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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

Sédimentologie de dépôts quaternaires graveleux dans le bassin versant de la Rivière Chicoutimi à Laterrière, Québec /

Duchesne, Mathieu, January 2001 (has links)
Mémoire (M.Sc.T.)--Université du Québec à Chicoutimi, 2001. / Document électronique également accessible en format PDF. CaQCU
52

Stratigraphy, provenance, and tectonic evolution of Mesozoic basins in the Blue Mountains Province, eastern Oregon and western Idaho /

LaMaskin, Todd Allen, January 2009 (has links)
Typescript. Includes vita and abstract. Includes bibliographical references (leaves 185-232). Also available in ProQuest, free to University of Oregon users.
53

The bench deposits at Berger Bluff Early Holocene-Late Pleistocene depositional and climatic history /

Brown, Kenneth M. January 1900 (has links)
Thesis (Ph. D.)--University of Texas at Austin, 2006. / Vita. Includes bibliographical references.
54

Paleoenvironmental reconstruction of an active margin coast from the Pleistocene to the present : examples from southwestern Oregon /

Punke, Michele Leigh. January 1900 (has links)
Thesis (Ph. D.)--Oregon State University, 2006. / Printout. Includes bibliographical references. Also available online.
55

Detrital-zircon geochronologic provenance analyses that test and expand the East Siberia-West Laurentia Rodinia reconstruction

MacLean, John Stuart. January 2007 (has links)
Thesis (Ph. D.)--University of Montana, 2007. / Title from title screen. Description based on contents viewed July 19, 2007. Includes bibliographical references (p. 115-132).
56

Μελέτη της περιοχής του ΒΔ τμήματος του Πατραϊκού κόλπου για πιθανή εύρεση στόχων σχετικά με την ναυμαχία του Lepanto

Σκληβανιώτης, Λέανδρος, Τριχιά, Ελισάβετ 21 December 2012 (has links)
Η παρούσα μελέτη έγινε για την εύρεση στόχων των ναυαγίων κατά την ναυμαχία του Lepanto στην περιοχή της Ναυπάκτου με χρήση ηχοβολιστή πλευρικής σάρωσης, τομογράφου υποδομής πυθμένα και ανάλυση των αποτελεσμάτων με χρήση GIS. H επιλογή αυτών των συστημάτων βασίστηκε σε παρόμοιες έρευνες που πραγματοποιήθηκαν σε περιοχές άλλων ναυαγίων. Στην συνέχεια θα παρατεθεί η κάθε μελέτη ξεχωριστά. / --
57

Caracterização paleogeográfica de costões rochosos da porção sul do município de Ubatuba - SP / Paleogeographical characterization of rocky shores of the southern portion of the municipality of Ubatuba, SP, Brazil

Renata Diniz Teles 06 September 2016 (has links)
como uma tarefa importante das ciências relacionadas aos ambientes litorâneos. É importante progredir com os estudos, por meio da revisão e reinterpretação dos dados já existentes e da proposição de dados adicionais que elucidem as divergências que permeiam o delineamento das curvas de variação do nível do mar na costa brasileira e melhorem o diagnostico dos paleoníveis. A importância desses pesquisas reside no fato de que as variações contribuíram diretamente na formação e evolução das áreas costeiras. O município de Ubatuba possui grande potencial para a ocorrência de indicadores biológicos e geomorfológicos de paleoníveis marinhos, ainda pouco estudados em todo o litoral paulista. Estudos prévios que encontraram paleoindicadores biológicos de variações holocênicas do NM em alguns costões rochosos de Ubatuba, são um bom exemplo desse potencial. No presente trabalho avaliou-se 3 costões no município citado, quanto a suas características geomorfológicas e geológicas, e suas potencialidades para a ocorrência de indicadores de variação do NM. Os resultados apresentados permitem concluir que esses costões apresentam características peculiares que permitem o desenvolvimento e preservação de registros de NM. Pode-se inferir que as bandas de ouriços pormenorizadas no presente estudo definem níveis marinhos pretéritos, bem como os níveis de plataformas de abrasão marinha inativas aqui caracterizados. Tanto as plataforma quanto a presença das bandas sugerem pelo menos três estabilizações de NM mais alto que o atual, o que corrobora a literatura. Para estabelecer correlações entre as áreas estudas e delas com outras áreas do município, serão necessários estudos futuros, que contemplem ainda a datação de amostras de restos biogênicos, para que se possa relacionar os dados espaciais aqui apresentados com referencias temporais. / Responding to issues related to marine paleolevels reiterated increasingly as an important task of the science related to coastal environments. It is important to make progress with the studies through the review and reinterpretation of existing data and additional data proposition elucidating the differences that permeate the design of the variation curves sea level on the Brazilian coast and improve the diagnosis of paleolevels. The importance of these studies lies in the fact that changes have contributed directly to the formation and evolution of coastal areas. The city of Ubatuba has great potential for the occurrence of biological and geomorphological indicators of marine paleolevels, still understudied throughout the São Paulo coast. Previous studies have found that biological paleoindicadores of Holocene variations of sea level in some rocky shores of Ubatuba, are a good examples of this potential. In the present study we evaluated three rocky shores in Ubatuba as its geomorphological and geological features, and its potential for the occurrence of NM variation indicators. The results allow us to conclude that these shores have peculiar characteristics that enable the development and preservation of NM records. It can be inferred that the hedgehogs bands detailed in this study define tenses sea levels as well as levels of inactive marine abrasion platforms here characterized. Both the platform and the presence of the bands suggest at least three higher NM stabilizations that the current, which corroborates the literature. To establish correlations between them and studied areas with other areas of the municipality will require further study, still contemplating the dating of samples of biogenic remains, so that you can relate to the spatial data presented herein with temporal references.
58

