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Articles 1 - 20 of 20
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A Mixed Methods Approach To Understanding The Links Between Mining, Climate Change And Selected Health Outcomes In India, Mary J. Cheruvillil
A Mixed Methods Approach To Understanding The Links Between Mining, Climate Change And Selected Health Outcomes In India, Mary J. Cheruvillil
Dissertations and Theses
Despite ample evidence of the significant role that mining activities play in determining health outcomes, in India there is a dearth of comprehensive health studies that draw linkages between mining and health. The purpose of the following study is to investigate the impact of mining activities on population health in India using three different methods: ecological multivariable regression, exploratory spatial data analysis (ESDA) and content analysis of government documents using a phenomenological approach. The first aim uses the ecological multivariable regression to examine associations between mining activities and children’s malnutrition outcomes at the district level. Census data, the Demographic Health …
Data Fusion And Synergy Of Active And Passive Remote Sensing; An Application For Freeze Thaw Detections, Zahra Sharifnezhadazizi
Data Fusion And Synergy Of Active And Passive Remote Sensing; An Application For Freeze Thaw Detections, Zahra Sharifnezhadazizi
Dissertations and Theses
There has been a recent evolvement in the field of remote sensing after increase of number satellites and sensors data which could be fused to produce new data and products. These efforts are mainly focused on using of simultaneous observations from different platforms with different spatial and temporal resolutions. The research dissertation aims to enhance the synergy use of active and passive microwave observations and examine the results in detection land freeze and thaw (FT) predictions. Freeze thaw cycles particularly in high-latitude regions have a crucial role in many applications such as agriculture, biogeochemical transitions, hydrology and ecosystem studies. The …
Detecting Geomorphic Change And Stream Channel Evolution On The Sandy River, Oregon, Using Lidar Following Dam Removal In 2007, Lowell Henry Anthony
Detecting Geomorphic Change And Stream Channel Evolution On The Sandy River, Oregon, Using Lidar Following Dam Removal In 2007, Lowell Henry Anthony
Dissertations and Theses
Following the removal of Marmot Dam on the Sandy River, Oregon, several Lidar flights were flown over the area of the former reservoir. The resultant sequential DEMs permitted calculation of reach-scale volumetric erosion and aggradation following dam removal. This allows for change detection across the entire affected reach of the former impoundment rather than just at several cross sections. In the first year there was a net loss of blank sediment in the dewatered reach. Subsequent flights show continued degradation of 145,649 m3 as well as aggradation of 6,232 m3. Sediment transport reached quasi-equilibrium in 2012 with …
Seismic Source Characterization Of Faults In The Portland And Tualatin Basins And A Paleoseismic Study Of The Gales Creek Fault, Or, Alison Elizabeth Horst
Seismic Source Characterization Of Faults In The Portland And Tualatin Basins And A Paleoseismic Study Of The Gales Creek Fault, Or, Alison Elizabeth Horst
Dissertations and Theses
Portland, OR lies within the tectonically active forearc of the Cascadia subduction zone. Several, potentially hazardous, northwest striking faults in and around the Portland Basin are classified as Quaternary active by the USGS, but little is known about their Holocene activity. Geologic and geodetic studies in the Pacific Northwest (PNW) document ongoing clockwise rotation of the region since at least 16 Ma. Models for crustal deformation in the PNW suggest northwest trending faults accommodate dextral shear inferred from increasing clockwise rotation rates west of Portland. I compiled structural information to improve the seismic source characterization of these faults, and using …
Chronology And Ecology Of Late Pleistocene Megafauna In The Northern Willamette Valley, Oregon, Daniel Mcgowan Gilmour
Chronology And Ecology Of Late Pleistocene Megafauna In The Northern Willamette Valley, Oregon, Daniel Mcgowan Gilmour
Dissertations and Theses
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 …
Designing And Using Virtual Field Environments To Enhance And Extend Field Experience In Professional Development Programs In Geology For K-12 Teachers, Frank Douglas Granshaw
Designing And Using Virtual Field Environments To Enhance And Extend Field Experience In Professional Development Programs In Geology For K-12 Teachers, Frank Douglas Granshaw
Dissertations and Theses
Virtual reality (VR) is increasingly used to acquaint geoscience novices with some of the observation, data gathering, and problem solving done in actual field situations by geoscientists. VR environments in a variety of forms are used to prepare students for doing geologic fieldwork, as well as to provide proxies for such experience when venturing into the field is not possible. However, despite increased use of VR for these purposes, there is little research on how students learn using these environments, how using them impacts student field experience, or what constitutes effective design in light of emerging theories of geocognition.
