bluuebunny/crossref_metadata_2025_split huggingface dataset:
Acquisition of Wireline Formation Test Tool Data from Unconsolidated Turbidite Sediments, Deepwater Gulf of Mexico
Authors: Rollins D. R. , Crabtree P. T. 
Published: December 2007

Abstract
In this paper we discuss our experiences in acquisition of wireline formation test tool (FT) data. During 1984–1991, Shell Offshore Inc’s Deepwater Division has acquired over 1,500 wireline-conveyed formation test tool pressures and 50 FT samples in unconsolidated turbidite sand reservoirs at subsea depths between 10,000 and 20,000 feet. This FT data has been acquired in Gulf of Mexico wells in water depths as deep as 7,500 feet. This data set allows empirical estimates of the probability of success in acquiring sample and pressure information, as well as assessing the probability of the tool becoming stuck in the wellbore. We also include a brief discussion of experience regarding the operational parameters affecting data acquisition. The operational considerations discussed include the design and setup of the tools themselves and the mud systems and well designs used to optimize tool performance.
Our overall success rate in obtaining pressures is approximately 75%. The success rate for sampling is approximately 65%. Many factors combine to influence these success rates. We find that sticking of this tool is a problem in deviated wellbores, regardless of other factors such as overbalance and set time.
Integrating Seismic Data in Reservoir Modeling: The Collocated Cokriging Alternative
Authors: Xu Wenlong , Tran T. T. , Srivastava R. M. , Journel A. G. 
Published: December 2007

AbstractThe two sources of information commonly available for modeling the top of a structure, depth data from wells and geophysical measurements from seismic surveys, are often difficult to integrate. While the well data provide the most accurate measurements of depths there are rarely enough wells to permit an accurate appraisal from well data alone. On the other hand, the seismic data are generally less precise but more abundant. Two geostatistical methods, "external drift" and "collocated cokriging", are proposed to integrate the two sources of information. A case study is used to document the strengths and weaknesses of both approaches for constructing contour maps of the top structure and assessing the uncertainty on such maps through stochastic simulations.
Sucker-Rod Lift in Horizontal Wells in Pearsall Field, Texas
Authors: Cortines J. M. , Hollabaugh G. S. 
Published: December 2007

ABSTRACT
Oryx Energy has been drilling horizontal wells in the Pearsall Field of South Texas since 1985. While many of these wells came in flowing at rates in excess of 1000 BO/D, it soon became apparent that the wells would need to be artificially lifted early in their life in order to maintain high production rates. Lifting these type wells has proven to be very challenging due to fluctuating rates, varying gas/oil ratios, offset interference and gas interference experienced across the field.
As production from these wells declined to rates below 100–200 BBL/D, Oryx started to aggressively pursue lowering the sucker rod pumps into the curved or lateral portion of the hole in order to reduce reservoir pressure and recover additional oil from the highly competitive Austin Chalk formation. This introduced new challenges as Oryx tried to determine the most economical and effective method and material to perform the job.
This paper reviews one operator's experience with sucker rod lift in the Pearsall Field and is based on data from over 150 wells, including over 80 which are pumping from the lateral section or "in the curve". Methods to reduce gas interference, increase pumping efficiency and extend the life of downhole equipment are addressed.
X-Ray CT Observations of Flow Distribution in a Shaped-Charge Perforation
Authors: Halleck P. M. , Atwood D. C. , Black A. D. 
Published: December 2007

