bluuebunny/crossref_metadata_2025 huggingface dataset:
Hydraulic Workover Techniques: Their Versatility and Applications
Authors: Maddox S. D.
Published: December 2007

The increased impetus on economic efficiency and safety in oil and gas service operations has challenged the industry to seek newer and better strategies that are able to comply with current operational needs. In response to these challenges, state-of-the-art hydraulic workover (HWO) equipment and systems, which can provide alternative methods to traditional drilling and workover operations and can comply with economic and safety constraints, have now been developed. These new systems not only enhance problem-solving options but also increase protection of service personnel and the environment.

This paper will discuss the broader range of applications that has emerged as a result of improvements in HWO technology, the history of these systems, new HWO capabilities, components of the new systems, and safety enhancements recently introduced to the industry. Case histories will provide supporting data.
Scale Prediction, Measurement, and Control in a Subsea Satellite Field
Authors: Wright R. J. , Hall J. R. F. , Mcintosh C. J.
Published: December 2007

Predictions and workover findings revealed that sulphate and carbonate scale problems have a significant impact ·on the Glamis field production. Scale predictions closely agreed with the findings. An estimation of the rate factors governing the kinetics of calcium carbonate have been made. Specific treatment facilities, permitting downhole injection and inhibitor squeezing were incorporated into the designs of the recompleted satellite wells to combat the two scaling mechanisms.
Implementation of Innovative Operating Systems in the Forties Field
Authors: Murray Philip , Dixon G. T. , Thomson R. L.
Published: December 2007

With the drive to constantly improve safety and to operate plant more efficiently, new initiatives like Empowerment, Total Quality Management and Total Productive Maintenance, are beginning to be adopted in North Sea operations. A pre-requisite to these new approaches is to be able to both provide operational staff with all the information they require to run the plant safely and efficiently, and equally importantly provide a mechanism for everyone to share knowledge and build on their combined experience. Traditional paper based information systems have failed to deliver the performance required in this new environment. This paper describes how a new and innovative computer based system was developed in conjunction with front line operational staff. The system allows staff at all levels and in different disciplines, to access information from the many islands of data associated with offshore facilities. Simple point and click techniques allow staff to access and annotate different data formats including engineering drawings, sound commentary, procedures and photographs.
Geometric Factors for Probe Permeameter Measurements on Heterogeneous Rocks
Authors: Manrique J. F. , Kasap Ekrem , Georgi D. T.
Published: December 2007

Probe permeameters are preferred for making fast, high density and non-destructive permeability measurements on relatively smooth rock surfaces. Probe measurements can be conducted with both steady-state and unsteady-state flows. The technique relies on geometric factors to account for highly non-linear hemispherical llow. Previous studies have presented geometric factors for homogeneous porous media. Naturally occurring porous media are rarely homogeneous. Some heterogeneities are natural, others are created during drilling (formation damage) and some during subsequent core handling (slabbing). Unfortunately, our ability to deal analytically with heterogeneity is limited. Thus, it is necessary to use numerical methods to derive geometric factors for these complex, but realistic situations.

A finite element simulator was used to study effects of heterogeneity on probe permeability measurements and the differences between the geometric factors for steady and unsteady state Hows. Simulation results show that geometric factors for unsteady-state Hows are almost identical to the ones obtained for steady-state. P.fleets of a nearby llow barrier on a probe measurement are studied experimentally and numerically. Results are compared, and an excellent match is observed. Prom llow barrier studies, we concluded that the effect of a local flow' barrier is unimportant when the barrier is located farther than one-half of the probe-tip diameter from the probe.

Probe measured permeability on a damaged formation is profoundly affected by the damage zone thickness. Working with geometric factors for measurements on damaged zone, we developed a methodology to obtain undamaged and damaged zone permeabilities, and damage thickness. To obtain such information three measurements with three different probe tip sizes are required.
Technical Factors Useful for Screening Carbonate Reservoirs for Waterflood Infill Drilling
Authors: Lu Guo Fan , Jagoe B. K. , Wu C. H.
Published: December 2007

This paper presents technical factors useful for screening Permian Basin carbonate reservoirs for waterflood infill drilling. These factors are identified from the technical and economic evaluation of twenty-one San Andres carbonate units. The technical evaluation analyzes the primary, initial waterflood and infill drilling oil recoveries. The economic evaluation considers only the ultimate incremental oil production from infill drilling.