Interpretação paleogeográfica de sítios arqueológicos em solos arenosos: o caso do sítio MT1 na bacia do médio rio Tocantins (TO) / Paleogeographical interpretation of archaeological sites in sandy soils: the case of MT1 site in the basin of the middle Tocantins river (TO)

Lima, Fernanda Rodrigues de 20 November 2015 (has links)
Submitted by Cláudia Bueno (claudiamoura18@gmail.com) on 2016-06-29T21:12:38Z No. of bitstreams: 9 Dissertação - Fernanda Rodrigues de Lima - 2015.pdf: 17446648 bytes, checksum: df774616998cda536a5e95fd2076294a (MD5) 1. Figura 8 - MapaA3_geologia.jpg: 9062069 bytes, checksum: caedbd95df087913eb2f26ce951d0118 (MD5) 2. Figura 16 - MapaA3_unidades do relevo.jpg: 6711605 bytes, checksum: c27cc059c83d2d0ddf510731713a59f5 (MD5) 3. Figura 17 - Mapa A3_formas do relevo.jpg: 7807858 bytes, checksum: 3a0c448103fffc374c328468dc9501af (MD5) 4. Figura 18 - MapaA3_hipsometria.jpg: 7859669 bytes, checksum: 3130d732d2aa93fccd88d447343a76a1 (MD5) 5. Figua 19 - MapaA3_declividade.jpg: 10945508 bytes, checksum: 0a87633e9c47a0646edfc2fc8cfe4391 (MD5) 6. Figura 20 - MapaA3_solo.jpg: 7347123 bytes, checksum: 2b9738898a1b1bd54ff5be5a326f2fd0 (MD5) 7. Figura 22 - MapaA3_hidrografia.jpg: 10595357 bytes, checksum: 5729e737839aa0a332774eae0227f9a6 (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) / Approved for entry into archive by Luciana Ferreira (lucgeral@gmail.com) on 2016-06-30T12:08:32Z (GMT) No. of bitstreams: 9 Dissertação - Fernanda Rodrigues de Lima - 2015.pdf: 17446648 bytes, checksum: df774616998cda536a5e95fd2076294a (MD5) 1. Figura 8 - MapaA3_geologia.jpg: 9062069 bytes, checksum: caedbd95df087913eb2f26ce951d0118 (MD5) 2. Figura 16 - MapaA3_unidades do relevo.jpg: 6711605 bytes, checksum: c27cc059c83d2d0ddf510731713a59f5 (MD5) 3. Figura 17 - Mapa A3_formas do relevo.jpg: 7807858 bytes, checksum: 3a0c448103fffc374c328468dc9501af (MD5) 4. Figura 18 - MapaA3_hipsometria.jpg: 7859669 bytes, checksum: 3130d732d2aa93fccd88d447343a76a1 (MD5) 5. Figua 19 - MapaA3_declividade.jpg: 10945508 bytes, checksum: 0a87633e9c47a0646edfc2fc8cfe4391 (MD5) 6. Figura 20 - MapaA3_solo.jpg: 7347123 bytes, checksum: 2b9738898a1b1bd54ff5be5a326f2fd0 (MD5) 7. Figura 22 - MapaA3_hidrografia.jpg: 10595357 bytes, checksum: 5729e737839aa0a332774eae0227f9a6 (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) / Made available in DSpace on 2016-06-30T12:08:32Z (GMT). No. of bitstreams: 9 Dissertação - Fernanda Rodrigues de Lima - 2015.pdf: 17446648 bytes, checksum: df774616998cda536a5e95fd2076294a (MD5) 1. Figura 8 - MapaA3_geologia.jpg: 9062069 bytes, checksum: caedbd95df087913eb2f26ce951d0118 (MD5) 2. Figura 16 - MapaA3_unidades do relevo.jpg: 6711605 bytes, checksum: c27cc059c83d2d0ddf510731713a59f5 (MD5) 3. Figura 17 - Mapa A3_formas do relevo.jpg: 7807858 bytes, checksum: 3a0c448103fffc374c328468dc9501af (MD5) 4. Figura 18 - MapaA3_hipsometria.jpg: 7859669 bytes, checksum: 3130d732d2aa93fccd88d447343a76a1 (MD5) 5. Figua 19 - MapaA3_declividade.jpg: 10945508 bytes, checksum: 0a87633e9c47a0646edfc2fc8cfe4391 (MD5) 6. Figura 20 - MapaA3_solo.jpg: 7347123 bytes, checksum: 2b9738898a1b1bd54ff5be5a326f2fd0 (MD5) 7. Figura 22 - MapaA3_hidrografia.jpg: 10595357 bytes, checksum: 5729e737839aa0a332774eae0227f9a6 (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) Previous issue date: 2015-11-20 / From Geoarchaeology, discipline that results from the interface between Archaeology and Geosciences, with an emphasis on Physical Geography and Paleogeography, as well as the formation process of archaeological record, this research analyzed the natural factors that conditioned archaeological site formation of Miracema do Tocantins 1 (MT1), currently, under Cerrado domain. The site, seated on sandy sediments on the left bank, of the middle course of Tocantins river, Miracema do Tocantins (TO), has been occupied since the beginning of the Holocene, just over 10.000 years BP, with intervals of no occupation. This study tested the idea that, the geological substrate of the site was a member of a supposed Quaternary paleodunes field in the region, now mischaracterized by Cerrado coverage and soil that it developed. The study started by