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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.
251

Sedimentology of the basal Stoddart Formation (Upper Mississippian) in the area of Josephine Field, northwest Alberta

Hrabi, Robert Blair 04 1900 (has links)
<p> A sedimentogical and petrological examination of the basal sands of the Stoddart Formation in the area of Josephine field has been undertaken. The determination of the depositiianal environment and the history of sedimentation of the basal Stoddart sands are the objectives of this study. </p> <p>The thick sands at the base of the Stoddart Formation which have a blocky gamma ray response consist of fine-grained sandstone dominated by angle of repose cross-bedding. The sedimentary structures, stratification types, composition and facies relationships of these sands indicate that they are of a coastal aeolian origin.</p> <p>The compositional, textural and surface texture characteristics of these sands were studied under petrographic, cathodolumenescent and scanning electron microscopes. Observations indicate that the above criteria can be used to support the interpretation of an aeolian origin for the cross-bedded sands of the basal Stoddart Formation. </p> <p>The sands of the basal Stoddart show rapid transitions between sub-aerial and marine environments. These rapid changes are believed to be caused by sudden sea level fluctuations resulting from movement of reactivated faults in the Peace River arch area. </p> / Thesis / Bachelor of Science (BSc)
252

IMPACT OF PETROLEUM RELATED COMPOUNDS ON MESENCHYMAL STEM CELL DERIVED PROGENITOR CELLS

Gutgesell, Robert Michael January 2022 (has links)
There is concern over the impact that petroleum related compounds (PRCs) associated with mining activity in the Athabasca Oil Sands Region (AOSR) are having on local wildlife. With the increase in oil sands mining activity in the AOSR there has been a corresponding decline in the fertility of indicator species in the AOSR. One of the primary sources of PRCs in the environment is oil sands process affected water (OSPW), which is stored in tailings ponds. Several PRCs, including naphthenic acid fraction components (NAFC), have endocrine disrupting effects, which may, in part, explain reduced fertility in indicator species. For example, male North American river otters (Lontra canadensis) living in areas impacted by mining activity have lower baculum strength those unaffected by mining activity. Weaker baculums are associated with increases in fracture rates and reduced fertility. Baculum strength is maintained throughout life by bone remodeling, a process that requires the differentiation of osteoblasts. NAFCs can impact several pathways integral to the development and path selection of mesenchymal stem cells into osteoblasts or adipocytes. Therefore, the objective of this thesis was to test the hypothesis that NAFCs inhibit osteoblast differentiation and induce adipocyte differentiation from progenitor cells. We exposed osteoblast progenitor cells and adipocyte progenitor cells to NAFCs. We demonstrated that NAFCs inhibit osteoblast differentiation and activate the glucocorticoid receptor pathway. We also found that NAFCs do not induce adipogenesis in adipocyte precursor cells. Lastly, we showed that NAFCs are PPARγ ligands that inhibit the expression of PPARγ associated genes. These insights into the effects of NAFCs on osteoblast and adipocyte progenitor cells suggest NAFCs may contribute to lower baculum strength and impaired adipose tissue function of animals living in the AOSR. These effects my reduce the fertility and population of wildlife in the AOSR. / Thesis / Master of Science (MSc) / There is concern that chemicals from oil sands mining in the Athabasca oil sands region are hurting the reproductive health of animals in the wild. Some of these animals, including bears, wolves, and river otters, need a bone in their penis called a baculum to reproduce. Studies have shown that some chemicals, including those from mining activity can make the baculum bone weaker. For bone to stay strong, bone cells always need to be developing to fix the bone tissue. The goal of our study was to find how chemicals from mining activity can affect the development of bone cells. We found that a group of chemicals that come from oil sands mining called naphthenic acid fraction components (NAFCs) stop bone cells from developing and making new bone. We also know that having more fat cells in bone is associated with weaker bones. We also looked at whether NAFCs could increase the development of fat cells. However, NAFCs did not increase the development of fat cells. Together, this research shows that NAFCs can make bones like the baculum weaker by slowing the development of new bone, but not by increasing fat cells. Our research suggests that exposure to NAFCs may make baculums weaker which may be bad for the reproductive health of animals living near oil sands mining activity.
253

Boomtown Attitudes and Perceptions Non-renewable Energy Extraction Regions:North Dakota, U.S.A., Oil Shale and Alberta, Canada, Oil Sands

Raycraft, Mary D. January 2017 (has links)
No description available.
254

Seasonal Sulfur Biogeochemistry of Oil Sands Composite Tailings Undergoing Fen Reclamation

