bluuebunny/crossref_metadata_2025_split huggingface dataset:
Oilfield Theft
Authors: Moss K. E. 
Published: December 2007

ABSTRACT
The cost of oil field theft to the Petroleum Industry and the ultimate consumer is tremendous. Oil field theft should be a concern of everyone connected with the industry. We are going to have to do a better job of protecting ourselves against theft. The successful manager will find and develop ways to avoid theft. The unsuccessful will continue to be "easy pickings" for the thief.
Conservative estimates indicate that oil field theft is costing the Petroleum Industry one and one-half billion dollars per year. Some think that the cost may be as high as 10 billion dollars or more per year. Oil field theft affects everyone of us. For one to assume that he is not touched by oil field crime, is to admit ignorance or that he has his head in the sand.
The problem is present in a small or large degree throughout the Petroleum Industry. There is no area that is immune. The cost to the industry and the consumer is tremendous. Best estimates by government, insurance companies and law enforcement personnel are that oil field theft costs the consumer seventeen cents ($.17) of every dollar that he spends at the pump! Statistical records pertaining to oil field theft are very skimpy. Because our operations are scattered throughout the world and because many of the thefts are not reported, we don't know just how big the problem really is.
Use of Proppant Selection Models To Optimize Fracturing Treatment Designs in Low-Permeability Reservoirs
Authors: Phillips A. M. , Anderson R. W. 
Published: December 2007

ABSTRACT
Low permeability reservoirs are currently being propped with sand, resin coated sand, intermediate propped with sand, resin coated sand, intermediate density proppants and bauxite. This wide range of proppant cost and performance has resulted in the proppant cost and performance has resulted in the proliferation of proppant selection models. Initially, a rather vague relationship between well depth and proppant strength dictated the choice of proppant. More recently, computerized models of proppant. More recently, computerized models of varying complexity have become available which utilize net present value calculations. The input is based on the operator's performance goals for each well and specific reservoir properties. Simpler, non-computerized approaches also being used include cost/performance comparisons and nomographs. Each type of model, including several of the computerized models, will be examined.
Utilizing these models and net present value calculations, optimum fracturing treatment designs have been developed for low permeability reservoirs such as the Prue in Oklahoma. Typical well conditions are used in each of the selection models and the results are compared. The computerized models allow the operator to determine, prior to fracturing, how changes in proppant type, size, and quantity will affect post-frac production over time periods ranging from several months to many years. Thus the operator can choose the fracturing treatment design which best satisfies his economic performance goals for a particular well whether performance goals for a particular well whether those goals be long term or short term oriented.
Hydraulic Fracture Treatment Design of Wells With Multiple Zones
Authors: Ahmed U. , Newberry B. M. , Cannon D. E. 
Published: December 2007

Abstract
In recent years, there have been significant developments in the optimization of hydraulic fracture treatment of wells with one pay zone, but studies concerning treatment in wells with multiple zonesare virtually nonexistent. Because a significant portion, it not a majority, of hydraulic fracture treatments are done in wells with multiple pay zones, discussions are presented to show (1) the use of limited technology leads to uneconomical depletion of the formation and (2) a model for effectively designing fracture treatment for multiple pay zones.
Three field examples are presented to illustrate the various uses of the model in optimizing hydraulic fracturing treatment of wells with multiple zones.
Simulation of Three-Dimensional Propagation of a Vertical Hydraulic Fracture
Authors: Thiercelin M. J. , Ben-Naceur K. , Lemanczyk Z. R. 
Published: December 2007

ABSTRACT
This paper describes a laboratory and numerical study of contained hydraulic fracture propagation via a preexisting stress gradient. This study was conducted in order to improve current knowledge of three-dimensional geometry. Laboratory tests were performed using prefractured polymethylmethacrylate (PMMA) beams which were subjected to a stress gradient in the minimum principal stress direction. The fracture propagation was studied as a function of fluid rheology, flow rate and state of stress. The numerical approach consisted of a pseudo-three-dimensional model, developed to handle any type of boundary condition.
Results show that fracture-shape evolution is close to radial propagation at initiation, but becomes more and more contained as the length increases. A good prediction is achieved once the assumptions of the model are validated, i.e., once the fracture is sufficiently elongated.
Hydraulic Fracture Geometry Modeling, Prediction, and Comparisons
Authors: Advani S. H. , Khattab H. , Lee J. K. 
Published: December 2007