To …
Deforestation, Drought And Humans: New Discoveries Of The Late Quaternary Paleoenvironment Of Rapa Nui (Easter Island), Candace Lynn Gossen
Deforestation, Drought And Humans: New Discoveries Of The Late Quaternary Paleoenvironment Of Rapa Nui (Easter Island), Candace Lynn Gossen
Dissertations and Theses
The mystery of the trees of Rapa Nui (Easter Island) is a complex problem within a dynamic ecosystem. With new physical cores from the volcanic crater lake Rano Kao, this dissertation uncovers a detailed 15,000 year ecological history of Easter Island and its climatic variability. New radiocarbon dating methods establish a more precise chronology which shows that the island before human habitation was very different than what we know today. It had a simple but prolific ecology that transitioned into a barren grassland. What factors caused the transition are unclear but are likely to be human related. As the forests …
Radiative Transfer Theory Applied To Ocean Bottom Modeling, Jorge Quijano
Radiative Transfer Theory Applied To Ocean Bottom Modeling, Jorge Quijano
Dissertations and Theses
Research on the propagation of acoustic waves in ocean bottom sediment is of interest for active sonar applications such as target detection and remote sensing. Currently, all seabed scattering models available in the literature are based on the full solution of the wave equation, which sometimes leads to mathematically intractable problems. In the electromagnetics community, an alternative formulation that overcomes some of this complexity is radiative transfer theory, which has established itself as an important technique for remote sensing. In this work, radiative transfer (RT) theory is proposed for the first time as a tool for the study of seabed …
Initiation Zone Characterization Of Debris Flows In November, 2006, Mount Hood, Oregon, Rachel Pirot
Initiation Zone Characterization Of Debris Flows In November, 2006, Mount Hood, Oregon, Rachel Pirot
Dissertations and Theses
In November, 2006, a storm generated a minimum of 34 cm of precipitation in six days, triggering debris flows in many of the drainages on all sides of Mount Hood, Oregon. Of the eleven drainages surveyed, seven experienced debris flows; these include the White River, Salmon River, Clark Creek, Newton Creek, Eliot Creek, Ladd Creek and Sandy River basins. Flows in the White River, Eliot Creek, and Newton Creek, caused major damage to bridges and roadways. Initiation elevations averaged around 1,860 meters. Initiation zone material was predominantly sand (45-82%) with gravel (15-49%) and had few fines (3-5%). Four debris flows …
Magmatic Processes Operating During The Middle To Late Pliocene And Pleistocene Along The Transition Zone Near 43º North, Christy L. Lee
Magmatic Processes Operating During The Middle To Late Pliocene And Pleistocene Along The Transition Zone Near 43º North, Christy L. Lee
Dissertations and Theses
A geochemical and structural transition zone exists between the Cascades and Basin and Range provinces in Oregon. Geologic mapping in this area has allowed the definition of six volcanic rock sequences: 1) interfingered alkali-rich basaltic trachyandesite to trachydacite lava flows and low-alkali basaltic andesite lava flows, 2) HAOT lava flows, 3) basaltic andesite lava flows, 4) andesite lava flows and vent deposits with minor basaltic andesite lava flows, 5) HAB lava flows, and 6) interfingered basaltic andesite, andesite, and trachyandesite lava flows.
