bluuebunny/crossref_metadata_2025_split huggingface dataset:
The Milk River Shallow Gas Pool: Role of the Updip Water Trap and Connate Water in Gas Production From the Pool
Authors: Berkenpas P. G. 
Published: December 2007

ABSTRACT
It has long been known that the Milk River A Gas Pool is located downdip of an aquifer which outcrops in Southern Alberta. In the past numerous suggestions have been made explaining how this unconventional trap of gas below water could exist. These suggestions were without theoretical or practical application. In this paper a theoretical model of the trapping mechanism is described and provides a clear explaination of the phenomenon. It is shown that buoyancy forces are not dominant until pore throats become larger and interfacial tension forces are less than buoyancy. A pressure-depth plot for the Milk River provides additional understanding of the hydrodynamic state of the water and gas in the pool. Application of the theoretical model also provides a basis for understanding edge wells whose production and recoveries are influenced by the aquifer.
Predicting Recovery of Gas Reservoirs Under Waterdrive Conditions
Authors: Hower T. L. , Jones R. E. 
Published: December 2007

ABSTRACT
An analytical model is presented which predicts the performance of gas reservoirs producing under water-drive conditions. The model incorporates a modified water influx technique which accounts for pressure gradients and relative permeability effects across the water invaded region of the reservoir. Under certain conditions in gas reservoirs, these effects can cause significant deviations in predicted performance from that behavior projected using conventional water influx theory. The conditions necessary for this to occur and the improvements realized by using the modified approach are discussed in detail. In addition, the results of the analytical model are compared to solutions generated using a radial, numerical simulator.
Previous work has shown that for water-drive gas reservoirs, ultimate recovery increases with decreasing permeability, trapped gas saturation and aquifer size, and increasing fluid withdrawal rates. However, these parameters are all interrelated. Gas recovery cannot be determined based on one factor without considering the influence of the others. Thus, this paper details the development of new parameters which incorporate the key factors that influence gas recovery. These parameters describe the shape of the p/z performance curves for the reservoir and allow the engineer to estimate the ultimate gas recovery for a particular reservoir/aquifer configuration.
Oilfield Development and Protection of Natural Resources within the Tropical Marine Environment of the Rowley Shelf, Northwest Australia
Authors: LeProvost M. I. , Gordon D. M. 
Published: December 2007

Abstract
In recent years a number of oilfields have been developed in tropical waters of the Rowley Shelf, north-west Australia. Along with Bass Strait and the Timor Sea, this region is the focus for Australia's current oil exploration and production. It supports major coral and mangrove habitats and fishing grounds sensitive to the effects of oil pollution.
Much of the information on the nature and extent of the marine habitats has been gained through survey and monitoring undertaken by oil companies as part of specific development applications in the region.
This paper provides a synthesis of the Rowley Shelf marine environment and reviews procedures protecting the marine resources of the region from the effects of oil spills. Recent government and industry initiatives for improving the protection of the environment are outlined and discussed on the basis of the improved understanding of the marine resources and experience being gained in oil spill contingency planning. The tropical habitats of the Rowley Shelf occur within the Indo-Pacific Zoogeographic Region, therefore experience gained in Western Australia is applicable to similar environments in the South East Asian region.
Pressure-Transient Testing at Drilling Stage of Well Development
Authors: Miska S. , Luo Fang , Lee R. 
Published: December 2007

Abstract
While the DST, RFT and production tests provide useful information for predicting reservoir inflow performance, they require specialized equipment and result in a considerable increase in the cost of operations. Also, conventional, single well pressure transient tests do not provide information on vertical and horizontal permeability. The characteristic feature of the proposed technique is that the test can be conducted by making use of drilling facilities. The tests can be performed at various degrees of wellbore penetration into a formation, hence, the vertical and horizontal permeability can be determined based upon testing of just a single well. The test consists of two major steps. First, a desired drawdown is induced by pumping down the drillpipe and up the annulus a fluid with a density less than the drilling fluid. Upon obtaining a certain amount of oil, the well is shut-in for a pressure buildup. To demonstrate the feasibility of the proposed technique and to reveal the major merits and disadvantages, a computer program has been developed. The simulator enables prediction of flowing and shut-in bottomhole pressures and flow rates under the test conditions if the reservoir and wellbore data are known. Also, the paper consists of the description of the inverse problem. Namely, determination of the reservoir pressure and permeability if the flowing or shut-in bottomhole pressure is given.
Review of Research Efforts in Coalbed Methane Recovery
Authors: Metcalfe R. S. , Yee D. , Seidle J. P. , Puri R. 
Published: December 2007

