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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.
121

The Canadian Pacific railway and British Columbia, 1871-1886

Johnson, Arthur J. January 1936 (has links)
No abstract included. / Arts, Faculty of / History, Department of / Graduate
122

The mineralogy and major element geochemistry of ferromanganese crusts and nodules from the northeastern equatorial Pacific Ocean

Wade, Lowell January 1991 (has links)
A study of the mineralogy and major element geochemistry of ferromanganese crusts and nodules from the northeastern equatorial Pacific Ocean involved three inter-related projects: ft) the major element geochemistry of crusts and nodules from two study areas, (2) the development of a selective sequential extraction scheme (SSES) and a differential X-ray diffraction technique (DXRD) for the study of the mineralogy of the deposits, and (3) the application of the SSES and DXRD to a small population of crusts and nodules from the two study areas. The objectives of the first project were to relate the composition of the crust and nodule samples to the environment of formation as well as to the mineralogy which could be identified from a bulk powdered sample. The SSES was developed to determine the partitioning of Cu, Ni, and Co concentrations between the Mn and Fe oxides present in crusts and nodules. In developing a SSES, two goals had to be attained: (1) since crust and nodule samples are finite in size and numerous different analyses are to be preformed on a single sample, a SSES should be developed which uses as small amount of sample as feasible, and (2) develop a SSES which is as time efficient as possible. The development of the DXRD in conjuction with the SSES identified which Mn and Fe oxide mineral phase was responsible for hosting Cu, Ni, and Co. In developing the DXRD procedure two other goals had to be attained: (1) use of small leached samples, and (2) recovery of the sample aafter XRD analysis. The purpose of the third project was to test the two analytical procedures on a group of crust and nodule samples which have a wide range in compositions and oxide phase mineralogies. One group of hydrothermal nodules, from Survey Region B, was found to be enriched in Mn and depleted in Fe and Si. The Mn-rich mineral phases were identified as todorokite and birnessite. The second group of hydrothermal nodules, from Survey Region B, was found to be enriched in Fe and Si and depleted in Mn. The Fe-Si rich mineral phase was identified as iron-rich nontronite. Both groups of hydrothermal nodules were depleted in Co, Cu, and Ni. Dymond et al. (1984) and Chen & Owen (1989) identified one group of hydrothermal nodules located close to the East Pacific Rise (EPR) as being enriched in Fe but depleted in Mn, Cu, Ni, and Co. This composition agrees with the Fe-Si rich hydrothermal nodules identified in Survey Region B. Both Dymond et al. (1984) and Chen & Owen (1989), however, interpreted a second group of nodules, close to the EPR, which were enriched in Mn but depleted in Cu, Ni, and Co as suboxic diagenetic deposits. This group of nodules is the Mn-rich end-member composition of hydrothermal nodules identifed in this study. The composition of nodules from Survey Region B indicates there is a correlation between Co abundance and the proximity of the nodules to the hydrothermal discharge from the JEPR. Nodules that are Co-enriched are found farthest away from hydrothermal activity. In contrast, cobalt-depleted nodules coincide with known areas of hydrothermal activity. The SSES and DXRD was applied to a small population of crusts and nodules from the two Survey Regions. The DXRD patterns from the second stage of leaching on the crusts and nodules showed that the iron phase mineralogy in marine crusts and nodules is either akaganeite or ferrihydrite. The DXRD patterns from the second stage of leaching on the Mn-rich hydrothermal crusts and nodules, from Survey Region B, identified the Mn-bearing mineral hausmannite. / Science, Faculty of / Earth, Ocean and Atmospheric Sciences, Department of / Graduate
123

The effect of intertidal exposure on the survival and embryonic development of Pacific herring spawn

