bluuebunny/crossref_metadata_2025 huggingface dataset:
Commodity Price Swaps: A Tool for Asset Management
Authors: Winslow D. J. , Porges D. L.
Published: December 2007

In comparison with the pricing mechanisms that prevailed for crude oil and natural gas from the 1940s through the 1960s, the current price environment is exceedingly volatile. In response to this volatility, financial products called derivatives have been developed in the last decade. Of these, the commodity price swap is finding acceptance as a tool to manage price risk. This paper is an introduction to commodity price swaps for those individuals whose responsibilities include managing a portfolio of oil and gas assets, but who have not had direct experience with swaps. In addition to a description of the basic fixed-for-floating swap and its variations, the historical evolution of swaps is outlined. The significant contract terms and the special problems associated with swaps are also summarized.

Selected applications of commodity price swaps which may be useful in managing a portfolio of petroleum assets are described. These applications include: Locking-in Project EconomicsSwaptionsPrepaid swapsSynthetic oil (or gas) fieldsBTU swaps

Swaps have experienced a rapid growth rate since their introduction in the interest rate and currency exchange markets in the early 1980s. Commodity swaps offer promise as a new tool to those firms which hold a portfolio of petroleum resources, developed or undeveloped.

Note that this paper is not intended as an authoritative reference with respect to the legal, tax and accounting issues associated with commodity swaps. Given the rapidly changing legal and regulatory context of swaps, it is advised that readers seek current opinions from their appropriate legal and accounting advisers.
The Cost Recovery Oil in a Production Sharing Agreement
Authors: Muscolino Riccardo , Rizzo C. A. , Mirabelli Giuseppe
Published: December 2007

Apart from some exceptions, everywhere the State is the owner of the natural resources in its territory.

Therefore, the exploration for oil and gas, being natural resources; entails the execution of agreements between the Oil Companies and the local governments.

Such agreements are governed by a proper contract setting out different items: the area, the duration, the work and/or expenditure commitments, the possible taxation and/or the sharing of production.
Reduced Environmental Impact and Improved Drilling Performance with Water-Based Muds Containing Glycols
Authors: Reid P. I. , Elliott G. P. , Minton R. C. , Chambers B. D. , Burt D. A.
Published: December 2007

Concern over the environmental impact of drilling operations – in particular the disposal of whole mud and contaminated cuttings – is leading to a major reappraisal of acceptable mud types and the way in which they are used. Strict control over the use and discharge of fluids is exercised in, for example, the USA, the North Sea, the Adriatic and the CIS. Government agencies in almost every area of the world are conscious of the potential damage caused by drilling mud and cuttings discharges and are legislating accordingly.

In addition to these legislative pressures, increasing demands are placed on fluids as the industry drills more extended reach, horizontal and high temperature/high pressure wells. These new challenges are in addition to existing ones – such as the need to control reactive shales, provide good fluid loss control and minimise formation damage – which remain critically important to the success of a well.

Given these requirements asked of the fluid, many operators are convinced of the benefits of continuing to use oil based mud (OBM). Hence the industry, including companies such as BP, is committing considerable resources to developing ways of using OBM which comply with good environmental practices. These methods, such as cuttings cleaning and cuttings injection, are discussed by Minton, 1992 and Minton, Begby et. al., 1991.
Method Development Using Field Samples for Assessing Bioremediation Potential
Authors: Wolfram J. H. , Edgmon S. J. , Seidner D. S. , Sturman P. J. , Gawal L. J.
Published: December 2007

Enhanced clean-up of many contaminated sites may be achieved by determining and optimizing the metabolic activity of the native biota present. A method has been developed and tested on contaminated aquifer samples to assess these parameters. The method is reliable and with reduced analytical costs. In addition, engineering a bioremediation process requires that degradation rate information be expressed in a way that can be utilized for scale up.

An enhanced bioremediation phase utilizing the natural flora was undertaken at a producing oil and gas field in Michigan. BTEX compounds emanating from the gas dehydrator system had leaked into the soil over the years of operation. The downward movement of these compounds through the porous sandy soil contaminated the aquifer and migration occurred. The site has been characterized, and monitoring has been taking place since 1988. Presently, the site is undergoing a permitted containment and clean-up treatment.

Laboratory testing of ground water and soil core samples, showed the presence of a mixed microbial population capable of tolerating and degrading BTEX compounds. Results shown in this paper indicate that the levels of phosphorus and nitrogen compounds as well as oxygen are limiting the biological processes taking place in situ. Field samples supplemented with these nutrients were able to remove BTEX compounds at a level of 30-50 ppm to levels below 1 ppb.
Abandonment Pressure Of Gas Wells
Authors: MacRoberts D.T.
Published: December 2007

1962 Economics and Valuation Symposium, Dallas, March 15–16, 1962

When I accepted the invitation to talk on abandonment pressures of natural gas fields I thought the task would be that of consulting various easily-found records, abstracting such data as I thought to bear on the subject, presenting it along with a few apposite observations on my part and the job would be done.