Stephenson, Kate E. 10 1900 (has links)
<p>The Athabasca oil sands produce 20% of Canada’s oil, which in turn creates trillions of cubic meters of waste. The Alberta government mandates that oil sands land be reclaimed to its natural state after mining has occurred. Syncrude Canada is currently creating a novel freshwater fen on top of a composite tailings (CT) deposit as a pilot large-scale reclamation project. CT are both microbially and sulfur rich, in addition, the fen could be a potential source of labile organics and sulfate reducing bacteria which could further stimulate sulfur cycling by microorganisms with the potential to stimulate H<sub>2</sub>S<sub>(g)</sub> generation, a health and safety concern. Therefore, this thesis examines three main research questions regarding this H<sub>2</sub>S production within the Sandhill reclamation fen: 1) Is H<sub>2</sub>S generation widespread within the porewaters of the CT and sand cap of the developing Sandhill Fen reclamation project? 2)<strong> </strong>Do microbial metabolisms capable of metabolizing Fe and S linked to H<sub>2</sub>S generation occur within CT and sand cap of the developing Sandhill Fen? and 3) Will seasonality and ongoing fen construction impact H<sub>2</sub>S generation?</p> <p>Field and experimental results herein discuss potential microbial and abiotic metabolisms and pathways that effect sulfur and iron cycling that could affect hydrogen sulfide generation within the composite tailings and developing fen during three seasonal sampling campaigns from June 2010 to July 2011. Results indicate that detectable H<sub>2</sub>S<sub>(aq)</sub> occurred in the fen porewaters during each sampling campaign, with a trend of increasing H<sub>2</sub>S<sub>(aq)</sub> concentrations as construction of the fen progressed. Further, enrichment results indicate that microbial sulfur and iron redox reactions are likely affecting the H<sub>2</sub>S<sub>(aq)</sub> generation. Experimental microcosm results indicate that the CT may contain unstable sulfur species that can contribute to H<sub>2</sub>S<sub>(aq)</sub> generation and sequestration in the CT as pyrite. Additionally, the evolution of the Sandhill Fen changed the microbial communities that were present <em>in situ</em> as well as shifted dominance of species type in environmental microbial enrichments. The putative function of these bacteria show a shift from autotrophy to increased heterotrophic metabolisms as the fen is being constructed, suggesting the addition of labile organic substrates from the peat and woody debris are both changing the dominant metabolisms and well as increasing microbial diversity to the underlying CT and sand cap of Sandhill Fen. Results of this thesis established widespread microbial Fe and S metabolisms within CT for the first time and indicated that fen reclamation will alter microbial activity with implications for S cycling within CT. Although this thesis covers a short sampling time frame, it is clear that H<sub>2</sub>S<sub>(aq)</sub> generation is an important factor to consider during large scale CT reclamation. While microorganisms are present and could be impacting Fe and S cycling, the CT materials should be investigated further in regards to their potential for H<sub>2</sub>S<sub>(aq)</sub> generation. More consideration should be given to inhibiting H<sub>2</sub>S<sub>(aq)</sub> generation or supporting FeS formation within the reclamation fen.<strong></strong></p> / Master of Science (MSc)
255

METHANE BIOGEOCHEMICAL CYCLING OVER SEASONAL AND ANNUAL SCALES IN AN OIL SANDS TAILINGS END PIT LAKE

Goad, Corey 11 1900 (has links)
This Master’s degree study examined concentration and isotopic trends of dissolved methane, isotopic trends of phospholipid fatty acids (PLFA), and generated 1st order flux calculations to identify and assess biogeochemical cycling of dissolved methane in the first full-scale demonstration of EPL technology in the Alberta Oil Sands Region (AOSR). Base Mine Lake (BML) was commissioned by Syncrude Canada Ltd. in 2012 to facilitate the long-term storage and remediation of Fluid Fine Tailings (FFT) that are generated as a result of bitumen extraction via the Clark Hot Water Extraction (CHWE) processes. The results of this project provide evidence of methane oxidation by type I methanotrophs in BML, reducing dissolved oxygen concentrations in the hypolimnion layer. The FFT layer is identified as a source zone of fermentative methanogenesis, creating saturated conditions of dissolved gases. Dissolved methane is transferred to the water column primarily by advective processes related to FFT consolidation, while diffusion is a significant secondary transfer mechanism. Dissolved methane concentrations decrease significantly across the FFT-water interface where diffusive flux rates decrease by several orders of magnitude. Concentrations decreased linearly through the hypolimnion to trace concentrations by the metalimnion, resulting in a minor enrichment of δ13C of the residual dissolved methane pool. A minor enrichment of δ13C in C14:0, C16:0, and C16:1 PLFA coincided across the same interval, indicating utilization of a less depleted carbon source further away from the FFT-water interface where dissolved methane concentrations were lower. PLFA δ13C signatures were depleted relative to expected values of typical DOC substrates, further supporting the incorporation of a depleted signature by transfer of depleted carbon from dissolved methane. / Thesis / Master of Science (MSc)
256

