bluuebunny/crossref_metadata_2025 huggingface dataset:
A Revised M.S. Program--Three Years Hence
Authors: Donahue D.A.T. , Ali S.M. Farouq
Published: December 2007

American Institute of Mining, Metallurgical, and Petroleum Engineers, Inc.

Discussion of this paper is invited. Three copies of any discussion should be sent to the Society of Petroleum Engineers office. Such discussion may be presented at the above meeting and, with the paper, may be considered for publication in one of the two SPE magazines.

In order to revise our M.S. degree curriculum so that students completing the program would be prepared to handle both current and future research prepared to handle both current and future research and development assignments especially those in reservoir mechanics, a thorough review of all pertinent curricula was made and the views of pertinent curricula was made and the views of engineering educators were considered. The developed program has been in effect now for three years with several new courses added in the interim. An outline of the revised program is presented in this paper along with the raison d'etre for each course, student reaction and assimulation to the program, and subsequent course modification.

Introduction

"There is only one way out of all this:it is, of course, by rethinking our education." C. P. Snow

In the fall of 1964 members of the faculty of the Department of Petroleum and Natural Gas at the Pennsylvania State University decided that the M.S. program should be critically reviewed and updated if the need for revision was justified. The task was given to the author of this paper. After some degree of discussion, review, reading and thought, a report was written encompassing a revised M.S. program which met with the approval of the program which met with the approval of the departmental faculty. The program was put into effect in 1965 and the results have been viewed with either satisfaction or further revision since that time. However, word of the above report, it's nature and completeness soon reached members of the academic community and requests for copies followed. Because of subsequent response, it was felt that a paper, outlining the revised program, might be of wider interests. This paper has been written to satisfy that interest. The report contains much material which is of value only to the department and, accordingly, has been deleted from this paper. On the other hand, much that was in the report will be found in this paper.

For several years now petroleum engineering educators and specialists have been expressing ever-growing concern over the quality and scope of the current petroleum engineering education in this country.
A Microbial Approach to Cleaning Used Oil-Based Drilling Muds
Authors: Thurman N. P. , Heydeman M. T.
Published: December 2007

It is important for the oil industry to anticipate the restriction of the dumping of oil-containing waste at sea. This paper describes research into the use of micro-organisms to disperse and biodegrade the oil component of cuttings and spent drilling muds before discharge. Bacteria using diesel fuel have been isolated from natural sources. Conditions appropriate to the treatment of oil based muds have been developed using an air lift fermenter. Already selected organisms can degrade in less than two days 100% of many alkanes, 63% of pristane and 46% of phytane originally in the mud. Work is continuing to optimize physical and chemical conditions.
Recent Developments in Pipefreezing Technology for the Oil Industry
Authors: Burton M. J. , Bishop C. W.
Published: December 2007

This paper describes two advances in the pipefreezing technology, now available to offshore installation operators. Flexible vacuum insulated liquid nitrogen transfer lines may now be used to feed freeze jackets located in inaccessible places and to improve the security of coolant supply generally. The development of the heat flux monitoring system allows the progress of a freeze to be followed, close-off of the plug confirmed and the condition of the plug to be monitored. The practical application of both these new developments is illustrated with examples.
Integrated Study of the Kraka Field
Authors: Jørgensen L. N. , Andersen P. M.
Published: December 2007

The Kraka Field, discovered in 1966, was the first oil discovery in the North Sea. The field, a large elongated chalk structure, is located in the southern part of the Central Trough in the Danish sector of the North Sea.

The Kraka field is characterized by a low permeability matrix with some enhancement of permeability due to natural fracturing. The fluid distribution in the reservoir is complex. Throughout the hydrocarbon bearing zone, matrix water saturations are in excess of 50 %. Fluid contacts are tilted, the matrix oil water contact due to tectonics and the fracture free water level due to a regional hydrodynamic gradient. Variations in pressures and fluid properties further add to the complexity of the field.

This paper describes an integrated study of the Kraka field. The integration of a geological fracture study with a reservoir simulation study has resulted in an improved reservoir characterization.

The development history of the field demonstrates how new technology can promote the development of a marginal field.
Snorre Field TLP Rigid Riser System: An Overview
Authors: Lim F. K. , Manning B. V. G. , Alfstad O.
Published: December 2007

This paper presents an overview of the rigid riser system for the Snorre field TLP in the North Sea. The system and components are described to highlight the major design challenges and solutions that have been arrived at to meet the statutory regulations and design requirements.
Quantitative Determination of Solids Invasion and Formation Damage Using CAT Scan and Barite Suspensions
Authors: Krilov Z. , Steiner I. , Goricnik B. , Wojtanowicz A. J. , Cabrajac S.
Published: December 2007

Presented are results the of an experimental study of formation permeability damage caused by invasion of the inert and extraneous solids simulated by barite particles. The use of barite facilitated X-ray computer assisted tomography (CAT) analysis of solids in the rock (determination of penetration distance) is employed because of the method's high resolution to barium.