Jones, Barry Cyril January 1971 (has links)
Eggs of Pacific herring were exposed to air for different periods of time in simulation of tidal effects on spawn deposits at varying beach heights. The maximum exposure range was 2/3 of a 24 hour day corresponding roughly to the exposure of eggs at 4 meters above mean low tide on the British Columbia coast. Egg size, spawning fish length, and egg clump size were examined as secondary factors modifying the effect of exposure. Incubation time dropped from 19 to 18 days with only two 2-hour periods of exposure per day and thereafter fell slowly. It is suggested that oxygen deprivation triggered a hatching response for the initial drop, whereas the gradual decrease was due to a higher air temperature increasing metabolism. Hatching mortality rose steadily from an unexposed 13% to 31% at maximum exposure time, with significantly higher contributions from eggs of smaller fish and smaller egg clumps. Larval length at hatching for the unexposed eggs was 7.7 mm.; lengths for all degrees of exposure were similar (7% less than for no exposure). Larval weight (body plus yolk) remained relatively constant (0.099 mg.) until the longest exposure period when it dropped to 0.087 mg. This decrease coincided with similar sharp trends in incubation time and hatching mortality, and suggests a "critical point" near the upper experimental range of exposure, above which eggs stand little chance of normal development or survival. Beach surveys to note possible egg size stratification, although suggesting the deposition of larger eggs at the top levels, proved inconclusive, but point up the possibility that a heavy fishing pressure which reduces mean fish size might detrimentally affect potential stock recruitment via the intertidal exposure effect on the spawn. / Science, Faculty of / Zoology, Department of / Graduate
124

Some oceanographic features of northern Chilean waters in July, 1962

Inostroza Villagra, Hector M. January 1966 (has links)
A description is presented of some of the oceanographic features of the northern Chilean waters as indicated by a study of the distribution of properties and of direct current measurements during the Marchile II Expedition, 1962. A narrow band of cold, low salinity water of low oxygen content close to the coast; an oxygen minimum layer from 50 to 400 m and the permanence of the Peru - Chile undercurrent are the outstanding features of the area. The process of upwelling is suggested as the main cause of the distribution of properties near the coast. However this process of upwelling was probably in a quiescent state during the Marchile II Expedition, being much less intense than during other expeditions in the same area, and than in other similar upwelling regions of the world. / Science, Faculty of / Earth, Ocean and Atmospheric Sciences, Department of / Graduate
125

Contributions to the life history and ecology of the marine brown alga Phaeostrophion irregulare S. et G. on the Pacific coast of North America