The technical factors are (1) the oil-in-place per well estimated at the start of infill drilling, (2) average annual rate of incremental oil production from infill drilling, (3) the well spacing reduction, (4) the net thickness, and (5) the depth of reservoir.
Interpretation of Field Pressure and Production Data with a New Analytical Layered Reservoir Simulator
Authors: Gao Chao , Jochen J. E. , Lee W. J.
Published: December 2007

This paper presents the application of a new analytical simulator specifically developed for multilayer reservoirs. In this paper, we demonstrate how this analytical simulator can be used, the same way as a conventional numerical simulator, to history-match field pressure data, production data, and forecast reservoir performance. Two field cases are presented in which analytical simulation results and numerical simulation results are compared.
The New, Generalized Material Balance as an Equation of a Straight Line: Part 1 – Applications to Undersaturated, Volumetric Reservoirs
Authors: Walsh M. P. , Ansah Joseph , Raghavan Rajagopoal
Published: December 2007

This work presents a general, straight-line method to estimate the original oil and gas in-place in a reservoir without restrictions on fluid composition. All past efforts are applicable to only restricted ranges of reservoir fluids. Our work supersedes these and is the first to be applicable to the full range of reservoir fluids—including volatile-oils and gas-condensates. Our work is based on the new generalized material-balance equation recently introduced by Walsh.1 The superiority of the new method is illustrated by showing the error incurred by preexisting calculation methods. Guidelines are offered to help identify when preexisting calculation methods must be abandoned and when the new methods featured herein must be employed. The results of our work are summarized in a set of companion papers. Part 1 discusses applications to initially-undersaturated, volumetric reservoirs and Part 2 discusses applications to initially-saturated and non-volumetric reservoirs.
New Advanced Solids/Oil/Water Separator
Authors: Woinsky S. G.
Published: December 2007

ACS Industries, Inc. recently commercialized proprietary advanced oil/water separation technology which separates heavy oils (up to 50,000 centistokes). The separation efficiency of these units is exceptional (down to less than 2 PPM oil in water in field trials). During emergency situations, they can produce effluent water containing less than 15 ppm of oil (with up to 50% oil in the feed).

The system is commercially proven with 32 units built for the Marine Spill Response Corporation (MSRC), plus units processing waste water at 3 power plants. These units are mounted on a single skid in capacities up to 525 GPM, and they are fully automated.

ACS has also been providing CPI separators to the Process Industries for seven years. We are now integrating our CPI separator know-how with our proprietary oil/water separation technology to provide higher quality water effluents at lower cost than can be achieved by any other technology.

The design concepts, commercial test data, a summary of the factors affecting the extent of separation and a competitive comparison are included in Tables 1 through 3 and Figures 1 and 2. More detailed information (including the history of the development, design details and costs) is available in copies of a presentation given previously to the M. W. Kellogg Company. Also, samples of chevron, sheet metal structured packing and fiberglass/wire co-knit internals are available for examination.

The inventions in this development include the use of a hydrocarbon solvent to cut viscosity and keep the high surface area (4,000 to 5,000 sq ft/cu ft) separation media clean, pulling fluids through the system rather than pumping through to avoid shearing oil to fine drop size, the development of a serrated edged capacitance probe to be able to detect the viscous oil/water interface properly, the use of proprietary high surface area separation media and the development of a highly sophisticated and redundant control system to allow for operation unattended or by nontechnical personnel.
New Source Air Pollution Permits in Texas and New Mexico
Authors: Hofmann J. E. , Fusselman D. K. , Liles R. J.
Published: December 2007

New source air permitting of oil and gas processing equipment ranges from fairly simple procedures under the Texas Natural Resource Conservation Commission (TNRCC) standard exemption list and the New Mexico Environment Department (NMED) registration regulations to an extremely complicated procedure requiring a federal Prevention of Significant Deterioration (PSD) and/or non-attainment review. The following topics relating to obtaining air pollution construction permits for processing equipment will be addressed in this paper: Type of permit/exemption/registration necessary for constructionSpecific permit/exemption/registration requirementsNew Source Performance Standards (NSPS) Subparts KICK, LLL, GG, K, Ka, and Kb

Concepts outlined in this paper pertain to air pollution New Source Review (NSR). Owners and operators of oil and gas processing and production facilities that propose new or modified facilities should be aware of the regulations and interpretations contained in this paper.

The primary effects of the 1990 Clean Air Act amendments on NSR requirements are identified.
Improved Well Design Maximises Oil-Rim Profitability
Authors: Pelgrom J. J. , Mann J. P. , Davidson C. J. , Tickle A. J. , Blok R. H. , Mattjes G. R. , Risseeuw A. S.
Published: December 2007

Through the application of horizontal well technology in a giant shallow, un-consolidated oil-rim reservoir, Shell Gabon significantly increased field output and recovery at reduced cost, while minimising the environmental impact of field development. Systematic well design changes were implemented particularly in completion hardware and mud- and completion fluids and latest coiled tubing-technology was introduced in efforts to improve completion efficiency.

