bluuebunny/crossref_metadata_2025_split huggingface dataset:
Optically Derived Numerical Descriptors for Classification of Carbonate Rock Fabrics
Authors: Conley C.D. , Davis J.C. 
Published: December 2007

Abstract
Carbonate rocks, although relatively simple in their basic mineralogy, present a bewildering array of constituents, textures, structures, and diagenetic features, as well as complex pore geometry. For these reasons, detailed quantitative studies of carbonate rocks require a large investment of time on the part of the carbonate petrologist simply for the purpose of data gathering. Conversely, purpose of data gathering. Conversely, if large numbers of samples are to be studied or if time and cost are important factors, relatively little information is extracted from the available samples.
Derivation of petrographic data from carbonate rocks may be considered a problem of image analysis. One approach to such problems is to utilize techniques and algorithms developed in the field of pattern recognition. Identification of rock components and characterization of rock fabric basically involve signature analysis and pattern interpretation. In addition to the characterization of rock constituents, it is equally important to define the nature and distribution of rock pore systems, which may be at least as complex as grain fabrics.
It is possible to identify individual constituents of carbonate rocks, such as biotic constituents, by a multispectral process. with this procedure, the reaction process. with this procedure, the reaction of different phases to staining agents, differences in surface texture, crystal fabric, and other "differences in appearance" are combined to achieve unique spectral signatures for each class of constituents. Presently available equipment, originally Presently available equipment, originally designed for analysis of multispectral radar and light imagery from satellites, can classify ten different constituents identified by up to five different spectral characteristics. Once rock constituents have been properly identified, individual particles can be counted, their areas particles can be counted, their areas computed, and statistical measures derived from the image. Equipment can be computer-interfaced for immediate data reduction and display.
Optimum Acid Volume Estimation Using Real-Time Skin Evaluation
Authors: Boonyapaluk P. , Hareland G. 
Published: December 2007

Abstract
During matrix acidizing stimulation jobs, the use of more acid does not mean more skin reduction during the treatment. The excessive acid volume serves only to dissolve and weaken the matrix rather than remove the damage. The optimum amount of acid needs to be determined in each matrix stimulation case. This is done by calculating the real time skin value which is used to estimate the optimum volume needed.
The acid volume and type used in matrix acidizing stimulation is usually based on the experience of the operator in the field. Trial-and-error or on-site injectivity measurements are used to optimize the acid volume. In order to limit trial-and-error exercises, a real-time on-site treatment evaluation method has been developed to assist the field engineer with a new real-time matrix volume estimation technique. History matching and curve fitting the early stages of the acidizing job, the method determines when the maximum damage removal is obtained and corresponding acid volume.
This work proposes the use of real-time matrix acidizing data in conjunction with real-time skin effect calculations to estimate the optimum acid volume to be used on-site. The results are compared with three acidizing field cases in the paper, but has been verified for sixteen (16) field cases. The method can be used for optimizing acid volume during matrix stimulation in progress and deciding when to stop pumping the acid.

Introduction
The concept of skin effect has been used as a magnitude of near wellbore flow impairment. The total skin effect is a multi-component quantity including mechanical skin effects such as mud solid and filtrate invasion during drilling and cementing, formation debris during perforation, and fine migration during production. Actually, the skin effect accounts for any deviation from an ideal undamaged, open-hole, vertical well. "Damage" may be caused by a number of phenomena on which traditional acidizing has no effect. Some of these pseudo-damage phenomena are gravel-pack and partial perforation and penetration.
Matrix acidizing stimulation is a treatment intended to remove near-wellbore damage. The determination whether to and how much to stimulate a well and the type of acid treatment should depend on comprehensive pre, real-time, and/or post analysis with high emphasis on quality data gathering. Matrix acidizing job effectiveness can be assessed through real-time or post treatment evaluation of data collected during the acid treatment.
During the matrix acidizing treatment, fluids are injected into the well, causing a pressure response recorded at the wellhead.
P. 381
Lease Operatorships and Farmouts: Changing the Oil Production Scenario in Trinidad's Land-Based Fields
Authors: Hosein Aleem 
Published: December 2007