ABSTRACT
Results from an on-going DOE sponsored program related to hydraulic fracture response modeling are presented. Finite element model formulations and the solution methodology associated with a pseudo-three-dimensional hydraulic fracture model coupling fracture fluid flow and leak-off on both horizontal and vertical cross-sections with the elastic response in vertical cross-sections are described. In addition, fracture geometry evaluations and selected comparisons with available results are revealed.
Comprehensive Well Testing and Modeling of Pre- and Post-Fracture Well Performance of the MWX Lenticular Tight Gas Sands
Authors: Branagan P. T. , Cipolla C. L. , Lee S. J. , Wilmer R. H. 
Published: December 2007

ABSTRACT
Well testing and reservoir analysis results from the Department of Energy's Multiwell Experiment (MWX) are presented before and after a set of hydraulic fracturing treatments were performed in two naturally fractured, lenticular Paludal sands of the Mesaverde Group in the Rulison Field, Colorado. The well testing data combined with seismic, core, log, production, and special fracture diagnostics information was integrated into a reservoir model that was used to assess the effects of various reservoir parameters on well performance before and after each fracture treatment.
Production/interference testing and the subsequent reservoir modeling revealed that although hydraulic fracturing produced a highly conductive linear flow path to the wellbore, the productive fracture lengths appeared to be considerably shorter than designed lengths. Furthermore, a post-frac decline in overall production implied a degrading effect upon the flow capacity of the original natural fracture system that was adjacent to the propped fracture. The production/interference testing illustrates the gradual degradation in the near term production capacity of the reservoir from its initial state through two hydraulic fracture treatments.
Geology and Production Performance of the Niobrara Low-Permeability Reservoir in the Denver-Julesburg Basin
Authors: Hollberg J. E. , Dahm M. A. , Bath J. 
Published: December 2007

ABSTRACT
This paper presents geologic and reservoir parameters of the Niobrara Formation in Weld County, Colorado. With the use of computer generated contour maps, it is possible to predict favorable areas of profitable Niobrara pay. This predictability is further enhanced when combined with Scanning Electron Microscopy (SEM) analysis and historical production analysis.
The SEM results show that the Niobrara in this region is a micrite and not a true chalk. The porosity is, therefore, lower than would be expected in a chalk.
The thickness of the second bench and the pore volume appear to have a better relationship to known faults in the Niobrara than present day structure. These parameters were analyzed in order to predict areas of faulting and fracturing, since these areas are known to have the best potential for Niobrara production. Use of these techniques indicates that the northern portion of the study area has the highest potential for successful Niobrara wells.
Based on the limited amount of production history available in this region and current market oil and gas prices, the average Niobrara well in this region appears to be uneconomic unless supported by additional production from other horizons. However, computer mapping suggests that current production is not located in the most promising areas. Greater Niobrara production potential may be found in local areas characterized by greater porosity, thicker benches, and proximity to faults.
Wall Slip Evaluation in Steady Shear Viscosity Measurements of Hydraulic Fracturing Fluids
Authors: Knoll S. K. 
Published: December 2007

ABSTRACT
The rheological properties of hydraulic fracturing fluids, commonly used in low permeability reservoirs, has been discussed extensively in recent years because of their importance in stimulation treatment design. Rheology of these systems is primarily determined in a coaxial cylinder viscometer and reported as apparent viscosity. However, many problems have been encountered in obtaining accurate measurements of crosslinked gels due to the fluid slipping at the solid boundaries of the bob and cup. This slip creates an unknown velocity profile across the flow field; in other words, the fluid experiences an unknown shear. Since viscosity, as well as job design parameters n' and K' are the direct result of shear rate and shear stress, determination of the actual shear rate experienced by the fluid is critical. Many instances have been observed where the steady shear measurements indicate that the fluid has little or no viscosity. Yet, accounting for slip at the walls, the fluid is still a viscous crosslinked gel. Only by determining the existence and extent of wall slip of fracturing systems and how to correct for it, can the steady shear data that are utilized in treatment design models be meaningful.
This paper presents the application of a theory to determine 1). wall slip velocities in a coaxial cylinder viscometer 2). corrected shear rate not based on power law parameters and 3). true viscosity of crosslinked fracturing fluids. Data have been taken over a wide shear rate range to distinquish if wall slip is more prevalent at low or high shear rates. Data also show, that for certain mixing conditions of the polymer and crosslinking reagent, wall slip is very significant and the shear experienced by the fluid is less than expected, resulting in higher viscosity values. Methods of gel testing and preparation have been examined and those methods that minimize wall slip will be discussed. In addition, oscillatory shear measurements, which describe gel structure, are shown to further explain rheological behavior in steady shear. Viscosity values corrected for slip will be compared with viscosity values obtained on a closed loop pipe viscometer.
Proppant Transport by Xanthan and Xanthan-Hydroxypropyl Guar Solutions: Alternatives to Crosslinked Fluids
Authors: Clark P. E. , Halvaci M. , Ghaeli H. , Parks C. F. 
Published: December 2007

