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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.
281

Kinematic History of the Northwestern Argentine Thrust Belt and Late Cretaceous Tectonic Underplating Beneath the Canadian Cordillera

Pearson, David Malcolm January 2012 (has links)
The American Cordillera, a major mountain belt spanning>15000 km along the western margins of North and South America, formed as a result of crustal shortening and magmatism during ocean-continent convergence. These mountains were the loci of addition and redistribution of continental crust. The contributions presented here address the style, timing, and kinematics of underthrusting of continental crust in the retroarc of the central Andes as well as the rapid burial and metamorphism of forearc rocks that contributed to magmatism in the Canadian Cordillera. This work involved geological mapping and structural analysis coupled with geo- and thermochronological analysis. In the central Andes, results confirm a southward transition in structural style and magnitude of Cenozoic shortening that coincides with the disappearance of a thick Paleozoic basin that accommodated major Cenozoic shortening. U-Pb and (U-Th)/He results also demonstrate that thrust belt kinematics in northwestern Argentina were greatly influenced by pre-orogenic heterogeneities in Cretaceous rift architecture. Results from western Canada reveal that rapid underthrusting of forearc rocks occurred during Late Cretaceous time, likely associated with an episode of shallow subduction. This event did not result in basement-involved foreland uplifts thought to be a signature of shallow subduction in the western United States and central Argentina. Taken together, this work has the major implication that variations in the pre-orogenic upper crustal architecture strongly influence the behavior of the continental lithosphere during orogenesis, a result that challenges geodynamic models that largely neglect upper plate heterogeneities.
282

Mackenzie River Delta Chronology

Giddings, J. L., Jr. 04 1900 (has links)
No description available.
283

Santa Fe Ski Basin Proposed Expansion Ethnographic Assessment

Evans, Michael, Stoffle, Richard W., Krause, Elizabeth 01 June 1993 (has links)
The purpose of this research study was to conduct an ethnographic assessment for an Environmental Impact Statement (EIS) of a proposed expansion plan for the Santa Fe Ski Area located in the Sangre de Cristo Mountains north of Santa Fe, New Mexico. Along with expansion into forest areas outside the existing Special Use permit boundaries, the proposed plan includes new buildings, parking lots, lifts, ski runs, and snowmaking within the existing ski area boundary. The ethnographic assessment concentrates on those cultural resources known to be in the area, as identified by Pueblo participants in the research study. This project had three objectives: a) what impact would the project have on the traditional uses, cultural uses, values, and belief practices of Tesuque Pueblo and other Pueblos' uses of the area; b) how would the ski area expansion affect the traditional use area of the Tesuque Pueblo and other Pueblos; and c) what specific areas of traditional cultural use, including those of Hispanic origin, would be affected by the proposed alternatives.
284

THE RELATIONSHIP BETWEEN LITHOLOGY AND SLOPE FORM IN THE TUCSON MOUNTAINS, PIMA COUNTY, ARIZONA

Khanchoul, Kamel, 1959- January 1987 (has links)
The relationship between lithology and slope morphology is investigated at eight sites on granitic, andesitic, and sedimentary rock slopes in the Tucson Mountains. Several methods are used in the study. Topographic profiles are constructed. Skewness indices of the slope shapes, maximum and minimum slope angles, and slope lengths of the different slope profiles are computed and compared with each other. Debris size analysis is done to better determine hillfront/piedmont junctions. Slope surface regularities of the three lithological slopes are analysed and compared. The results show that the granitic piedmont slopes are found to be slightly concave to almost rectilinear, indicating their high resistance to erosive processes. In contrast, the concavity of the andesitic and sedimentary piedmont slopes demonstrate their inability to resist the erosive attack on them. However, in the case of the hillfront slopes, slope forms do not reflect lithological variations.
285

Mountain sheep habitat characteristics in the Pusch Ridge Wilderness, Arizona

Etchberger, Richard Carl, 1957- January 1988 (has links)
Mountain sheep (Ovis canadensis mexicana) in the Pusch Ridge Wilderness (PRW), Santa Catalina Mountains, Arizona have abandoned historic habitat and now occupy 44 km². I used univariate analyses to quantify differences of physiographic and vegetational variables between abandoned habitat and habitat that is still used by mountain sheep. A discriminant function model characterized the magnitude of the differences between the 2 habitats. Habitat that supports mountain sheep has less human disturbance and is more open with more side oats grama (Bouteloua curtipendula), red brome (Bromus rubens), brittle bush (Encelia farinosa), and forb cover, but less ground cover, bush muhly (Muhlenbergia porteri), and turpentine bush (Haplopappus laricifolius) than habitat that was abandoned by mountain sheep. Fire is important in still used habitat because it reduces tall plants that obstruct mountain sheep vision. Human disturbances should be minimized in mountain sheep habitat.
286

