bluuebunny/crossref_metadata_2025_split huggingface dataset:
In-Depth Fluid Diversion by Pre-Gelled Particles. Laboratory Study and Pilot Testing.
Authors: Coste J. -P. , Liu Y. , Bai B. , LI Y. , Shen P. , Wang Z. , Zhu G. 
Published: December 2007

Abstract
This paper introduces a new diverting agent that has been developed to control water production in high salinity, high temperature reservoirs. Several dry gels have been crushed and sieved to obtain different cuts of gel particles. The dry powdered gel particles swell in water to give a stable suspension. The swollen pre-gelled (PG) particles do not dissolve in water and can move inside the porous media. Results presented here include test pilots and laboratory experiments. PG particles have been successfully used in two recent pilot tests in Shengli Oilfield, China. Micromechanisms of particle motion and oil mobilization have been studied through transparent glass micromodels experiments. Core tests have also been conducted to verify the selective placement of the particles. According to the experimental laboratory results we can conclude that the mechanisms responsible for the enhancement of oil production are the following:
After swelling and under a high pressure gradient (near the wellbore), the pre-gel particles can deform to pass through small pore throats, ensuring displacement of the residual oil. When the pressure gradient is too small (away from the wellbore) the particles plug the pore throats changing the flow pattern inside the reservoir.
In addition, as the gelation is accomplished before the injection, the PG particle technique overcomes some of the most important problems which can be encountered by classic gel treatments: lack of control of the gelation time, lack of control of the stability of the gel formed or ungelation due to adsorption, dilution or degradation of the polymer or pH change. Furthermore, due to these specific characteristics, this process can be used in oilfield environment that would prevent the in-situ gelation of a classical gelant solution.
Soft Computing for Intelligent Reservoir Characterization
Authors: Tamhane D. , Wong P. M. , Aminzadeh F. , Nikravesh M. 
Published: December 2007

Abstract
This paper presents an overview of soft computing techniques for reservoir characterization. The key techniques include neurocomputing, fuzzy logic and evolutionary computing. A number of documented studies show that these intelligent techniques are good candidates for seismic data processing and characterization, well logging, reservoir mapping and engineering. Future research should focus on the integration of data and disciplinary knowledge for improving our understanding of reservoir data and reducing our prediction uncertainty.
Capturing Depositional Uncertainty: Sunrise-Troubadour Giant Gas-Condensate Fields
Authors: Seggie R. J. , Ainsworth R. B. , Arditto P. , Burns F. , Johnson D. A. , Koninx J. P. M. , Stephenson P. M. , Thompson J. 
Published: December 2007

Abstract
The Sunrise-Troubadour giant gas-condensate fields lie on a massive, broad, low-relief structure 75km long and 50km wide. The fields have a gross reservoir thickness of 80m. They are located on the northwestern boundary of the Australian Plate and form the basis of a proposed green-field LNG project and an Australian domestic gas development.
Statistical volumetric analysis has shown that reservoir quality, distribution and Net-To-Gross ratio (NTG) are the main static uncertainties affecting Gas-Initially-In-Place (GIIP). These parameters are a function of the environment of deposition of the reservoir interval. The low average NTG in some wells (as low as 30%) indicates potential for depositional heterogeneity which can impact dynamic fluid flow through the reservoir. Depositional modelling has therefore been a major focus for field evaluation and appraisal.
The reservoir interval was deposited in a marginal marine setting on a slowly subsiding, broad, low-relief shelf. The overall retrogradational character of the reservoir interval is illustrated by the upward increase in the open marine character of the interbedded shales. There are two major relative sea level falls interpreted which resulted in the deposition of incised-valley and sharp-based, forced regressive shoreface deposits. These sandbodies form the major reservoir units in the fields. Highstand and transgressive deposits are characterised by relatively thin and discontinuous sandbodies.
In order to fully capture the depositional uncertainty inherent in a field of this scale which only has limited well control (six wells), three groups consisting of sedimentologists, stratigraphers and biostratigraphers have independently interpreted the core and wireline data. The result was three different depositional interpretations.
From these interpretations a most likely depositional model was developed. Low and high case 3-D depositional models were generated by varying NTG and sandbody correlatibility and geometries. The adjustment of these parameters reflected the range of depositional interpretations from the three individual expert groups.
These models form the basis of multi-scenario reservoir simulation studies which indicate that development options for these fields are technically robust for the range of perceived subsurface scenarios.
Understanding and Modeling Water Free Production in Transition Zones: A Case Study
Authors: Parker A. R. , Rudd J. M. 
Published: December 2007