Well, man proposes but God disposes. When I came to examine these records in order that I could, by definite reference, validate my already tailing memory, I found that either they never had existed except in my recollection, or that they had long since been destroyed as of no possible interest to anyone. I felt somewhat as the woman at the zoo who inquired as to the sex of a particular hippopotamus only to be told that such information could be of interest only to another hippopotamus.

After visits to the Conservation Department at Baton Rouge and the Railroad Commission at Austin, after combing our own files for whatever was available, I found myself in that harrowing position of finding that the available data did not agree with my pre-conceived ideas on the subject. As I recall, in my time we produced gas reservoir until the last taint whisper of escaping gas could be heard. Instead of pressure gauges we used water manometers. Our orifice meters — if we were able to measure such minute amounts of gas as were flowing — had one-eighth inch orifice plates.
The Use of Air Sparging in the Remediation of a Production Gas Processing Facility
Authors: Beausoleil Y. J. , Huber J. S. , Barker G. W. , Neumann S. N.
Published: December 2007

A pilot scale field study was conducted at the Amoco Production Company Kalkaska Gas Processing Plant (KGPP) near Kalkaska, Michigan, to assess the efficacy of utilizing in situ air sparging to remediate subsurface BTEX contamination in the aquifer and vadose zone. In situ air sparging is an innovative soil and groundwater remediation technology where air is injected into the saturated zone below the water table to facilitate the volatilization of volatile organic compounds (VOCs). The goals of this study were to: (1) evaluate the potential for enhancing the removal of dissolved BTEX contaminants in the groundwater by sparging air into the aquifer; (2) determine if vadose zone soils at the site contained an indigenous microbial population capable of degrading BTEX contaminants; (3) evaluate the potential for air sparging to enhance microbial numbers and microbial activity in the vadose zone; (4) determine if sparging air into the aquifer enhanced partitioning of BTEX dissolved in groundwater into the advective gas phase with subsequent transport to the vadose zone; (5) evaluate the potential for BTEX in the advective gas phase to be volatilized to the atmosphere; and (6) determine if in situ air sparging causes significant downward or lateral dispersion of BTEX in the aquifer.

A significant decrease in dissolved BTEX contaminants in the groundwater was measured during the four-month study interval. Sparging air into the aquifer did enhance partitioning of BTEX dissolved in groundwater into the advective gas phase and transport to the vadose zone. Laboratory microcosm studies, utilizing soil cores from the study site, confirmed the presence of an indigenous soil microbial population in the vadose zone capable of degrading BTEX contaminants. Selective enrichment of benzene/toluene degraders was noted in the vadose zone as a result of air sparging. BTEX was not volatilized to the atmosphere during the study period and no significant downward or lateral dispersion of BTEX in the aquifer was measured. Results showed that soil vapor extraction (SVE) wells and surface treatment of VOCs may not be necessary during in situ air sparging. Consequently, remediation costs could be significantly reduced. This study supports the results obtained in earlier field trials by Amoco Production Company and provides additional evidence for the viability of in situ air sparging as a low-cost remediation technology.
Modem Transmission of Data for 3-D Fracture Modelling
Authors: Chaudhary S. A. , Rodgerson J. L. , Martinez A. D. , Alexander M. C.
Published: December 2007

Hydraulic fracturing treatments require measurement of numerous parameters including surface rates and pressures to quantify the fluids, proppant and additives being utilized. Computers are used to acquire data for the purpose of calculating bottomhole pressure, compiling quality control data, generating diagnostic plots and, on occasion, for modelling fracture geometry in real-time.

In the recent past, modems have been routinely utilized in conjunction with cellular phone systems to transmit field monitored data to a remote office. More recently, this data has been used at the remote site to perform 3-D fracture modelling for design verification and adjustment. A description of the data transmission technology is presented and a discussion of the related cost and reliability made. A field example Is provided which involves the use of realtime 3-D analysis at the remote location.

Remote transmission of data offers a major benefit to operators by providing the ability to monitor treatments and communicate requests or queries over the phone during the execution of a job. Since reports and pertinent job information are immediately available at the remote location, it is possible to perform more sophisticated real-time analyses at a lower cost.

In the past, remote transmission of data has not been practical due to the related cost and technological difficulties. Recent advances in technology, such as the wide availability of cellular phone coverage, however, have made it both cost effective and reliable. Although the frequency of "noise" and lost connections is typically low, these problems can be handled by implementing an error correction/recovery scheme. This technique ensures a continuous flow of information.
Technical Computing – Asset or Liability?
Authors: Fritz A. A.
Published: December 2007

Technical computing in the oil and gas industry has undergone tremendous changes during the past ten years. Applications initially developed in BASIC, spreadsheet programs, FORTRAN, etc. have advanced into multifunctional, integrated products that are portable across several platforms (various computer systems).