Abstract
The production of coalbed methane in the United States dates back to the early 1930's. Yet it was not until the early 1980's that research and development projects began to show the enormous potential of this energy resource. These efforts have resulted in the rapid commercialization of coalbed methane production in the United States, including the drilling of almost 800 wells by Amoco. Efforts to evaluate and implement coalbed methane recovery projects are continuing, with current emphasis being placed on worldwide resources.
In recent months, we (and our colleagues) have published almost a dozen papers on coalbed methane production encompassing a wide variety of topics. This paper summarizes the significant findings of those papers and stresses their importance to field operations. Subjects covered include reservoir modeling, pressure transient analysis, rock property measurements, well stimulation, and enhanced coalbed methane recovery. Although most of the work discussed here was done on coals from the San Juan (Colorado and New Mexico) and Warrior (Alabama) Basins, the results are general and applicable to coals in other parts of the world.
A Systematic Approach to Well Design
Authors: Heijnen W. H. P. M. 
Published: December 2007

ABSTRACT
One of our core activities is the design and deployment of exploration and production wells. Since the technology in this area is advancing and therewith the variety of possible well designs it is of paramount importance to re-assess our well design methodology. This paper explains, in concept, the system components and their relationship in performing a well design in a systematic manner. This will provide optimisation of the design as well as providing an audit trail for future performance assessment of the well design. The business aspect and the management of the execution phase will be briefly touched upon in relation with the well design as a basis for technical terms and conditions of a contract as well as Quality Control during the execution phase.
Environmental Protection: Balancing the Risks
Authors: Miller D. N. 
Published: December 2007

Abstract
The pressures on all businesses to manage their environmental performance responsibly continue to grow. Whilst the pursuit of environmental excellence is frequently costly (in financial and resource terms), it is nevertheless fundamental to the continued success of many companies. This is particularly true for companies operating in the primary sector - heightened public and political concern about the environment is reflected in an ever-increasing regulatory burden and in more stringent enforcement of legislation.
Activities such as the development of offshore oil and gas reserves will inevitably have an impact on the environment. This paper will examine the areas of potential environmental risk which these activities pose and review the pressures and potential liabilities for those operating in the sector. It will include an update on the Commission's proposed directive on civil liability for environmental damage caused by waste. It will then consider how risks can be minimised whilst still maintaining efficient and profitable operations.
Examples of best practice, new technology developments and changes in management procedures will be used to illustrate how environmental risks can be minimised.
The Use of Dynamically Positioned Units in Subsea Completions Offshore Brazil
Authors: Moreira J. R. F. 
Published: December 2007

ABSTRACT
The intent of this paper is to document the major accomplishments achieved in the completion/workover of 28 wells using dynamically positioned (DP) units in the Campos Basin. The initial jobs were performed on wells equipped with conventional guideline trees and drilling bases and located in areas congested with subsea facilities.
Minor changes of equipment design and operational procedures, permitted the successful performance of DP units on those conventional equipment.
Based on the experience acquired from the forementioned jobs, guidelineless trees were designed and successfully installed in the Marlim field, at water depth beyond 700 m.
Rig Computer System Improves Safety for Deep HP/HT Wells by Kick Detection and Well Control Monitoring
Authors: Weishaupt M. A. , Omsberg N. P. , Jardine S. l. , Patterson D. A. 
Published: December 2007

ABSTRACT
A drilling contractor has installed and operated on several offshore rigs, a comprehensive data acquisition and computer processing system for realtime monitoring of drilling operations and post event analysis. The system, which includes "smart alarms" for early warning of problems such as kicks, stuck pipe and drillstring washouts, has been extended to cover recent recommendations of the UK Department of Energy for High Pressure/High Temperature (HP/HT) wells.
In this paper we describe the extensions to the system, developed with a major operator, which continuously monitor the return line valve status, mud pumps, choke manifold and BOP stack to ensure that all components are operating within their design limits.
Although the smart alarms for early kick detection reduce the size of an influx, the problem of circulating out a kick remains a hazardous procedure requiring close monitoring. The system's existing realtime displays of log and digital data include a dedicated screen for well control to provide the necessary monitoring.
Additional HP/HT monitors, which continuously display choke position, BOP terrperatures and separator pressures as required for the North Sea, have been added. Hard copies for detailed analysis are produced from a workstation linked to the network.
The development and operation of this system are discussed, and the benefits in terms of improved safety and environmental protection are demonstrated.
Jack-Up Drilling System (J.U.D.S.)
Authors: Cromar S. A. , Schwelm E. R. 
Published: December 2007

ABSTRACT
This paper describes the design and prototype testing of a 15,000 psi, next-generation surface wellhead for jack-up drilling. The system features metal-to-metal annulus seals and an adjustable mandrel hanger which allows space out and permits controlled pre-tensioning of casing strings above conventional mudline suspension systems.
Minimizing Risks in High-Temperature/High-Pressure Cementing: The Quality Assurance/Quality Control Approach
Authors: Vidick B. , Acock A. 
Published: December 2007