The paper summarises the observations and practices resulting in the improved completion technology and gives examples of the production logging tool selection and interpretation techniques developed. An outline is given of techniques which require further development to control over the inflow distribution in un-consolidated oil-rim reservoirs such that the recovery of the field can be achieved with the minimum number of wells.
The New Federal OCS Regulations in the Light of Santa Barbara
Authors: Wayland Russell G.
Published: December 2007

When the first Outer Continental Shelf leases were issued in 1954, the oil industry was operating near shore in shallow waters. Although regional OCS Orders issued under the regulations have been kept reasonably up to date with advancing technology, the Secretary's regulations had not undergone a complete review by the Department and the interested public since May 1954. The Santa Barbara public since May 1954. The Santa Barbara event triggered the complete review of both the regulations and the OCS Orders.

The new regulations and orders not only reflect technological changes but also changes in public attitudes toward preservation of our environment. Of particular interest to petroleum engineers are the provisions petroleum engineers are the provisions requiring much more detailed attention by the Geological Survey to company plans and equipment for prevention of pollution and blowouts before drilling may begin from platforms or mobile rigs. This includes increased Survey attention to the estimated depths to the top of significant markers; to depths at which water, oil, gas and mineral deposits are expected; to the proposed blowout prevention, casing, mud, and cementing programs; and to chokes and similar shut-off devices in wells and pipelines.

While some call the new regulations harsh and tending to reduce exploration incentive, most industry spokesmen, we believe, find them to be a simple extension and clarification of practices that responsible oil producers have generally adhered to for producers have generally adhered to for years.

If the new regulations have much to say about preventing blowouts and spills, is there any operator who would knowingly run a chance of a blowout? The very small ratio of spills to offshore wells drilled answers the question for the most part, but the fact remains that blowouts and spills do occur, that their potential for damage is great, and that every reasonable precaution must be taken to prevent their occurrence.

The new regulations reflect the oil and gas industry's concern for conducting operations that do not interfere with the rights of others, and its responsibility for corrective action when things go wrong.
New Options To Eliminate Corrosion of Completion Equipment in Water Injection Service
Authors: Chitwood G. B. , Coyle W. R.
Published: December 2007

Evidence gathered from examination of completion equipment corroded in water injection service reveals that corrosion is strongly influenced by dissolved oxygen. Field history has shown severe corrosion of equipment made from 9Cr-1Mo and 17-4PH stainless steel. Experience suggests that while corrosion is minimized by exclusion of oxygen, the practical limitations of water treatment and surface injection facilities require a different approach. Duplex stainless steel was investigated in the laboratory and found to have promise. Subsequently, completion equipment made from this material has been put into service and is performing without failure.
Minimizing Equipment Failures in Rod-Pumped Wells
Authors: Patterson J.C. , Bucaram S.M. , Curfew J.V.
Published: December 2007

SPE Members

Equipment failure and it's attendant costs are extremely important in today's petroleum industry. Since Rod Pumping is the predominant means of artificial lift, minimizing equipment failure in rod pumped wells can have a significant impact on profitability. This paper addresses recommendations which have proven successful in the majority of wells. These have been developed within ARCO over the past 25 years and include equipment selection and design, operation and chemical treatment. The ultimate goal is to address and solve problems on a well by well basis.

Introduction

In Rod Pumping installations, premature equipment failures are usually the result of one or more of the following causes:Design deficiencies* Improper selection of material (Material deficiencies)Manufacturing deficienciesErrors in assemblyService conditions which were not considered in design

Failure control in it's simplest form is failure analysis with the goal of achieving corrective action. This paper is a compilation of recommendations which have been learned from field locations throughout the United States and Foreign locations.Data - Minimizing equipment failures requires a tracking system that identifies the failures by type (rod, tubing, pump, etc.), location (pin, body, barrel, plunger, etc.) and cause (abrasion, stuck, corrosion, split, plugged, etc.). With this data base the failures can be trended indicating the overall performance with time. Trending helps provide for comparison between producing areas.

P. 95^
Service Companies' Perspective of Strategie Alliancing in Alaska
Authors: Barnette J. C. , Spearman J. W.
Published: December 2007

The well servicing alliances between BP Exploration (Alaska) and several nonaligned service companies are now in place and thriving from both the operator's and the service companies' perspectives.

Although these successful alliances were formed for the same reason as with most working alliances (e.g., maximum value), the development of these working relationships was radically different. Independent alliances were implemented rather than a single alliance with numerous aligned service companies. This paper will detail the procedures taken to form and maintain these alliances.