One aspect that has not kept pace with these technological advances is support. As in other businesses, a product, service or line of business that is not properly supported will quickly falter and subsequently be dropped. Support is critical in turning a product or business line into an asset.

Technical computing should be viewed in the same light. Hundreds of thousands of dollars can be spent on technical applications, hardware, training, etc. Such investments should be viewed as adding value to a company's asset base. Without clearly defined support roles and responsibilities, these investments can quickly become non-performing assets or even liabilities.
Modified Poly-Amino Acid Hydration Suppressant Proves Successful in Controlling Reactive Shales
Authors: Bruton J. R. , McLaurine H. C.
Published: December 2007

Drilling fluid additives used for controlling water sensitive smectitelillite shale formations are varied, ranging from anionic components such as high-molecular-weight pofyacrylamide (PHPA) "encapsulating" polymers to complex low-molecular-weight, high charge density cationic compounds. Many of these additives are used in conjunction with salts such as potassium chloride (KG) to enhance the inhibiting effects of the drilling fluid. The performance of these additives have been adequate in many reactive shale environments but some systems have not completely resolved drilling problems or they lack flexibility in terms of mud density, contamination, environmental toxicity, or product compatibility limitations.

A unique drilling fluid additive compound has been developed, a modified poty-amino acid that resolves the limitations inherent in other additives, providing a wide range of flexibility and applicability in most water-based mud formulations. Functionally, the compound may be described as a hydration suppressant (HS), limiting the ability of smectite clays to hydrate and swell when exposed to water. HS has a low molecular weight and a low charge density and possesses

an amphoteric ionic character. HS is water soluble, exhibits high thermal stability, and environmental testing shows the additive to be safe for use in offshore drilling projects. Fluid formulations have been developed and performance tested. The additive has been found to be compatible with most anionic and cationic compounds, including salts, while improving the drilling fluid system’s ability to retard clay hydration. Testing and analysis shows that HS only affects reactive clays that have not yielded. The yield of pre-hydrated bentonite will not be diminished by the addition of HS nor will the performance of conventional polymeric fluid-loss-control agents.

HS has been used on several field trials in both onshore and offshore locations, and in freshwater and seawater systems of varying mud component composition including dispersed and non-dispersed systems. In all cases to date, documented improvement in fluid and drilling performance have been noted.
Permian Basin Coring Cost Cut by One-Third Over a Long Cored Interval Using Innovative Coring Techniques
Authors: Bretches D. C. , Shields J. E. , Harder C. A. , Hagins F. W.
Published: December 2007

The cost effective cutting of large intervals of continuous core in dolomitic formations requires optimization of existing coring practices. Coring costs can be reduced as much as 38% when innovative techniques are applied to the coring operation with regard to core barrel spacing, core barrel modification, and proper bit selection to include the use of polycrystalline diamond compact (PDC) bits and thermally stable diamond (TSD) bits. In addition, high percentage core recoveries and reduced problem time can be attained through teamwork and incentive arrangements between the operator and coring service company.
An Overview of the Environmental Issues Facing the Upstream Petroleum Industry
Authors: Reis J. C.
Published: December 2007

For many petroleum engineers, the depth and complexity of environmental issues facing the industry can be overwhelming. Although many excellent papers have been presented on specific environmental areas, overview papers that provide a context for those more specialized studies are needed. This paper reviews the primary sources of wastes in the upstream petroleum industry, the environmental impacts of those wastes, ways to manage, treat, and dispose of wastes, and cleanup methods for contaminated sites.
Drillsite Cost Savings Through Waste Management
Authors: Ballantine W. T.
Published: December 2007

The best way to limit a company’s liability and exposure to environmental problems is by limiting the amount of waste generated in the first place. This paper suggests techniques through which environmentally managed operations can reduce and limit an operator’s cost exposure related to waste clean up and, ultimately, the operator’s liability.

At a new drilling location, a native soil test should be performed and a historical background check in the assessment will discover if a well has been drilled in this location previously. There is the possibility of a previously buried pit or other environmental problems that are preexisting on the location. The native soil test will give the operator a background signature.

During the planning and drilling of the well, the chronological progression of the well should dictate how the waste generated is managed. By building a multiple pit system rather than single pit, the amount of waste that would have to be disposed of can be reduced. The top hole can be segregated in one pit and later spread around the location. As the well progresses, salt water, weighting material, etc., can be handled in various pits and treated specifically to minimize the waste. If all material is placed in one pit, all becomes waste to be handled for disposal.

