Current practices in energized treatments, using gases and foams, remain rudimentary in comparison to other fracturing fluid technologies. None of the available 3D fracturing models for incompressible water-based fluids have been able to capture the thermal and compositional effects that are important when using energized fluids, as their constitutive equations assume single-phase, single-component, incompressible fluid flow. These models introduce a bias in fluid selection because they do not accurately capture the unique behavior of energized fluids. The lack of modeling tools specifically suited for these fluids has hindered their design and field implementation. This work uses a fully compositional 3D fracturing model to answer some of the questions surrounding the design of energized treatments. The new model is capable of handling any multi-component mixture of fluids and chemicals. Changes in fluid density, composition, and temperature are predicted using an energy balance equation and an equation of state. A wellbore model, which relates the surface and bottomhole conditions, determines the pumping requirements. Fracture performance is assessed by a fractured well productivity model that accounts for damage in the invaded zone and finite fracture conductivity. The combination of the fracture, productivity, and wellbore models forms a standalone simulator that is suitable for designing and optimizing energized treatments. The simulator offers a wide range of capabilities, making it suitable for many different applications ranging from hydraulic fracturing to long-term injections for enhanced oil recovery, well clean-up, or carbon sequestration purposes. The model is applicable to any well configuration: vertical, deviated, or horizontal. The resolution of the full 3D elasticity problem enables us to propagate the fracture across multiple layers, where height growth is controlled by the vertical distribution of the minimum horizontal stress. We conducted several sensitivity studies to compare the fracture propagation, productivity, and pumping requirements of various fluid candidates in different reservoirs. The results show that good proppant placement and high fracture conductivities can be achieved with foams and gelled fluid formulations. Foams provide a wide range of viscosities without using excessive amounts of gelling agents. They also provide superior fluid-loss control, as the filter-cake is supplemented by the presence of gas bubbles that reduce liquid-flow into the porous medium. CO₂, LPG, and N₂ expand significantly (by 15% or more) as the reservoir heats the fluid inside the fracture. These fluids show virtually no damage in the invaded zone, which is a significant improvement upon water-based fluids in reservoirs that are prone to water blocking. These results, however, are contingent on an accurate fluid characterization supported by experimental data; therefore, our work advocates for complementary experimental studies on fluid rheology, proppant transport, and fluid leak-off. A comprehensive sensitivity study over a wide range of reservoir conditions identified five key reservoir parameters for fluid selection: relative permeability curve, initial gas saturation, reservoir pressure, changes to rock mechanical properties, and water-sensitivity. Because energized fluids provide similar rheology and leak-off behaviors as water-based fluids, the primary design question it to evaluate the extent of the damaged zone against costs, fluid availability, and/or safety hazards. If the fluid-induced damage is acceptable, water-based fluids constitute a simple and attractive solution; otherwise, energized fluids are recommended. Notably, energized fluids are well-suited for reservoirs that are depleted, under-saturated, and/or water-sensitive. These fluids are also favorable in areas with a limited water supply. As water resources become constrained in many areas, reducing the water footprint and the environmental impact is of paramount concern, thereby making the use of energized treatments particularly attractive to replace or subsidize water in the fracturing process. / text

Two-phase flow occurs during the production of oil and gas in the wellbores. Modeling this phenomenon is important for monitoring well productivity and designing surface facilities. Since the transient time period in the wellbore is usually shorter than reservoir time steps, stabilized flow is assumed in the wellbore. As such, semi-steady state models are used for modeling wellbore flow dynamics. However, in the case that flow variations happen in a short period of time (i.e., a gas kick during drilling) the use of a transient two-phase model is crucial. Over the last few years, a number of numerical and analytical wellbore simulators have been developed to mimic wellbore-reservoir interaction. However, some issues still remain a concern in these studies. The main issues surrounding a comprehensive wellbore model consist of fluid property calculations, such as black-oil or compositional models, governing equations, such as mechanistic or correlation-based models, effect of temperature variation and non-isothermal assumption, and methods for coupling the wellbore to the reservoir. In most cases, only standalone wellbore models for blackoil have been used to simulate reservoir and wellbore dynamic interactions. Those models are based on simplified assumptions that lead to an unrealistic estimation of pressure and temperature distributions inside the well. In addition, most reservoir simulators use rough estimates for the perforation pressure as a coupling condition between the wellbore and the reservoir, neglecting pressure drops in the horizontal section. In this study, we present an implementation of a compositional, pseudo steady-state, non-isothermal, coupled wellbore-reservoir simulator for fluid flow in wellbores with a vertical section and a horizontal section embedded on the producing reservoir. In addition, we present the implementation of a pseudo-compositional, fully implicit, transient two-fluid model for two-phase flow in wellbores. In this model, we solve gas/liquid mass balance, gas/liquid momentum balance, and two-phase energy equations in order to obtain the five primary variables: liquid velocity, gas velocity, pressure, holdup and temperature. In our simulation, we compared stratified, bubbly, intermittent flow effects on pressure and temperature distributions in either a transient or steady-state condition. We found that flow geometry variation in different regimes can significantly affect the flow parameters. We also observed that there are significant differences in flow rate prediction between a coupled wellbore-reservoir simulator and a stand-alone reservoir simulator, at the early stages of production. The outcome of this research leads to a more accurate and reliable simulation of multiphase flow in the wellbore, which can be applied to surface facility design, well performance optimization, and wellbore damage estimation. / text

