bluuebunny/crossref_metadata_2025_split huggingface dataset:
Pressure Behavior of Compartmentalized Reservoirs
Authors: Stewart G. , Whaballa A. E. 
Published: December 2007

ABSTRACT
The single phase material balance equations are derived for a complex reservoir comprised of an arbitrary configuration of rectangular compartments separated by partially communicating barriers. A system of linear ordinary differential and algebraic equations results which can be solved analytically by the methods of state space control theory. The concepts of boundary pressure time delay and desuperposition are introduced which allow the material balance equations to predict well bottom-hole pressures over all flow regimes (transient, late transient and semi-steady-state). Analytical methods allow the history-matching problem to be carried out very rapidly. Four prototype compartmentalised reservoirs are examined - an idealised cellular system comprising a series of identical cells, a two cell system where the supporting cell is very large, a stacked channel realisation and an aeolian dune sand realisation. The pressure response (drawdown and buildup) of these compartmentalised systems is analysed in detail showing how well testing - particularly extended drawdown and building testing - can be used in the identification of geological structure. A new method of pressure extrapolation based on exponential approach to an asymptotic value is shown to have a strong theoretical justification.
Interference Testing of Finite Conductivity Hydraulically Fractured Wells
Authors: Meehan D. N. , Horne R. N. , Ramey H. J. 
Published: December 2007

Abstract
This paper presents techniques for the design and analysis of interference tests when both the active and observation well are intercepted by hydraulic fractures. These techniques are based on new mathematical solutions. The solution is general for any values of dimensionless fracture conductivity including infinite conductivity. The solution is presented in Laplace space; fracture skin, wellbore storage, naturally fissured matrix behavior, etc. are readily included. Any rate or pressure schedule at the active well can be analyzed.
Compass orientation of the wells’ hydraulic fractures can be determined from such an interference test. Relative fracture lengths, conductivities, and azimuth significantly affect well performance. Reservoir heterogeneities may significantly alter interference response. The value of knowing hydraulic fracture azimuth can also be determined. Performance of a hydraulically fractured well near a large natural fracture or another hydraulically fractured well is also forecast. Values of fracture conductivity and fracture length for each fracture can not be determined uniquely from the interference response and must be determined seperately.
Determination of Front Locations in a Multilayer Composite Reservoir
Authors: Anbarci K. , Grader A. S. , Ertekin T. 
Published: December 2007

ABSTRACT
A pressure transient interpretation method for multi-layer composite reservoirs with or without crossflow is presented. The proposed solution includes wellbore skins and storage effects and it is applicable to radial systems with either an infinite outer boundary, a constant pressure outer boundary or a closed outer boundary. Flood fronts in the layers may be located at different positions away from the well.
The detection of reservoir properties and the location of the fronts in the different layers plays an important role in the design and operation of secondary and tertiary recovery processes. The proposed new model addresses the need for an interpretation technique that provides the ability to monitor the location of flood fronts via pressure transient analysis.
The mathematical model is posed with the diffusivity equations for each layer and each fluid zone behind and ahead of the fronts. The boundary conditions at the interfaces can be with or without crossflow. The analytical solution is obtained using Laplace transformation. The new model is successfully tested with respect to four special cases presented in the literature. The sensitivity of the model to reservoir properties is also discussed.
New Pressure Functions for Well Test Analysis
Authors: Onur M. , Peres A. M. M. , Reynolds A. C. 
Published: December 2007

ABSTRACT
In recent years, the pressure derivative has become a highly popular method for analyzing well test data. The main disadvantage of the pressure derivative is that one must construct derivative data by numerical differentiation of measured pressure data. The resulting pressure derivative data is often noisy and difficult to interpret. While various "smoothing techniques" have been used to reduce the noise in pressure data, there exists some concern that the smoothing procedures may alter the basic character of the data. In this work, we present new pressure functions based on the moving or cumulative average of pressure and its first and second derivatives. Using the average value of the pressure derivative is advantageous in that corresponding field data is much smoother than the standard pressure derivative data. It is shown that various combinations of these functions can be used to construct new type curves and to identify proper semilog straight lines.
Zuidwal: A Gas Field Development With Horizontal Wells
Authors: Celier G. C. M. R. , Jouault P. , de Montigny O. A. M. C. 
Published: December 2007

