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Articles 241 - 270 of 343

Full-Text Articles in Earth Sciences

Geochemical Evolution Of Ferruginous Bauxite Deposits In Northwestern Oregon And Southwestern Washington, Joseph Michael Fassio Jun 1990

Geochemical Evolution Of Ferruginous Bauxite Deposits In Northwestern Oregon And Southwestern Washington, Joseph Michael Fassio

Dissertations and Theses

Ferruginous bauxite deposits developed from flows of the Columbia River Basalt Group in northwestern Oregon and southwestern Washington. Samples of the iron pisolite and the gibbsite nodular zones from the upper portion of the weathering profile of drill core from Columbia County, Oregon and Cowlitz County, Washington, were analyzed by instrumental neutron activation. The mineralogy was determined using Xray diffraction and Mossbauer spectroscopy.

The gibbsite nodular zone is above the clay-rich saprolite or relic basalt zone. The nodules contain relic vesicles and well preserved relic plagioclase microlites. Gibbsite occurs with poorly crystalline goethite and hematite in the gibbsite nodular zone. …


Analysis And Numerical Simulation Of The Ground Water System At The Bonneville Navigation Lock Site, Oregon, Dirk Baron Jan 1990

Analysis And Numerical Simulation Of The Ground Water System At The Bonneville Navigation Lock Site, Oregon, Dirk Baron

Dissertations and Theses

As part of the new navigation lock for Bonneville Dam a new water source for the Bonneville Fish Hatchery must be supplied. The hatchery is located on the Oregon side of the Columbia River downstream of the dam. It requires large quantities of water free from chemical and biological contamination. In addition, the water has to be in a narrow temperature range. Currently the fish hatchery receives its water from a well field that is located on the alluvial terrace downstream of Bonneville Dam. The well field lies in the proposed approach channel for the new lock and has to …


Subsurface And Geochemical Stratigraphy Of Northwestern Oregon, Olga Berenice Lira Jan 1990

Subsurface And Geochemical Stratigraphy Of Northwestern Oregon, Olga Berenice Lira

Dissertations and Theses

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 …


Slope Stability As Related To Geology At Rainier, Columbia County, Oregon, James Douglas Gless Jan 1989

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.


Sediment Dynamics On The Shore Slopes Of The Puget Island Reach Of The Columbia River, Oregon And Washington, Timothy Abbe Jan 1989

Sediment Dynamics On The Shore Slopes Of The Puget Island Reach Of The Columbia River, Oregon And Washington, Timothy Abbe

Dissertations and Theses

Water waves generated by wind and ships; ebb tidal currents; water level fluctuations; and dredging impact sediment transport in shallow water of the lower Columbia River. Observations were made over a one-year period after sand dredged from the navigation channel was placed at three study sites in the Puget Island region, 46°15'N 123°25'W, Oregon and Washington. Sediment composition is fine to medium grained, low density dacitic volcanics with small percentages of pumice, heavy minerals, and basalt.


Stratigraphy, Diagenesis, And Depositional Environment Of The Cowlitz Formation (Eocene), Northwest Oregon, Leonard Carl Farr Jr. Jan 1989

Stratigraphy, Diagenesis, And Depositional Environment Of The Cowlitz Formation (Eocene), Northwest Oregon, Leonard Carl Farr Jr.

Dissertations and Theses

The Upper Eocene Cowlitz Formation is exposed in surface outcrops southwest of the town of Vernonia, in Columbia County, Oregon. The Cowlitz Formation also occurs in the subsurface of the Mist gas field where its Clark and Wilson (C and W) sandstone member (informal) acts as a natural gas reservoir, and its upper Cowlitz mudstone member (informal) acts as a cap rock. Surface exposures and continuous core were studied in order to determine Cowlitz Formation stratigraphy, and its depositional environment. Fresh core samples were also studied petrographically, and with a scanning electron microscope, in order to determine the effects of …


Dynamics Of Intermediate-Size Stream Outlets, Northern Oregon Coast, Ellen Eberhardt Oct 1988

Dynamics Of Intermediate-Size Stream Outlets, Northern Oregon Coast, Ellen Eberhardt

Dissertations and Theses

This study measured and evaluated the relation of coastal foredune morphology to stream beach outlets, and investigated the processes associated with the stream outlet. Intermediate-size streams were studied, and defined as those that flow across the beach most of the year but have no tidal influence. Fifty-four of these streams were found along the northern Oregon coast between the Columbia River and Yaquina Bay. Crescent Lake Outlet, Saltair Creek and Daley Lake Outlet were chosen as study streams for further investigation.


A Geochemical Study Of The Eagle Creek Formation In The Columbia River Gorge, Oregon, Rachel Ann Carlin Jun 1988

A Geochemical Study Of The Eagle Creek Formation In The Columbia River Gorge, Oregon, Rachel Ann Carlin

Dissertations and Theses

The Early Miocene Eagle Creek Formation, a series of volcanic mudflows and debris flows, is exposed in the Columbia River Gorge about 64 kilometers east of Portland, Oregon. Eighty-seven samples were analyzed using instrumental neutron activation analysis for trace element concentrations. Eleven samples were analyzed by Dr. Peter Hooper at Washington State University using X-ray Fluorescence for major element chemistry. These data were used to determine that the Eagle Creek Formation compositionally ranges from andesite to dacite.


