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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.
311

Análise sismoestratigráfica da seção rifte da Bacia de Campos

Ene, Patrycia Leipnitz January 2014 (has links)
A Bacia de Campos está limitada pelo Alto de Vitória ao Norte e pelo Alto de Florianópolis ao sul, possuindo uma área de aproximadamente 100.000 km2. Sua seção rifte é composta pela porção basal a mediana do Grupo Lagoa Feia, e inclui a principal rocha geradora da bacia, reconhecidamente rica em matéria orgânica, sendo a maior produtora de hidrocarbonetos do Brasil, e rochas reservatório carbonáticas. O presente estudo foca sua análise no intervalo rifte, onde foi realizada uma interpretação e mapeamento sistemático de linhas sísmicas 2D em uma área chave da bacia. Esta análise é baseada em adaptações de modelos já existentes de evolução de bacias rifte, e nos conceitos de estratigrafia de sequências aplicados à sismoestratigrafia. Através da interpretação e mapeamento das seções sísmicas, foi possível elaborar um modelo evolutivo para a fase inicial da Bacia de Campos, com a elaboração de uma carta cronoestratigráfica e estabelecimento dos tratos de sistemas que distinguem as diferentes fases de evolução dos meio-grábens reconhecidos. O resultado foi a delimitação de três tratos de sistemas tectônicos, que permitiram uma compreensão detalhada da complexa evolução e desenvolvimento das calhas da Bacia de Campos durante a fase rifte. / The Campos Basin is limited northward by the Vitória High and southward by the Florianópolis High, with an area of approximately 100,000 km2. The rift section in the Campos Basin comprises the basal and median portions of the Lagoa Feia Group, and includes the main source rocks in the basin, which is known to be rich in organic matter and is the best hydrocarbon producer in Brazil, as well as carbonate reservoir rocks. The present study focuses its analysis on the rift section, where a systematic mapping and interpretation of 2D seismic lines in a key area of the basin was carried out. This analysis is based on adaptations of existing evolution models for rift basins, and the concepts of sequence stratigraphy applied to seismic stratigraphy. Through the interpretation and mapping of seismic sections, it was possible to propose an evolution model for the initial phase of the Campos Basin, with the construction of a chronostratigraphic chart and the establishment of systems tracts that distinguish different stages on the evolution of the recognized half-grabens. The result was the delimitation of three tectonic systems tracts that allowed the detailed understanding of the complex evolution and trough development of the Campos Basin during the rift phase.
312

Análise do atendimento às demandas hídricas superficiais no reservatório da usina Bariri (SP) utilizando o simulador computacional Mike Basin / Analysis of the service demands on surface water reservoir of the Bariri (SP) power plant using the computer simulator Mike Basin

Victor Pioltine 16 October 2009 (has links)
É indiscutível a importância da disponibilidade hídrica tanto quantitativa como qualitativa para o desenvolvimento adequado de determinada região inserida em bacias hidrográficas. Tal desenvolvimento deve ser planejado e administrado visando à minimização dos conflitos ocasionados pelos usos múltiplos da água, de modo que todas as demandas possam ter o máximo de confiabilidade em seus respectivos atendimentos e, também, possa haver a maximização dos benefícios sociais, econômicos e ambientais na região. Diante disso, este trabalho buscou analisar o atendimento às demandas hídricas superficiais para os diversos setores usuários localizados na área de drenagem do reservatório da usina Bariri (SP). Por meio da aplicação do simulador hidrológico MIKE BASIN foi analisado o desempenho do reservatório da usina Bariri em atender às demandas hídricas superficiais para o ano de 2008 e para cenários futuros com anos horizontes de 2010, 2025 e 2050. A partir deste estudo concluiu-se que há volume de água suficiente para atender às demandas hídricas superficiais na região de estudo e também para atender a produção energética na usina Bariri. O software Mike Basin mostrou-se ser uma ferramenta muito útil para a gestão dos recursos hídricos. / It is clear the importance of water availability both qualitative and quantitative for the development of a region inserted into a catchment area. This development must be planned and managed to the minimization of conflicts caused by multiple uses of water so that all demands have the maximum reliability in their care and also may be the maximization of social, economic and environmental in the region. Thus, this study, analyzed the surface water and its demands for different sectors users located in the drainage of the reservoir of the Bariri (SP) power plant. Through the application of hydrological simulation MIKE BASIN was examined system performance in meeting the demands for water current conditions (year 2008) and for future scenarios with years to 2010, 2025 and 2050. From this study, it is concluded that volume of water needed to meet the demands water surface in the region of study and energy production reached its goal in every period simulated.
313