Laboratory flow tests were performed using two types of sandstone cores: outcrop-clay free, and low clay content cores from oil bearing formations. The cores were analyzed using SEM, XRD, and pore size distribution. Particle size distribution of barite suspended in the influent NaCl brine and effluent was measured by particle size (laser PSA) analysis.

The prevailing mechanism of particle capture and subsequent permeability reduction under the test conditions was found to be cake forming (particle straining) mechanism.

The depth of invading barite solids penetration was detected and quantified by consecutive CAT scanning of core samples during rock damage tests. The preliminary experimental data presented show that CAT scanning technique could be used in more detailed studies of formation damage phenomena employing barite particles.
Development and Field Testing of a Novel Fracturing Fluid
Authors: Davies D. R. , Lau H. C. , Kamphuis H. , Roodhart L. P.
Published: December 2007

A new polymer has been introduced into the oilfield for use in hydraulic fracturing. Its unique properties complement the wide range of polymers currently in use. This biopolymer was originally developed for enhanced oil recovery and is now also used for gravel packing and as a mud Viscosifier.

The biopolymer causes minimal formation/proppant-pack permeability impairment - yielding the highest retained permeabilities of any polymer tested to date. It exhibits a constant viscosity up to a transition temperature (adjustable between 40°C and 100°C) beyond which the viscosity decreases to a level close to that of water. This eliminates the need for a breaker. The polymer is highly shear-thinning, resulting in the lowest tubing-head pressure of all fluids available. The good proppant-carrying capacity of the fluid is achieved without the addition of a crosslinker while fluid loss is similar to other polymers that are commonly used for fracturing.

The formulation of a fully functional fracturing fluid for use at medium temperatures without the need for a breaker or crosslinker is unique. In particular, it can be used with resin-coated proppants where unwanted side reactions occur with conventional fracturing fluids

The new fracturing fluid was successfully tested in combination with resin-coated proppant in the Southern North Sea.
An Improved Kick Detection System for Floating Rigs
Authors: Jardine S. I. , McCann D. P. , White D. B. , Blake A. J.
Published: December 2007

Early detection of fluid influx from the formation (generally known as a "kick") is a key consideration for rig safety. The first indication of many kicks is given by a comparison of flow-in and flow-out of the well being drilled. Accurate flow measurement is therefore of crucial importance to the drilling industry. The heave motion of a floating rig, however, produces large instantaneous variation in flow-out. These fluctuations can simply be averaged over several heave periods but this leads to a delay in detecting an influx.

This paper describes a new approach to obtain an improved flow-out indication by utilising measurements of rig movement in order to predict expected flow variations. This information is used to adaptively compensate flow-out readings from existing sensors for the effects of rig motion to provide a more accurate measure of the instantaneous flow from the well. The technique has been incorporated in a drilling contractor's computerised monitoring and alarm system which displays the compensated measurements in realtime and automatically warns the driller and other key personnel of any influx or loss.

Field examples are presented to illustrate the effectiveness of the system and to show that a reliable alarm warns of changes in flow-out before they would normally be apparent with existing detection systems.
Advances in Forties Field Water Injection
Authors: Simpson A. J. , Paige R. W.
Published: December 2007

The Forties Field sea water injection system was commissioned in 1976 and rapidly achieved design injection capacity of 450,000 bwpd at 80 bar WHIP [71,500 m3/d @ 8 MPa]. The system originally incorporated a cartridge type fine filtration system. In recent years our understanding of both water injection and water quality effects has advanced such that the fine filters were removed during 1989 and 1990. No adverse effects have been experienced or are anticipated. It was recognised that well performance when injecting fine solids or emulsions would depend on the state of the formation around the wellbore. Well-pulsing techniques were used to demonstrate the existence of fractures or cavities in the poorly-consolidated sandstone of the formation. Results suggested that changes in injected water quality did not lead to fracture growth. Some additional information indicating the degree of formation disturbance around the wellbore was provided by analysis of step rate and pressure fall-off tests.

We also report on the results of sustained produced water re-injection into the Forties reservoir. A pilot reinjection trial was conducted in 1985. Produced water was injected into a Forties well at 12,000 bwpd, 89 bar WHIP [1,900 m3/d @ 8.9 MPa] for 6 weeks. The oil in water content varied from 501200 ppm [50-1200 cm3/m3] but there was no evidence of injectivity impairment throughout the trial.

Based on the success of the 1985 trial, a long term reinjection test was initiated on the same well in March 1989. Injection performance was initially difficult to analyse due to persistent pump seal failures, control system problems and, at times, a lack of sufficient produced water. However an injectivity decline of 20-30% was established and various damage and stimulation effects have been investigated.
A Total System Approach to Sweet Gas Corrosion Control by Inhibition
Authors: Argent C. J. , Kokoszka C. L. , Dale M. J. , Hindmarsh M. W.
Published: December 2007

This paper describes an integrated approach to inhibitor assessment and selection for sweet gas corrosion control. A laboratory evaluation programme is described based on criteria which include production system compatability (process/materials), critical inhibitor properties and corrosion control efficiency under normal operating conditions and those when protection may be impaired.
Evaluation of Not Normally Manned Platform Development Concepts
Authors: King S. D. J. , Lucas-Clements D. C. N.
Published: December 2007

A method for the evaluation of unmanned oil and gas development concepts is presented.

