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- Arsenic -- Environmental aspects -- Western Oregon (2)
- Geotechnical engineering (2)
- Soil pollution -- Western Oregon (2)
- Soils -- Arsenic content -- Western Oregon (2)
- Bacteria biofilm (1)
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- Calcium montmorillonite (1)
- Calcretes -- Pacific Northwest (1)
- Carbon sequestration (1)
- Clouds (1)
- Convection (1)
- Debris avalanches (1)
- Debris avalanches -- Southeast Alaska (1)
- Debris avalanches -- Washington (State) -- Mount Saint Helens (1)
- Diatomaceous earth (1)
- Diatoms (1)
- Drainage -- Oregon -- Portland (1)
- FTIR (1)
- Floods -- Pacific Northwest (1)
- Geology -- Columbia River Gorge (Or. and Wash.) (1)
- Geology -- Oregon -- Rainier (1)
- Glacial lakes -- Montana (1)
- Grape juice (1)
- Hazard mitigation -- Pacific Northwe (1)
- Kaolinite (1)
- Lake Missoula (1)
- Landslides -- Southeast Alaska (1)
- Landslides -- Washington (State) -- Mount Saint Helens (1)
- Mycorrhizal fungi (1)
- Paleopedology -- Pacific Northwest -- Quaternary (1)
- Pinot noir (Wine) -- Oregon -- Willamette River Valley (1)
Articles 1 - 19 of 19
Full-Text Articles in Physical Sciences and Mathematics
Post-Fire Erosional And Hydrological Processes Promoting Debris Flow Initiation In A Douglas Fir And Western Hemlock Forest In The Riverside Burn Area, Oregon, Morena Nicole Hammer
Post-Fire Erosional And Hydrological Processes Promoting Debris Flow Initiation In A Douglas Fir And Western Hemlock Forest In The Riverside Burn Area, Oregon, Morena Nicole Hammer
Dissertations and Theses
Post-fire debris flows initiated by overland flow in the Pacific Northwest (PNW) are largely undocumented. Instead, debris flows are typically initiated by shallow landslides that result in a mud slurry of water and sediments traveling downhill under the force of gravity. However, because of the Fall 2020 fires in Oregon, the typical initiation style and erosional patterns in burned catchments may have changed because of unusually high burn severity. Due to the intensity of these fires, we set out to determine how hydrologic processes and erosion occurred, when they occurred, and what process was primarily responsible for the erosion that …
Using Quantitative Stereology On High Resolution Sem Images To Estimate Diatom Percentages, Ariadna Covarrubias Ornelas
Using Quantitative Stereology On High Resolution Sem Images To Estimate Diatom Percentages, Ariadna Covarrubias Ornelas
Dissertations and Theses
Diatoms are single-celled organisms of various shapes and sizes typically found in aquatic environments. When diatoms die, the organic material decomposes, and the outer skeletons (i.e., frustules) settle and accumulate as sedimentary deposits. These soils, called diatomaceous soils, exhibit nontraditional behavior since the diatom particles are typically hollow skeletons composed of amorphous silica with intricately patterned and abrasive surfaces. Recent studies have shown that diatomaceous soils are challenging geomaterials since even a small percentage of diatom particles will notably affect engineering behavior. Furthermore, laboratory studies on diatomaceous soil mixtures have demonstrated that many engineering soil properties depend on the percentage …
Field Trials And Long-Term Monitoring Of Microbially-Induced Desaturation For The Treatment Of Liquefiable Silty Soils, Kayla Rae Sorenson
Field Trials And Long-Term Monitoring Of Microbially-Induced Desaturation For The Treatment Of Liquefiable Silty Soils, Kayla Rae Sorenson
Dissertations and Theses
Earthquake liquefaction hazards in silty soils are a critical problem in Portland, Oregon, and other areas around the world. This is a particular problem for existing facilities founded on liquefiable soils, for which there exists no cost-effective liquefaction mitigation solution at the present time. It is essential from both a seismic safety and a seismic resilience perspective to be able to mitigate potentially liquefiable soils underneath existing structures, and to do so in a cost-effective manner. Recent studies suggest that liquefaction mitigation using microbially-induced desaturation (MID) may provide this capability.
