Relevant bibliographies by topics / Geochemistry – Oregon – Willamette River Valley

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  2. Dissertations / Theses
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Academic literature on the topic 'Geochemistry – Oregon – Willamette River Valley'

Author: Grafiati
Published: 4 June 2021
Last updated: 3 February 2022

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Journal articles on the topic "Geochemistry – Oregon – Willamette River Valley"

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Liberty, Lee M., Anne M. Trehu, Richard J. Blakely, and Martin E. Dougherty. "Integration of high-resolution seismic and aeromagnetic data for earthquake hazards evaluations: An example from the Willamette Valley, Oregon." Bulletin of the Seismological Society of America 89, no. 6 (December 1, 1999): 1473–83. http://dx.doi.org/10.1785/bssa0890061473.

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Abstract Aeromagnetic and high-resolution seismic reflection data were integrated to place constraints on the history of seismic activity and to determine the continuity of the possibly active, yet largely concealed Mount Angel fault in the Willamette Valley, Oregon. Recent seismic activity possibly related to the 20-km-long fault includes a swarm of small earthquakes near Woodburn in 1990 and the magnitude 5.6 Scotts Mills earthquake in 1993. Newly acquired aeromagnetic data show several large northwest-trending anomalies, including one associated with the Mount Angel fault. The magnetic signature indicates that the fault may actually extend 70 km across the Willamette Valley to join the Newberg and Gales Creek faults in the Oregon Coast Range. We collected 24-fold high-resolution seismic reflection data along two transects near Woodburn, Oregon, to image the offset of the Miocene-age Columbia River Basalts (CRB) and overlying sediments at and northwest of the known mapped extent of the Mount Angel fault. The seismic data show a 100-200-m offset in the CRB reflector at depths from 300 to 700 m. Folded or offset sediments appear above the CRB with decreasing amplitude to depths as shallow as were imaged (approximately 40 m). Modeling experiments based on the magnetic data indicate, however, that the anomaly associated with the Mount Angel fault is not caused solely by an offset of the CRB and overlying sediments. Underlying magnetic sources, which we presume to be volcanic rocks of the Siletz terrane, must have vertical offsets of at least 500 m to fit the observed data. We conclude that the Mount Angel fault appears to have been active since Eocene age and that the Gales Creek, Newberg, and Mount Angel faults should be considered a single potentially active fault system. This fault, as well as other parallel northwest-trending faults in the Willamette Valley, should be considered as risks for future potentially damaging earthquakes.
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Follett, P. A., B. A. Croft, and P. H. Westigard. "REGIONAL RESISTANCE TO INSECTICIDES IN PSYLLA PYRICOLA FROM PEAR ORCHARDS IN OREGON." Canadian Entomologist 117, no. 5 (May 1985): 565–73. http://dx.doi.org/10.4039/ent117565-5.

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AbstractUsing a slide-dip bioassay, Psylla pyricola Forester from intensively sprayed, minimally sprayed (IPM), recently abandoned, and long-abandoned pear orchards in the Hood River, Rogue River, and Willamette valleys of Oregon were surveyed for resistances to azinphosmethyl, endosulfan, Perthane®, and fenvalerate. Lethal-concentration (LC50) values showed resistance levels from 12- to 41-fold to azinphosmethyl and 5- to 12-fold for endosulfan in selected populations. Resistance patterns did not correlate with orchard-treatment histories in the Hood River and Rogue River valleys, where even long-abandoned orchards harbored resistance psylla. There was better association between treatment histories and resistance levels in populations from the more widely scattered orchards in the Willamette Valley. A regional analysis of mean LC50 values indicated that psylla resistance was significantly higher to azinphosmethyl in the Rogue River Valley and to endosulfan in the Hood River Valley. Regional resistance levels for these compounds reflect differences in intensity of past use. A regional hypothesis is proposed to explain the patterns of resistance developed in the Hood River and Rogue River Valleys, where pear production is intensive as opposed to the more localized patterns of resistance in the Willamette Valley. Applications of results to the management of resistance are discussed.
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Strimbu, Bogdan M., George Mueller-Warrant, and Kristin Trippe. "Agricultural Crop Change in the Willamette Valley, Oregon, from 2004 to 2017." Data 6, no. 2 (February 7, 2021): 17. http://dx.doi.org/10.3390/data6020017.

