bluuebunny/crossref_metadata_2025_split huggingface dataset:
Continuous Oil in Water Measurement
Authors: Frost M. , Huber E. E. 
Published: December 2007

Abstract
Oil in wastewater causes environmental problems. The official control method of its content is, at present, done by extraction and subsequent measurement via IR absorption. There has been an increasing interest in continuous measurements. The method discussed in this paper is fluorescence measurement. The molecules of many oil components are exited in the UV and yield fluorescent light in the VIS range. The "sum parameter" of fluorescence is neither identical with that of IR measurement nor that of the total oil mass. Thus, these data correlate only if the composition of the oil does not change drastically. That means in general that a calibration is good only for one specific oil and for the corresponding drilling site. A factory calibration is discussed and compared with the situation on site. It will be shown which measuring ranges are realistic for this method. An optical schematic of a dual beam fluorescence photometer for continuous oil measurements is introduced. This setup allows drift flee measurement and accounts for interferences of solids in a moderate concentration. A solution to prevent finding and the required steps are introduced.
Hudson - A Phased Field Development
Authors: Lane R. L. , Currie S. , Scott G. C. , Woods J. S. 
Published: December 2007

Abstract
This paper describes the two phase development of the Hudson field and the production performance in Phase I that was used to modify the development plan. The paper follows field development into the first months of Phase II and covers plans for future reservoir management.
Like many current and future Northern North Sea developments, the Hudson field is relatively small and within reach of existing infrastructure (figure 1). Limited appraisal data and the desire to limit up front capital expenditure (CAPEX) led to an innovative phased development concept with early cash flow from leased production facilities funding the later full field exploitation. Reservoir data gathered in Phase I would be used to optimise the Phase II expansion.
The highly successful Phase I development was from 2 wells producing to the Petrojarl I floating production storage and offtake vessel. There was no water injection. Results yielded information about aquifer connectivity, geological layering and well deliverability that have influenced several aspects of the development plan in addition to producing 17.5 mmstb of oil to fund the remainder of the project.
Real Time Stimulation Evaluation in Deepwater Well Completions
Authors: Morgenthaler Lee N. , Malochee Sharon B. , Smith Chris D. 
Published: December 2007

Abstract
Shell Offshore Inc.'s (SOI) Auger tension leg platform was installed in 2860 feet of water, 215 miles southwest of New Orleans. Nine producing wells were completed during 1994. These well completions presented many unique challenges which have been documented elsewhere.1,2 Paramount among these was the requirement that each well produce at high rates of at least 6000 BOPD in order to make the project economically viable. To yield the desired rates, efficient completions were essential.
Although the target completion intervals at Auger were very deep (&gt;20,000 ft measured depth), the unconsolidated and uncemented nature of the turbidite sands made sand control necessary. In these deep, geopressured, long (&gt;150 ft) interval completions, acid stimulation was used extensively. Because of the critical nature of these wells, industry's best practices and up-to-date technology were applied to ensure effective stimulation. With respect to acid stimulation, this meant application of Paccaloni's3,4 concepts for treatment design, coupled with real time monitoring of treating data. In this report, we will show how these processes combined to achieve our productivity objectives.
Paccaloni's design concepts were used here to scale treatment volumes, rates, and diversion strategies to anticipated well productivity. The design objective is to pump sufficient acid to remove near wellbore damage from the entire completion interval. Maintaining wellbore treating pressure as high as possible without fracturing maximizes acid injection into damaged zones. It is essential to avoid fracturing to maintain injection control. This can be accomplished by maintaining a high injection rate, increasing acid viscosity, or applying diverters. All three approaches were combined in the Auger designs.
Estimating Fracture Geometry in the Naturally Fractured Antrim Shale
Authors: Hopkins C. W. , Frantz J. H. , Hill D. G. , Zamora F. 
Published: December 2007

