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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.
61

Stratigraphy, Geochronology, and Tectonics of the Salt Lake Formation (Tertiary) of Southern Cache Valley, Utah

Smith, Kristine A 01 May 1997 (has links)
This study synthesizes the deposition and tectonic evolution of the Tertiary deposits in southern Cache Valley, a narrow, north-trending valley in the northeastern Basin-and- Range Province. The surrounding mountains consist of Proterozoic and Paleozoic sedimentary rocks. Southern Cache Valley is an east-tilted half-graben. The oldest Tertiary sediments are on the west side of the basin, and the overall dip is to the east. The Late Miocene to Early Pliocene Salt Lake Formation (Tsl) accumulated above the thin (to absent) Early to Middle Eocene Wasatch Formation (Tw) and the newly identified Fowkes and Norwood Tuff equivalents (Tfn; late Middle Eocene to Middle Oligocene). The two post-Wasatch units consist of felsic tuff, tuffaceous sandstone, pebble to boulder conglomerate, limestone, and sandstone. Pebble counts, generalized measured sections, and detailed mapping permitted subdivision of the Tertiary deposits into mappable subunits. Numerous faults and N-trending folds are present in Tertiary deposits in the SW part of the area. The Cenozoic-Paleozoic contact is offset by normal faults. The faults with ENE trends offset both the Paleozoic and Tertiary rocks, and thus are younger than 5 .1 Ma. Thick gravels, rich in Paleozoic carbonates, dominate exposures in the east, near the East Cache fault zone. Few cobbles are present within the Tfn except near the base, whereas conglomerates rich in clasts of Paleozoic carbonates are intertongued with tuffaceous sediments throughout the Tsl, especially eastward. Up to 8,000 feet (3439 m) of the Tsl accumulated as the narrow Cache Valley basin formed during the Neogene by rapid eastward downfaulting.
62

Factors Affecting the Toxic Cyanobacteria Nodularia Spumigena in Farmington Bay of Great Salt Lake, Utah

McCulley, B. Eric 01 May 2014 (has links)
Farmington Bay of Great Salt Lake receives a significant amount of the nutrient-polluted runoff from Salt Lake and Davis Counties, Utah. This nutrient-laden runoff has led to seasonal blooms of blue-green algae, Nodularia spumigena, which produce a toxin called nodularin that has been shown to be toxic to aquatic organisms, birds, and mammals. Nodularia spumigena are the most common algae found in Farmington Bay. This study focused on understanding the physical and chemical factors controlling the growth of Nodularia spumigena in order to improve our knowledge about how nutrients impact algae in the Great Salt Lake. The salinity of the bay ranged from almost fresh water (less than 0.2%) to water twice as salty as the sea (7.0%). Nutrient (nitrogen and phosphorus) levels were high in the bay, and showed patterns of change from south to north. Nodularia spumigena was found in concentrations that greatly exceeded the World Health Organization’s standards for contact recreation. Laboratory studies suggest that nutrients and salinity are significantly correlated with levels of Nodularia spumigena from Farmington Bay. In combination with complex ecosystem interactions, nutrients and salinity in Farmington Bay apparently contribute to the high levels of Nodularia spumigena that we measured.
63

Effects of Heavy Metals (Cadmium, Copper, and Mercury) on Reproduction, Growth, and Survival of Brine Shrimp (Artemia salina) from the Great Salt Lake

Gebhardt, Karl A. 01 May 1976 (has links)
The purpose of this paper is to report findings concerning the effects of cadmium , copper, and mercury on the brine shrimp Artemia Salina, of the Great Salt Lake. Metal toxicity was observed in relation to acute susceptibility, growth, reproduction, and hatching of the brine shrimp. Heavy metal concentrations such as cadmium, copper, and mercury are known to be considerably higher in the Great Salt Lake than those in both freshwater and seawater. No published study has been concerned with heavy metal effects on organisms in salinities greater than seawater (35 grams per liter total dissolved solids). The experiments reported in this paper were carried out in salinities approximating the Great Salt Lake (150-320 grams per liter total dissolved solids). Results of this study indicate that cadmium, copper, and mercury toxicities to the brine shrimp may not be comparable at varying salinities. Findings of acute toxicity experiments were compared to other heavy metal studies on marine organisms. The brine shrimp was found to be very resistant to cadmium and copper poisoning and moderately resistant to mercury. Neither cadmium nor copper inhibited hatching of the brine shrimp eggs although mercury caused severe inhibition at concentrations of 0.3 milligrams per liter. Only cadmium at concentrations between 1.0 and 33 milligrams per liter significantly suppressed growth rate and reproduction. Mercury and copper were not found to affect growth and reproduction below concentrations causing acute poisoning. Mercury was found to be the most lethal to the adult brine shrimp with a range of times to 50 percent mortality from 126 to 8.5 hours at mercury concentrations of 0.01 to 100 milligrams per liter respectively. Copper caused mortalities at concentrations of 1 to 67 milligrams per liter with respective times to 50 percent mortality of 124 and 12 hours. Copper was shown to precipitate out at concentrations near 12 milligrams per liter, Cadmium was found to be the least lethal with a range of times to 50 percent mortality from 94 to 320 hours with respective cadmium concentrations of 100 and 3.3 milligrams per liter.
64

