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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.
51

Foliar morphology and physiology of Sequoia sempervirens /

Mullin, Lucy Penn. January 1900 (has links)
Thesis (M.A.)--Humboldt State University, 2008. / Includes bibliographical references (leaves 40-47). Also available via Humboldt Digital Scholar.
52

Assessing natural and human alterations to coastal sediment supply in California and the impacts on regional beach sustainability

Willis, Cope M. January 2002 (has links)
Thesis (Ph. D.)--University of California, Santa Cruz, 2002. / Typescript. Includes bibliographical references (leaves 126-133).
53

Episodic transport of sediment in the nearshore

Jaffe, Bruce Evan. January 1900 (has links)
Thesis (Ph. D.)--University of California, Santa Cruz, 1993. / Typescript. Includes bibliographical references (leaves 162-172).
54

Quantitative shoreline change assessment and identification of erosion hotspots in Santa Cruz County, California

Moore, Laura Jean. January 1998 (has links)
Thesis (Ph. D.)--University of California, Santa Cruz, 1998. / Typescript. Includes bibliographical references.
55

Elevated atmospheric carbon dioxide and chronic atmospheric nitrogen deposition change nitrogen dynamics associated with two Mediterranean climate evergreen oaks /

Cario, Cara Hinkson. January 2005 (has links)
Thesis (Ph. D.)--University of California, Davis and San Diego State University, 2005. / Includes bibliographical references. Also available via the World Wide Web. (Restricted to UC campuses)
56

Hazard sensitivity in Newfoundland coastal communities : impacts and adaptations to climate change, a case study of Conception Bay South and Holyrood, Newfoundland /

Paone, Laura Clare, January 2003 (has links)
Thesis (M.Sc.)--Memorial University of Newfoundland, 2003. / Bibliography: leaves 153-170. Also available online.
57

Compréhension des dynamiques morpho-sédimentaires cohésives et non- cohésives des littoraux de Bretagne Sud (France) à différentes échelles spatio- temporelles. / Abstract : Understanding the morpho-sedimentary dynamics of cohesive and non- cohesive beaches in the South-Brittany region (France) at different spatiotemporal scales.

Morio, Olivier 20 December 2017 (has links)
À l'échelle du monde, les littoraux peuvent se diviser en différentes catégories : les côtes rocheuses, sableuses, vaseuses et mixtes. Cependant, les littoraux meubles sableux et vaseux sont retrouvés régulièrement mélangés sur différentes façades côtières mondiales. Des apports de vases temporaires ou permanents sont en effet observés sur des plages sableuses. Ces environnements mixtes atypiques, qui couplent alors les processus d’érosions, de transports et de dépôts associés à la fois aux sédiments cohésifs et non cohésifs, ont été peu étudiés. Afin d’identifier les forçages des variations morpho-dynamiques sur des environnements sableux et mixtes, quatre plages sablo-vaseuses ou entièrement sableuses de type Low-Tide-Terrace ont été suivies mensuellement sur deux années en baie et estuaire de la Vilaine (Bretagne Sud). Des suivis hydro-morpho-sédimentaires spécifiques à haute résolution et des suivis par photogrammétrie ont été menés ponctuellement sur ces sites. À l'échelle régionale, ce travail met en évidence le rôle de la morphologie initiale et l’héritage géologique régional dans la réponse morphologique du littoral de la baie de Vilaine aux conditions d’énergie extrêmes. La capacité de résilience à moyen-terme du littoral des plages de Bretagne Sud a été démontrée. Dans une approche plus spécifique, un comportement morphodynamique d'une plage sablo-vaseuse proche de celle d'une plage uniquement sableuse a été observé lors des phases de haute énergie. Les variations d’altitudes du platier vaseux et des modelés sédimentaires en ridges and runnels sont principalement contrôlées par l’énergie des vagues mais également par les propriétés physiques des sédiments et particulièrement celles liées à l'interaction entre le sable provenant de la section réflective et la vase de la section dissipative. La capacité d’érosion du platier vaseux par les vagues est potentiellement diminuée au niveau des interfaces des sédiments cohésifs et non-cohésifs. / At the world scale, coastal areas can be divided in several categories: rocky, sandy, muddy and mixed coasts. However, these sedimentary coasts are regularly found mixed. Temporary or permanent mud inputs are observed on the sandy beaches. These atypical mixed environments, coupling erosional, transports and deposits processes associated to cohesive and non-cohesive sediments have been poorly studied. So, understanding theirs morphological and sedimentary dynamics and the identification of regional and local forcings driving them are essential. Four sandy-muddy or fully sandy Low-Tide-Terrace beaches from the bay and estuary of Vilaine (South-Brittany) have been monthly monitored over two years to characterize their morphodynamics beahaviors. Specific monitoring of coupled hydrodynamics and morpho- sedimentary surveys and photogrammetry experiments have been conducted on mixed sandy- muddy or full sandy beaches. At a regional scale, this work highlights the role of the initial morphology and regional geology inheritance on the morphological response of the littoral zones to extreme energy conditions. Despite some erosion patterns in local parts of beaches, particularly close to shore protection structures, the mid-term recovery capacity of the south-Brittany coastal area after extreme wave energy conditions have been proved. In a more specific approach, the works regarding the sandy- muddy beach dynamic show a morphodynamics behaviour close to that of a fully sandy beach during high energy event. The mudflat elevation changes and the dynamic of the ridges and runnels sedimentary patterns are mainly controlled by the incoming waves but also by the own physical properties of the sediment, particularly those induced by the interaction between the sand from the reflective section and the mudflat. A sand deposit between mud layers potentially decreases the wave erosion capacity on the mudflat.
58