Some items of interest to be discussed include:

Past operations — previously driven by bidding; however, under these alliances, maximum value and quality are the driving forces. Conflicting goals — realigned from the traditional relationship to a partnership where both operating and service companies work out issues together. Traditional "sales" — refocused to concentrate on service, job planning, and communication, which allows the service company to provide input in all stages of the operation. Accounting practices — streamlined and simplified with invoicing being changed from daily, or per job, to monthly. Pricing structures — redesigned to provide the operating company with the flexibility to use the best service needed for the job rather than using the least expensive technique. Incentives — put in place so that safety and environmental protection are top priority. Performance incentives — put in place to ensure continuous improvement and to maintain required standards.
Cost-Effective Solutions to Well Plugging and Abandonment
Authors: Smith M. V. , Pitura J. M.
Published: December 2007

Plugging and abandoning wells and squeeze cementing zones in wells have become increasingly more expensive and labor intensive. Recently, however, two cost effective methods have been developed for "one-trip" setting of both bridge plugs and cement retainers, eliminating the need for extra contractors and equipment, and reducing job time considerably. In some instances, the contract service rig can also be eliminated.
Coiled-Tubing Drilling in Kern County, California: A Case Study
Authors: Love C. L. , Eagle T. M. , Adamson Sam
Published: December 2007

Two shallow wells were successfully drilled with coiled tubing (CT) in the McKittrick Field, Kern County, California in April, 1993. These wells were the first "grass roots" wells drilled with coiled tubing in the United States and the first known wells worldwide to be drilled with medium diameter bits (6.25") which would permit completion with 5" casing1. The operator's objective of providing low cost evaluation of undeveloped stepout areas and the contractor's objective of adapting a conventional coiled tubing unit (CTU) for economic drilling or redrilling were effectively achieved. This local adaptation of coiled tubing drilling (CTD) opens the door for a series of niche applications within the general area of well drilling/completion.

This paper summarizes the case history experience of application of this new technology to the specific two well situation and defines some potential applications of the technology.
The Effective Use of Pulse Neutron Logging for Fluid Surveillance in a Low-Salinity Environment, Endicott, Alaska
Authors: Cunningham A. B. , Schnorr D. R.
Published: December 2007

The Pulse Neutron Log (PNL) is often an ineffective tool for water influx and water breakthrough surveillance when formation and injected water salinities are low. This is the case in most of the North Slope fields in Alaska. However, at Endicott, which has uniform low capture cross-section sands, the precision of the sigma measurement is sufficiently accurate to identify, and quantify, water movements behind casing. Aquifer influx as well as seasonal salinity variations of injected seawater are detectable using time lapse logging techniques. Because of tailpipe and sub-sea safety valve restrictions, the PNL was also chosen for the Endicott key well gas monitoring program. Gas cap movement and gas under running are effectively monitored using detector count-rate ratios, porosity, and Sigma measurements.

Associated PNL measurements such as Sigma borehole and inelastic count rates have been effectively used to identify casing leaks, and flowing perforations not detected with standard production logging suites. Water production and water channeling are also readily identified by logging the PNLs with the pulse neutron generator off in order to identify sources of oxygen activation. Water Flow logging, WFL*, has also provided additional ability to identify water production and channeling.

The PNL has been used effectively to monitor fluid movements within the Kekiktuk Formation. However, as the field matures, various factors lessen the utility of the PNL for fluid surveillance. Wells which were initially logged flowing must increasingly be logged shut-in due to steadily rising gas production and associated diffusion problems from gas in the wellbore.

Also, the increasing presence of barium sulfate scale, with associated high background radiation, eventually reduces the ability to make accurate measurements and interpretations across these affected portions of the wellbore.
Applied Hydraulic Fracture Modeling Improves Results, Cleveland Sand, Ochiltree County, Texas
Authors: Aud W. W. , Brady C. L. , Rainbolt M. F. , Perry K. F.
Published: December 2007

This discussion shows the positive results obtained from using state-of-the-art technologies to interpret, diagnose, and predict hydraulically fractured well characteristics and responses. Extensive reservoir and geological data were collected and integrated into both reservoir simulation of production and pressure transient responses and advanced hydraulic fracture modeling to characterize the Cleveland formation in the Ellis Ranch Field area. The results showed that vertical proppant placement was a critical issue and that by making the necessary adjustments to improve the proppant placement the fracture treatment costs could be reduced and the production results improved.
Multiphase Science and Technology for Oil/Gas Production and Transport
Authors: Oliemans R. V. A.
Published: December 2007

During the past twenty years multiphase flow technology has become increasingly important for the economic transportation of well streams from reservoir to process. In particular, production offshore, where the trend is to develop numerous small fields by transporting untreated fluids Via existing infrastructures, imposes high demands on the multiphase science and technology required to ensure economic and safe operation. This paper addresses the state of the art in the development of multiphase production systems and highlights future trends. It subsequently scrutinizes the reliability of models and techniques currently available and identifies issues in the area of multiphase flow technology that need to be addressed. Typical aspects that will be covered are steady and transient two-phase pipe flow modelling, the effect of water on oil/gas flow, multiphase metering and multiphase boosting, and the use of trunkline management systems in multiplatform production schemes.
Influence of Small-Scale Rock Laminations on Core Plug Oil/Water Relative Permeability and Capillary Pressure
Authors: Honarpour M. M. , Cullick A. S. , Saad Naji
Published: December 2007

Relative permeability is a critical parameter in reservoir engineering calculations and performance predictions using numerical simulation. Little has been published on the effect of core-scale heterogeneities on relative permeability. Small-scale rock heterogeneity can lead to directional-, length-scale dependent relative permeabilities, and distinct hysteresis characteristics.