Abstract
When production testing an oil reservoir in the oil-water transition zone it is usual to expect water production. This paper shows field examples where dry oil production is encountered in the middle of oil-water transition zones in a non-fractured, mono-modal and essentially homogeneous carbonate reservoir. Whilst it is simple to replicate this behavior in numerical simulators, the reason behind this phenomenon is not so obvious. This paper pulls together current understanding with regard to wettability, capillary pressure, percolation and adsorption through films in order to explain the mechanism behind the phenomenon. Through a greater understanding of the cause of the anomaly it is anticipated that knowledge of pore scale processes will lead to improved recovery methodologies.
The Field, which is the subject of the case study, is in the appraisal stage (6 well penetrations, no production) and is composed of a series of stacked Carbonate reservoirs located in shallow water offshore of the UAE. The entire oil column has been cored, extensive Mercury Injection data was available for analysis and the oil-water transition zone extends across 70% of the oil column.
Integrating Resistivity Data with Production Data for Improved Reservoir Modelling
Authors: Wang Pengju , Horne Roland N. 
Published: December 2007

Abstract
This work deals with the problem of estimating reservoir permeability and porosity distribution from multiple sources, including production data and well logging data. The work focuses on integrating long-term resistivity data into the parameter estimation problem, investigating its resolution power both in the depth direction and in area.
The resistivity logging tool considered in this project is a new tool proposed for permanent installation. The tool is installed in the cement around the well when the well is completed, and is capable of recording the long-term resistivity variation around the wellbore.
In this work, the Poisson equation with mixed boundary condition was used to model the infinite potential field around the resistivity logging tool. The behavior of the reservoir was modeled with a standard three-dimensional, two-phase, black-oil model. The resistivity response simulator was integrated into the flow simulator through Archie's law.
The Gauss-Newton algorithm was used to solve the inverse problem. This algorithm requires the calculation of the derivatives of the observation data with respect to the unknown parameters. These derivatives are called the sensitivity coefficients.
By running several simple inverse problems, it was concluded that the resistivity data has high resolution power in the depth direction and is capable of sensing the areal heterogeneity.
Development of Operations Reference Plan (ORP) for Asset Management
Authors: Sulaiman Salahuddin , Husin Muhammad Taufik 
Published: December 2007

Abstract
The business processes for oil and gas production comprise exploration, appraisal, development, production, sales and abandonment. Typically a field has an economic producing life of 15 to 25 years compared to 3 to 7 years to explore, appraise and develop. Production is an important phase in which hydrocarbons are produced and assets are maintained until the economic limit is reached. Oil production from mature fields will continue to deplete while water production increases. Produced water is to be disposed off in an environmental friendly manner meeting regulatory requirements. Artificial lift to supplement the reservoir energy is increasingly needed to sustain production. Facilities are aging and maintenance activities are expected to increase and hence cost in materials, logistics and human resources. The emphasis is to manage the producing assets in the most profitable manner, i.e. maximize the return on investment through improvement in performance and cost reduction over the complete life cycle. Very often it requires application of new technologies to contain the operating costs and increase oil and gas production. An effective, integrated planning system is required to improve the management and control of operational activities in each asset, and to optimize development over the full life cycle of the asset. To this end, the Operations Reference Planning (ORP) concept was developed as an integrated multi-disciplinary business model. It provides a framework system that will allow various future development scenarios to be tested, and to establish a clear understanding of the parameters that will affect return on investment with proper regard for safety and the environment. An ORP has been developed for the Baram field, one of the nine producing fields in the Baram Delta area, offshore Sarawak, Malaysia, operated by PETRONAS Carigali Sdn Bhd (Sarawak Operations). The Baram field, which contains billion barrels of oil initially in place, is one of the largest producing fields in the area. The field came on stream in 1971 and is still producing merrily after almost three decades of production. Furthermore, there is substantial scope for additional development that will prolong the field life well into the new millennium. This paper discusses PETRONAS Carigali Sdn Bhd's (Sarawak Operations) experience in developing the Operations Reference Plan for the Baram field. It highlights the methodology undertaken, organizational and resources requirements, roles and responsibilities of key positions, multi-disciplinary team approach from subsurface to surface, sharing of good practices, production enhancement and cost reduction initiatives to prolong the field economic life.
Dynamic Model of Wormhole Formation Demonstrates Conditions for Effective Skin Reduction During Carbonate Matrix Acidizing
Authors: Fredd C. N. 
Published: December 2007

