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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.
241

Evolução morfométrica do Arroio Chuí no Sistema Laguna-Barreira, Sul da Planície Costeira do Rio Grande do Sul

Oliveira, Rafael Mastracusa de January 2014 (has links)
O conhecimento das estruturas, feições e formas numa bacia de drenagem é parte integrante do reconhecimento de sua evolução e dinâmica. Abordando a avaliação geomorfológica e dinâmica, destacamos todos os fatores físicos ambientais inerentes aos processos de formação das estruturas e feições. O presente trabalho tem como objetivo principal propor uma caracterização morfométrica da microbacia do arroio Chuí a partir da identificação do divisor de águas adjacente ao arroio Pastoreio, na região sul do estado do Rio Grande do Sul. A identificação da nascente do arroio, foi realizada preliminarmente pela análise em imagens do satélite Landsat 5 sensor TM do ano 2009 associado a dados do modelo digital de elevação (SRTM), sendo posteriormente identificado por observações em campo. Em campo, foi realizado levantamento topográfico na região do divisor de águas com a finalidade de melhor caracterização das suaves variações morfológicas da área. Em laboratório, foram processados e refinados os dados coletados em campo para modelagem tridimensional da área do divisor de águas dos arroios Chuí e Pastoreio. Em ambiente de SIG (Sistemas de Informações Geográficas) foram realizadas interpolações de cotas altimétricas dos pontos coletados em campo utilizando-se os métodos da krigagem e TIN (triangulated irregular network). Através da análise dos modelos tridimensionais gerados, foi identificado o ponto divisor de águas dos arroios, sendo determinante para a posterior delimitação da microbacia do arroio Chuí. A partir da identificação do divisor de águas e conhecimento da nascente do arroio Chuí, foi possível a definição do limite superior da microbacia, e assim caracterizar com maior precisão suas formas e dimensões. Com o uso dos dados do SRTM corrigidos, para a região sul do estado, foram geradas curvas de nível com precisão de 5m, interpolando suas cotas mais elevadas com a ferramenta Watershed (ArcGIS 10®) e definindo-se a área da microbacia do arroio Chuí com 58.796,72ha. Tais métodos de trabalho mostraram-se eficazes na caracterização morfométrica da área de estudo e proporcionaram subsídios ao mais preciso dimensionamento da microbacia do arroio Chuí, acarretando no melhor manejo dos recursos naturais dispostos. / The knowledge of the structures, features and forms a drainage basin is part of the recognition of his evolution and dynamics. Addressing the geomorphological and dynamic evaluation, we highlight all physical environmental factors inherent to the formation of structures and features. This paper has the main objective to propose a morphometric characterization of the Arroio Chuí basin from the identification of the watershed adjacent to Arroio Pastoreio, the southern state of Rio Grande do Sul. Identifying the source of the Arroyo Chuy, was preliminarily performed by analysis on satellite image Landsat 5 sensor TM of 2009 associated with the digital elevation model (SRTM and later identified by survey in field. In the field, topographic survey was conducted in the watershed region in order to better characterize the soft morphological variations of the area. In the laboratory, were processed and refined data collected in the field for three-dimensional modeling of the watershed of the Arroio Chui and Arroio Pastoreio. In the GIS (Geographic Information Systems) interpolations of elevations points collected in the field using the methods of kriging and TIN (triangulated irregular network) were performed. Through the analysis of three-dimensional models generated, the dividing point of the rivers of waters, being decisive for the further delineation of the Arroio Chuí basin was identified. From the identification of the watershed and the source of knowledge Arroyo Chuy, we define the upper limit of the basin, and so more accurately characterize their shapes and dimensions. With using a digital elevation model SRTM adjusted of the southern state, level curves were generated with an accuracy of 5m, interpolating their highest values with the Watershed tool (ArcGIS®10) and defining the area of the Arroio Chuí basin to 58796.72ha. Such working methods were effective in morphometric characterization of the area and provided subsidies to more accurate sizing of the Arroyo Chuy basin, resulting in better management of natural resources arranged.
242

