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Acoustic monitoring of earthquakes along the Blanco Transform Fault Zone and Gorda plate and their tectonic implicationsDziak, Robert P. 02 June 1997 (has links)
Hydroacoustic tertiary (T-) waves are seismically generated acoustic waves that propagate
over great distances in the ocean sound channel with little loss in signal strength.
Hydrophone recorded T-waves can provide a lower earthquake detection threshold and an
improved epicenter location accuracy for oceanic earthquakes than land-based seismic
networks. Thus detection and location of NE Pacific ocean earthquakes along the Blanco
Transform Fault (BTFZ) and Gorda plate using the U.S. Navy's SOSUS (SOund
SUrveillance System) hydrophone arrays afford greater insight into the current state of
stress and crustal deformation mechanics than previously available. Acoustic earthquake
information combined with bathymetry, submersible observations, earthquake source-parameter
estimates, petrologic samples, and water-column chemistry renders a new
tectonic view of the southern Juan de Fuca plate boundaries.
Chapter 2 discusses development of seismo-acoustic analysis techniques using the
well-documented April 1992 Cape Mendocino earthquake sequence. Findings include a
hydrophone detection threshold estimate (M~2.4), and T-wave propagation path modeling
to approximate earthquake acoustic source energy. Empirical analyses indicate that
acoustic energy provides a reasonable magnitude and seismic moment estimate of oceanic
earthquakes not detected by seismic networks. Chapters 3 documents a probable volcanogenic T-wave event swarm along a pull-apart basin within the western BTFZ during January 1994. Response efforts yielded evidence of anomalous water-column ��He concentrations, pillow-lava volcanism, and the first discovery of active hydrothermal vents along an oceanic fracture zone. Chapter 4 discusses the detection of a NE-SW trending microearthquake band along the mid-Gorda plate which was active from initiation of SOSUS recording in August 1991 through July 1992, then abruptly ceased. It is proposed that eventual termination of the Gorda plate seismicity band is due to strain reduction associated with the Cape Mendocino earthquake sequence. Chapter 5 combines bathymetric, hydro-acoustic, seismic, submersible, and gravity data to investigate the active tectonics of the transform parallel Blanco Ridge (BR), along the eastern BTFZ. The BR formation mechanism preferred here is uplift through strike-slip motion (with a normal component) followed by formation and intrusion of mantle-derived serpentinized-peridotite into the shallow ocean crust. The conclusion considers a potential link between the deformation patterns observed along the BTFZ and Gorda plate regions. / Graduation date: 1998
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Genetic variability for kernel hardness in two soft winter wheat (Triticum aestivum L.) cultivatorsAlbahouh, Muhammed S. 15 April 1992 (has links)
To remain competitive in the international marketplace,
soft white wheat cultivars grown in the Pacific Northwest
must have consistent and predictable flour properties
including kernel texture. As a consequence, there is a need
to develop wheat cultivars for specific end uses. Wheat
cultivars with very soft kernels are used largely for making
cookies and cakes. Harder soft white wheats are more
suitable for noodles and flat breads. Numerous studies have
been made to determine the inheritance of kernel texture
between hard and soft wheat; however, very little
information is available concerning the amount of genetic
variability within soft white wheat.
Reciprocal crosses were made between a very soft
(TJB/MON"S") and a soft (Yamhill) white winter wheat
genotype. Data were collected on an individual plant basis
for kernel texture, protein content, and eight selected
agronomic traits. Kernel hardness and protein content were
determined using the near-infrared reflectance spectroscopy
(NIR).
Genetic differences for kernel texture and the other
nine traits were found between the two parents and the
resulting F1 progenies. It would appear that kernel texture
is qualitatively inherited with one or more genes reflecting
additive and nonadditive gene action. However, a large
component of non-genetic variation was also detected.
Of particular interest was the apparent reciprocal
differences found between Fl populations for most of the
traits measured and particularly kernel texture. However,
for kernel texture, such differences were not due to a
dosage effect of the 3n endosperm.
