bluuebunny/crossref_metadata_2025_split huggingface dataset:
Advanced Seismic Data Interpretation for Carbonate Targets Based on Optimised Processing Techniques
Authors: Fischer Klaus , Moller Ulrich , Marschall Roland 
Published: December 2007

Advanced Seismic Data Interpretation for Carbonate Targets Based on Optimised Processing Techniques.

Abstract
The Shuaiba Fm. represents one of the most prolific hydrocarbon reservoirs in Abu Dhabi. The remaining potential is supposed to be related to subtle structural and stratigraphic traps. New developments in exploration geophysics like prestack depth migration integrating processing and interpretation form a powerful tool for improved development of existing oil fields and for identification of new oil fields.
In general the processing comprises three phases (depending on the local validity/violation of the zero-offset (zo)-condition, i. e. to which extent does the DMO-stack represent a zo - volume):
Phase A: Standard processing sequence up to final DMO stack and migration including calibration using elastic instead of plane-wave synthetic seismogram. The interpretation team generates a first macro model of the velocity field.
Phase B: Poststack depth-domain
The velocity field is checked and updated using the wavefront method. The new macro model forms the basis for poststack depth migration, which is reinterpreted by the interpretation team in order to confirm / update the reflector geometry and to generate the final macro model required for
– Phase C: Prestack depth-domain.
The prestack depth migration is subject to final interpretation and - due to the irregular surface of the Shuaiba Fm. - should form the basis for AVO. Further steps are L-l- deconvolution followed by Born inversion, which is essential for generation of a high resolution lithological model.
The procedure is presented using a 2D seismic line, which was subject to a detailed interpretation (seismic sequence and facies analysis) of the Shuaiba Fm. The final result is a detailed lithological model which is verified by applying elastic forward modeling ("verification loop's"). The results are to be used as input in reservoir modeling and geostatistical evaluations in order to take into account reservoir heterogeneities being important for prospect evaluation.

Introduction
Geology and Stratigraphy of the Shuaiba Fm in Abu Dhabi. The shallow water carbonates of the Lower Cretaceous Shuaiba Fm (Upper Thamama Group, Aptian) was deposited on a vast shelf covering the eastern Arabian Peninsula. The formation of intrashelf basins resulted in the establishment of facies belts i. e.–shallow water shelf carbonates–a buildup prone belt rimming the intrashelf basin centered in Abu Dhabi and–basinal deposits in the intrashelf basin areas.
The shelf margin buildups - mainly rudist buildups - of the belt rimming the intrashelf basin today form the most prominent hydrocarbon reservoirs (Frost et. al., 1983). The shallow water shelf carbonates however may represent a potential reservoir due to increased porosity resulting from subarea exposure and weathering by meteoric waters during the Bab relative sealevel lowstand.
P. 730
The Accuracy of Cubic Equations of State for Composition Predictions
Authors: Abrishami Y. , Hatamian H. 
Published: December 2007

Abstract
Tuning of the equation of state have proven to be the most successful method for improving the performance of compositional reservoir simulators. The data used for this purpose are normally PVT laboratory measured values of overall fluid composition, densities and viscosities, together with saturation pressure and liquid dropout at the cell conditions. In the simulation of oil recovery processes, where changes in compositions and interphase mass transfer are dominant factors, the tuning should logically be based on matching with measured values of compositions rather than, or in addition to, the aforesaid values. This is even more essential in solvent injection simulations, where the overall composition of the fluid is continuously changing. Existing tuning techniques provide a degree of improvement, however, change of composition in solvent injection requires regression and tuning on the base of composition matches in a multiple contact process. In this work we have developed a computer programme for simulation of multiple contact gas injection process which has been used for reproducing some experimental values on composition in constant composition expansion and multiple gas injection tests. The Peng-Robinson equation of state is examined for matching the measured values.
3-D Seismic Data Acquisition in Offshore Congested Field
Authors: Belaid Kamal 
Published: December 2007

Abstract
This paper describes the techniques and strategy implemented by ADMA-OPCO in acquiring a successful and cost-effective 3-D seismic survey in a highly congested field located offshore Abu Dhabi. The early planning of the survey, the team work, the adequate data QC and the interaction between the three phases of data acquisition, processing and interpretation are highlighted as the key elements which granted the success of this survey. They contributed in achieving the technical objectives and addressing efficiently the logistical issues in a cost-effective manner.
Coiled Tubing Deformation Mechanics: Diametral Growth and Elongation
Authors: Tipton Steven M. 
Published: December 2007