Geochemical models of sequence 1 alkali-rich rocks suggest the fractionation of the parent assemblage plag (An55)+magn+ol±aug …
Post-Middle Miocene Geologic History Of The Tualatin Basin, Oregon With Hydrogeologic Implications, Doyle Coley Wilson
Post-Middle Miocene Geologic History Of The Tualatin Basin, Oregon With Hydrogeologic Implications, Doyle Coley Wilson
Dissertations and Theses
The geologic history and sedimentary till of the Tualatin Basin after Columbia River Basalt Group (CRBG) emplacement is assessed and related to groundwater characteristics. The 334 m deep HBD-1 core from the Hillsboro Airport, provides the primary information for sediment characterization and is supported by over 2400 well logs and cores, and four seismic lines. The sedimentary section above the 26 m thick paleosol on the CRBG in HBD-I is divided into two main groups: a 25 m thick section of Missoula flood sediments called the Willamette Silt overlies a 263 m thick finegrained sequence of fluvial Neogene sediments.
Pollen, …
The Geology Of Parrett Mountain, Oregon, And Its Influences On The Local Groundwater Systems, Brett Todd Brodersen
The Geology Of Parrett Mountain, Oregon, And Its Influences On The Local Groundwater Systems, Brett Todd Brodersen
Dissertations and Theses
A geologic study of the Parrett Mountain area, located twenty miles (32 kms) south-southwest of Portland, Oregon, was initiated by the Oregon Water Resources Department. The main goal was to create a stratigraphic and structural model of Parrett Mountain in order to better understand the local basalt aquifers present there.
Previous geologic studies of the area revealed the mountain to be composed of Columbia River basalt. Field mapping and hand lithologic and geochemical analyses allowed the basalt to be subdivided into eleven basalt flows. These flows are as follows: (from oldest to youngest) the Wapshilla Ridge (WpR), the Ortley-Grouse Creek …
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.
Development And Application Of Some Quantitative Stratigraphic Techniques To The Coos Bay Coalfield, A Tertiary Fluvio-Deltaic Complex In Southwestern Oregon, Willard Sidney Titus Iii
Development And Application Of Some Quantitative Stratigraphic Techniques To The Coos Bay Coalfield, A Tertiary Fluvio-Deltaic Complex In Southwestern Oregon, Willard Sidney Titus Iii
Dissertations and Theses
A computer technique for interpreting geophysical logs of drill-holes in quantitative lithologic terms has been developed and tested on the deposits of the late Eocene Coaledo Formation, a well-studied fluvio-deltaic complex in southwestern Oregon. The technique involves the use of induced and natural gamma logs for separation of coal and claystone from coarse-grained detrital rocks and the use of the ratio of resistivity and natural gamma responses (defined here as the "grain size index") to divide the coarse elastic rocks into a series of textural classes corresponding to the Wentworth-Odden particle size scale.
Formation And Zonation Of Ferruginous Bauxite Deposits Of The Chapman Quadrangle, Oregon, Richard Charles Marty
Formation And Zonation Of Ferruginous Bauxite Deposits Of The Chapman Quadrangle, Oregon, Richard Charles Marty
Dissertations and Theses
Two major theories have been advanced to account for the scattered distribution of ferruginous bauxite deposits. Original workers proposed that ferruginous bauxite originally developed over all exposed Columbia River Basalt in western Oregon and was subsequently removed by erosion. Studies which followed have suggested that it may be locally favorable conditions, especially of drainage, which are responsible for deposit distribution. Field mapping in the Chapman Quadrangle shows a possible correlation between a series of sheared zones, which may have improved drainage, and the distribution of ferruginous bauxite deposits. Examination of the pisolitic zone ferruginous bauxite of the Chapman Quadrangle failed …
The Stratigraphic Relationships Of The Columbia River Basalt Group In The Lower Columbia River Gorge Of Oregon And Washington, Terry Leo Tolan
The Stratigraphic Relationships Of The Columbia River Basalt Group In The Lower Columbia River Gorge Of Oregon And Washington, Terry Leo Tolan
Dissertations and Theses
The purpose of this study was to produce a detailed geologic map of the CRBG in the western portion of the Columbia River Gorge (fig. 1). The objectives were (1) to identify and delineate the extent of the Priest Rapids Member and Pomona Member intracanyon flows, and (2) to define the relationship of post-CRBG units to the CRBG intracanyon flows.