Production – average and variability – is calculated to capture development concept revenue risks; manning logistics to prove operability and quantify OPEX. The life cycle simulation method accounts for equipment reliability, maintenance logistics, and operational constraints such as CSON 58.1
A Novel Approach to Exploration Risk Analysis
Authors: Cairns R. J. R.
Published: December 2007

The Achilles' heel of risk analysis is the inability to ascribe probabilities with the required degree of precision. In this paper, a novel approach to the problem of decision making under uncertainty is elucidated. It uses three basic key parameters – the cost to failure, the value of success, the technical evaluation – common to all exploration plays and a derived parameter, the reward to risk ratio as a boundary or go/no go parameter.

It addresses two distinct decision making problems – the specific opportunity and the assignment of priorities. For the latter, a ranking method is used and explained in detail. Ways to extend the methodology to other situations are indicated.

Finally, the benefits of this approach, compared with the widely used Risk Analysis, are enumerated.
Motion Sickness in TEMPSC: Comparison of Abandonment and Training
Authors: Brooke S. T. , Greenen M. G. , Light I. M.
Published: December 2007

The Totally Enclosed Motor Propelled Survival Craft (TEMPSC) is potentially a very provocative factor in the development of motion sickness. Its inherent design characteristics can provide a very nauseogenic environment when launched in even moderate seas. The human factors associated with an abandonment of an offshore installation may significantly potentiate the existing likelihood of motion sickness. The role of the psychogenic stimuli in the aetiology of motion sickness may become more prominent in a real-life scenario when compared to a training drill.

Motion sickness questionnaires were completed by trainees (n = 899) undergoing offshore survival training and survivors (n = 39) of the 'Ocean Odyssey' drilling rig evacuation. The questionnaires provided data including incidence of vomiting, feelings of illness, reasons for illness, age, travel history, and sea conditions. In order to obtain a realistic comparison group for the survivors data, a sub-group of trainees (n = 72) was selected which had been in the same type of survival craft (Watercraft Mk H) and the same sea state (Beaufort State 4) as that of the 'Ocean Odyssey' abandonment. Significantly higher levels of vomiting and feelings of illness were recorded for the survivors than the trainees. Reasons for illness differed between the groups with the survivors implicating psychogenic factors as the main cause. Both groups revealed that vomiting took place within 1 hour. Data from the overall group of trainees showed an illness rating of 1.32 which is high in comparison to other forms of sea transportation.

The combination of the psychogenic factors and the immediacy of the onset of motion sickness symptoms and the endpoint of vomiting may have implications for preventive measures such as training and drug administration.
Strategies for the Improvement of Quality of Life and Service at the Wellsite
Authors: Lombardo G. J. , McCants K. J. , Klein M.
Published: December 2007

The oil industry, particularly exploration and production drilling has always had to contend with a remarkable set of conditions: complicated logistics, remote locations, twentyfour hour daily operations, and long and uneven schedules, to mention only a few.

Invariably, operations personnel, particularly service company personnel, are required to perform highly technical, often critical tasks for long periods of time without the benefit of sustained periods of restfulness. This condition is compounded by irregular days-off schedules and the offshore environment itself.

Research in other industries has shown that scheduling conditions similar to those experienced in the E&P drilling industry have lowered the standard of life, general health, safety and performance of employees.

With the move towards higher technology and even more critical tasks, more demanding employees and an essentially unchanged working environment, the problems are compounded even further. Work related stress and quality of life have become important factors in our employees’ career decisions and their ability to work safety.

'Ibis paper discusses the evaluation of the work schedule and work/living conditions of the wellsite measurement and services personnel of Anadrill Schlumberger, and concludes with methods to improve the safety, health and general quality of life of those personnel and the service quality they can deliver.
An Effective Corporate Drug and Alcohol Program
Authors: Wong J. , Barnes L. B. , Collins K. R.
Published: December 2007

This paper presents the policies and practice of a corporation and its operating companies in controlling workplace drug and alcohol abuse. Anonymous drug testing of representative sample groups of employees and new hires found alarming rates of drug abuse. In response, policies were updated to cover pre-employment, for cause, and other testing, searches, contractor procedures, rehabilitation, and discipline.

