bluuebunny/crossref_metadata_2025_split huggingface dataset:
Faulted Reservoirs Characterization by an Image Processing Technique
Authors: Martinez-Angeles Raymundo 
Published: December 2007

ABSTRACT
This paper has developed an image processing method for obtaining the discontinuous areal distribution of oil parameters (formation top, porosity, water saturation,...) of faulted heterogeneous oil reservoirs. For its application it requires the previous knowledge of a set of discret values z(k,l) from well-logs and seismic profiles. Faulted structures were discretized into continuous structures or blocks bounded by faults. The theoretical fundamental assumption of the proposed method establishes that the natural distributions can be considered as the superposition of several elementary brownian distributions, represented by discret values z(k,l), whose physical model is the diffusion differential equation and its solution associated. This is a technique that allows the representation of a composed brownian distribution as a linear combination of all elementary brownian functions. For illustrating the operational aspect of brownian analysis, two examples are studied. The results are presented as a digital images by means of an image processing software.
This method can be applied in mapping, three dimensions interpolation and reserves calculation of faulted reservoirs.
A Simplified Method for Analyzing Naturally Fractured Reservoirs Based in Mathematical Properties of Type Curves
Authors: Alvarado D. A. , Briones M. F. 
Published: December 2007

ABSTRACT
A new simplified method is presented for analyzing wells with wellbore storage and skin in double porosity systems. The method applies to damaged, acidized and fractured wells in fissured reservoirs, and it is based on the mathematical properties of the solutions (Bourdet et al. 's solutions1,2).
By taking the second derivative of the dimensionless pressure solution for a well with wellbore storage and skin in a homogeneous system a locus is defined which contains the maximun of the curve of p/tp/Cp) vs. tD/CD, for each value of the parameter CD exp(2S). The use of the maximun points curve together with the derivative value for radial flow of the total system (fracture and matrix) is used to define a Match Point on the log-log field data graph. This Match Point is also defined on the Type Curve and allows the calculation of C and k, without the neccessity of using the conventional Type Curve Analysis, nor a computer program for pressure transient analysis.
Further properties of the solutions are used to determine S, ω and X, making use of the transition curve minimun (for the pseudo-steady interporosity flow model) and the late transition data (for the interporosity flow model). The simplified analysis presented in the paper is illustrated with actual field examples from several different fissured reservoirs; it is accurate enough for engineering purposes (average relative errors less than 10%) and only requires a few calculations, using the log-log field data graph and a hand held calculator. It can be used as a screening method of analysis. It can also be implemented in more advanced programs of analysis.
Interpretation Model for Fracture Calibration Tests in Naturally Fractured Reservoirs
Authors: Ehlig-Economides C. A. , Fan Y. , Economides M. J. 
Published: December 2007

Abstract
Recent work provided a model for the fracture calibration test in a homogeneous reservoir and an interpretation methodology that enables determination of the formation permeability. The previous study used a rate-dependent skin for the filtercake resistance. Pressure drop in the formation was modeled using a closed form solution for linear flow. The need to analyze tests conducted in naturally fractured reservoirs has motivated the work in this paper.
To model dual-porosity reservoir heterogeneity, the linear flow closed form solution was replaced by an analytical solution. The heterogeneous model uses a standard pressure transient model formulation while incorporating the filtercake resistance from the previous work.
Analysis of data from fracture calibration tests in naturally fractured reservoirs shows that the homogeneous model fails to capture transient behavior attributed to natural fractures. Sensitivity studies using the new model illustrate the pressure falloff response behavior and show what can be determined from the failoff analysis.
Numerical Simulation by the Quadrature and Cubature Methods
Authors: Civan Faruk 
Published: December 2007

ABSTRACT
In this paper, practical quadrature and cubature formulae for numerical differentiation, integration, interpolation, and extrapolation purposes are derived; the method for determination of the quadrature and cubature weights is given, and the procedure for development of finite-analytic quadrature and cubature schemes is presented. It is demonstrated that these methods provide rapid and practical means of obtaining algebraic discretization formulae for numerical approximation.
Application of Multiple Techniques to Determine In-Situ Directions in Marlin and Albacora Fields
Authors: deLima B. B. , Viana R. 
Published: December 2007

Abstract
This paper presents techniques used to determine in-situ stress orientation and magnitude in the Marlin and Albacora offshore fields located in the Campos Basin. These data were collected from anelastic strain recovery (ASR) tests, a low-frequency dipole tool, and a downhole extensometer that provides a new means of analyzing in-situ stress directions and rock properties.
The paper also describes general prejob planning for drilling ship operators performing a microfracturing stress test in deep-water wells. Discussion includes equipment configuration and layout, string configuration, and fluid used to create and propagate the required hydraulic fractures. The possible causes of success or failure for each running session are also discussed.
Improved Recovery Strategies for Heterogeneous Reservoir With High Permeability Contrast
Authors: Surguchev L. M. , Hanssen J. E. , Johannessen H. M. , Abusdal Turid 
Published: December 2007