Abstract
The history of the oil industry in Trinidad's land-based fields, reflects a domination by foreign multinationals initially, followed with ownership by various state-owned oil companies. Recently however, local entrepreneurs have been afforded the opportunity to participate to some extent, in oil production activities of the land-based operations of the state-owned oil company.
The state-owned oil company of Trinidad and Tobago has over five thousand (5000) inactive wells. Because of limited capital resources and the resultant low priority for reactivation, a programme of leasing blocks of these idle wells to small independent operators was initiated in July 1989. This programme is currently being expanded because of its initial success. In addition, acreages are being offered for farmout operations, again because of the scarcity of capital funds for internal investment and the associated risks involved.
As a consequence of these programmes, the oil production scenario in Trinidad's land-based operations is undergoing a radical transformation. This paper reviews the current status of lease operatorships and farmouts and discusses the key issues involved.

Introduction
Trinidad is the most southerly of the Caribbean Islands and is located to the east of Venezuela (Figure 1). The major part of the history of the oil industry of Trinidad's land-based operations reflects a domination by foreign multinationals including Shell, Texaco and British Petroleum amongst other smaller foreign companies. Over the years, the land-based assets of these companies were acquired by the Government of Trinidad and Tobago to form two state-owned oil companies TRINTOC and TRINTOPEC. In 1993, these two companies were eventually merged into one state-owned oil company, PETROTRIN.
In the late 1980's, because of the low oil prices, many wells became uneconomic to produce and were left idle.
Impact of Foamy Oil Mechanism on the Hamaca Oil Reserves, Orinoco Belt-Venezuela
Authors: de Mirabal M. , Gordillo R. , Rojas G. , Rodriguez H. , Huerta M. 
Published: December 2007

Abstract
This paper summarizes an integrated field, experiments and computer simulation research program conducted to support a review of the reserves and development plan for the Hamaca Area in the Orinoco Belt (OB), Venezuela. The impact of the foamy oil mechanism on the Hamaca heavy-extra heavy Oil reserves and the importance of understanding this behavior is presented in this paper. The study was conducted in reservoirs with the largest production history (within the OB). The experimental results showed in-situ formation of non-aqueous oil foam with high gas retention, improving oil mobility and leading, therefore, to high well productivity. An experimental recovery factor over 10% was obtained under primary conditions so it was possible to increase oil reserves by approximately 30% over the currently accepted volumes. Experimental results provided input parameters to perform preliminary simulation runs which would allow the modification of well spacing schemes, the generation of a high-probability production profile, and the optimization of artificial lift systems, incorporating larger capacity equipment.

Introduction
When the exploitation of Hamaca heavy oil reservoirs began, it was assumed that the primary production mechanisms were sand compaction, solution gas drive and thermal effects due to steam cyclic stimulation which improves oil mobility. However, an unexpectedly high cold production lead to research of the drive mechanisms to explain the special production performance. Similar behavior has been observed in the Lloydminster area of Canada. Despite considerable speculation, a number of authors have studied foamy oil behavior and some research has recently been done, yet the mechanism leading to this behavior still remains to be successfully explained. Reservoir properties that were proposed to explain the behavior in the OB and in Canada include unusually high sand permeability and/or critical gas saturation. In Canada, high critical gas saturation is now an accepted property of some reservoirs, the so called Foamy Oil reservoirs. However, a monitoring field program of sand compaction and land subsidence did not show any evidence that this mechanism has taken place in the Hamaca Area. None of these proposed properties and mechanisms are consistent with field observations. On the other hand, numerical models showed high uncertainty when trying to match the reservoir production pressure behavior. As a consequence, a research program was designed as part of an integrated reservoir study. It included a production behavior analysis, an experimental program for fluid/porous media characterization through conventional and nonconventional PVT tests, and solution gas drive experiments at research centers of Venezuela (INTEVEP), Canada (PRI-CMG) and USA (LAB).
P. 639
Simulation of Injection Water Supply Wells in Central Arabia
Authors: Nasr-El-Din H. A. , Rosser H. R. , Hopkins J. A. 
Published: December 2007