This report presents relative permeability and capillary pressure data on a core that is characterized by millimeter-scale parallel laminated bedding. The core was characterized using petrographic analysis, CT scanning, and minipermeametry. Anisotropy of relative permeability is demonstrated by comparing relative permeability measurements on a plug drilled parallel to the laminations with those of a plug drilled normal to the laminations. Steady-state and unsteady-state oil-water relative permeability data were collected using X-ray Scanning for insitu fluid saturation measurement. Measured secondary drainage curves show distinctive characteristics when the principal flow is parallel to laminations as compared to flow normal to the laminations. Porous plate and centrifuge capillary pressure measurements illustrate differential drainage and imbibition among laminations.

These results demonstrate relative permeability anisotropy attributed to capillary pressure contrast among small-scale laminations. The directional variability is not apparent from single-phase directional permeability measurements. Core plugs with more isoptropic permeability distribution show reduced impact of small-scale heterogeneity.
Mixed Reservoir Characterization Methods
Authors: Damsleth Eivind , Holden Lars
Published: December 2007

The main objective of reservoir characterization is to describe the features which influence the amount, position, accessibility, and flow of fluids through a reservoir. These features will be: The structural aspects (depth to the reservoir boundaries and inter-reservoir surfaces), faults (both seismically identifiable and sub-seismic faults), flow-units or facies bodies (position, orientation and size), and the spatial distribution of the relevant petrophysical parameters (permeability, porosity, saturations, …) within each flow-unit. Although some "hard" data from seismic and wells will be available, there is a definite stochastic element in all these features. Stochastic techniques are thus required to model them properly.

The paper reviews a number of techniques available for stochastic modeling of the above features: (marked point processes, Markov fields, truncated Gaussian fields and indicator kriging for modeling discrete events (flow-units, faults, barriers); Gaussian fields and indicator kriging for modeling property values (depths, fault transmissibility, petrophysical variables)). The different techniques can be mixed or combined to give a complete stochastic model of every relevant aspect of the reservoir. Several examples from the North Sea will be presented.
Selection of Optimum Intermittent Lift Scheme for Gas Lift Wells
Authors: Chacín J. E.
Published: December 2007

Maracaibo Lake wells are currently producing approximately 800 mstbd of crude oil from some 7000 wells. 90% of these well are in gas lift and approximately 760 wells are being lifted intermittently. Natural reservoir decline will increase the number of wells that will require intermittent lift at an estimated rate of 150 wells per year.

Continuous research and modeling efforts have been performed over the last thirty years to understand the dominant physical characteristics and develop mechanistic computational tools for the design of the various existing intermittent lift schemes (conventional, plunger assisted, chamber lift). The present paper will review relevent published work regarding intermittent lift and describe key modeling considerations for each scheme.

Furthermore, we will focus on proper selection of intermittent lift scheme as a function productivity index, reservoir pressure, wellbore equipment and completion and other inportant well parameters.
Compositional Gradients in Petroleum Reservoirs
Authors: Whitson Curtis H. , Belery Paul
Published: December 2007

This paper describes methods for calculating the one-dimensional, vertical variation in composition with depth caused by gravity and thermal gradients. The Peng-Robinson (PR) and Soave-Redlich-Kwong (SRK) cubic equations of state (EOS) are used as thermodynamic models. Examples of calculated compositional gradients are given for reservoir fluid systems ranging from black oils to near-critical oils.

A solution algorithm is suggested for solving the isothermal gravity/chemical equilibrium (GCE) problem. The algorithm is simply an adaptation of a method proposed by Michelsen1 for calculating saturation pressure. The problem of false (unstable) solutions is discussed, and the subsequent need for applying phase stability analysis to identify such false solutions. Finally, an algorithm is given for determining the location of a gas-oil contact (GOC).

A model for treating both gravity and thermal gradient has been used to quantify the potential effect of thermal diffusion on compositional grading. The model used was proposed by Belery and da Silva2. Unfortunately, the physics and thermodynamics of thermal diffusion are not well understood. This model is only one of several approaches which have been suggested for treating thermal diffusion. Examples given in our paper show that thermal diffusion can have a marked effect on compositional grading, with the possibility of enhancing, reducing, or completely eliminating gradients caused by gravity alone.