It has been known that volatile oil and gas condensate reservoirs cannot be modeled accurately with conventional black-oil models. One variation to the black-oil approach is the modified black-oil (MBO) model that allows the use of a simple, and less expensive computational algorithm than a fully compositional model that can result in significant timesaving in full field studies. The MBO model was tested against the fully compositional model and performances of both models were compared using various production and injection scenarios for a rich gas condensate reservoir. The software used to perform the compositional and MBO runs were Eclipse 300 and Eclipse 100 versions 2002A. The effects of black-oil PVT table generation methods, uniform composition and compositional gradient with depth, initialization methods, location of the completions, production and injection rates, kv/kh ratios on the performance of the MBO model were investigated. Vertical wells and horizontal wells with different drain hole lengths were used. Contrary to the common belief that oil-gas ratio versus depth initialization gives better representation of original fluids in place, initializations with saturation pressure versus depth gave closer original fluids in place considering the true initial fluids in place are given by the fully compositional model initialized with compositional gradient. Compared to the compositional model, results showed that initially there was a discrepancy in saturation pressures with depth in the MBO model whether it was initialized with solution gas-oil ratio (GOR) and oil-gas ratio (OGR) or dew point pressure versus depth tables. In the MBO model this discrepancy resulted in earlier condensation and lower oil production rates than compositional model at the beginning of the simulation. Unrealistic vaporization in the MBO model was encountered in both natural depletion and cycling cases. Oil saturation profiles illustrated the differences in condensate saturation distribution for the near wellbore area and the entire reservoir even though the production performance of the models was in good agreement. The MBO model representation of compositional phenomena for a gas condensate reservoir proved to be successful in the following cases: full pressure maintenance, reduced vertical communication, vertical well with upper completions, and producer set as a horizontal well.

This research seeks to elucidate the role of relatively large-scale ceramic productionindustries located at the Classic period center of Matacapan in the Sierra de los Tuxtlas, SouthernVeracruz, Mexico. Arnold et al. (1993) have suggested that the specialized production atComoapan, the largest production locality at Matacapan, was oriented toward supplying theregion with ceramics. This production locality overwhelmingly specialized in manufacturingone standardized ware, Coarse Orange, into necked and neckless jars, which are found in manyparts of the region.The compositional techniques of instrumental neutron activation analysis (INAA) andpetrography were employed to investigate the distribution of this ware. Control groups weresampled from known production loci at Matacapan. The data does reveal strong evidence thatCoarse Orange was traded from Matacapan to other sites in the Tuxtlas. Comoapan was themost likely producer for this trade. Equally as important, this research yielded several differentcompositional groups, which indicates sites that either did not interact with Matacapan to procurethis ware, or who produced their own varieties of Coarse Orange. While Matacapan seems tohave had economic influence over parts of the Tuxtlas, the distribution of non-Matacapancompositional groups is useful to delineate areas of the Tuxtlas who display minimal economicinteraction with this regional center.

