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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.
131

The Ellison district: alteration-mineralization associated with a mid-tertiary intrusive complex at Sawmill Canyon, White Pine County, Nevada

Johnson, Lawrence Clinton January 1983 (has links)
No description available.
132

The life history and ecology of largemouth bass in Parker Canyon Lake

Saiki, Michael K. (Michael Kenichi), 1949- January 1973 (has links)
No description available.
133

Caracteriza??o e an?lise do talude continental adjacente ? bacia potiguar, NE Brasil

Almeida, Narelle Maia de 21 February 2014 (has links)
Made available in DSpace on 2015-03-13T17:08:39Z (GMT). No. of bitstreams: 1 NarelleMA_DISSERT.pdf: 7040966 bytes, checksum: 66462f8e5d4ada5ffd979bea8a0e35a9 (MD5) Previous issue date: 2014-02-21 / This work presents the results of the first imaging of continental slope adjacent to Potiguar Basin, in the equatorial Brazilian margin (NE Brazil). Swath bathymetry provided a complete coverage of seafloor between the upper and middle slope (100-1,300 m). Fifteen submarine canyons were mapped. The shape of the slope reflects in distinct spatial distribution of the canyons. The western area displays convex profiles which implied a greater amount of incisions by canyons. Some of them have gradient walls higher than 35?. They were classified according to location and morphology. The canyons with heads indenting shelf edge, association with a incised valley and a large fluvial system, high sinuosities, V shape, terraces along margins, further erosive features such as landslide and gullies allow to deduce a sandy-gravelly sedimentation. These canyons are associated with deposition of submarine fan systems that have been considered permeable hydrocarbon reservoirs. The presence of gullies, furrows and dunes demonstrates the role of bottom currents in the shaping of the slope. The enlargement of canyons and the change in the course when they cross the border fault imply that tectonic has also influenced in the morphology of deep waters environments of Potiguar Basin. The current sedimentation of continental slope is considered mixed because the sediments are composed of siliciclastics and bioclasts. Predominant siliciclastics are calcite, dolomite, quartz, and clay minerals. The presence of stable minerals (zircon, tourmaline and rutile), and fragmented bioclasts implies the contributions of Rivers A?u and Apodi / Esta disserta??o apresenta os resultados do primeiro imageamento realizado no talude continental, em ?rea adjacente ? Bacia Potiguar, na margem equatorial brasileira (NE Brasil). Dados de batimetria multifeixe forneceram uma cobertura completa do fundo oce?nico entre o talude superior e o talude intermedi?rio (100-1300 m). Quinze canyons submarinos foram mapeados. A forma do talude reflete na distinta distribui??o espacial dos canyons. A parte oeste apresenta perfis convexos o que implicou numa maior quantidade de incis?es pelos canyons. Alguns deles possuem paredes com declividades maiores que 35?. Os canyons foram classificados de acordo com sua localiza??o e morfologia. Os canyons com cabeceiras entalhadas na plataforma, conex?o com sistemas fluviais, altas sinuosidades, formas em V , terra?os ao longo das margens e com fei??es erosivas como ravinas permitem deduzir uma sedimenta??o areno-cascalhosa. Estes canyons s?o associados ? deposi??o de sistemas de leques submarinos que t?m sido considerados reservat?rios de hidrocarbonetos. A presen?a de ravinas, ranhuras e dunas demonstram o papel das correntes de fundo na forma do talude. Os alargamentos dos canyons e a mudan?a na dire??o do curso onde cruzam a falha de borda da bacia implicam que a tect?nica tamb?m influencia na morfologia dos ambientes profundos da Bacia Potiguar. A sedimenta??o atual do talude continental ? considerada mista, pois os sedimentos possuem componentes silicicl?sticos e biocl?sticos. Dentre os silicicl?sticos destacam-se calcita, dolomita, quartzo e os argilominerais. A presen?a de alguns minerais pesados tais como zirc?o, turmalina e rutilo, bem como biocl?sticos fragmentados, indicam a maturidade dos sedimentos e a contribui??o dos Rios A?u e Apodi para os sedimentos da ?rea de estudo
134

