bluuebunny/crossref_metadata_2025_split huggingface dataset:
Concrete Gravity Substructure for Southern North Sea
Authors: Luedtke R. C. , Woodhead L. , Worrall M. F. 
Published: December 2007

ABSTRACT
Ravenspurn North is a gas field development in the Southern North Sea. A novel feature of the development is the use of a Concrete Gravity Sub Structure (C.G.S.) to support the central gas production and compression facilities. The primary reason for selecting this concept is that it offers a cost advantage over steel jacket options.
Concrete in itself is not novel to the North Sea. Concrete structures have been successfully used in the Northern North Sea, where they have tended to be very large. (100,000 tonnes or more). The Ravenspurn concrete platform weighs less than 30,000 tonnes and consists of a cellular caisson base with three circular concrete towers. Two of the towers support the gas production deck and the third supports the gas compression module.
A significant feature of the Ravenspurn platform is that the integrated production deck weighing 6,300 tonnes will be installed offshore at location using a semi-submersible crane vessel. This feature allows considerable savings to be made in the concrete quantities and the amount/complexity of the mechanical outfitting, with a resulting cost advantage. This saving reduces the size of the platform to such an extent that the concrete Substructure can be totally completed within a dry dock.
This paper describes: -The Field Development Plan, with emphasis on the Central Production Platform.-The feasibility study work which led to selecting Concrete for the substructure.-The foundation considerations.-A description of the C.G.S. and method for building.
The Steipner A Platform: An Efficient Gas and Condensate Installation
Authors: Gudmestad O. T. , Coker J. W. A. 
Published: December 2007

ABSTRACT
The efficient design of the installation for production of Sleipner Øst gas and condensate enabled Statoil to make a breakthrough in selling gas from the Norwegian continental shelf to the European gas market under the Troll gas agreement.
A well defined concept developed by an inter disciplinary group of technical specialists from Statoil in close cooperation with the operation group have laid the grounds for an optimal combination of fabrication and EPC contracts in the detailed design and construction phases.
The technical concept is based upon a realistic compromise between technical and operational requirements with specific emphasis on layout and fabrication aspects and through careful review of required safety and instrumentation needs. Attention has been particularly paid to optimal equipment reserve philosophy to reduce investment costs.
The process design features gas recirculation with accelerated condensate production. The structural design includes a concrete gravity base structure, and an integrated module support frame which incorporates many functions and which could be constructed as two large modules.
Due to use of only 7 modules weighing in the range of 3 - 5000 t, hook-up operations will be minimised to make lifting of the module onto the floating platform inshore the most economic construction method.
The drilling equipment located in the centre of an X-shaped deck with the risers and compressors located about 100 m away from the living quarter provides for an efficient and safe layout. The platform is also an essential part of the gas delivery system under the Troll agreement.
Structural Design in Aluminium: Sources of Technical Information
Authors: Buxton P. G. 
Published: December 2007

ABSTRACT
With increasing interest in weight and cost reduction of offshore structures, the use of aluminium alloy is being seriously considered as an economic structural material. The high cost of the material is balanced by its high strength/ weight ratio compared to steel.
Guidance is given on the background and sources of information related to the United Kingdom Design Codes. Reference is given to Selection of Materials and further Work.
A substantial list of references to standards and publications is given in the Appendix.
Field Development of the Scapa Field: A Marginal North Sea Field
Authors: Chen H. K. 
Published: December 2007

ABSTRACT
The Scapa Field, North Sea was discovered in 197 5. The field is developed with an integrated production/injection subsea template system, tied back to the main Claymore platform. Subsea oil production began in November 1986, only 14 months after Annex 'B' approval. The encouraging results of the extended production test from a deviated platform well and appraisal wells in 1984 and 1985 formed the basis for the field development. The continuous downhole pressure recording, extensive RFT' measurements and other data gathering programmes are essential for successful development of a complex marginal field. The estimate of the recoverable oil has been increased by 25 million barrels (4 million M3). The field development to date owes its success to the combined efforts of a multi-disciplinary team, which resulted in the optimum placement of wells. Although marginal in size the development success to date has resulted in an economically healthy project.
The Veslefrikk Jacket Concept
Authors: Lefranc M. , Austin C. W. , Crowle A. , Brown Aker John , Baerheim M. 
Published: December 2007