Abstract
The present paper is a case study of improved oil recovery (IOR) process evaluation for a reservoir in the North Sea that has been particularly diffi-cult to develop by waterflooding — the method of first choice in the area — due to its complex geology and faulting and to the coexistence of regions of very high and very low permeability.
First, a multicriterion analysis based on general IOR experience and the applicability of specific processes in different geophysical conditions was used for a first-order screening of promising IOR technologies. Next, possible development scenarios for a particular stratified formation with high permeability contrast were modelled analytically, using an IOR screening tool developed in-house, and numerically, using a commercial reservoir simulator. Conventional water and gas injection, various horizontal well injection and production scenarios, as well as "traditional" enhanced oil recovery (EOR) methods, such as surfactant and polymer flooding and Water-Alternating-Gas (WAG) injection, all showed limited efficiency for the reservoir in question.
However, the study also showed that novel, in-novative water/gas injection processes and foam-assisted WAG injection, in combination with ho-rizontal production wells, may give considerable improvement of reservoir sweep efficiency. Field model simulations demonstrated high recovery potential of these new processes. The practical applicability in offshore and deep-water completions for these processes were considered with the conclusion that field-scale implementation may be quite feasible.
Numerical Simulation of Fracture Rocks and Wave Propagation by Means of Fractal Theory
Authors: del Valle G. Raul 
Published: December 2007

Abstract
A numerical approach was developed for the dynamic simulation of fracture rocks and wave propagation. Based on some ideas of "percolation theory and fractal growth", a network of particles and springs represent the rock model. To simulate an inhomogeneous medium, the particles and springs have random distributed elastic parameters and are implemented in the dynamic Navier equation. Some of the springs snap with criteria based on the confined stress applied, therefore creating a fractured rock consistent with the physical environment.
The basic purpose of this research was to provide a method to construct a fractured rock with confined stress conditions as well as the wave propagation imposed in the model. Such models provide a better understanding of the behavior of wave propagation in fractured media. The synthetic seismic data obtained henceforth, can be used as a tool to develop methods for characterizing fractured rocks by means of geophysical inference.
The Fault Block Model: A Novel Approach for Faulted Gas Reservoirs
Authors: Ursin J- R. , Mørkeseth P. O. 
Published: December 2007

Abstract
The Fault Block Model was designed for the devel-opment of gas production from Sleipner Vest. The reservoir consists of marginal marine sandstone of Hugine Formation. The structure is dome shaped and highly faulted with good reservoir productivity. Based on geological interpretation, location and extent of faulting in the reservoir was carried out and the effect of faulting as flow barrier was evaluated. Internal cross-flow communications between adjacent fault blocks defined by throw of faults were established.
The model redefines individual fault block traps in terms of block volume and cross-flow probability to adjacent blocks and estimates the number and lo-cation of wells required for optimum recovery of the gas reserves. The model predicts the corresponding well coverage, from which production profiles are calculated.
Modelling of highly faulted and compartmentalized reservoirs is severely impeded by the nature and extent of known and undetected faults and, in particular, their effectiveness as flow barrier. The model presented is efficient and superior to other models, for highly faulted reservoir, i.e. grid based simulators, because it minimizes the effect of major undetected faults and geological uncertainties. The geological interpretation and its uncertainty is minimized using fault block volume and cross-flow probability, which subsequently may translate into gas production profiles. The geological uncertainties are carried through in the model by error propagation techniques.
In this article we present the Fault Block Model as a new tool to better understand the implications of geological uncertainty in faulted gas reservoirs with good productivity, with respect to uncertainty in well coverage and optimum gas recovery.
Meeting the Challenges of Deepwater Gulf of Mexico Drilling With Non-Petroleum Ester-Based Drilling Fluids
Authors: Carlson Tom , Hemphill Terry 
Published: December 2007

Abstract
The search for recoverable hydrocarbons in the Gulf of Mexico has moved into increasingly deeper waters. Since its introduction in the Gulf of Mexico in 1993, the ester-based drilling fluid system has been used on five deepwater wells. This paper describes the applications of the ester-based system and its ability to handle the special challenges of deepwater drilling in the Gulf of Mexico.
The Generation of Grid Block Permeabilities from Core Data
Authors: Yang Y. S. , Thompson C. J. , McCarthy J. F. 
Published: December 2007