Seleção de areas potenciais para recursos hidricos na bacia hidrografica do Rio Paraiba do Sul, São Paulo - Brasil / Selection of potential areas for hydrical resource in the hydrographic basin of Rio Paraiba do Sul, São Paulo - Brazil

Alves-Costa, Marcello 31 August 2006 (has links)
Orientador: Sueli Yoshinaga Pereira / Dissertação (mestrado) - Universidade Estadual de Campinas, Instituto de Geociencias / Made available in DSpace on 2018-08-07T22:08:31Z (GMT). No. of bitstreams: 1 Alves-Costa_Marcello_M.pdf: 2665030 bytes, checksum: 0feddd1783e5e1bdf0ac7c72e648b541 (MD5) Previous issue date: 2006 / Resumo: A necessidade de efetivação de políticas públicas que dêem suporte a um desenvolvimento sustentável, nos tempos atuais é uma premissa que deve ser seguida. O controle e o direcionamento das ações do homem sobre seu espaço devem ser prioritários. Áreas como as bacias hidrográficas devem ser vistas com maior detalhamento, pois em geral, as mesmas apresentam uma capacidade de suporte às transformações da paisagem, de caráter limitado. Transformações estas que muitas vezes afetam o regime das águas em uma bacia hidrográfica e, por conseguinte as condições de qualidade de vida de uma região. O poder público vem apresentando projetos que muitas vezes visam somente o ¿desenvolvimento¿ enquanto o local exige uma política sustentável referente ao meio ambiente. Deteriorização de materiais cartográficos, ausência de informações espaciais de auxilio a pesquisa são fatores básicos. Estes problemas podem ser visualizados em muitas regiões do país entre elas a região da Bacia Hidrográfica do Rio Paraíba do Sul ¿ São Paulo ¿ Brasil. Esta área apresentou e vem apresentando uma dinâmica de transformação muito acelerada. Cenário dos ciclos econômicos do café, pecuária leiteira e industrialização, a região do Vale do Paraíba conta com uma demanda crescente por recursos hídricos, porém, o que se observa é a falta de políticas públicas efetivas de regulamentação da expansão urbana e de controle do uso do recurso natural, água. Neste sentido, visando suprir a carência material de informações e, também de uma metodologia de auxilio ao planejamento territorial elaborou-se este trabalho. Com base nos princípios teóricos da ecologia da paisagem e segundo o potencial participativo no processo de infiltração de cada elemento que compõe este cenário (Relevo, Cobertura Vegetal, Pluviosidade, Solos e Geologia) propõe-se a integração dos mesmos. Visando detectar as áreas com maior e menor capacidade relativa de infiltração e, por conseguinte auxiliar o desenvolvimento de planos de planejamento e zoneamento territorial na bacia Hidrográfica do Rio Paraíba do Sul ¿ São Paulo ¿ Brasil / Abstract: The necessity of Public Political that give support to a sustainable development, in the current times is a premise that must be followed. The control and the aiming of the actions of the man on this space must be with priority. Areas as the hydrographic basins must be seen with bigger detailing, therefore in general, the same ones present a capacity of support to the transformations of the landscape, of limited character. Transformations these that many times affect the regimen of waters in a hydrographic basin, therefore the conditions of life quality of a region. The public power comes presenting projects that many times only aim at the ¿development¿ while the place demands one referring sustainable politics to the environment. These problems can be visualized in many regions in Brazil, between them the region of the hydrographic basin of Rio Paraíba do Sul- São Paulo - Brazil. This area presented and comes presenting a dynamics of transformation very sped up. Scene of the several economic cycles (coffee, cattle milkmaid and industrialization) the region of the Valley of the Paraíba counts on an increasing demand for hydric resources, however, what if it observes is the lack of public politics effective of regulation of the urban expansion and control of the use of the natural resources, water. In this direction, aiming at to supply the material lack of information and, also of a methodology of assist to the territorial planning elaborated this work. On the basis of the theoretical principles of the landscape ecology and according to participation in the process of infiltration of each element that composes this scene (Relief, Vegetal Covering, Rainfall, Soil and Geology). Aiming at to detect the areas with greater and minor relative capacity of infiltration and, therefore to assist the development of planning plans and territorial zoning in the hydrographic basin of Rio Paraíba do Sul - São Paulo - Brazil / Mestrado / Administração e Politica de Recursos Minerais / Mestre em Geociências
243