A geological reconnaissance of Bowie Seamout

Herzer, Richard Howard January 1970 (has links)
Bowie Seamount, a submerged volcano situated off the west coast of Canada at 53° 18; N, 135° 39' W, has a relief of 10,000 ft. and comes to within 100 ft. of the ocean surface. It is made up of a series of intersecting ridges which together give the mountain an overall northeast - southwest elongation. It appears to be a combination central and fissure type volcano which has been built up over a system of intersecting fractures in the oceanic crust. Two terraces form the flattened summit of the volcano at approximate depths of 45 and 130 fathoms. These are thought to be the remains of platforms produced by combined wave erosion and shallow-water vulcanism during late Quaternary time when sea level was lower than it is today. The last phase of volcanic activity on the summit occurred after the formation of the upper terrace no more than 18,000 years ago. Samples dredged from the upper half of the volcano include: pillow fragments, fragments of non-pillowed flows, pillow breccias, bombs, tuffs, ash, and unsorted tephra. The rocks are mainly alkali olivine basalts, accompanied by rare andesites which, presumably, were derived by differentiation of the basaltic magma. Feldspathic and gabbroic inclusions, many of which appear to be cumulates, are common in the basalt. Ice-rafted rocks are rare on the summit of Bowie Seampunt but are common on its nearest neighbour - Hodgkins Seamount. A ferro-manganese deposit, apparently over 1 million years old, that exists on the summit of Hodgkins Seamount, suggests that this peak is relatively much older than the summit area of Bowie Seamount. Palagonite appears to form as the initial phase of weathering of glassy basalts in the area of study but the products of more advanced weathering are montraorillonite and zeolites. Rock fragments that have been rounded by chemical weathering are common. / Science, Faculty of / Earth, Ocean and Atmospheric Sciences, Department of / Graduate
59

Canada Customs, Each-you-eyh-ul Siem (?) : sights/sites of meaning in Musqueam weaving