Abstract
The grid blocks used in reservoir simulations typically have dimensions in the order of tens or hundreds of metres, whereas the core data which are used to generate the grid block permeabilities have a scale of only a few centimetres. Thus it is necessary to scale up the data over several orders of magnitude to derive the "effective" permeability distribution at the grid block scale. This is commonly done by taking standard measures of the mean of the data (e.g. arithmetic, geometric or harmonic mean) and making ad hoc assumptions about the rescaled variance. Such an approach can lead to costly errors. However, the obvious alternative — to iteratively scale up from the core to the grid block scale via detailed flow simulations — is often not feasible due to computational limitations. This problem has been resolved in recent years by the development of fast and accurate algorithms for computing the effective permeability of large systems, containing up to millions of grid blocks.
This paper describes a computationally efficient software package which has been developed to generate grid block permeabilities for reservoir simulations from core data. Upscaling is performed using algorithms based on random walks and real-space renormalization group methods. Geological correlations and anisotropy at the core scale can be incorporated using geostatistical techniques (e.g., sequential gaussian simulation). The paper emphasises a practical application of the software to field data.
Thermometric Well Testing on the Vietnam Offshore
Authors: San T. N. , Shtyrlin V. F. , Vakhitov G. G. , Loi L. M. , Listengarten Leonid , Hien D. L. 
Published: December 2007

ABSTRACT
It is impossible to control and adjust an oil and gas field development without determining the flow intervals of production wells. For that it is preferable to get production profiles by using the downhole flowmeter. There are, however, some main restrictions for wide-spread application of them on the offshore of Vietnam as follows: –The flowmeter spinner velocity cannot indicate correctly in the open hole wells having a ununiform diameter.–It is unable to carry out in the case when the tubing shoe is lower than top formation on 300 - 500m.
In this paper, the authors present a summary of temperature profile method to determine the flowing and intaking intervals of wells drilled in basement of the White Tiger Field on Vietnam offshore.
For last 2 years more than 30 wells were surveyed by this method in the above mentioned conditions.
This paper presents the theory and practic of well temperature profile surveys, the concrete examples of data interpretation using the software "Oiltest".
Project Rulison and the Economic Potential of Nuclear Gas Stimulation
Authors: Coffer H.F. , Frank G.W. , Bray B.G. 
Published: December 2007

Discussion of this paper is invited. Three copies of any discussion should be sent to the Society of Petroleum Engineers office. Such discussions may be presented at the above meeting and, with the paper, may be considered for publication in one of the two SPE magazines.

Abstract
Project Rulison was designed to use underground nuclear technology to determine the potential of this technique for commercial development of the Mesa-verde formation of the Rulison Field in Garfield County, Colorado. A method of stimulation, far greater in magnitude and efficiency than conventional hydraulic fracturing, is needed to recover the gas at economic rates.
Detailed testing of the Project Rulison exploratory well, R-EX, provided data on geology, hydrology and provided data on geology, hydrology and reservoir characteristics. The data obtained from the testing have been used to determine the flow capacity of the Mesaverde reservoir. The reservoir characteristics were then used as input data to make predictions of post-shot reservoir performance in the nuclear stimulated well, using a radial, unsteady state gas flow computer model. The calculations show that rates of production will be sufficient if costs production will be sufficient if costs can be controlled. Costs of nuclear stimulation must be drastically reduced for a commercial process. The total Project Rulison cost will be approximately $5.9 million. At such prices, nothing can possibly be prices, nothing can possibly be commercial; however, as outlined in the paper, these costs can come down in a paper, these costs can come down in a logical step-wise fashion to an economic number.
A nuclear explosive with a design yield of 40 kilotons was emplaced and detonated in a 10-3/4" casing at a depth of 8426' below ground surface and detonated on September 10, 1969. A preliminary appraisal of the data taken at shot time indicate that the explosive behaved as predicted. The explosion was completely contained underground as predicted and no major seismic damage occurred. The post-shot reentry program, in the spring of 1970, will include reservoir testing to determine the degree of stimulation achieved.

Introduction
The greatest challenge to the oil industry has always been how to make available oil and gas at an economic rate. The increasing costs of exploration and the impending shortage of natural gas have made the economic development of marginal resources not only attractive, but necessary.
Prediction of Critical Condition for Fines Migration in Petroleum Reservoirs
Authors: Rahman S. S. , Arshad Aziz , Chen Hong 
Published: December 2007

ABSTRACT
Formation damage due to fines migration is a threshold type process in that there exists a critical condition at which a petroleum reservoir is susceptible to formation damage. This paper presents a physical model for predicting the critical condition for particle deposition based on experimental data and trajectory analysis. Suspensions (bentonite, kaolinite) were passed through a capillary (100 fim) at a controlled flow rate and at the same time, pressure drop across the capillary was monitored. Based on the log jam effect a criterion is proposed to predict the critical condition for particle deposition in porous media.
Management of Critical Equipment (Wellhead Systems)
Authors: Barry A. G. 
Published: December 2007