Source rock characterization of the organic rich intervals of the Taranaki Basin, Offshore New Zealand

Amansure, Giovanni Ricardo January 2015 (has links)
>Magister Scientiae - MSc / The Taranaki Basin is a large (ca. 330,000 km²) sedimentary basin found along the west coast of the northern island of New Zealand. The basin lies partly onshore but mostly offshore below the broad continental shelf to the west of central North Island. The Taranaki Basin is the first sedimentary basin to be explored in New Zealand and is currently New Zealand’s only hydrocarbon producing basin, with approximately 418 million barrels (MMbbl) of oil and 6190 billion cubic feet (bcf) of gas produced by the end of 2011. Most of New Zealand’s known oil and gas accumulations are geochemically typed to coaly facies of Late Cretaceous and Paleogene ages. The main objective of this thesis is to characterize the source rock quality of the organic rich intervals of the Taranaki Basin, namely, the Wainui Member of the North Cape Formation and the Rakopi Formation. The Rakopi Formation comprises terrestrially deposited coal measures, while the North Cape Formation is generally composed of marine rocks. These Formations make up the Pakawau Group. The objective will be achieved using two key methods. Firstly, the derivation of TOC logs using Passey’s log overlay method (Passey et al., 1990) and secondly, the generation of source rock quality maps (i.e. source rock richness mapping and source potential index mapping). This will integrate concepts relating to petrophysical wireline logs, seismic interpretation, core log information, geochemical analysis, depth mapping and isopach mapping. The results obtained from this study confirms the petroleum potential of the organic rich intervals of the Taranaki Basin. Using Passey’s method it was shown that excellent average percent TOC values are encountered for both the Wainui Member of the North Cape Formation and the Rakopi Formation. From source potential index mapping, it can be concluded that the Rakopi formation has a high source potential index (>1000SPI) on the continental shelf, which indicates that it has excellent potential for petroleum generation. The Wainui Member however, shows less potential for petroleum generation on the shelf, this being attributed to generally low net thicknesses on the shelf.
244

Storm water pollution patrol: A thematic unit for use in elementary classrooms

Sánchez, Linda Ann 01 January 1996 (has links)
No description available.
245

The Evaluation of Subsurface Fluid Migration using Noble Gas Tracers and Numerical Modeling

Eymold, William Karl January 2020 (has links)
No description available.
246

Sedimentary record of tectonic growth along a convergent margin: Insights from detrital zircon geochronology of Mesozoic sedimentary basins and modern rivers in south-central Alaska

Cooper R Fasulo (8067611) 02 December 2019 (has links)
<p>This study presents new detrital zircon geochronologic data from Jurassic to Cretaceous sedimentary basins and modern rivers in south-central Alaska in order to examine the sedimentary record of magmatism and tectonics associated with the Mesozoic to Cenozoic growth of the southern Alaska convergent margin. Jurassic to Cretaceous strata of the Wrangell Mountains, Nutzotin, and Wellesly basins formed coeval with the Mesozoic accretion of the Wrangellia composite terrane (WCT) to the continental margin. New detrital zircon data from the Wrangell Mountains and Nutzotin basins demonstrate that these basins were derived primarily from sources associated with the WCT, with little to no derivation from continental margin sources. Detrital zircon ages from the Wrangell Mountains and Nutzotin basins are very similar, suggesting that these basins may have initially formed in a connected retroarc basin system. New detrital zircon data from the Wellesly basin show that the basin was source chiefly from continental margin sources. These ages show that the Wellesly basin is not related to the Nutzotin basin as previously suggested, and may be genetically related to the Kahiltna basin; this suggests that ~330-390 km of post-collisional strike-slip offset occurred along the Denali Fault. Comparing our new data with a regional detrital zircon database from similar-aged depocenters shows that there is a strong provenance and temporal link between outboard and inboard depocenters, with these depocenters being sourced from the same magmatic arcs from the late Jurassic to the late Cretaceous. Our findings from these comparisons are most consistent with a scenario where the WCT was accreted to the margin along an eastward-dipping subduction zone, in contrast to recent suggestions that the accretion was the result of westward-dipping subduction. New and previously published detrital zircon ages from the Tanana, Matanuska-Susitna, and Copper River watersheds in south-central Alaska document the major magmatic episodes that occurred along the southern Alaska convergent margin. These magmatic episodes display a periodicity that is similar to documented cyclic magmatic patterns in other regions along the Cordilleran margin, suggesting similar processes may be occurring margin-wide. The magmatic record of south-central Alaska can also be compared with the magmatic record of other regions in the northern Cordillera such as the Coast Plutonic Complex in British Columbia and the western Alaska Peninsula, which shows a spatial and temporal relationship of magmatism along the entire northern Cordilleran margin.</p>
247