Mathieson, Arthur Curtis January 1965 (has links)
Until recently, few collections of the marine brown alga Phaeostrophion irregulare S. et G. had been made, little was known of its ecology, and virtually nothing of its life history. The main objectives of this investigation were to study the life history and major factors influencing growth and distribution of this species. Laboratory and field investigations were conducted during 1961-196i4. Life history studies were performed in the laboratory by culturing zoospores under constant environmental conditions. The growth of cultured germlings and the photosynthetic response of the laminate plants from the field were recorded under different temperatures, salinities, nutrients, and light conditions. The tolerance of laminate plants and germlings to extremes of temperature, salinity, and desiccation was also determined in the laboratory. The growth and reproduction of in situ plants at Glacier Point, British Columbia were correlated with temperature, salinity nutrients, tides, sand and various meteorological conditions at that locality. Life history studies were conducted at Glacier Point by observing the succession of germlings on denuded transects and by transplanting laboratory cultured germlings into the field. The laminate thallus of P. irregulare sometimes bears both unilocular and plurilocular sporangia at the same time. Previously, only unilocular sporangia were reported in this plant. Zoospores from the unilocular sporangia (unispores) and plurilocular sporangia (plurispores) develop identicallys, and each is capable of producing a laminate thallus directly or after a succession of filamentous and discoid plethysmothalli. The "direct-type" of development of the zoospores (unispores) from the unilocular sporangium is probably due to a suppression of meiosis in the unilocular sporangium. Morphological and cultural evidence is presented to support this hypothesis, although no cytological evidence was obtained. At Glacier Point, P. irregulare is restricted to sandy areas, and the greatest number of plants occur where large fluctuations of sand occur annually. The plants are regularly buried four to six months per year, and their growth and reproduction is limited to the period when sand is absent. Competition with other plants probably accounts for the occurrence of P. irregulare in sandy areas, since it will grow in rocky areas if other algae are eliminated. The period of maximum growth (February to April) is associated with a corresponding increase in light intensity and water temperature in this area. After April, growth in non-tide pool populations decreases much more rapidly than growth of tide pool populations, because of the increased exposure of plants to desiccation during daylight. A period of decreased growth for tide pool plants occurs in May to June; this decrease probably results from high surface water temperatures, high light intensities, or a combination of both. The morphology of the laminate plants of P. irregulare is extremely variable and the range of variability observed at Glacier Point overlaps that described for P. australe from Callifornia. P. australe is considered to be a growth form of P. irregular, and is therefore a taxonomic synonym of P. irregulare, Distributional evidence also supports this conclusion. The known range of P. irregulare extends from Point Conception, California to Khantaak Island, near Yakutat, Alaska. Temperature is considered to be the primary factor controlling its gross distribution. Nitrate and phosphate deficiency may partially restrict the distribution of P. irregulare south of Point Conceptions, California. The sporadic distribution of P. irregulare on the Pacific Coast is correlated with the presence of sand, and local conditions are most important in determining its regional distribution. Experimental studies show that P. irregulare is well adapted to a sandy habitat, and several features are discussed to explain this adaptation. The laminate plants and germlings of P. irregulare tolerate a wider range in temperature and salinity in culture than that to which they are subjected in nature. However, the laminate plants and germlings of P. irregulare are very sensitive to desiccation; under experimental conditions both tolerate less desiccation than that to which they are subjected under natural conditions. / Science, Faculty of / Botany, Department of / Graduate
126

Theoretical studies of the circulation of the Subarctic Pacific Region and the generation of Kelvin type waves by atmospheric distrubances

Thomson, Richard Edward January 1971 (has links)
Theoretical studies of two problems concerned with the surface forced, large-scale motions in bounded oceanic regions are presented. In Part I, such motions are considered for a particular area of the North Pacific Ocean known as the Subarctic Pacific Region. Discussion is based on the assumption that the velocity components may be separated into a time-averaged or quasi-steady flow about which fluctuations occur in the form of transient planetary waves. Some of the characteristics of the latter are briefly outlined. Several aspects of the time-averaged motions are then considered. A simple circulation, driven by the vertical velocity structure, is presented for the interior region of the ocean below the upper frictional layer. Also, using observational data to obtain the depth of the layer between the suface [sic] and the main halocline, this upper layer is found to behave as a geostrophic layer of fluid when averaged over many years. Combination of the above observed depths with the mean calculated Ekman divergences permitted calculation of a mean eddy coefficient of diffusivity for density. The results agree very well with those obtained by Veronis for similar oceanic situations. An explanation for the variations in the intrusion of 'warm' water along the top and bottom of the halocline off the coast of British Columbia is also given. The two final sections of Part I deal with the overall, quasi-steady circulation of the Subarctic Pacific Region. Here, a theoretical study is combined with the mean-monthly values of the calculated surface forcing. Curvilinear coordinates are used in order to model the northern boundary formed by the Aleutian-Komandorski island chain. The interior quasi-steady flow, which satisfies a Sverdrup-type balance of vorticity, is closed to the north by a frictional boundary layer. Using mean-monthly values for the surface winds over the region, the observed separation of the eastward flowing West Wind Drift into a northern and southern tending flow is found to correspond to the zero of the mean wind-stress curl. In the northern boundary layer, the characteristics of the westward flowing boundary current there, are shown to change downstream from a Western' to a 'zonal', type boundary current. The stability of the latter is dependent upon vorticity of appropriate sign being added to the boundary layer flow to balance that generated by friction along the coast. Discussion is also given for the effect of passes between the Aleutian islands on the zonal boundary current. Through a type of boundary layer 'suction' or, alternately, by mass transport into the boundary layer, the effect of these passes would seem to be to keep the boundary flow attached to the coast. Finally, spectral analysis of the wind-stress curl data, obtained from the mean-monthly surface pressure, is performed to determine its frequency distribution. A demodulation technique is used to determine the time variations of six of the frequency bands obtained in the spectral analysis. These results are then applied to the circulation in the Subarctic Pacific Region in an attempt to relate variations and spatial distribution in the circulation with the applied winds. The generation by the atmosphere of a type of long, boundary waves, known as Kelvin waves, is considered in Part II. In particular, it is shown that for a general large-scale distribution of wind and pressure systems that only the longshore component of the wind-stress and pressure can generate such waves. Examples are presented for a semi-infinite wind and moving pressure pattern. Kelvin waves are shown to move away from the force discontinuities at the speed of shallow-water waves. These waves are further found to exhibit a frequency shift, typical of non-dispersive waves from a moving source. Using some observed parameters for the atmospheric forcing terms off the Oregon coast of the United States, numerical values for the wave amplitudes for both examples are given. Part II has been published in the form presented here. Reference: J. Fluid Mech. C1970), 42C4), 657-670. / Science, Faculty of / Earth, Ocean and Atmospheric Sciences, Department of / Graduate
127