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The Willamette Valley, bounded to the west by the Coast Range and to the east by the Cascade Mountains, is the largest river valley completely confined to Oregon. The fertile valley soils combined with a temperate, marine climate create ideal agronomic conditions for seed production. Historically, seed cropping systems in the Willamette Valley have focused on the production of grass and forage seeds. In addition to growing over two-thirds of the nation’s cool-season grass seed, cropping systems in the Willamette Valley include a diverse rotation of over 250 commodities for forage, seed, food, and cover cropping applications. Tracking the sequence of crop rotations that are grown in the Willamette Valley is paramount to answering a broad spectrum of agronomic, environmental, and economical questions. Landsat imagery covering approximately 25,303 km2 were used to identify agricultural crops in production from 2004 to 2017. The agricultural crops were distinguished by classifying images primarily acquired by three platforms: Landsat 5 (2003–2013), Landsat 7 (2003–2017), and Landsat 8 (2013–2017). Before conducting maximum likelihood remote sensing classification, the images acquired by the Landsat 7 were pre-processed to reduce the impact of the scan line corrector failure. The corrected images were subsequently used to classify 35 different land-use classes and 137 unique two-year-long sequences of 57 classes of non-urban and non-forested land-use categories from 2004 through 2014. Our final data product uses new and previously published results to classify the western Oregon landscape into 61 different land use classes, including four majority-rule-over-time super-classes and 57 regular classes of annually disturbed agricultural crops (19 classes), perennial crops (20 classes), forests (13 classes), and urban developments (5 classes). These publicly available data can be used to inform and support environmental and agricultural land-use studies.
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Colvin, Randall, Guillermo R. Giannico, Judith Li, Kathryn L. Boyer, and William J. Gerth. "Fish Use of Intermittent Watercourses Draining Agricultural Lands in the Upper Willamette River Valley, Oregon." Transactions of the American Fisheries Society 138, no. 6 (November 2009): 1302–13. http://dx.doi.org/10.1577/t08-150.1.

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Gilmour, Daniel M., Virginia L. Butler, Jim E. O'Connor, Edward Byrd Davis, Brendan J. Culleton, Douglas J. Kennett, and Gregory Hodgins. "Chronology and Ecology of Late Pleistocene Megafauna in the Northern Willamette Valley, Oregon." Quaternary Research 83, no. 1 (January 2015): 127–36. http://dx.doi.org/10.1016/j.yqres.2014.09.003.

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AbstractSince the mid-19th century, western Oregon's Willamette Valley has been a source of remains from a wide variety of extinct megafauna. Few of these have been previously described or dated, but new chronologic and isotopic analyses in conjunction with updated evaluations of stratigraphic context provide substantial new information on the species present, timing of losses, and paleoenvironmental conditions. Using subfossil material from the northern valley, we use AMS radiocarbon dating, stable isotope (δ13C and δ15N) analyses, and taxonomic dietary specialization and habitat preferences to reconstruct environments and to develop a local chronology of events that we then compare with continental and regional archaeological and paleoenvironmental data. Analysis of twelve bone specimens demonstrates the presence of bison, mammoth, horse, sloth, and mastodon from ~ 15,000–13,000 cal yr BP. The latest ages coincide with changing regional climate corresponding to the onset of the Younger Dryas. It is suggested that cooling conditions led to increased forest cover, and along with river aggradation, reduced the area of preferred habitat for the larger bodied herbivores, which contributed to the demise of local megafauna. Archaeological evidence for megafauna–human interactions in the Pacific Northwest is scarce, limiting our ability to address the human role in causing extinction.
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Stonewall, Adam J., Gregory E. Granato, and Tana L. Haluska. "Assessing Roadway Contributions to Stormwater Flows, Concentrations, and Loads with the StreamStats Application." Transportation Research Record: Journal of the Transportation Research Board 2672, no. 39 (April 11, 2018): 79–87. http://dx.doi.org/10.1177/0361198118758679.

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The Oregon Department of Transportation (ODOT) and other state departments of transportation need quantitative information about the percentages of different land cover categories above any given stream crossing in the state to assess and address roadway contributions to water-quality impairments and resulting total maximum daily loads. The U.S. Geological Survey, in cooperation with ODOT and the FHWA, added roadway and land cover information to the online StreamStats application to facilitate analysis of stormwater runoff contributions from different land covers. Analysis of 25 delineated basins with drainage areas of about 100 mi2 indicates the diversity of land covers in the Willamette Valley, Oregon. On average, agricultural, developed, and undeveloped land covers comprise 15%, 2.3%, and 82% of these basin areas. On average, these basins contained about 10 mi of state highways and 222 mi of non-state roads. The Stochastic Empirical Loading and Dilution Model was used with available water-quality data to simulate long-term yields of total phosphorus from highways, non-highway roadways, and agricultural, developed, and undeveloped areas. These yields were applied to land cover areas obtained from StreamStats for the Willamette River above Wilsonville, Oregon. This analysis indicated that highway yields were larger than yields from other land covers because highway runoff concentrations were higher than other land covers and the highway is fully impervious. However, the total highway area was a fraction of the other land covers. Accordingly, highway runoff mitigation measures can be effective for managing water quality locally, they may have limited effect on achieving basin-wide stormwater reduction goals.
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Wells, Ray E., Richard J. Blakely, and Sean Bemis. "Northward migration of the Oregon forearc on the Gales Creek fault." Geosphere 16, no. 2 (February 6, 2020): 660–84. http://dx.doi.org/10.1130/ges02177.1.