The objective of MID is to reduce earthquake-induced excess pore …
Amount And Depositional Fate Of Carbon Mobilized By Landsliding In Se Alaska, Bryce Alois Vascik
Amount And Depositional Fate Of Carbon Mobilized By Landsliding In Se Alaska, Bryce Alois Vascik
Dissertations and Theses
Forest disturbances in the form of landslides mobilize carbon (C) sequestered in vegetation and soils. The mobilized C has two basic depositional fates, deposition onto hillslopes or into water, which sequester C from and release C to the atmosphere at different time scales. The C-dense old-growth temperate forests of SE Alaska are a unique location to quantify the C mobilization rate by frequent landslide events. In this study, we estimate the amount of C mobilized by debris flows over historic time scales by combining a landslide inventory with maps of modeled biomass and soil carbon. We then infer depositional fate …
Mit-S1 Constitutive Model Calibration For A Portland-Area Soil, Steven Ryan Young
Mit-S1 Constitutive Model Calibration For A Portland-Area Soil, Steven Ryan Young
Dissertations and Theses
Soils that are intermediate to sands and clays are a challenge for geotechnical engineers since most methods for interpreting soil properties or soil behaviors are based on sands or clays and do not address behaviors of intermediate soils. This is a particular challenge for engineers in the Portland-area where many of the major soil units are composed of intermediate soils. Analysis of intermediate soils is further challenged since many standard constitutive models are based on sandy or clay-like soils. However, the MIT-S1 constitutive model is capable of capturing intermediate soil behavior. A calibration of the MIT-S1 constitutive model for Portland-area …
Relationships Between In-Situ Tests And Soil Cyclic Strength For Earthquake Hazard Characterization In The Pacific Northwest, Tanner Scott Bryantt
Relationships Between In-Situ Tests And Soil Cyclic Strength For Earthquake Hazard Characterization In The Pacific Northwest, Tanner Scott Bryantt
Dissertations and Theses
Strong earthquake shaking is a natural hazard threat in the Pacific Northwest. Soil failure due to strong earthquake shaking -- known as cyclic soil failure or liquefaction -- is expected to cause large ground deformations and damage to roads, bridges, and other civil infrastructure. Cyclic soil strength (CRR) is often characterized with in-situ geotechnical tests including the cone penetration test (CPT). Relationships between CRR and in-situ test data are not well established for soils in the Pacific Northwest. Portland State University, in partnership with New Albion Geotechnical has compiled a database of cyclic lab tests for Pacific Northwest soils to …
Do Fungal Symbionts Of Salt Marsh Plants Affect Interspecies Competition?, Vanessa Robertson-Rojas
Do Fungal Symbionts Of Salt Marsh Plants Affect Interspecies Competition?, Vanessa Robertson-Rojas
Dissertations and Theses
The effects of arbuscular mycorrhizal fungi (AMF) as salt marsh plant symbionts may have significant effects on landscape scale distribution patterns and plant-related ecosystem functions that are important to estuarine habitats. This work investigates the effects AMF have on Phalaris arundinacea, Deschampsia cespitosa, and Juncus balticus when grown in a common garden experiment. Plants were grown with and without AMF inoculation in both polyculture and monoculture communities and examined for a variety of response variables that represent different competition strategies. Factorial ANOVA analysis revealed a significant three-way interaction among fungal treatment type, community type, and species for …
Ftir Analysis Of Bacteria Biomass-Mineral Interactions In Soils, Finola Fung-Khee
Ftir Analysis Of Bacteria Biomass-Mineral Interactions In Soils, Finola Fung-Khee
Dissertations and Theses
Soil organic carbon (SOC) accounts for 70% of the carbon on Earth. It is therefore a key player in global carbon cycling and climate change (Smith et al., 2008). Soil organic matter (SOM) is an important component of organic matter in soils (SOC), and results from biogeochemical process involving net primary producers, soil biomass and soil mineralogy (Horwath and Kuzyakov, 2018). In this study, the interplay between soil bacterial biomass and reactive clay minerals in soils was investigated. The purpose of the research was to shed light into the stabilization of SOC in a bacterial biomass-soil/clay matrix. Soils characterized as …