Abstract
Coiled tubing endures unique cyclic stress and strain histories. The loading imposed on pressurized coiled tubing can trigger deformation mechanisms resulting in incremental plastic diametral growth and elongation. This growth occurs in spite of the fact that both the hoop stress and net axial stress from tension are well below the material yield stress. The most dominant factors controlling the deformation behavior of coiled tubing are the bending-straightening cycles associated with the spool and gooseneck. It is the interaction of the bending stresses and strains with those from axial loading and pressure that result in plastic elongation and diametral growth. Severe cyclic plasticity imposed by these events actually changes the structure of the coiled tubing material, causing a corresponding change in mechanical properties. The material properties in a section of coiled tubing along a string are thus dependent upon the localized service loading history.
The operating parameters that control the loading on a section of coiled tubing are discussed in terms of the tubing geometry, the above-surface deployment equipment and the sub-surface environment. With the load history characterized in terms of imposed stresses and strains, mechanisms that lead to diametral growth and elongation are demonstrated from the standpoint of simple material plasticity models. Refined models are described, based on more sophisticated plasticity relations, capable of characterizing transient behavior and multiaxial effects. Implications from these results for depth calculation are discussed.
Coiled Tubing Management System: A Review After two Years in Operation
Authors: Campbell James Andrew 
Published: December 2007

Abstract
This paper reviews a coiled tubing management system that has been in operation for over two years in European and West African operations. Complete tubing records for up to at any one time 20 coiled tubing units and in excess of 100 strings of coiled tubing have been recorded by the system. Data has been taken from the system, covering the total amount of tubing run over the period and has been broken down to show running footage between different pipe sizes, amount of failures and maintenance carried out on coiled tubing.
Corroboration of the fatigue predictions of the system is also discussed, with test results of tubing that had reached its safe working life under the CYCLE system being tested to destruction on a fatigue rig to evaluate the suitability of the fatigue algorithm used.
Hydraulics Design in Coiled Tubing Drilling
Authors: Walton Ian C. , Gu Hongren 
Published: December 2007

Abstract
Key design considerations in coiled tubing drilling are associated with the wellbore hydraulics, which includes drilling fluid types, liquid and gas injection rates, injection method (gas injection down coiled tubing or through parasite string), circulation, downhole and wellhead pressures, cuttings transport, and rate of penetration. This paper presents a design methodology to achieve efficient hole cleaning and maintain a specified under-(or over-) balance, based on the use of a suite of computer programs. Two design programs are used to determine fluid types and injection rates, and a pump schedule is generated. The pump schedule is then used in a transient computer wellbore simulator to verify that all operational requirements are satisfied for the entire drilling operation. During the design stage, the effects of the coiled tubing size, drilling fluid types, injection method, overbalance or underbalance are investigated using the computer programs. Examples are given to illustrate the design process.
Partnering Lessons from a North Sea Experience
Authors: Stapel Gerard , Wilson Rich 
Published: December 2007

Abstract
Well construction and maintenance partnerships have come of age for the Operator, based on their success in the North Sea environment. This paper examines those critical success factors and provides an overview of how the Operator moved from the back to the front of benchmark performance tables through the application of partnering.
The well construction partnerships typically include the Operators well engineering group, the drilling contractor, the Deviation Drilling and MWD contractor, the well testing contractor, the data acquisition contractor and the cementing contractor.
The Operator currently has three partnerships in place. All of these are driven by a commercial engine that rewards ‘best in class’ performance through an independently benchmarked process as well as providing ‘continuous performance-contingent’ contracts that removes termination clauses and regular tendering and puts the power for contract continuity in the hands of the partnership. This commercial environment has provided an incentive for all the partners to make long term investments in the partnership.
It is considered that true alignment of goals has been achieved with a win/win strategy being applied at the wellsite as well as at managerial and organisational levels. The role of other critical success factors such as; leadership, core strategics and rules, integrated team-working, specialised partnering training, an organisation designed to focus on performance and rewards systems are examined. This paper provides a comprehensive review of the key factors leading to significant performance improvement for the Operator and provides a generic checklist for well construction partnering / alliance efforts elsewhere.
Development of the First Commercial Hot Hole MWD System
Authors: Brady J. K. , Galley T. 
Published: December 2007

Abstract
This paper discusses the development of the industry’s first MWD system designed to operate at temperatures to 175°C (347°F), survive to 200°C (392°F), and withstand circulating pressures of 22,500 PSI. It describes the methodology employed which enabled the product to be taken from a technical feasibility study to a field test in less than seven months. The technical constraints which were overcome to achieve the operating specifications of the system while maintaining high reliability will also be described.
Mechanical Stability Analysis from Drilling Data Alone
Authors: Jones John F. , Barree Robert D. 
Published: December 2007

