bluuebunny/crossref_metadata_2025_split huggingface dataset:
Cost-Effective Recompletions of Fruitland Formation Coalbed Methane Gas Wells are Achieved With PDC Technology-Based One-Trip Sidetracking and Lateral-Drilling Technique
Authors: Nye Bruce , Reid Dave , Childers Ronald D. , Miller Gregory C. , Sanchez Eppie 
Published: December 2007

Abstract
Sidetracking mills designed with PDC insert cutting structures were able to effectively mill a casing window and drill the required lateral in one trip. This new application of advanced PDC technology in Fruitland Formation coalbed methane gas wells provides cost and timesaving benefits. This progressive effort by the operator to improve efficiency and to optimize the recompletion procedures for San Juan Basin wells is furthering exploitation of hydrocarbon reservoirs.
This paper discusses how mills designed with PDC inserts swiftly cut steel and drill formation to produce a lateral well bore from the mother bore. The technique reduces the number of trips, equipment, costs, and time required to recomplete the well. The operator is able to minimize loss of production on a downed well by getting the well back on-line sooner.
Three case histories are presented that illustrate how this new technology and technique were first applied in the San Juan Basin and further developed through their utilization to recomplete coalbed methane gas wells.
Flow-Induced Stress Reorientation in a Multiple-Well Reservoir
Authors: Hidayati Dewi Triarti , Chen Her-Yuan , Teufel Lawrence W. 
Published: December 2007

Abstract
Flow-induced stress change causes redistribution of stresses in reservoirs which can lead to reorientation of principal stresses. Stress reorientation has direct impact on fracture orientation and thus drainage or flood pattern. Consequently, drainage or flood pattern after certain time of production/injection may be different from the original expected pattern. Stress reorientation in a multiple-well reservoir is studied to determine the controlling parameters. An analytical-based, coupled fluid-stress model is adopted for this study. Multiple wells and variable flow rates are handled by the principle of superposition. Result shows that flow-induced stress change can cause principal stress direction to undergo from gradual to sudden reorientation, or to remain unchanged. Their occurrences are time and space dependent, and determined by initial stress anisotropy, permeability anisotropy, flow mode (injection/production), and flow rate. Well interference is also identified as an important factor affecting stress reorientation. Examples of application using stress trajectories to infer fracture orientations are presented.
Environmental Aspects Of Enhanced Oil Recovery
Authors: Scott Robert M. , Zwicker Stanley L. , Jonker Peter E. 
Published: December 2007

Introduction
The future application of enhanced oil recovery (EOR) technologies will undergo a very complex governmental approval process. Reviews will be conducted in the areas of air quality, water quality, protection of drinking water, toxic substances, and solid or hazardous waste management. As a result of these reviews, projects involving new technologies or the expanded use of existing technologies may face significant delays.
This paper traces the oil industry's permitting problems in California through the labyrinth of federal and state laws and regulations. Analysis of the role these environmental constraints may play in future EOR projects is also attempted.
On the impetus of federal and state government, California has recently been at the cutting edge of environmental controls. The entire domestic oil industry would be well advised to understand the regulatory role that has developed in California and incorporate that knowledge into the EOR planning process.

ENHANCED OIL RECOVERY TECHNOLOGIES
A technical discussion of the various facets of enhanced oil recovery technologies is reserved to other sources. This paper will concentrate on the impact that existing and developing laws and regulations will have on EOR activities. For organization purposes, three groups of technologies can be identified:ThermalMiscibleChemical
By examining the known and potential permitting problems that the use of thermal technologies may encounter, it is possible to address most of the problems that can be expected by the other technologies. The use of chemical EOR technologies will face a unique set of obstacles which will be examined separately.

THE LAWS AND REGULATIONS
Since the "great environmental awakening" of the late Sixties, Congress has enacted several major pieces of legislation to protect the nation's environment. These laws in turn spawned many state, regional, and local regulatory and planning activities. The scope and impact that these regulations will have on the economy and on specific industries is beginning to be understood.
The following is a partial list of the major pieces of federal legislation and some of the important ongoing programs that will, and are, directly affecting EOR activities:The Clean Air Act (CAA) of 1970PL 91–604, and the Clean Air Act Amendments (CAAA) of 1977, PL 95–95 and PL 95–190.Revisions of the State Implementation Plans (SIP).Air Quality Maintenance Planning (AQMP)Federal and state preconstruction review, e.g., New Source Review(NSR) and Prevention of Significant Deterioration Review (PSD).
Direct Geostatistical Simulation With Multiscale Well, Seismic, and Production Data
Authors: Tran Thomas T. , Deutsch Clayton V. , Xie Yulong 
Published: December 2007