Kernel texture was not found to be associated with
protein content. A negative association of kernel texture
with heading date would suggest a compromise may be
necessary when selecting these traits. Positive associations
were found between kernel hardness with number of tillers,
total biological yield, grain yield, and number of kernels
per spike. / Graduation date: 1992
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Systematic and reproductive studies of Mimulus (Scrophulariaceae) in the Pacific Northwest : implications for conservation biologyMeinke, Robert James 08 May 1992 (has links)
The Mimulus washingtonensis complex is a group of morphologically similar
species centered in the Pacific Northwest. All are rare, and most are under
consideration for listing as endangered. Morphometric and pollination data were
used in developing a revised taxonomy for the group. Five species and two varieties
are recognized. Mimulus pulsiferae Gray is the most widespread, occurring from
southern Washington to northern California. Mimulus hymenophyllus Meinke and
M. jungermannioides Suksd. are cliff species endemic to river drainages in northern
Oregon. Mimulus washingtonensis Gand. occurs in east-central Oregon and western
Idaho, represented by the var. washingtonensis and var. ampliatus (Grant) Meinke
comb. et stat. nov., respectively. Mimulus patulus Pennell is resurrected from
synonymy and differentiated from M. washingtonensis on the basis of morphology,
distribution, and pollination biology. This autogamous species includes var. patulus,
occurring in the Snake River drainage, and var. montanus Meinke var. nov.,
primarily from the northern Rocky Mountains.
Mimulus evanescens Meinke sp. nov. is described from an extant population
in Lassen County, California, and historic collections from widely scattered stations
in Oregon and Idaho. The new species is morphologically intermediate between M.
breviflorus Piper and M. latidens (Gray) Greene. Calyx and leaf morphology also
suggest an affinity to M. grayi Grant, M. inconspicuus Gray, and M. acutidens
Greene, of cismontane California. Mimulus evanescens should be considered
critically endangered, because of its limited numbers and habitat degradation.
Mimulus washingtonensis is pollinated by small native bees, primarily two
species of Dialictus (Halictidae). These bees were specific to Mimulus flowers but
did not distinguish between flowers of M. washingtonensis and M. guttatus DC., a
related species that increases with habitat disturbance. Experiments showed that
mixed pollen loads diminish seed set in M. washingtonensis, since the thigmotropic
stigma of that species closes permanently after any amount of conspecific pollen is
applied. Although M. washingtonensis has a low pollen/ovule ratio (29.9), it is
considered facultatively xenogamous based on floral morphology, stigma sensitivity,
and autogamous seed set levels. Populations occurred in small, edaphically
restricted patches, and they exhibited seed set reductions related to outcrossing
distance. Substrate disturbance may limit reproduction in M. washingtonensis by
changing population structure, threatening pollinators, and increasing competition for
pollination by promoting growth and flowering of M. guttatus. / Graduation date: 1992
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A comparative analysis of stream response to disturbance in the Pacific NorthwestHodgins-Carlson, Terry Anne 12 January 1993 (has links)
Published literature about six Pacific Northwest stream systems was contrasted
to provide a regional perspective on channel response to disturbance. This
investigation was prompted by a combination of recent environmental legislation,
mounting social pressures to plan projects at a drainage basin scale, and the difficulty
in defining and predicting the response and recovery of a stream channel to land-use
management or storm events.
Detailed studies of Redwood Creek, CA; the San Lorenzo River, CA; the South
Fork Salmon River, ID; the Upper Middle Fork of the Willamette River, OR; the Alsea
River System, OR; and Carnation Creek, B.C. were reviewed and contrasted.
Differences in channel response to disturbance appear to be the result of the sequence
of storms, the interactions between storms and land-use, the processes that deliver
sediment to the channel, the available stream power, and the bank stability. Basins
with low debris avalanche and earthflow potential, high stream power, and stable
stream banks experience only localized and short-lived response to disturbance. On
the other hand, basins with frequent debris avalanches or high earthflow potential and
unstable banks experience widespread and persistent response.