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Abstract The Gales Creek fault (GCF) is a 60-km-long, northwest-striking dextral fault system (west of Portland, Oregon) that accommodates northward motion and uplift of the Oregon Coast Range. New geologic mapping and geophysical models confirm inferred offsets from earlier geophysical surveys and document ∼12 km of right-lateral offset of a basement high in Eocene Siletz River Volcanics since ca. 35 Ma and ∼8.8 km of right-lateral separation of Miocene Columbia River Basalt at Newberg, Oregon, since 15 Ma (∼0.62 ± 0.12 mm/yr, average long-term rate). Relative uplift of Eocene Coast Range basalt basement west of the fault zone is at least 5 km based on depth to basement under the Tualatin Basin from a recent inversion of gravity data. West of the city of Forest Grove, the fault consists of two subparallel strands ∼7 km apart. The westernmost, Parsons Creek strand, forms a linear valley southward to Henry Hagg Lake, where it continues southward to Newberg as a series of en echelon strands forming both extensional and compressive step-overs. Compressive step-overs in the GCF occur at intersections with ESE-striking sinistral faults crossing the Coast Range, suggesting the GCF is the eastern boundary of an R′ Riedel shear domain that could accommodate up to half of the ∼45° of post–40 Ma clockwise rotation of the Coast Range documented by paleomagnetic studies. Gravity and magnetic anomalies suggest the western strands of the GCF extend southward beneath Newberg into the Northern Willamette Valley, where colinear magnetic anomalies have been correlated with the Mount Angel fault, the proposed source of the 1993 M 5.7 Scotts Mills earthquake. The potential-field data and water-well data also indicate the eastern, Gales Creek strand of the fault may link to the NNW-striking Canby fault through the E-W Beaverton fault to form a 30-km-wide compressive step-over along the south side of the Tualatin Basin. LiDAR data reveal right-lateral stream offsets of as much as 1.5 km, shutter ridges, and other youthful geomorphic features for 60 km along the geophysical and geologic trace of the GCF north of Newberg, Oregon. Paleoseismic trenches document Eocene bedrock thrust over 250 ka surficial deposits along a reverse splay of the fault system near Yamhill, Oregon, and Holocene motion has been recently documented on the GCF along Scoggins Creek and Parsons Creek. The GCF could produce earthquakes in excess of Mw 7, if the entire 60 km segment ruptured in one earthquake. The apparent subsurface links of the GCF to other faults in the Northern Willamette Valley suggest that other faults in the system may also be active.
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Whittier, Thomas R., Robert M. Hughes, and David P. Larsen. "Correspondence Between Ecoregions and Spatial Patterns in Stream Ecosystems in Oregon." Canadian Journal of Fisheries and Aquatic Sciences 45, no. 7 (July 1, 1988): 1264–78. http://dx.doi.org/10.1139/f88-149.

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Multivariate analyses of biotic assemblages and physicochemical measures, species richness, diversity, and composition were used to evaluate the robustness of Omernik's ecoregion classification for small streams in the eight ecoregions of Oregon. Clearest differences were between the montane and nonmontane regions. For the three nonmontane regions, ordinations of fishes, macroinvertebrates, water quality, and physical habitat measures show the clearest differences, with the Willamette Valley ecoregion being consistently most unlike all other regions. Differences between the Columbia Basin and High Desert regions were clearest for water quality and physical habitat measures and fish assemblages. Differences among the montane regions were subtle. Of these regions, the East Cascade Slopes showed the greatest variability, as shown by the ranges of ordination scores for fishes, water quality, and physical habitat. Regional patterns in periphyton assemblages were markedly different from the patterns in the other groups of variables. Ecoregions can be used as a broad-scale geographic framework for classifying streams. This framework provides managers of lotic resources a useful alternative to river basins.
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Peterson, Curt D., Kurt Kristensen, and Rick Minor. "Large-Scale Fluidization Features from Late Holocene Coseismic Paleoliquefaction in the Willamette River Forearc Valley, Central Cascadia Subduction Zone, Oregon, USA." Open Journal of Earthquake Research 03, no. 02 (2014): 82–99. http://dx.doi.org/10.4236/ojer.2014.32009.

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Loar, Todd N. "Qualitative Rock Wedge Stability Evaluation Performed For Foundation of Green Peter Dam, Oregon." Environmental and Engineering Geoscience 24, no. 1 (February 14, 2018): 55–73. http://dx.doi.org/10.2113/gseegeosci.24.1.55.