For pit clean ups, a thorough assessment should be accomplished to identify the extent of contamination, the location of the clay liners and the boundaries of the waste. These boundaries, once established, should not be violated as the pit contamination could be spread into a surrounding sand, resulting In enlargement of the contamination. These assessment techniques can ultimately result in minimization of the waste to be cleaned up and disposed.

There are numerous techniques that can be utilized to minimize waste in drilling and production operations. When carried out properly, what they do is eliminate the generator’s liability.
An Overview of Ad Valorem Taxes
Authors: Olds D. R.
Published: December 2007

Ad valorem taxes are property taxes generally assessed and levied at the local level. Each state usually proscribes the evaluation method, with two major approaches to oil and gas properties being common: basing the assessment on the level of prior production or using a discounted cash flow model to project the future value. Tax rates can vary widely in the local taxing entities, and a county or parish may encompass many different taxing entities.

This paper briefly surveys the approaches taken to ad valorem taxation on oil and gas properties in producing states.
Results of Two Polymer Flooding Pilots in the Central Area of Daqing Oil Field
Authors: Wang Demin , Hao Yuexing , Delamaide Eric , Ye Zhonggui , Ha Si , Jiang Xiangcheng
Published: December 2007

Two polymer pilot tests (PO and PT) have been performed in the Central Area of Daqing Oil Field. The purpose is (1) to study further the economic benefits of polymer flooding in thick heterogeneous reservoirs, (2) to provide some technical and practical experiences for expanding this technique to other areas of Daqing Oil Field.

During the polymer pilot tests, a large amount of performance information (such as injection pressure, injection profiles, C/O logging, tracer tests, core data from inspection wells, salinity of effluent fluid as well as the concentration and viscosity of polymer solution in the injected and produced fluids etc.) were collected. In this paper, the results of the polymer flood were evaluated comprehensively by analysing the information. Good results were obtained in the polymer pilot tests. The volumetric sweep efficiency and oil production were all increased. Incremental oil production is more than 200 tons per ton of polymer injected. Oil recovery increased more than 11 %of OOIP. All of these confirm that polymer flooding is very applicable to Daqing Oil Field.

In the course of evaluating the results, follow-up matching and result prediction of the polymer flood were performed by numerical simulation. In order to obtain the best economic results, when executing the design or adjusting the project, a new "normalized method" was developed. By applying this method, the results of polymer flooding were evaluated at different stages.

This paper demonstrates the effect of Dykstra Parsons permeability coefficient (Vk) on polymer flooding results and presents a optimum range of the Vk value applicable for polymer flooding in Daqing Oil Field. The relationship of the amount of polymer injected versus economic results and the polymer flooding result in multi-layer reservoirs are also discussed and opinions are given. All of these are important to later project design and result evaluation of polymer flooding in Daqing Oil Field.
Retrospective Evaluation of Foreign Investment by an Independent Oil Company
Authors: Ventura J. L.
Published: December 2007

During the last few years, several U.S. companies have made the decision to expand internationally. This decision is the result of several factors, including the large acreage positions and reserve potential that exist overseas, coupled with foreign governments that are offering favorable investment environments in order to attract new capital and technology. International expansion offers unique challenges and opportunities. This paper is a case history of the international growth of a U.S. independent, Maxus Energy Corporation, from 1987 to 1992. It examines the key international exploration and production challenges that Maxus faced in 1987, looks at problems faced and accomplishments made in subsequent years, and identifies challenges for the future.
International Gas Strategies: Political, Corporate, and Financial Considerations
Authors: Jones P. J. , Lau W. A.
Published: December 2007

The international gas industry will come of age in the 1990s. Gas demand is currently exhibiting an average rate of growth significantly greater than that of oil. Growing environmental concerns, the availability of significant volumes of undeveloped natural gas reserves discovered in the past decade, and the dramatic changes in the socioeconomic-political arena (leading to the global privatisation effort currently in progress) have set the stage for the natural gas industry into the next millennium. The future prospects for the international gas business are now sufficiently attractive to warrant serious consideration by all significantly-sized petroleum companies. The business opportunity spectrum for gas encompasses exploration, development, production, transmission, marketing, liquefied natural gas, electrical power generation, primary petrochemicals and automotive transportation. The development of appropriate strategies to capitalise on such opportunities depends mainly on the nature of the company pursuing the opportunity, the nature of the opportunity and/or the number of opportunities pursued. Also important are potential political, legislative and environmental developments.