Desert bighorn sheep and nutritional carrying capacity in Pusch Ridge Wilderness, Arizona

Mazaika, Rosemary, 1964- January 1989 (has links)
The number of desert bighorn sheep (Ovis canadensis mexicana) in Pusch Ridge Wilderness (PRW), Santa Catalina Mountains, Arizona has declined to between 50 and 100 animals. Sheep have restricted movements to the southwest corner of PRW. I developed a model based on nitrogen (N) content of forage and forage quantity to measure seasonal changes in nutritional carrying capacity of sheep use areas in PRW. Forage based estimates of animals numbers were greater for April to September than for October to March. My study suggests that forage is not limiting desert bighorn sheep in PRW and illustrates the potential to support more desert bighorn sheep in PRW than the current population. Seasonal fluctuations in range productivity should be examined in relation to human disturbances proximal to desert bighorn sheep habitat and fire management programs for PRW.
287

First year effects of thinning coppice on Quercus emoryi in southeastern Arizona

Bennett, Duane Anthony, 1956- January 1990 (has links)
This study was conducted to measure the effects of thinning coppice on Emory oak (Quercus emoryi). Thinning treatments were applied to sprouts of different ages. Height and diameter measurements were taken immediately after thinning and again one year later. Sprouts were classified into 5 age groups, 4 stump diameter groups, and 4 residual sprout groups. The interactions of these treatments and their effect on volume growth were analyzed. The results showed volume growth per stump was directly related to the number of sprouts per stump; volume growth per sprout was inversely related to the number of sprouts per stump; volume growth per stump and per sprout were both significantly affected by the age of the sprout at the time of thinning; and that stump diameter size had no significant effect on volume growth.
288

Holocene glacial history of the Bowser River Watershed, Northern Coast Mountains, British Columbia

St-Hilaire, Vikki Maria 24 December 2014 (has links)
Accelerated glacial recession and downwasting of glaciers in the Bowser River Watershed of the northern British Columbia Coast Mountains have exposed subfossil wood remains and laterally contiguous wood mat layers. To develop an understanding of Holocene glacial fluctuations in this region, field investigations were conducted in 2005, 2006 and 2013 at Frank Mackie, Charlie, Salmon and Canoe glaciers. These wood remains represent periods of Holocene glacier advance, when glaciers expanded and overwhelmed downvalley forests. Dendroglaciology and radiocarbon analyses revealed five intervals of glacial expansion: (1) a mid-Holocene advance at 5.7-5.1 ka cal. yr BP; (2) an early Tiedemann advance at 3.6-3.4 ka cal. yr BP; (3) a late Tiedemann advance at 2.7-2.4 ka cal. yr BP; (4) a First Millennium AD Advance at 1.8-1.6 ka cal. yr BP; and, (5) three advances during the Little Ice Age at 0.9-0.7, 0.5 and 0.2-0.1 ka cal. yr BP. These results provide new evidence for mid-Holocene glacier activity in northern British Columbia, as well as supporting previous research that Holocene glacier advances were episodic and regionally synchronous. / Graduate / 0368
289

Styles of deformation in windows and slide blocks of the Roberts Mountains thrust belt, central Nevada

Reynolds, Stephen J., Reynolds, Stephen J. January 1977 (has links)
No description available.
290

Enhancing Workforce Development in Rural Communities: The Georgia Mountains Manufacturing Initiative

Kaup, Jason 13 May 2016 (has links)
This study examined the perceptions of stakeholders in the Georgia Mountains Manufacturing (GMM) region in terms of how the education providers, high schools, and technical colleges worked together to address pathways, skills-gap training, and increase human capital for the benefit of both industry and the communities in the region. The GMM initiative was funded in 2010 with a two-year grant through the Governor’s Office of Workforce Development (GOWD) under former Governor Sonny Purdue. The purpose was to address graduation rates, employment readiness, and specific training needs of manufacturing industries in the region. That initiative was designed to create a Georgia Work Ready Region that provided targeted training for advanced manufacturing jobs within one state sector. This dissertation research examined the public-private partnerships to provide a better understanding of the education and economic development factors in the region. The researcher used semi-structured interviews to examine stakeholder perceptions of the relationships found between business and industry, government and local education providers in the six-county area. Twelve members participated in semi-structured interviews about the delivery of career and technical education (CTE) programs in the designated work-ready region. The researcher identified the employability traits that educators and employers desire for success in middle-skill manufacturing jobs. Although education and economic development partnerships were stimulated by the demonstration project they could not sustain long term viability in the region. Additionally, the CTE delivery system lacked the flexibility to design new school-to-work transitions for the sector.

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