Abstract
We have observed the distribution of flow into a perforation under simulated down-hole stress using an X-ray CT technique. Tests were performed in an Aluminum pressure vessel to allow collection of the X-ray data while maintaining confining pressure on the sample throughout the experiment. A Berea Sandstone target was placed under 500 psi confining pressure and perforated with a 6.5-g (explosive weight) perforator using overbalanced conditions. The perforation was cleaned and flow rate measured under radial-flow boundary conditions using odorless mineral spirits. Flow distribution observations consisted of slow injections of an X-ray opaque tracer followed by collection of X-ray CT image data. The advance of the clearly visible tracer flow front after each injection maps profiles of flow impedance along the perforation.
Observed radial flow rates are highest near the tip end of the perforation. This contradicts the conventional idea of uniform-thickness zone of reduced permeability around a perforation. The present observation suggests that damage is greater near the entrance hole and decreases toward the tip of the perforation. The observed profile can be explained by relating the extent and magnitude of permeability reduction to the amplitude and duration of the shock pressure caused by the impact of the shaped charge jet. Near the entrance hole, the rock is penetrated by the leading, high velocity portion of the jet, creating high shock pressures and more extensive damage. This view is also supported by indentation damage measurements reported elsewhere in this session.
Production Enhancement From Topsides Changes at an Offshore Gas Cycling Project
Authors: Miller J. H. 
Published: December 2007

ABSTRACT
This document provides a case history illustrating how debottlenecking one vessel can significantly improve throughput. It also describes some of methods used to cope with the existing vessel while the case for the new, larger vessel was made and while it was under construction.
Vessel sizing theory is not the primary scope of this article, but the basic ideas are noted and enough data is presented to illustrate the problem.
Additional problems in commissioning natural gas liquid pumps to take full advantage of the increased throughput are also discussed.
Review of New API Pump Setting Depth Recommendations
Authors: Hein N. W. , Loudermilk M. D. 
Published: December 2007

Abstract
Proper design and selection of downhole sucker rod pumps are necessary to extend the life and reduce operating costs for this type of artificially lifted well. This paper presents the results of an API task group’s work analyzing the pertinent formulas, failure modes and necessary information needed to determine the theoretical setting depth limits for tubing and insert rod pumps. Burst, collapse, and fatigue considerations have been incorporated into the formulas. Based on these formulas, it will now be possible to consistently compare different manufacturer’s recommendations on setting depths for different sizes, types, and metallurgy of pumps.
Reservoir Monitoring Over a Producing Norwegian Oil Field
Authors: Johnstad S. E. , Dunlop K. N. B. , Uden R. C. 
Published: December 2007

ABSTRACT
A pilot study over Norsk Hydro's Oseberg field was conducted to confirm that it is possible to monitor hydrocarbon fluid movement in this producing reservoir using repeat 3D seismic data and reservoir simulation.
Two 3D surveys were collected about 16 months apart using the same vessel and equipment and processed using identical parameters. It was important to maneuver the monitor survey in 3D space to the base survey to allow for an optimum comparison.
A detailed interpretation of both surveys were made and even intra-Brent events showed a high similarity between interpretations. The stratigraphie parameters of the geologic model and the related petrophysical parameters were used to build an acoustic model of the reservoir. Detail was added by seismic inversion such that the refined geologic model best fitted both the initial geologic model and the seismic data. The refined model was history matched with a reservoir simulator to estimate fluid saturations at dates corresponding to the two seismic surveys, and these saturations were used for comparison with the observed seismic differences.
The comparison showed a seismic anomaly between the two 3D surveys at a position where the Gas Oil Contact was expected to move. This had spatial continuity and extent, of a similar shape to the simulated saturation changes. The seismic data provided evidence of the configurations of fluid fronts between wells, and not directly observable from well data.
Using a Multilayer Reservoir Model To Describe a Hydraulically Fractured, Low-Permeability Shale Reservoir
Authors: Frantz J. H. , Gatens J. M. , Hopkins C. W. 
Published: December 2007

