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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.
121

A microscopic study of an early Pennsylvanian flora from the Manning Canyon shale, Utah

Blaylock, Max W. 01 August 1965 (has links)
The Manning Canyon Shale on the eastern slope of Lake Mountain in Utah County, Utah contains an Early Pennsylvanian flora within its upper shales. Many of these fossils appear to be new species. A microscopic study of the tissue remains can be of value in the further classification of these fossils. Selected fossils were macerated in hydrofluoric acid, and the residues were examined microscopically for tissue remains. Objects identified as fossil tissue remains were found in twenty five of the forty-eight specimens examined. Fibers, fiber tracheids, tracheids, and spores were isolated from fossils identified as Calamites. The spores were possibly recent fungus spores from the laboratory. Most of the fossils identified as Cordaites had little or no remaining organic material, but one fiber and a peel showing the outlines of cells which were presumed to be epidermal cells were found. A fiber and a fiber tracheid were isolated from a Lepidostrobus. A spore was found in the maceration residue of a fossil identified as Lepidodendron but was too decomposed to be classified as to the type of spore. Many of the fossils collected from the Manning Canyon Shale appear to be portions of stems, roots, or rachises of undetermined affinities. These were lumped together for this study under the classification of "stems." Xylem elements, cuticles, sclereids, and an
122

The algae of Huntington Canyon, Utah

Endsley, Carol Jean 01 August 1974 (has links)
A taxonomic study of the algae of Huntington canyon, Emery County, Utah, was conducted from March 1971 to April 1972. The algal flora of this cold, fast-flowing, hard-water mountain creek consisted of ninety-five genera, one hundred ninety-six species, twenty-nine varieties, and two forms. This diverse flora was dominated by many different species with usually rather few individuals of Achnanthes, Cymbella, Diatoma, Gomphonema, Lyngbya, Navicula, Nitzschia, Oscillatoria, Synedra, and Ulothrix.
123

A Geotechnical Investigation of the October 2011 Cedar City Landslide, Utah

Tizzano, Ashley S. 24 April 2014 (has links)
No description available.
124

Salinity Rates and Agricultural Productivity at Robert's Great House, Chaco Canyon, New Mexico

Thress, Jessica 28 June 2016 (has links)
No description available.
125

Geology of a part of Long Ridge, Utah

Muessig, Siegfried Joseph January 1951 (has links)
No description available.
126

Bacterial Survey of Representative Wells of Canyon, Texas, with Special Emphasis on Sanitation

Barnes, Adele 05 1900 (has links)
The problem of this thesis consists of a bacterial analysis of twenty-five representative wells within a radius of thirty miles of Canyon, Texas. An attempt has been made to determine the possible presence of the typhoid organism in these wells.
127

Geology and ore potential of the Jupiter Canyon region, Baboquivari Mountains, Arizona

Seaman, Sheila June January 1983 (has links)
No description available.
128

The Power Politics of Hells Canyon

Alford, John Matthew 08 1900 (has links)
This study examines the controversy regarding Hells Canyon on the Snake River, North America's deepest gorge. Throughout the 1950s, federal and private electric power proponents wrangled over who would harness the canyon's potential for generating hydroelectricity. After a decade of debate, the privately-owned Idaho Power Company won the right to build three small dams in the canyon versus one large public power structure. The thesis concludes that private development of Hells Canyon led to incomplete resource development. Further, support of private development led to extensive Republican electoral losses in the Pacific Northwest during the 1950s.
129

Geologia e gênese dos depósitos de Zn-Pb de Shalipayco e Florida Canyon, centro-norte do Peru / Geology and genesis of the Zn-Pb deposits of Shalipayco and Florida Canyon, central-northern Peru