Abstract
The Antrim Shale of the Michigan Basin has been an active gas play with over 3,500 wells drilled over the last 5 years. There is substantial evidence that the Antrim must be fracture stimulated to be economical and that two-stage treatments provide the best results. However, due to the shallow depths (500-2300 ft) and naturally fractured nature of the Antrim, fracture geometry is complex, and determination of optimal fracture treatments is not straight forward. Because historical field comparisons did not provide insight on the optimal fracture treatments, the Gas Research Institute (GRI) instituted a field-based project for the specific purpose of evaluating the geometry of hydraulic fractures in the Antrim.
Open- and cased-hole tests were performed on two separate Antrim wells - a shallow producer (600 +/- ft) and a deep producer (1550 +\- ft). Open-hole testing and data collection consisted of in-situ stress and mechanical property testing with Halliburton’s THE™ Tool (9 tests) and a detailed suite of geophysical logs including dipole sonic logs and natural fracture detection logs. Cased-hole testing consisted of pre-and post-fracture injection/falloff tests, minifracture treatments, multiple isotope tracer and tracer logs, and treating pressure and production data analysis.
Analysis of open- and cased-hole data from the shallow and deep wells suggests that subvertical fractures are being created and are probably following existing natural fracture planes. The shallow depths, low in-situ stresses, and extremely fractured nature of the Antrim probably results in the preferential opening of existing fractures instead of the creation of new fracture planes. As a result, the creation of multiple fractures and severe near wellbore tortuosity is likely. Therefore, the natural fractures are responsible for increased leakoff and will greatly impact created fracture geometry. The results also suggest that creating long propped hydraulic fractures in the Antrim is not likely due to the creation of multiple fractures.
An MWD Downhole Assistant Driller
Authors: Hutchinson Mark , Dubinsky Vladimir , Henneuse Henry 
Published: December 2007

Abstract
Identification of drilling problems is most commonly achieved by simple comparisons of surface and downhole time-averaged measurements of weight and torque, or by shock and vibration sensors located either downhole or at the surface. Various drilling phenomena are more complex than can be described by these simple shock and vibration measurements. The interpretation of drilling vibration data collected at the surface requires specialized expertise, and can be difficult. Sometimes downhole phenomena are not interpretable at the surface. The diagnosis of bottom hole assembly (BHA) vibrations measured directly by a downhole tool is much easier.
A prototype downhole assistant driller measurement-while-drilling (MWD) device has been constructed that unambiguously diagnoses drilling phenomena from sensors that are located in the BHA, and that are sampled at a high frequency. Processing algorithms programmed into the prototype identify bit bounce, stick-slip, backward rotation, torque shocks, BHA whirl, pressure anomalies and excessive stress. Drilling efficiency and specific energy at the bit are also calculated. Average weight and torque values as well as drilling diagnostics are transmitted to the surface and enable the driller to make real-time improvements to the drilling process in a timely manner.
A key requirement for enhancing drilling performance is the ability to simply and clearly display information about the drilling process on the rig floor. The prototype display not only informs the driller about the severity of drilling phenomena, but also provides advice about how to eliminate particular drilling inefficiencies before they become problematic. The real-time drill floor display effectively completes the loop between the MWD prototype in the bottom hole assembly and the driller's controls. Additional displays and logs permit the post-drilling assessment of data from previously drilled intervals.
The downhole assistant driller helps optimize the rate of penetration, and reduce bit, motor, MWD and other BHA component failures. Downhole drilling parameters, together with quality conventional surface measurements, identify drilling problems and help drillers better decide when to make short wiper runs, or when to trip for a bit.
A method for closed-loop drilling operations is presented. This paper reviews the test program and draws conclusions from long term research with both downhole and surface drilling measurements. Actual field results demonstrate how downhole measurements provide a clearer feel for BHA behavior, and allow the driller to optimize the drilling process, reduce BHA component damage, and improve the efficiency of the drilling operation.
Improved Formation Evaluaton Using Azimuthal Porosity Data While Drilling
Authors: Evans M. , Best D. , Holenka J. , Kurkoski P. , Sloan W. 
Published: December 2007

Abstract
Measurement of formation porosity and lithology in azimuthal quadrants around the borehole is now available. This new information is provided by a nuclear tool that makes azimuthal density, photoelectric factor and neutron porosity measurements while drilling. In addition, an ultrasonic sensor provides a tool standoff measurement in each quadrant. While rotating, the quadrants are defined by a magnetometer and oriented with the gravity vector, so that bottom, left, right and top quadrants are identified.
The tool can be run with several different stabilizer sizes or without a stabilizer, giving the driller more latitude in configuring the bottomhole assembly. The azimuthal capability allows the measurement of porosity with an unstabilized or "slick" tool without degradation of the measurement. This is accomplished by computing the porosity from the bottom quadrant where there is little tool standoff in deviated or horizontal wells. Utilizing bottom quadrant porosities also results in improved measurement accuracy in cases where borehole conditions are poor due to enlargement or washouts.
When the tool is stabilized, the quadrant porosity and lithology measurements result in improved geosteering as well as providing a quantitative measure of formation heterogeneity. At bed boundaries, comparison of top and bottom logs in real time results in better bed boundary detection and confirmation of the tool location within the pay zone, When the tool is between boundaries, an heterogeneity indicator can be computed from the quadrant density, lithology and neutron porosity logs to better evaluate complex formations.
The measurement of tool standoff per quadrant provides information on borehole size, shape and rugosity. The data can be used to indicate borehole stability on subsequent bit trips.
The paper describes the method of the measurement, hardware implementation and log examples illustrating the tool features.
A New Simplified Approach of Controlling Properties Of Invert Emulsion Drilling Fluids at the Well Site
Authors: Sinha B.K. 
Published: December 2007

