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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.
191

PALEOSEISMOLOGY OF A PLIOCENE EARTHQUAKE IN EASTERN TAIWAN

Korren, Caitlyn 01 May 2015 (has links)
High seismicity coupled with high population density creates a recipe for high seismic risk in Taiwan. Taiwan is located at the convergences of the Eurasian and Philippine Sea plates. These convergences result in the development of an accretionary wedge. A basal decollemont bounds the NE-SW trending thrust packages. The most Eastern thrust package, the Central Range, experiences high erosion rates and exhumation rates which may induce high seismicity. Paleoseismic indicators improve the ancient seismic history and may aid in the constraint of geologic processes of an accretionary wedge. Pseudotachylytes, known as earthquake fossils, form by frictional melting during seismic slip. Cataclasites form by comminution during sliding. Frictional melts serve as a window to the fault plane. Pseudotachylytes may allow for the assessment of focal parameters through the utilization of fault plane geometry and slip surface properties. This study provides the first microstructural evidence for fault pseudotachylytes at the Hoping River locality in Eastern Taiwan. The 3.3 Ma Hoping River frictional melt evidences an ancient Mw 6.4 ±0.40 earthquake. This pseudotachylyte demonstrates an oblique fault with a reverse component which corresponds to the orientation of the thrust packages in the accretionary wedge. Sense of slip of both pseudotachylytes and cataclasites suggest a uniform stress field. Narrow fault cores suggest high strain localization. Coeval pseudotachylyte and quartz-calcite veins suggest shear heating as a mechanism, if a fluid reservoir along the basal decollemont in Taiwan exists.
192

Aspectos taxonômicos, alimentação e reprodução da raia de água doce Potamotrygon orbignyi (Castelnau) (Elasmobranchii: potamotrygonidae) no rio Paraná-Tocantins /

Rincon Filho, Getulio. January 2006 (has links)
Orientador: Miguel Petrere Júnior / Banca: Roberto Goitein / Banca: Paulo Emílio Vanzolini / Banca: Otto Bismarck Fazzano Gadig / Banca: Teodoro Vaske Junior / Doutor
193

Systematics and biogeography of Mesobola brevianalis (Boulenger, 1908) (Teleostei: Cyprinidae)

Riddin, Megan Amy January 2015 (has links)
The accurate identification of fish species, their life stages and their products enables the correct management of fisheries, research and conservation of distinctive populations for long-term survival and sustainability. Mesobola brevianalis Boulenger, 1908, commonly known as the river sardine, is found in many river systems in southern Africa. Because it exhibits widely separated populations showing subtle differences, particularly in colour, it is thought that there may be cryptic species involved. Standard phylogenetic techniques using three genetic markers (mitochondrial COI, nuclear protein RAG1 and nuclear ribosomal 28S rRNA), enabled the building of phylogenetic networks for M. brevianalis and some outgroup species. Consistent patterns of relationship were seen with 28S supporting monophyly. COI and RAG1 suggested that populations that are currently identified as M. brevianalis in fact represent several species. There was sufficiently strong support for the evolutionary independence of the M. brevianalis populations from the Rovuma, Kunene and Orange River Systems to consider them as independent species. The independence of the genus Mesobola was brought into question because Engraulicypris sardella and Rastrineobola argentea were placed within it phylogenetically.Morphometric methods in the form of multivariate truss network analyses, were performed to locate morphological markers for populations. There was little to no variation among most of the populations synonymized under M. brevianalis. Furthermore, neither latitude nor longitude had an effect on the morphological characters that might be linked to functional evolution. A molecular clock analysis of COI data was used to calibrate a paleobiogeographical model which entailed a divergence of lineages starting from an easterly reigning Paleo-Congo Basin, via a hypothetical Paleo-Kalahari Lake that was fragmented by a series of uplifts and drying events beginning ~65 million years ago. Complete evidence supported the synonymisation of the genera Engraulicypris and Mesobola, the resurrection of the species name gariepinus for the Orange River Systempopulation, and the description of two new species: E. ngalala from the Rovuma River System and E. howesi from the Kunene River System.
194

Early history of the Fraser Valley, 1808-1885

Gibbard, John Edgar January 1937 (has links)
[No abstract available] / Arts, Faculty of / History, Department of / Graduate
195