Abstract
Seventeen wells were drilled in an aquifer to supply water for injection in an oil field in central Saudi Arabia. Although these wells produced high volumes of clear water on initial completion, during field start-up most wells produced poor quality water, and only at much reduced rates. A stimulation program to restore the productivity of water supply wells was initiated. The program included injection of 15 wt% HCl along with a friction reducer and a corrosion inhibitor. Samples of all injected and produced fluids were collected to analyze the solid particles present in the samples, and measure the concentration of key ions in the acid returns. The results of these analyses have been used to determine the mechanism by which damage to the wells occurred.
In this paper we present conclusive evidence, drawn from analyses of the returned acid cleaning fluids, which indicates that biomass and microbial corrosion products, produced by active sulfate-reducing bacteria (SRB) populations during shut-in periods, were responsible for much of the damage experienced by these wells. The investigation has highlighted an absolute requirement for an effective downhole SRB control program to prevent subsequent damage to water supply wells which have been restored by the cleaning program.
Based on the results of this investigation, an optimized cleaning procedure which will restore water productivity, and at the same time will minimize casing corrosion, has been developed. This program includes acid additives to minimize precipitation of calcium sulfate, elemental sulfur and ferric hydroxide, which can damage the formation and reduce the productivity of water supply wells.
Cost Benefits Derived from the Implementation of a Corrosion Management System
Authors: Attwood P. A. , Bool K. K. , Van Gelder K. 
Published: December 2007

Abstract
In order to combat the rising costs attributed to corrosion in PDO's oil production operations, an initiative was undertaken to develop a Corrosion Management System. A description is given of the functionality of the developed system, Pacer-CM, which has been designed to capture all monitored data deemed relevant to corrosion control for all facilities exposed to a corrosion risk. The financial benefits that have been accrued in the relatively short time frame that the system has been operational are also discussed.
Fluviatille Reservoir Modelling – Integration of Geological, Seismic and Production Data with Stochastic Modelling Techniques for Reservoir Management Optimisation
Authors: Silva A. Costa e , Silva F. P. , Soares A. , Weber K. J. 
Published: December 2007

Abstract
Fluvial sandstones are important hydrocarbon reservoirs in the Middle East and world-wide. However the significant lithological heterogeneities and lateral continuity are main limitations when considering reservoir development plans. Furthermore low net-to-gross sequences are usually beyond seismic resolution as only the stacked sandstones of the incised valley fills provide sufficient acoustic contrast to be recognised seismically. Major problems are usually encountered in defining sand volume, connectivity and recoverable hydrocarbons. All these factors are critical when considering field management plans and are related directly with the definition of complex spatial configurations, constrained to geological information usually via a genetic classification scheme.
When insufficient information is available the optimisation of modelling procedures becomes of utmost importance. In those cases the integration of all the available information with stochastic modelling techniques minimises uncertainties in the input values used as reservoir parameters for building predictive models for the distribution of sandbodies, flow properties and recoverable hydrocarbons.
This study concerns the development of an integrated methodology for modelling fluvial sequences presenting low net-to-gross ratios, in which channel belts are enclosed within flood plain fines. The main steps are: i) characterisation of channel main morphological features from well data and outcrop analysis; ii) stochastic simulation of channels geometry conditioned to local anisotropy of meander orientations (dipmeter measures, FMI/FMS, etc.); iii) pos-processing of the stochastic images of the meander-belt structures using a morphological filter to clean noisy features.
An example from the Middle East is presented in order to illustrate the application of the methodology to a typical fluvial environment presenting complex characteristics.
Developments in Multiphase Metering
Authors: Ribeiro Alvaro 
Published: December 2007

