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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.
51

ROTEIRO GEOLÓGICO NOS MUNICÍPIOS DE CASTRO E TIBAGI, PR – BRASIL.

Matsumura, Willian Mikio Kurita 19 April 2010 (has links)
Made available in DSpace on 2017-07-21T18:13:42Z (GMT). No. of bitstreams: 1 Introducao.pdf: 3135387 bytes, checksum: 9e349e21896905091b64a491c6e94325 (MD5) Previous issue date: 2010-04-19 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / The Campos Gerais region, Paraná, Brazil, holds unique geological, geomorphological e paleontological sets, which are target of numerous works and scientific researcher. This research present a geological and paleontological route using the outcrops occurring along existing roads in the municipalities of Castro and Tibagi, Parana State, Brazil. This roadmap is proposed as a tool to aid teaching and scientific support for fieldworks (classes or applied basic research) developed by teachers and researchers. Fieldwork carried out aimed to the regional recognition and description of stratigraphic sections of the surface, according to the geological context of the Castro and Paraná basins. For each outcrop were built columnar sections showing the following items: 1) lithological description, 2) sedimentary structures and 3) fossil content occurring. All outcrops were correlated with stratigraphic frameworks pre-existing. A total of 20 raised and described outcrops then organized in the form of stopping points along the road PR- 151, PR-340, BR-153 and secondary roads. Stratigraphically the roadmap begins in the volcanic and volcaniclastic rocks Ordovician of Castro Basin. Then cover the glacial rocks of Neo-Ordovician from Iapó Formation and the fluvial-marine rocks Siluro- Devonian from Formation Furnas, and pelitic rocks of the Devonian from Ponta Grossa Formation, ending with the glaciogenic rocks Neo-Carboniferous from Itararé Group (belonging to the Paraná Basin). This roadmap allows the monitoring of succession lithological, stratigraphic, sedimentological and paleobiological in the interval Lower Ordovician and Upper Carboniferous in the Campos Gerais region of Paraná, facilitating public access to new target areas of outcrops and providing a history of research and discoveries each point.. / A região fisiográfica dos Campos Gerais do Paraná é detentora de um conjunto singular de feições geológicas, geomorfológicas e paleontológicas que são alvos de inúmeros trabalhos e pesquisas científicas. Apresenta-se aqui um roteiro geológico e paleontológico utilizando-se de afloramentos rochosos ocorrentes ao longo de rodovias existentes nos municípios de Castro e Tibagi, Estado do Paraná, Brasil. Este roteiro é proposto como um instrumento de auxílio didático e apoio científico para atividades práticas de campo (aulas ou pesquisa básica aplicada) desenvolvidas por professores e pesquisadores. Trabalhos de campo realizados objetivaram o reconhecimento regional e a descrição das seções estratigráficas de superfície, segundo o contexto geológico das bacias de Castro e do Paraná. Para cada afloramento foram construídas seções colunares apresentando os seguintes ítens: 1) descrição litológica, 2) estruturas sedimentares e 3) conteúdo fossilífero ocorrente. Todos os afloramentos foram correlacionados a arcabouços estratigráficos pré-existentes. No total foram levantados e descritos 20 afloramentos rochosos organizados então sob a forma de pontos de parada ao longo das rodovias PR-151, PR-340, BR-153 e estradas secundárias. Estratigraficamente inicia-se nas rochas vulcânicas e vulcanoclásticas ordovicianas da Bacia de Castro. Em seguida abrange as rochas glaciais neo-ordovicianas da Formação Iapó e as rochas flúviomarinhas siluro-devonianas da Formação Furnas e pelíticas devonianas da Formação Ponta Grossa, encerrando com as rochas glaciogênicas neo-carboníderas do Grupo Itararé (pertencentes à Bacia do Paraná). O presente roteiro permite o acompanhamento das sucessões litológicas, estratigráficas, sedimentológicas e paleobiológicas no intervalo Ordoviciano Inferior e o Carbonífero Superior na região dos Campos Gerais do Paraná, facilitando o acesso do público alvo a novas regiões de afloramentos e fornecendo um histórico das pesquisas e descobertas de cada ponto.
52