We illustrate the potential danger of using gradient calculations for defining original hydrocarbon distributions (oil and gas in place) when limited fluid samples and PVT data are available. Furthermore, guidelines are given for when to use gradient calculations, and how to develop an EOS fluid characterization for reservoirs exhibiting compositional variation.
Predicting the effects of pore pressure penetration on the extent of wellbore instability: Application of a versatile poro-elastoplastic model
Authors: McLellan P. J. , Wang Y.
Published: December 2007

A poro-elastoplastic wellbore stability model, which accounts for the presence of an internal filter cake in a plastic yielded zone, and capillary threshold pressures has been developed for a Mohr-Coulomb, strain-weakening material. The extent of the plastic yielded zone may be predicted for steady state fluid inflow (underbalanced) or outflow (overbalanced) conditions. The model predicts that for overbalanced drilling conditions the filter cake efficiency, or its ability to reduce pore pressure penetration, can significantly affect the extent of the plastic yielded zone which can develop in a permeable formation. Example applications of the model to drilling and completing horizontal wells in a unconsolidated, bitumen-saturated sand and a weak, cemented sandstone are described.
Rock-bit wear in ultra-hot holes
Authors: Macini Paolo , Mesini Ezio
Published: December 2007

The paper presents a new model of rock-bit wear, and refers to bits utilized in ultra-hot wells drilled in the geothermal area of Larderello, Tuscany, Italy. In particular, the model, conceived from field data, indicates that the correct evaluation of rock-bit wear, considered in the light of the knowledge of drilling parameters and downhole conditions, can improve the overall drilling performances through a better interpretation of the relationships among rock-bit, formation properties and bottomhole temperature. This paper investigates the detrimental effects, not yet very well understood, of high bottom hole temperature on sealing and reservoir systems of friction bearing rock-bits. A particular bearing wear model for friction bearing rock-bits utilized in ultra-hot holes has been considered and further verified via laboratory inspections on dull bits. A novel interpretation of flat worn cutting structure has been derived from the above wear model and viable recommendations for improving the cost of drilled interval are suggested. Also, rock-bit field data from several Italian geothermal wells are reported and analized as an example of field application.
Exploiting Poroelastic Effects and Permeability Contrasts to Control Fracture Orientation
Authors: Boone Thomas J. , Wawrzynek Paul A.
Published: December 2007

This paper demonstrates how poroelastic effects, acting in combination with anisotropic permeabilities (i.e. a vertical permeability that is less than the horizontal permeability), will typically favour reorientation of a propagating fracture from vertical to horizontal. The paper includes examples of fracture reorientation using a specially adapted finite element code that can model curved fracture propagation.
Contribution of Poroelasticity to Reservoir Engineering: Lab Experiments, Application to Core Decompression and Implication in HP-HT Reservoirs Depletion
Authors: Boutéca M. J. , Bary D. , Piau J. M. , Kessler N. , Boisson M. , Fourmaintraux D.
Published: December 2007

The linear mechanics of porous rocks is summarized : basic equations – i.e. constitutive law and fluid mass balance – and most useful relationships are given. For reservoir engineering applications, the hydrostatic loading case is dealt with in detail. The conventional diffusivity equation -i.e. uncoupled pressure equation-is then derived. Experimental procedures are suggested and results obtained on outcrop and reservoir sandstones are given. The data indicate that the sandstones have a nonlinear behavior and that volumetric coefficients are functions of the difference between the confining pressure and the pore pressure. A model is then proposed based on Biot's semilinear theory. The reservoir rock behavior is shown to be in agreement with this model for the experiments performed. As an application effective stress is computed. Finally the role of pore pressure in damaging cores during the pulling out phase is investigated.
Application of Simulation Techniques to Low Permeability Reservoirs
Authors: Ancell K.L. , Young K.L.
Published: December 2007

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

This paper represents an effort to apply simulation techniques to low permeability gas reservoirs. Problems encountered are illustrated by an actual field example. Techniques normally employed for gas reservoirs are not easily extended to the low permeability case. The results show that it is permeability case. The results show that it is possible to rigorously calculate the possible to rigorously calculate the performance of such reservoirs, but to do performance of such reservoirs, but to do so requires data that make application to large fields impractical. However, certain adjustments can be made that approximate performance of such reservoirs, making large performance of such reservoirs, making large applications possible under some restricted conditions.

Introduction

Natural gas transmission companies must invest millions of dollars in surface pipeline systems and compression facilities in pipeline systems and compression facilities in order to produce natural gas and transport it thousands of miles to the market area. These surface systems are designed to fit the specific reservoirs with which they are connected.