Step-wise implementation, a revised medical benefit package, and the expanded role of the Employee Assistance Program (EAP) — keys to maximizing employee acceptance — are detailed. Encouraging improvement in the retention rate for employees who have completed rehabilitation is reported.
Application of TRIPOD To Measure Latent Errors in North Sea Gas Platforms: Validity of Failure State Profiles
Authors: Hudson P. T. W. , Groeneweg J. , Reason J. T. , Wagenaar W. A. , van der Meeren R. J. W. , Visser J. P.
Published: December 2007

TRIPOD is a new approach to safety which stresses the importance of underlying factors in the causation of accidents. A diagnostic instrument, the Failure State Profile, has been developed using checklists of concrete indicators related to a specific set of General Failure Types identified as underlying accidents in exploration and production activities. The predictive validity of such a profile can be checked against analyses of actual accidents to see if the same pattern of underlying causes is revealed. This paper shows that the checklist-based Failure State Profile is a good predictor and can be used to help managers set priorities and allocate resources in order to optimise safety.
Retrospective Field Research of Accident and Illness Data on the Dutch Continental Shelf
Authors: Harderwijk E. P.
Published: December 2007

KIM Offshore Medical Services (OMS) provides medical back-up services for all operators in the offshore industry on the Dutch Continental Shelf.

This paper describes a retrospective study on all radio medical advice given by OMS, during a one-yearperiod. Points of interest are: frequency-distribution of illnesses and accidents; relations between illness- and accident-rates versus platformtype and function of employee; predictability of illnesses through medical examinations. Results are discussed: eye injuries are the most frequent accidents and dental problems one of the most frequent illnesses. Recommendations are given for preventive measurements in both cases.
The Modeling of Gas Explosions and the Response of Topside Structures
Authors: Scheier E. A. , Salter H. S. , Valdivieso J. B. , Wood B. J.
Published: December 2007

This paper presents a methodology to assess both the pressure impulse from a gas explosion in a semiconfined structure and the subsequent response of the structure to the imposed loads.

Analytic fluid dynamic explosion modeling methods for semiconfined structures are described. An iterative approach to developing the pressure impulse for the structure is presented. The method uses a series of intermediate structural response and explosion simulations to produce a pressure impulse which is characteristic of the explosion scenario examined.

The structural response analysis emphasizes estimating maximum response, permanent deformations, and post-explosion stability. An elasto-plastic model is used in the structural analysis to account for nonlinear structural behavior and dynamic response. It considers strain rate effects and statistical bias between minimum and actual yield stress values.

The method provides engineers with a tool which, if used in the design or refurbishment of topsides, can significantly enhance their blast resistance characteristics.
Goal-Setting Design for Fire and Gas Detection Systems
Authors: Bonn R. J. C.
Published: December 2007

In recent years the complexity and cost of Fire and Gas detection systems have increased rapidly with no measurable reduction in fatality rates or other losses. A principal reason for this disappointing outcome despite substantial investment is that systems designs have lost the focus of what they are trying to achieve.

Another reason worth exploring is that investment in other areas may result in greater benefits. For instance, diverting funds to preventing lifting accidents, helicopter failures and materials handling incidents, could result in greater OVERALL benefit since these account for a larger proportion of risks.

Nevertheless, Fire and Gas detections systems have a major role to play in preventing escalation, and this paper shows how they can be made more efficient in both cost and performance by combining four methods: targeting perceived hazards,integration from concept stage with other safety designs,control of design with effective performance specification, andcontrol of modifications throughout the system's life.
Helicopter Safety Study
Authors: Ulleberge T. , Ingstad O. , Rosness R. , Sten T.
Published: December 2007

This paper describes the HelicopterSafety Study, a research projectcarried out for A/S Norske Shell and Statoil to provide a decision basisfor future helicopter safety research and development. The study concluded that North Sea helicopter transportation has a fatal accidentrate which is about ten times higherthan that of scheduled airline services, in spite of a generally highstandard of operations, maintenanceand management. A reduction in fatalities of approximately 40%may be achieved over the next 10-15years, through extensive efforts inresearch and development. Although other sources have indicatedthat humanfactors are the dominating concern in worldwide helicopter safety,thisstudy shows that technical reliability is the most promising areafor improving safety in North Sea helicopter transportation.
Corridors Through Wetland: Impacts on Plant and Avian Diversity
Authors: Zimmerman R. E. , Isaacson H. R. , Johnson D. O.
Published: December 2007

This paper assesses the impacts of a 20-year-old pipeline right-of-way (ROW) through a boreal forest wetland. The study showed: (1) adjacent natural wetland areas were not altered in type; (2) water sheet flow restriction has been reversed by nature; (3) no non-native plant species have invaded natural areas; (4) three-quarters of the ROW area is a wedand, (5) the ROW has increased biodiversity; and (6) public access has a detrimental effect.
An Oil Spill Fate Model Including Sinking Effect
Authors: Villoria C. M. , Anselmi A. E. , García F. R.
Published: December 2007