This study concludes that there must be realization and acceptance of the
random nature of channel response and recovery following disturbance. Field
evaluation, professional judgement, risk assessment, and adaptive management are
the most powerful tools available in the prediction of channel response. / Graduation date: 1993
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Response to Hypoxia in the staghorn sculpin, (Leptocottus armatus)Wagner, Sara Anne 02 November 1990 (has links)
Long-term subae lal survival has been anecdotally noted
in the staghorn sculpin, Leptocottus armatus. In this study,
I quantified this phenomenon physiologically by examining the
following parameters: standard metabolic rate and indications
of reduced standard metabolic rate during subaerial exposure;
capacity for and mechanism(s) of oxygen consumption in air;
capacity for anaerobic production of lactate and/or ethanol;
and blood pH. The staghorn sculpin appears well-suited for
the subaerial exposure it experiences in nature. Mean
subaerial survival time was 6 hours which would enable fish to
survive intertidal stranding. Staghorns breathe air through
well-supported gills and supplement depressed rates of
subaerial aerobiosis by anaerobic production of lactic acid.
Most remarkably, the staghorn sculpin may also substantially
reduce minimal energy expenditure requirements during periods
of hypoxia by reducing resting metabolic rate. / Graduation date: 1991
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Trophic feedback and carrying capacity of Pacific salmon (Oncorhynchus spp.) on the high seas of the Gulf of Alaska /Aydin, Kerim Yunus. January 2000 (has links)
Thesis (Ph. D.)--University of Washington, 2000. / Vita. Includes bibliographical references (leaves 364-378).
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The effect of drought stress on the chemical composition and distribution in Russet Burbank and AO82260-8 potatoesZhang, Peifang 07 July 1989 (has links)
The effects of early season and late season drought stress on
various carbohydrates, calcium and/or nitrogen content at apical,
central and basal tuber locations were studied for Russet Burbank
and A082260-8 potatoes. Drought stress which occurred early in the
stage of tuber development appeared to have more detrimental effect
than later season stress. Interactions between treatment and
sampling date and variety x position x date were significant during
early season stress.
Generally, percent total solids increased during potato
development for both varieties. The central portion of tuber had
the lowest total solids.
Total reducing sugar content generally decreased during potato
development for both varieties with significant (P<.05) differences
at early season stress due to the interaction effects of treatment
x date and variety x position. No significant difference in
reducing sugar at later season stress was found regardless of treatment. Variety difference in reducing sugar content occurred
at the apical end. Russet Burbank had more reducing sugars than
A082260-8 at this end. The exploration of fructose, glucose and
sucrose individually showed the same developing pattern as total
reducing sugar. Sucrose made up over 50% of the total sugars with
glucose and fructose the next in order of importance. The apical
end had more sucrose and glucose than the basal end.
The interaction of variety and position for both nitrogen and
dietary fiber may be a result of growth pattern differences in the
two treatments. Total dietary fiber content was generally the
highest at the basal portion for both varieties. Russet Burbank
appeared to have higher total dietary fiber than A082260-8 at this
end. The level of calcium in Russet Burbank was significantly
higher than that in A082260-8. Basal and apical portions had
higher calcium content than the central portion. / Graduation date: 1990
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Radiolarian microfauna in the northern California current system : spatial and temporal variability and implications for paleoceanographic reconstructionsWelling, Leigh A. 19 November 1990 (has links)
Graduation date: 1991
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Millennial-scale surface and deep water oscillations in the N.E. Pacific : implications for late pleistocene climate changeLund, David Charles 30 October 1997 (has links)
Graduation date: 1998
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Seamount paleomagnetism and Pacific plate tectonicsSager, W. W (William W.) January 1983 (has links)
Typescript. / Thesis (Ph. D.)--University of Hawaii at Manoa, 1983. / Bibliography: leaves 441-472. / Microfiche. / xvii, 472 leaves, bound ill., maps 29 cm
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