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Abstract Green Peter Dam is a concrete gravity structure located in west-central Oregon on the Middle Santiam River within the Willamette Valley Basin. A risk assessment for the project identified continuous and adversely oriented low-angled shear zones underlying portions of the foundation that could potentially facilitate sliding instability of one or more monoliths during earthquake loading. Conceptually, a potential foundation rock wedge could be formed with a shear zone as its sliding surface and joints as the side planes. This wedge, which would otherwise be stable under static conditions, could feasibly be displaced and/or shifted during seismic ground shaking, resulting in significant structural damage and/or breach of the dam. A qualitative evaluation was performed to characterize the geomechanical conditions and geometry of movement (i.e., kinematics) of the dam-foundation system associated with rock wedges. The study revealed that wedges could indeed be formed by adversely oriented and intersecting rock mass discontinuities. The qualitative evaluation concluded that the displacement geometry and geologic conditions in the foundation collectively suggest that the wedges would likely be stable under even large probabilistic seismic loading. While no concrete dams are known to have failed due to seismic loading, an increased knowledge of higher seismicity in the Pacific Northwest region warranted a careful evaluation to ensure that the risks of foundation rock wedge deformation are well characterized, and that our level of confidence in the available data is acceptable to better constrain the potential risk posed by this failure mode. This paper summarizes the background, findings, and results of the preliminary and qualitative dam-foundation system stability evaluation that was performed for Green Peter Dam.
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Dissertations / Theses on the topic "Geochemistry – Oregon – Willamette River Valley"

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Keeler, Elizabeth Louise. "Willamette Valley River Towns and Steamboats." Thesis, University of Oregon, 1985. http://hdl.handle.net/1794/22967.

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335 pages
This thesis describes the river towns along the Willamette River in Oregon. River conditions, adaptation of the boats to the river, and steamboat routes shown at ten year intervals illustrate the degree of accessibility of the various towns. Reasons for success or failure in light of factors of site, situation, efforts of townsite promoters or lack thereof are evaluated. Increase in population is used as a measure of success. Orientation to the river was reflected in town plans and location of land uses as sh own in early maps and views.
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Ferreira, Gabriela Ribeiro de Sena. "Arsenic Mobilization from Silicic Volcanic Rocks in the Southern Willamette Valley." PDXScholar, 2016. http://pdxscholar.library.pdx.edu/open_access_etds/2752.

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Volcanic tuffs and tuffaceous sediments are frequently associated with elevated As groundwater concentrations even though their bulk As contents (~ 5 mg kg-1; Savoie, 2013) are only marginally greater than the average crustal abundance of 4.8 mg g-1 (Rudnick & Gao, 2003). Thus, As mobilization must be facilitated by conditions particular to these rocks. Alkaline desorption, anionic competition, reactive glass dissolution, and reductive dissolution of iron oxides are proposed processes of As release from volcanic rocks. Geogenic As contamination of groundwater in the southern Willamette Valley in western Oregon has been well-documented since the early 1960s, and previous studies have identified the Little Butte Volcanics Series and Fisher and Eugene Formations as the source of As contamination. This study examines 19 samples from 10 units of ash flow tuffs and tuffaceous sediments within the Fisher Formation and Little Butte Volcanics Series, representing a range of weathering and devitrification, to determine conditions of mobilization and mineralogical constraints that control As release into solution. Leachate studies were conducted over a range of pH from 7 to 11, phosphate concentrations from 10 μM to 100 mM, and in time series from 4 to 196 hours. Results demonstrate that silicic volcanic tuffs are capable of mobilizing As in concentrations above regulatory limits at pH conditions produced naturally by the tuffs (pH 8-9) or with moderate concentrations of P (10-100 μM). Alteration products, e.g. zeolites and clays, appear to be the primary host phases for mobile As. Samples that do not contain these alteration products tend to produce concentrations of As well below regulatory limits and often below the instrument detection limits of this study. The type of alteration may influence As mobilization: tuffs containing more clays tend to mobilize As through surficial desorption, and tuffs containing more zeolites tend to mobilize As by dissolution or formation of colloids. Additionally, one volcaniclastic sample demonstrates that extremely elevated concentrations of As, up to 1000 μg/L are possible as a result of oxidative dissolution of As-bearing sulfide phases.
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Gilmour, Daniel McGowan. "Chronology and Ecology of Late Pleistocene Megafauna in the Northern Willamette Valley, Oregon." PDXScholar, 2011. https://pdxscholar.library.pdx.edu/open_access_etds/416.