Ice distribution in the Gulf of St. Lawrence during the breakup season

Forward, Charles Nelson January 1952 (has links)
The Gulf of St. Lawrence Is closed to commercial navigation for nearly five months each year due to ice conditions. In order to lengthen the shipping season, greater knowledge of the behaviour of the ice is necessary. A step in this direction was the inauguration in 1940 of aerial ice surveys in the gulf during the breakup season. The surveys have continued annually for the past thirteen years. Based primarily on the data provided by these surveys, maps were drawn showing the limits of the main ice areas in each breakup season. Although the maps enabled the isolation of several distinct patterns and rates of breakup, they revealed that the behaviour of the ice was extremely variable. The factors influencing ice conditions, including tides, ocean currents, temperature, and wind, were examined with the aim of discovering the causes of the breakup patterns. A number of factors were found to be important in determining the fundamental behaviour of the ice, bat the meteorological factors of temperature and wind appeared to be the chief agents in causing the variable behaviour from year to year. In spite of these variations, it was possible to trace average conditions throughout the Ice season. The chief characteristics of the ice season may be stated briefly. The Gulf of St. Lawrence is never completely covered with ice, but rather, it is partly covered with fields of shifting pack ice between which lie broad stretches of open water. The southern part of the gulf is an area of accumulation where ice conditions are most serious. The clearing of ice from the gulf begins slowly in January and February and becomes accelerated in March and April. The bulk of the ice moves through Cabot Strait to the open Atlantic rather than remaining inside the gulf until it melts. Generally, the ice either withdraws from west to east, passing through Cabot Strait directly, or it stagnates in the southern part of the gulf toward the end of the season. By the first of May the gulf is usually clear of ice which constitutes a hinderance to navigation. / Science, Faculty of / Earth, Ocean and Atmospheric Sciences, Department of / Graduate
196

The Bridge River region a geographical study

Wood, George Alan January 1949 (has links)
The Bridge River Region is a mining district situated in southern British Columbia on the eastern side of the Coast Range. The boundary of the region is defined by the drainage basin of Bridge River above Moha. The region is isolated. The geology is complex, and highly metamorphosed sedimentary, volcanic and intrusive rocks are present. The rocks range in age from Permian to Recent. Mineralization is thought to be linked with the location of the region on the eastern margin of the Coast Range batholithic intrusions. The topography is mountainous and strongly glaciated. The hanging valley of Bridge River is the deepest erosional feature of the district. Generally, the valley is at an elevation of 2000 feet, and the flanking Bendor and Shulaps ranges rise to 8000 and 9000 feet. The rugged nature of the country makes transportation especially difficult. Towards the Chilcotin Plateau, the mountains are more subdued in character. During the snow-free season, sheep and cattle are pastured in the alpine grazing ranges of this transition belt of mountains. The country is also the habitat of big-game animals which are a resource of the tourist industry. The Bridge River Region has many climates because of great relief. As a whole, the climate is continental, although continentality is modified by proximity to the Pacific Ocean. The annual average temperature in the main area of settlement is forty degrees and the annual average precipitation is twenty-four inches. Four months have average temperatures below freezing. The country is forested but timber is generally of little commercial value. Ponderosa pine, Douglas fir and Lodgepole pine are the basis of a small-scale forest industry. The industry is largely subsidiary to mining. Trapping is a part-time occupation based on the fur-bearers of the region. The many creeks of the district head from snow-fields and glaciers. Hurley River and Cadwallader Creek have been developed for hydro-electric power. Bridge River, which has its source in extensive ice-fields, ultimately will produce 620,000 horse power. Most of this power will be supplied to Vancouver and the Lower Mainland. Rapid run-off makes storage dams necessary. The resultant flooding obviates most agricultural development. Historically, mining has been the dominant industry of the Bridge River Region. Beginning in 1858, miners came into the district seeking placer gold. Their sporadic and desultory activity gave place to the more permanent lode gold mining around 1898. In modern times, Bralorne and Pioneer Gold Mines have developed as successful producers. Efficient transportation has come to the region by the building of the Bridge River highway which provides a link with the Pacific Great Eastern Railway. Bralorne and Pioneer are small-scale, fully mechanized mines. Most of the ore is produced by shrinkage and cut and fill stoping. Bralorne ranks first as a gold producer in British Columbia and Pioneer holds fourth place. The known reserves at both mines will last eight years at present rates of production. Much exploration work is going on in the district to bring other mines into production. The population of about two thousand persons in the Bridge River Region is almost entirely dependant upon mining. Three quarters of the people live in the company towns of Bralorne and Pioneer. The destiny of future settlement rests largely with the mining industry. / Arts, Faculty of / Geography, Department of / Graduate
197

The Red River Resistance of 1869-1870: The Machiavellian Moment of the Métis of Manitoba