ABSTRACT
A new concept for developing oil fields has been prepared by Statoil for the Veslefrikk field in the North Sea.
For this deep- water location (174 m) a combination of a semisubmersible production and quarters unit and a drilling jacket is to be used.
In the effort to reduce the total cost of the project Statoil propose to minimize the steel weight of the jacket and to install it by lifting.
The lifting criteria thus limited the lift weight for the 200 m tall structure to 9800 t which is a challenge for the designers.
Aker Engineering was given the task to further develop the jacket and floater.
A close cooperation of specialists for lay-out; marine operation and structure design led to a jacket design with the following features. –optimization of the equipment weight–rotation of the derrick skid beam and the deck by 45° relative to the jacket.–reduction of the environmental forces by minimizing the size and the number of the structural elements, and systematic use of the shielding effect.–use of a temporary sledge for the load-out and transport conditions.–cast nodes and lifting trunnions–offshore installed tubular insert in the legs and separate deck support frame.
The lift operation is the most critical aspect of the Veslefrikk project. A description of the analysis and the particular requirement of this operation is given.
Finally a description of the installation procedure is presented.
Reservoir Monitoring and Wireline Logging in Subsea Wells
Authors: Lilley I. J. , Douglas A. A. , Muir K. R. , Robinson E. 
Published: December 2007

ABSTRACT
In an effort to minimize capital investment in platform installations there is an increasing trend towards drilling subsea satellite wells, with production tied back to an existing platform. A disadvantage with this type of well is that regular access for maintenance and reservoir monitoring is denied by the high cost of conventional techniques.
This paper, which discusses some new techniques for economic monitoring and maintenance of subsea wells, is divided into two sections.
The first section describes the installation and use of permanent gauges run with the completion in subsea wells. Methods of mounting the pressure gauge in the completion string and transmission of the data to surface are discussed. A field case is reviewed which highlights some of the advantages of continuous reservoir monitoring.
The second section of the paper describes a newly-developed technique for wireline logging in wells completed subsea. The method involves a specially designed lubricator and pressure-control system which can be deployed from a dynamically positioned support vessel. The discussion is focused on the practical aspects of the technique, as well as giving an overview of the types of operations that can be performed.
Hydrogen Stress Corrosion Cracking of High-Strength Steel in Lignosulfonate Mud
Authors: Oberndorfer M. 
Published: December 2007

Abstract
The resistance of high strength steels against stress corrosion cracking in lignosulfonate muds is described in this report. Soluble sulfides contained in LS muds may cause damage under certain circumstances. A failure case in a 7" casing of V 150 quality is reported. Failure analysis demonstrated a typical intercrystalline crack. Basic experiments with tensile samples in LS muds showed the conditions which can lead to a failure. Finally, the results are compared to literature experience in proposed guidelines for the use of high strength materials.
Hydraulic Optimization of PDC Bits by Visualization Methods
Authors: Bisson P. , Choux J. C. , Provo A. 
Published: December 2007