Nigel (Henry) Butterley (b. 1935) is recognised as one of Australia??s foremost contemporary composers. His works span most compositional genres. By making a case for the value of sketch study in the process of musical analysis, the principal purpose of this thesis is to augment understanding of Butterley??s music and in particular, his compositional processes and procedures through the various stages of the genesis of a composition, from the sketch to final score. Butterley??s string quartets, composed between the years 1965 to 2001 provide the basis for this study; these works are contextualised and examined to illustrate his approach to composition in microcosm and also his individual style within the genre of string quartet writing. This study focuses on the examination of preliminary sketches, drafts and holographs, as well as the scores of the completed works. Initially, analysis is based on preliminary sketches; this will be augmented by a formal analysis of the completed works. Traditionally, formal analysis deals with the final product, something that has been created, and in a sense, views a work retrospectively. Sketch study, in contrast, examines the work as it is being created and is concerned with the attendant compositional issues and choices available to the composer and the processes followed as he or she creates the composition. The current work will identify significant common features in all the string quartets, and will trace Butterley??s compositional trajectory through these works demonstrating that individual characteristics of Butterley??s style, emergent as early as 1965, continued to be utilised in 1995 and remain present in the Bagatelle of 2001. That these characteristics remain present in a minut?? is significant, in that the Bagatelle may be seen as a microcosm of the writing style evident in his larger works. This thesis will demonstrate that sketch study and formal analysis may interact in order to provide a more comprehensive interpretation of a composer??s work and enrich the understanding and appreciation of the compositional process and the final product, ultimately impacting on the realisation of a composer??s work through performance.

This study investigated the discrimination between sources of the semi-precious mineral, nephrite, by a targeted microanalytical determination of the elemental composition, including the trace elements. Nephrite specimens were collected from two significant nephrite sources in New Zealand, namely the Westland and Wakatipu fields, and combined with donated specimens from the Southland field to complete a representative collection of New Zealand nephrite. A small number of nephrite specimens were donated from the South Westland nephrite field and from foreign sources. Representative fragments of these specimens were analysed by electron microprobe analysis (EMPA) for major elements and by laser ablation inductively coupled plasma mass spectrometry (LA-ICP-MS) for trace elements. The data obtained by the analytical procedure were treated within a compositional data (CoDa) framework of statistical analysis that focuses on the relative sizes of the components in the data set. The data were transformed under the guidelines of the CoDa framework, where appropriate, and the transformed data were treated with standard statistical methods for exploratory data analysis, dimension reduction and discriminant analysis. Advances were made to the Hotelling’s method for comparison of multivariate means by incorporating a permutation evaluation step. This permutation method removes the requirement for multivariate normality, and it also allows comparisons to be made when there are many more variables than observations, as is often the case when objects are being characterized using elemental data. The strategy used in this study showed that it is possible to discriminate between sources of nephrite at both an intra- and inter-source level within New Zealand. In addition, an exploratory investigation showed that New Zealand nephrite could be differentiated from the few nephrite specimens from foreign sources that were available for comparison. Recommendations are made for the protection of the New Zealand nephrite resource and for casework, based on the results obtained in this study.

This study investigated the discrimination between sources of the semi-precious mineral, nephrite, by a targeted microanalytical determination of the elemental composition, including the trace elements. Nephrite specimens were collected from two significant nephrite sources in New Zealand, namely the Westland and Wakatipu fields, and combined with donated specimens from the Southland field to complete a representative collection of New Zealand nephrite. A small number of nephrite specimens were donated from the South Westland nephrite field and from foreign sources. Representative fragments of these specimens were analysed by electron microprobe analysis (EMPA) for major elements and by laser ablation inductively coupled plasma mass spectrometry (LA-ICP-MS) for trace elements. The data obtained by the analytical procedure were treated within a compositional data (CoDa) framework of statistical analysis that focuses on the relative sizes of the components in the data set. The data were transformed under the guidelines of the CoDa framework, where appropriate, and the transformed data were treated with standard statistical methods for exploratory data analysis, dimension reduction and discriminant analysis. Advances were made to the Hotelling’s method for comparison of multivariate means by incorporating a permutation evaluation step. This permutation method removes the requirement for multivariate normality, and it also allows comparisons to be made when there are many more variables than observations, as is often the case when objects are being characterized using elemental data. The strategy used in this study showed that it is possible to discriminate between sources of nephrite at both an intra- and inter-source level within New Zealand. In addition, an exploratory investigation showed that New Zealand nephrite could be differentiated from the few nephrite specimens from foreign sources that were available for comparison. Recommendations are made for the protection of the New Zealand nephrite resource and for casework, based on the results obtained in this study.