Abstract
Multiple realizations of facies, porosity, and permeability are used for better representation of reservoir heterogeneity for more accurate performance forecasting and uncertainty assessment. These geostatistical realizations must reproduce all available data to be reliable. The available well, seismic, and production data are at different scales and must be linked to the reservoir modeling scale. The most common geostatistical simulation algorithms call for a Gaussian or normal transformation. It is not possible to merge the data types after this non-linear transformation. This has led to development of "Direct" approaches for simulation and data integration.
Considering the variables without transformation ensures reproduction of the different data and the prescribed covariance or variogram model; however, until now, the resulting global histogram of the simulated realizations is not reproduced. The problem is that there is no theory that specifies the shape of the conditional distributions. The mean and variance are determined from the well-known normal or simple kriging equations; however, theory has not existed to specify the shape of the conditional distributions. A number of ad-hoc solutions have been proposed, but they violate the data and artificially reduce the modeled space of uncertainty.
This paper develops a theory for determination of the required distribution shapes and reproduction of the global histogram. The results have significant theoretical and practical consequences. Data from multiple sources and scales can be directly reproduced in reservoir models with no need for transformation. There is no need for ad-hoc post-processing transformation or correction schemes. Several applications with synthetic data are shown to illustrate the technique.
A Joint Industry Project to Assess Circulating Temperatures in Deepwater Wells
Authors: Ward M. , Granberry V. , Campos G. , Rausis M. , Sledz M. , Weber L. , Guillot D. , Naziri I. , Romero J. 
Published: December 2007

Abstract
Drilling oil wells offshore in water depths exceeding 1000 m is not uncommon in many parts of the world. These conditions present a number of challenges for successfully cementing even the shallowest strings. A major challenge is predicting the temperature to which the cementing fluid(s) will be submitted during and after placement so that laboratory procedures can best simulate the actual situation. What sounds like an easy task for the majority of land wells or offshore wells with shallow water depths turns out to be much more difficult for deepwater wells. This is due in particular to inverse temperature gradients across the sea and convective thermal exchanges between the sea and the fluids in the riser and/or drill pipe.
To better understand the phenomena involved, a series of temperature measurements was made as part of a joint industry project. The primary objective of these measurements was specifically to monitor the cooling effect of the sea through the measurement of the fluid temperature at the mud line depth. All temperature data were measured by a sensor deployed inside the bottomhole assembly while circulating or drilling. This method was selected for its low cost and lack of interference with drilling operations. Data were collected in the Gulf of Mexico, Brazil, Indonesia and West Africa with an average water depth of 1200 m.
A summary of the temperature measurements is presented. Comparison is also made with the predictions of a numerical simulator. The detailed interpretation of these data gathered pinpoints the importance of correctly accounting for the exact temperature profile in the sea as well as the velocity of sea currents versus depth. The outcome of this study helps to define better cement slurry testing procedures for deepwater applications. As a result the technology that is best suited for these specific conditions can be selected on a more rigorous technical basis.
New Applications for 2 1/8" Well Tractor inside 5" Drill Pipe
Authors: Stragiotti Stephen , Skeie Terje , Krüger Christian 
Published: December 2007

Abstract
This paper describes the use of Well Tractor® technology to convey services for recovery of stuck drillpipe in circumstances where conventional methods were considered economically or technically unfeasible.
In the first case, the drillpipe became stuck while running in and circulation was subsequently lost. After 100 jarring cycles were performed it was decided to attempt a fishing operation using the 2 1/8" Well Tractor enabling the retrieval of the radioactive logging source. The retrieval tool was deployed on Well Tractor, which enabled the radioactive source to be successfully recovered from the bottom hole assembly (BHA). The drillpipe was subsequently backed-off using Well Tractor to convey the explosives.
In the second case, drilling losses to the formation were experienced and it was decided to pump lost circulation material. However, during pumping the drillpipe plugged up completely. At the same time flow was recorded on the annulus side and the drilling BOP annular preventer was closed with subsequent pressure build-up below. A 2 1/8" Well Tractor was successfully run inside the DP to first gauge and subsequently punch holes in the drillpipe to open for circulation, thereby allowing pumping of heavy mud and regaining well control.
Assessment of Risk and Uncertainty for Field Developments: Integrating Reservoir and Drilling Expertise
Authors: Irrgang R. , Irrgang H. , Kravis S. , Irrgang S. , Thonhauser G. , Wrightstone A. , Nakagawa E. , Agawani M. , Lollback P. , Gabler T. , Maidla E. 
Published: December 2007