ABSTRACT
The number of ways in which cutters are distributed, and the number of shapes of Polycristalline Diamond Compact (P.D.C.) bits are increasing every day. These bits can be fitted with either nozzles or crowfoot fluid outlets. The fluid will spread around the bit in a more or less complex manner depending on these outlets and on the geometry of the annulus encountered. This fluid distribution will have an influence on the efficiency with which the cuttings are evacuated and on the cooling action on the cutters, i.e. the capability to drill faster and for longer.
The methods by which flow structures can be determined, are high-performance numerical methods and visualization experiments.
This paper describes a testing sequence for flow visualization, which has been developed in the laboratory, plus the necessary equipment.
These tests reveal the hydraulic structures, and those most frequently encountered will be described.
A concrete example showing the application of our studies will be given: the case of bit profile improvement used by one of our subsidiaries on an oil field under development.
The limitations of our experiments, allowing for the tests run and the equipment available, will be discussed, as well as future lines of research.
Experimental Measurement and Modeling of Gas Solubility in Invert Emulsion Drilling Fluids Explains Surface Observations During Kicks
Authors: Swanson B. W. , Gilvary B. , McEwan F. 
Published: December 2007

ABSTRACT
The solubility of methane in an invert emulsion drilling fluid has been measured up to 15000 psi [103.42 MPa] and 350F [177 C]. Resulting data describing the effects of temperature and pressure on mixture density and phase behaviour havebeen incorporated into a computer model to determine wellbore responses at surface and downhole. The model contains algorithms to model the transport of dissolved gas by dispersionand free gas by bubble rise in addition to models for fluid flow. The model is capable of simulating both controlled anduncontrolled kicks in invert emulsion drilling fluids. Gas behaviour in water based drilling fluids can also be evaluated. Surface responses including pit gain, annular flowrate and choke pressures have been simulated.
It has previously been suggested that gas kicks in deep high pressure wells and oil based drilling fluids are more hazardous than in water-based fluids because of the solubilityof hydrocarbon gas in the oil phase of the mud; the gas in solution producing only a fraction of the expected pit gain at surface. However, results from the current model indicate that when a kick is taken in a deep high pressure well the observations of pit gain at surface can be similar for both oil- and water-based muds.
The Role of Downhole Flow and Pressure Measurements in Reservoir Testing
Authors: Joseph J. , Ehlig-Economides C. A. , Kuchuk F. 
Published: December 2007

ABSTRACT
In practice, a reservoir test that is successfully executed according to a specified pragmatic design will provide interpretable results satisfying the test objectives. Usually, there isanoptimal test design among several options which will minimize the cost of the test, without jeopardizing the likelihood that useful interpretations will ensue. Consequently, as numerous testing configurations have been introduced, it has become necessary to develop interpretation procedures which are as straightforward as the conventional techniques while offering a more reliable or refined answer. The use of downhole flow and pressure measurements, or even downhole shut-in devices, are cases in point. With proper design, execution and interpretation, tests which employ these configurations can provide reservoir properties that could be much more difficult to obtain by other means.
One objective of this paper is to present a methodologyfor reservoir test interpretation. This defines the hierarchy and sequence for employment of all analysis techniques, and is intended to be general enough in concept to accomodate any type of test. Field examples are used to illustrate the merits of specific acquisition procedures, and also how the methodology can aid in achieving the test objectives with consistent and coherent analyses.
A Case Study of Casing Failure and Damage Under Artificial Lift Conditions in the Montrose Field
Authors: Andrews I. J. 
Published: December 2007

ABSTRACT
This paper reviews the extensive logging programme carried out since February 1987 in the producing wells of the Montrose Field to identify casing damage. The evaluation of the 9-5/8" (0.244m) casing was required because of several recent cases of casing collapse while electrical submersible pumps were operating.
This was accomplished by running electromagnetic, sonic and mechanical caliper logs to establish casing dimensions. From the results gained, three main problem areas were identified. The first was eccentric tubing/drillpipe wear, the second, general corrosion and "rogue" light weight joints of casing and finally the 9-5/8" (0.244m) casing was found to have buckled in several wells.
Collapse was therefore caused by a combination of large differential pressures imposed by the ESP's which utilize a high set packer for venting gas, underweight casing and casing damage/wear caused by drillpipe.
Analysis of the logs allowed areas of potential collapse to be identified by determining the approximate reduction in casing collapse pressures. Collapse was then averted by extending 7" (0.178m) liner over the danger area, or by changing the operating conditions.
Sound Speed Of Natural Gas
Authors: Savidge Jeffrey L. , Starling Kenneth E. , Mcfall Richard L. 
Published: December 2007