Some of the more far-sighted companies are positioning themselves to participate actively in this rapidly growing sector, generally via a strategy of integration along the value-added chain. In this respect, the knowledge and expertise base required of such participants, if they are to establish profitable business activities, is much more extensive than that required of typical oil companies. The competitive advantage in this capital-intensive, long lead-time business sector lies with integrated companies with proven experience in all phases of gas operations. Companies without an effective, comprehensive strategy are unlikely to make any significant progress in the sector in the medium term unless they are prepared to pay large acquisition premiums. This paper reviews the anticipated evolution of the natural gas business, the major developments contemplated, and political, corporate and financial considerations.
Enhanced Organizational Teamwork: Continuously Improving Business
Authors: MacFarlane Sandy , Flynn Sharon
Published: December 2007

The current work force is increasingly well educated. Employees want more than monetary compensation for their time and effort. Employees want to be involved in the process of running a department, division, or company. Involvement not only improves business, it obtains employee commitment to business objectives. Employee participation builds a powerful work force. BP Exploration in Anchorage, Alaska (BPXA) set out to harness that power through a series of initiatives that included the process called Enhanced Organizational Teamwork.

Enhanced Organizational Teamwork (EOT) is a continuous improvement process that delivers business performance. This paper introduces culture change and how the EOT process fits into that larger context. The paper describes the philosophy supporting the process, EOT’s successes, limitations, and lessons learned, its manpower requirements, results two years later, other potential applications, and a logical next step. This paper outlines the roles and responsibilities of all groups involved in the process from senior management to hourly technicians and the benefits of their participation, individually and collectively.
The Design and Development of Microwave Holdup Meter and Application in Production Logging Interpretation of Multiphase Flows
Authors: Haimin Guo , Xiling Wu , Zhenwu Jin , Hongmin Zhao
Published: December 2007

A lot of field testing demonstrate that the fluid capacitance instrument usually miss the ability to distinguish water from oil and gas in high water cut production well(water cut>40% or water holdup >0.5) which is dominant in china. In order to solve this problem, The effect of water salinity and flow pattern to measurement result is eliminated by improving work frequency( > 100MHz).

The microwave holdup meter, which is suitable to oil/water two phase and oil / gas / water three phase wells measurement, can accurately measure water holdup from 0 to 100% and is not’ sensitive to water salinity. Flow loop calibration data and practical examples are presented for the microwave holdup meter.

This kind of instrument can be used for determining the water holdup of multiphase well(high water cut or lower water cut) in production logging interpretation.
A Pressure Moment Approach for Helping Pressure Transient Analysis in Complex Heterogeneous Reservoirs
Authors: Noetinger Benoît
Published: December 2007

Numerical simulation of pressure-transient tests in complex reservoirs is a growing interest topic in Reservoir Engineering. The aim of this paper is to build interpretation tools for synthetic well-tests in such geometries when classical analytical models are not applicable.

An approach based on moments is proposed. It consists in the evaluation of the time-variations of simple spatial global properties of the simulated pressure-field. It provides at a negligible extra CPU cost a precise evaluation of the size of the drainage zone, as well as an alternative very simple determination of the reservoir equivalent porosity and permeability. It avoids a rather imprecise Log (t) interpretation, gives the main time-scales and lengthscales of interest and the occurence of reservoir-boundary effects. Such an approach is a first step toward an integrated interpretation of well-tests in complex reservoirs linked to a reservoir simulator. Simple mathematical elements, as well as numerical and practical examples of its use over geostatistically generated reservoirs are given.
A Hybrid Simulation Study of the Windalia Sand Waterflood
Authors: Emanuel A. S. , Tang R. W. , McKay D. M. , Ellis M. H.
Published: December 2007

The Windalia reservoir is a 22,000 acre, 600 well oil reservoir with a 25 year waterflood history, complicated by stress induced fracturing and a major pattern realignment. The reservoir recovery performance was studied by an integrated combination of geostatistical, finite difference, and stream tube models. The methodology is an extension of previously published work1 to larger and more complex reservoir problems. The basis of the approach is a geostatistical reservoir description derived from well logs and core data. Fine grid 2-D and 3-D models are developed to correlate sweep efficiency as a function of characteristic reservoir stratigraphies. These correlations are translated into fractional flow functions and pseudo relative permeabilities which are used in full field stream tube models and 2-D areal finite difference models. The stream tubes provide recovery calculation and front tracking and the areal model provides a calculation for pressure and well productivity. The methodology provided a reasonable representation of the reservoir and its well histories for an efficient expenditure of labor and computer time. Model construction, well history matching and forecasts were completed in four months, a significant improvement over previous attempts to model this reservoir. Refinement, update and sensitivities continue as a reservoir management process.
A Novel Approach to Reconciling the Problems of Acquiring Diplog Data
Authors: Bigelow E. L. , Civarolo M. F. , Fishburn T. K.
Published: December 2007