ABSTRACT
In this paper we will present new techniques for measuring three phase flow using the following approaches:
– Homogenisation – In line separation, metering and recombination – In line metering; leave as it is
Within the concept of "In line metering; leave as it is" the use of the Multi Capacitance technique or the Combination of dissimilar flow sensors and energy absorption probes, are with some limitations in a fast track to be considered proven technologies.
Latest field test results of the Multi Capacitance technique will be presented.
Fault Interpretation and Fracture Morphology: A Case Study of Jurassic Carbonate Reservoir in El-Bunduq Oil Field, Offshore Abu Dhabi and Qatar
Authors: Honda Nobuyuki , Mohamed Kamel Mahmood Abouelenein , Loader Chris , Akbar Mahmood 
Published: December 2007

Abstract
A simple salt dome and a few sets of graben faults characterize the structure of the El Bunduq Oil Field, where the Jurassic carbonates comprise the main reservoirs. The understanding of faults and fractures deepened after the 3D seismic survey and the drilling of a horizontal well in 1994-1995. The present study principally deals with the fault geometry mainly based on 3D seismic and the properties of fractures based on borehole image logs. Discussions shall be further extended to sealingness of fault planes, relationship between faults and fractures, and a role of fractures in the drainage systems of hydrocarbons.
Effect of Inorganic Gases on Reservoir Quality, Abu Dhabi Onshore Structures
Authors: Ayoub Mohamed R. , EnNadi Ibrahim M. , Abdulla Azhari A. 
Published: December 2007

Abstract
Some Palaeozoic (Permian) and Mesozoic reservoirs of Abu Dhabi contain variable amounts of inorganic gases, namely hydrogen sulphide, carbon dioxide, and nitrogen. The vertical and horizontal distribution of these gases vary considerably owing to various factors such as the proximity to the source area, hydrocarbon and other basinal fluids migration pathways, burial depth, variation in geothermal gradient, and in the case of hydrogen sulphide, the presence of anhydrite. The inorganic gas concentrations together with the impact of their existence on reservoir quality are discussed in this paper.
Integrated petrographic and gas data analyses indicate a proportional relationship between secondary calcite cementation and hydrogen sulphide concentration. Calcite generated as a by-product of the thermo-chemical reaction between anhydrite (CaSO4) and organic gases mainly methane (CH4), played a significant role in damaging the porosity in the studied reservoirs. A direct effect of this phenomenon is witnessed in the Khuff Formation in Abu Dhabi (Worden et al., 1995). This process probably contributed to the marked deterioration of reservoir quality in some of the Thamama zones at NE Bab field. Calcite rich basinal fluids, originated in the Falaaha trough and generated from the thermo-chemical reaction of methane and anhydrite, migrated laterally through the Asab Oolite and then vertically into the Lower Cretaceous reservoirs. This process, among others, has contributed to the deterioration of the petrophysical characteristics of these reservoirs.
Carbon dioxide, which is dissolvative, in formation water, created a weak acid that provided additional microporosity. In the Habshan Formation, the CO2 content increases with depth and as a consequence, the porosity in these reservoirs was enhanced due to leaching caused by the dissolved carbon dioxide.
Integration of 3D Seismic Data Into Reservoir Models Using Geostatistics
Authors: Silva A. Costa , Guerreiro L. , Maciel C. , Ramos L. , Guerra R. , Soares A. 
Published: December 2007

