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The Geology, Geochemistry, and Alteration of Red Butte, Oregon: A Precious Metal-Bearing Paleo Hot Spring SystemEvans, Carol Susan 01 January 1986 (has links)
Red Butte is located 60 km south of Vale, Oregon, about 20 km west of the Oregon/Idaho border. The butte is within the Owyhee Upland physiographic province of eastern Oregon which lies at the intersection of the Western Snake River Plain, the High Lava Plains, and the Northern Basin and Range provinces.
The butte is composed of Miocene to Pliocene lacustrine and fluvial volcaniclastic sediments. The topography of the butte is controlled by silicification of the sandstones and mudstones which cap it. Silicification and hydrothermal alteration are both structurally and stratigraphically controlled. North-trending normal faults dominate the area, and show progressively less offset in younger units. Strong northwest and minor northeast faults also cut the area.
Anomalous concentrations of Au, As, Sb, and Hg occur in banded quartz, quartz-adularia veins and rarely in calcite-quartz veins cutting basalts. The silicified mudstones at the butte top are generally barren. An hydrothermal explosion crater exposed on the southeast side of the butte lies at the intersection of north and northwest-trending faults. Banded quartz veins, quartz-adularia veins, and quartz-cemented breccias are exposed in the walls of the explosion crater. There is evidence of multiple brecciation events. A few mudstones exposed in the crater wall have an exhalative texture, contain pyrite des seminated along bedding, and contain trace amounts of Au.
The Red Butte system developed as a hot spring venting into a lake, possibly within a caldera. Periodic influxes of air fall tuffs and coarser clastic sediments diluted accumulating fine grained clastic and chemical sediments. As hot, silica saturated fluids rose into cooler lake waters they were cooled and diluted, resulting in silica flocculation near the vents and silicification of the lake sediments as they were deposited. Faults cutting the butte acted as conduits for the hydrothermal fluids. Overpressuring, caused by silica sealing of open fractures, resulted in explosions, generally followed by resealing of the system. Simultaneous faulting, sedimentation, and hot spring activity occurred at different rates throughout the life of the system.
Late in the life of the system, the local water table dropped, and the lake was replaced by a high-energy fluvial system. As the water table dropped below the surface, zones of low pH alteration and bleaching were developed above the hydrothermal vents, implying boiling at depth.
The large explosion crater and bedded explosion breccia on the southeast side of the butte were formed in these last stages of hydrothermal activity.
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The effects of coypu Myocaster coypus (nutria) trapping on the water quality of South Johnson Creek, Beaverton, OregonFrankel, Deborah Jean 01 January 2007 (has links)
Nutria are semi-aquatic rodents, non-native to Oregon. They are an invasive species that damage stream banks with burrowing and cause destruction of native vegetation; activity that may cause deterioration of stream water quality. I hypothesized that my study's duration and pattern of nutria trapping along South Johnson Creek would be sufficient to lead to a significant change in turbidity, dissolved oxygen (DO), total dissolved solids (TDS), total solids (TS), and total suspended solids (TSS).
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Subsurface and geochemical stratigraphy of northwestern OregonLira, Olga Berenice 01 January 1990 (has links)
Lithological, geophysical, paleontological and geochemical methods were used in order to define the contact relationship between the Keasey and the Cowlitz formations in northwestern Oregon. Drill cuttings from six wells located in Columbia County were analyzed by the Instrumental Neutron Activation Analysis (INAA) method. The concentrations of K, Th, Rb and Sc/Co ratio in the samples established four different groups: 1) High K, Rb, and TH, with low Sc/Co ratio typical of Cowlitz sediments. 2) Low K, Th and Rb and high Sc/Co ratio, more characteristics of the Keasey Formation. 3) Very low concentrations of Rb and high Sc, which is indicative of basaltic volcanism. 4) vertically varying K, Th and Rb concentrations. The provenance of group four is uncertain, but it may represent reworked sediments or the interfingering of the Keasey and the Cowlitz formations. Plots of these elements vs. depth define the geochemical contacts between the formations.
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At the Trail's EndMarshall, Naomi 11 January 2018 (has links)
Oregon City lies at the base of Willamette Falls. It was one of the few known points in the Oregon Territory, as the destination for thousands coming overland to lay claim to the acres upon acres of forested land. Presently, Oregon City is known by its proximity to Portland. The two neighboring settlements were considered "long-distance," when on a spring evening in 1889, energy generated from the falls was carried through 14 miles of recently-laid copper wire to power streetlights in downtown Portland's Chapman Square. It was the first ever long-distance transmission of electricity. Oregon City, the oldest incorporated settlement west of the Rocky Mountains, is a town in transition, as it attempts to reinvent itself as something more than an old mill town, building on its natural beauty and historical significance.