Soil Phosphorus Characterization And Vulnerability To Release In Urban Stormwater Bioretention Facilities, Benjamin James Shetterly
Soil Phosphorus Characterization And Vulnerability To Release In Urban Stormwater Bioretention Facilities, Benjamin James Shetterly
Dissertations and Theses
Modern urban stormwater infrastructure includes vegetated bioretention facilities (BRFs) that are designed to detain water and pollutants. Phosphorus (P) is a pollutant in stormwater which can be retained in BRF soils in mineral, plant, and microbial pools. We explored soil properties and phosphorus forms in the soils of 16 operational BRFs in Portland, OR. Since soil hydrology can significantly impact P retention, we selected BRFs along an infiltration rate (IR) gradient. We conducted sequential fractionation and tests of P pools and measured P release in a subset of soils after drying and flooding samples for ten days. We hypothesized that …
The Terroir Of Pinot Noir Wine In The Willamette Valley, Oregon : A Broad Analysis Of Vineyard Soils, Grape Juice And Wine Chemistry, Kathryn Nora Barnard
The Terroir Of Pinot Noir Wine In The Willamette Valley, Oregon : A Broad Analysis Of Vineyard Soils, Grape Juice And Wine Chemistry, Kathryn Nora Barnard
Dissertations and Theses
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, …
Naturally Occurring Background Levels Of Arsenic In The Soils Of Southwestern Oregon, Heather Ann Hurtado
Naturally Occurring Background Levels Of Arsenic In The Soils Of Southwestern Oregon, Heather Ann Hurtado
Dissertations and Theses
This study examines the natural background concentrations of arsenic in the soils of southwest Oregon, using new samples in addition to data collected from previous theses (Khandoker, 1997 and Douglas, 1999). The original 213 samples were run by ICP-AES with a reporting limit of 20 ppm, and only three samples had detected values. The original samples were tested again (2013) at a lower reporting limit of 0.2 ppm by ICP-MS, as were 42 new samples (2013), to better ascertain the natural levels of arsenic in undisturbed soils. The aim is to add to the existing DEQ data set, which has …
Defining The Terroir Of The Columbia Gorge Wine Region, Oregon And Washington, Usa Using Geographic Information Systems (Gis), Hilary Whitney
Defining The Terroir Of The Columbia Gorge Wine Region, Oregon And Washington, Usa Using Geographic Information Systems (Gis), Hilary Whitney
Dissertations and Theses
The Columbia Gorge Wine Region (CGWR) is an emerging wine producing area that extends for about 100km along the Columbia River in Oregon and Washington State in which the number of vineyards, wineries and physical terroir conditions have yet to be defined. To better understand the physical factors affecting Oregon and Washington wine, this project analyzes climate, topography, geology and soil at vineyards in the CGWR. This was accomplished using Geographic Information Systems, existing earth science databases and field work. The region, which includes the Columbia Gorge American Viticulture Area (AVA) and the southwest portion of the Columbia Valley AVA, …
Characterization Of Tropical Clouds Using Multi-Satellite Observations, Ricardo Anderson
Characterization Of Tropical Clouds Using Multi-Satellite Observations, Ricardo Anderson
Dissertations and Theses
Clouds an important component of the earth-climate system and play a critical role in affecting energy and water cycle of the planet. In particular, tropical convective clouds account for the majority of the precipitation that fall on the Earth's surface. Multiple active satellite missions in recent decade such as TRMM (Tropical Rainfall Measurement Mission), and CloudSat have provided fruitful new insight into the internal structures of these tropical convective clouds. In conjunction with cloud data from ISCCP (International Satellite Cloud Climatology Project), that is based passive remote sensing technology in the visible and infrared spectrum, this allows for a more …
Map-Based Probabilistic Infinite Slope Analysis Of The Stephens Creek Watershed, Portland, Oregon, Ryan Andrew Cole
Map-Based Probabilistic Infinite Slope Analysis Of The Stephens Creek Watershed, Portland, Oregon, Ryan Andrew Cole
Dissertations and Theses