In the mid-continent gas supply area, and specifically the Anadarko Basin, many gas reservoirs are characterized by low permeability. Reasonable gas rates that permeability. Reasonable gas rates that satisfy both the transmission company's market requirements and the producer's economics result in large pressure transients existing over extended periods of time. While the pipeline company is basically interested in stabilized well performance, the individual well rates are often determined by short term transient well tests. This makes it necessary to calculate both highly transient and stabilized flow. Numerical simulation techniques would appear to offer the best solution to such a problem. This paper deals with experience gained from simulating a low permeability reservoir and is illustrated with an actual field example.

THE PROBLEM AND DATA AVAILABLE

The simulation of gas reservoirs in the Anadarko Basin requires consideration of low permeability. The extension of techniques permeability. The extension of techniques used for high permeability fields has proved to be not entirely adequate. This study represents an effort to calculate the complete performance of a reservoir that is characterized performance of a reservoir that is characterized by low permeability, then to develop a technique to evaluate such reservoirs in a routine manner.
Geoengineering Confidence Building for the Design and Construction of Salt Caverns
Authors: Langer M.
Published: December 2007

Rock salt is particular impermeable to gases and liquids. The solution-mining method provides the means for the creation of large storage capacities at economic costs. The geotechnical behaviour of rock salt is well-known with sufficient details for dimensioning purposes. Due to its favourable geomechanical properties, halite remains stable over long periods of time without support.

However safety analysis has to be carried out in each case based on specific data. Such an analysis comprises engineering geological study of the site, laboratory and in-situ measurements. Model calculations are essential.

The study of uncertainties is fundamental part of the confidence building. The uncertainty of parameters (geometry, material behaviour, initial conditions, loading) given in a validated model can be expressed by a probability density function, but the model uncertainty is not a stochastic resp. probabilistic attribute. It can be described as a lack of dependability of a model to predict structural response assuming precisely defined parameters, Therefore the objective of model validation exercise must be the demonstration that a model is sufficiently accurate to predict structural response or migration of toxic particles by knowing the logic of idealization or justification of simplification (conservatism).
In-situ Stress Orientation and the Effects of Local Structure – Scott Field, North Sea
Authors: Yale David P. , Rodriguez J. M. , Mercer Thomas B. , Blaisdell David W.
Published: December 2007

In-situ stress orientation was measured in 17 wells throughout the Scott field in order to predict the orientation of waterflood induced fractures. The Scott field is heavily faulted and significant variations in in-situ stress orientation were found between different fault blocks. The in-situ stress orientations appear to be strongly controlled by the orientation of the local faults and tectonics. The direction of maximum horizontal stress appears rotated 30° to 50° on either side of the NNW-SSE regional compression trend generally found in the North Sea. In most cases, the maximum horizontal stress is parallel to the orientation of nearby normal and wrench faults, as would be predicted by a tectonic model of such faulting. However, the tectonics of the region suggest that the rotation of the regional stress field from fault block to fault block is due to the presence of the faults rather than active faulting.

The orientation of the in-situ stress was determined from shear acoustic anisotropy measurements on cores from 5 wells and from wellbore elongation measurements in 13 wells. The two methods show very similar orientations within the same fault block. No statistical variability in stress orientation was noted between different formations or with depth.

Shear acoustic anisotropy utilizes the polarization of shear acoustic waves propagating through oriented core samples and has proven to be very reliable in determining stress orientation. The observed wellbore elongations in the field do not appear due to breakouts. The character, magnitude, placement, and orientation of the wellbore elongations strongly support the premise that the measured elongations were due to drilling or coring induced wellbore fractures. Previous experience by the authors and other recently published observations support this conclusion and the reliability of these elongations for the determination of stress orientation.
A New Managerial Approach of Integrated Contracted Services and Outsourcing Non-Core Activities
Authors: Gardiner A. W. , Monroe J. J. M.
Published: December 2007

If the oil and gas industry is to become more efficient as well as effective the synergies that exist in the business as a whole have to be exploited more successfully. To achieve this, there is a need for a radical change in the roles and responsibilities of oil companies and contractors.

This paper proposes a new approach to gaining greater benefit from exploiting supply management synergies. The approach is based upon the concepts of integrated contracted services and outsourcing of non-core activities. It involves the creation of groups of oil companies to obtain goods and services from the market place through common supply management organisations.
A Novel Approach to Future Marginal Field Development Using Existing Infrastructure
Authors: Cross Linda , Abbott Syd , Hatchwell E. P. C. , Zack J. G. , McGrory K. F.
Published: December 2007