An analysis of consumer preferences for peaches in Salt Lake City, Utah, 1947

Larsen, Marion R. 01 May 1948 (has links)
Peaches are the predominant tree fruit in Utah. Preliminary estimates for 1947 indicate a crop of 933,000 bushels valued at $1,679,000, which represents approximately 27 percent of the value of the major fruits grown in Utah and 1.2 percent of the value of all agricultural commodities grown in the state (5:23). It should be noted, however, that the 1947 peach crop was somewhat above normal. The estimated average annual production over the 10-year period 1938 to 1947 was 722,000 bushels.
65

Characterization of Selected Bacteria from the North Arm of the Great Salt Lake

Crane, John L. 01 May 1974 (has links)
Thirteen bacterial cultures were isolated from the North arm of Great Salt Lake during the months of January and February of 1973. Eleven isolates were gram-negative pleomorphic rods which lysed in hypotonic solution. The remaining two were gram-positive cocci. All isolates and one known strain of Halobacterium salinarium were subjected to examination of morphological, cultural, physiological, and biochemical characteristics. A numerical taxonomic analysis was applied to the compiled characters to compute a coefficient of similarity for each individual isolate as compared to all other isolates. A comparative analysis was included in the similarity computation using characters assembled from those reported in the literature for six taxonomically accepted species of halophilic bacteria. The lake isolates proved to be extreme halophiles with relative high levels of similarity between each other and the known bacteria included in the numerical analysis.
66

Relationship Between Opinions Toward Flouridation andSocioeconomic Status of Salt Lake City Residents

Kunz, Craig D. 01 May 1974 (has links)
The purpose of the study was to determine if a relationship exists among opinions toward fluoridation of public water supplies, income, and level of education of the people of Salt Lake City, Utah. There were also two secondary concerns. One was to determine if a relationship exists between opinions toward fluoridation and other controversial social issues. The issues identified for investigations were: (1) the Supreme Court decision on abortion, (2) the Equal Rights Amendment, and (3) capital punishment. The second was to determine the factors on which opinions regarding fluoridation were based. The results of the data that was collected indicated that the higher the education level of the population the higher the probability of a favorable opinion about fluoridation. The lower the education level of the population the higher the probability of an opinion of opposition to fluoridation. (2) If the subjects yearly income was $20,000 or more there was an increased likelihood of a favorable opinion of fluoridation. If the subjects yearly income was less than $20,000, there was a greater likelihood that the opinions would be in opposition to fluoridation. (3) A majority of the subjects opposed the Supreme Court ruling on abortion and the Equal Rights Amendment. A majority favored reinstatement of capital punishment. Interpreted, this was felt to reveal a tendency of the subjects to adopt a conservative stand on controversial social issues.
67

Winter Waterbird Ecology on the Great Salt Lake, Utah, and Interactions with Commercial Harvest of Brine Shrimp Cysts