A toxicity assessment of sludge fluids associated with tar sands tailings /

Abdel Warith, Mostafa January 1983 (has links)
No description available.
257

Foam fractionation and air flotation treatment of a tarsand extraction wastewater

VanLeigh, Logan January 1983 (has links)
The objectives of this project were: 1) to ascertain the feasibility of using a two-stage foam separation system, with foam fractionation or air flotation as the second stage, to treat a tarsand extraction wastewater; and, 2) to evaluate the effects of four operational variables on the second stage performance. The wastewater was a tar-in-water emulsion collected during a steamflood extraction experiment conducted by the Department of Energy's Laramie Energy Technology Center on a tarsand deposit in eastern Utah. The four operational variables considered were chemical dose, hydraulic detention time, air flowrate, and temperature. To achieve these objectives a two-stage system was devised. In the first stage, polymer-aided air flotation removed the bulk of the tar. With the second-stage foam fractionation system, 16 trials were conducted using the cationic surfactant, EHDA-Br. In the second-stage air flotation system, 24 trials were conducted, eight with no polymer addition and 16 with the addition of the low molecular weight, strongly cationic polyelectrolyte, Betz 1195. Ten trials were then conducted at the set of conditions believed to give the best treatment of the water. The effluents were tested for TOC, COD, suspended solids (SS), and total solids. It was found that either of the two-stage systems would give TOC, COD, and SS reductions greater than 98 percent, although the polymer-aided air flotation system was found to be the best second stage process. The replicate trials consistently produced data very close to the best treatment achieved in the experimental trials, thus showing the reproducibility and stability of the two-stage process. / M. S.
258

Activity and kinetics of microbial extracellular enzymes in organic-poor sands of a south Texas estuary

Souza, Afonso Cesar Rezende de, 1968- 22 March 2011 (has links)
The respective kinetics of bacterial leucine aminopeptidase and [beta]-glucosidase activities were investigated to improve understanding of factors controlling activity and hydrolytic capacity in estuarine organic-poor sands. Depth distributions of enzyme activity and bulk organic matter content were determined in sediments of Aransas Bay and Copano Bay Texas, to investigate enzyme dynamics as related to the geochemical properties of the sediment. Vertical profiles of activity in sediment showed that the enzymes were more active at the surface and that the potential hydrolysis rate of leucine aminopeptidase was higher than that of [beta]-glucosidase. Vertical patterns of enzyme activity correlated (weakly) with variations in sediment organic matter (TOC, TN, and carbohydrates) content. Enrichments of sediment samples with monomeric organic compounds and inorganic nutrients did not affect leucine aminopeptidase and [beta]-glucosidase activities in short- and long-term incubations. Enzyme activity was independent of nutrient availability and suggested that microbial communities were not nutrient-limited. Time-course assays of bacterial hydrolysis of TOC, TN, and carbohydrates provided information about how substrate limitation may affect enzyme activity. Positive correlations between bulk TOC and TN content and enzyme activity indicated enzyme dependence on polymeric substrate content. Induction of enzyme activity after sediment enrichments with specific labile compounds confirmed the importance of available organic substrate to enzyme hydrolysis efficiency. A kinetic approach established the occurrence of enzyme inhibition and its effects on enzyme hydrolytic capacity. The addition of a specific-enzyme substrate to sediment samples modified enzyme parameters and indicated that a substrate-reversible type of inhibitor could reduce enzyme hydrolytic capacity. The addition of polyphenol, as a natural inhibitor of enzyme activity, to the sediment resulted in a concomitant reduction of leucine aminopeptidase activity and ammonium regeneration rate, and thus demonstrated a close coupling between enzyme activity and sediment ammonium regeneration. These research results demonstrate the dynamic nature of the hydrolytic enzymes, provide information about the mechanisms of induction and inhibition of activity, and demonstrate some implications of reducing the hydrolytic capacity to organic matter decomposition and nutrient regeneration rates. / text
259

Toxicokinetics and Bioaccumulation of Polycyclic Aromatic Compounds in Wood Frog Tadpoles (Lithobates sylvaticus) Exposed to Athabasca Oil Sands Sediment

