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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
61

A petrographic and geochemical characterization and the evaluation of the exploration potential for nickel sulfides in several mafic-ultramafic intrusive complexes in Newfoundland /

Collins, Patrick G., January 2007 (has links)
Thesis (M.Sc.)--Memorial University of Newfoundland, 2007. / Includes bibliographical references (leaves 328-335). Also available online.
62

The Forsterite-Anorthite-Albite system at 5 kb pressure

Rahilly, Kristen Elizabeth. January 2010 (has links)
Honors Project--Smith College, Northampton, Mass., 2010. / Includes bibliographical references (p. 44-45).
63

Rare-earth elements in USGS rocks SCo-1 and STM-1, basalts from the Servilleta and Hinsdale formations, and rocks from the Stillwater and Muskox intrusions

Kosiewicz, Stanley T. January 1973 (has links)
Thesis (Ph. D.)--University of Wisconsin--Madison, 1973. / Typescript. Includes abstract and vita. eContent provider-neutral record in process. Description based on print version record. Includes bibliographical references (leaves 132-135).
64

Architecture and sedimentology of slope channel fills : an outcrop- and subsurface-based study

Li, Pan January 2017 (has links)
Slope channel systems represent significant but highly variable deep-water stratigraphic features and reservoir targets. Variations in architecture and component facies can take place along strike, depositional dip and stratigraphically. A better understanding of these variations permits improved sedimentological and architectural models. By integrating two outcrops (San Clemente, California and Baja California, Mexico) and one subsurface example (offshore Nile Delta), this study provides an opportunity to investigate cross-channel asymmetry, stratigraphic evolution and variability, vertical facies trends, and controls of slope channel systems. This study demonstrates that cross-channel asymmetry in facies and architecture is a lithology- and scale-independent feature, and preferentially occurs at channel bends and in the upper part of slope channel systems. Facies and architectural asymmetry are generally expressed as amalgamated, coarser-grained deposits displaced to the steeper channel edge (outer bend), and finer-grained deposits dominate towards the gentler channel edge (inner bend). A comparison of the systems exposed in Mexico and buried in the subsurface reveals a similar evolutionary trend, from initial sediment erosion/bypass, through early-stage laterally amalgamated channels, late-stage sinuous channels with levees/terraces, and final abandonment. However, pronounced variations exist in the late stage (e.g., presence or absence of lobes), and abandonment stage (e.g., presence or absence of MTDs plugging and channel avulsion). Additionally, for the first time, this study quantitatively demonstrates that early-stage and late-stage architectural elements are characterized by distinct patterns in preferred vertical facies transitions, based on Markov chain analysis of vertical successions. This study also suggests that both extrabasinal factors (e.g., relative sea-level) induced flow energy cycles and intrabasinal factors (e.g., folding and faulting, MTDs, channel bends) can exert a significant control on the architecture and/or evolution of slope channel systems.
65

Languages in Contact: Polish and English

Beauchamp, Hanna O. (Hanna Olga) 08 1900 (has links)
The purpose of this study was to examine the Polish language of immigrants who came to the United States during or after World War II and to test two related hypotheses: 1. Speakers of Polish use a number of lexical intrusions. 2. Lexical intrusions differ in scope depending on whether those speakers had immigrated with minimal education or they received at least 12 years of schooling prior to their immigration. The study was conducted in the Dallas-Fort Worth area in January and February of 1990. The sample consisted of 16 informants whose interviews were recorded and analyzed in terms of lexical borrowings, cultural branches, and parts of speech. Findings supported the two hypotheses.
66

Effect of dolerite intrusions on coal quality in the Secunda coal fields of South Africa