After a rigorous and dedicated period of field testing, a new-generation hexagonal dipmeter device is commercially available throughout most of the world. A unique powered standoff is a component part of the new 6-pad device. The powered standoff is located below the dip-pad section, enabling adequate standoff of the tool mandrel in boreholes at any deviation angle while removing the effect of mandrel weight from the dip pads. Prior to this uniquely designed equipment, dipmeter tools employed pad force from the dip pads themselves to attempt mandrel standoff, often resulting in less than desirable log data for processing purposes. A recently developed dip-processing package is used to illustrate results obtained from the hexagonal dipmeter.
Development of Coiled-Tubing-Conveyed Thru-Tubing Inflatable Selective Stimulation Tool
Authors: Coronado M. P. , Mody R. K.
Published: December 2007

Within the past year, an inflatable Thru-Tubing Selective Stimulation Tool (SST) has been successfully field tested, and has proven to be a valuable alternative to a conventional rig workover stimulation method. Use of this system eliminates the inefficient use of ball sealers or chemical diverter methods for perforation isolation, which often yield questionable results. The Selective Stimulation Tool has been designed primarily for coiled tubing applications, and the unique design aspects of the tool will be discussed which allow safe coiled tubing conveyance of the system. Since the SST is designed to run through the production tubing and work in the casing below, the need to pull the completion prior to the job is eliminated. This provides economic advantages in both the amount of equipment required and time spent on the job, since the well does not have to be re-completed after the treatment. Using coiled tubing as a workstring also allows the operation to be performed while the well is live. This eliminates the need to kill the well with heavy weight kill fluids, which may cause formation damage.

The SST utilizes dual inflatable packing elements for interval isolation to allow the precise placement of treating fluids within the wellbore. The tool is resettable, allowing a complete zone to be treated with only one coiled tubing trip in the hole. The development of this tool system has also accelerated the technical evolution of other thru-tubing and general inflatable element designs to increase their performance. The development and history of the inflatable element used for the SST system will be discussed in this paper.

This paper also outlines the design criteria used during the development of the tool system and the testing done to qualify the new inflatable element design. A description of the tools’ basic components will be included along with a summary of the different operational positions of the system.

In addition, a discussion of field applications completed to date will also be covered, as well as possible future operations which may utilize this new tool system.
Trends for Future Development Planning in the Norwegian North Sea
Authors: Arneberg J. E. , Guenther K. T. , Brandsøy Asleiv
Published: December 2007

The paper presents an assessment of trends for development of future discoveries in the Norwegian sector of the North Sea. The key parameters affecting decisions on commercial development of smaller marginal fields are examined. Trends in investment cost, development technology, and project economics are discussed. Technologies and strategies that are expected to have a positive impact on future developments are discussed. Development trends are considered from the perspective of future oil price changes.

The information provided in the paper supports the following observations and conclusions: There is likely to be a high level of exploration and development activity in the Norwegian North Sea over the coming decades, but the trend will be clearly toward development of smaller fields supported by existing infrastructure.Commercial conditions for utilization of infrastructure are critical for development decisions and the selection of technology.
Materials Engineering in Marginal Field Developments
Authors: Mohagen S. T. , Houghton C. J.
Published: December 2007

This paper discusses the important role of materials engineering in contributing to the successful development and operation of marginal fields in the offshore environment, with particular reference to recent Phillips Petroleum developments in the UK and Norwegian sectors of the North Sea.

The applications of alternative materials, such as aluminium alloys and coatings, high alloy stainless steels and GRP (glass reinforced plastics) are discussed, highlighting the benefits and limitations as currently perceived. In conclusion, the paper reviews some of the issues, both technical and economic which may impede future possible applications of these materials.
Continuous Gas-Lift Instability: Diagnosis, Criteria, and Solutions
Authors: Alhanati F. J. S. , Schmidt Zelimir , Doty D. R. , Lagerief D. D.
Published: December 2007

This paper presents field data that show how continuous gas lift instability is manifested. It also reviews former proposed criteria to predict the phenomenon. The best available criteria are selected and expanded to take into account different flow regimes for the surface gas injection valve and the bottomhole gas-lift valve. The expanded criteria are examined using field data. The criteria clearly show the relative importance of the different factors involved, and thereby help to assure stable flow conditions at the design phase or to decide what actions to take in order to stabilize an unstable gas lift well.
Improve Primary Cementing by Continuous Monitoring of Circulatable Hole
Authors: Ravi K. M. , Beirute R. M. , Covington R. L.
Published: December 2007

Previous research has demonstrated that proper hole conditioning is critical to successful cementing operations. However, in the past, there has not been a reliable technique available to the industry to continuously monitor the volume of hole circulating. Liquid calipers (tracers) are difficult to run and cannot be run continuously to know how the well is cleaning and when the well is ready for cementing.