ABSTRACT
Zuidwal is probably the first gas field development with horizontal wells. Originally, a development with fifteen conventional deviated wells was planned. Three horizontal wells have been drilled instead of six deviated conventional wells.
The field is a classical structural trap situated at a depth of 1900 m., with sandstone reservoirs of 100 m. thickness subdivided into several layers, two of which have excellent reservoir characteristics.
The main motivation to drill the wells horizontally is given by the conventional analysis of pressure drop in the reservoir:
– On a deviated well the non Darcian term of the pressure drop due to the gas velocity in the vicinity of the well accounts for an important part of the total pressure drop.
In a horizontal well this term is highly reduced and its productivity is much less affected by its rate.
As a result, horizontal wells will produce twice as much as the equivalent deviated well at only 20% additional cost.
The pattern of the wells consists of two horizontal sections of 100 to 200 m., drilled in the two good layers, joined together by a more and less deviated section. This profile must increase the drainage of these units and minimize eventual water coning.
Three horizontal wells have been drilled using the well-known technology of drilling and logging. The first one was completed in April 1988 and has been in production since August 1988. The two others, drilled in sequence, have been in production since March 1989.
The total lengths of subhorizontal sections of the three wells are 650 m., 540 m. and 610 m., respectively.
The first results of the wells show that the wells perform better than expected.
The main purpose of this paper is to present a review of the well behaviour (well testing, production logging, production history) in order to give useful background on horizontal wells in a gas field.
Estimation of Water and Oil Relative Permeabilities From Pressure Transient Analysis of Water Injection Well Data
Authors: Nanba T. , Horne R. N. 
Published: December 2007

ABSTRACT
This paper presents an interpretation methodology to estimate water and oil relative permeabilities from pressure transient analysis of water injection well data.
This study has been carried out in three related parts. In the first part, mathematical equations for injection, fall off and variable-rate injection solutions are derived based on the multicomposite and stepwise multicomposite systems.
In the second part, the effect of water and oil relative permeabilities was investigated using the mathematical models. The investigation showed that the characteristics of the relative permeabilities are reflected distinctly in the transient part between the early and late time ranges.
In the last part, the inverse problem of estimation of water and oil relative permeabilities from pressure transient data was discussed using the proposed interpretation system, which consisted of the multicomposite model and an improved nonlinear regression algorithm. The study showed that the power-law relative permeability curves can be determined uniquely from pressure falloff data. Interpretation of field examples supported the practicality of the developed approach.
Applications of Emerging Well Testing Technology in South Texas Gas Reservoirs
Authors: Juranek T. A. , Pearcy M. S. 
Published: December 2007

ABSTRACT
An emerging well testing technique, compressive IMPULSE Testing*, has been evaluated in tight, geopressured gas sands in South Texas. The technique relies on evaluating a reservoir's response to underbalanced perforating in a closed system. Bottomhole pressure is measured and analyzed to estimate reservoir pressure, permeability, and completion skin. Determining permeability, a critical stimulation design parameter, from conventional transient pressure analysis is often impossible or unreliable in these low productivity sands.
Results from several case histories were used to evaluate the reliability of compressive IMPULSE Testing. Other techniques such as conventional transient pressure analysis were used to validate these results. In the proper application, reservoir parameters can be obtained quickly and cost effectively using compressive IMPULSE Testing. Specific cases were chosen to demonstrate important operational considerations and limitations of the technique.
The Range of Application of Reservoir Monitoring
Authors: Breitenbach E. A. , King G. A. , Dunlop K. N. B. 
Published: December 2007

ABSTRACT
Reservoir monitoring is a new and emerging technology. It is the application of multiple surveys of reflection seismic integrated with reservoir description and reservoir simulation to track the movement of fluid Saturations in a reservoir.
Reservoir monitoring includes both the measurement of the past and current location of fluids and the prediction of how the fluids will move in the future. This breakthrough in technology is possible through the integration of several disciplines and the focus of each of these disciplines on the reservoir being monitored. Accurate monitoring of the interwell position and movement of fluids in a producing hydrocarbon reservoir can yield major economic benefits through, for example: avoidance of premature breakthrough, optimal placement of infill wells by accurately defining areas of high hydrocarbon saturation, measurement of cone development before coning into a producing well occurs, and other similar improvements in field development.
Seismic response to original fluid contacts has been observed in many fields and reported previously. Recent field experiments, based upon past research, has further shown that a differential technique using repeated seismic surveys, reservoir description, and reservoir simulation is capable of discerning moving oil-water fronts in a reservoir.1 Due to their experimental nature, these field studies have necessarily been conducted under almost ideal conditions for shallow, well defined reservoirs.
In this paper we address the concept of reservoir monitoring and how it is performed. In addition, we address several of the technical issues controlling the success of this technology when applied to the complex reservoirs found in practice and explore the economic justification for applying the technology.
It is concluded that many more reservoirs are potential candidates for reservoir monitoring than previously predicted.
It is further concluded that reservoir monitoring provides a substantial economic return. Guidelines are presented for the range of reservoirs which might benefit from reservoir monitoring.
Petroleum Engineering Manpower Supply Remains Low
Authors: Bourgoyne A. T. , Ghalambor A. 
Published: December 2007