Abstract
This paper points out some of the limitations of the present day testing procedures commonly in use and procedures commonly in use and describes a method used to obtain more meaningful data to control the properties of a fluid at a desired properties of a fluid at a desired optimum level with conventional equipment.
The retort unit which measures the volumetric percentages of oil, water and solids in a mud has been found to be most useful. Experimental data obtained using this equipment fall within the experimental error range of the calculated volumetric percentages of oil, water and solids percentages of oil, water and solids for muds of different densities.
As the oil-water ratio of an invert emulsion drilling fluid is increased, the density of the liquid phase (oil and water) decreases. The volume percent solid contribution from the percent solid contribution from the dissolved salt (NaCl) in the water phase to the total retorted solids phase to the total retorted solids percentage of the system also decreases. percentage of the system also decreases. Therefore, to maintain a constant mud density, additional amounts of barite are needed as the oil-water ratio is increased. Any change in the volume percent of salt caused by an alteration percent of salt caused by an alteration of the oil-water ratio is approximately balanced by a corresponding change in the volume percent of barite.
Thus, a linear relationship between the volume percent solids and mud density is obtained which is practically independent of the amount practically independent of the amount of oil and water in the system. Representation of the above relationship in a graphical form has been proven to be of valuable assistance in controlling the properties of invert emulsion drilling fluid at the well site.
It has been observed both in the laboratory and in the field that by maintaining the percentages of oil, water and solids within a specified range, all the measured properties (rheological, fluid loss and electrical stability) fall automatically within the desired range when measured under identical conditions.
Moxa Arch Frontier Development Success Through Increased Fracture Conductivity – Part 2
Authors: Schubarth S. K. , Chabaud R. A. , Penny G. S. 
Published: December 2007

Abstract
Successful development of the Frontier formation in southwest Wyoming begins with the hydraulic fracture treatment design and implementation. Without a design to effectively stimulate the Frontier formation and a proper implementation of that design in the field, production rates will be limited. This paper will describe the results from an extensive drilling and completion program conducted by Bannon Energy Incorporated in the Frontier formation on the Moxa Arch.
Information from over 100 fracture treatments and the production response from over 550 wells will be used to demonstrate the significant improvement in gas production resulting from the fracture treatment designs and implementation methods employed. The effect of fracture conductivity on gas recovery from this formation will be demonstrated along with the effect of multi-phase flow on fracture conductivity.
Cybernetics, A New Method Proposed For Estimating Performance Of Water Driven Reservoirs
Authors: Caseli Umberto Antonio , Crawford Paul B. 
Published: December 2007

Abstract
Cybernetics has been under development for almost 50 years but only during the past 20 years has it evolved into a scientific approach to aid in the analysis of systems existing in the so-called "black box". Petroleum reservoirs are always in the black Petroleum reservoirs are always in the black box category in that the precise reservoir shape, rock and fluid physical properties are never really known even though the reservoir is produced to abandonment.
Cybernetics has been applied to a water-drive reservoir near abandonment conditions. The cybernetic method was found to forecast the performance of this reservoir quite accurately when only a small fraction of the fluid had been produced. Cybernetics does not require detailed information such as rock porosity, permeability, areas, thickness, fluid porosity, permeability, areas, thickness, fluid compressibilities, etc., desired for the conventional influx calculation.

Introduction
In the past 30 years the science of petroleum reservoir engineering has emerged petroleum reservoir engineering has emerged as a well-defined and highly technical branch of petroleum engineering. Extensive investments in facilities and personnel for the recovery of oil and gas are now made routinely on the basis of reservoir performances predicted by reservoir engineering studies. Reservoir engineers and research investigators are pioneering and developing new techniques for pioneering and developing new techniques for improving recovery of oil and gas. Greater accuracy in reservoir performance calculations will bring the industry closer to the ultimate goal of obtaining the maximum efficiency in the exploitation of petroleum reservoirs.
The van Everdingen and Hurst technique of estimating performance of water-drive reservoirs based on compressible flow theory has been presented in the literature as the most generally successful. However, their method applies to radial reservoirs surrounded by infinite or radial aquifers of constant rock and fluid properties. k complete knowledge of the properties of the reservoir and aquifer is desired for applying the technique. The method also requires knowledge of the pressures at the boundary of the reservoir and quifer. Average reservoir pressures are usually used when the boundary pressures are not known.
In practice, besides incomplete knowledge of reservoir properties, there is uncertainty in the aquifer properties, which are generally estimated from wells drilled in the reservoir. On the other hand, there exists uncertainty in the reservoir pressure history. Thus, all of these factors combined contribute to make the van Everdingen and Hurst technique of limited value in many practical cases.
Directional Drilling and Circular Arc Deflection Of Long Beams
Authors: Dareing D.W. , Godhwani Shyam 
Published: December 2007