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This study is an investigation of the timing of extinction of late Pleistocene, large bodied mammalian herbivores (megafauna) and of the environment in which they lived. The demise of the megafauna near the end of the Pleistocene remains unexplained. Owing to potential human involvement in the extinctions, archaeologists have been particularly concerned to understand the causes for faunal losses. Our current lack of understanding of the timing and the causes of the extinctions in North America may result from a deficiency in understanding the histories of each individual species of extinct animal on a local level. Detailed regional chronologies of fauna are necessary for comparison with paleoenvironmental and archaeological data to help sort out causes for extinction. The Willamette Valley of western Oregon has long been noted for finds of megafauna, though records have not been synthesized since the early 20th century and these materials have remained largely unstudied. In this thesis, I first create a catalog of extinct megafauna recovered from the Willamette Valley. Next, using material from the northern valley, I employ AMS radiocarbon dating, stable isotope δ¹³C and δ¹⁵N analyses, and gross inferences based on the dietary specializations and habitat preferences of taxa in order to reconstruct environments and to develop a local chronology of events that is then arrayed against archaeological and paleoenvironmental data. The results of this study indicate that megafaunal populations in the northern Willamette Valley were contemporaneous with the earliest known human populations of the Pacific Northwest, as well as later populations associated with the Clovis Paleoindian Horizon. Consistent with the overkill hypothesis, radiocarbon ages span the length of the Clovis window, but no ages are younger than Clovis. Moreover, all radiocarbon ages are older than or contemporaneous to the onset of the Younger Dryas Stadial. No age ranges fall exclusively within the Younger Dryas. Comparison of megafaunal ages and paleoenvironmental records support the view that climate change contributed to local animal population declines. Prior to ~13,000 cal BP, the Willamette Valley was an open environment; herbivores mainly consumed C₃ vegetation. The timing of the loss of megafauna coincides with increased forested conditions as indicated by regional paleoenvironmental reconstruction. As the timing of megafaunal decline correlates with Clovis, the onset of the Younger Dryas, and increased forested conditions, it is not possible with the data currently available to distinguish the cause of extinction in the Willamette Valley. The age ranges of the fauna coupled with taphonomic and geologic context indicate that the fauna are autochthonous to the Willamette Valley; they do not represent ice rafted carcasses or isolated skeletal elements transported from elsewhere during late Pleistocene glacial outburst floods.
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Chun, Nicholas. "Identifying Clusters of Non-Farm Activity within Exclusive Farm Use Zones in the Northern Willamette Valley." Thesis, Portland State University, 2017. http://pqdtopen.proquest.com/#viewpdf?dispub=10600978.

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This thesis provides an extensive look at where permitted non-farm uses and dwellings have clustered within Exclusive Farm Use (EFU) zones in the Northern Willamette Valley in Oregon. There is a looming concern that non-farm related uses and dwellings, or non-farm development, are conflicting with agricultural preservation strategies. Specifically, non-farm developments can potentially undermine the critical mass of farmland needed to keep the agricultural economy sustainable, but until now, studies have lacked spatially precise data to systematically track these phenomena. This thesis offers methodological contributions towards analyzing these operations and presents a broad account of what has been occurring in the region. Using permit approval data from the Department of Land Conservation and Development (DLCD) and 2015 county tax lot shapefiles, I geocoded the locations of these uses and dwellings. I used location quotient and spatial autocorrelation coefficients to identify non-farm hotspots in the region and summarized different typologies that have developed. The findings reveal that viticulture operations have amassed near Dundee and Newberg in Yamhill County, while commercial activities and home occupations have clustered near the Salem-Keizer UGB. Concurrently, dwellings have clustered near the Yamhill-Polk County border. Finally, I offer suggestions to improve Oregon’s agricultural land use policy and data management process, as well as advocate for more intensive research in the future to generate narratives for our results.

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Elder, J. Tait. "Exploring Prehistoric Salmon Subsistence in the Willamette Valley using Zooarchaeological Records and Optimal Foraging Theory." PDXScholar, 2010. https://pdxscholar.library.pdx.edu/open_access_etds/22.

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My research examines the prehistoric subsistence of native peoples of the Willamette Valley, Oregon through an analysis of the regional zooarchaeological records, and then modeling regional diet breadth. Through this analysis, I challenge commonly held stereotypes that the indigenous people of the Willamette Valley were strictly root eaters, and the basis for this claim, that salmon were not part of Native subsistence. The results of my research indicate that given the incomplete nature of the ethnohistoric record, very little can be said about expected cultural behaviors, such as salmon consumption, that appear to be absent in the Willamette Valley. In addition, since the faunal assemblage is so small in the Willamette Valley, zooarchaeological data are simply inadequate for studying the relationship between prehistoric peoples and their animal resources. Finally, optimal foraging modeling suggests that salmon is one of the higher ranked resources available to the Native People of the Willamette Valley.
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Cody, Tia Rachelle. "LiDAR Predictive Modeling of Kalapuya Mound Sites in the Calapooia Watershed, Oregon." PDXScholar, 2019. https://pdxscholar.library.pdx.edu/open_access_etds/4863.