Abstract
The purpose of this paper is to report the results of the Supply Survey conducted annually by the SPE Manpower Committee. The 1988-89 academic year survey was sent to educators from the 30 U.S. schools listed in the Petroleum Engineering and Technology Schools book published by SPE. Twenty-five of these schools offer degree programs in petroleum engineering and five offer options in petroleum engineering within another engineering degree program. Nineteen of the 30 schools, which accounts for about 86% of the U.S. enrollment responded to the survey.
The survey asks each school to report the number of graduates during the 1988-89 academic year at the B.S., M.S., and Ph.D. levels. The number of non-citizens included in these graduates and the number seeking employment in the U.S. job market are also reported. For those graduates who have reported to their school that they have found employment, the type of employer is requested. The following six employer categories are used:
Engineering Salary Trends in the Petroleum Industry
Authors: Lancaster D. E. , Brown D. C. 
Published: December 2007

ABSTRACT
Results of the October 1988 SPE Member Salary Survey indicate an increase of about 4 to 5% in salaries received by SPE Member over salaries reported in October 1987. Results of the 1989 SPE Starting Salary Survey reflect an increase in starting salaries accepted by B.S. graduates in petroleum engineering to $2,900/month. This figure is up 5.5% from a year ago and is the largest increase in starting salaries since 1982.
Emergency Preparedness Training on Offshore Installations
Authors: Brooks K. C. 
Published: December 2007

ABSTRACT
In light of recent accidents offshore, training in Emergency Procedures onboard Offshore Installations continues to receive major focus.
Just recently, the United States Coast Guard issued regulations regarding Emergency Evacuation Plans for Manned OCS Facilities. The current regulations regarding licensing of key personnel on Mobile Offshore Drilling Units (MODUS) is also focusing on the level of training supervisory personnel have in the way of Survival Craft, Stability, Firefighting and Well Control.
This paper will detail the elements of a course called "Emergency Preparedness Training" and the process of how it is conducted onboard Offshore Installations. The initial concept was developed jointly by Reading & Bates and a major oil company in an effort to heighten the awareness that an emergency can occur at any time and that response time is critical. Since the initial conception of this course, some changes have been made but the goals of the course have remained the same. These goals are as follows: Define the Rig Specific Emergency Organization of the Installation.Emphasize the need for realistic drills and show the importance of working through scenarios prior to an Emergency.Conduct major compartment surveys to assist personnel onboard learn how to fight compartment emergencies with available systems and equipment which are rig specific.Understand the capabilities and limitations of emergency equipment onboard and understand what type of back-up equipment is available should problems occur to first line defenses.
The course consists of approximately eight hours (two hours each day). Appropriate videos, class exercises, lecture, a workbook supplied by Exxon Production Research Company and "hands on" training is emphasized in the course.
Rigsite Well Control Training Pays Off
Authors: Stone M. D. 
Published: December 2007

ABSTRACT
The need for effective training of rig personnel in kick detection and well control is widely accepted. However, while many supervisors and toolpushers receive MMS-Certified training of this type, a need exists for training drillers and roughnecks that are involved primarily in turnkey drilling operations on small and medium size land rigs.
These crews are the first line of defense against blowouts. They are constantly in the best position to observe the signs of impending trouble. Therefore, if possible, training programs should meet their needs at their rig site.
A customized, semi-annual, rig site training program was developed in conjuction with the University of Houston at Victoria to provide this training. A preliminary discussion of this program was presented in 1986 in the Drilling Contractor magazine.
The program has been successful and has been premanently retained. This paper will expand on details of the program, describe the introduction of computers for training purposes, and present results of how several kicks have since been routinely handled.
Case History Analyses of Shallow Gas Blowouts
Authors: Adams N. J. , Kuhlman L. G. 
Published: December 2007

