Description pétrographique des formations .

Le diagnostic du SAGE Loire au niveau de la plaine du Forez (42) relate une dégradation du potentiel hydrogéologique et une pollution des nappes superficielles par les nitrates et les pesticides. Ces problèmes nécessitent une gestion durable et équilibrée de la ressource en eau. Une partie de la demande en eau est assurée par la ressource souterraine. Les eaux souterraines exploitées sont : les eaux des formations alluviales superficielles pour l'irrigation et l'AEP ; et les eaux minérales des niveaux aquifères profonds du bassin sédimentaire sous-jacents aux alluvions pour le thermalisme et de mise en bouteille.La synthèse des connaissances disponibles a révélé des insuffisances dans la description des aquifères superficiels. En effet, elles ne permettent pas d'appréhender comment fluctue la ressource dans le temps et ne prennent pas en compte l'origine de la recharge des aquifères superficiels. Ainsi, le travail de thèse se focalise sur ces deux points particuliers :- l'identification du fonctionnement transitoire des aquifères est abordée par caractérisation physique des écoulements s'appuyant sur l'analyse de 4 points de suivi piézométrique permanent et la modélisation numérique des écoulements permettant de reproduire les fluctuations piézométriques observées.- l'origine de la recharge des aquifères alluviaux est abordée par caractérisation géochimique des écoulements (analyses en ions majeurs et isotopes δ180, δ2H, δ13C et A14C). Cette approche a mis en évidence des apports d'eaux profondes alimentant localement les aquifères superficiels.La méthodologie proposée, couplée physique et géochimie, permet de mieux préciser la vulnérabilité des aquifères investigués, en vue d'une meilleure gestion future.

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The "slot-drill" completion method, which utilizes a mechanically cut high-conductivity "slot" in the target formation created using a tensioned abrasive cable, has been proposed as an alternative stimulation technique for shale-gas and other low/ultra-low permeability formations. This thesis provides a comprehensive numerical simulation study on the "slot drill" completion technique. Using a Voronoi gridding scheme, I created representative grid systems for the slot-drill completion, as well as for the case of a vertical well with a single fracture, the case of a horizontal well with multiple hydraulic fractures, and various combinations of these completions. I also created a rectangular slot configuration, which is a simplified approximation of the actual "slot-drill" geometry, and investigated the ability of this rectangular approximation to model flow from the more complicated (actual) slot-drill configuration(s). To obtain the maximum possible diagnostic and analytical value, I simulated up to 3,000 years of production, allowing the assessment of production up to the point of depletion (or boundary-dominated flow). These scenarios provided insights into all the various flow regimes, as well as provided a quantitative evaluation of all completion schemes considered in the study. The results of my study illustrated that the "slot-drill" completion technique was not, in general, competitive in terms of reservoir performance and recovery compared to the more traditional completion techniques presently in use. Based on my modeling, it appears that the larger surface area to flow that multistage hydraulic fracturing provides is much more significant than the higher conductivity achieved using the slot-drill technique. This work provides quantitative results and diagnostic interpretations of productivity and flow behavior for low and ultra-low permeability formations completed using the slot-drill method. The results of this study can be used to (a) help evaluate the possible application of the "slot-drill" technique from the perspective of performance and recovery, and (b) to establish aggregated economic factors for comparing the slot-drill technique to more conventional completion and stimulation techniques applied to low and ultra-low permeability reservoirs.

The search for the process of electrification in Turkey and how it is materialized in urban space in different scales in indoor and outdoor is the aim of this thesis. Looking for the effects of electrification by means of making a discursive analysis and taking into consideration the objects in substance, concerning the practice itself, and searching for the transformations in the urban space and in urban living are the main objectives of this research. Consequently, popular media will be the main source to look for how electrification was materialized and depicted in the publicity. The popular publications of the period like / magazines, newspapers, films are going to be investigated and re-read in order to decipher how discursive formations were constructed. The intervals of the research period are theheydays of these Modernist discursive formations, mainly the 1930s / starting from 1928 the foundation of Ankara Gas and Electricity Factory which is the symbol and generator of electrification in the new capital Ankara, and ending with 1938 with Mustafa Kemal Atat&uuml / rk&amp / #8217 / s death which can be considered a major turning point in the discursive formations. The theoretical framework of the thesis will take the modernity project in the Turkish Republic, focusing on how collective memory and social identity was constructed at that time.

Thesis (Ph. D.)--University of Texas at Austin, 2000. / Vita. Five folded charts in pocket. Includes bibliographical references (leaves 316-324). Available also in a digital version from Dissertation Abstracts.