Summary
We present a highly accurate correlation for ideal gas properties and a vapor phase equation of state for natural gas and related mixtures. The equations are used to compute sound speed. Results from the new methods are compared to recent sound speed measurements on pure methane and simulated natural gas mixtures. The uncertainty in the calculated values is approximately one-tenth of one percent for natural gas pipeline conditions.
Some New Mathematical Approaches for Heterogeneous Porous Medium Flow Studies
Authors: Dupuy Michel P. 
Published: December 2007

American Institute of Mining, Metallurgical and Petroleum Engineers, Inc.
This paper was prepared for the 42nd Annual Fall Meeting of the Society of Petroleum Engineers of AIME, to be held in Houston, Tex., Oct. 1–4, 1967. Permission to copy is restricted to an abstract of not more than 300 words. Illustrations may not be copied. The abstract should contain conspicuous acknowledgment of where and by whom the paper is presented. Publication elsewhere after publication in the JOURNAL OF PETROLEUM TECHNOLOGY or the SOCIETY OF PETROLEUM ENGINEERS JOURNAL is usually granted upon request to the Editor of the appropriate journal provided agreement to give proper credit is made.
Discussion of this paper is invited. Three copies of any discussion should be sent to the Society of Petroleum Engineers office. Such discussion may be presented at the above meeting and, with the paper, may be considered for publication in one of the two SPE magazines.

Abstract
Heterogeneity of permeability in natural porous media may, in a number of cases, be described by a stationary statistical model, defined by a Permeability Autocorrelation Function (P.A.F.).
Heterogeneity effects in monophasic flow are two fold:
– a smoothing, or 'variance reductions', effect – a 'permeability averaging', or'permeability composition' effect.
If the flow field dimensions are considerably greater than the scaling parameter of the P.A.F., the porous medium appears as 'macroscopically homogeneous', and the latter effect only is to be noted.
Using a perturbation method referred to the homogeneous medium, Schwydler has analytically treated two standard flow problems and worked out illustrative examples, assuming a typical P.A.F.
Matheron has generalized the formulation and treated the permeability composition problem in two and three spatial dimensions. Conditions of validity of the geometrical averaging rule have thus been defined.
This descriptive heterogeneity model should prove valuable …
as a guide to organize flow studies by numerical simulation on computers; as a reference model in reservoir geology, for collecting and interpreting data on actual gas or oil fields.

Introduction
Permeability heterogeneity is a dominating factor for any flow phenomenon taking place in porous media.
There are, for reservoir engineering, various scales of interest (1), starting from the scale of actual oil reservoirs, and, considering, at an intermediate scale, the geological units (2) which are the basis elements of actual reservoirs.
The problem of taking account of heterogeneity for numerical prevision of flow is very difficult. A reasonable method towards solution can be stated as follows
to concentrate on the study at some given scale; at this scale, to formulate numerically the heterogeneity of the porous medium in terms of some given statistical model; to solve, on this model, the principal flow problems of interest.
A Generalized Finite Volume Discretization Method for Reservoir Simulation
Authors: Rozon Brad J. 
Published: December 2007

ABSTRACTA control volume approach to the discretization of the single-phase reservoir flow equation is presented. The finite volume formulation offers an advantage to classical Galerkin or variational finite element methods in that it permits a direct, physical interpretation of the resulting discrete equations through the enforcement of conservation principles over finite volumes or sub-domains. The scheme presented includes the conventional 5-point discrete equation obtained by conventional finite difference methods as a special case, while maintaining the generality and modelling flexibility associated with finite element methods. The finite volume discretization method provides a perspective from which finite element and conservative finite difference concepts can be implemented in a unified approach. The discrete finite volume equations for single phase reservoir flow are derived in detail and compared to those obtained using a Galerkin finite element approach. A single phase numerical example is included to illustrate the geometric flexibility of the finite volume method.
Simulation of Viscous Fingering by the Pseudospectral Matrix Element Method
Authors: Ku Hwar-Ching , Hirsh R. S. , Taylor T. D. 
Published: December 2007