De Oliveira, Saulo Batista 28 February 2019 (has links)
As mineralizações Mississipi Valley-type (MVT) dos depósitos de Zn-Pb de Shalipayco no centro do Peru e de Florida Canyon no norte do Peru, separados por centenas de quilômetros e hospedados na mesma sequência de rochas carbonáticas e evaporíticas de mais de mil quilômetros de extensão motivaram diversos questionamentos que vieram a compor esta tese. As questões fundamentais em que se basearam esta pesquisa são quais as possíveis conexões genéticas entre esses depósitos e como elas se relacionam com a evolução da bacia de Pucará. Assim o estudo enfoca os processos pré-, pós- e formadores do minério ocorrentes em ambos os depósitos, a idade das mineralizações, os controles estruturais e litológicos destas mineralizações, e as implicações para descoberta de novos depósitos neste contexto geológico. Estudos petrográficos, paragenéticos e de caracterização mineralógica, apoiados por análises isotópicas de carbono, oxigênio e estrôncio nos carbonatos e de enxofre, rubídio-estrôncio e chumbo-chumbo nos sulfetos permitiram identificação de fontes do fluido, de enxofre e de metal para mineralizações, a caracterização dos processos de interação fluido?rocha, das condições físico-químicas e dos mecanismos de deposição dos minérios nos depósitos de Florida Canyon e Shalipayco. As mineralogias de minério compostas por esfalerita, galena e pirita são as mesmas nos dois depósitos ocorrendo hospedadas em rochas denominadas dolomito poroso ou brecha dolomítica evaporítica. Estas rochas formam estratos permeáveis e porosos bem definidos, interpretados como fácies de ambiente deposicional sabkha intercalados em calcários finos da sequência do Grupo Pucará de idade Triássico Inferior a Jurássico Superior. Estes estratos originalmente de evaporitos provavelmente se tornaram dolomitos de granulação grossa durante diagênese de soterramento. Estes processos modificaram drasticamente as rochas originais e geraram porosidade e permeabilidade que tornaram estas rochas excelentes hospedeiras de hidrocarbonetos e mineralizações sulfetadas de Zn e Pb. Poros preenchidos por betume foram posteriormente preenchidos por esfalerita e galena e finalmente selados por dolomita tardia. Isótopos de carbono, oxigênio e estrôncio e imagens de catodoluminescência suportam a distinção de carbonatos de diagênese precoce, de diagênese de soterramento e tardios associados aos sulfetos de Zn e Pb, tanto em Florida Canyon quanto em Shalipayco. Os isótopos de enxofre indicam mistura de fontes de enxofre reduzido (BSR, TSR e/ou degradação térmica de matéria orgânica) que teriam se acumulado nos estratos de dolomito poroso e de brecha evaporítica. A mineralização MVT é posterior à migração e acumulação de óleo, e ambas ocorrem nas mesmas rochas do Grupo Pucará. O reconhecimento de mesmas rochas hospedeiras, mesma mineralogia e em mesma paragênese, condicionada por mesmos controles estruturais nos depósitos de Shalipayco e Florida Canyon permitiu assumir mesmos processos atuantes na Bacia Pucará. Foi possível associar estes processos geradores de rocha, de estruturas, de fluidos mineralizantes e de migração destes fluidos aos principais eventos tectônicos descritos na literatura para evolução Andina peruana. A estrutura dômica de Florida Canyon provavelmente se formou por halocinese durante a orogênese Juruá (157-152 Ma); a migração de hidrocarbonetos deve ter ocorrido durante o evento Mochica (100-95 Ma); e as mineralizações MVT de Zn-Pb de Shalipayco e Florida Canyon provavelmente sincrônicas, devem ter ocorrido durante ou logo após a orogênese Peruvian (86-83 Ma). Em Florida Canyon a mineralização supergênica de Zn é dada por smithsonita, hemimorfita e goethita, tendo sido gerada predominantemente por substituição direta da mineralização hipogena. Por correlação com as mineralizações zincíferas supergênicas da Mina Grande e Cristal no mesmo distrito de Bongará, pode-se atribuir a idade do Mioceno superior à de Florida Canyon. / The Mississipi Valley-type (MVT) Zn-Pb deposits of Shalipayco in central Peru and Florida Canyon in northern Peru are separated by hundreds of kilometers and hosted in the same sequence of carbonate and evaporite-bearing rocks that span more than thousand kilometers in the Pucará basin motivated several questions that came to compose this thesis. Fundamental questions that underpin the research of this this study are what are the possible genetic connections between these deposits and how do they related to the evolution of the Pucará basin. This study focuses on the investigation of the pre-, post- and ore-forming processes that occurred in both deposits; the age of the ore forming events; the structural and lithological controls on mineralization; and the implications for the discovery of new deposits in the basin. Petrographic, paragenetic and mineralogical studies supported by isotopic analyzes of carbon, oxygen and strontium in carbonates and sulfur, rubidium-strontium and lead-lead in the sulfides allowed the identification of possible fluid, sulfur and metal sources for mineralization, characterization of the rock-fluid interaction processes, physicochemical conditions and ore deposition mechanisms in the Florida Canyon and Shalipayco deposits. The sphalerite, galena and pyrite mineral assemblages are the same in the two deposits and occurs in porous dolostone or evaporite dolomitic breccia. These rocks form well-defined porous and permeable strata interpreted as depositional sabkha facies intercalated with fine limestones of the Pucará Group sequence from the Lower Triassic to the Upper Jurassic. These former evaporite-bearing strata were probably altered to coarse-grain dolomite during burial diagenesis. These processes drastically modified the original rocks and generated porosity and permeability that made these rocks an excellent host for hydrocarbons and Zn and Pb mineralization. Pores filled with bitumen were later filled by sphalerite and galena and finally sealed by late dolomite. Carbon, oxygen and strontium isotopes and cathodoluminescence images support the distinction between carbonates from early diagenesis, burial diagenesis, and late Zn and Pb mineralization, both in Florida Canyon and in Shalipayco. The sulfur isotopes indicate a mixture of reduced sulfur sources (BSR, TSR and/or possibly thermal cracking of organic matter) that would have accumulated in the porous dolomite and evaporite breccia strata interpreted as sabkha facies. The MVT mineralization occurred after the migration and accumulation of oil, in the same Pucará Group host rocks. The recognition of same host rocks, mineralogy and paragenesis, and same structural controls in the Shalipayco and Florida Canyon deposits suggests that the same processes of diagenesis and mineralization occurred on a basin-scale. It is possible to associate these processes of rock diagenesis, development of structural features and the generation and migration of the mineralizing fluids to the main tectonic events of the Peruvian Andean evolution. The Florida Canyon dome probably involved halokinesis during the Juruá orogeny (157-152 Ma). The migration of hydrocarbons probably occurred during the Mochica event (100-95 Ma) and the Shalipayco and Florida Canyon Zn-Pb MVT mineralization probably occurred during or just after the Peruvian orogeny (86-83 Ma). The supergene Zn mineralization in Florida Canyon deposit consists of smithsonite, hemimorphite and goethite which formed by direct replacement of hypogene sulfide mineralization. Supergene zinc mineralization in the Mina Grande and Cristal deposits in the Bongará district, occurred during the late Miocene, which may have also account for the supergene ores at the Florida Canyon deposit.
130

Watershed Condition Assessment for Little River Canyon National Preserve, Alabama

Rinehart, Nathan DeMille 01 December 2008 (has links)
No description available.

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