O'Toole, Darren January 2010 (has links)
In October 1869, the fledgling Canadian federation was preparing for the transfer of Rupert's Land and the Northwestern Territory when the Métis set up a Provisional Government in order to resist what they saw as a unilateral annexation of their homeland. Although there were multiple references made to 'republicanism' during the Resistance, no scholar has ever explored whether republican conventions were actually present in political discourse in the District of Assiniboia prior to the Resistance and whether they were effectively activated during the Resistance. Working from the Cambridge School approach of discourse analysis, this thesis first identifies the conventions of democratic rhetorical republicanism, which includes positive and negative liberty, the rule of law, the mixed and balanced constitution and citizenship, which in turn involves virtue, the militia and real property. It then looks at the gradual introduction in Assiniboia of republican discourse from multiple sources, including the United States, Lower Canada, Upper Canada, Ireland, France and Great Britain and its circulation throughout several practical political struggles during the period from 1835 to 1869. In doing so, it shows that certain 'organic intellectuals' acted as 'transmission belts' of republican conventions and that institutional structures were a factor that rendered the activation of such conventions almost inevitable. By the time the Resistance took place in 1869, a more or less fully developed republican paradigm formed part of the linguistic matrix and was available to political actors in Assiniboia. Finally, the thesis shows that republican discourse was effectively mobilised by identifying fragments of republican conventions that were harnessed in various speechacts during the Resistance. It is argued that republican language was fundamental to the success of the ideological and political manoeuvres of the leaders of the Resistance as it was particularly effective both as an instrument of anti-colonialism and as a pragmatic ideal of self-government that sought to correct the iniquities of colonial government.
198

Goals and their realization in planning and building an instant town : Gold River

Lozovsky, Nicolas January 1970 (has links)
The development of resources has always been one of the important factors of Canadian economy. As Canada's resource and industrial frontier extends further to the north, lasting and self-sufficient communities have become increasingly difficult to create. The first settlements were not permanent and the inhabitants' needs and demands were limited. With time needs and demands evolved and became more complex in nature. The evolution of such settlements from camps, through company towns, to incorporated towns can be traced in terms of these demands and needs. Instant resource towns, unlike, camps or company towns, are the result of a rather complicated planning process. The goal formulation of this process is much more complex, involving many external factors. Goal specification, especially where explicit goals are concerned, becomes not only a function of the criteria set, or the needs of the inhabitants, but also of the different needs and interests of each of the individual planning and policy making bodies. The purpose of this thesis is to examine the process involved in the creation of Gold River, an instant town. The planning and building processes will be examined in order to determine the discrepancies between the goals specified, both, explicit and implicit, in the planning process and the final product. The aim of the study is, therefore, to analyse the different circumstances and factors that lead to the creation of Gold River and the philosophy of the different people who contributed to it. The planning process, concerned specifically with Gold River, is analysed. An attempt is made to differenciate between the different explicit and implicit goals of each of the individual planning bodies involved. Through the analysis of this process, both, positive and negative results are studied. The method of study consists of a comparison of goals expressed in the planning process, by the different bodies interested, with the results achieved. Such comparison will allow the author to determine to what extent some of the goals have been achieved and will show how the performance of the physical environment relates to the expectations. The study is based on the results of a questionnaire gathered on a field trip to the town. The goals of the different planning bodies were determined by interviewing the parties concerned and by analysing published pamphlets concerning Gold River development. The study also describes Gold River in its different aspects as the author saw it from direct observation and from information obtained from other sources. Furthermore, an evaluation of the physical, economic and social aspects of the town in terms of user satisfaction or dissatisfaction was derived from the questionnaire. The analysis and evaluation of achievements reveals some of the causes of user dissatisfaction, high population turnover and instability to be inherent in the planning process. Achievements are considered from the point of view of both: the different planning bodies and the inhabitants. The conclusions support the hypotheses that: - Discrepancies between the inhabitants' expectations of the town and the actual reality have profound social implications. - Goal misinterpretation and partial realization is due to lack of communication between the different bodies involved in the planning process. - In the planning process goals should be expressed explicitly and clearly. The study has also shown that the problem of isolation, lack of diversity, population turnover and, lack of growth, which plagued resource towns in the past, still are major problems in the incorporated, ultramodern, instant town of Gold River. This indicates that in the planning for such towns: - The size and density of the community should be taken into consideration. - Growth and diversification of industries, as factors necessary to make a place lasting and livable, should be kept in mind. - It should be emphasized that the stability of a community is a function of the population turnover. - It is necessary to provide for substantial recreational facilities. The phenomenon of Instant towns is a recent innovation in this province and should be better understood and thus improved. This study is an attempt to contribute to a better understanding of the factors involved in the creation of such a town and therefore may be instrumental in the creation of other, better towns. / Applied Science, Faculty of / Architecture and Landscape Architecture (SALA), School of / Graduate
199