Abstract
In complex oil reservoir a detailed characterisation of lateral variations of lithologies and reservoir properties is essential to optimise field development plans and maximise effective recovery of in-place hydrocarbons.
This paper illustrates how a flexible and multidisciplinary methodology can integrate 3D seismic data with geological and petrophysical information in order to enhance the identification of lithologies, quantify bed thickness, perform vertical zonation, establish the continuity and extend of reservoir zones and predict inter-well properties. 3D Seismic data (amplitudes, interval travel times between events, frequency variations, etc.) are correlated with porosity, fluid type, lithologies and net-pay thickness via the use of geostatistical models. A methodology of stochastic simulation is proposed in order to integrate 3D seismic data (amplitudes) and well data (rock-types) through a multisteps conditioning approach. This approach is as follows:
♦ In each grid node, local conditional probability distribution functions are derived from the global calibrated regressions between seismic amplitudes (RMS-Response Phase Map) and well petrophysical properties. A probability field simulation of primary variables is performed, based on these cumulative probability density functions (cpdf). ♦ In a second step the simulation is conditioned to the well data petrophysical values.
3D Survey Design, Acquisition, and Processing for Reservoir Characterization and Monitoring
Authors: Lansley R. Malcolm , Fleming Mike , King Geoffrey A. , Will Bob 
Published: December 2007

Abstract
In the early days of 3D seismic, there was a common tendency to classify the objectives of any survey as being either "structural" or "stratigraphic". The parameters selected for the survey design and data acquisition, and those selected for the subsequent data processing, would often change depending upon the classification. If we look at the interpretation of most 3D surveys we can see that this simple classification is not justified. More and more information is extracted from every data set, and then used to improve our understanding of the reservoir. Most 3D surveys collected today are, to a greater or lesser extent, being used as important components in reservoir characterization studies. The objectives of such studies being the integrated understanding of the reservoir's structure, the lithology, and the pore fluids.
Although significant time and effort is usually spent trying to achieve the optimum technical design for these 3D surveys, there are always compromises because of cost, time and other influences such as environmental impact. The technology available for recording and processing seismic data in a cost effective and timely manner often results in limitations in the results which are provided to the interpreter. It is important for the interpreter to understand the nature and relative importance of these limitations. In recent years, an increasing number of time lapse (4D) seismic surveys have been acquired. In these cases the seismic data is the subject of additional objectives i.e. the monitoring of fluid movements through the reservoir and the subsequent use of this information to update the reservoir simulation model. These reservoir monitoring studies present some additional requirements on both acquisition and data processing systems, if the studies are to be successful.
This paper discusses some of the data acquisition and data processing issues which must be considered when acquiring seismic surveys for reservoir characterization and monitoring.
Applications of a New Production Logging Tool to Locate Fluid Entries and Borehole Flow Imaging
Authors: Boyle Keith , Bustani Aresh 
Published: December 2007

Abstract
Production Logging examples including a new sensor which provides four independent water holdup measurements are presented. Combined with the conventional Production Logging string, the Floview(†) Tool, significantly improves downhole flow diagnosis in vertical and deviated wells. Fluid images from four symmetrically positioned probes provide information on flow regimes and phase segregation. The tool has specific applications in horizontal wells for water holdup determination in segregated flow conditions.
The examples provided present surveys from five wells conducted in one of the Middle East reservoirs, where the objectives were not only to identify the main water and gas entry zones into the wellbore, but also to determine the quantitative downhole flow profile.
The Ultimate Line Drive Using Multilateral Wells: Plans for 200 km of Horizontal Hole in the Saih Rawl Shuaiba Reservoir, PDO
Authors: Seeberger F. C. , Rothenhoefer H. W. , Akinmoladun O. J. 
Published: December 2007

Abstract
The Shuaiba Formation at Saih Rawl, a tight carbonate reservoir in Central Oman, was not fully exploited after discovery for over 20 years with only three vertical wells producing at marginal rates. Exclusive use of horizontal and multilateral well technology has given the field a new life resulting in immediate full field development. A well lay out was chosen to accomplish an ideal line drive. This waterflood project involves the injection of produced water through multilateral horizontal injectors to provide pressure support. Two or three parallel legs are placed below the OWC to achieve bottom water sweep. The oil is produced through single or dual horizontal wells drilled along top reservoir equally spaced between the injectors at a maximum oil column height of 32 m. The wells are drilled at a spacing of 125 m lateral and some 30 m vertical distance between producers and injectors. Individual laterals are more than 2 km long. As a result of this development plan ultimate recovery is expected to rise tenfold from 3.9 (depletion only) to 39 min m3.