Abstract
This paper describes FieldRisk, a knowledge based drilling system combined with a probabilistic cost and risk assessment software tool for integrated evaluation of field development options. The project uses field data and case studies and includes a database of drilling data from Australia, the Middle East, Europe, and the USA. Knowledge is captured from diverse sources including industry experts, company reports, and published papers using automated information extraction software. Lessons learned in previous field developments can be recycled and applied to similar situations to give a more accurate estimate of costs and risks. Risk, uncertainty and company learning curves are estimated using statistics from past data with allowance for dependencies between events. FieldRisk supports integration of drilling, reservoir and development risks which is a key need for realistic evaluation of offshore field development scenarios. For example, a horizontal well may offer higher production rates, but with a higher risk of hole instability and increased cost of reservoir monitoring and recompletion. Modelling the system in its coupled state can produce a global, life of field optimisation. The tool can use analogous well data from the database for a quick look at costs of proposed new acreage where company offset data may not be available. Multi-target 3D well trajectories can be designed automatically to estimate drilling costs by clicking on a plan view of the field and selecting target depths. Options for drilling and well sequencing, completions, facilities, reservoir risks, reliability of supply and economic considerations can be evaluated in parallel. The tool allows different levels of granularity. Planners can get quick cost estimates, while the asset team can access more detailed information from the knowledge base or view graphically summarised supporting data from similar wells.
Efforts to Persevere a Risk Assessment/Integrity Assurance for its Aged Hydrocarbon Transfer Pipelines
Authors: Kandil Mohamed Essam 
Published: December 2007

Abstract
It is GUPCO's policy to protect against oil pollution and to provide a hazardous free environment for operations within our company.
Maintaining the integrity of oil, gas and water transfer pipelines represents a continuous challenge in GUPCO. It was realized that a pipeline integrity assurance plan could be achieved through the application of a tailored risk assessment program. The key issues of this program which required a reassessment were identified as educating pipeline operators to understand and apply the procedures set out in our management of change (MOC), hazards identification (HAZID), hazards and operability study (HAZOP) and environment impact assessment (EIA) techniques.
As a result, GUPCO has succeeded in making progress towards developing a risk assessment program that provides assurance to help manage pipeline failures, permit adequate environment protection, achieve safe operation and comply with both company and governmental regulations.
Very Thick Crude Emulsions: A Field Case Study of a Unique Crude Production Problem
Authors: Kokal Sunil , Al-Yousif Ali , Meeranpillai N. S. , Al-Awaisi Mohammad 
Published: December 2007

Abstract
This paper presents the results of a unique emulsion and sludge problem in one of the largest offshore oil fields in the world. The problem is related to heavy emulsion sludge deposition in the crude handling facilities. Very viscous emulsions containing 70-90% water were encountered in the offshore facilities where they were plugging up over 50% of the effective separator volume. As there is no bottom water drain at these crude handling facilities, the wet crude forms a very tight, complex emulsion that settles down in the equipment. This problem is anticipated to increase in the future as the water production increases in the field.
A comprehensive study was initiated to diagnose and remedy the problem. Recommendations were made early on to conduct field trials by injecting a demulsifier at the wet crude handling facilities to control the sludge problem. Field trials were conducted at three offshore facilities. Samples were collected before and during demulsifier injection. A new method recently developed for testing emulsions was used to evaluate the removal of the thick emulsions. These field trials were successful and the emulsion/sludge problem has been brought under control. The sludge has been removed and the crude handling facilities are running with minimal demulsifier injection. This paper will describe the research work including a new method to test emulsions, comprehensive results from field trials, and highlight the teamwork between the Research Center and field personnel in successfully solving and controlling an operational problem.
Advanced Interpretation of Venturi Meter Measurements in Multiphase Flow
Authors: Lindsay I , Stimpson B , Corlett A 
Published: December 2007

Abstract
The Venturi meter is commonly used in combination with other sensors for the measurement of gas fraction and water cut as part of a multiphase flow meter system for the measurement of oil, water and gas flowrates. The Venturi differential pressure signals are generally interpreted using empirical corrections to a momentum equation to give a solution for volumetric flowrate.
In this project the use of advanced processing techniques and neural networks have been used to examine the potential improvement in measurement performance which may be obtained from a system incorporating a standard Venturi tube in combination with a gamma densitometer. The data is preprocessed before being applied to a neural network using simple statistical methods combined with some signal processing techniques.
It has been found that this neural network solution performs extremely well when only predicting the gas and liquid phases. Poorer performance was registered when trying to predict all three phases, indicating the need for a water cut sensor.
Yme Marginal Field, 12 km Subsea Gas Lift Experience
Authors: Øverland Alf Midtbø , Ramstad Helge J. 
Published: December 2007

