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Search theses and dissertations gathered from participating repositories worldwide. Every result links back to the library that holds it. No account is needed.
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Showing 1 to 17 of 17 for “"surficial sediments"”.
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In-Situ Geotechnical Characterization of Soft Estuarine Surficial Sediments Using a Portable Free Fall Penetrometer
… soil conditions such as very soft estuarine sediments. This study aims to advance the analysis procedure of portable free fall penetrometers (PFFP) in soft subaquatic fine-grained soils with natural water contents greater than the liquid limit by estimating the undrained shear strength (su). …
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The occurrence and distribution of microplastics in surficial sediments and fish in a South African reservoir
Microplastics have become a major environmental concern globally due to their potential impacts on ecosystem function. They are known to be ubiquitously present, persistent and bio−accumulative, yet ecological impacts of microplastic remain poorly understood despite their ubiquity across all …
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A Comparison of Metals in Several Ahermatypic Corals and Surficial Sediments: Mobile Pinnacles and Hoffa Reef, Northcentral Gulf of Mexico
… Mn, and Ni are all slightly depleted in these sediments relative to crustal abundances. Discriminant function analyses shows that the concentrations of five elements differ between locations.</p> <p>Ahermatypic coral (106 specimens) from five genera collected from the study sites were analyzed …
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Ecosystem health in Guánica Bay and La Parguera, Puerto Rico: Remote sensing of ocean color and metal analysis of coral tissue and surficial sediments
… at its periphery. This ecosystem is affected by sediments, nutrients, and contaminants from the watershed through the Bay and into the offshore water. This project evaluates Guánica Bay and La Parguera coastal areas through remote sensing and chemical analysis to assess coastal ecosystem health. …
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Benthic foraminifera from the Orange-Luderitz shelf, southern African continental margin
… investigation of the benthic foraminifera in the surficial sediments of the continental shelf and upper slope off the Orange River mouth and the Namib Desert was undertaken as an adjunct to sedimentological and geophysical investigations being conducted by members of the Joint Geological …
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DYNAMIC EQUILIBRIUM BEACH PROFILES: FORCES OF OFFSHORE SEDIMENT TRANSPORT IN MARYLAND’S CHESAPEAKE BAY
… sediment composition, and strength of eroding sediments were also explored. The results showed that sands dominated offshore surficial sediments at most locations, even though the source sediments were mixtures of sands and muds. The observed offshore profiles were consistent with expectation …
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Hydrologic factors affecting the discharge of ground water in the Red River of the North Basin, northeastern North Dakota
… the Dakota Group. Overlying the bedrock are sediments from numerous glacial advances and lacustrine sediments from glacial Lake Agassiz. These units form confining layers over the bedrock aquifers and limit the rate of ground-water discharge from bedrock sources.</p> <p>The three mechanisms …
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Development of a Sediment Sampling Free Fall Penetrometer Add-on Unit for Geotechnical Characterization of Seabed Surface Layers
In-situ geotechnical testing of surficial sediment layers in areas of active sediment dynamics can provide essential information about physical and geotechnical variations of sediment properties with regards to active sediment remobilization processes. For example, portable free fall penetrometers …
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Spatial analysis of blue carbon in a UK Saltmarsh: Implications of carbon distribution.
… the spatial distribution of organic carbon of surficial sediments and the factors driving its production and preservation were studied at Biggar Saltmarsh, situated on Walney Island, west of Barrow-in-Furness on the north side of Morecambe Bay, England. Thirty-three sediment samples were …
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Quaternary geology of the southern part of the Grand Forks and Bemidji quadrangles
… material. A variety of fluvial and lacustrine sediments are typically inter bedded with the glacial sediment.</p> <p>On the basis of the geomorphology and topography, the south ern part of the Grand Forks and Bemidji Quadrang1es (scale 1:250,000) can be divided into the Lake-Plain Province, the …
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Extractable organics and colour in a bleached kraft mill effluent land application system and recipient ground waters
… of the system on organic contamination of sediments, aquifer materials, and ground waters. The study was carried out in four parts, investigating: (i) the behaviour of extractable organics and colour in the effluent drains and seepage basins; (ii) the penetration of extractable organics …
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The influence of sediment nutrient dynamics on the response of lake ecosystems to restoration and climate change
… availability of nutrient pools in lake bottom sediments is fundamentally important for predicting how, and over what time-scales, lake ecosystems will respond to future scenarios such as climate change, in-lake restoration or altered external nutrient loading. Through a sediment field study on …
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Past and present benthic fauna of Lake Maratoto with special reference to the chironomidae
… characteristics of a lake from knowledge of its surficial sediment chironomid remains. Dystrophic lakes were characterised by high numbers of most species, particularly Kiefferulus opalensis, Tanypodinae, Calopsectra spp. and Paucispini gera spp. but low numbers of Paratanytarsus a gameta. Clear …
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Clay petrology of Mesozoic to recent sediments of central western North Island, New Zealand
… and chemical data for Mesozoic to Recent onshore sediments and Recent western shelf surficial sediments from central Western North Island are presented with the aim of determining the significance of areal and stratigraphic variations in clay mineral distributions. Sample analysis procedures using …
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Surface Spills Associated with Oil and Gas Activities in Saskatchewan and Potential Impacts to Shallow Groundwater Resources
… to water supply wells while considering surficial geologic properties and estimating the timescales over which contaminants will infiltrate the subsurface and be transported to shallow groundwater wells. There have been 24,878 oil and PW spills reported to the Saskatchewan Ministry of …
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Geotechnical Investigation and Characterization of Bivalve-Sediment Interactions
… to reduce erosion potential. Shell hash-laden sediments should be able to better withstand shearing, thereby increasing the critical shear stress required to erode material, compared to sediment without shell hash. Habitat suitability for bivalve colonies is also an important consideration to …