The Yoakum Canyon is the largest of the Gulf Coast Eocene erosional gorges and is interpreted as a buried submarine channel. It can be traced for 67 miles from the Wilcox fault zone, which defines the position of the early Eocene shelf edge, nearly to present outcrop. This paper expands on previously published descriptions of the canyon using a more extensive subsurface data base. Decompaction of the canyon shale-fill reveals that original depths of the canyon exceeded 3500 ft (1067 m). Apparent canyon wall slump scarps and a peripheral chaotic zone, interpreted as an incipient slump feature, are comparable to similar features of the late Quaternary Mississippi submarine canyon. The Yoakum canyon formed within the Garwood subembayment to the west of and adjacent to the Middle Wilcox continuation of the Rockdale delta system. Quantitative mapping of facies adjacent to the Yoakum shale indicate the following sequence of events: 1) Muddy, distal deltaic and shelf facies of the lower Middle Wilcox were deposited during a retrogradation. 2) A resurgence of progradation deposited the upper Middle Wilcox deltaic sands atop the unconsolidated, lower Middle Wilcox continental margin muds creating a density inversion which initiated slump failure of the continental margin sediments. 3) Headward erosion of the canyon across the shelf occurred contemporaneously with a subsidence-induced transgression caused by a decrease in the sediment supply. The Yoakum canyon was excavated by a combination of slumping and current scour. 4) The canyon was filled with hemipelagic and prodelta muds. 5) Progradation of the Upper Wilcox (Carrizo) deltaic sands capped the sequence. / text

Aldol reactions are widely used in forming new carbon-carbon bonds. Since the discovery of the aldol condensation, controlling the relative and absolute stereochemistry in aldol chemistry has been a major interest in organic chemistry. Efforts in achieving diastereoselectivity in aldol reactions via chelation of Lewis acids to chiral aldehydes are reviewed. The following chapters discuss the diastereoselectivities of hydrogen-mediated reductive aldol reactions. Herein, a highly diastereoselective reductive aldol coupling reactions with broad substrate scope using rhodium catalysts ligated to (2-furyl)₃P were studied. It was demonstrated that the coupling of enones with alpha-amino aldehydes proceeds with high diastereoselectivity via chelation control. The second topic deals with phosphine-mediated furan ring formation. Derivatives of furan are often found in natural products and therapeutic agents. To provide a more facile route to substituted furans, we have developed a phosphine mediated reductive cyclization of gamma-acyloxy butynoates. In this reaction, phosphine is involved in both the reductive formation of allenyl ketones from acyloxy butynoates and the subsequent catalytic cyclization. / text

This dissertation solves variations of three mathematical problems for autonomous vehicle formations: (1) formation shape control in the plane, (2) robust information architecture design, and (3) formation attitude synchronization. An autonomous vehicle formation is a collection of vehicles, each with computation, communication, sensing, and control capabilities, that cooperate to achieve a common objective. Accelerating advancements are making possible a range of science and engineering applications, such as satellite formations for deep-space imaging, teams of unmanned aircraft for military reconnaissance and surveillance missions, and submarine swarms for oceanic exploration. The ubiquitous potential of these applications is driving theoretical work on autonomous vehicle formations across a range of disciplines. A major theoretical question in the field of control theory, and the main focus of this dissertation, is how the properties of the information architecture (i.e. a mapping of the information flow amongst the agents), relate to the stability properties of the desired shape and orientation under certain control laws. A secondary focus is how to design the information flow so that loss of an agent does not destroy the formation's ability to maintain a desired shape. As a motivating example, a solution to a coordinated standoff tracking problem is presented to demonstrate how an instance of a class of information architectures, which are called persistent and related to rigid graph theory, can be used to achieve a formation objective in a practical scenario involving a team of unmanned aircraft. A generalized formation shape control problem is then solved for a class of persistent architectures. This solution gives only local stability results; global stability is analyzed for a four-agent formation and several open problems are identified. The problem of agent loss is addressed by performing a self-repair operation in the event of agent loss and separately by designing robustness into the information architecture a priori. Finally, a rigid body attitude synchronization problem with communication time delays is solved for a class of information architectures based on spectral graph theory. / text

The research involves mapping of subsurface at a scale of 1:25,000 the top of three geological formations in the Southern Part of Sumatra – the Airbenakat Formation, the top of the Talangakar Formation, and the top of structural basement in the Jambi Trough. Isopach maps of the formations will be constructed. These maps will form the basis of a basin analysis and hydrocarbon source rock assessment of the Jambi Trough using Basin Mod basin modeling software (Rockworks Software). The studies utilize the L. Bogue Hunt Southeast Asia database housed in the Department of Geological Sciences at Ball State University. Seismic record sections, geophysical logs, cutting descriptions, and paleontological reports will provide basic geological data to enable mapping of the three horizons. Although hydrocarbon accumulations are abundant in Central and Southern Sumatra, the nature of the source rocks is only partially understood. The proposed research will map the Airbenakat and Talangakar Formations while identifying the areas of thermally mature source rock is the main goal of the research. This study will identify characteristics which will enable the identification of thermally mature rocks in other regions of Sumatra. The area of the project is located at the Southeastern part of Asia in Indonesia and mainly the Jambi trough located in Southern Sumatra. Generally, the geology and tectonics of this area (Sumatra) is controlled by the subduction of the Indian plate towards the east and beneath the Eurasia plate. / Department of Geological Sciences