The Stephens Creek Watershed in southwest Portland, Oregon was chosen by the city as a pilot project for urban stream restoration efforts, and the infiltration of stormwater was identified as a potential restoration strategy. The Stephens Creek Watershed has historically been known to be unstable during high precipitation events (Burns, 1996), and the need to address the response of slope stability to anthropogenically-driven changing groundwater conditions is the focus of this study. Airborne light detection and ranging (LiDAR) and geotechnical data from the City of Portland were employed to create a high resolution (0.84 m2) physics-based probabilistic slope stability model …
Arsenic In The Soils Of Northwest Oregon, Tracy Ryan Ricker
Arsenic In The Soils Of Northwest Oregon, Tracy Ryan Ricker
Dissertations and Theses
One hundred and eighty-six soil samples from Northwest Oregon were tested for arsenic content. The highest values measured were 13.9 ppm in the A horizon (site C4) and 20.4 ppm in the B horizon (Site P4). Arsenic was not detected in 28 A horizon samples and 23 B horizon samples. Data are grouped based on the age and rock type of underlying bedrock. Lithologic groups with six or more data points were compared statistically to ascertain if groups are distinct. Analysis of Variance (ANOVA) multiple comparison tests indicate that the arsenic content of the Marine Sediments and Sedimentary Rocks group …
Inventory And Initiation Zone Characterization Of Debris Flows On Mount St. Helens, Washington Initiated During A Major Storm Event In November, 2006, Keith Vinton Olson
Inventory And Initiation Zone Characterization Of Debris Flows On Mount St. Helens, Washington Initiated During A Major Storm Event In November, 2006, Keith Vinton Olson
Dissertations and Theses
The heavy precipitation event of November 3-8, 2006 dropped over 60 cm of rain onto the bare southern slopes of Mount St. Helens and generated debris flows in eight of the sixteen drainages outside the 1980 debris avalanche zone. Debris flows occurred on the upper catchments of the Muddy River, Shoestring Glacier, Pine Creek, June Lake, Butte Camp Dome, Blue Lake, Sheep Creek, and South Fork Toutle River. Debris flows were clustered on the west and south-east sides of the mountain. Of the eight debris flows, three were initiated by landslides, while five were initiated by headward or channel erosion. …
Ancient Cataclysmic Floods In The Pacific Northwest: Ancestors To The Missoula Floods, Erica Medley
Ancient Cataclysmic Floods In The Pacific Northwest: Ancestors To The Missoula Floods, Erica Medley
Dissertations and Theses
Ancient Cataclysmic Floods were the Ice Age Floods that left erosional and depositional features and preceded the Missoula Floods (15-18,000 ka) in the Pacific Northwest of the United States (Allen et al., 2009). All previously studied ancient sites were visited (14) and new sites (11) were found; four Missoula Flood quarries were also visited; a total of 29 sites were studied in this thesis. The use of calcrete paleosols to provide relative age dates for flood deposits was analyzed in this thesis. Missoula Flood gravel pits were sampled in order to examine the degree of calcrete development in flood deposits …
Distribution Of Heavy Metals And Trace Elements In Soils Of Southwest Oregon, Rafiqul Alam Khandoker
Distribution Of Heavy Metals And Trace Elements In Soils Of Southwest Oregon, Rafiqul Alam Khandoker
Dissertations and Theses
Soil samples from 118 sites on 71 geologic units in southwest Oregon were collected and analyzed to determine the background concentrations of metals in soils of the region. Sites were chosen in areas that were relatively undisturbed by human activities. The U.S. Environmental Protection Agency approved total-recoverable method was used to recover metals from samples for analysis. The twenty six metals analyzed were: Ag, AI, As, Ba, Be, Ca, Cd, Co, Cr, Cu, Fe, Hg, K, La, Li, Mg, Mn, Mo, Na, Ni, Pb, Sb, Se, Tl, V and Zn.
The Klamath Mountains followed by the Coast Range contain the …
Slope Stability As Related To Geology At Rainier, Columbia County, Oregon, James Douglas Gless
Slope Stability As Related To Geology At Rainier, Columbia County, Oregon, James Douglas Gless
Dissertations and Theses
Rainier, Oregon, has experienced problems in the development of residential and commercial sites, utilities, and transportation facilities as a result of slope instability. This study of slope stability at Rainier was conducted at the request of city officials.