This paper discusses a reliable technique to continuously estimate the circulatable hole during hole conditioning. This should provide the operator with a much better tool for improving the success of cement jobs. The method consists of making very sensitive measurements of surface pressure during circulation. A software package was developed to estimate the hole volume circulating from surface pressure, the fluid circulation rate, and fluid properties. The package makes corrections for pressure drop across casing attachments such as float shoes/collars and centralizers.

The technique was demonstrated in a research well. Casing was run with attachments to simulate actual field conditions. Static and circulating periods as well as pipe movement were used as data was collected for several days. The effect of static periods, fluid circulation rates, fluid properties, and pipe movement on circulatable hole was clearly observed from these tests. To validate the continuous circulatable hole measurements, dye tracers were used to measure the circulatable hole. These measurements were in good agreement with the real time data from the proposed technique.

The proposed technique works in actual wells. It allows continuous estimation of the effect of static periods, fluid circulation rates, pipe movement etc. on circulatable hole. The technique can be used to tell when the well is ready for cementing.

The new technique will be very easily applicable to the field. It requires a sensitive pressure transducer at the wellhead, a reliable flowmeter, and properties of the fluid.
Efficient Modelling of Asphaltene Precipitation
Authors: Nghiem L. X. , Hassam M. S. , Nutakki Ram , George A. E. D.
Published: December 2007

An efficient modelling technique based on the representation of the precipitated asphaltene as a pure dense phase is presented. The success of the approach is based on the division of the heaviest component in the oil into a non-precipitating and a precipitating component. The characterization of these components is discussed. This model was able to make quantitative predictions of experimental data from the literature as well as additional data from industry. This was achieved with only a small number of adjustable parameters (two or three). The mechanistic aspect of the model with regards to colloidal nature of asphaltene/resin micelles is also discussed. An algorithm for three-phase flash calculations with asphaltene precipitation is described.
Pressure-Volume-Temperature Correlations for Gulf of Mexico Crude Oils
Authors: Petrosky G. E. , Farshad F. F.
Published: December 2007

New empirical PVT correlations for estimating bubblepoint pressure, solution gas-oil ratio, bubblepoint oil formation volume factor and undersaturated isothermal oil compressibility have been developed as a function of commonly available field data.

Results show that these PVT properties can be predicted with average absolute errors ranging from 0.64% for bubblepoint oil formation volume factor to 6.66% for undersaturated isothermal oil compressibility.
A Cost-Effective Oilfield Brine Treatment Technology
Authors: Safargar M. R. , Tian Shifeng , Heckman S. W. , Watson R. W. , Adewumi M. A.
Published: December 2007

Stripper wells generally produce formation brine along with oil. In order to meet the discharge criteria established by federal and state environmental agencies, and to sustain continued production from these marginally economic wells, this brine must be treated in a cost-effective manner. This paper presents the research efforts leading to such a technology
Economic and Technical Rationale for Remediating Inefficiently Producing Eastern Gas Shale and Coalbed Methane Wells
Authors: Kuuskraa V. A. , Reeves S. R. , Schraufnagel R. A. , Spafford S. D.
Published: December 2007

During the past five years, nearly 10,000 Antrim Shale, Devonian Shale and eastern coalbed methane wells have been drilled and completed in eastern basins. A portion of these new wells (and previously drilled, older wells) appear to have been inefficiently completed, stimulated and produced, due to limited understanding of the production mechanisms and lack of sound data on the interaction of drilling fluids on the shale or coal reservoir. Thus, substantial improvements may be achieved by remediating these wells. The economic incentives for remediation are particularly powerful. Successful remediation not only provides additional low cost gas production but may also provide additional Section 29 tax credits.

In the Antrim Shale, remediation involving pump refracturing and completion of additional zones have led to substantial gains in gas production. However, the identification of wells requiring restimulation has been more challenging. Pressure buildup testing and productivity index matching have been utilized to identify such candidates.

In the Warrior Basin, restimulation of poorly producing wells has had more mixed results. Based on the experiences learned from the GRI Rock Creek Field Laboratory, a remediation program is being initiated in the Warrior Basin with support of GRI and basin operators.

This paper sets forth a technical and economic rationale for a remediation research and deployment program for eastern gas shale and coalbed methane wells. A series of case studies summarize some of the results achieved to date.
Rate Decline of an Arbitrarily Positioned Well in Composite and Irregular Reservoirs
Authors: Zhang WenXia , Chu Lifu , Grader A. S.
Published: December 2007