Abstract
High-temperature cementing (above 300°F(149°C) remains a complex operation from job design and execution viewpoints. Temperature prediction is of crucial importance and is still a challenge. To design a slurry with excellent properties (thickening time, rheology, stability and fluid-loss) remains difficult in deep hot reservoirs. The execution of the job is also another critical step: accuracy in additive concentration and constant density are not always easy to achieve using normal cement mixing equipment. All these issues make the cementing of a high-temperature/high-pressure well a critical operation. A new global approach is proposed to minimize the risk associated with these operations. Emphasis is placed on quality control of the materials to be used as well as a quality assurance program for the laboratory testing to give confidence in the results obtained. Quality control of the job execution is also heavily emphasized.
Evaluation of Scale Inhibitors for Downhole Squeeze Treatment
Authors: Braley N. J. , Brunt D. C. , Payne G. E. , Wolf N. O. 
Published: December 2007

ABSTRACT
Chemical squeeze treatment with scale inhibitor has been used extensively to combat downhole scale problems in the Murchison and Hutton fields in the North Sea. Considerable success has been achieved for several years. As the fields mature increasing amounts of water are being produced. These increasing volumes of water require ever larger volumes of chemical for control of scale. A review of the chemicals presently available for squeezing was carried out, with a view to obtaining more efficient squeezes, which would in turn reduce costs of scale control. The risk of an unsuitable chemical plugging a well justified considerable effort being expended in the evaluation.
This paper describes the background to the evaluation process which included two new approaches. The ability to monitor accurately chemical returns in the produced fluids is paramount to a successful and efficient squeeze programme. The accuracy of detection methods was evaluated prior to looking at the effectiveness of the inhibitors. The likelihood of formation impairment during the squeeze process was assessed from core studies. Squeeze life ultimately determines squeeze efficiency and simulation of mini-squeezes on cores was used to gauge minimum squeeze life as part of the commercial evaluation.
Drillstem Test and Closed-Chamber Drillstem Test Simulation
Authors: Petak K. R. , Finley D. B. , Coble L. E. 
Published: December 2007

Abstract
The Drillstem Test (DST) has been a popular form of well testing since the early 1900's. To aid in the completion process, the pressure response from a DST can be analyzed to determine formation pressure, permeability, and amount of well damage. A downhole valve is used to control flow into the wellstring in most DSTs. Typically, the reservoir is intermittently flowed and shut-in multiple times. A variation of a DST is a closed chamber DST.
Usually, the DST buildup periods are analyzed by using Homer3 time or Odeh and Selig's5 method. Limited analysis capabilities exist for the flow periods. Most DST analysis techniques lack the completeness to obtain accurate reservoir parameters.
This paper presents a numeric simulator which is used to model DST and closed chamber DST behavior for a wide range of reservoir and wellbore conditions. Because variable wellbore conditions are considered, analysis is more reliable and often possible when other techniques fail.
Reservoir flow into the wellstring is controlled by wellbore and reservoir parameters. In this simulator, wellbore conditions are modelled by using a wellstorage coefficient which is solved at each time step by performing a mass balance on the wellstring fluids. Volume of produced reservoir fluid, rathole mud production, variable cushion pressure, closed chamber air compression, inner wellstring diameter changes, hole deviation, and variable wellstring volume are considered in the calculation. By accounting for these parameters, this model is more complete than existing models or analysis techniques. The wellstorage coefficient is linked with reservoir values to solve for rate and pressure.
Simulated pressure profiles are presented for various reservoir and wellbore conditions. A simulated match of field test data is also given to illustrate the practicality of this work. The strengths and weaknesses of the simulator are briefly cited.
The Offshore NDE and Stress Monitoring of Gas Riser Welds
Authors: Light M. F. , Frazer I. 
Published: December 2007

Abstract
In 1989 a series of study work carried out by Conoco (UK) Limited identified that a number of gas risers could be susceptible to fatigue decay in the region of the riser elbow.
It was considered at that time that further analytical analysis would not add greatly to the confidence in the methods of assessing the long term integrity of these riser elbows.
A decision was made to undertake a work programme that involved detailed underwater NDE inspection of the riser transition welds in question, combined with an offshore programme of stress monitoring. This would provide accurate information on the exact level of wave induced stressing which could then be processed into weld fatigue data.
The offshore work programme was carried out in 1989 and 1990 and the resulting data was used to assess the likelihood of fatigue failure of the risers using probabilistic techniques.
This paper outlines the riser inspection and monitoring programme together with the results and subsequent conclusions.
Testing High-Pressure Gas-Condensate Wells in the UKCS: A Case History
Authors: Wood D. J. , Whitehead N. J. 
Published: December 2007