the environmental characterization of the area, with emphasis on compilation and adaptation of geology, pedology and geomorphology information, followed by data collection in the field, which included the observation of the landscape, the exposure and description of geopedological substrate, collecting material for physical, pedostratigraphics and geochronological analysis, and the observation of the sedimentary structures, to identify the site substrate and post-depositional processes related to pedogenesis. The studies and analysis of pedologic materials indicated that the bedrock’s natures is sedimentary petrographic, dated from the Lower Carboniferous, associated with a wet environment sedimentation, of marine and fluvial facies; with absence of cross stratification, typical of wind dunes; and the sandy pedologic material exhibits textural homogeneity with medium sand fraction domain, is poorly sorted, of subrounded grains, subangular and high sphericity, but asymmetrically positive pattern. The soil morphology and composition exhibited progressive pedogenetic process without lithological or erosive discordance, with grains exposed to solar radiation at about 9.100 years and 4.870 years BP, according to OSL dating. In conclusion, the sandy material of the soil site comes from the change of the source material from rocks inherited from Carboniferous formation, giving rise to Quartzarenic Neosol, which was reworked during the Holocene by gravity displacement (colluvial deposition) and low-power wind process (not formed dunes), covering the layers of archaeological occupation dated from 10.530 years BP and 5.980 years BP. / A partir da Geoarqueologia, disciplina que resulta da interface entre a Arqueologia e as Geociências, com ênfase na Geografia Física e Paleogeografia, bem como, nos processos de formação do registro arqueológico, esta pesquisa analisou fatores naturais que condicionaram a formação do sítio arqueológico Miracema do Tocantins 1 (MT1), atualmente sob domínio de Cerrado. O sítio, implantado sobre sedimentos arenosos na margem esquerda do médio curso do rio Tocantins, município de Miracema do Tocantins (TO), foi ocupado desde o Holoceno Inicial, há pouco mais de 10.000 anos AP, com intervalos de não ocupação. O presente estudo testou a ideia de que o substrato geológico do sítio era integrante de um suposto campo de paleodunas Quaternárias na região, atualmente descaracterizado pela cobertura de Cerrado e de solos que nele se desenvolveram. O estudo iniciou-se pela caracterização geoambiental da área, com ênfase na compilação e adaptação das informações sobre a geologia, pedologia e geomorfologia, seguido do levantamento de dados em campo, que incluiu a observação da paisagem, a exposição e descrição do substrato geopedológico, a coleta de material para análises físicas, pedoestratigráficas e geocronológicas, além da observação de estruturas sedimentares visando identificar o substrato do sítio e os processos pós-deposicionais relacionado à pedogênese. Os estudos e as análises dos materiais geopedológico indicaram que o substrato rochoso é de natureza petrográfica sedimentar datado do Carbonífero Inferior, associada à sedimentação em ambiente úmido, de fácies marinha e fluvial, com ausência de estratificações cruzadas típicas de dunas eólicas; e que o material pedológico arenoso apresenta homogeneidade textural com domínio da fração areia média, é mal selecionado, com grãos subarredondados, subangulosos de alta esfericidade, mas de padrão assimetricamente positivo. A morfologia e constituição do solo exibiram processo pedogenético progressivo sem discordância litológica ou erosiva, com grãos expostos à radiação solar há cerca de 9.100 anos AP e 4.870 anos AP, segundo a datação LOE realizada. Concluiu-se que, o material arenoso do solo do sítio é proveniente da alteração do material de rochas herdadas das formacões Carboníferas, dando origem ao Neossolo Quartzarênico, o qual foi retrabalhado no Holoceno por deslocamento gravitacional (coluvionamento) e processo eólico de baixa energia (não formou dunas), soterrando as camadas de ocupação arqueológica datadas de 10.530 anos AP e 5.980 anos AP.
59