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Archaeologists grapple with the problematic nature of archaeological discovery. Certain types of sites are difficult to see even in the best environmental conditions (e.g., low-density lithic scatters) and performing traditional archaeological survey is challenging in some environments, such as the dense temperate rain forests of the Pacific Northwest. Archaeologists need another method of survey to assess large areas and overcome environmental and archaeological barriers to site discovery in regions like the Pacific Northwest. LiDAR (light detection and ranging) technology, a method for digitally clearing away swaths of vegetation and surveying the landscape, is one possible solution to some of these archaeological problems. The Calapooia Watershed in the southern Willamette Valley in Oregon is an ideal area to focus LiDAR's unique archaeological capabilities, as the region is heavily wooded and known to contain hundreds of low-lying earthwork features or mounds. Modern Indigenous Communities, such as the Confederated Tribes of Grand Ronde, consider the Willamette Valley mound sites highly sensitive locations, as ethnographic accounts and limited archaeological work indicate that some are burial sites. However, these mounds have received little archaeological study. Land ownership (94 percent privately owned), dense vegetation that obscures mounds, and the sheer expanse of the landscape (234,000 acres) have impeded professional archaeological research. The focus of this thesis is the development and the testing of a LiDAR and remote sensing predictive model to see if this type of model can detect where potential mound sites are located in the Calapooia Watershed, Oregon. The author created a LiDAR and remote sensing predictive model using ArcMap 10.5.1, LiDAR, and publicly available aerial imagery; manipulating data using standard hydrological tools in ArcMap. The resulting model was successful in locating extant previously identified mound sites. The author then conducted field work and determined that the model was also successful in identifying seven new, previously unrecorded mound sites in the watershed. The author also identified several possible patterns in mound location and characteristics through exploratory model analysis and fieldwork; this exploratory analysis highlights areas for future mound research. This project has clearly established a method and a model appropriate for archaeological mound prospection in the Willamette Valley. This project also shows the efficacy of LiDAR predictive models and feature extraction methods for archaeological work, which can be modified for use in other regions of the Pacific Northwest and beyond. Furthermore, by identifying these mounds I have laid the groundwork for future studies that may continue to shed light on why and how people created these mounds, which will add valuable information to a poorly understood site type and cultural practice.
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Barnard, Kathryn Nora. "The Terroir of Pinot Noir Wine in the Willamette Valley, Oregon : A Broad Analysis of Vineyard Soils, Grape Juice and Wine Chemistry." PDXScholar, 2016. http://pdxscholar.library.pdx.edu/open_access_etds/2941.

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Terroir is determined by a combination of factors in the vineyard including the grape varietal, geology and soil, soil hydrology, physiography, and climate. Although most studies have examined regional differences in wine flavors and associated provenance of wine based on chemistry, few have examined the chemistry of the soil and the ability to trace that chemistry to grape juice and, finally, to the wine. This dissertation examines what soil physical and chemical differences specific to this region might influence grape juice chemistry and wine chemistry. Wine-grapes in the Willamette Valley, Oregon, are grown on three major soil parent materials: volcanic, marine sediments, and loess/volcanic. Winemakers have observed differences in the flavor of Pinot Noir wine made from grapes grown on these different parent materials. This dissertation examines differences in the soil properties and elemental chemistry of the soil parent materials at various vineyards to document their effect on wine chemistry as a step towards understanding differences in flavor. All aspects of the terroir are controlled by carefully selecting vineyards with similar exposure and elevation, the same grape varietal and wine making techniques, and only the soils vary. The hypothesis is that the chemistry of the grape juice and wine reflect the soil in which the grapes were grown and that the three parent materials have soils that can be distinguished by their physical and chemical characteristics. Soil pits were excavated in 20 vineyards, soil properties were described in the field, and soil samples were later analyzed in the laboratory particle size, organic matter, color, pH, cation exchange capacity (ammonium acetate method), clay mineralogy (x-ray diffraction), and elemental chemistry (ICP-MS/AES). X-ray fluorescence was used to examine the pisolites. ICP-MS/AES was used for elemental analysis of grape juice and wines produced from these vineyards. Principal component analysis was used to compare soil physical and chemical characteristics, grape juice and wine chemistry. The physical characteristics of soils from all the three parent materials indicate: they are old (>50,000 years) based on their high clay content, low cation exchange capacity, red colors, and high Fe and Al content. These features indicate enough time has passed to reduce organic matter and other cations at depth, leave behind insoluble Fe and Al, and develop pedogenic clays. In my study region, volcanic and marine sediment soils are more developed with slightly lower acidity than the loess/volcanic soils. A new finding for this region is the presence of pisolites (Fe/Mg concretions) in the volcanic and the loess/volcanic soils, but absent in the marine sediment soils. Winemakers hypothesized that pisolites were present only in loess soils and influenced wine flavor in some way. Volcanic soils have the highest P, S, Fe, Co, Mn, and V concentrations and the lowest As and Sr values. Marine sediment soils have higher Cl and Sr and lower P, Co, Mn, Ba, and V concentrations than volcanic soils. Loess soils have the highest values of K and Mg and are similar to volcanic soils with higher P and V values and similar to marine sediment soils with higher Sr values. The main elements found to be significant in determining one parent material from another are V and Mn (volcanic soils), Mg and K (loess soils), and Sr (marine sediment or loess soils). Sr is slightly higher in grape juice and wine from vines grown on marine sediment parent material compared to volcanic and loess parent material, whereas Mn is higher in the juice and wine from grapes grown in volcanic parent material. P, S, Fe, Co, V, Cl, Ba, Mg, and K did not maintain their relative concentration levels from soil to grape juice to wine. The principal component analysis shows that soil and wine chemistry differs between parent material, but is inconclusive for grape juice chemistry.
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Ulrich, Nathan D. 1977. "Restoring oak habitats in the Southern Willamette Valley, Oregon: A multi-objective tradeoffs analysis for landowners and managers." Thesis, University of Oregon, 2010. http://hdl.handle.net/1794/11087.