Abstract
A pseudospectral matrix element (PSME) method which extended the formulation of the pseudospectral matrix (PSM) method to a multi-element scheme, has been applied by the authors to the studies of miscible displacement of fluids in porous media. The resulting pressure Poisson equation which satisfies the differential mass conservation (incompressible flow) is a non-separable self-adjoint operator with Neumann boundary contions in each direction. A separable preconditioner which is constructed from the original operator, in conjuction with the conjugate residual method, provides an efficient iteration scheme to the solution of pressure field. At the high mobility ratio (M = 100), an adaptive method following the idea of minimizing a functional is adopted to resolve the steep fingered front. In the diagonal five-spot model problem, a domain decomposition with the Schwarz Alternating Procedure (SAP) is used to iteratively solve two quarter concentric circles with overlapping area.
The phenomea of fingers’ growing and shielding can be observed in a horizontal slab when a small disturbance in the permeability is subject to the unfavorable mobility ratio (M = 10, 100) between oil and solvent, while in a five-spot reservoir simulation visous fingering still exists even without any permeability perturbation under the mobility ratio M = 10.
The Effects of CO2 Flooding on Reservoir Mineral Properties
Authors: Wolcott J. M. , Monger T. G. , Sassen R. , Chinn E. W. 
Published: December 2007

ABSTRACT
Interactions between CO2 induced organic deposits and mineral matrices were examined. The influence of mineralogy on extent as well as site of deposition, and the effects of organic deposition on mineral properties were determined. In addition, CO2-induced precipitate composition was related to parent-oil composition and geochemical history.
Cores exposed to oil/CO2 flooding were contrasted with cores flooded with oil or CO2 alone. The effects of two different oils were compared as well as the influence of two different minerals, Berea and a carbonate. All cores contained residual brine. Changes due to the stabilization of clays were also explored. Core samples were examined using X-ray diffraction (XRD), scanning electron microscopy (SEM), pyrolysis, and thin-section microscopy.
The nature of organic deposition depended on complex interactions between oil, mineral, and CO2. Organic residue compositions were influenced by parent oil compositions as well as exposure to CO2 flooding. Site of deposition was controlled by mineralogy.
A Correlation of the Physical and Chemical Properties of Three South Louisiana Crudes With Their Degree of Biodegradation
Authors: Wolcott J. M. , Sassen R. , Constant W. D. 
Published: December 2007

Abstract
The effects of naturally-occurring biodegradation on the physical and chemical properties of three crude oils from reservoirs flanking a salt dome in south Louisiana were investigated. Gas chromotographic signatures and saturate/aromatic ratios were used to rank these crudes as to degree of biodegradation. Biodegradation effects decreased with reservoir depth. API gravity, viscosity, average molecular weight, C15+ content, saturate/NSO-compound ratio, saturate/aromatic ratio, elemental C/H ratio, acid number and base number increased with increasing biodegradation. Biodegradation was also found to affect the surfactant properties and molecular weight of crude oil carboxylic acids.
The acidic fractions of two biodegraded crudes were isolated and subjected to a variety of analytical techniques. Phenols and carboxylic acids were major constituents of acidic fractions. The phenolic fractions were brittle solids or tars with high aromatic contents, low elemental C/H ratios and significant quantities of nitrogen and sulfur. The carboxylic acid fractions were viscous liquids with low aromatic content, low nitrogen and sulfur content and relatively high C/H ratios.