ABSTRACT
In recent years an increasing number of exploration wells in the North Sea have targeted deep, high pressure, gas condensate prospects. BP Exploration has recently successfully drilled and tested an abnormally pressured Jurassic reservoir with a formation pressure of approximately 15,900 psi and a temperature of 375°F.
Well 22/28b-2 was spudded in October 1988, but following the Ocean Odyssey incident the well was suspended after setting 9-5/8" casing. The well was re-entered in May 1990 using the semi-submersible rig Sedco/BP 711 and drilled to a TD of 5477 mBRT. The reservoir interval was successfully tested from the semi-submersible rig and a maximum shut-in wellhead pressure of 12,300 psi was recorded.
This paper outlines the testing philosophy adopted and discusses the planning, procedures and equipment requirements. It also indicates how the test design was modified in light of changes in the well condition discovered on re-entry.
Beryl Alpha: Increase in Deck-Load Capacity
Authors: Galbraith D. N. , Hodgson T. 
Published: December 2007

ABSTRACT
Fifteen years after the installation of the Beryl Alpha Condeep platform, a programme to upgrade the topsides facilities was commenced. This upgrading increased the overall design weight of the topsides by some 17%. Due to the modular nature of the additional facilities, weight increases of several hundred tonnes each are applied at discrete points around the deck structure.
Prior to this upgrade, Mobil North Sea Limited (MNSL) had commenced the development of reanalysis models of their structures, including the Beryl Alpha deck. A complete reassessment of the strength of the deck was undertaken using detailed finite element analysis and contemporary code checking methods. The methodology used in the checks combined the application of appropriate codes, recent theory, experimental results and both linear and non-linear buckling analyses. Whereas simpler techniques would have suggested a requirement for considerable stiffening, this methodology demonstrated that even the substantial additional loads from the upgrade could be carried with only minor and localised strengthening being required.
This paper discusses the methods used together with the approach adopted for the design of stiffening at minimal cost.
Innovative Technologies Bring New Economical Concepts for Developing Offshore Marginal Fields
Authors: Giannesini J. F. , D’Hautefeuille B. B. , Thomas P. A. 
Published: December 2007

ABSTRACT
After stressing the importance of marginal field developments, especially in the North Sea, the paper describes a new concept based on innovative technologies.
The concept makes use of the multiphase pumping technology recently developed by the oil industry, combined with a small floating support and retrievable flexible fines.
After describing the technical aspects of the system, the paper gives its main advantages compared to traditional development schemes.
A preliminary economical analysis, based on field data, clearly shows the areas of application and the benefit for the oil operator.
The paper concludes on the potential interest of the system to North Sea fields.
Diagnosing Elusive Flow-Induced Turbomachinery and Piping Dynamics Problems
Authors: Jungbauer D. E. , Harris R. E. 
Published: December 2007

ABSTRACT
With the need for increased capacity at existing facilities and the design of larger new systems, flow-induced dynamics problems associated with turbomachinery and piping systems have become more common. These phenomena can result in significant noise and vibration related problems, and potentially lead to fatigue failures. In this paper, a brief review of the characteristics of flow-induced vibration and acoustic phenomenon, as applied to turbomachinery, is presented. A select number of case histories involving on and offshore installations in Europe, the Middle East, and the United States will be presented and involve:
Vortex-excited acoustic resonances of pipeline or gas processing compressor inlet conditioning section. Flow-induced acoustic excitation of safety relief valve piping stubs resulting in excessive vibration and premature venting with loss in production. Acoustic excitation of compressor recycle piping caused by vortex shedding past piping discontinuities.
The importance of meaningful data collection and correlation with existing theory, and the modifications necessary for solution, will be discussed in order to enable design and operating personnel to gain insight as to the impact of flow-induced dynamics problems on safety, reliability, and maximum production.
An Analysis of Formation Damage by Completion Fluids at High Temperatures
Authors: Houchin L. R. , Baijal S. K. , Foxenberg W. E. 
Published: December 2007

Abstract
The use of high density brines has been a major factor in reducing formation damage during completion operations. However, recent studies have suggested that high-density brines can be potentially damaging. More specifically, CaBr2/CaCl2 brines (≥14.2 lbm/gal. [1702 kg/m3]) were found to reduce core permeability from 25 to 29 percent at relatively low temperatures (150°F/51°C). The literature does not address the effects of high-density brines at the elevated temperatures where they are typically in use.
A laboratory study was conducted to determine potential formation damage from high-density brines at temperatures of 250-400°F (94-204°C). Core flow experiments confirm that calcium containing brines produced the most damage at higher temperatures. In addition, at a threshold temperature of approximately 350°F (177°C) all brines have the potential to produce damage.
Numerous operational guidelines have been provided to predict damage potential and identify cost effective preventive measures when high reservoir temperatures are anticipated.