Fairchild, Alexa Suzanne 11 1900 (has links)
This thesis focuses on the production and display of weavings made by a small number of Musqueam women, who in the 1980s began weaving in the tradition of their ancestors. It addresses the way in which these weavings, positioned throughout Vancouver and worn in public settings, build a visual presence to counter the exclusion of Coast Salish cultural representations from the public construction of history in Vancouver and the discourse of Northwest Coast art. The Vancouver International Airport and the Museum of Anthropology at the University o f British Columbia both share with Musqueam a history of place. A distinct relationship fostered between Museum staff and members of the Musqueam community has yielded several exhibits since the first, Hands of Our Ancestors: The Revival of Weaving at Musqueam, opened in 1986. The presence of Musqueam material at the Museum is part of an extensive history of interaction and negotiation between Canadian museums and the cultural communities whose histories, traditions and material culture are represented - a history which encompasses issues of representation, authorship and authority. The Vancouver International Airport is also situated on Musqueam traditional territory. Designed by representatives from the Musqueam Cultural Committee and the Airport project team, the international arrivals area features works of contemporary Musqueam artists which are intended to create a sense of place with an emphasis on the distinctiveness of its location. Travelers cross several thresholds in the terminal - the sequence o f these crossings carefully choreographed so that deplaning passengers pass from the non-space of international transience to a culturally specific space marked by Musqueam's cultural representations, and then past Customs into Canada. Certain incidents at these sites indicate that visibility and self-representation do not in themselves answer the problems of power and history. When the Museum of Anthropology hosted a meeting for leaders of the Asia Pacific Economic Community in 1997, a newly implemented protocol agreement between Musqueam and the Museum was broken; and in a number of instances, achievements at the Airport have also been impaired. Despite these limits, weavings are not examples of token native inclusion as some critics argue. Rather, they are cultural representations strategically deployed by the Musqueam community. Enlarged from traditional blankets to monumental hangings, these weavings participate with other more recognized monumental Northwest Coast forms. They are visual, public signifiers of Musqueam identity which, without violating boundaries between public and private knowledge, carry messages from the community to a broader audience - messages intended to mark Musqueam's precedence in Vancouver's past as well as to claim visibility in the present. / Arts, Faculty of / Art History, Visual Art and Theory, Department of / Graduate
60

Geology and geochronometry of the coast plutonic complex adjacent to Douglas, Sue and Loretta channels, British Columbia

Runkle, Dita Elisabeth January 1979 (has links)
Five major units were mapped in shoreline exposures of the Coast Plutonic Complex adjacent to Douglas, Sue and Loretta Channels: 1) paragneiss and migmatite of the Central Gneiss Complex, 2) quartz-biotite schist, amphibolite, quartzite,and marble of the Metasedimentary Rocks, 3) quartz diorite and quartz monzonite of the Kitkiata pluton, 4) granodiorite of the Quottoon pluton and 5) Agmatite, composed of early xenoliths of banded metamorphic rock, middle stage intrusions of granitic rock, and late pegmatite, aplite and lamprophyre dikes. Pressure estimates of 7 ± 1 kb for this part of the Coast Mountains are arrived at from the stable assemblages in a kyanite-staurolite schist, and by comparison with pressures published for areas along strike to the north. Amphibolites provide a low temperature estimate o f 550°C. Calcsilicate assemblages place the high temperature limit of metamorphism between 560 and 660°C at 5 kb. Elevated pressures would increase temperature somewhat. The area is structurally characterized by a well developed, steeply dipping foliation that strikes northwest, widespread isoclinal folds with axial plane foliation parallel to regional foliation, and a moderate to steeply plunging fold axis lineation. Interference structures show that the abundant isoclinal folds deform earlier approximately northeast-trending folds. Later tight to isoclinal folds deform the regional foliation. Metamorphic recrystallization outlasted deformation. The Kitkiata pluton has an initial ⁸⁷Sr/⁸⁶Sr ratio of 0.7042 to 0.7043, depending on its age. One radiogenic Sr-rich sample gives a model date of 165 ± 11 Ma, but the possibility of anomalous initial ⁸⁷Sr/⁸⁶Sr ratio makes this result highly uncertain. The Quottoon pluton gives a whole-rock isochron of 51 ± 2 Ma with 0.7045 ± 1 initial ratio. The low initial ratios indicate a preponderance of mantle-derived magma of Mesozoic or early Cenozoic age in the plutons studied. Sr isotopic composition of the Central Gneiss Complex is compatible with late Paleozoic-early Mesozoic ages for precursor detrital and volcanic strata and local presence of marine carbonate with moderately enriched ⁸⁷Sr/⁸⁶Sr. The generally low radiogenic Sr content of these core gneisses rules out an origin by remobilization of greatly older rocks. Plutons of the Coast Plutonic Complex may have been generated by partial melting of the Central Gneiss Complex, and emplaced not far from their source of origin during regional metamorphism, as the surrounding rocks cooled from maximum temperature and pressure of metamorphism. / Science, Faculty of / Earth, Ocean and Atmospheric Sciences, Department of / Graduate

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