Chondrichthyan Diversity within the Burlington-Keokuk Fish Bed of Southeast Iowa and Northwest Illinois (Mississippian: Osagean)

Hoenig, Matthew Michael James 17 December 2019 (has links)
No description available.
53

87Sr/86Sr Isotope Composition of Bottled British Mineral Waters for Environmental and Forensic Purposes

Montgomery, Janet, Evans, J.A., Wildman, G. January 2006 (has links)
No / Mineral waters in Britain show a wide range of 87Sr/86Sr isotope compositions ranging between 87Sr/86Sr = 0.7059 from Carboniferous volcanic rock sources in Dunbartonshire, Scotland to 87Sr/86Sr = 0.7207 in the Dalradian aquifer of Aberdeenshire, Scotland. The 87Sr/86Sr composition of the waters shows a general correlation with the aquifer rocks, resulting in the waters from older rocks having a more radiogenic signature than those from younger rocks. This wide range of values means that the Sr isotope composition of mineral water has applications in a number of types of studies. In the modern commercial context, it provides a way of fingerprinting the various mineral waters and hence provides a method for recognising and reducing fraud. From an environmental perspective, it provides the first spatial distribution of bio-available 87Sr/86Sr in Britain that can be used in modern, historical and archaeological studies
54

The Conodont Biostratigraphy of the Black Prince Limestone (Pennsylvanian) of Southeastern Arizona

Barrie, Kathleen Ann January 1975 (has links)
The Black Prince Limestone of southeastern Arizona has been assigned to the Morrowan on the basis of several long-ranging fossils. Since these were not especially diagnostic, the exact time represented by the Black Prince within the Morrowan was uncertain. To date the Black Prince more precisely, six sections were systematically sampled for conodonts. The condonts found, especially Neognathodus bassleri, Rachistognathus muricatus, Idiognathoides convexus, and Spathoqnathodus coloradoensis, indicate a middle Morrowan to early Derryan age for the Black Prince in the study area. Four conodont zones can be recognized: the Neognathodus bassleri Zone, the Idiognathodus sinuosis.- Streptognathodus anteeccentricus Zone , the Idiognathoides convexus Zone, and the Spathognathodus coloradoensis-Neognathodus columbiensis Zone. These zones compare favorably with the zonation previously established in the type Morrowan. This biostratigraphic evidence suggests that the hiatus between the Black Prince and Horquilla Limestones increases in magnitude from southeastern to south-central Arizona. The Black Prince represents a sequence of tidal flat and shallow subtidal carbonate deposits. Mudstones and sparsely fossiliferous wackestones with low fossil diversity and abundance characterize the tidal-flat facies. Grainstones, packstones, and fossiliferous wackestones with high fossil diversity and abundance characterize the shallow subtidal facies.
55

A Stratigraphic Analysis of Rico Strata in the Four Corners Region

Bailey, James S. January 1955 (has links)
Rico strata are recognised throughout the Four Corners region of southwestern Colorado, southeastern Utah, northeastern Arizona, and northwestern New Mexico. The term Rico has been applied to a group of strata which exhibit a lateral and vertical transition between two contrasting environments, the marine Hermosa and the non-marine Cutler. Two faunal provinces reflect these widely diverse conditions of sedimentation. However, few fossils of diagnostic value have been discovered despite the abundance of fossiliferous strata within the Rico. Rico strata are believed to range between Desmoinesian and Virgilian in age. Lithofacies data on the Rico were assembled from literature, outcrop sections, and various well logs. These data were then compiled on an isopach-lithofacies map. The isopach-lithofacies map shows the thickness trends and the lithologic variations of Rico strata throughout the region of study. The tectonic framework of the region is reconstructed from the isopach-lithofacies map and mechanical analyses of the elastic strata. Clastic material in the Rico increases in average grain size from west to east toward the Uncomphagre Uplift suggest that this area was actively positive during Rico time. The vertical variation of normal marine limestone and clastic red beds in the Rico reflect an alternately transgressing and regressing sea over much of the Four Corners region. This intricate intertonguing of normal marine limestone and clastic red beds probably resulted from deposition in a shallow basin on an unstable shelf. The occurrence of oil, gas, and cement quality limestone in the Rico is examined from an economic aspect. A. brief review of the general geology and geologic history of tile region is also included.
56