An oil spill model, which accounts for the sinking effect, was developed. The main processes that affect the fate of oil released into the environment, for the first days of the spill, are included. These are evaporation, spreading, dispersion, emulsification and sinking. Special consideration is given to the process of sinking of oil, and the conditions at which this to occurs are described. Also, the basic equations for determining the breaking of the spill in fragments, the size of this fragments, the overwash depth, the maximum sinking depth and the distribution of oil in the water column are given. The model is applied t.o two hypothetical spills of 1000 m3 in stratified waters. The two spills differ in the density of the oil, 900 and 990 Kg/m3. In the first case the oil disappears from the surface after seven days at sea, mostly from evaporation and dispersion, while in the second case, because the high density of the oil, the spill sinks completely after 18 hours at sea.
GRI's Devonian Shales Research Program: A Progress Report
Authors: Lancaster D. E. , Guidry F. K. , Lowry P. H. , Graham R. L. , Hill D. G.
Published: December 2007

This paper presents a summary of the key observations and conclusions from the Gas Research Institute's (GRI's) Comprehensive Study Well (CSW) research program conducted in the Devonian Shales of the Appalachian Basin. Initiated in 1987, the CSW program was a series of highly instrumented study wells drilled in cooperation with industry partners. Seven wells were drilled as part of the program. Extensive data sets were collected and special experiments were run on the CSW's in addition to the operator's normal operations, with the objectives of identifying geologic production controls, refining formation evaluation tools, and improving reservoir description and stimulation practices in the Devonian Shales.

This paper highlights the key results from the research conducted in the CSW program in the areas of geologic production controls, formation evaluation, stimulation and reservoir engineering, and field operations. The development of geologic, log analysis, and reservoir models for the Shales from the data gathered and analyzed during the research is discussed. In addition, on the basis of what was learned in the CSW program, GRI's plans for new research in the Devonian Shales are described.
A Ratio-Based Epithermal Neutron Porosity for Air-Filled Boreholes
Authors: Galford J. E. , Nelson R. F. , McKeon D. C.
Published: December 2007

Sidewall neutron tools have been the standard neutron porosity tool in air-filled boreholes for 25 years. The introduction of combinable neutron tools with simultaneous dual-detector thermal and epithermal neutron measurements provided the possibility for improved porosity evaluations in both air- and liquid-filled boreholes. Obtaining thermal neutron porosity measurement in air-filled boreholes is impractical because of poor porosity sensitivity and the combined effects of borehole size and thermal neutron absorption. In contrast, the epithermal ratio possesses good sensitivity in the low-to-medium porosity range encountered in air-drilled formations. A significant, but manageable borehole size effect also influences the epithermal ratio. In addition, the epithermal ratio porosity has better statistical precision than sidewall measurements because a stronger neutron source is used with the dual-detector design.

New responses for the dual-detector epithermal neutron measurement in air-filled boreholes have been developed from data obtained in recent laboratory experiments and Monte Carlo modeling calculations. A data base consisting of 47 laboratory measurements and 164 Monte Carlo simulations was used to derive basic responses to the three principal formation matrix materials and to define a correction for variations in borehole diameter ranging from 4 to 14 in. [10 to 36 cm]. In addition, Monte Carlo simulations and laboratory experiments were used to investigate the effects caused by tool standoff.

In the past, parameterizations of the dual-detector epithermal response in air-filled boreholes were obtained through empirical relationships with measurements in liquid-filled boreholes and comparisons with sidewall neutron measurements in air-filled boreholes. Because the previous relationships were "calibrated" to other measurements made under specific borehole conditions, the new algorithms significantly improve the accuracy of the porosity determination in air-filled boreholes over a greater range of porosity, lithology and borehole diameters.

Example logs from different areas of the country are presented to demonstrate the effectiveness of the new algorithms and the improvement in statistical precision. A new porosity crossplot chart is included to estimate gas saturation and determine porosity in air-filled boreholes.
Fracturing Net Pressure Analysis for Variable-Rate Injection
Authors: Poulsen D. K.
Published: December 2007

Using various graphical techniques to observe net fracturing pressure behavior can be invaluable in diagnosing fracture growth behavior, often providing the engineer with information that allows him to take corrective action as the treatment is proceeding. Techniques previously presented for plotting net pressures and methods for interpreting the plots were developed under the implicit assumption of constant injection rate. New, more general graphing techniques are shown to be less affected by variations in injection rate, extending net pressure analysis to a wider variety of situations.
Systematic and Simple Data Collection Program Improves Hydraulic Fracturing
Authors: Plahn S. V. , Schoch F. D. , Ayoub J. A. , Holms B. A.
Published: December 2007

The majority of fracturing treatments are designed from uncertain input data. Improvements in future treatments are slow or nonexistent when little is done to decrease these uncertainties. This paper demonstrates how a modest data collection program has led to improved hydraulic fracture design in a low permeability oil reservoir. The objectives of this program were to gather data that would lead to more effective fracturing treatments and to do so in a cost effective manner.
Simulation of Particle Movement in Porous Rock
Authors: Meloy T. P. , Rülke A. W. , Williams M. , Aminian K.
Published: December 2007