ABSTRACTThis paper summarizes the development and application of a multi-layer reservoir description for the Gas Research Institute (GRI) Comprehensive Study Well 2 (CSW2), which is completed in the Devonian Shales and located in Calhoun Co., WV. We determined that a two-layer reservoir description best describes the complex reservoir and hydraulic fracture system of the CSW2. This reservoir description, determined using a numerical simulator, matched all the data collected, including pre- and post-fracture flow/buildup tests, multi-layer communication tests, individual-layer injection/falloff tests and pre- and post-fracture production data.The results of this study indicate that a multi-layer reservoir description provides better estimates of post-fracture performance compared to a more conventional, single-layer reservoir description. This result also explains previous, optimistic estimates of post-fracture well performance which were based on single-layer interpretations of pre-fracture test data. This paper reviews and discusses briefly the many diagnostic tests performed on the CSW2, but focuses on the history match analysis and results determined with a two-layer reservoir model. The testing and analysis approach presented in this paper can be applied generally to other tight formations.
Case Study of Stevens Sand Horizontal Well
Authors: Marino A. W. , Shultz S. M. 
Published: December 2007

Abstract
The Yowlumne horizontal well was completed in March 1991 at a measured depth of 14,005’ (11,253’ true vertical depth). The 2252’ horizontal lateral developed a thin Stevens Sand interval that could not be economically developed using vertical wells. The increased pay exposure and drainage radius from a horizontal well provided higher rates and reserves, at lower capital and operating costs, than vertical wells. The horizontal well has produced at more than three times the rate of previous vertical wells in this part of the Yowlumne field.
At the time it was completed, the Yowlumne horizontal well was the most ambitious horizontal drilling project undertaken onshore in California. The well is noteworthy because it exploited a thin sandstone oil column in an active waterfiood, and has an effectively cemented completion. This paper provides a comprehensive analysis of the project’s design and results in three areas: reservoir engineering, drilling and completion.
Characterizing the Effects of Heterogeneity on Oil Recovery by Dry Gas Injection
Authors: Newley T. M. J. , Begg S. H. 
Published: December 2007

ABSTRACT
This paper describes a conceptual study to assess the impact of small-scale heterogeneities on the vaporization by lean injected gas of residual oil remaining in a gas cap after gas cap expansion. Two heterogeneous reservoir elements have been considered, one with a rapidly varying distribution of porosity and permeability and the other with a more slowly varying distribution. The flow of lean gas through each element was modelled using a compositional reservoir simulation program.
The study shows that small-scale heterogeneities within a conventional simulation gridblock can have a significant impact on recovery of residual oil by lean gas. For the heterogeneities used in this study, recovery was reduced by up to one third of that obtained by assuming the gridblock has uniform properties.
The study also shows that the effect of small-scale heterogeneities can be accounted for in compositional simulation by treating the fluid in the gridblock as incompletely mixed.
Wired Pipes for a High-Data-Rate MWD System
Authors: Faÿ J. B. , Faÿ Hubert , Couturier Antoine 
Published: December 2007

ABSTRACT
This paper describes a field drilling experiment in a preselected section of a well, performed to test an electric high-data-rate telemetry system.
The system uses wired pipes from the surface to an intermediate position and an electrical cable inside the drill pipes and the bottom hole assembly to complete the transmission link. Data are transmitted up from the downhole sensor package to the surface computer unit. The process enables continuous transmission of downhole data while drilling or not, at a sampling rate for instance of 360 times per second of four drilling parameters among the variables to be collected.
The field results indicate that this telemetry system is adaptable, reliable and able to transmit numerous and accurate data for hours.
The process should not be considered as a competitor with commercial MWD* systems, but, at a high rate and with greates accuracy, it enables an analysis to be made of downhole drilling variables such as drill string vibrations, actual environmental conditions or dynamic bit behavior.
The Selection of Downhole Annulus Systems for the Piper, Claymore, and Saltire Fields
Authors: Ward R. G. H. , Humphreys A. T. , Steele J. A. 
Published: December 2007