ABSTRACT
Proppant transport is of primary importance in the design of new fracturing fluids. In the prediction of proppant settling rates, a wide variation has been found between measured proppant falling rates and those predicted using correlations based on apparent vicosity. Many fracture design computer programs calculate proppant settling rates using calculation procedures which are based on Stokes' Law or some type of power law settling velocity correlation. Much of the experimental data on which these correlations are based were derived from studies of guar, hydroxypropyl guar and hydroxyethyl cellulose. This type of correlation is inadequate to describe the settling behavior in xanthan solutions, foams, emulsions or crosslinked gels.
Data on the proppant settling velocity and rheology of xanthan polymer solutions and xanthan-hydroxypropyl guar mixtures have been gathered to use in the development of correlations for proppant transport. The xanthan-hydroxypropyl guar mixture has excellent proppant carrying capacity over a wide range of temperatures. In fact, a mixture of 15 lb/1000 gal of xanthan with 15 lb/1000 gal hydroxypropyl guar yields comparable particle settling velocities to a 40 lb/1000 gal hydroxypropyl guar solution at room temperature and superior behavior at 150° F. The exact mechanism of the enhanced particle transport by the mixture has not been determined. However, the rheological behavior of the mixture at shear rates of less than 10 s-1 is important and is a shear rate not often considered in current fluid evaluation studies.
The ‘British Argyll’ DSV Wirelining System
Authors: Huber D S , Turner W , Baxter C 
Published: December 2007

Abstract
The wireline servicing of subsea completed wells is expensive and time consuming, as even simple wireline work has always been carried out by semi-submersibles in the North Sea. This paper describes the development of a subsea wireline and surface support system which has been used on a test well in the Argyll Field by the mono-hull diving support vessel, the ‘British Argyll’. The design of the system has evolved over the last three years as a result of close co-operation between Hamilton Brothers, the DSV operator and a major wireline company. The use of such a vessel has the potential to save an oil producer several million dollars per year based on the historical frequency of wireline interventions in a subsea developed field.
Field Experience in the Bothamsall Surfactant Flood Project
Authors: Cooper M N , Southworth R A , Walsh D M , Morgan J C 
Published: December 2007

ABSTRACT
A low concentration surfactant flood was initiated in the Bothamsall Field in July 1983. The test area is described and the design of the project is discussed. The methods used to control surfactant injection and the steps taken to monitor produced fluids to assess the performance of the flood are described. Valuable experience has been gained both in the handling and injection of surfactant solutions and in the treatment of surfactant-stabilised oil-in-water emulsions. The initial production profiles for the surfactant flood are presented. The data required to make a complete evaluation of the response of the test area to surfactant injection are still being gathered.
Experience of Perforation Under Drawdown Using Tubing Conveyed Guns on the Beatrice Field
Authors: Allan J. C. , Moore P. C. , Weighill G. T. 
Published: December 2007

SUMMARY
This paper describes the perforation, under drawdown, of Beatrice production wells. In view of the long completion intervals, tubing conveyed perforating guns are used.
A technique has been developed which enables perforation to be carried out under controlled underbalance conditions and allows well clean-up by means of a subsequent free-flow period. This, together with a pressure build-up, enables the well productivity index to be determined, and hence aids sizing of the electrical submersible pump. This is necessary to ensure that the pump operates within its recommended range.
To date, nine production wells have been perforated using tubing conveyed guns. It is shown that this technique has resulted in a significant improvement in productivity when compared to wells which have been perforated overbalanced. It is likely that this also enhances the life of the electrical submersible pump by reducing the pump loading.
Underwater Inspection and Surveys Using Computer Management
Authors: Mills G. , Ball D. 
Published: December 2007

ABSTRACT
Mandatory underwater inspection programmes are expensive and generate large volumes of report material. Computer based systems have been developed to provide more efficient and flexible planning of these programmes, to facilitate report production and, most significantly to allow the management of the results of such inspections including trend analysis, summary reports, defect or reading ranking and so forth.
This paper will briefly review current common inspection techniques used underwater and detail how a computer aided inspection planning and reporting system was designed to satisfy the needs of underwater inspection. The basic philosophy of the system has been incorporated into six systems which have now been specifically tailored to oil companies' requirements, including one system for pipeline surveys which incorporates automatic transfer of information from the pipeline survey data processing computer system.
Such systems, which are in use today, could lead to fully automatic inspection surveys, from sensors to finally assembled report and this potential is discussed, together with other applications such as above water offshore inspection and inspection control during fabrication. The advantages of computer aided inspection reporting are explained, including the potential for cost savings during inspections and examples for where these have been achieved in reality.
The Simulation of Phase Behavior and Slim-Tube Displacements with Equations of State
Authors: Kossack C. A. , Hagen S. 
Published: December 2007