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xvii, 160 p. : ill. (some col.) A print copy of this thesis is available through the UO Libraries. Search the library catalog for the location and call number.
Restoring oak habitats is an emerging conservation priority in Oregon's Willamette Valley. Both private and public landowners face multiple challenges to conservation and restoration of oak habitats, including a lack of knowledge about the potential tradeoffs and constraints for achieving multiple priorities on a given site. This study simulated 25 alternative oak habitat restoration scenarios to develop estimates of outcomes related to six different restoration priorities: costs, income potential, habitat value, scenic quality, fire hazard reduction potential, and time requirements. Model results indicated that initial land conditions strongly influence a landowner's ability to optimize among these different priorities. To assist landowners with decision-making, model estimates were organized into a digital decision matrix that communicates advantages and tradeoffs associated with each alternative scenario. In doing so, it aims to help landowners choose restoration goals that better meet their broader needs and objectives.
Committee in Charge: Dr. Bart Johnson, Chair; Dr. Robert Ribe
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9

Sheehan, Timothy J. "Modeling Wildfire and Ignitions for Climate Change and Alternative Land Management Scenarios in the Willamette Valley, Oregon." Thesis, University of Oregon, 2011. http://hdl.handle.net/1794/12184.

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xii, 127 p. ： ill. (some col.)
I developed software to incorporate the FlamMap fire model into an agent-based model, Envision, to enable the exploration of relationships between wildfire, land use, climate change, and vegetation dynamics in the Willamette Valley. A dynamic-link library plug-in utilizing row-ordered compressed array lookup tables converts parameters between polygon-based Envision data and grid-based FlamMap data. Modeled fires are determined through Monte-Carlo draws against a set of possible fires by linking historic fire data to future climate projections. I used classification and regression tree (CART) and logistic regression to relate ignitions to human and land use factors in the Willamette Valley above the valley floor from 2000-2009. Both methods showed decreasing distance to major and minor roads as key factors that increase ignition probability for human ignitions but not for lightning ignitions. The resulting statistical model is implemented in the FlamMap plug-in to provide a dynamic ignition probability map over time.
Committee in charge: Dr. Bart Johnson， Co-Chair； Dr. Scott Bridgham ，Co-Chair； Dr. John Bolte； Member
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Smith, Cessna R. "The Pursuit of Commerce: Agricultural Development in Western Oregon, 1825-1861." PDXScholar, 2011. https://pdxscholar.library.pdx.edu/open_access_etds/258.

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This thesis examines how the pursuit of commercial gain affected the development of agriculture in western Oregon's Willamette, Umpqua, and Rogue River Valleys. The period of study begins when the British owned Hudson's Bay Company began to farm land in and around Fort Vancouver in 1825, and ends in 1861--during the time when agrarian settlement was beginning to expand east of the Cascade Mountains. Given that agriculture in Oregon, as elsewhere, would eventually reach a standard of national development, and given that most of Oregon's immigrants arrived poor and lacked the farm implements needed for subsistence, the question this study asks is what methods and motivations guided Oregon's first agrarian settlers to improve their industry? It is the central premise of this study that commerce was the sine qua non of agricultural development, and that commercial gain was the incentive that underpinned the improvements necessary to its progress. The question itself necessarily involves physiographical and climatological conditions, existing and potential markets, and a merchant class whose commercial motivations were beyond doubt. Two additional matters that weigh substantially through most of this paper need to be mentioned: First, because not all farmers were commercially-oriented, the focus is on individuals, including merchants, whose entrepreneurial activities contributed the most to agriculture; second, the discovery of gold in California in 1848, and in southern Oregon in the early 1850s, had a huge and lasting influence on Oregon agriculture and on the overall economy.
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Books on the topic "Geochemistry – Oregon – Willamette River Valley"

1

Williams, Travis. The Willamette River field guide. Portland: Timber Press, 2009.

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Seter, Lisa M. Geochemical characteristics of iron-manganese nodules in seasonally-saturated soils of the Willamette Valley, Oregon. 1998.

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Lonely Planet Pocket Portland and the Willamette Valley. Lonely Planet Publications, 2020.

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Metzger, Abby Phillips. Meander Scars: Reflections on Healing the Willamette River. Oregon State University Press, 2013.

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Metzger, Abby Phillips, and Lorraine Anderson. Wild in the Willamette: Exploring the Mid-Valley's Parks, Trails, and Natural Areas. Oregon State University Press, 2015.

