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Paleomagnetism, magnetic properties and thermal history of a thick transitional-polarity lavaAudunsson, Haraldur 06 July 1989 (has links)
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
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The Role of Salmon in Middle Snake River Human Economy: The Hetrick Site in Regional ContextsManning, Cassandra R. 01 January 2011 (has links)
On the Columbia Plateau, the origin of the Winter Village Pattern has long been a focus of research. Intensification of resources such as salmon, roots, and local aquatic resources is often cited as the cause of declining mobility. To address this question in the middle Snake River region, I have re-analyzed fish remains from the Hetrick site (10WN469; Weiser, ID), with occupations spanning the Holocene. Expectations from foraging theory and paleoclimate data are used to address whether salmon and other fish use changed over time and if such changes are correlated with the development of the Winter Village Pattern. The results of my research indicate that there is no correlation between the timing of increased salmonid use at the Hetrick site and paleoclimatic change or the earliest evidence for the Winter Village Pattern. Further, these results are very similar to patterns of fish use seen at other sites on the Snake River, particularly those from the Early and Middle Holocene.
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Genesis of silica-enriched agricultural pans in soils managed under wheat-fallow cropping systemsAl-ismaily, Said S. 12 May 1997 (has links)
Graduation date: 1998
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Historic Structures Report: Lone Pine Indian Shaker Village, a Nineteenth Century Fishing Settlement in The Dalles, Wasco County, OregonSeaton, Anne 12 1900 (has links)
155 p. / Lone Pine Indian Shaker Village, located in The Dalles, Oregon, is the last remaining example of a late nineteenth century fishing settlement, a resource type that once proliferated along the banks of the Columbia River. Lone Pine Indian Shaker Village is also significant for its association with mixed heritage settlement, Native American fishing traditions, and the Indian Shaker Religion, a religion unique to the Northwest. This is an historical and architectural study of the village which includes the historical context and detailed description of the built environment, as it exists today and has evolved over time. Photographs, measured drawings, oral interviews and archival research are used to document and analyze the history and built environment of the village. Also included is a discussion of Treatment and Use options, followed by the author's recommendation for preservation and use of the village complex as an interpretive site. Today the village complex is vacant and suffers from neglect, and on November 19, 1996 the Indian Shaker Church collapsed under snow loads. Although an unfortunate event, it brings the issue of preservation of the entire site to the forefront. If no management plan is developed this valuable piece of Northwest cultural history will be lost forever. / Keepers of the Preservation Education Fund's H. Ward Jandl Fellowship
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Field sampling and mapping strategies for balancing nitrogen to variable soil water across landscapesRoberts, Michael C. (Michael Coy), 1951- 16 July 1991 (has links)
Graduation date: 1992
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Variability in late prehistoric prey-use strategies of the southeastern Columbia Plateau a test using the Harder Site faunal assemblage /Kimball, Vaughn R., January 2005 (has links) (PDF)
Thesis (M.A.)--Washington State University, 2005. / Title from PDF t.p. (viewed on Nov. 6, 2005). Includes bibliographical references (p. 75-84).
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