Structure of the northeast Pacific wave cyclone of 19 November 1980

Gratham, Christopher H. January 1991 (has links)
The frontal system that passed over the Storm Transfer and Response Experiment Study area on 19 November 1980 was the third vigorous system in succession to affect this region of the northeast Pacific Ocean. This study marks the first detailed investigation of a frontal wave over the Gulf of Alaska and as such provides structural details not shown in other studies. Precipitation and changes in temperature, wind velocity, and pressure were associated with the passage of both the warm and cold fronts. The thermal structure exhibits a well defined warm sector with regions of large baroclinicity in both the warm and cold frontal zones. Data from radiosonde releases from the northern-most of two observing platforms indicate a mid-level upper moisture front above the kata cold front. Throughout these northern cross-sections, gradients in the warm and cold frontal zones are of similar magnitudes while sections from the southern ship show a warm frontal zone that is more intense than the cold transition region. Along-frontal gradients of equivalent potential temperature are of the same order of magnitude as the cross-frontal gradients. Horizontal wind components relative to the storm indicate strong inflow to the system at lower layers from both south and east. The wind exits the system to the west and south. Upper level winds are westerly throughout. Gradients of wind components are strongest in frontal zones, which results in the cold front coincident with the peak axis in the vertical component of relative vorticity. The field of horizontal divergence also exhibits its largest magnitudes in the frontal zones, with convergence in the warm frontal zone and divergence in the cold transition region. This seldom observed feature of divergence at the cold front leads to a downwelling motion in this region and categorizes the front as a kata-cold trout. Most of the upward vertical velocity occurs in and around the warm frontal zone as a result of horizontal convergence in this region. Relative isentropic analysis indicates that there are three main air streams within the system. The warm conveyor belt flows to the north in the warm sector and rises gradually as it makes it way to the north. Ahead of the warm front and behind the cold front are two cold air streams that flow to the north and south respectively. Analysis of the kinematic, frontogenesis indicates that confluence and infrequently studied shear effects are the most important processes influencing the frontal gradients. Analysis of uncertainty in the terms of the prognostic kinematic frontogenesis equations reveals that the diabatic heat and twisting terms that others have found important are smaller than their estimated errors in this study. / Science, Faculty of / Earth, Ocean and Atmospheric Sciences, Department of / Graduate
128