Abstract
The success of carbonate stimulation treatments is highly dependent upon the formation of conductive flow channels, or wormholes. Success requires wormhole formation during matrix acidizing treatments and lack thereof during fracture acidizing treatments. The structure of the wormhole channels, which varies significantly with flow conditions and acid/mineral properties, ultimately controls the effectiveness of a stimulation treatment. This paper describes a dynamic model of wormhole formation that accounts for wormhole structure based on the Damköhler number. It addresses the issue of scaling laboratory data to the field by including the effects of fluid loss and wormhole competition. The model predicts skin evolution based on basic input parameters and is used to demonstrate matrix acidizing strategies for optimum skin reduction with several acid systems.
The results demonstrate that, under typical treatment conditions, conventional matrix treatments with straight HCl cause face dissolution and provide little reduction of skin. Under the same conditions, alternative fluids such as weak acids and emulsified HCl create dominant wormhole structures that penetrate deep into the formation. While these fluids are more effective than straight HCl (especially at high temperatures and low injection rates), additional injection strategies can be used to increase the depth of penetration and, in turn, improve skin reduction. Injection strategies such as increasing the injection rate or decreasing the rate of dissolution (by changing the fluid properties) promote deeper penetration of wormholes. These injection strategies rely on maintaining an optimum Damköhler number for effective wormhole formation during matrix stimulation treatments. The model also applies to the selection of fluid properties to control wormhole formation during fracture acidizing treatments.
What Does Deming Have To Do With Oil and Gas?
Authors: Matthews V. , Linger D. B. 
Published: December 2007

Abstract
Deming's principles of management are often regarded by individuals in the petroleum industry as being applicable to manufacturing operations, but not to E&P activities. The argument usually asserts that E&P activities are so varied that Deming's method of analyzing "the system" can't be used in the oil & gas business.
The experience of one small, independent company shows quite the opposite, i.e. that Deming's methods are indeed quite useful in many areas of E&P operations and they can lead to greatly improved operations. A specific example regarding the inability of getting wells drilled according to a budgeted schedule serves to illustrate how several of these principles applied to the problem resulted in vastly improved performance.
Through-Life-Cost (TLC) Management: The Key to Reducing OPEX
Authors: Flatt Robert N. , Condic Sam , Marks Vicki 
Published: December 2007

Abstract
Increasing sensitivity to crude price fluctuations will require operators to reduce costs for drilling, completion and production operations. A key component of this strategy is the collaborative management of equipment assets by operators and suppliers to reduce cost over the complete life cycle of the equipment. This paper analyzes benefits derived from TLC Management Programs undertaken with customers worldwide to reduce operating expenses.
Characterization of the Dynamic Fracture Transport Properties in a Naturally Fractured Reservoir
Authors: Baker Richard O. , Contreras Ruben A. , Sztukowski Danuta 
Published: December 2007

Abstract
In characterizing and modeling the performance of naturally fractured reservoirs (NFR), fracture length and fracture connectivity (permeability) are often assumed to be constant. A number of field tests done on Spraberry Trend wells suggest this assumption is not always true for NFR.
Pressure transient tests and decline analyses have been used to determine permeability, skin, fracture connectivity and average reservoir pressure for the Spraberry Trend reservoir of West Texas. It has been hypothesized by L. Elkins1 that fractures open and close due to pressure effects. In order to better understand these effects and fluid movement pathways, a number of specialized pressure transient tests have been conducted and analyzed in the E.T. O'Daniel Unit of Spraberry. This included constant pressure decline rate tests, build up tests, step-rate tests, falloff tests and a multi-well interference test, carried out so as to minimize the risk of induced fractures which can cause reduced sweep efficiency and fluid losses to other non pay zones. Results indicate that fracture systems are very stress sensitive in the Spraberry formation, with fractures opening and the effective permeability increasing at high injection rates (in addition, reservoir flow simulation has also confirmed that permeability is stress sensitive).
Interwell Seismic Data for Reservoir Characterization
Authors: Justice J. H. , Woerpel J. C. , Watts G. P. , Waddell W. 
Published: December 2007

Abstract
As part of a DOE Class II Oil project, a wide variety of data were acquired in a Permian Basin oil field. This included core, log and petrophysical data, as well as interwell borehole seismic data. Borehole seismic data was acquired to provide baseline surveys for future CO2 monitoring, but also to investigate its use for high resolution reservoir characterization. A method was developed to derive detailed porosity and permeability maps between wells using the log, core, and interwell seismic data together with certain petrophysical relationships. The resulting interwell porosity and permeability maps provide a natural basis for extracting statistics, such as variograms, needed for geostatistical reservoir modeling and simulation. This procedure provides an important new alternative for obtaining spatial statistics needed for geostatistical reservoir studies.
Advances in Deep-Penetration Density Logging
Authors: Chapin David A. , Ander Mark E. 
Published: December 2007