Abstract
Gas lift wells producing from a subsea template placed 12 km away from the processing facilities is known to be very challenging. Long pipelines give large volumes of gas and fluid which may influence each other, causing slugging or pressure variations in production pipelines and pressure fluctuations in the gas lift line. This again creates variations in rates and pressure into the process plant. Gas lift is the preferred artificial lifting method in subsea completed wells, due to the roboustness.The Yme Beta Øst subsea wells were put on production in the summer of 1996. Following a period of natural production the gas lift was started March 97. Immediately after start up of the gas lift heavy slugging in the system, both subsea and in process units was observed. As a result of the slugging the process was frequently shut down due to the pressure and rate variations. To reduce the slugging the wells were choked back, leading to reduced production. The slugging was investigated and the reason for the slugging was found to be in the production pipelines. The varying pipeline pressure influenced the gas lift system in the wells. In order to reduce this, a new gas lift design was carried out and new gas lift valves installed in one of the Yme Beta Øst wells and later both Beta Vest wells.
Interpretational Complexities and Operational Complications Affecting Pressure Transient Analysis in Zuluf Field, Saudi Arabia
Authors: Al-Ghamdi Abdulla H. , Al-Zayer Rayed M. , Al-Samin Isa A. , Al-Gattan Abdulaziz A. 
Published: December 2007

Abstract
The study of pressure transient testing in Zuluf field was initially undertaken to estimate important well and reservoir flow parameters and characterize heterogeneities in the Khafji reservoir. However, during the course of interpretation, numerous engineering complexities were encountered due to the nature of well behavior and reservoir petrophysics. Furthermore, many operational complications resulted in low quality data that negatively influenced the accuracy of the analysis. Interpretational difficulties were caused by complexity in determining net reservoir thickness and wide variation in fluid PVT properties. Operational complications, on the other hand, were caused by wellbore phenomena such as gas slugging, gas humping and phase segregation that affected the accuracy of rate measurement and led to the masking of the actual reservoir response.
These difficulties encountered have led us to take a global diagnostic perspective at the overall well testing practices in Zuluf field with the aim of identifying their causes in order to take the appropriate remedial actions. In light of the outcome of this study, recommendations are made to improve quality of test data by modifying current testing procedure and/or suggesting new alternatives1. Engineering recommendations are also presented in order to standardize the selection of net pay thickness and facilitate the well test interpretation process. This paper highlights findings, results and recommendations of pressure transient analysis study that was conducted in Zuluf field.
Mississippi Canyon 348: Some Reservoir Engineering Considerations Regarding Development of a Deepwater Biogenic Gas Accumulation
Authors: Edman J. D. , Jameson E. W. , Perkins T. M. , Guthrie G. E. 
Published: December 2007

Abstract
Mississippi Canyon 348 (Camden Hills) is a recently discovered biogenic gas field in the deep-water (7200 ft) Gulf of Mexico. The gas in this field is stratigraphically and structurally trapped in a multi-story, distal turbidite channel sand complex. Although considerable work is published on biogenic gas that has been generated and trapped in shelf and deltaic depositional systems, little is understood about biogenic gas accumulations in distal, deep-water, low net sand depositional settings such as this. Given the water depth, a number of economic concerns regarding the reservoir arose during evaluation of the development and delineation wells. First, there was concern about the possible presence of wax and condensate in the reservoir gas. Detailed monitoring of the synthetic drilling mud used in the wells in conjunction with rigorous gas chromatographic analysis of the drilling mud and reservoir hydrocarbons revealed that both condensate and wax are associated with the biogenic gas.
Another engineering and economic concern in this low net sand system was the possibility of reservoir compartmentalization. Geochemical analyses of the methane revealed it to be very uniform and homogenous with respect to both its’ composition and carbon isotopic signature over a vertical interval of at least 4000 ft. However, differences in isotopic signature of immature, indigenous thermogenic gases in discovery well MDT tests demonstrated vertical compartmentalization of the various sands. Later, in the delineation well, similar gas analyses showed the main reservoir sand to be in fluid communication laterally. Early recognition of compartmentalization and the presence of wax and condensate in the reservoirs enabled Marathon to factor these considerations into the field development economics.
An Integrated Pipe Network Model for Simulation of Highly Fractured Reservoirs
Authors: Zhan Lang , Ershaghi Iraj 
Published: December 2007

Abstract
The Monterey Formation, a very prolific reservoir rock, exhibits unique fracture structures where fault zones and other highly brecciated intervals serve as large conduits for fluid movement. Modeling of a network for effective tracking of oil-water contact and rapid subsidence of the invaded water requires new thinking on the modeling process. In this work, we propose a novel integrated pipe-network model (PNM) for simulation of highly fractured reservoirs. It consists of constructing a regular or irregular pipe-network in 2D or 3D space according to major fracture distribution and orientation in reservoirs. Pipe network is the channel for fluid flow, where Darcy's law is applied directly. Micro-fractures and possible matrix in the formation serve as reservoir storage elements at pipe network junctions, at which mass balances are established. The major benefits of the new technique are simplicity in mathematical formulation and superior ability to adapt to fracture distributions. An example is included to compare the result of the proposed pipe network simulator with that of a traditional dual porosity simulator.