A significant portion of oil remains in a reservoir after primary and secondary recovery. An understanding of the mechanisms and flow paths of fluids in permeable rock is important if greater recovery is to be realized from the reservoirs. The permeability of the reservoir rocks is not predictable from first principles. In this paper, a simple model that approximates a porous medium as a network of interconnected pores has been developed. This paper relates the use of the model to characterize fluid flow through a complex porous medium. The model consists of a regular matrix of pores that are connected by different-sized connections between the pores or, more precisely, ostioles. Because the pores are assumed to be considerably larger in size than the ostioles, all flow resistance lies in the ostioles. Hagen-Poiseuille's equation was used to give the relation between ostiole size and conductivity. Several different ostiole size distributions were studied in conjunction with Monte-Carlo simulation which assigned a size to each ostiole. The model has been used to evaluate the complexity of flow paths and the effect of mono-sized particle movement in the porous media. The particles plug the ostioles and reduce the permeability. This permeability reduction has been determined as a function of the number and size of the particles. In addition, a percolation threshold for complete flow blockage in the porous media was determined. A series of permeability reduction curves was calculated for different particle sizes for the ostiole size distributions. The shape of the permeability reduction curves provided information about the intrinsic ostiole size distribution. An experimental procedure has been proposed for determination of ostiole size distributions based on the reduction of flow rate with mono-sized particles.
Improved Model for Predicting Multiple Hydraulic Fracture Propagation from a Horizontal Well
Authors: Siriwardane H. J. , Layne A. W.
Published: December 2007

The goal of this research effort was to develop and evaluate the applicability of a simplified multicrack, hydraulic fracture model for predicting multiple fracture propagation during stimulation of a horizontal wellbore in a naturally fracture formation. This model is based on the assumption that individual fracture propagation is governed by the theory presented by Geerstma and DeKlerk2 for single vertical fractures of a constant height. In this model, the fluid flow in the wellbore is coupled with the flow in, and propagation of, multiple fractures. The fluid volumetric flow rates and pressure compatibility is maintained between the wellbore and the fracture network with a systematic iterative, numerical scheme. Prior to analysis of available field data, the model was evaluated by predicting how variations of hydraulic fracture treatment parameters Influence the propagation of a multiple fracture system. Based on these evaluations, it was concluded that both turbulent and laminar conditions of flow exist in different segments of the wellbore. It was also concluded that fracture inclination to the well-bore and entry losses into the natural fractures from the wellbore have a significant influence on the propagation of a multiple fracture system. Following this initial evaluation, data gathered from a recently completed horizontal wellbore field test were then used to evaluate the predictive capability of the multicrack hydraulic fracture model. In this field test, radioactive-tracer with spectral gamma ray logging was used to determine the locations of fractures accepting fluids and the volumes of fluids entering natural fractures. The predicted and log-derived fluid flow rates into each natural fracture were in good agreement. To date, the model has been modified to predict hydraulic fracture propagation with proppant laden fluids. Predictions from this enhanced model are being compared against available field data to evaluate the modified multicrack model. As more field data are gathered, and the multiple fracture model is modified and improved, additional comparisons can be made. The multicrack model provides further insight into the factors that govern multiple fracture propagation in horizontal wells.
Determinants Of The Potential Supply Of Natural Gas
Authors: Beebe B.W.
Published: December 2007

American Institute of Mining, Metallurgical, and Petroleum Engineers, Inc.

This paper was prepared for the Regional Gas Technology Symposium of the Society of Petroleum Engineers of AIME, to be held in Omaha, Neb., Sept. 12–13, 1968. Permission to copy is restricted to an abstract of not more than 300 words. Illustrations may not be copied. The abstract should contain conspicuous acknowledgment of where and by whom the paper is presented. Publication elsewhere after publication in the JOURNAL OF PETROLEUM TECHNOLOGY or the SOCIETY OF publication in the JOURNAL OF PETROLEUM TECHNOLOGY or the SOCIETY OF PETROLEUM ENGINEERS JOURNAL is usually granted upon request to the PETROLEUM ENGINEERS JOURNAL is usually granted upon request to the Editor of the appropriate journal provided agreement to give proper credit is made.

Discussion of this paper is invited. Three copies of any discussion should be sent to the Society of Petroleum Engineers office. Such discussion may be presented at the above meeting and, with the paper, may be considered for publication in one of the two SPE magazines.

A number of predictions of need for a substantial increase in the supply of natural gas by 1980 inevitably lead to consideration of the basic determinants of available future supply. The Potential Gas Committee considers broad economic and technologic determinants in its definition of potential supply. Its estimate is based on a fair but reasonable price and normal improvements in technology. The ability of natural gas to compete with other forms of energy at the market place is therefore one of the ultimate determinants of the potential supply of natural gas. Another is the producers' willingness to enter into the producers' willingness to enter into the hazardous search for and development of sufficient gas supply at prevailing costs and wellhead prices. Hence the estimate is elastic and subject to revision as determinants change. Other factors, although exerting influence on the potential supply, are more important potential supply, are more important in determining rate at which new supply is made available.