Revisão taxonômica e relações filogenéticas do gênero Leporacanthicus Isbrücker & Nijssen, 1989 (Siluriformes, Loricariidae) / Taxonomic review and phylogenetic relationships of the genus Leporacanthicus Isbrücker & Nijssen, 1989 (Siluriformes, Loricariidae)

Carine Cavalcante Chamon 24 October 2007 (has links)
Uma revisão taxonômica gênero Leporacanthicus Isbrücker & Nijssen, 1989 é apresentada, bem como uma hipótese filogenética de relacionamento das espécies, e de seu posicionamento dentro da tribo Ancistrini. Quatro espécies distribuídas no planalto Brasileiro e das Guianas, bacias Amazônica e do Orinoco são consideradas válidas: L.galaxias (rios Tocantins, Guamá e Orinoco); L. joselimai (rios Tapajós e Curuá-Una); L. heterodon (rio Xingu); e L. triactis (rio Orinoco). A análise resultou em dois cladogramas igualmente parcimoniosos com 336 passos (IC=0,43; IR=0,66), do qual foi gerado uma árvore de consenso estrito. O monofiletismo de Leporacanthicus é corroborado por 14 sinapomorfias; dentro do gênero foi obtida a seguinte topologia (L. galaxias (L. triactis (L. heterodon, L. joselimai))). Os resultados apresentados aqui sugerem que Pseudacanthicus representam o grupo irmão de Leporacanthicus, diferindo de propostas anteriores obtidas com caracteres morfológicos e/ou moleculares. / A taxonomic review of the genus Leporacanthicus Isbrücker & Nijssen, 1989 is presented, as well as a phylogenetic hypothesis of species relationships, and it position within the tribe Ancistrini. Four species distributed in the Brazilian and Guiana Shields, Amazon and Orinoco Basins, are recognized as valid: L.galaxias (rios Tocantins, Guam and Orinoco); L. joselimai (rios Tapajós and Curuá-Una), L. heterodon (rio Xingu); e L. triactis (rio Orinoco). The phylogenetic analysis resulted in two cladogramas equally parsimonious with 336 steps (CI=0,43; RI=0,66), from which a strict consensus tree was generated. The monophyletism of Leporacanthicus is corroborated by 14 synapomorphies; within the genus the following topology was obtained: (L. galaxias (L. triactis (L. heterodon, L. joselimai))). The results presented herein suggest that Pseudacanthicus is considered to be the sister-group of Leporacanthicus, differing from previous hypothesis obtained using molecular and/or morphological dada.
314

The nature of the western margin of the Witwatersrand Basin

Van der Merwe, Roelof 07 October 2014 (has links)
D.Phil. (Geology) / The tectonic evolution of the "western margin" of the Witwatersrand Basin is examined and indications are that it has undergone a long and complex history. In order to examine the nature of Witwatersrand-age structures, structures in both pre- and post-Witwatersrand sequences are also examined. Rocks of the ±3074 Ma Dominion Group were subjected to a tectono-metamorphic event prior to the deposition of Witwatersrand strata on an angular unconformity. An oligomictic conglomerate is sporadically developed at the base of the Witwatersrand Supergroup. PreVentersdorp structures in Witwatersrand strata are developed in two distinct trends, north-south and northeast-southwest. The relationship between the two directions of folds and thrust faults are best explained within a regional, sinistral transpressive shear couple; the north-south faults are sinistral strike-slip faults and the northeast-southwest trending folds and thrust faults are secondary structures associated with the strikeslip faults. The implications of this model are that Witwatersrand sedimentation was probably controlled by lateral movements on north-south trending faults and not by thrust faults in a foreland system as suggested by the most recent models of Witwatersrand basin development. Post-Witwatersrand deformation is complex. Southeastward verging, pre-Ventersdorp, thrust faults were reactivated as normal faults during Platberg times and the resultant half-grabens were infilled by conglomerates of the Kameeldoorns Formation. Later deformational events include eastward verging post-Ventersdorp thrust faults and post-Transvaal normal and strike-slip faults. It can be demonstrated that the majority of this later fault movements took place along pre-existing fault planes and therefore tectonic inversion is a fundamental process in the evolution of the Witwatersrand Basin. Clearly therefore, the present distribution of Witwatersrand strata does not reflect the original basin geometry, it is the result of several periods of basin inversion and no basin margins can be defined.
315

Risk assessment of inhaled and ingested airborne particles in the vicinity of gold mine tailings : case study of the Witwatersrand Basin