Bussio, John Paul 07 November 2012 (has links)
The coalfields of South Africa contain numerous dolerite intrusions, which are believed to have affected the quality of the surrounding coal by a thermal process, controlled by the size of the magmatic body. Data gathered from a working coalfield in Secunda, South Africa, suggest that the relationship between intrusive sills and coal is complex and factors other than intrusion width must be considered in relation to the contact metamorphic effect. The study area contains multiple dolerite intrusions of Karoo age, separated according to their geometric relationship to the local coal seams. Three intrusions were selected for detailed study. The three dolerite bodies, namely the DO4, DO8 and DO10 dolerites, occur as sills intruded close to the main coal seam of the area. The dolerite sills have identical mineralogy and can only be distinguished through textural variations in thin section. Coal quality data was obtained from Sasol Mining Secunda and used to investigate the presence or absence of a change in coal quality relative to dolerite proximity. Reduction in coal quality was defined using three main proximate analysis values, termed Ash, Volatile content (Vols) and Dry Ash Free Volatile (DAFV) in the coal industry. These parameters were used to determine the extent of any effect deleterious to coal quality induced by the intrusion of the dolerite sills. The resultant investigation showed no correlation between the position and thickness of the dolerites, and a change in coal quality (as measured by proximate analysis). In the absence of a linear relationship between coal quality and dolerite proximity, two processes are proposed to explain the absence of the contact metamorphic effects expected from previous studies: -Dolerite emplacement dynamics may influence the size of the metamorphic aureole produced by an intrusion, and invalidating intrusion size as a measure of thermal output, - Hydrothermal fluids mobilised by the dolerite intrusions, either from the country rock or the intrusion itself may percolate through the coal and act as the metamorphic agent responsible for changing coal quality, by dissolving the volatile components of the coal and transporting them to other locations These two processes are sufficient to explain the lack of a clear “metamorphic effect” related to the dolerite intrusions. Copyright / Dissertation (MSc)--University of Pretoria, 2012. / Geology / unrestricted
67

Modélisation de la formation de motifs périodiques dans un système eutectique binaire formant un corps igné

Ghaoui, Jade January 2015 (has links)
Les oscillations en composition et taille des grains peuvent parfois être générées dans les intrusions magmatiques, produisant des motifs caractéristiques à l’échelle du centimètre au mètre sous forme de couches cycliques. Il est essentiel de comprendre l’origine de ces motifs afin d’établir les circonstances géologiques de formation de ces corps. Nous travaillons avec l’hypothèse que ces motifs sont le résultat d’un processus d’auto- organisation non linéaire selon lequel l’interaction entre la dynamique de cristallisation et la diffusion cause la ségrégation des minéraux selon leur nature et leur taille. Ce mécanisme est semblable à celui à l’origine des bandes de Liesegang et mène à des caractéristiques comparables, telles qu’une progression géométrique de la position des bandes. Dans le but d’obtenir une description plus complète du processus de formation des motifs périodiques dans le contexte d’un système magmatique eutectique binaire en contact avec une roche- mère plus froide, nous présentons un modèle numérique en une dimension de nucléation et croissance qui généralise les modèles précédents. Notre modèle inclut une correction tenant compte de l’effet de la porosité sur la tortuosité, ainsi que le mûrissement d’Ostwald, facul- tativement. La solidification est contrôlée par des paramètres clés déterminant l’émergence du motif. De plus, en utilisant une géométrie sphériquement symétrique, notre modèle peut être appliqué à la formation de granites orbiculaires.
68

Maladaptive appraisals and intrusive thoughts associated with obsessive compulsive disorder: A semiidiographic approach.

Hutchinson, Geoffrey 08 1900 (has links)
This project investigated the metacognitive strategies used to appraise obsessive thoughts employed by individuals with different anxiety symptoms. Two hundred eighty-seven undergraduate students completed two repertory grids and three anxiety scales. The repertory grids respectively examined the appraisal process of intrusive thoughts both from the perspective of the rater and the rater's imagined average person. Variables quantified from the rep grid related to the construal process of raters' own intrusions, failed to demonstrate robust differences between OCD, non-OCD anxious, and non-anxious individuals. However, it appears that anxious individuals, not just those with OCD, use metacognitive strategies to suppress rigid constructions under perceived social evaluation. Future studies may wish to use related grid variables to explore the relation between obsessions and social anxiety.
69

Plutonism and tectonic evolution of the Ras Gharib segment of the northern nubian shield, Egypt

Abdel-Rahman, Abdel-Fattah Mostafa January 1986 (has links)
No description available.
70

The intrusive rocks of the Hepburn metamorphic-plutonic zone of the central Wopmay Orogen, N.W.T. /

Lalonde, André E. January 1986 (has links)
No description available.

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