ABSTRACT
The types of well that can benefit from downhole annulus safety systems (DBASS) are discussed. Platform gas lifted wells are treated in more detail because this technology is particularly appropriate to them.
The DHASS completion equipment that was available when Elf Enterprise Caledonia Ltd.(formerly Occidental Petroleum Caledonia Ltd.) first investigated its use is presented. The drawbacks of this equipment and the developments that have taken place since then due to cooperation between users and suppliers are discussed in relation to their desired features.
The types of equipment that have been selected by Elf Enterprise for its existing and new North Sea fields and some early operating history are discussed. Recommendations for additional work to further develop the systems are made.
Experience with Slimhole Gravel Packs
Authors: Gollob K. W. 
Published: December 2007

Abstract
This paper presents a case history of a slim hole gravel packing operation and completion. The gravel/water pack was carried out in a domestic oil well of OMV, Austria in the oil & gas province of the Vienna basin.
In the past, slim hole well completions being not common have kept most of the production & service engineers from putting any effort to design an inside casing gravel pack for slim holes to overcome the problem of sand production from unconsolidated sand formations.
With our experience, OMV is able to produce oil and gas from slim holes. Production history of our gravel- packed slim hole wells shows, that a proper design and a good on-site job execution made it possible to install successfully an inside casing gravel pack.
The gravel pack work string had to be redesigned and adapted for being applicable to slim hole conditions.
It is to be noted that the design and the manufacturing of all desired equipment was done inhouse using entirely OMV 's own resources without any outside help.
Drilling slim holes through unconsolidated hydrocarbon bearing formations is no more a disadvantage for producing these reservoirs. Inside casing gravel packing to prevent moveable sand from flowing can be successfully installed in slim hole sections.
An Adaptive Telemetry System for Hostile Environment Well Logging
Authors: Gardner W. R. , Goodman K. R. 
Published: December 2007

ABSTRACT
The operation of hostile environment logging tools at temperatures up to 250° C stresses not only the tools, it also places severe demands upon the wireline telemetry due to the wide variations in the logging cable transmission characteristics. A robust adaptive wireline telemetry system for use in hostile environments has been developed that combines sophisticated digital communication methods with modern Digital-Signal-Processing (DSP) techniques. The downhole telemetry transmitter outputs a multilevel signal. The uphole receiver includes an adaptive transversal-filter equalizer (TFE) that is continually optimized to correct for changing signal distortion. The system was designed to operate robustly at high data rates over the temperature range of 0 to 250° C.
Optimising Field Design and Operational Requirements by Integrated Reliability and Maintenance Analysis
Authors: Ostebo Runar , Nerhus Olav , Heggland John 
Published: December 2007

ABSTRACT
This paper outlines a toolkit for integrated availability and maintenance analysis of complex offshore field installations. The potential savings in capital and operating expenditures can be large by implementing effective and systematic analysis methods. This paper focuses especially on implications on maintenance costs and costs associated with production loss. Cost-effective availability performance of the platform requires therefore consideration to reliability performance, maintainability performance and maintenance support performance. The nature of these methods implies application from early field planning into operational stages of a field development.
Handling of Produced Water: Looking to the Future
Authors: Georgie W. J. , Bryne K. H. , Kjaerland Gunnar 
Published: December 2007

ABSTRACT
An assessment of the produced water handling facilities has been determined on three offshore platforms, under different operational modes. Specific drawbacks have been defined for the oil removal equipment, caused by the methods, by which the produced water, drain water and fluids from the drilling operation are separated and processed offshore.
An integrated part in the handling problem of produced water in the North Sea, is the difficulty in characterisation of the water and determining the long term water production profile, in the early phase of the field development. By underestimating the handling aspects and volume of produced water, as well as the lack of understanding of the water chemistry, the processing of produced water will be the bottle neck in maintaining the oil production. This is caused by the difficulty in meeting the capacity demand and oil content in the discharged water. However, this problem may easily be overcome by establishing good understanding of fluid chemistry.
This paper will address issues related to improvements in the design criteria of handling produced water and in the selection of suitable equipment in treating produced water on platforms in the North Sea or elsewhere.
In addition, issues regarding the environmental and toxicity aspects of produced water have been assessed, as part of a long term evaluation programme of produced water. It was determined, that although certain chemicals are added to the produced fluid in order to control scale and corrosion, the toxicity of produced water is not necessarily influenced significantly by such chemicals.
As part of the long term environmental objectives in handling produced water, the re-injection of produced water has been assessed. The advantages and disadvantages of such an approach will be addressed.
Possibilities for Reduction of Emissions—in Particular the Greenhouse Gases CO2 and CH4—in the Oil and Gas Industry
Authors: Müssig Siegfried 
Published: December 2007