Abstract
This paper is concerned with the mathematical development and solution of a nonlinear differential equation of bending which relates to the directional drilling of oil and gas wells. The directional drilling concept in this paper is unique and is based on the premise that a directional wellbore having constant curvature will be drilled if the deflection of the bottom portion of the pipe [or drillstring] has portion of the pipe [or drillstring] has constant curvature; the constant curvature or circular arc deflection is due primarily to gravity. To achieve a circular arc pipe deflection due primarily to gravity, pipe diameter must vary along the pipe according to the solution to the differential equation of bending; pipe diameter is the dependent parameter in the pipe diameter is the dependent parameter in the differential equation. The broader purpose of the research is to develop directional drilling technology which relates the many drilling variables, such as bit weight, drilling fluid, and drill collar design, to wellbore geometry.

Introduction
It is sometimes desirable, when drilling for oil, to drill away from the vertical so that the bottom end of the well is at some appreciable horizontal distance away from the vertical. Wells of this geometry are called "directional" wells and are sometimes drilled from offshore platforms to reduce the number of offshore structures in a particular oil field. particular oil field. At the present, directional wells are drilled somewhat by the trial-and-error method, i.e., measurements of drill bit orientation are made periodically and appropriate changes are made in weight on the drill bit to increase or decrease the orientation of the bit. Stabilizers are also used near the bit to control the rate of hole deviation from the vertical.
There are several articles in the literature which discuss directional drilling [and hole deviation, crooked holes, dog-legs, etc.]; however, except for very few technical papers most of the publications are general discussions of the directional drilling problem. A literature survey indicated there are very few, if any, technical publications which relate drilling variables to wellbore curvature. This report represents an attempt to develop a directional drilling technology which relates drilling variables to wellbore curvature.
The directional drilling concept discussed in this report is based on the premise that a wellbore having constant curvature will be drilled if the deflection of the drill pipe directly above the bit is always circular. The circular arc deflection is developed in the section of pipe directly above the bit by using nonuniform pipe whose diameter [or cross-sectional moment of inertia] varies over its length according to the theory presented in this paper.
Behavior of Anisotropic Rocks under Combined Stresses
Authors: Yang J.H. , Gray K.E. 
Published: December 2007

Abstract
Torsional strength tests on slate and Green River shale were performed at various orientations of the cleavage or bedding planes and at various states of stress to study the strength-deformation behavior of anisotropic rocks. The strength characteristics of the rocks, as a function of both the state of stress and the orientation of anisotropy, were determined by twisting cylindrical specimens at a constant rate of 0.1 radian/min. under confining pressures of 5,000 to 30,000 psi, with pore pressure held constant at atmospheric pressure, and under axial loads of 0 to 10,000 pressure, and under axial loads of 0 to 10,000 psi. Samples having an orientation of the plane psi. Samples having an orientation of the plane of anisotropy relative to the cylindrical axis of 0, 30, 45, 60 and 90 degrees were used.
In general, torsional failure strength of the rocks studied increased with mean pressure; the strength was a function of the initial state of stress and the orientation of the plane of anisotropy. Several failure criteria for anisotropic rocks were discussed and compared with experimental data. It was found that current failure criteria could be applied with some degree of success to experimentally generated data.
The orientation of the maximum and minimum torsional strength for both rocks were found to be independent of the initial stress state studies. The failure angle was affected by anisotropy for cleavage or bedding plane over a limited range of orientations. The failure angle was also affected by the initial state of stress. The average modulus of rigidity increased with increasing confining pressure and decreased with axial compressive load. The cohesive strength and the coefficient of internal friction varied with the orientation, and the specific variance was a function of the type of anisotropy.

Introduction
The fundamental problem of rock mechanics in drilling is to determine the state of stress necessary to cause failure. Unfortunately, the failure mechanisms and strength characteristics of rock are not constant. They depend upon rock type, pressure, temperature, strain rate, foliation, type of loading and presence of pore fluid. Therefore, a better understanding of the aspects which govern rock failure may contribute to the solution of drilling and fracturing problems.
Early works by von Karmon and Boker [cf. Nadai], Robertson, Griggs, Handin, Heard, Robinson and Serdengecti have provided considerable information about the effects of temperature, rate of loading and confining and pore pressures on the mechanical behavior of rocks. Inhomogeneity and anisotropy are inherent in the process of sedimentation.