ABSTRACT
Precise documentation is a key dement in the management and control of critical equipment, Having correct and easily accessible information for equipment which in some cases is in excess of 20 years old has saved Esso Australia Ltd thousands of dollars in engineering time and has reduced rig downtime.
Safety and the Environment are of prime importance in Esso operations and the management of critical equipment is instrumental in achieving objectives for these areas.
Esso has completed an extensive program to document and control critical wellhead equipment and this has involved: Surveying and documenting the 300 existing wellheads offshore;Increased emphasis on material specification and control;Reviewing and implementing new techriology;Increased control over wellhead equipment refurbishment; andIncreased emphasis on offshore wellhead maintenance.
Benefits experienced by Esso after increasing the focus on critical equipment management include increased safety, increased confidence in equipment, decreased engineering time, and decreased rig downtime related to incorrect or incomplete information.
Enhanced Statistical Variation Method For Determining Zone Isolation In Complex Cements
Authors: Graham W. L. , Harness P. E. , Griffith J. E. , Lee S. , Miller J. , Maloney B. J. 
Published: December 2007

ABSTRACT
Complex, or non-standard, cement slurries create special, difficult cement evaluation problems which are magnified when high density drilling fluids are used. These complex slurries include lightweight cements (water-extended, ceramic bead, and nitrified cements), gas-channeled cements, multistage density cements, as well as intervals of cement that are contaminated with drilling fluid. Current cement evaluation methods, via conventional logging techniques, are based on signal amplitude, acoustic impedance, and compressive strength relationships. These properties are derived from the materials behind the pipe and interpretation methods rely on how these properties differ in fluids versus standard cement. This desired contrast is not always evident in complex cements; however, statistical variance techniques have been developed that permit accurate interpretations of zone isolation in low-density cements.
This new approach to determining zone isolation in lightweight and complex cements with ultrasonic cement evaluation tools is called Statistical Variation Plot (SVP) and is based on the following two factors: Distinguishing solid materials from fluids in the casing-borehole annulusAssuming that solid material cannot be displaced during the remedial cementing operation whereas fluids may be displaced1
It will be shown that this technique is superior to conventional evaluation techniques when the acoustic properties of the cement are similar to the acoustic properties of the annular fluid.
New Cement Additive Improves Slurry Properties and Saves Cost
Authors: Pollard Robert , Hibbeler Jeff , Dilullo Gino , Shotton E. A. 
Published: December 2007

ABSTRACT
A new cement additive has been developed which improves slurry performance and reduces cost. The additive is a vitrified aggregate of calcium-magnesium aluminosilicates with potential cementitious reactivity, hereafter abbreviated CMAS. CMAS has been used successfully on oil and gas wells throughout Indonesia.
The purpose of this paper is to illustrate the technical enhancements and cost effectiveness of slurries incorporating CMAS. Laboratory data is presented and working mechanisms are defined to highlight CMAS's positive effect on; compressive strength, fluid loss control, free water control, gas migration control, resistance to strength retrogression and aggressive fluids. Finally, case studies and an economic analysis are presented to show the cost savings for actual well applications.
Drilling a High-Angle Exploration Sidetrack Downdip Along Bedding, Gobe Main Prospect, Papua New Guinea
Authors: Jordan J. A. , Valenti G. L. 
Published: December 2007

ABSTRACT
The Gobe 4X sidetrack exploration well was drilled in a remote area of the Southern Highlands Province of Papua New Guinea using an innovative sidetrack technique for delineating hydrocarbons. After gas was encountered in the Gobe 4X straight hole, a non-conventional sidetrack was drilled down dip along the bedding plane of the reservoir sand and determined the gas-oil contact and the oil-water contact with a single wellbore thereby establishing the limits of the oil band. This was accomplished despite a difficult well trajectory, high deviation angle, large stepout and limited structural information.
The Application of In-Situ Stress Measurement and Numerical Stress Analysis to Coalbed Methane Exploration in Australia
Authors: Enever J. R. , Bocking M. A. , Clark I. H. 
Published: December 2007

Abstract
Exploration for coalbed methane in Australia has evolved over the past few years to a point where the focus is very largely on the targeting of regions of relatively higher permeability. Gas content has generally been found to be adequate enough to encourage commercial development. Permeability has, however, often been found to be too low by comparison with overseas experience to suggest commercially viable gas production rates.
The unravelling of an understanding of coal permeability and its relationship to the geological environment is being helped by the application of in- situ stress measurement (conducted in coal and associated sediments) and numerical stress aiialysis. Knowledge of the in-situ stress field becomes a means by which to quantify the relationship between coal permeability and the related structural geological framework, leading ultimately to a better basis to guide the development of exploration strategies.
This paper describes the results of in-situ stress measurements conducted in a number of coalbed methane exploration holes in the Sydney Basin and associated stress analyses conducted to examine the influence of in-situ stress and geological structure on coal seam permeability as measured by well test.