ABSTRACT
Blowouts have different characteristics for each situation that require a case-by-case analysis to develop the most appropriate control techniques. Shallow gas blowouts, which are the most common type of blowout, follow the same rule requiring a diagnosis for each case.
However, experiences gained from working on shallow gas blowouts during recent years and a study of other shallow events have shown important similarities in causes and probable results. If applied properly, these similarities can be used to avoid shallow gas blowouts or develop appropriate response plans.
Specifically, our work has shown that many shallow gas blowouts have some relationship to the cementing operations. Also, the paper discusses the details of several case histories (without specific references to the operator or the locale). Since most shallow gas kicks result in a blowout, an additional objective of the paper is to present emergency response procedures for personnel and rig safety. Information is provided which includes drilling procedures, equipment selection guidelines, response of various types of rigs in shallow gas blowouts and a discussion on nser/riserless drilling.
Early Automatic Detection of Drillstring Washouts Reduces the Number of Fishing Jobs
Authors: McCann D. P. , Arnold M. , Burgess T. M. , Curwen S. C. 
Published: December 2007

ABSTRACT
Rapid detection of unexpected drilling events requires monitoring of drilling parameters. The introduction of a computerised monitoring system has led to the development of displays and intelligent alarms designed to help drilling personnel detect and observe events before they would normally be apparent. This paper describes an automated system which detects the early stages of drillstring washouts. Field results demonstrate the effectiveness of this intelligent alarm. Early detection allows the driller to react before failure of the drillstring results in expensive fishing operations.
Successful Deep Liner Cementing in South Texas
Authors: Rae P. , Roemer R. , Kirksey J. 
Published: December 2007

ABSTRACT
In parts of South Texas, the cementing of long drilling and production liners has long been one of the most challenging aspects of well completion. High formation pressures require mud and cement weights that approach the equivalent fracture gradient of the exposed open hole interval. Very low pump rates and excessively long job times have been common due to the constraints imposed by tight annular clearances and the use of heavy, viscous cement slurries.
Another problem associated with these wells is the temperature gradient in this area. Geothermal gradients of 2 deg.F / 100 ft. create large temperature differentials from liner top to bottom, even with liners of only moderate length. Consequently, developing TOL compressive strength and adequate seal at the liner lap has been difficult with the cement retarder concentrations necessary for bottom hole conditions.
Positive and/or negative differential pressure tests are normally used to evaluate these jobs and, in many cases, results have been poor. Since these wells are subjected to hydraulic fracturing upon completion, the integrity of the cement sheath is essential and squeeze work must often be performed to achieve good zonal isolation.
A new design approach has significantly reduced the problems associated with cementing these wells. This approach centres on the careful selection of spacers and the use of highperformance cement slurries. Desirable properties of the latter include very low fluid-loss and exceptional fluidity (low rheology) without development of free water or sedimentation.
Early compressive strengths of these systems are also superior to those of the systems used historically in this area. Case histories from several wells are used to demonstrate the success of this approach.
A Mechanical Stability Log
Authors: Bruce S. 
Published: December 2007

Abstract
The mud weight at which lost circulation occurs depends critically on hole deviation. Similarly, collapse of a high angle well may occur with a mud weight which would provide adequate support in a vertical hole. For this reason, a Mechanical Stability Log (MSL)1 has been developed which, for a given well plan, calculates the range of mud weights which could be used for drilling that well without causing lost circulation or hole instability problems (eg sloughing or caving). It must be noted that chemical effects are not considered: that is, lost circulation or hole instability problems are assumed to have purely mechanical origins.
The MSL uses wireline logs obtained in wells drilled in the vicinity of the planned well as input data. Ideally, density, gamma ray, compressional sonic and shear sonic logs are used. If all of these are not available estimates of "safe" mud weight can still be obtained although with less reliability.
A Full-Scale Wellbore Friction Simulator
Authors: Quigley M. S. , Dzialowski A. K. , Zamora M. 
Published: December 2007

ABSTRACT
An operational wellbore friction simulator (WBFS) utilizing full-scale components for measuring drillstring torque and drag in simulated high-angle holes is described. The 15-ft long test section accommodates 8.5-inch (216-mm) to 12.25-inch (311-mm) ID permeable and cased wellbore inserts. Drilling and tripping operations at angles of 45-90° from vertical are simulated by moving a full-scale tool joint along a 4.0- inch (102-mm) diameter drive shaft. Axialvelocity 0-110 ft/min (0-0.559 m/s) and rotational speed 0-165 rpm represent typical field conditions. The wellbore insert can be pressed against the tool joint with a contact force up to 1000 Ibf (4448 N).
The WBFS was used to study effects of six operating factors on friction coefficients of unweighted lignosulfonate mud with and without a lubricant. Simulated cuttings beds were added for half of the tests. Effects of cuttings beds on friction coefficient were unexpected. In WBFStests, cuttings beds composed of crushed coal slag reduced friction coefficient. Results from large-scale WBFS tests with bare wellbore generally agree with results from certain small-scale lubricity tests. The WBFS results clearly show benefits to using top drives which allow rotation while tripping.