Abstract
Stock-taking of CO2 and CH4 emissions from the energy sources natural gas and crude oil from origin to final use having been established, possibilities for reducing these greenhouse gases have been evaluated.
Combined cycle processes, heat pumps, fuel cells, etc. have been studied as measures to increase the efficiency of combustion processes. The use of CO2-free energy sources as well as the logistics and the disposal of CO2 in depleted reservoirs or in the oceans have been considered.
The introduction of hydrogen as an additive to natural gas has been considered.
The possibilities of reduction of methane emissions are demonstrated for high-pressure gas transmission lines, dehydration units and low-pressure flowlines including burners. The possibilities of reduction of NOx, CO and UHC emissions in domestic and industrial use are also shown.
It is shown that all processes considered increase combustion efficiency and also offer possibilities for reductions in emissions of greenhouse gases. Fuel cells also indicate a high potential for the future. Special techniques which are currently being introduced in the gas and oil industry are also effective in reducing NOx and CO emissions from combustion engines and burners.
Solar energy, power generation by wind force and other CO2-free energy sources are not recommended for the gas and oil industry; this is left to public power generation. The disposal of CO2 in depleted reservoirs or oceans appears possible, but this is neither an effective method nor an easy to handle procedure.
Reduction in methane emission is relatively easy to achieve.
The developed concepts for the reduction in emission of greenhouse gases and other pollutants can be applied in all sectors of the gas and oil industry. They are regarded as technically sound. An improvement in the economics of these measures is still desirable.
Quality Assurance/Quality Control for the Sake of Hole Safety
Authors: Parigot Philippe 
Published: December 2007

ABSTRACT
PERSONNEL, RIG EQUIPMENT and ENVIRONMENTAL safety are topics responsibly addressed today by all Companies involved in the oil industry. A strong and common commitment leads to a continuous improvement which is supported by a costly effort in research and reinforced by detailed procedures and regulations. On the other hand, HOLE safety seems to have been given a lower priority. A general consensus that makes a fully comprehensive effort in this domain and that accepts to pay the corresponding cost, does not seem to exist.
Driller's procedures are firmly described and strictly respected. Mud Logger, Mud Engineer, etc… must accept the same constraints supported by thorough QA/QC on the corresponding procedures.
This paper presents a variety of true field cases which highlight the missing link in the general safety concept.
The Innes Field: Complete History of a Marginal Subsea Development
Authors: Harries P. G. , Smith Christopher , Compton S. E. 
Published: December 2007

Abstract
The Innes field, lying in Block 30/24 of the UK North Sea was discovered in 1983. After a single appraisal well had been drilled and an extended production test on the initial discovery well, estimated reserves were uncertain but low. Economic development of the field was achieved in two phases, using low cost proven technology in an innovative manner. The first phase involved the use of a floating production facility. In the second phase the economic field life was extended by the tieback and production of the Innes field as a remote subsea satellite, 14 km from the floating production facilities at the Argyll Field. The Innes field produced in this mode until cessation of production in December 1990.
Material balance modelling confirms the drive mechanism as solution gas drive, supported by minimal aquifer influx, with the migration of mobile gas to form a secondary gas cap. Total recovery by the end of field life has been 5.8 MMSTB, equating to a recovery factor of approximately 30 %.