Hydrogéologie d'un aquifère karstique des calcaires carbonifères (Néblon-Anthisnes, Belgique): Apport des traçages à la connaissance des milieux fissurés et karstifiés.

Meus, Philippe 30 April 1993 (has links)
Cette thèse est avant tout consacrée à létude des circulations karstiques dans les calcaires carbonifères du Sud de la Belgique. Son objectif est double : dune part, approfondir la connaissance de laquifère à partir de létude dune région limitée située dans le Condroz à lextrémité Est du synclinorium de Dinant (bassins dAnthisnes et du Néblon), dautre part mettre au point des méthodes de mise en uvre et dinterprétation des traçages permettant de caractériser le comportement de laquifère lié à sa « double perméabilité ». Dans ce but, plusieurs aquifères fissurés ou karstiques sont comparés. Lintroduction générale présente une synthèse des conceptions actuellement utilisées en hydrogéologie karstique et définit le calcaire carbonifère en tant quaquifère (intérêt économique, particularités du fonctionnement) dans le contexte plus général des aquifères carbonatés du sud de la Belgique. La première partie est consacrée à létude de la structure (approche structurelle) et du fonctionnement (approche systémique) de deux systèmes karstiques drainant la même nappe dans les calcaires du Tournaisien et du Viséen : le bassin dAnthisnes, dont lexutoire est la résurgence de Comblain-au-Pont, et le bassin du Néblon drainé par les sources du Néblon. Les structures de ces deux systèmes sont comparées à laide de diverses méthodes géophysiques (électriques, électromagnétiques, diagraphiques) et à partir des observations en surface (fissuration, linéaments). Les différences de comportement sont liées au développement de la karstification. Elles apparaissent de manière très nette en considérant les réponses naturelles (hydrodynamique, hydrogéochimie) et provoquées (traçages). Dans la seconde partie, une série de tests en écoulement naturel et en écoulement radial convergent permettent détudier les propriétés de transport des traceurs au sein de différents aquifères fissurés et karstiques et de dégager des tendances liées à la structure du milieu. Trois types daquifère sont envisagés : les calcaires dévoniens et carbonifères (aquifère principalement à porosité dinterstice). Un examen critique des lois découlement et de transport utilisées, ainsi que des différents types de traçage et types de traceur, est effectué au préalable. Plusieurs solutions analytiques sont envisagées pour déterminer les paramètres hydrodispersifs des aquifères. Les dispersivités longitudinales des calcaires sont comprises entre 10 et 100m ; celles des craies entre 2 et 14m et celles des tuffeaux entre 2 et 5m. ABSTRACT. The actual scope of this research is to study the karstic groundwaters in the carboniferous limestones south of Belgium. The study deals with two different approaches, one in a local framework, the other thematic. On the one hand, two karstic systems are described in the synclinorium of Dinant in the Condroz region (Anthisnes and Neblon basins). On the other hand, a methodology of tracer tests, and their interpretation as well, are developed in order to understand groundwater flows related to the dual permeability of the aquifer. As a comparison, the tracer study is enlarged to other karstic and fissured aquifers. The introduction deals with some general features about karst hydrogeology. The carboniferous limestones and their economic interest are presented in the regional framework of all the carbonated rocks in south Belgium. The two karstic systems described in the first part belong to the same water table in the Tournaisian and Visean beds. Their structure is studied by mean of geophysical prospecting (electric, electromagnetic, well logging) and fissuration measurements. The mechanisms of groundwater circulations are then studied by using undirect investigations such as hydrodynamical, hydrogeochemical or tracing investigations. These methods are applied to the main springs of each system: the spring of Comblain-au-Pont (Anthisnes basin) and the springs of the Neblon (Neblon basin). The behaviour of each system is related to its stage of karstification. The second part deals with tracer tests in natural and radially convergent flow pattern. The aim is to distinguish among the features of the tracer curves those due particularly to the structure of the fissured network of the aquifer. Three different kinds of aquifer are studied: the Devonian and carboniferous limestones (both fissured and karstic), the cretaceous chalks (mainly fissured), and the landenian tuffaceous sands (mainly porous). After describing the theory of groundwater flow and transport in fissured media, we justify the use of different tracers and tracing methods. Afterwards different mathematical models are used to calibrate the dispersion parameters. The longitudinal dispersivities are ranging between 10 and 100m in the limestones, between 2 and 14m in the chalk and between 2 and 5m in the landenian sands.
57