The Ninian partners have developed an innovative commercial framework which will apply to a number of future satellites, dispensing with the often lengthy and complicated process required to develop individual terms for each satellite. The new style agreement promotes the concept of future satellites sharing the Ninian platform topside facilities for processing, metering and export, as well as platform drilling instead of more costly subsea wells where appropriate. This enables potential satellites to be developed simply, quickly and economically.
The Effect of Oil Price and Other Variables on the Timing of and Technology Used in the U.K. Developments
Authors: Howorth Gary , Sales James
Published: December 2007

Fluctuations in oil price has undoubtedly affected development project timing in the last decade. Within the last year some 25 fields in the UK have been delayed by at least one year following a reduction in estimates of long term oil price. The paper derives relationships between field delay and a number of variables and shows that there is an inherent time lag in the UK system of about 1 year. It also demonstrates that the difference between expected and actual oil price is an important determinant of the likelihood of field delay. The paper also shows that use of new technology was accelerated in the UK by a large drop in oil price during 1986. By considering Norway, the paper discusses how the maturity of the industry and the political environment affects the results found in the UK.
Development of a Computer Wellbore Simulator for Coiled-Tubing Operations
Authors: Gu Hongren , Walton I. C.
Published: December 2007

This paper describes a computer wellbore simulator developed for coiled tubing operations of fill cleanout and unloading of oil and gas wells. The simulator models the transient, multiphase fluid flow and mass transport process that occur in these operations. Unique features of the simulator include a sand bed that may form during fill cleanout in deviated and horizontal wells, particle transport with multiphase compressible fluids, and the transient unloading process of oil and gas wells. The requirements for a computer wellbore simulator for coiled tubing operations are discussed and it is demonstrated that the developed simulator is suitable for modeling these operations.

The simulator structure and the incorporation of sub-modules for gas/liquid two-phase flow, reservoir and choke models, and coiled tubing movement are addressed. Simulation examples are presented to show the sand bed formed in cleanout in a deviated well and the transient unloading results of oil and gas wells.

The wellbore simulator developed in this work can assist a field engineer with the design of coiled tubing operations. By using the simulator to predict the pressure, flow rates, sand concentration and bed depth, the engineer will be able to select the coiled tubing, fluid and schedule of an optimum design for particular well and reservoir conditions.
Information Technology Outsourcing One Company's Experience: The Successes and the Lessons
Authors: Klochko J. W. , Bester L. W.
Published: December 2007

Amoco Canada Petroleum Company Ltd. is a $4 billion corporation engaged in oil and gas exploration and production. In October 1992 the company signed a five-year "transitional outsourcing" contract valued at $70 million to $90 million with a leading outsourcing vendor. Amoco Canada like many other organizations, has chosen to outsource information technology services as a way to meet the challenge of reducing costs while implementing technological changes and maintaining services at acceptable levels. Outsourcing is a growing trend as evidenced by a study done several years ago by the Yankee Group, a Boston Massachusetts based information technology consulting firm. They predicted that every Fortune 500 company would consider information systems outsourcing and 20% would outsource at least some portion of their information technology functions by 1994. Recent studies by The Gartner Group suggest that this indeed is happening.

What is outsourcing? In its most basic form it is the purchase of goods or services previously provided internally and is not exclusive to information technology. Information systems outsourcing is not a new phenomenon and in fact has been around since the dawn of data processing. In addition to data processing services it has included, use of contract programmers, time sharing and purchase of packaged software.

A renewed interest in information technology outsourcing stems from its changing nature. Companies are not just approaching outsourcing as a way to reduce costs, as has been the case in the past, but as a strategic tool in the management of information technology. The data centre is now just one of many functions being outsourced. More companies are including the management of local and wide area networks, desktop computer systems, applications development, and midrange computer systems in their outsourcing.
Survey of Computer Use by Petroleum Engineers and Its Implications in Petroleum Engineering Education
Authors: Koedevitz W. L. , Macon B. S. , Schenewerk P. A.
Published: December 2007

Rapid, major advances over the past 20 years in computing capability and the ability to manage information have significantly affected the work of the practicing petroleum engineer. To document the effects of these changes in the workplace, we have conducted a survey of how engineers use computers on the job. Using the results of this survey, we make recommendations concerning the ways in which undergraduate engineering programs should approach computers and computing in the curriculum. The paper also includes a general discussion of why and how computers should be included in undergraduate programs.

One reason computer use should be included in the curriculum is to prepare students better for the workplace. Despite the wealth of evidence that indicates engineers use computers on the job, general information about the actual ways in which computers are used is not available. The survey described in this paper provides a broad, qualitative look at how engineers use computers at work. Moreover, the survey records the opinions of practicing engineers concerning how well their undergraduate education prepared them for computer use.

In addition to the survey results and interpretation, the paper includes interviews and a literature review from engineering education. The survey, interviews, and literature review will be synthesized to provide an explanation of how engineers use computers in the workplace and what implications this use has for undergraduate education. Examples are given from specific curriculum changes under consideration at LSU.