Elementos para um debate sobre o clima no Éon Fanerozoico / Elements for a climate debate in the Phanerozoic Eon

Newton Monteiro de Campos Junior 12 December 2017 (has links)
O objetivo deste trabalho de pesquisa é o de buscar entender os tempos e eventos que determinaram as grandes mudanças climáticas no Éon Fanerozoico. Técnicas são constituídas, metodologias estabelecidas, e por vezes são aceitas como sendo as verdades científicas. Com as inovações nas técnicas, com o mudar das ciências, mudam as evidências, mudam as verdades, fazendo mudar nossa percepção do passado. Este trabalho apresenta elementos para um debate sobre o clima da Terra no Fanerozoico, estabelecido a partir de pesquisas bibliográficas sobre evidências passadas e atuais. / The goal of this research work is to understand the times and events that determined the great climatic changes in the Phanerozoic Eon. Techniques are constituted, methodologies are established, and are sometimes accepted as scientific truths. With innovations in techniques, with the change of science, change the evidence; change the truths, making change our perception of the past. This paper presents elements for a discussion on the Earth\'s climate in Phanerozoic established from bibliographical research on past and current evidences.
60

Neogene fluvial deposits along the south-west coast of South Africa understanding the palaeoclimate through proxies

Sciscio, Lara January 2011 (has links)
Branched glycerol dialkyl glycerol tetraether (GDGTs) membrane lipids have been used as a new proxy for the reconstruction of terrestrial palaeoclimates. These biomarkers (or molecular ‗fossils‘) in conjunction with palynology, have been effective in the novel analysis of Miocene organic-rich sediments from three South African west coast sites at Rondeberg, Noordhoek and Langebaanweg. Lastly, a Quaternary south coast site at Rietvlei, South Africa, was also studied to further elucidate the extent of use of this new proxy. The fluvial peat and organic-rich deposits of the Elandsfontyn Formation (Sandveld Group) were investigated at Noordhoek, Langebaanweg and Rondeberg to provide new evidence for the climate and vegetation patterns during Miocene in this region. Drill-core and quarry samples from all four sites were freeze-dried, powered, and prepared for biogeochemical and palynological analyses. The methylation index of branched tetraethers (MBT) and cyclisation ratio of branched tetraethers (CBT) proxies were used to calculate the mean annual air temperature (MAAT) and pH values of the organic-rich horizons at time of deposition. The Branched versus isoprenoid index of tetraethers (BIT) was used to assess the relative contributions of marine archaeal and terrestrial bacterial tetraethers, and thereby assess the validity of the MBT, CBT and calculated palaeoenvironmental factors. The results presented in this thesis suggest that the use of the MBT/CBT proxy has significant potential in southern Africa, and may complement previously attempted palaeoclimatic and palaeoecological studies of Neogene-aged South African sediments. This type of research has the capacity to provide palaeoenvironmental information where other proxies may be absent. Results indicate that all sites yielded branched tetraether membrane lipids with the exception of Rondeberg, where GDGTs were below detection as a result of poor preservation conditions. Palynological investigation confirmed proxy derived temperatures. Furthermore palynomorph analyses supplemented earlier studies of the Noordhoek site and were piloted for the Rondeberg site, reaffirming alternating sequences of tropical and subtropical palynofloras. The MAATs, likewise, show variability and pronounced trends through time at the Langebaanweg and Noordhoek sites, generally corresponding with the variation and diversity of the pollen population. The terrestrial MAAT results appear to compliment Southern Hemisphere sea level changes associated with Antarctic glaciations. Additionally, this data shows a pattern similar to the Southern and Northern Hemisphere marine isotope records of relative fluctuations in the global climate and sea level change from the early to middle Miocene. The application of these past climate change indicators have been proved to be useful in the reconstruction of South Africa Miocene palaeoclimates, and may aid in understanding the consequences of climate change in the Cape region.

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