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In this thesis, the interpretation and reduction of ocean heat flow measurements are discussed on the basis of theoretical models. The instrument effect x heat flow measurements is investigated for the case of long period measurements by studying the heat conduction along the measurement probe for both steady and unsteady state bottom temperatures. This effect is found to be unimportant. Measurement errors due to recent bottom temperature transients are studied and the possible magnitude of such errors is estimated. Moreover, effects of climatic variation on the ocean floor temperature are estimated on the basis of diffusion models. It is shown that climatic variations with periods longer than one thousand years will be unattenuated and will affect the entire ocean floor. The perturbation method is used to study the effects of an irregular topography and a variable thickness of ocean floor sediments on the heat flow. Some special examples are given to provide a comparison between the perturbation solutions and exact solutions of similar problems. The perturbation method is also applied to a buried body with different thermal conductivity from its surroundings and the reliability of the perturbation solution is examined. Heat flow anomalies due to heat transport by magma intruded into crustal layers is studied by solving the heat conduction equation. It is shown that magmatic intrusions can lead to very large surface heat flow anomalies. Finally, the possibility of deriving the ocean floor thermal gradient on the basis of on-ship measurements performed on sediment cores is investigated. The results appear positive. The temperature variations in flowing wells and the temperature variation in a cylindrical sediment core influenced by the movement of water along the axis of the core are also studied. / Graduation date: 1968

Graduation date: 1968

Graduation date: 1969

Sea level and current data collected near Newport, Oregon are compared to determine an empirical relationship from which the low frequency (f < .1 cpd) alongshore current field over the continental shelf is estimated from observed sea level measurements at the coast. Regression analysis of the near-surface (20-25 m) currents with sea level indicates the surface currents are in geostrophic balance with the sea surface slope. Analysis of the alongshore shear between the near-surface and deep (75-80 m) layers with sea level shows the thermal wind relationship holds. A near-surface regression model is developed from which the mean monthly alongshore current 20-25 m below the surface can be estimated with a standard estimate of error (σ[subscript ER]) less than six cm/sec. The annual range at this depth is nearly 60 cm/sec. A regression model for the alongshore shear is formed from which the mean vertical shear is estimated with a σ[subscript ER] of .07-.10 cm/sec/m. The annual range is approximately .8 cm/sec/m. The surface currents are found to be predominantly driven by the local meteorological conditions. Deep and near-bottom current observations suggest the deep layer currents are primarily influenced by the thermal wind relationship and the location of the California Undercurrent. / Graduation date: 1977

Direct measurements of vertical water motions were made in the Oregon coastal region during the 1972 summer upwelling season. The instruments used were the Webb-Voorhis vertical current meters which are freely drifting neutrally buoyant floats capable of sensing vertical motion. It was found that in the region studied, water tended to sink at depths of 40 to 60 meters under the influence of strong northward and southward winds but that water tended to rise during the slackening periods of a southward wind. Techniques used in processing the data, some problems encountered, and the results of four good dives are presented along with possible correlations of vertical water movements with wind, sea Level, and isopycnal movements. / Graduation date: 1974

Moored instrument records, drogue displacements, and hydrographic observations are used in describing the coastal currents and upwelling off Peru. The data were obtained over the continental shelf near 15°S. during a two week study in late March and early April of 1969. First order statistics and graphical representations of current meter time series indicate that the longshore flow was poleward during most of the study period, interrupted by a three day 'event' of equatorward flow. The similarity of flow at all current meters indicates that the field of flow as quasi-barotropic. The depth, extent, and transport of poleward flow indicated by current meter time series and geostrophic sections were similar to those described in the literature for the Peru-Chile Undercurrent. The observations suggest that this flow moved further offshore as equatorward flow appeared over the shelf. Power spectral analyses performed on current meter records indicate the existence of semidiurnal tidal currents in the longshore direction. The magnitude of these currents is estimated at 10% to 15% of period mean speeds. Ten meter drogue displacements are compared with 25 m recorded currents and with winds. The observations indicate that: the drogues were affected by both the 25 m flow and the wind; the depth of the wind drift layer was between 10 m and 25 m; the drogue displacements were in the sense expected from the Ekman model. Vertical sections of sigma-t, oxygen, and nitrate indicate the existence of conditions consistent with upwelling. Surface maps of temperature, nitrate, and chlorophyll 'a' over the shelf are used to define the horizontal field of upwelling and its variations in time. The distributions suggest that upwelling existed throughout the period and underwent temporal and spatial modulations in intensity. The possibility of a causal mechanism between observed current and upwelling variations is examined. Vertical salinity sections indicated the presence of a weak salinity minimum between the surface and 100 m. It is suggested that this minimum manifests the remnants of a tongue of Subantarctic Water embedded in a much larger mass of Equatorial Subsurface Water. The occurrence of the minimum only in conjunction with poleward flow suggests that the water was advected or mixed coastward somewhere north of the area studied, was entrained in the Peru-Chile Undercurrent, and was carried south again. / Graduation date: 1970

Graduation date: 1962

Graduation date: 1963

Nearly three months of current meter records from five moorings off the Oregon coast taken between October 1977 and January 1978 were analyzed for near-inertial motions. The moorings were located from the midshelf out to the foot of the continental slope, spanning the continental margin. All but two of the eleven current meters were continuously below the mixed layer. For spectral analysis, the current observation period was divided into two time periods, one with large amplitude near-inertial motion (41.1 cm/sec maximum of the band-passed records) throughout and the other with much less near-inertial energy. The spectra of the current meter records showed between a 1 and 6% increase in frequency of the near-inertial peak above f (= 0.0592 cph) in all but three cases. The exceptions showed spectral peaks about 14% below f and were linked to a Doppler shift. The period of large amplitude near-inertial motion had diagonal coherence scales of over 450 meters vertically and 115 kilometers horizontally. An east-west (cross-shelf) wavelength of about 50 kilometers was estimated directly from the phase differences between current meters with roughly horizontal separations. The observed response of a current meter about 35 meters below the mixed layer to sharp maxima in the wind stress was similar to that predicted by the Pollard and Millard (1970) model for wind forced near-inertial motions in the surface mixed layer. The winds associated with a series of atmospheric fronts were apparently responsible for generating a 14-day period of large amplitude near-inertial motion observed below the mixed layer. / Graduation date: 1982