According to the Potential Gas Committee's estimates, the potential supply of natural gas should not cause concern from 1968–80. The Committee makes no predictions in regard to the rate at which the potential supply will be developed and produced, perhaps the most important factor. The annual average rate of additions to new supply has been only 19.7 Tcf for the past 12 years. There seems to be no compelling reason for its increase. An increase to an average of at least 23 Tcf per year is necessary simply to supply forecasted need for at least 300 Tcf during the period. And this quantity only meets increasing requirements. If a reserve life index of 15 years is to be maintained, the rate must be considerably higher.
Slick Trajectory Predictions for the Arabian Sea
Authors: Kurup P. G.
Published: December 2007

The environmental damage caused by slicks at sea and the subsequentdeposition of tar on shores is wellknown. Contingent planning forsuccessful deployment of men and material for slick combatment programmes requires knowledgeof calculated positions of the slick at anyinstant oftime after the spill has occurred. The paper presents slick drift vectors for the Arabian Sea for every 2° lat. x 2° long, grids, calculated from monthly wind andcurrent data obtainedfrom the KNMIAtlas. Monthly charts have been produced to givethe resultant drift trajectories of slicks from 61 hypothetical spills occurring in the vicinity of the shores of the Arabian Sea on thefirst day of every month. The location of possible slick deposition on the shore and the duration available for weathering have been predicted. Of 732 hypothetical spills studied, 135 may pollute the Indian coast with varying intensity.The period May-September provides more chances of severe oil deposition on the west coast of India while the period October-February may be critical for the western shoresof the Arabian Sea. The drift velocities have highest magnitudes during July. Slicks from the farthermost spill considered (370 kmoffshore) takes only 14 days to reach the Indian shore during July. Spills occurringduring December in the western Arabian Sea will affect the shores of Africa and Arabia severely.
Occupational Stress and Accidents Offshore
Authors: Sutherland V. J.
Published: December 2007

Stress, personality and accident involvement were assessed in one-year study of offshore personnel. Results indicate response to stress relates to occupational status, installation type, location and size. Accident involvement has an adverse impact on the longterm wellbeing of the individual. Personality mediates in the stress-accident process. Certain styles of behaviour are associated with increased accident involvement and poor wellbeing. It is recommended that more attention is paid to human-factors assessment offshore.
Review of the Geological Environment for Horizontal Wells
Authors: West C. C. , Bodnar D. H.
Published: December 2007

The geological aspects of drilling horizontal wells in various geologic environments worldwide are reviewed. Predominantly development wells, they are often drilled in locations where a conventional well would not achieve the same geological and subsequently economic, objectives. This paper summarizes recent activity and demonstrates that geologic conditions play a large part in determining the success or failure of a horizontal drilling project. The examples cited in this paper are all taken from previously published literature and include horizontal drilling projects in the USA, United Kingdom, Norway, Italy, The Netherlands and Denmark.

This paper concludes that a large range of geological conditions have been tested by horizontal drilling with varying degrees of success, the results of which might prove helpful in assessing future prospects for horizontal wells.
Dynamic Etching Tests And Their Use In Planning Acid Treatments
Authors: Broaddus G.C. , Knox J.A. , Fredrickson S.E.
Published: December 2007

American Institute of Mining, Metallurgical, and Petroleum Engineers, Inc.

This paper was prepared for Oklahoma Regional Meeting of the Society of Petroleum Engineers of AIME, to be held in Stillwater, Okla., Oct. 25, 1968. Permission to copy is restricted to an abstract of not more than 300 words. Illustrations may not be copied. The abstract should contain conspicuous acknowledgment of where and by whom the paper is presented. Publication elsewhere after publication in the JOURNAL paper is presented. Publication elsewhere after publication in the JOURNAL OF PETROLEUM TECHNOLOGY or the SOCIETY OF PETROLEUM ENGINEERS JOURNAL is usually granted upon request to the Editor of the appropriate journal provided agreement to give proper credit is made. provided agreement to give proper credit is made. Discussion of this paper is invited. Three copies of any discussion should be sent to the Society of Petroleum Engineers office. Such discussion may be presented at the above meeting and, with the paper, may be considered for publication in one of the two SPE magazines.

The satisfactory stimulation of oil and gas producing wells by "Fracture Acidizing" is dependent upon development of adequate flow capacity in naturally occurring or induced fractures of sufficient areal extent.

The flow capacity is either obtained or improved through the action of the acid on the exposed fracture faces. The type and quantity of acid used in a treatment greatly influences the pattern and degree of etching. Consequently, the type of etch affects the fracture flow capacity.