Modélisation dynamique multi-échelle de la pollution atmosphérique en milieu urbain / Multiscale dynamic modeling of atmospheric pollution in urban environment

Thouron, Laëtitia 30 May 2017 (has links)
La pollution atmosphérique en milieu urbain a été identifiée comme une cause importante d’impacts sanitaires, y compris de décès prématurés. En particulier, les concentrations ambiantes de polluants gazeux tels que le dioxyde d’azote (NO2) et de particules (PM10 et PM2,5) sont réglementées, ce qui implique que des stratégies de réductions d’émissions doivent être mises en place pour diminuer ces concentrations dans les lieux où la réglementation correspondante n’est pas respectée. Par ailleurs, la pollution atmosphérique peut contribuer à la contamination d’autres milieux, par exemple à travers la contribution des dépôts atmosphériques à la contamination des eaux de ruissellement.Les aspects multifactoriels et multiéchelle de la pollution en ville rendent l’identification des sources difficile. En effet, le milieu urbain est un espace hétérogène caractérisé par des structures architecturales complexes (bâti ancien côtoyant un bâti plus moderne, zones résidentielles, commerciales, industrielles, axes routiers…), des émissions de polluants atmosphériques non uniformes et par conséquent une exposition de la population à la pollution qui est variable dans l’espace et le temps.La modélisation de la pollution atmosphérique urbaine a pour vocation de comprendre l’origine des polluants, leur étendue spatiale et leur niveau de concentrations/dépôt. Certains polluants ont des temps de résidence long et peuvent séjourner plusieurs semaines dans l’atmosphère (PM2,5) et donc être transportés sur de longues distances, d’autres au contraire, sont plus locaux (NOx en proximité du trafic). La répartition spatiale d’un polluant dépendra alors de plusieurs facteurs et notamment des surfaces rencontrées. La qualité de l’air, elle, dépend fortement des conditions météorologiques, du bâti (rue-canyon) et des émissions.L’objectif de cette thèse est de traiter certains de ces aspects en modélisant : (1) la pollution urbaine de fond avec un modèle de chimie-transport (Polyphemus/POLAIR3D), qui permet d’estimer les dépôts de polluants atmosphériques par type de surfaces urbaines (toits, murs et chaussées), (2) la pollution à l’échelle de la rue en intégrant explicitement les effets du bâti de manière tridimensionnelle avec d’une part un modèle multiéchelle de chimie-transport (SinG) et d’autre part un modèle de mécanique des fluides (Code_Saturne) et (3) un processus de micro-échelle qui est la réémission des particules présentes sur la chaussée par le trafic routier avec trois formulations différentes (déterministe, semi-empirique et empirique). L’intérêt de cette thèse est de pouvoir comparer et évaluer l’opérabilité et la performance de plusieurs modèles de qualité de l’air à plusieurs échelles (région, quartier et rue) afin de mieux appréhender la caractérisation de la qualité de l’air en milieu urbain / Urban air pollution has been identified as an important cause of health impacts, including premature deaths. In particular, ambient concentrations of gaseous pollutants such as nitrogen dioxide (NO2) and particulate matter (PM10 and PM2.5) are regulated, which means that emission reduction strategies must be put in place to reduce these concentrations in places where the corresponding regulations are not respected. Besides, air pollution can contribute to the contamination of other media, for example through the contribution of atmospheric deposition to runoff contamination.The multifactorial and multiscale aspects of urban make the pollution sources difficult to identify. Indeed, the urban environment is a heterogeneous space characterized by complex architectural structures (old buildings alongside a more modern building, residential, commercial, industrial zones, roads, etc.), non-uniform atmospheric pollutant emissions and therefore the population exposure to pollution is variable in space and time.The modeling of urban air pollution aims to understand the origin of pollutants, their spatial extent and their concentration/deposition levels. Some pollutants have long residence times and can stay several weeks in the atmosphere (PM2.5) and therefore be transported over long distances, while others are more local (NOx in the vicinity of traffic). The spatial distribution of a pollutant will therefore depend on several factors, and in particular on the surfaces encountered. Air quality depends strongly on weather, buildings (canyon-street) and emissions.The aim of this thesis is to address some of these aspects by modeling: (1) urban background pollution with a transport-chemical model (Polyphemus / POLAIR3D), which makes it possible to estimate atmospheric pollutants by type of urban surfaces (roofs, walls and roadways), (2) street-level pollution by explicitly integrating the effects of the building in a three-dimensional way with a multi-scale model of transport chemistry (SinG) and (3) a microscale process which is the traffic-related resuspension of the particles present on the road surface with three different formulations (deterministic, semi-empirical and empirical).The interest of this thesis is to compare and evaluate the operability and performance of several air quality models at different scales (region, neighborhood and street) in order to better understand the characterization of air quality in an urban environment
135