Abstract
An extremely important and often challenging problem associated with drilling inclined wellbores is maintaining mechanical stability. A number of analytical and numerical models are available in the industry, which aid in evaluating the degree of stability expected in a given wellbore. Application of these models requires input of formation rock properties, which are sometimes difficult and costly, or even impossible to obtain Complicating matters, even with the availability and input of these data, the stability models often inaccurately predict the mud weights necessary to maintain the mechanical stability.1–3
A stability analysis was performed to determine the feasibility of drilling a high angle well (63 degrees) from a Gulf of Mexico platform. Due to the lack of core data, the rock strength properties of the shale sections had to be estimated from prior drilling data.
A case study is presented to compare the estimated required mud weights to the actual mud weights needed to drill the high angle well. The procedures used to determine the pore pressure, fracture gradient, overburden and in-situ stress state are also discussed. Both the commercial and in-house software applications used in this analysis are briefly described and evaluated.
In addition, the potential for developing an empirical model to estimate the rock strength properties of shales is examined.
Applications of Pseudo-3D Stress Analysis Programs for Predicting Borehole Collapse and Formation Breakdown
Authors: Ramos G. G. , Polillo Adolfo , Wilton B. 
Published: December 2007

Abstract
In a drilling/production operating environment, wellbore instabilities arise in all three stages of a well’s life span: drilling, stimulation and production phases. The timing and severity of the occurrence of such borehole problems dictate which method of stability analysis should be used. Pseudo-3D codes are plane-strain, non-isotropic subsets of full 3D numerical and analytical codes. Their speed, portability, and ease of use have popularized them among operations engineers. There are numerous versions of pseudo-3D stress analysis, from simple linear-elastic to sophisticated poroelastic-plastic, each with its own advantage that suits a particular wellbore problem. Simple linear elastic codes are re-emerging in popularity because of ease of use and field-calibration schemes.
Field Cases of Horizontal Well Pressure Transient Analysis in West Africa
Authors: Bourgeois Marcel J. , de la Combe Jean-Luc Boutaud , Deboaisne Renaud M. 
Published: December 2007

Abstract
Horizontal well tests are often difficult to interpret because wellbore storage may partly hide the early-time transient, and an underlying aquifer may alter the late-time data. This paper shows how recent advances in interpretation techniques have enabled us to address these problems.
The first field case shows a well test where both downhole flowrate variations and investigation of the aquifer affected the data. PLT flowrate measurements were used to perform Laplace space deconvolution. In this case, the pressure loss due to friction along the drain behaved like a quadratic skin and could be estimated, and linked to an average friction coefficient.
In the second field case, deconvolution showed that friction could be neglected, as is usually done with infinite conductivity solutions[1].
The third field case gave a questionable match with a conventional horizontal well model, as the lower layer displayed a strong angular unconformity, which precluded final stabilization of the derivative. Thus we used Kuchuk’s multilayer horizontal well solution[2] to model this complex geometry. We had to model the change in rock type and anisotropy in the lower sedimentary unit. It enabled us to get a good pressure match on the derivative of the buildups as well as on the cartesian data plot comprising several transients.
Petrophysical Interpretation of a Multispacing 2-MHz MWD Resistivity Tool in Vertical and Horizontal Wells
Authors: Wu Peter T. , Tabanou Jacques R. , Bonner Stephen D. 
Published: December 2007

Abstract
The multiple phase shift and attenuation resistivities from a 2-MHz array resistivity tool provide the log analyst with the measurements needed to resolve complex interpretation problems associated with high relative dip formations typical in horizontal and highly deviated wells. With the support of modeling, productive zones can be located that may otherwise be missed.
In high relative dip formations, the interpretation of multispacing 2-MHz resistivity tools and the comparison with wireline logs are not straightforward. Therefore, it is imperative for the log analyst to understand the unique response characteristics of these measurements in both vertical and horizontal wells. In high relative dip formations, the primary factors that may cause the resistivity curves of different spacings to separate are borehole effects, invasion, bed boundary proximity and anisotropy. With the help of forward modeling codes and inversion algorithms, the log analyst can resolve most of the interpretation ambiguities.
The responses of a 2-MHz array resistivity tool, with five measurement spacings, to the above factors are illustrated and discussed. Traditional rules of thumb based on vertical well must be modified significantly. Productive zones that would be missed by logs made in a vertical well can easily be detected by logs made in a high-angle or horizontal well through the same formation. A comparison of the resistivity responses of a 2-MHz tool in low and high relative dip formations helps explain the differences between logs made in low-angle and high-angle wells.
Measuring Three-Phase Holdups in Horizontal Wellbores Using Pulsed Neutron Instruments
Authors: Trcka Darryl , van den Berg Frans , Manan W.A. , Peeters Max , Mickael Medhat 
Published: December 2007

Abstract
A new method of determining three phase holdups in horizontal wellbores using pulsed neutron tools has been field tested. A two variable, linear algorithm using the measured inelastic carbon/oxygen and near/far ratios is used to determine holdups. The measurement is fully characterized by Monte Carlo modeling. Laboratory data shows the accuracy of the holdup calculation to be approximately 10%. The method produces a continuous borehole image of the volume fractions of the water, oil, and gas in the borehole. Log examples demonstrate the use of the Pulsed Neutron Holdup Imager in horizontal well production logging and in production logging behind tubing.