Patterns of channel change on Chilliwack River, British Columbia

Ham, Darren Gary 11 1900 (has links)
This study investigates changes to channel morphology along Chilliwack River in southwest British Columbia, and relates these changes to the transport of bed material. The channel was mapped using a stereoplotter from a sequence of historical aerial photography between 1952 and 1991. Maps for selected years were overlaid, then analyzed with a GIS. Erosion and deposition volumes of bed material were determined by multiplying measured planimetric changes by the varying depth of bed material along the river. A sediment budget framework was used to estimate bed material transport rates from these net changes in stored sediment volumes. The transport rate of bed material for Chilliwack River is estimated as 55,000±10,000 m3/yr for the period 1983 to 1991. Instability along lower channel reaches has increased over the 40 year period of study due to an increase in both the magnitude and frequency of large floods. As a consequence, channel width, bank erosion rates and the volume of sediment transported past Vedder Crossing became increasingly large. Between 1952 and 1975, Chilliwack River was in a transient state of equilibrium as the channel continued to recover from a sequence of large floods in previous decades. Large floods in 1975 and 1980 caused significant bank erosion along lower reaches, which increased the amount of sediment available for transport. Extreme floods in 1989 and 1990 caused further erosion, and in fact, were large enough to alter the pre-flood channel regime. However, in the absence of further large floods, the channel should recover from these events in 10 to 20 years. Significant morphologic change on Chilliwack River occurs roughly once every 5 years, when peak flows exceed 500 m3/s. These floods are sufficient to erode channel banks, where the dominant supply of mobile bed material is stored. Aggradation occurs in the short term as more sediment is introduced to the active channel zone than can be removed by subsequent smaller flows. However, as flows as small as 250 m3/s (which occur several times per year, on average) are capable of mobilizing bed material, there is net degradation over the longer term. As the length between survey dates used in this study averaged 10 years, some information on bed material transport between dates is lost. Nonetheless, this study has demonstrated that considerable information on historic channel change can be obtained form aerial photographs. / Arts, Faculty of / Geography, Department of / Graduate
200

Environmental concepts and the management of the Fraser River : an examination of the preferences of individuals involved with the appeals over municipal sewage treatment standards at the Annacis Island plant

White, Sharlene Wendy January 1976 (has links)
The Fraser river is an essential, multi-purpose resource involving the interests of every community in the lower mainland of British Columbia. Inevitably there is a continuing public dialogue about the use of the river and consequently about the water quality standards, management strategies and the technologies which will sustain the desired uses. This public discussion was recently focused upon the regional sewage treatment facilities under construction at Annacis Island in the lower main arm of the river. Planners need to refine their understanding of such public dialogue to help them in analysing environmental management policies, communicating with clients and educating communities about the best way to achieve their environmental goals. The study was exploratory and experimental. The primary aim was to identify and advance our understanding of the concepts and conceptualising processes which caused individuals, concerned about water quality standards in the lower Fraser river, to prefer different management strategies for the Annacis Island plant. The central hypothesis was that an individual's environmental management preferences could be more usefully explained and more accurately predicted in relation to his conceptualising preferences than in relation to aspects of his background experience such as occupation and education. The study was completed in four stages: 1. The repertory grid technique, developed by the psychologist George Kelly, as a means of investigating the ways in which an individual rationalises about his environment, was adapted to the Fraser river situation. Later it was applied as a major investigative technique within the questionnaire framework. 2. The literature about the Annacis Island case was reviewed and summarised to provide the empirical framework for the study. 3. A questionnaire was designed and administered, in person, to thirty individuals. Ten individuals were chosen to represent each of three public interest groups who had been vocal in the discussion about the Annacis Island plant. The groups involved were the fishing industry, environmental organisations and water quality managers. Information was solicited on three topics: a. The respondent's background experience, especially his use for the river, occupation and education. b. His management preferences for the regional sewage system, especially for the Annacis Island plant. c. His conceptualising preferences, especially the way in which he distinguished between attributes of the water environment. 4. The information created by the questionnaire was categorised and subjected to statistical analysis. The repertory grid technique was successful in eliciting information about the way in which people construe the river environment. Respondents demonstrated a universal preference for thinking about things found in the Fraser river in terms of four general distinctions: whether they were living or inert, man made or natural, did or did not harm the life in the river and either affected or were affected by the other things they contacted in the river. The respondents were most clearly differentiated by more specialised ways of thinking about the river environment. For example, they were distinguished by their preference for thinking in terms of ecological systems, management systems and abstract technicalities. Although these factors were not satisfactorily linked with management preferences they should be reconsidered in future studies. Conceptual complexity was the only factor decisively linked with management preferences. Those respondents who preferred to use a variety of concepts and information simultaneously were shown to have a greater preference for using both conservationist and innovative strategies in the management of the regional sewage facilities. / Applied Science, Faculty of / Community and Regional Planning (SCARP), School of / Graduate

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