Characterization of Roadway Stormwater System Residuals for Reuse and Disposal Options

Jang, Yong C., Jain, Pradeep, Tolaymat, Thabet, Dubey, Brajesh, Singh, Shrawan, Townsend, Timothy 15 March 2010 (has links)
The chemical characterization of sediments accumulated in catch basins and stormwater ponds provides important information for assessing risks associated with management of these residuals upon removal of accumulated deposits in stormwater systems. In this study, over a period of 15 months, more than 150 residual samples were collected from 77 catch basin units and 22 stormwater ponds from 16 municipalities throughout the state of Florida. Concentrations (mg/kg) of metals and metalloids (arsenic, barium, cadmium, chromium, copper, lead, mercury, nickel, selenium, silver, and zinc) and trace organics (volatile organics, semi-volatile organics, herbicides, and pesticides) in the sediments were measured. In addition, the synthetic precipitation leaching procedure (SPLP) was utilized to evaluate pollutant leachability risk for a subset of the samples collected. Measured pollutant concentrations were compared to corresponding risk-based guidelines in Florida (i.e., Florida soil cleanup target levels) to assess potential human health risks of beneficial use of these residuals through land application. Leached concentrations were compared to risk-based water quality guidelines (i.e., Florida groundwater cleanup target levels) to examine the potential for groundwater contamination. Although several metals (arsenic, barium, chromium, copper, nickel, lead, and zinc) were routinely detected in the catch basin and stormwater pond sediments, their concentrations were generally lower than the Florida's risk-based cleanup target levels for soils. A small number of organochlorine compounds (e.g., 4,4′-DDE, 4,4′-DDT) were detected, but only in a limited number of the samples (less than 10%); leaching of trace organic pollutants above the Florida risk-based groundwater thresholds was rare. The results suggest that when land-applied or beneficially used, these residuals are not expected to pose a significant threat to human health or the environment and the results of this research will provide stormwater managers and environmental management authorities with a useful resource to examine proper disposal and beneficial use of catch basin and stormwater pond sediments.
248

Red Sea Physicochemical Gradients as Drivers of Microbial Community Assembly

Barozzi, Alan 02 1900 (has links)
Environmental gradients exist at global and local scales and the variable conditions they encompass allow the coexistence of different microbial assemblages. Studying gradients and the selection forces they enclose can reveal the spatial succession and interactions of microorganisms and, therefore, how they are assembled in functionally stable communities. By combining high-throughput sequencing technology and laboratory experimental approaches, I investigated the factors that influence the microbial community assemblages in two types of environmental gradients in the Red Sea. I have studied the communities in the chemoclines occurring at the transition zones along the interfaces between seawater and the Deep Hypersaline Anoxic Brines (DHABs) at the bottom of the Red Sea. Across these chemoclines salinity increases of 5-10 times respect to the overlying seawater. I compared the microbial community diversity and metabolisms in the chemoclines of five different DHABs, finding different microbial community compositions due to the different DHABs characteristics, but the same succession of metabolisms along the five interfaces. From the Suakin Deep brine, I assembled the genome of a novel bacterial phylum and revealed the metabolic features that allow this organism to cope with the challenging variable conditions along the chemocline. In an alternative environmental system, I studied the effect of different thermal regimes on the microbiome of coastal sediment exposed to different yearly ranges of temperature variation. Sediment bacterial communities living under larger temperature variations are more flexible and can grow under a larger range of thermal conditions than communities experiencing narrower temperature ranges. My results highlight the large metabolic flexibility of microorganisms and their capacity to efficiently self-organize in complex functional assemblages under extreme ranges of environmental conditions.
249