Oceanic and atmospheric response to climate change over varying geologic timescales

Woodard, Stella C. 2011 May 1900 (has links)
Global climate is controlled by two factors, the amount of heat energy received from the sun (solar insolation) and the way that heat is distributed Earth's surface. Solar insolation varies on timescales of 10s to 100s of thousands of years due to changes in the path of Earth's orbit about the sun (Milankovitch cycles). Earth's internal boundary conditions, such as paleogeography, the presence/absence of polar icecaps, atmospheric/oceanic chemistry and sea level, provide distribution and feedback mechanisms for the incoming heat. Variations in these internal boundary conditions may happen abruptly or, as in the case of plate tectonics, take millions of years. We use geochemical and sedimentological techniques to investigate the response of ocean chemistry, regional aridity and atmospheric and oceanic circulation patterns to climate change during both greenhouse and icehouse climates. To explore the connection between orbitally-forced changes in solar insolation, continental aridity and wind, we generated a high-resolution dust record for ~58 Myr old deep-sea sediments from Shatsky Rise. Our data provide the first evidence of a correlation between dust flux to the deep sea and orbital cycles during the Early Paleogene, indicating dust supply (regional aridity) responded to orbital forcing during the last major interval of greenhouse climate. The change in dust flux was comparable to that during icehouse climates implying subtle variations in solar insolation have a similar impact on climate during intervals of over-all warmth as they do during glacial-interglacial states. The Carboniferous Period (359-299 Ma) marks a critical time in Earth's history when a series of tectonic and biological events caused a shift in the mean climate state from a global "greenhouse" to an "icehouse". Geochemical records extracted from sedimentary rocks deposited in shallow epicontinental seaways are increasingly being used to infer relationships between tectonism, carbon cycling and climate and therefore are assumed to reflect global ocean processes. We analyzed radiogenic isotopes in biogenic apatite along a North American transect to constrain the degree of geochemical coupling between the epicontinental seas and the open ocean. Our results argue strongly for decoupling of North American seaways from the open ocean by latest Mississippian time.
58

Sequence Stratigraphy of the Bridal Veil Falls Limestone, Carboniferous, Lower Oquirrh Group, on Cascade Mountain, Utah: A standard Morrowan Cyclostratigraphy for the Oquirrh Basin

