The nearshore zone at Newport, Oregon was studied during the
period September, 1968 to August, 1969. Particular emphasis was
placed on those physical factors affecting the distribution of pulp mill
wastes discharged within the study area (referred to as Yaquina Bight
in this thesis). Temperatures and seawater samples were obtained...
The concentrations of calcite, opal and quartz have been measured in 113 South Atlantic core tops. The remainder of the total sample has been calculated as clay. A method for the quantitative determination of opal has been developed.
Calcite is the dominant factor in South Atlantic sediments; its pattern can...
This study was conducted to determine the composition and size of prey consumed by northern fur seals (Callorhinus ursinus) in the eastern Bering Sea. Eighty three northern fur seals were collected in the summer and fall of 1981, 1982, and 1985 for examination of gastrointestinal contents. A total of 139...
Beach response to overwash processes is a topic of significant importance. Two
particular aspects of this topic were chosen for detailed analysis: the distribution of
maximum wave runup elevations and the cross-beach celerity gradient of overwash bores
on natural beaches. Data were collected using both traditional nearshore instrumentation
and recently...
The Columbia River Estuary was sampled during high (May-June), intermediate (July), and low (September-October) river flow seasons to further define the role of the ETM with respect to its effect on primary biomass and production, and to discover how this effect changes in space and time.
Strong ETMs were determined...
Complete larval histories, consisting of a prezoeal stage, two
zoeal stages and one megalopal stage,are described for four species
of porcellanid anomurans. Larvae of three species were reared
from embryos through the megalopa stage in the laboratory. Larvae
of the fourth species were collected from the plankton and reared to...
Bimonthly plankton samples were collected from 1969 through
1971 along a transect off the central Oregon continental shelf (44°
39. l'N) to document the species of crab larvae present, their seasonality,
and their onshore-offshore distribution in relation to seasonal
changes in oceanographic conditions. A comprehensive key with
plates is given...
A study of sedimentary structures and sediment texture of
beach and continental shelf sediments provides a basis for the interpretation
of the recent history of sedimentation on the Oregon continental
shelf. The texture of various sediment types suggests that
coastal rivers supply a considerable quantity of very fine sand in...
Adula californiensis, which inhabits mudstone along the open
coast and in Yaquina Bay, Oregon, is subjected to extremely varying
conditions. Laboratory experiments of a factorial design were used
to investigate the effects of temperature and salinity on survival,
growth and respiration during early development.
The rate of development to the...
Growth and reproductive patterns of the common lanternfish,
Stenobrachius leucopsarus, are described by length frequency
analysis, otolith analysis and examination of ovaries.
Length frequency analysis, employing the probability paper
method of analysis of polymodal distributions, of three and one-half
years of monthly midwater trawl collections off Oregon showed that
fish...
The assumption of constant quartz accumulation for the deep-sea
sediment core Y69-106P, taken in the Panama Basin, has been
used to date the core and construct a sedimentation rate versus time
curve for it. Stratigraphic control for the calculated time scale
includes three carbon-14 measurements, the extinction of the
radiolarian...
Factor analysis of radiolarian species from the tops of 34 gravity
cores in the area extending from 5°N to 45°N, 95°W to 155°W, yields
five factor assemblages which are related to the present surface circulation:
1) a Pacific Equatorial Water assemblage; 2) a California
Current assemblage; 3) a North Equatorial...
An analysis of the amounts of calcium carbonate, organic carbon,
quartz, and the rates of sediment accumulation in hemipelagic sediments
off Oregon has revealed that the accumulation rates of the total
sediment, organic carbon, and quartz were at least twice as high in
the late Pleistocene as they were during...
Three realms of deposition, Marine, Fluviatile, and Marine-
Fluviatile, are recognized in Yaquina Bay, Oregon, on the basis of
sediment texture and mineralogy. The Marine Realm extends 1.5
miles into the entrance of the estuary and is typified by normal
marine salinity and vigorous tidal action. Sediments of this realm...
