of the gel and consequently a large cool-down pre-pad was necessary. The physical qualities of the base fluid and the rheological properties of the prepared gel system will be described. A description of the frac-design will be followed by the operation history. The use of a hydrocarbon-based treatment fluid combined with a low draw-down concept in the clean-up period resulted in an excellent back-flow performance of the treating fluid. Fracture half-length and fracture flow capacity were deduced from a post-frac pressure build-up.