Transient rate analysis is currently focused on infinite or circular reservoirs with concentric wells. Rate decline responses for a constant pressure well which is arbitrarily located in a regularly or an irregularly shaped reservoir or in a composite reservoir are not documented in the literature. This paper presents two new solution techniques for rate decline behaviors in such complex systems. For the composite model, the analytical Laplace solution is based upon placing a constant pressure well with an arbitrary location in a two-composite radially concentric domain. By varying the properties and the geometries of the domains, the new model provides several new settings for transient rate analysis. The paper discusses the characteristic responses of such composite systems. In the case of an arbitrarily shaped drainage area, the external boundary is replaced by a group of line source boundary wells. The paper outlines the criteria for placing these wells to create the effects of the boundary. This semi-analytical method permits us to study rate declines in cases that cannot be studied analytically.
Using Tracers To Evaluate Propped Fracture Width
Authors: Holditch S. A. , Holcomb D. L. , Rahim Zillur
Published: December 2007

Many production engineers are beginning to use threedimensional (3-D) fracture propagation models to design and analyze hydraulic fracture treatments. To use a 3-D model, one must define the layers that comprise the reservoir and develop detailed datasets that accurately describe the layers.1,2,3 The data that are critical for designing and analyzing hydraulic fracture treatments are in-situ stress, formation permeability, formation porosity, reservoir pressure, and Young's modulus. Many times, these parameters can be determined from logs and/or correlated to lithology.

Once the datasets are obtained, one can use a threedimensional fracture propagation model to estimate values of created or propped fracture length, width, and height. To understand and improve the fracture design process, the engineer must confirm the estimates of fracture dimensions that are predicted by a fracture propagation model. To verify the model, one must analyze field data to be sure the field data are consistent with the model results.4 For example, the net pressure predicted by the 3-D fracture propagation model should closely match the net pressures observed in the field. When net pressure is adequately matched, we usually find that the overall created fracture dimensions predicted by a 3-D fracture propagation model are reasonable. To determine estimates of propped fracture length, one must also analyze post-fracture production and pressure transient data. Because of fracture fluid cleanup problems, we often find that values of propped fracture length generated by analyzing field production data are much shorter than the created fracture length predicted by the fracture propagation model.5 Detailed engineering studies are often required to reconcile the differences.

To directly measure values of fracture width, one must perform a fracture treatment in openhole, then use a downhole imaging tool to "see" the fracture. Such an approach is not usually practical. In this paper, we will describe a method to qualitatively estimate the propped width profile at the borehole that uses radioactive tracers. Confirming the propped width profile generated by a model with field data can be very beneficial and informative.

We have found that the use of zero wash radioactive tracers can help us learn both (1) where the fracture fluid is going and (2) where the proppant resides in the fracture near the wellbore.5,6 Assuming the level of radioactivity is proportional to volume, then the level of radioactivity will also be proportional to the propped fracture width. As such, one can obtain qualitative estimates of propped fracture width at the wellbore using a radioactive tracer where the strength of the radioactive signal is proportional to fracture volume near the wellbore.
TREAT: Transient Response Evaluation Advisor Tool
Authors: Izarra L. A. , Montero A. E. , Alvarado R. W.
Published: December 2007

A user-friendly expert system was developed for the model diagnosis in well test interpretation. The perplexing difficulty arising from the nonuniqueness of the transient response, is significantly diminished with this expert system. This knowledge-based application combines available theoretical models with the technical expertise and know-how of the human analyst. This tool provides two complementary means for model diagnosis and selection, namely pattern recognition with the pressure derivative function and a historical module containing previous test responses for cross-references.
Role of Well Test Quality Control in Reservoir Description
Authors: Prat G. Da
Published: December 2007

In this work first a brief summary is given to the operational procedure used in the field to acquire well test data. Also the methodology used for data analysis and interpretation is presented. The main objective of this work is to present the impact that the quality of the acquired data will have on reservoir management and description. The procedures used to assure that the data being recorded during a well test has the best quality are presented. The most important conclusion derived from this work is that even though in the interpretation of the reservoir model derived from testing data we may find inconsistencies or anomalies, they are due to the elaboration of a reservoir testing model based on poor data quality.
Reactivation of Marginal Fields
Authors: Orunesu R. A. , Hernández J. M.
Published: December 2007

This paper describes the methodology applied for the evaluation and reactivation of a field that was considered marginal for many years: Challacó Field, located in the Neuquén Basin, 70 km from the city of Neuquén. Figure No 1.

The study carried out made it possible to have a precise volume of reserves and a program of operations for their production. Such study was performed prior to the beginning of the operations, minimizing risks and uncertainties.

One of the most important factors to be taken into account is the necessity of a good understanding of the reservoir in order to increase the possibility of success in any intent of reactivation of any field.

The permanent implementation of a complete study of Geology and Engineering of Reservoir will allow to increase the factor of hydrocarbons recovery in place, thus incorporating an important volume of reserves in a more economical way than the ones obtained in some cases by means of exploratory conventional techniques.

Most of the reserves of our country and of the world can be surely found in fields that have been or actually are subexploited due to different reasons, political, economical, etc., and in many cases to lack of investments in reservoir studies.