Dynamic acid etching tests can be used to determine the feasibility of an acid treatment, and the type acid and the contact time necessary to produce a conductive fracture. produce a conductive fracture

Introduction

The first wells stimulated with hydrochloric acid were treated by dumping small quantities of acid down the well. These treatments were interstitial and improved the natural permeability near the well bore only. Later, when acid inhibitors were developed and pumping equipment was improved, acid was pumping equipment was improved, acid was injected at higher rates and pressures, and consequently larger volumes were used. At this time, acid reaction time, fluid efficiency and pump rate were used in designing acid stimulation treatments. For years, these factors were used, and are still being used, to calculate the surface area of created fractures. It was assumed that a conductive fracture would be created by hydrochloric acid in limestone and dolomite formations. Of course, this is not always true.
Fracture Identification and Quantification Using Borehole Images: Maracaibo Basin, Venezuela
Authors: Lambertini R.
Published: December 2007

Borehole images obtained with the Formation MicrScanner Tool (FMS) have added a new dimension to reservoir description and characterization. As confidence in fracture detection and analysis grows in the petroleum industry, more emphasis is been placed on the modeling of fracture distribution within the reservoir.

The FMS logs that have been run in several wells in the Maracaibo Basin (Tretiary and Cretaceous Formations) have been used with cores, open hole logs and conventional dipmeter in an integrated approach to reservoir description.

To assist in the interpretation and quantification of fractures, especialized image analysis have been developed. Borehole imagery records fracture orientation and allows natural or induced fractures to be distinguished. Quantitative analysis of fracture revealed with the FMS images has been greatly advenced with the development of the FRACVIEW software.

During FRACVIEW analysis, different kinds of fractures are grouped into statistical or geological sets using the Image Examiner Workstation (FLIP) according to fracture density, lenght, width and porosity.

Such information is proving to be a valuable guide to the positioning, testing and completion of new wells.
Conduction Calorimetry Technique in Cement Hydration for Oil Wells
Authors: Santos F. P. , Campos W.
Published: December 2007

Conduction calorimetry technique makes possible to follow the kinetic of cement hydration through the rate of heat evolution. This work presents experimental results using the following types of cement: oilwell Class G, Class A, Pozzolanic and Blast Furnace. The effects of cement aeration (carbonating and/or humidifying), temperature and use of additives on the hydration rate of Class G cement slurries were analysed. In addition, the characterization of the different cement types was performed. The tests were run in a JAF Conduction Calorimeter which working principles were described in the work. A computer program was developed to calculate the heat liberation rate and the cumulative heat of hydration generated along the process.
A New Method to Estimate Compressibility Factors for CO2 Hydrocarbon Mixtures
Authors: Rojas G. , Requena O.
Published: December 2007

This work shows experimental values of compressibility factors for CO2 – hydrocarbon mixtures in different proportions. The measurements were done in a Ruska supercompressibility cell varying the pressure (200 – 2500 psia), the temperature (100 – 200°F) and the molar percentage of CO2 (85 – 100%). With the experimental data, generalized Z (CO2 – Hydrocarbons) were plotted as a function of Psr (pseudo reduced pressure) and Tsr (pseudo reduced temperature).

The equation state of Peng-Robinson (EOS-PR), Starling (EOS-S) and Redlich - Kwong - Soave (EOS-RKS) were tested to simulate the experimental data, and it was found that the EOS-S and EOS-PR are the ones that predict the mixtures compressibility factors studied with greater precision.
Resistance of Module Structures to Blast and Fire Loading
Authors: Snell R. O. , Corr R. B.
Published: December 2007

During the course of a blast incident a module structure and plant will be required to withstand blast overpressure, drag loading, and possibly projectile impact. A fire may subsequently occur adding load to a potentially blast damaged structure.

In response to the Cullen Enquiry into the Piper Alpha incident in the North sea the authors developed a structural design philosophy for application to new designs and the assessment of existing platforms. Although primarily developed for offshore structures it is also applicable to onshore plant.

This paper outlines a design philosophy for blast overpressure, drag and fire loading. Potential projectile impact energy design criteria and the results of some impact tests on typical materials are described.
Layered Reservoir Evaluation Using Pressure and Flow Rate Transient Analysis
Authors: Cabrera J. , Silva R. , Ramones M. , Mendoza L. , Prat G. Da
Published: December 2007

In this work mathematical concepts and fundamentals of a model for well testing evaluation of layered reservoirs are presented. The model, based on that developed by Eligh-Economides et al1 considers the production to the well as coming from several layers. These layers may be different, regarding lithology and fluid properties. The solutions allow the calculation of the flowing pressure, average pressure, skin and flow rate for each individual layer. This is important for pressure transient analysis since the conventional methods only provide the global pressure for all the layers. Crossflow is included in the model. The solutions with model proposed are compared with those given by a numerical simulator in order to check the validity and are in excellent agreement with the numerical simulator. Several field examples are presented to show model applications.

Individual layer evaluation can be obtained when testing a well completed in several layers by the model presented. Also, production decline monitoring is possible for each layer.