Shoore, David Joseph 21 March 2005 (has links) (PDF)
The Bridal Veil Falls Limestone (lowest 400 meters of the Permo-Carboniferous Oquirrh Group) is well exposed on the flanks of Cascade Mountain (Wasatch Front and adjacent mountain ranges) near Provo, Utah. Because of its excellent exposure and location in the heart of the Oquirrh depocenter, this area was selected to develop a sequence stratigraphic framework for Morrowan rocks that may be applied throughout the Oquirrh basin (NW Utah and southern Idaho) as well as the adjacent Ely and Bird Springs troughs. Eleven partial to complete sections of the Bridal Veil Falls Limestone were measured along the west and north flanks of Cascade Mountain and the south end of Mt. Timpanogos. There the limestone is comprised principally of mud-rich carbonate lithofacies punctuated by thin, and sometimes discontinuous quartzose sandstone beds. The predominance of muddy to grain-rich heterozoan limestone microfacies suggests deposition on a west-dipping low energy carbonate ramp that prograded westward throughout Morrowan time. Sandstones reflect transport of siliciclastics from the incipient Weber shelf (located to the NE) during episodes of sea-level lowstand. The Bridal Veil Falls Limestone is subdivided into 21, third and fourth order depositional sequences ranging in thickness from 3 to 60 meters, and 62 parasequences. Parasequences are commonly asymmetrical, reflecting rapid flooding followed by protracted shoaling and/or sea level drop. Selected cycles are recognized in the Lake Mountains, Thorpe Hills, and the southern Oquirrh Mountains to the west of Cascade Mountain indicating that Parasequences delineated at Cascade Mountain are regionally extensive over an area of at least 300 square kilometers.
59

DEVELOPMENT OF A RATING CLASSIFICATION FOR ROCK TO BE USED AS TOE-BENCH MATERIAL

Griffin, Jason Allan 07 July 2008 (has links)
No description available.
60

Ablagerungsfazies der Grobklastika der oberen Halle-Formation

Grieswald, Heike 21 June 2016 (has links) (PDF)
Die Sedimente des Halleschen Permokarbonkomplexes gaben schon immer Raum für Spekulationen. Aufgrund ihrer Dominanz an rhyolithischen Geröllen wurden sie über einen langen Zeitraum einheitlich als Postporphyrschutt ausgehalten. Vielfältig wechselnde Faziesbedingungen machten es jedoch notwendig, die Sedimente aufzugliedern. Neuere Erkenntnisse in der Erforschung des Halleschen Permokarbonkomplexes erfordern eine Überprüfung v. a. der nach KUNERT (1995) aufgestellten allgemeinen stratigraphischen Gliederung der Unterrotliegendsedimente in Halle,- Hornburg,- Sennewitz- und Brachwitz-Formation anhand einiger ausgewählter Beispiele. Der ursprüngliche Gedanke der Diplomarbeit bestand darin, eine Fazies- und eine Geröllanalyse der unterpermischen Abtragungsprodukte des Halle-Vulkanitkomplexes anzufertigen. Zur Verfügung standen zwei Kernbohrungen und zwei Aufschlüsse, sowie diverse Unterlagen zu angrenzenden Bohrungen in der Saale-Senke. Die beiden Oberflächenaufschlüsse Riveufer und Teichgrund sollten stratigraphisch aufgenommen werden, so dass eine Fazieszuordnung möglich ist. Die Bohrung Brachwitz 2/62 wurde mit dem Ziel aufgenommen, neuere Theorien über den Ablagerungszeitraum der Rotliegend-Sedimente in Bezug auf den permokarbonen Vulkanismus zu widerlegen oder zu bekräftigen. Die zweite Bohrung (Kb Lochau 7/65) wurde am Rande mit in die Diplomarbeit einbezogen, da sie das immense Spektrum der spätvulkanischen Aktivitäten im Halle Permokarbonkomplex erweitert. Ergebnis ist eine Neugliederung des Rotliegend im Halleschen Permokarbonkomplex, in der nur noch die Halle-Formation mit ihrem ausgeprägten Vulkanismus und die Hornburg-Formation, stellvertretend für alle jüngeren Abtragungsprodukte des Halle Vulkanitkomplexes, unterschieden werden. Mit einem großen Hiatus folgt anschließend die Eisleben-Formation.

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