Bilodeau, Julie January 2017 (has links)
Many polycyclic aromatic compounds (PACs) are toxic, carcinogenic, and mutagenic. As a result, their effects on aquatic biota and ecosystems are of great concern. Research on PACs in aquatic biota often overlooks the role of amphibians, alkylated PACs, and sediment as an uptake route. In order to study the accumulation and toxicokinetics of PACs following sediment and aqueous exposure, and to compare the bioaccumulation potentials of parent and alkyl PACs, two accumulation-elimination experiments using wood frog tadpoles (Lithobates sylvaticus) of Gosner stage 28-32 were conducted (one evaluating exposure to contaminated sediment and water, and the other to contaminated water alone). A complementary field study was then conducted near Fort McMurray, Alberta to assess PAC body burdens in field-collected amphibian larvae, and to determine whether PAC body burdens are related to exposure to sediment and/or water in the field. The results of our studies showed that PAC concentrations and uptake rates in wood frog tadpoles were highest when they were exposed to PAC-contaminated sediment. Consequently, we determined that the dominant route of exposure of wood frog tadpoles to PACs is sediment rather than water. This finding supports other studies that have shown dietary uptake to be an important route of PAC exposure in other aquatic organisms. In both the laboratory and field study, alkyl PAC concentrations exceeded those of parent PACs in wood frog tadpoles, which also demonstrated petrogenic PAC profiles. Interestingly, parent PACs seemed to have greater bioaccumulation potential than alkyl PACs in the laboratory-exposed wood frog tadpoles (in relation to sediment), possibly due to greater bioavailability or lower metabolism of parent PACs or alternatively, due to a saturation in uptake of alkyl PACs. Nevertheless, only a few compounds, including anthracene, fluoranthene, retene, and C1-benzofluoranthenes/benzopyrenes, were found to have higher bioaccumulation potentials. Lithobates sylvaticus tadpoles seemed to be efficient at eliminating and metabolizing both parent and alkyl PACs. However, the elimination of some compounds, such as C4-naphthalenes, was not as efficient. Furthermore, C3-fluorenes and C2-dibenzothiophenes were isolated as potential markers of amphibian larvae exposure to PAC-contaminated sediment due to their positive correlation with the wetland sediment concentrations. Additional field collections in the Athabasca oil sands are warranted to verify the utility of these markers in the natural environment. Evidently, this thesis highlights the importance of including sediment exposure and alkylated PACs in toxicological and field studies of benthic and epibenthic organisms. The results of this study are the largest, most comprehensive set of toxicokinetic and bioaccumulation information of PACs (52 analytes) in the amphibian larvae Lithobates sylvaticus obtained to date.
260

Determination of Heterogeneity by High-Resolution Seismic Reservoir Characterization in the Heavy Oil Temblor Reservoir of Coalinga Field, California

Mahapatra, Sailendra Nath 12 December 2005 (has links)
The research focuses on analysis and subsurface imaging of siliciclastics rocks on steam-affected 3D poststack seismic data, merged from different vintages, from the Temblor Formation in the Coalinga heavy oil reservoir in the San Joaquin basin, California. The objective was identification, delineation, and demarcation of reservoir heterogeneities by seismostratigraphic and seismogeomorphic analysis. The proximity of the San Andreas Transforms greatly controlled basin evolution and caused substantial reservoir heterogeneity by changing the depositional environment from shallow marine to near-shore fluvial. Moreover, two unconformities dissect the reservoir interval. The seismic dataset exhibits erratic, distorted reflection strengths and amplitudes caused by steam-injection-aided production. A petrophysical analysis based on Gassmann fluid substitution suggests a 27% P-wave velocity decrease in steam-saturated intervals. Seismic to well log ties were problematic and vexing due to the resulting statics, wavelet changes, and line mismatches. Mapping and flattening on a deeper horizon, however, allowed mapping of the internal unconformities and well ties which were crucial for seismostratigraphic sequence identification. Visualization of seismic attributes brought out stratification patterns and two distinct, laterally and vertically extensive, porous, and interconnected facies tracts interpreted as incised valley fills and tidal-to-subtidal deposits as evidenced by bright, steam related amplitudes. Seismic attribute analysis, Geobody Visualization and Interpretation, and structure and isochron maps brought out two prominent channel-systems, recut and restacked in the central part of the area. These deposits were identified on seismic data and correlated to high-gamma coarsening-upward sands on logs and cores. The deeper one, shifting towards SSE with depth, lies between the Base Temblor and Buttonbed unconformities both in the southwestern and northwestern parts of the study area and is scattered in the western-central portion. The shallower one originates in southwestern corner below the Top Temblor unconformity shifts towards ESE-SE with depth, and runs nearly parallel to the Top Temblor unconformity. It cuts across the Valv unconformity in central part creating a channel incision, and follows the Buttonbed unconformity towards the north. The investigation segmented the reservoir into channels, non-channel bearing, and unconformity-bounded subunits which will allow the operator to improve steam injection and optimize placement of oil producing infill wells. / Ph. D.

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