Sea-cliff erosion is a significant problem along the Oregon coast in that many
communities have been built on terraces affected by bluff retreat. There is considerable
coast-wide variability in the rates of cliff erosion. This variability is attributed in part to
tectonic activity that is causing differential interseismic uplift along...
Zooplankton samples taken during daylight periods in a fast flushing estuary on the Central Oregon coast were analyzed for Brachyuran and Anomuran larvae and also for benthic gammaridean amphipods and Myscidacea. Several larval stages of Pinnixa littoralis, Hemigrapsus oregonensis, Pachycheles spp., Cancer oregonensis and Pagurus granosimanus were sufficiently abundant for...
During the Callianassa californiensis larval release period, weekly zooplankton samples were taken through daylight tidal cycles near the mouth of a small, fast flushing estuary on the Central Oregon coast. Although C. californiensis adults are confined to estuaries and embayments, stage I zoeal larvae were shown to be exported from...
During the last 15 years, numerous geophysical surveys and geological sampling and coring expeditions have helped to characterize the tectonic setting, subsurface stratigraphy, and gas hydrate occurrence and abundance within the region of the accretionary wedge surrounding Hydrate Ridge. Because of these investigations, Hydrate Ridge has developed as an international...
Solid phases that form under the influence of changing environmental conditions often record such changes in their chemical composition. Quantification of these compositional variations is invaluable in reconstructing paleoenvironmental changes. Laser ablation, employed as a solid sample introduction system, offers fine spatial resolution (50 - 250 [mu]m) for spectroscopic analysis...
The physical linkage between oceanic earthquakes and most
tsunamis is generally accepted. The commonly offered method of
generation of a tsunami calls for displacement of submarine blocks
of the earth's crust. But, the mechanism of communication of seismic
energy to the water by the impulsive movements of the sea floor...
The migrations, distribution, and feeding of American shad, Alosa
sapidissima (Wilson), were studied from February 1980 through January
1981 in the Columbia River Estuary, an important rearing zone for
young-of-the-year shad. Sampling was performed with purse seine,
beach seine, and otter trawl.
Adult shad and large numbers of juveniles from...
We sharpen our view of an eastern boundary current region during
the upwelling season through the analysis of several data sets.
We focus on the mesoscale flow field off of northern California,
observed during the Coastal Transition Zone (CTZ) experiment of 1988.
First, we estimate tidal currents in the region...
Plankton and surface sediment samples from the Gulf of California
were analyzed to determine the present geographic distribution of silicoflagellate
species in this area. Variations in the composition of the
silicoflagellate assemblage are related to water mass distributions.
Seven species and three forms were identified in these samples. Octactis
pulchra...
Number of harbor seals, counted on 32 haul-out areas in Oregon, increased by 6 - 8.8 % per year from 1975 - 1983. Percent of seals in bays has increased an average 1.8%/year, from 47% in 1975 to 61% in 1983. Along the central Oregon coast, harbor seals were most...
Northern sea lions (Eumetopias lubatus) were studied at three sites (Rogue Reef, Oregon, Marmot Island, Alaska, and T.Ugamak Island,
Alaska) during the 1982, 1983, 1985, and 1986 breeding seasons. Data were collected on female activity budgets, attendance patterns, births, copulations, population structure, and patterns of seasonal and daily abundance. Females...
The extent and mechanism of energy dissipation has been studied in Coos Bay, a coastal plain estuary. Coos Bay is located on the central Oregon coast, 184 nautical
miles south of Astoria, Oregon, and 35 nautical miles north of Cape Blanco. Past field work in Coos Bay and data obtained...
The Antarctic Ocean during the Cenozoic experienced four periods of increased surface productivity: the Middle Eocene; the beginning of the Miocene; the Middle Miocene; and near the Miocene-Pliocene boundary. The fourth increase in productivity began five
million years ago and has since progressively increased to the present level of intense...