Stratigraphy, Structure, And Petrology Of The Snoqualmie Pass Area, Washington, Lawrence A. Chitwood
Stratigraphy, Structure, And Petrology Of The Snoqualmie Pass Area, Washington, Lawrence A. Chitwood
Dissertations and Theses
The Snoqualmie pass area lies about 50 mi (80 km) east of Seattle, Washington, along the crest of the Cascade Range. Five stratified units, forming a composite section over 22,000 ft (6700 m) thick, are recognized in the area. They were deformed and later intruded by granodiorite and quartz monzonite porphyry of the Snoqualmie batholith (middle Miocene). The oldest unit, the Denny Formation (Permian), 7000 ft (2100 m) thick, consists of interstratified basalt, andesite and dacite volcanic rocks and limestone and chert beds. This formation is unconformably overlain by a thick conformable sequence of early Tertiary strata which are subdivided, …
A Mineralogical And Geochemical Study Of The Ferruginous Bauxite Deposits In Columbia County, Oregon, And Wahkiakum County, Washington, Ronald Laverne Jackson
A Mineralogical And Geochemical Study Of The Ferruginous Bauxite Deposits In Columbia County, Oregon, And Wahkiakum County, Washington, Ronald Laverne Jackson
Dissertations and Theses
Wet chemical analysis and instrumental neutron activation analysis (INAA) were performed on a suite of samples from three residual ferruginous bauxite profiles in the study area for abundances of Al2O3,
SiO2, Fe2O3, Ti O2, Na, Sc, Hf, Cr, Co, La, Sm, Yb, Lu, and Th. In addition a mineralogical study accompanied this research, using petrographic, differential thermal, and x-ray diffraction techniques. In each profile, the relative mobility of these elements were calculated by empirical methods for comparison with the parent rock and mineral properties in the saprolite.
This …
Environmental Geology Of The Marquam Hill Area, Roger Alan Redfern
Environmental Geology Of The Marquam Hill Area, Roger Alan Redfern
Dissertations and Theses
This work on Marquam Hill area in Portland, a relatively undeveloped urban hillside area, is a pilot study in which environmental factors are evaluated quantitatively in order to delineate limitations on development. The study was undertaken at the request of and in cooperation with the City of Portland Planning Commission and with the State of Oregon Department of Geology and Mineral Industries. Factors considered include various aspects of the land, vegetation and attitudes of inhabitants. Findings are not intended to satisfy need for individual site studies by qualified experts but should show where that expertise is needed.
Field data were …
Geophysical And Geological Analysis Of A Fault-Like Linearity In The Lower Clackamas River Area, Clackamas County, Oregon, Ronald Jay Schmela
Geophysical And Geological Analysis Of A Fault-Like Linearity In The Lower Clackamas River Area, Clackamas County, Oregon, Ronald Jay Schmela
Dissertations and Theses
A fault-like linearity along the lower Clackamas River is evaluated by analysis of physiographic and structural alignments, geological relationships, and by gravity and magnetic data. The study has resulted in the verification of a structural feature extending along the Clackamas River and the eastern front of the Portland Hills.
Physiographic alignments were examined in twelve 15 minute and two 7-1/2 minute quadrangle maps. A significant northeasterly morphologic trend, N. 20⁰ W. and N. 40° W., and other secondary trends, namely, the N-S, E-W, and N. 50-60° E., has developed in the Portland area. The consistent northwest trend is observed throughout …