This essay collection showcases the history and character of Oregon City, highlighting the people and places that have called it home.
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A reinterpretation of the Oregon school bill of 1922 : the concept of the common school in progressive America.Recken, Stephen Louis 01 January 1973 (has links)
The Oregon School Bill of 1922 would have required all school age children to attend public schools. Beginning as an initiative measure sponsored by the Scottish Rite Masons it was passed by the voters in the general election in the Fall of 1922. Shortly after its passage representatives of private and parochial schools began a court battle against the bill which ended in the United States Supreme Court. Affirming the decision of a lower court it declared the Bill to be unconstitutional. While public interest in the Bill was great during the campaign, it soon dwindled and by 1925 the School Bill held little interest but to historians.
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Relationships between Avian Diversity and Vegetational Parameters in Forested Patches of the Tualatin Mountains, OregonFugate, Jerry Sexton 27 April 1994 (has links)
The effect of contiguous forested habitat area on local avian diversity and species richness in the Tualatin Mountain area of northwestern Oregon was investigated. Observations of eight forested stands representing seven area values (1, 2, 7, 14, 18, 24 and 40 hectares) were made during the spring and summer of 1991 and 1992. The variables measured were chosen in an attempt to show possible relationships between vegetation factors, spatial patterns and bird communities. Kendall's rank correlation coefficients were used to analyze the data. Avian species richness and diversity were significantly correlated with forest stand (patch) size. The only significant correlation between avian species richness and diversity and vegetation measures was with percent shrub layer cover. It seems likely that avian diversity and richness are increased due to the presence of species that can utilize the interior and edges of forest stands along with species which depend upon true forested interior. When forested patch size drops below a critical area, the patch becomes all edge. Interior species are absent due to increased predation and the inability to compete with interior-edge species. Edge effect may be a contributing factor to variation in diversity of birds. The correlation of percent shrub layer cover with avian measures is accompanied by a correlation of percent shrub layer cover with distance from edge. This suggests further investigation is required to assess this relationship. Studies conducted in the northeastern and north central United States have shown a similar relationship between bird communities and forest patch size.
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Cognitive Development of Bilingual Korean-Americans in an Oregon School DistrictKing, Kimiko Okada 05 February 1993 (has links)
This research examined whether bilingualism would accelerate or hinder the cognitive as well as academic development of the Korean American individuals in an Oregon school district by analyzing the standardized test scores at grades 3, 5, 7, and 9. Eleven monolingual and 27 bilingual students released the Survey of Basic Skills (SBS) as well as Cognitive Abilities Test (CogAT) scores for this study. The analyses of the test scores revealed that the Korean-American students in this school district were performing at a much higher level against the national norm (the 50th percentile), or the school district norm (the 75th percentile). The bilingual Korean-American students made far greater progress both cognitively and academically from grades 3 to 9 (CogAT: 76.0 %ILE- 87.0 %ILE, SBS Composite: 77.0 %ILE- 87.0 %ILE) than their monolingual counterparts who hovered around the 85th percentile against the national norm. It was learned that the bilingual Korean-Americans were both cognitively and academically as developed as their monolingual counterparts by the time they were in 5th grade. Telephone interviews conducted with 46 bilingual and 23 monolingual Korean-American high school students as well as 30 written questionnaires returned by their parents revealed that the Korean-American students in this particular school district could not become naturally bilingual, but that a commitment both by the students and their parents was necessary to maintain their ethnic language. The parents of the bilingual students were making more efforts to pass on the Korean language to their offspring than the parents of monolingual students. The Korean-American families were very much integrated into the social mainstream, and were trying to achieve educational as well as economic successes on American's terms while maintaining their ethnic identity.