ABSTRACT
In compositional reservoir simulation the ability of an Equation of State to accurately model the phase behavior is evaluated for both the Peng-Robinson and Soave-Redlich-Kwong Equations of State. The analysis was performed with pure component systems to circumvent the problem of pseudo-components and to allow a comparison of calculated ternary diagrams with literature values. The initial work was performed with the binary system of methane and n-decane. The relative permeability of the slim tube was determined by the history matching of an immiscible slim tube displacement. The Equations of State were able to simulate the two-component displacements. PVT experiments were run with the three-component system of methane-propane-n-decane to provide data for a phase match of the Equations of State. The Equations of State with these phase matches were not able to simulate the multiple contact miscibility displacements in a slim tube. The sensitivity of the calculated results to the binary interaction coefficients and to the number of numerical grid blocks was studied.
Oilfield Cashflow: The Independents' Lifeblood for Survival
Authors: Chan S. A. 
Published: December 2007

ABSTRACT
Independent producers are under increasing pressure to seek out every available dollar of internally generated cashflow from otherwise idle assets or premature financial obligations. Many petroleum companies can better manage their existing operations to improve their performances through cash management, updated collection policies, cash processing and disbursements, short term investments, and more accurate planning. Using the analytical capabilities of micro-computers, examples of the benefits of applying financial management techniques are illustrated in terms of increased working capital, added profitability and strengthened cashflow.
Development of Field-Size Distribution for Undiscovered Hydrocarbon Resources in the Lower 48
Authors: Woods T. J. , Duleep K. G. , Vidas E. H. 
Published: December 2007

ABSTRACT
Analyses of exploration history have indicated anomalous increases in finding rates for many field sizes as the resource base is depleted. The anomaly is a wide-spread phenomenon, and it cannot be explained in terms of the general form of the Arps-Roberts find-rate equation. A modified Arps-Roberts equation has been developed that replicates historical discovery patterns and provides a basis whereby the anomaly can be explained. Using the modified Arps-Roberts equation, we have developed estimates of the remaining undiscovered lower 48 hydrocarbon resource base, apportioned among field sizes. The resulting field size distributions provide some insights into lower 48 hydrocarbon resource estimates, such as those by the U.S. Geological Survey and the Potential Gas Committee. Some insights into general exploration success patterns can also be obtained.
Application of the modified Arps-Roberts find-rate equation to estimate the cost to discover and produce the remaining undiscovered hydrocarbon resource base indicates that a substantial part of the remaining resource would be uneconomic to discover and produce. The major part of this residual resource base is comprised of fields that are currently economic targets.
How the Portfolio Approach Aids Exploration Strategic Planning
Authors: Jones W. A. 
Published: December 2007

ABSTRACT
The objective of this paper is to demonstrate the numerous advantages of the use of portfolio theory in the analysis of exploration opportunities and options. The principal benefits of the Portfolio Approach to Exploration Strategic Planning can be divided into two categories: those benefits in dealing with corporate management and those in developing the exploration strategies themselves.
A simple case study has been developed using a computer model. The study will follow an Exploration Program through the three stages of an annual cycle: evaluation, improvement, and tracking. The study will also be used to demonstrate the advantages of the Portfolio Approach in developing basin/play strategies.
A Simulation Approach to Viability Analysis
Authors: Garibaldi C. A. , Iskander F. F. 
Published: December 2007

ABSTRACT
Two issues in risk analysis are studied. First, a simple method is developed for making consistent risk adjustments to the expected present value of profits, considering capital exposure and attitude toward risk. Next, a Monte-Carlo simulation model is developed to perform viability analysis and, thus, adjust for risk a realistic and operative distribution of results.
Recent Design, Placement, and Evaluation Techniques Lead to Improved Gravel Pack Performance
Authors: Ledlow L. B. , Sauer C. W. , Till M. V. 
Published: December 2007

ABSTRACT
Gravel packing has been the method of choice for sand control for the last 40–50 years. Historically gravel packs have impaired the productivity of sand controlled well completions. Only recently through the use of Well Flow, Nodal or Systems Analysis1,2 has the technology from perforating, formation damage prevention, and gravel pack design been assembled in order to effectively understand these damage mechanisms. On-site supervision and execution of better designs is crucial to sand control success. Better gravel placement, downhole tools, and planning have enhanced our ability to execute, these designs.