The claw shuddering display of the shore crab Hemigrapsus oregonensis was explored with acoustic and behavioral observations. Male H.
oreqonensis stridulate during claw shuddering display. The stridulatory apparatus is present only on the males. The acoustic signal was of brief duration, showed a general pattern of sound bursts, but varied...
Based on the principle that the history of a discipline is important to the discipline itself, this thesis devotes two chapters to ROBERT HOOKE AND THE FOUNDATION OF GEOLOGY and two chapters to modern geology, viz. THE TECTONIC EVOLUTION OF THE OREGON CONTINENTAL MARGIN. The first part of this abstract...
Netarts Bay is a coastal lagoon on the northern Oregon coast. Four major sedimentary environments are recognized including channel, sand flats, mud flats, and marsh. Fine-grained sediment is carried in by streams and deposited in the marshes and mud flats. Fine sand for the channel and sand flats is derived...
Field and laboratory work was undertaken in 1993 to increase understanding of the life history and ecology of the brown jellyfish,
Chrysaora fuscescens, a large semaeostome typically abundant in the neritic regions of the Oregon coast during summer months. Few
medusae were found during 1993, possibly the result of anomalous...
Past studies of the Oregon and Washington coast have shown a rapid change in the coastal ocean conditions with the onset of upwelling in spring. This process, called the spring transition marks the change from winter to summer conditions along the west coast of Unites States. To examine the interannual...
An investigation has been made of several physical parameters of the effluent plume of the Columbia River as it enters the Pacific
Ocean. Radioactive material in trace amounts enters the Columbia River from the Hanford nuclear reactors at Richland, Washington. One of these nuclides, chromium -51, has been used to...
Euphausiids constituted the major food of five co-occuring species of rockfishes (Sebastes spp.). Copepods, decapods, cephalopods, amphipods, fishes and other pelagic prey were also consumed but were
less important to the overall diet. Two species, S. flavidus and S. diploproa, were relatively euryphagous, utilizing a high number of prey taxa....
A series of factorial experiments were conducted using eyed oyster larvae (Crassostrea gigas) reared at a commercial hatchery in Netarts, Oregon. The objectives of the study were to obtain the highest percentage of setting larvae and the best survival of the spat. Experiments on the combined effects of temperature and...
The copepod population in Oregon coastal waters was examined from 116 oblique plankton tows taken during 1962. Quantitative Clarke-
Bumpus samplers were used and stations ranged from 5-105 miles from shore along four hydrographic lines. Forty-six species of copepods were identified. The total adult population varied according to distance from...
Fifty-two one-meter plankton net samples from four stations off Newport, Oregon, were examined for composition and abundance of euphausiids and copepods. They provided data on dominance, species associations and environmental relationships. The euphausiid-copepod population off Oregon is composed of 12 numerically dominant species. These species occurred in most of the...
This thesis investigates the behavior of major inorganic nutrients (P, N, Si), trace metals (Mn, Fe), and alkaline-earth metals (Ba) within Tillamook Bay over seasonal cycles and under a range of river discharge conditions from October 1997 through December 1999. Located in the Pacific Northwest region, Tillamook Bay is an...
The Oregon continental shelf waters are typically characterized by four to five major upwelling events that occur between May and October. The upwelled water is rich in nutrients, which fuels an increase in phytoplankton biomass. The onset of El Nino, however, can disrupt the normal physical processes along the Oregon...
Inner-shelf circulation and mechanisms of across-shelf transport of water masses were examined using seven years of observations collected by the Partnership for Interdisciplinary Studies of Coastal Oceans (PISCO) program, a long-term monitoring effort along the central Oregon coast. Since 1998, moored velocity and hydrographic measurements have been obtained during the...
An empirical statistical model is developed that relates the non-tidal motion of the ocean surface currents off the Oregon coast to forecasts of the coastal winds. The empirical statistical model is then used to produce predictions of the surface currents that are evaluated for their agreement with measured currents. Measurements...