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Regeneration Patterns and Facilitation Following Blowdown in a Self- Replacing Lodgepole Pine (Pinus contorta) Stand in Central OregonKarps, Jennifer Michelle 16 February 2006 (has links)
Nurse plant and object facilitation is an important factor mitigating abiotic stress, improving seedling recruitment, and shaping the fine-scale spatial patterns of many plant communities. I investigate the role of facilitation on lodgepole pine regeneration following blowdown in central Oregon. My objective is to examine the importance of nurse objects on seedling recruitment under varying stand conditions. I base my analysis on 1) the mapped locations and attributes of seedlings, saplings, trees, shrubs, snags, stumps, and sound and decomposed logs in each of five, 500 m2 circular plots, 2) water holding capacity estimates of woody and leafy litter and pumice soil, and 3) growing-season air temperatures. My analysis identifies seedling patterns at multiple spatial scales (~0-8 m) using nearest neighbor and Ripley’s K statistics and identifies differences in canopy structure, seedling development, and temperature using non-parametric rank-sum tests.
My results show blowdown severity varies with pre-disturbance stand structure, resulting in a multi-modal stand structure with a wide range of canopy and seedling microhabitat conditions. Stand-wide, post-blowdown regeneration patterns reveal >80% of seedlings grow near nurse shrubs, logs, and woody litter, suggesting preferential germination and survival in these microhabitats. High seedling densities correspond with median shrub diameters, and up to 38% of seedlings grow near recently downed logs, indicating both shrubs and logs serve as important nurse objects. The role of nurse objects in mitigating moisture stress is implicated by the potentially high evaporative stress under extreme growing season temperatures in areas of severe blowdown and by the high moisture-holding capacity of woody litter relative to the pumice soil. Stand-wide, 91% of all seedlings and 87% of all shrubs grow on woody litter, and seedlings growing on woody litter show the greatest development.
The positive spatial correlation of seedlings and shrubs with nurse plants and woody litter supports the assertion that both are important facilitators for seedling regeneration and emerging spatial patterns of stand recovery. These results have important management implications, suggesting that the removal of nurse plants and objects through salvage logging or prescribed burning may have negative long-term impacts on local and regional forest regeneration.
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Acculturation and food : a study of Vietnamese women in Portland, OregonSarasin, Heather M. 15 April 2004 (has links)
This study is intended to provide information about the situation of first-generation
Vietnamese women to the IRCO Parent and Child Program Department in Portland,
Oregon. Nutrition intervention and food assistance currently offered to Vietnamese
women enrolled in this program is the focus of the study. The women interviewed
characterize themselves and their eating patterns as Vietnamese, though many changes in
practice and concept reflect those of American culture. The study reveals several
categories of food acculturation that act both separately and influence the development of
each other. These categories are diet, taste, solutions, and concepts. Recommendations
are made according to the categories and process of acculturation demonstrated by the
participating women and the effects of this process on the health of the women and their
families. / Graduation date: 2004
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Cooperation and small to medium sized enterprises in Oregon's forest product industryBrown, Nicole A. 09 February 2004 (has links)
This thesis examines perceptions of cooperation among small to medium sized
enterprises (SME) in western Oregon's forest products industry. Recent changes in the
industry, such as corporate consolidation, global marketing, and government regulations
have created an environment in which many SMEs find it difficult to stay competitive.
Cooperation among SMEs is one method for alleviating the situation; however, few SME
owners are engaging in cooperative projects or behaviors.
Common assumptions and stereotypes about the individualistic nature of the
forest products industry lead some to believe that cooperation is an unlikely avenue for
SME owners. Through 16 in-depth interviews with SME owners, this view is found to be
overly simplistic. It does not account for the variety of factors at play and the depth of
the issues involved in SME owners' attitudes toward cooperation. In studying attitudes
toward cooperation, this study first attempts to understand the cultural values of the
decision makers. It is apparent that values play an integral role in the decision making
and strategy of SME owners.
This research highlights the complexity of the issues facing small businesses and
their owners and reveals that four main factors contribute to SME owners' perceptions
about cooperation and influence strategic business decisions: common values,
stereotypes, risk perception, and a lack of knowledge about cooperation. Values are
found to be especially relevant in understanding and influencing attitudes toward
cooperation as values affect risk perception and risk perception in turn directly impacts
business strategy. Understanding the values of SME owners helps to describe their attitudes toward cooperation and dispels the notion that they are too independent to ever
work together.
Eight recommendations stem from the findings of this study which may lead to
cooperative action and more successful SMEs: 1) Find a trustworthy agent to act as a
sponsor; 2) Build credible systems; 3) Match members with similar values; 4) Expound
the potential benefits of cooperation to reduce risk perception; 5) Find a spark plug, not a
spokesperson; 6) Provide education; 7) Define and implement both learning networks and
action groups; 8) Target new and future categories of SME owners such as women and
the children or grandchildren of current owners. / Graduation date: 2004
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