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Stepp, David. Descriptive analysis of human remains from the Fuller and Fanning Mounds, Yamhill River, Willamette Valley, Oregon. 1994.

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George, Mason Robert, Cross Timothy L, Nuckton Carole Frank, and Oregon State University. Agricultural Experiment Station., eds. IRCA and Oregon agricultural industries: Nursery crops, Christmas trees, and strawberries in the Willamette Valley, and pears in the Hood River Valley. [Corvallis, Or.]: Agricultural Experiment Station, Oregon State University, 1993.

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Dangerous Subjects: James D. Saules and the Rise of Black Exclusion in Oregon. Oregon State University Press, 2017.

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Book chapters on the topic "Geochemistry – Oregon – Willamette River Valley"

1

Gannett, Marshall W., and Dennis G. Woodward. "Groundwater and Surface-Water Relations in the Willamette Valley, Oregon." In River Quality, 131–39. CRC Press, 2018. http://dx.doi.org/10.1201/9780203740576-9.

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"Status, Distribution, and Conservation of Native Freshwater Fishes of Western North America." In Status, Distribution, and Conservation of Native Freshwater Fishes of Western North America, edited by Paul D. Scheerer. American Fisheries Society, 2007. http://dx.doi.org/10.47886/9781888569896.ch9.

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ABSTRACT Status and trends in the abundance of populations of federally endangered Oregon chub <em>Oregonichthys</em> <em>crameri</em>, small floodplain minnows endemic to the Willamette Valley of western Oregon, were investigated by estimating fish abundance and from extensive fish surveys of 650 off-channel habitats from 1991 through 2004. The recent discovery of previously unknown populations of Oregon chub, some occurring in subbasins where they were presumed extinct, combined with successful reintroductions into suitable habitats have resulted in the improved status of this species. In 1991, eight populations of Oregon chub were known to exist. In 2004, we identified 33 populations of Oregon chub in the Willamette River basin. Ten of these populations, including the two most abundant populations, were introduced. The status of Oregon chub is approaching the recovery plan goal for downlisting the species to threatened. Nonnative fishes, which were found to be widespread in off-channel habitats preferred by Oregon chub, are the largest threat to full recovery and delisting of this species.
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Burt, Walter, Terrence Conlon, Terry L. Tolan, Ray E. Wells, and Jason Melady. "Hydrogeology of the Columbia River Basalt Group in the northern Willamette Valley, Oregon." In Volcanoes to Vineyards: Geologic Field Trips through the Dynamic Landscape of the Pacific Northwest, 697–736. Geological Society of America, 2009. http://dx.doi.org/10.1130/2009.fld015(31).

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White, Robert E. "Putting it All Together." In Understanding Vineyard Soils. Oxford University Press, 2015. http://dx.doi.org/10.1093/oso/9780199342068.003.0009.

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In reality, there can be no generic definition of an “ideal soil” because a soil’s performance is influenced by the local climate, landscape characteristics, grape variety, and cultural practices and is judged in the context of a winegrower’s objectives for style of wine to be made, market potential, and profitability of the enterprise. This realization essentially acknowledges the long-established French concept of terroir: that the distinctiveness or typicity of wines produced in individual locations depends on a complex interaction of biophysical and human cultural factors, interpreted by many as meaning a wine’s sense of place. As discussed in “Soil Variability and the Concept of Terroir” in chapter 1, because of this interaction of factors that determine a particular terroir, it is not surprising that no specific relationships between one or more soil properties and wine typicity have been unequivocally demonstrated. While acknowledging this conclusion, it is still worthwhile to examine how variations in several single or combined soil properties can influence vine performance and fruit character. These properties are: • Soil depth • Soil structure and water supply • Soil strength • Soil chemistry and nutrient supply • Soil organisms Provided there are no subsoil constraints, the natural tendency of long-lived Vitis vinifera, on own roots or rootstocks, to root deeply and extensively gives it access to a potentially large store of water and nutrients. In sandy and gravely soils that are naturally low in nutrients, such as in the Médoc region of France, the Margaret River region in Western Australia, and the Wairau River plain, Marlborough region, New Zealand, the deeper the soil the better. A similar situation pertains on the deep sandy soils on granite in the Cauquenas region, Chile. However, such depth may be a disadvantage where soils are naturally fertile and rain is plentiful, as in parts of the Mornington Peninsula, King and Yarra Valley regions, Victoria, Australia, and the Willamette Valley region in Oregon (see figure 1.11, chapter 1), because vine growth is too vigorous and not in balance.
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Reports on the topic "Geochemistry – Oregon – Willamette River Valley"

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Lighthart, Bruce, B. T. Shaffer, A. S. Frisch, and D. Paterno. Meteorological Variables Associated with Population Density of Culturable Atmospheric Bacteria at a Summer Site in the Mid-Willamette River Valley, Oregon. Fort Belvoir, VA: Defense Technical Information Center, September 2004. http://dx.doi.org/10.21236/ada427789.

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