Spatial and Temporal Variations of the Pilot Valley Playa Interpreted From Remotely Sensed Images

Doremus, Llyn 01 May 1992 (has links)
In the Basin and Range Province, the geologic regime of the Pilot Valley, linear trending block faults have isolated many valleys both topographically and hydrologically. Discharge from these arid, closed basins occurs only as evaporation. Minerals dissolved in discharging fluid are precipitated at the valley floor as the liquid evaporates. The resulting salt flats and high density brines are known as playas. The Pilot Valley Playa surface was sampled concurrently with the recording of a Thematic Mapper remotely sensed image to define the surface conditions that correspond to image data. An association was found between the band 7 (infrared wavelength radiation) image data and the measured depth to water; and between the visible wavelength data and the evaporite mineral deposits on the playa. The specific gravity of the shallow subsurface brine was found to increase as the liquid brine surface approached the elevation of the valley floor. By using the observed relationships, three remotely sensed images were interpreted with respect to temporal changes in the areal extent of playa evaporite deposits and water depth between 1984 and 1988. The visible wavelength data indicated that the areal extent of the evaporite deposits diminished during the study period. The water level at the playa margins was interpreted to have dropped, and at the playa center to have remained stable. These interpretations suggest that a decrease in the extent of evaporite deposition is related to a drop in the water level around the playa margins. The interpreted changes of the playa surface are used to draw the following conclusions about the hydrology of the Pilot Valley. The distinct variation in depth to water around the playa margin suggests that these areas are influenced by the discharge from the surrounding ranges. The relatively stable water depth in the central playa and the associated thicker evaporite deposits suggest that the subsurface brine acts here as a buffer to discharge variations. If the temporal changes of the playa margins do result from discharge variation, the discharge zone at the base of the Silver Island Range is wider than that of the adjacent, higher elevation Pilot Range.
250

Sources of Water and Solutes to the Salar de Atacama, Chile: A Coupled Hydrologic, Geochemical, and Groundwater Modeling Study

Corenthal, Lilly G 23 March 2016 (has links)
Focused groundwater discharge in endorheic basins provides opportunities to investigate mechanisms for closing hydrologic budgets in arid regions. The Salar de Atacama (SdA), a closed basin in northern Chile, has accumulated over 1800 km3 of halite and a lithium-rich brine since the late Miocene primarily through evapotranspiration of groundwater. The hydrologic balance of SdA and sources of water and solutes required to explain this deposit are not well constrained. An adapted chloride mass balance method drawing on a database of over 200 water sample sites is applied to a remotely-sensed precipitation dataset to estimate spatially-distributed modern groundwater recharge. Comparing groundwater recharge to evapotranspiration in a steady-state water budget constrains potential regional-scale watersheds on the Altiplano-Puna Plateau. The sodium mass balance of the deposit is used to predict long-term water discharge from the basin and place modern fluxes in a paleo-hydrologic context. A 2D groundwater model informed by published paleoclimate reconstructions evaluates whether draining groundwater storage contributes to the modern hydrologic system. Modern recharge from precipitation in the topographic watershed is extremely small compared to evapotranspiration. The missing water is sourced from precipitation in an area over 4 times larger than the topographic watershed, and groundwater recharged during wetter periods in the late Pleistocene is still actively draining and discharging from storage without a corresponding input into the system. These results have implications for lake-level based paleoclimate reconstructions, conceptualizations of watershed boundaries and water resource management.

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