Abstract
The borehole gravity logging tool, used as a deep investigation density method that can image through casing, is enjoying a renaissance. Originally designed in the early 1970s, the tool suffered from hardware limitations, such as size, deviation, and speed, which now keeps it out of the majority of wells drilled. These artificial limitations can now be overcome with modern engineering and new electronic components technology that was unavailable a few years ago. New advances in gimbals and leveling move borehole gravimetry forward into the 21st century. The fundamental principles of borehole gravity remain a sound and valuable technology for all phases in the life of an oil field. Numerous examples and case studies can be cited which attest to borehole gravity's value in exploration, formation evaluation, reservoir monitoring, and missed pay opportunities.
Enzyme Breaker Technology Increases Production, Grayburg-Jackson Field, Southeast New Mexico: A Case History
Authors: Malone Mark R. , Nelson Scott G. , Jackson Randy 
Published: December 2007

Abstract
The subject matter of this paper will describe organoborate fluid systems in combination with guar specific enzyme breakers, their application, and how they were used to improve production in the Grayburg-Jackson field of SE New Mexico. Furthermore, the paper will discuss the completion objectives in the Grayburg-Jackson field as they relate to stimulation treatments and explain how wells were normalized for the purpose of this study. Finally, production results will be examined to compare organoborate/guar specific enzyme breaker combinations verses monoborate fluid systems with non-specific breakers.
A Pulsed Neutron Analysis Model for Carbon Dioxide Floods: Application to the Reinecke Field, West Texas
Authors: Odom Richard , Hogan Phil , Rogers Carroll , Steckel F. Merle 
Published: December 2007

Abstract
Rienecke field is one of a series of fields in the Horseshoe Atoll of the Midland Basin. This carbonate reservoir has fairly good lateral and vertical continuity and is confined in a dome-like structure. A gravity-stable crestal carbon-dioxide flood was begun in 1997 by injection into five wells at the high point of the structure. Pulsed-neutron logs run through casing provide a method to monitor reservoir dynamics and locate oil production targets.
The first step in developing a cased-reservoir analysis model is to estimate the carbon dioxide content. This is done by correlation of the cased-hole neutron and density porosities from the pulsed-neutron system. In developing a three-phase saturation model (oil, water, carbon dioxide)the effects of the carbon dioxide on the oil and water saturation measurements must be determined. Computer simulations of tool response are utilized in conjunction with field data to develop the model and the uncertainties in the saturations.
An example log and analysis demonstrate the capabilities of the reservoir analysis model. The analysis results are compared to production and historical data for the field.
Efficient Approach for Well Calibration in Reservoir Simulation After a Successful History Match
Authors: Siu Alan L. , Salamah Majid M. , Al-Khatib Mohammed H. 
Published: December 2007

Abstract
A systematic and efficient approach for well calibration against wellhead pressure has been developed and verified for two reservoir simulators. The new approach integrates the producing well conditions into the flow table generation step so that the well productivity can be matched while generating the flow table. The main advantage of this approach is that most of the calibration effort is spent on individual wells, which requires less computational effort. Once the appropriate flow tables are generated, it only takes a few reservoir simulation runs to calibrate all the wells in the model. The computer applications based on this approach yield significant cost savings by reducing the project time from weeks to days, and by improving the quality of the well calibration.
Connectivity and Permeability in Fracture Networks Obeying Power-Law Statistics
Authors: Rossen W. R. , Gu Y. , Lake L. W. 
Published: December 2007

Abstract
Recent research on naturally fractured reservoirs suggests that microfractures and megafractures are all part of a single population that shows a power-law relation between frequency of occurrence and fracture aperture or length. The objective of this work is to investigate the effective permeability of fracture networks whose fractures obey power-law scaling relations.
For the simple case where each fracture extends through the region of interest, we present a formula that relates effective fracture-network permeability to the distribution of fracture apertures. In this simple case, the effective permeability of the region is dominated by the single largest fracture in the region.
In reality, of course, flow through fractures depends on whether fractures interconnect. Connectivity at one length scale does not relate simply with connectivity at another scale, if fracture properties obey power-law scaling relations. Fracture populations based on frequency/length scaling exponents derived from field data are not guaranteed to interconnect on either the microscopic or megascopic scales. Computer-capacity limitations make it difficult to include enough fractures to model a region even the size of one reservoir grid block. Clustering of fractures into swarms appears to be the key to fracture interconnectivity.