An Analysis of the Rhetoric of Agitation and Control in the Sierra Club Campaign to Protect the Grand Canyon

Wilson, Joy 12 1900 (has links)
This study of the rhetoric in the Sierra Club's Grand Canyon Campaign, 1963 to 1967 seeks to determine the decisive strategies in the success of the campaign. Criteria for examining the rhetoric are adapted from the fields of rhetoric and sociology. This analysis examines preconditions of this conservation campaign, its leaders, membership, strategies, and audience-speaker relationships, The campaign's turning point came when the club used public audiences to pressure Control into capitulating to Agitation's demands, Other factors in the campaign's success were the Sierra Club's purity of belief, suppression action by Control, and incomplete purity of belief in the leader of Control.
136

Resource utilisation of the Chacma baboon in different vegetation types in North-Eastern Mountain Sour Veld, Blyde Canyon Nature Reserve

Marais, A. J. (Albertus Johannes) 31 May 2005 (has links)
The Blyde Canyon Nature reserve displays its natural beauty for most National and International visitors all over the World. The region is renowned for its high rainfall and misty weather, which enhances the natural beauty of the area. Because of the mist belt effect, the area is one of the largest commercial forestry areas in South Africa. Baboons also seek after the topography and vegetation type (Northeastern mountain sourveld) that is typical of this area and numerous baboon troops occur in this region. This combination is often the cause of conflict between baboons and humans. The need arise for these baboons to be studied and managed as a component of this very important ecosystem. The main aims of the study were firstly to identify a natural ranging baboon troop, to habituate them and gather data regarding home range sizes, troop sizes, densities and seasonal food selection and secondly to give a detailed habitat description and vegetation map of the troop's home range. The baboon activity data was collected in 15-minute intervals over a one year period on a troop at Bourke's Luck. This included all activities such as walking, social, foraging, and resting. The food parts selected as well as the species foraged on was identified. Numerous statistical methods were used on the baboon data such as; the Shapiro Wilk test, Spearman rank-order correlation, ANOVA, and the Kolmogarov-Smirnov two sample test. There was a positive correlation between home range areas and troop sizes and the baboons preferred certain habitats above others during different seasons. To give a detailed habitat description of the troop's home range, 50 sample plots was stratified-randomly distributed in order to include all the different stratification units. a TWINSPAN classification, refined by Braun-Blanquet procedures was carried out on the Bourke's Luck section that included the baboons home range. 13 Plant communities, which can be grouped into 7 major community types were identified. This study resulted in the ecological interpretation of baboon activities related to the ecological interpretation of the vegetation in the baboon troop's home range. / Agriculture, Animal Health and Human Ecology / M.Tech. (Nature Conservation)
137

The ethnobotany and phenology of plants in and adjacent to two riparian habitats in southeastern Arizona.