Maseki, Joel 25 November 2013 (has links)
M.Sc. (Geography) / Severe Aeolian deposition of windblown dust from mine tailings storage facilities (TSFs) is a common phenomenon on the Witwatersrand, especially during the spring windy season. For communities around tailings storage facilities, this poses health and environmental challenges. This dissertation estimates the risk of adverse health effects resulting from human exposure to hazardous elements in particulate matter (sub 20 μm diameter) for selected tailings storage facilities: East Rand Gold and Uranium Company (ERGO); East Rand Proprietary Mine (ERPM); Crown Gold Recoveries (CGR) and Durban Roodepoort Deep (DRD). Samples of surface material from these TSFs were analysed for heavy metal content using the ICP-MS method. Other than the expected gold, five heavy metals (arsenic, cadmium, chromium, lead and uranium) exhibited enrichments in the tailings material significantly above average (greater than a factor of 2) crustal composition. These elements were selected for comprehensive risk assessment through airborne exposure routes. The mean ambient particulate concentration in air of 540 μg m-3 (used in the risk calculations) was based on a conservative worst-case exposure scenario. U.S. Environmental Protection Agency (US EPA) risk assessment methods were used to determine the inhalation and ingestion hazard quotient and hazard indices for adults and children. The sum of the hazard indices was below the non-cancer benchmark (hazard indices 1.0) considered to be acceptable for a lifetime exposure. The risk cancer included the excess life cancer risk for the inhalation and the ingestion risk. The total risk for both exposures was within the range of 1 in 1 000 000 to 100 in 1 000 000 - taken as “acceptable risk” by the U.S. Environmental Protection Agency for adults and children.
316

Comprehensive fluid saturation study for the Fula North field Muglad Basin, Sudan

Altayeb, Abdalmajid I. H. January 2016 (has links)
>Magister Scientiae - MSc / This study has been conducted to accurately determine fluid saturation within Fula sub-basin reservoirs which is located at the Southern part of the Republic of Sudan. The area is regarded as Shaly Sand Reservoirs. Four deferent shaly sand lithofacies (A, B, C, D) have been identified. Using method based on the Artificial Neural Networks (ANN), the core surrounding facies, within Fula reservoirs were identified. An average shale volume of 0.126 within the studied reservoirs was determined using gamma ray and resistivity logs. While average porosity of 26.7% within the reservoirs was determined using density log and the average core grain density. An average water resistivity of 0.8 Ohm-m was estimated using Pickett plot method. While formation temperature was estimated using the gradient that constrained between surface and bottom hole temperature. Water saturation was determined using Archie model and four shaly sand empirical models, the calculation was constrained within each facies zone to specify a model for each facies, and another approach was used to obtain the water saturation based on Artificial Neural Networks. The net pay was identified for each reservoir by applying cut-offs on permeability 5 mD, porosity 16%, shale volume 0.33, and water saturation 0.65. The gross thickness of the reservoirs ranges from 7.62m to 19.85m and net pay intervals from 4.877m to 19.202m. The study succeeded in establishing water saturation model for the Fula sub-basin based on neural networking which was very consistent with the core data, and hence has been used for net pay determination.
317

Evolution of the Mio-Pleistocene forearc basin induced by the plate subduction in the Boso Peninsula, central Japan / プレート沈み込みによる房総半島新第三系および第四系前弧海盆の形成過程

Kamiya, Nana 23 March 2020 (has links)
京都大学 / 0048 / 新制・課程博士 / 博士(工学) / 甲第22424号 / 工博第4685号 / 新制||工||1731(附属図書館) / 京都大学大学院工学研究科都市社会工学専攻 / (主査)教授 林 為人, 教授 小池 克明, 准教授 村田 澄彦 / 学位規則第4条第1項該当 / Doctor of Philosophy (Engineering) / Kyoto University / DFAM
318

The Historical Development of the University of Texas of the Permian Basin, Odessa, Texas

Kern, Stephanie P. 08 1900 (has links)
The University of Texas of the Permian Basin (UTPB) is a public university that serves over 4,500 undergraduate and graduate students as a branch of the University of Texas system located in Odessa, Ector County, Texas. The UTPB was established as an upper-division and graduate school on February 4, 1969, and first opened its doors to students in September, 1973. This historical study focuses on the development and progress of the UTPB from its inception until it was elevated from an upper-level institution to a four-year university twenty-two years later. The formation, mission, and curriculum are examined as well as are faculty and student characteristics and support. This study addresses the background history of higher education in the region, the role of community and college leaders in the UTPB's creation and struggle for four-year status, and the UTPB's unique features. The study was conducted by collecting data from available primary and secondary sources. The written data were then subjected to both external and internal criticism to determine the authorship and meaning of the documents. To explain events and put the written documents in context, oral histories, given by participants, were used. The educational opportunities offered by the UTPB have enriched the lives of Ector County citizens as well as the lives of many students from surrounding counties in the region of Texas known as the Permian Basin. Additional research topics related to the UTPB as well as other educational institutions are suggested.
319