Introduction
Three phase hold-up data are essential for remedial action in wells that produce unwanted water and gas. The traditional production logging tool suit consisting of temperature, pressure, fluid capacitance, fluid density, spinner flowmeter and gradiomanometer sensors has proven its utility for production monitoring in vertical wells. In horizontal wells, however, the interpretation of the holdup measurements from conventional production logging instrumentation becomes unreliable due to the fluid segregation. Thus, there is a strong motivation for devising an alternate method of measuring holdups with improved accuracy in horizontal wellbores.
Nuclear measurements offer a method for measuring three phase holdups in horizontal wells with increased accuracy. In contrast to the traditional production logging tools which measure at a localized position in the borehole volume, nuclear measurements average over a larger volume and are relatively insensitive to the segregation and layering of the flow components in horizontal boreholes. Additionally, in single or dual string completions, nuclear measurements can measure nuclear responses through the tubing wall and, therefore, image the annular region of the wellbore that is physically inaccessible to direct measurement. Further, the nuclear measurement offers the possibility of imaging the holdups covering the whole borehole, including by-passed flow around slotted liners and screens.
P. 759
Outsourcing Engineering Services – The Business Side of the Business
Authors: Truman R. B. 
Published: December 2007

Abstract
This paper provides the guidelines for identifying, evaluating, and selecting the appropriate type of outsourcing personnel and estimating the costs associated with using these resources. A description of available personnel resources (consulting companies, service companies, contractors and semi-retired) are provided along with their applicability and usefulness to fulfill outsourcing engineering requirements.
Each of these classes of personnel also command a different price in the marketplace. The means of simply estimating these costs is provided. The rationale for these costs are developed and also presented.
The information presented is useful for all petroleum company managers involved with outsourcing engineering services. This information will provide management with the guidelines for selecting a service provider which will fit their needs. The methods presented for estimating costs will assist planning and budgeting of outsourcing expenses.
As oil and gas companies downsize many personnel have become consultants or contract service providers to the petroleum companies. This paper will provide these people with guidelines for positioning themselves in the market. In addition, it also provides a method of determining their true costs.
This paper will not discuss the correct pay for full time employees. It will discuss what a petroleum company should expect to pay and what the service provider should expect to receive based upon the base salary of a full-time employee for the equivalent job within a petroleum company.
Recent Trends in Hydraulic Fracturing
Authors: Wieland D.R. 
Published: December 2007

Abstract
Trends in hydraulic fracturing over the years have closely followed an increased knowledge or better understanding of what occurs in the formation during a fracturing treatment. As more and more knowledge was gained emphasis shifted from materials to horsepower and high injection rates. Recently the shift has been back to materials and more careful planning and engineering of individual treatments.
Improved technology within the past two or three years has led to the development of new, viscous fracturing fluids and more sophisticated computer programs. These developments have greatly improved results of fracturing treatments and have made it possible to successfully stimulate those wells which previously were poor candidates for hydraulic fracturing poor candidates for hydraulic fracturing treatments.
The purpose of this paper is to discuss recent developments in fracture fluids and techniques and the technology involved in their use. Case histories are used to show the improvements in economy, efficiency, and increased production results.

Introduction
Since the introduction Hydraulic fracturing as a stimulation tool in the late 1940's, development trends have closely paralleled each fact learned concerning what actually takes place in a formation during a fracture treatment place in a formation during a fracture treatment In the early days, equipment available was capable of providing injection rates of one to two barrels per minute and screen-outs were common. It was felt that viscous fluids would suspend and transport propping agents better and development emphasis was on fracture fluids. Heavy refined oils became common frac fluids and water-in-oil emulsions, acid-in-oil emulsions, and soap-type oil gels appeared.
Next, fluid loss was recognized and fluid loss agents were introduced. It was discovered that in many cases crude oil could be used as a fracture fluid with these new agents and treating economics apparently improved. The trend to crude oil with fluid loss agents, however, increased the incidence of screen-outs until a relationship between injection rates and screenouts was found. Increased injection rates reduced the probability of a screen-out and equipment was built to provide higher rates.