This study investigated the discrimination between sources of the semi-precious mineral, nephrite, by a targeted microanalytical determination of the elemental composition, including the trace elements. Nephrite specimens were collected from two significant nephrite sources in New Zealand, namely the Westland and Wakatipu fields, and combined with donated specimens from the Southland field to complete a representative collection of New Zealand nephrite. A small number of nephrite specimens were donated from the South Westland nephrite field and from foreign sources. Representative fragments of these specimens were analysed by electron microprobe analysis (EMPA) for major elements and by laser ablation inductively coupled plasma mass spectrometry (LA-ICP-MS) for trace elements. The data obtained by the analytical procedure were treated within a compositional data (CoDa) framework of statistical analysis that focuses on the relative sizes of the components in the data set. The data were transformed under the guidelines of the CoDa framework, where appropriate, and the transformed data were treated with standard statistical methods for exploratory data analysis, dimension reduction and discriminant analysis. Advances were made to the Hotelling’s method for comparison of multivariate means by incorporating a permutation evaluation step. This permutation method removes the requirement for multivariate normality, and it also allows comparisons to be made when there are many more variables than observations, as is often the case when objects are being characterized using elemental data. The strategy used in this study showed that it is possible to discriminate between sources of nephrite at both an intra- and inter-source level within New Zealand. In addition, an exploratory investigation showed that New Zealand nephrite could be differentiated from the few nephrite specimens from foreign sources that were available for comparison. Recommendations are made for the protection of the New Zealand nephrite resource and for casework, based on the results obtained in this study.

This study investigated the discrimination between sources of the semi-precious mineral, nephrite, by a targeted microanalytical determination of the elemental composition, including the trace elements. Nephrite specimens were collected from two significant nephrite sources in New Zealand, namely the Westland and Wakatipu fields, and combined with donated specimens from the Southland field to complete a representative collection of New Zealand nephrite. A small number of nephrite specimens were donated from the South Westland nephrite field and from foreign sources. Representative fragments of these specimens were analysed by electron microprobe analysis (EMPA) for major elements and by laser ablation inductively coupled plasma mass spectrometry (LA-ICP-MS) for trace elements. The data obtained by the analytical procedure were treated within a compositional data (CoDa) framework of statistical analysis that focuses on the relative sizes of the components in the data set. The data were transformed under the guidelines of the CoDa framework, where appropriate, and the transformed data were treated with standard statistical methods for exploratory data analysis, dimension reduction and discriminant analysis. Advances were made to the Hotelling’s method for comparison of multivariate means by incorporating a permutation evaluation step. This permutation method removes the requirement for multivariate normality, and it also allows comparisons to be made when there are many more variables than observations, as is often the case when objects are being characterized using elemental data. The strategy used in this study showed that it is possible to discriminate between sources of nephrite at both an intra- and inter-source level within New Zealand. In addition, an exploratory investigation showed that New Zealand nephrite could be differentiated from the few nephrite specimens from foreign sources that were available for comparison. Recommendations are made for the protection of the New Zealand nephrite resource and for casework, based on the results obtained in this study.

Este trabalho apresenta uma reflexão sobre a memória do processo composicional e uma análise das características apreendidas pela consciência da compositora, através da música. As composições, que são o principal objeto de reflexão neste memorial, tiveram como premissa estética o conceito de sombra, o qual inspirou as tomadas de decisão. O procedimento primordial, para a elaboração das peças, constitui-se a partir da ação, a qual é tomada como ponto de partida para a caracterização e a identidade expressiva da composição, fundamentalmente relacionada à performance. A análise é amparada pela Fenomenologia da Música, em autores como Schutz (1976) e Clifton (1976), e se concentrou nas temporalidades encontradas nas composições, valendo-se das proposições de Kramer (1988), acerca dos tipos de passagem do tempo (Tempo Linear e Tempo Não-Linear). Estes tipos são relacionados aos objetos ideais do pensamento da autora, especialmente aqueles originados na experiência musical. Imagens e sonoridades integram uma moldura de referência que agrupa os conteúdos da memória. Desta forma, sonoridades, ações e memórias, são tomadas como aspectos constituintes do fenômeno musical e composicional. / This paper presents a reflection on the memory of the compositional process and an analysis of the characteristics apprehended from composer’s consciousness, through the music. The compositions, which are the main object of reflection in this memorial, had the concept of shadow as its aesthetic premise, which inspired the decision-making. The fundamental procedure for the preparation of compositions, it constitutes from the action, which is taken as a starting point for characterizing the composition and the musical identity, mainly related to performance. The analysis is supported by Phenomenology of Music, from authors like Schutz (1976) and Clifton (1976), and is focused on temporalities found in music, using the Kramer (1988) propositions about the kinds of time (Linear Time and Nonlinear Time). These kinds are related to ideal objects of autoress’ thought, especially those originated in musical experiences. Images and sonorities are members of a frame of reference that groups the memory contents. Thus, sonorities, memories and actions are taken as aspects that constitute the musical and compositional phenomenon.