True wayfaring Christians: form and meaning in the Overlander narratives

Sawadsky, Joanne Marie January 1976 (has links)
The basic contention of this thesis is that the journals and memoirs of a famous Canadian expedition—that of the "Overlanders" to the Cariboo gold fields in 1862—have literary as well as historical value. The accounts may be read as autobiographies, or as classic adventure stories (romances). The first chapter seeks to define the criteria by which we "judge literary worth in these two forms, and indicate in;: general terms how the Overlander narratives fit into both genres. The second chapter is concerned with dramatic structure in the narratives. The plot, reduced to its simplest form, is seen to be essentially that of the traditional folk tale ("naive" romance), in which heroes ride off in search of fabulous treasure, and on the way must overcome a variety of staggering difficulties. Although the outline of the plot in the Overlander accounts was supplied by actual events, the authors' ability to recognize the drama and reproduce it effectively is evidence of their creative power. The third chapter examines the diction, sentence structure, and imagery of each of the narrators. Their artistry and originality is perhaps more apparent in their style than in any other aspect of their writing. The fourth and fifth chapters concentrate on autobiographical meaning in the accounts. This meaning is developed as the travellers are shown striving to maintain harmony among themselves, and struggling to make progress in a sometimes hostile wilderness. All the narrators were Christian believers. Their religious vision was reaffirmed in the course of the trek, and broadened and deepened by their experiences. This vision and the process of its expansion, re-created by the authors, provide unity and a sense of progression for their works. In the final chapter, an attempt has been made to place the Overlander narratives in the context of the Canadian literary tradition. They belong to a large body of early travellers' and explorers' narratives which are full of fascinating details and curious anecdotes, and possess drama, poetry, and psychological interest, but which are just beginning to be recognized as genuine and valuable imaginative literature. Even after the fairly extensive analysis which can be made in a study of this length, it does not seem possible to state exactly how much literary value exists in works which are as little known as these, especially since what is true . of one or several may not be true of all the narratives. This examination does indicate, however, that these accounts taken as a whole possess both form and meaning and will give almost any reader pleasure on many levels. / Arts, Faculty of / English, Department of / Graduate
129

Northwest Coast traditional salmon fisheries systems of resource utilization

Berringer, Patricia Ann January 1982 (has links)
The exploitation of salmon resources was once central to the economic life of the Northwest Coast. The organization of technological skills and information brought to the problems of salmon utilization by Northwest Coast fishermen was directed to obtaining sufficient calories to meet the requirements of staple storage foods and fresh consumption. This study reconstructs selective elements of the traditional salmon fishery drawing on data from the ethnographic record, journals, and published observations of the period prior to intensive white settlement. To serve the objective of an ecological perspective, technical references to the habitat and distribution of Pacific salmon (Oncorhynchus sp.) are included. The aim of the work is to assess the relationship of salmon technology complexes to ecological conditions at fishery sites. It is an examination of the operating principles in traditional systems of salmon production. A model of the fishery is suggested: during migration anadromous salmon pass through a number of time and space segments where they can be intercepted by fishermen. A coincidence of appropriate elements will define a fishery site, i.e., the characteristics of the prey, accessibility to resource locations, natural features of the environment, and the enterprise of fishermen. The interaction of these and their constituent variables provides a range of selective strategies to be used, analyzed in this study with reference to specific Northwest Coast ethnic divisions and geographic locations. Twenty-four ethnic or areal divisions within the Northwest Coast culture area were studied. The results of the research are presented in Part One supported by distribution maps and illustrative materials. Lists of reference tables for each of twelve systems of salmon production are contained in an Appendix. Part Two includes technical information about Oncorhynchus sp. and its habitat. Part Three is an analysis of social, ecological, and technological elements in several stages of inter-relation, including an interregional comparison in the final section. An Index of Salmon Abundance and a comparison of selected resource areas provide statistical evidence (Appendix II and III). / Arts, Faculty of / Anthropology, Department of / Graduate
130

Movement and demography of larval coastal giant salamanders (Dicamptodon tenebrosus) in streams with culverts in the Oregon Coast Range /

Sagar, Jina P. January 1900 (has links)
Thesis (M.S.)--Oregon State University, 2005. / Printout. Includes bibliographical references (leaves 64-72). Also available on the World Wide Web.

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