Zugl.: @Diss.

Thesis (Ph.D.)--York University, 1998. / Mode of access: World Wide Web. Includes bibliographical references.

An intensive chemical investigation, that includes the determinations of salinity, oxygen, nutrients, pH, alkalinity, and total carbon dioxide of the Columbia River plume off the Oregon coast in July 1967 shows the following unique features: 1. Along the axis of the river plume both the salinity minimum and temperature maximum occur. The location of these extrema at zero, ten, twenty meters depths differ considerably, suggesting different patterns of water flow at different depths. 2. Throughout the plume region, at salinities less than 32.5%, the plume water is supersaturated with respect to dissolved oxygen, and a subsurface oxygen maximum exists at the depths of 3.0-50 meters. 3. The relationship between apparent oxygen production by marine organisms and nutrient concentrations shows biological production of dissolved oxygen is a definite cause for the oxygen supersaturation in the plume region. 4. The plume area off Oregon is a source of oxygen transfer from the ocean into the atmosphere. / Graduation date: 1969

Hydrographic and bathythermograph data taken off the Oregon coast during a two week period in August of 1969 were analyzed to determine if heat content and mixed layer depth may be used as indicators of Columbia River plume water. Heat content was found to be a poor indicator of plume water because of large additions of heat to the plume as the waters flowed southward and because the layer over which heat content was integrated (0 to 20 meters) was inconsistent with the depth of the plume. High variability among observations made analysis of mixed layer depth difficult and reduced its utility as an indicator of plume waters. Hydrographic sections taken during the summer months off Oregon from 1960 through 1969 were also examined. The axis of the Columbia River plume was located in 70 instances. The salinity axis was found to lie inshore of the temperature axis by a mean distance of 8.5 nautical miles. This displacement increased downstream and was most pronounced in July and August. A simple model showed the displacement to be the result of a large temperature gradient across the nearshore portion of the plume pynocline. / Graduation date: 1972

In this study methods were developed for the prediction of wave conditions that are hazardous to navigation at river entrances, with emphasis on applicability to the Columbia River. There are two basic components to the prediction system: (1) a semi-automated spectral method for forecasting the significant height and average period of waves in deep water, and (2) an index of navigation hazard at river entrances that depends on the significant height and average period in deep water and on the mean current and water depth at the entrance. The computerized, deep water forecast method is a hybrid scheme that combines the spectral principles of the Pierson-Neumann-James method with the graphical input techniques of Wilson and the fetch limited spectrum of Liu. The significant heights generated by the method are well verified by winter wave measurements at Newport, Oregon. The hazard index is based on the probability of wave-breaking in water of arbitrary depth and current. The breaking probability is derived under the assumption that wave heights and squared periods are statistically independent and distributed according to a Rayleigh probability density function. The breaking-wave probability and the hazard index depend on the wave steepness in deep slack water and on the depth (relative to the wave period squared) and current (relative to the period) at the river entrance. The dependence on depth and current is achieved in two ways: (1) the limiting steepness (breaking index) k found as a function of relative depth and relative current, and (2) the wave spectrum in water of arbitrary depth and current is found by transformation of the spectrum in deep slack water. The transformation is performed by requiring that the rate of wave energy propagation remain constant. The hazard index is closely related to the probability of breaking swell. At water depths that are typical of river entrances, the hazard index depends strongly on the significant wave height, mean current and depth, but only weakly on the mean wave period (since the breaking height of swell at such depths is only weakly dependent on period). Hindcasts of deep water significant wave heights and hazard indices compared reasonably well with measured heights and Columbia River bar closure periods. Forecasts based on accurate prognostic weather charts should provide similar results. / Graduation date: 1974

Thesis (Ed.D.)--Teachers College, Columbia University, 1975. / Typescript; issued also on microfilm. Sponsor: Albert S. Thompson. Dissertation Committee: Ruth Z. Gold, Walter E. Sindlinger, . Includes bibliographical references.

Thesis (Ph. D.)--Columbia University. / Bibliography: l. 573-597.

Thesis--Wisconsin. / Vita. Includes bibliographical references (leaves 266-304).

No description available.

The Roza flow of the Columbia River Basalt group in Washington State U.S.A. extruded at about 15 Ma during intermediate geomagnetic polarity. The Roza is underlain by normal polarity flows and overlain by reversed units. The Roza is an extensive flow, up to 60 in thick. As the remanence-blocking isotherms progressed into the flow, it recorded a short continuous segment of the transitional geomagnetic field. Our studies show limited thermal remagnetization in the underlying flow, and we infer that groundwater was effective in extracting the heat. The extent of basement heating was further reduced by the insulating scoria immediately beneath Roza. Hence, the Roza flow cooled symmetrically from its top and base. Samples from the drilicores acquired drilling induced remanent magnetization (DIRM), shown to be well modelled as an isothermal remanent magnetization produced in nonuniform fields of the order of 10 mT at the rim of the drillstring. Alternating field demagnetization was usually successful in removing the DIRM. The remanence stability is higher in the top third of Roza, due to smaller magnetic particles, than in the lower two thirds of the flow, where the magnetic properties are nearly uniform. The stability profile corresponds to the entablature/colonnade subdivision. High temperature subsolidus oxidation of the titanomagnetites increased with height in the flow, altering the primary symmetric intraflow distribution. The declination of the Roza flow sampled at numerous outcrops is consistently about 189°. In a 54 m drillcore section, Roza inclinations become more negative towards the flow interior, consistent with its magnetostratigraphic position. Superimposed is a symmetric, rapid change in inclination from -2 to -15° and back to -5°. The flow's thermal history predicts that these fluctuations have a characteristic time between 15 and 60 years, such that the inclination changed at a rate of 1/2 to 2° per year, showing that the directions of this transitional field fluctuated several times more rapidly than the present geomagnetic field. However, considering the generally reduced intensity during transitions, these fluctuations might not be unusual. / Graduation date: 1990