Adams, Karen Rogers. January 1988 (has links)
Two riparian habitats in southeastern Arizona provide the setting for a study of 127 plants useful to human foragers. A view of plant part availability is based on annual phenological profiles, and on historic and prehistoric records of plant use. Food choice is limited in March and April, but high August through November. Riparian plants also offer numerous non-food resources. Trees and shrubs serve more needs in relation to number of available species than do perennial herbs (including grasses) and annuals. Southwestern ethnographic literature hints that certain native taxa (Panicum, Physalis, Populus, Salix, Typha and Vitis) might receive special care. Inherent qualities of parts, coupled with ethnographic records of preparation and use, provide a basis for speculation on which parts might survive in an ancient record. Most are expected to disintegrate in open sites. Parts sought for different needs can enter a dwelling via diverse routes that produce confusingly similar archaeological debris. Modern experiments to wash pollen from 14 separate harvests permit evaluation of plant fruit and leaves as pollen traps, to help interpret pollen recovered from ancient dwellings. High amounts of Berberis, Rumex and Ribes pollen, sometimes in clumps or as tetrads, travel on harvested fruit. Arctostaphylos, Monarda, Oxalis, Rhus, Rhamnus, Vitis and Juniperus parts carry lower amounts. Quercus and Gramineae pollen grains travel on parts of other taxa, as well as on their own fruit. The phenological profiles offer insight into group life-form activities in response to local temperature and precipitation trends. Rising and maximum temperatures coincide with intense vegetative and reproductive activity for trees, shrubs, herbaceous perennials, and annuals. Increased levels of precipitation coincide with maximum flowering and fruiting of herbaceous perennials and fall annuals. Limited data on six taxa from Utah generally agrees with observations in this study, suggesting strong genetic control in the phenology of some riparian taxa.
138

Resource utilisation of the Chacma baboon in different vegetation types in North-Eastern Mountain Sour Veld, Blyde Canyon Nature Reserve

Marais, A. J. (Albertus Johannes) 31 May 2005 (has links)
The Blyde Canyon Nature reserve displays its natural beauty for most National and International visitors all over the World. The region is renowned for its high rainfall and misty weather, which enhances the natural beauty of the area. Because of the mist belt effect, the area is one of the largest commercial forestry areas in South Africa. Baboons also seek after the topography and vegetation type (Northeastern mountain sourveld) that is typical of this area and numerous baboon troops occur in this region. This combination is often the cause of conflict between baboons and humans. The need arise for these baboons to be studied and managed as a component of this very important ecosystem. The main aims of the study were firstly to identify a natural ranging baboon troop, to habituate them and gather data regarding home range sizes, troop sizes, densities and seasonal food selection and secondly to give a detailed habitat description and vegetation map of the troop's home range. The baboon activity data was collected in 15-minute intervals over a one year period on a troop at Bourke's Luck. This included all activities such as walking, social, foraging, and resting. The food parts selected as well as the species foraged on was identified. Numerous statistical methods were used on the baboon data such as; the Shapiro Wilk test, Spearman rank-order correlation, ANOVA, and the Kolmogarov-Smirnov two sample test. There was a positive correlation between home range areas and troop sizes and the baboons preferred certain habitats above others during different seasons. To give a detailed habitat description of the troop's home range, 50 sample plots was stratified-randomly distributed in order to include all the different stratification units. a TWINSPAN classification, refined by Braun-Blanquet procedures was carried out on the Bourke's Luck section that included the baboons home range. 13 Plant communities, which can be grouped into 7 major community types were identified. This study resulted in the ecological interpretation of baboon activities related to the ecological interpretation of the vegetation in the baboon troop's home range. / Agriculture, Animal Health and Human Ecology / M.Tech. (Nature Conservation)
139

Using Travertine-Cemented Fault Breccias to Understand the Architecture and History of the Gunnison Fault Zone, eastern Basin and Range, Utah

Main, Joel 30 December 2015 (has links)
No description available.
140

The petrology and geochemistry of the Cienega Falls diabase sill, Salt River Canyon area, Gila County, Arizona

Schofield, Richard Edward, 1946- January 1976 (has links)
No description available.

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