Roberts, Anthony J. 01 December 2013 (has links)
Interactions among commercial fisheries and birds have been studied in open ocean ecosystems and at aquaculture facilities. On the Great Salt Lake (GSL), Utah, USA, a commercial harvest of brine shrimp (Artemia franciscana) eggs (i.e. cysts) occurs annually during fall and winter. Coinciding with commercial harvest is the use of the GSL by millions of waterbirds which has the potential to result in conflict among industry and birds. The objectives of my research were to examine fall and winter ecology of birds using the GSL and interactions with the brine shrimp cyst harvest. I examined the influence of temperature and food availability on the number and distribution of waterfowl and eared grebes (Podiceps nigricollis). I also assessed the diets of the same species to see how much cyst biomass is being consumed by birds compared to removal by commercial harvest. A mass die-off (i.e. downing) of migrating eared grebes occurred during my research, so I assessed differences among birds that died and those that did not to better explain this phenomenon. Finally, I assessed the breeding origin of northern shovelers (Anas clypeata) wintering on the GSL using stable isotopeand banding data.I found that commercial harvest boats did not influence duck population numbersor distribution; rather temperature and food availability most influenced abundance and distribution, though this influence varied by species. Compared to commercial harvest, northern shovelers, green-winged teal (Anas crecca), and eared grebes removed a small fraction of the total amount of cysts that were removed from the GSL. Waterfowl diets were mainly wetland plant seeds during fall and spring, but when freshwater marshes were frozen in winter, ducks ate mostly brine shrimp cysts and brine fly (Ephydra spp.) larvae. Eared grebes are highly associated with saltwater habitats and they consumed adult brine shrimp most of the fall. Eared grebes that perished during the downing had mercury and selenium concentrations above levels seen in pre- and post-downing birds and higher than observed concentration that impact bird species, providing a potential ultimate cause of death during snowstorms that accompany most downings. Stable isotope analysis indicated northern shovelers that winter on the GSL had breeding origins throughout the specie’s range, but most came from local or southern Prairie Pothole Region breeding populations.
68

A Study of the Effectiveness of Tune-ups in Controlling Vehicle Emissions in Salt Lake County

McIntosh, Howard B. 01 May 1972 (has links)
The Federal Government has placed stringent standards on the manufacturers of automobiles to control vehicle emissions. Few states standards have been set for used vehicles to insure the vehicle continues to meet this standard. Studies have shown that vehicles that are properly tuned are emitting less harmful pollutants from the exhaust. Additional studies are needed to determine if cars are being adequately turned to meet exhaust emissions. The study showed 93 per cent of the new 1971 model cars were not meeting the standard established by the Environmental Protection Agency. Eighty-seven per cent of the 1970 model cars and 83 per cent of the used 1971 model cars tested would not meet the same standards. There was a very low correlation between emission level and the mileage driven since the vehicle was tuned indicating a need for more emphasis on tune-ups and maintenance of automobiles to meet emission standards.
69

A Comprehensive Study Evaluating Driver Education in the Senior High Schools from Analyses of Driving Records of Salt Lake City High School Students

Bushman, H. Keith 01 May 1954 (has links)
Officials responsible for the control and administration of the traffic on the highways and streets of the nation are aware that good roads, markings, signals, and equipment are necessary. They also realize that the human element involved in the process of operating a vehicle is of the utmost importance. Highways can only be termed good to the extent of the actions of the drivers who use these roads. Studies have been made throughout the nation in different states and cities to determine the results of formal training of drivers. The results of these studies answer many questions and also leave many questions unanswered. A previous study by H. Neil Anderson, in 1952, of the city high schools here in Utah gave some indication of the validity of the hypothesis that students who successfully coplete the driver education course have better performace records than those who did not take the course. Anderson's study, and others in the nation, leaves a challenge to carry out a survey over a longer period of actual driving time for the participants in the Salt Lake City high schools. The purpose of this thesis is to make a comprehensive study of driving records of Salt Lake City high school students who have received training in the driver education program, and those of students who have received no such training. The main objective of this study is to compare the driving records in terms of violations and accidents of the trained drivers against the violations and accidents records of the untrained drivers. This is a comprehensive study evaluating driver education in the senior high schools from analyses of driving records of Salt Lake City high school students.
70

Pushing the Car of Progress Forward: The Salt Lake Tribune's Quest to Change Utah for Statehood, 1871-1896

Mills, Robert Patrick 01 May 2007 (has links)
The debate over Utah statehood involved several controversial issues that the United States government and the American public wanted resolved before admission would be granted. One strong advocate for such changes in Utah was the widely published newspaper, the Salt Lake Tribune, which continually published anti-statehood and anti-Mormon ideas in the final decades before Utah was finally admitted in 1896. This thesis studies and analyzes the Tribune’s editorials and news stories to better understand which issues opponents of statehood worried the most over and what they wanted to accomplish with their protest. It finds that Mormon political domination was the paper’s central concern throughout the last decade of the debate, even after developments showed change on the horizon. This thesis also examines the Tribune’s ability to reach Utah readers and a national audience through its connections with the Associated Press. By citing numerous newspapers from throughout the United States and members of Congress who were close to the statehood debate, this thesis shows that the Tribune got its message out and that it played a strong part in the statehood struggle.

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