Shaping Transboundary Water Governance - How Learning Spaces Shape Transboundary River Basin Management Practices and Processes in the Omo-Turkana and Zambezi River Basins

Lumosi, Caroline Kang'ahi 23 September 2020 (has links)
This doctoral dissertation provides conceptual contributions to understanding and analysing transboundary river basin management practices and processes. The conceptual framework of this thesis is embedded in the social learning literature. This thesis builds on prior efforts by scholars (see Keen et al., 2005; Muro & Jeffrey, 2008; Newig et al., 2010; Pahl-Wostl, 2009; Reed et al., 2010; Schusler et al., 2003) to evaluate and analyze social learning processes. In particular, the concept of learning space as used in this thesis contributes to a deeper understanding of the context in which social learning occurs by combining an analysis of interactions, deliberations and reframing processes. Three research gaps are identified and addressed in this dissertation. First, conceptualisation and evaluation of social learning in emergent processes. Second, an analysis of how relational features (such as trust and shared identities) impact on social learning outcomes. Third, the lack in understanding of how contextual features (such as frames) shape social learning processes and influence transboundary river basin management practices. To address these gaps, this thesis employed case study approach of two transboundary river basins; the Omo-Turkana and Zambezi river basins in Africa. The two case studies fit a better understanding of transboundary river basin management processes and practices as both river basins are shared by different riparian states with competing interests. This thesis explores the general research question: How do learning spaces shape transboundary river basin management practices and processes? This thesis found that the success of transboundary basin cooperation lies not only in actors solving technical problems but also hugely relates to how actors interact with one another to build the needed capacity to address technical issues. As such, creating trust and shared identities, as well as paying attention to problem framing plays a considerable role in defining how actors learn. Overall, by incorporating concepts such as trust, shared identity and frames into the concept of learning space, this thesis was able to provide a better understanding of transboundary river basin management practices. Such a perspective could provide a deeper understanding of how management practices and institutions can be better designed.
320

Quaternary Amino Acid Geochronology of the Lahontan Basin, Nevada, and the Chewaucan Basin, Oregon

Bigelow, Jeffrey 01 May 1998 (has links)
Amino acid geochronology based on fossil molluscs provides a useful approach to determining the Quaternary history of Great Basin lakes. The Lahontan basin, Nevada, and the Chewaucan basin, Oregon, in the northwest corner of the Great Basin, both contained lakes during the Quaternary. The aim of this study is to improve the Quaternary geochronology in these two basins by measuring time-dependent changes in amino acids preserved in fossil molluscan shells. The abundance of D-alloisoleucine relative to Lisoleucine (All) characterizes the extent of racemization, which increases with age and Ul forms the basis of relative and correlated ages. An age-calibration curve for Vorticifex was developed using All ratios in shells from layers with radiocarbon-dated shells and with one thermoluminescence date in the Chewaucan basin. The All ratios from non-dated deposits were assigned ages from this calibration curve. The All ratios in 77 samples (-350 shells) of mainly Vorticifex were analyzed to improve the lake chronology in the Lahontan and Chewaucan basins. From the stratigraphic position, All ratios in the shells, and previously published radiometric ages, at least five and possibly six lake cycles were inferred in the Lahontan basin for the Quaternary period. Shells with highest All ratios ( -0.8) might correlate with the Rye Patch Alloformation, named for deep-lake sediments deposited in the Lahontan basin -630 ka. The next younger lake deposits are ascribed to the Eetza Alloformation. On the basis of the amino acid data, two and possibly three distinct lake expansions took place during the Eetza lacustrine episode, which lasted from -385 to 145 ka. Deposits of the Sehoo Alloformation ( -35 to 12 ka) can be differentiated from older deposits on the basis of All ratios in mollusc shells. Finally, a few shells with low All ratios near Pyramid Lake may indicate a minor lake expansion during the Holocene. Only two lake cycles were inferred from the amino acid data in the Chewaucan basin for the Quaternary period. Shells with the highest ratios correlated with the Eetza Alloformation and the shells with lowest ratios correlate with the Sehoo Alloformation. The amino acid data suggest that Lake Lahontan and Lake Bonneville experienced similar lake-level histories during the past -660 ka. The Sehoo Alloformation in the Lahontan basin broadly correlates with Bonneville Alloformation in the Bonneville basin based on All ratios and radiocarbon dates. The late and early aminozones within the Eetza Alloformation might correlate, respectively, with the Little Valley and Pokes Point Alloformations in the Bonneville basin.

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