Geochemical Stratigraphy Of The Dooley Rhyolite Breccia And Tertiary Basalts In The Dooley Mountain Quadrangle, Oregon, David Neale Whitson May 1988

Geochemical Stratigraphy Of The Dooley Rhyolite Breccia And Tertiary Basalts In The Dooley Mountain Quadrangle, Oregon, David Neale Whitson

Dissertations and Theses

The Dooley Rhyolite Breccia in northeast Oregon was erupted between 12 and 16 million years ago, from central vents and linear feeder dikes within the Dooley Mountain quadrangle. The peraluminous, high-silica rhyolites of the formation were erupted over an irregular highland of eroded pre-Tertiary metamorphic rocks locally overlain by intracanyon, Eocene Clarno-type basalt flow(s). The Dooley Rhyolite Braccia is exposed in a tectonically disrupted, north-south trending graben across the Elkhorn Range. The formation is variable in thickness with maximum thickness exceeding 660 meters in the south and 600 meters in the north half of the quadrangle. Volumetrically the formation is …


Rock Slope Stability Studies In Siskiyou National Forest, Greg Visconty Jan 1988

Rock Slope Stability Studies In Siskiyou National Forest, Greg Visconty

Dissertations and Theses

The line mapping method of Piteau and Martin (1977) was tested on two different rock type road cuts in the Siskiyou National Forest, and was found to be an efficient means of collecting geological data for rock slope stability analysis. The unbiased approach of this method calls for close scrutiny of the outcrops in question, covering more ground than other methods in less time. In turn, this close attention to every crack in the outcrop reveals more about the stability of the slope, and can reveal hidden hazards of rock fall.

The supportive systems for analyzing the data - stereonets …


Metasomatism Between Amphibolite And Metaultramafic Rocks During Upper Amphibolite Facies Metamorphism, Tobacco Root Mountains, Southwest Montana, William Robert Mcculloch Jan 1988

Metasomatism Between Amphibolite And Metaultramafic Rocks During Upper Amphibolite Facies Metamorphism, Tobacco Root Mountains, Southwest Montana, William Robert Mcculloch

Dissertations and Theses

The purpose of this study is to characterize the metasomatism that has taken place as a result of the chemical incompatibility between mafic and metaultramafic bulk compositions during high-grade regional metamorphism in the Tobacco Root Mountains, southwest Montana. Metasomatism of these rocks took place by both diffusionand infiltration-dominated processes. The result of these processes are characterized mineralogically and geochemically in the rocks.


Classifying Oregon Lake-Watershed Ecosystems For Regional Water Resources Assessment, Randall Alan Jones Oct 1987

Classifying Oregon Lake-Watershed Ecosystems For Regional Water Resources Assessment, Randall Alan Jones

Dissertations and Theses

Natural lake-watershed ecosystems in Oregon compose a diverse and valuable assemblage of land and water resources. With an increasing demand on lakes for recreation, water supplies, and aesthetic values and an increase in available data on Oregon lake systems, there is a need for applicable and timely scientific water management information about lake conditions statewide. This thesis is an attempt to summarize some of the data collected on natural Oregon lake-watershed ecosystems.

The purpose of the thesis is to identify the most typical natural systems out of an initial data base of twenty-four variables, measured over ninety-eight lake-watershed ecosystems. The …


Geomorphic Character, Age And Distribution Of Rock Glaciers In The Olympic Mountains, Washington, Steven Paul Welter Aug 1987

Geomorphic Character, Age And Distribution Of Rock Glaciers In The Olympic Mountains, Washington, Steven Paul Welter

Dissertations and Theses

Rock glaciers are tongue-shaped or lobate masses of rock debris which occur below cliffs and talus in many alpine regions. They are best developed in continental alpine climates where it is cold enough to preserve a core or matrix of ice within the rock mass but insufficiently snowy to produce true glaciers. Previous reports have identified and briefly described several rock glaciers in the Olympic Mountains, Washington, but no detailed integrative study has been made regarding the geomorphic character, age, and distribution of these features.

The purpose of this study is two-fold. First, surface sediment fabric analysis and relative and …


Explosion Structures In Grande Ronde Basalt Of The Columbia River Basalt Group, Near Troy, Oregon, Leonard Lee Orzol Jun 1987

Explosion Structures In Grande Ronde Basalt Of The Columbia River Basalt Group, Near Troy, Oregon, Leonard Lee Orzol

Dissertations and Theses

Explosion structures occur in flows of Grande Ronde Basalt in the study area near Troy, Oregon. Data from nineteen stratigraphic sites indicate that the maximum number of flows that contain explosion structures at any one site is six. In the informally named Troy flow, explosion structures are widespread.

Each flow that contains explosion structures can be divided into two cooling units. The first cooling units occupy troughs in the pre-eruption topography and are up to 10 meters thick. The second cooling units contain the explosion structures and are up to 100 meters thick. The thickness of flows that contain explosion …


Stratigraphic And Geochemical Evolution Of The Glass Buttes Complex, Oregon, Richard Louis Roche Jan 1987

Stratigraphic And Geochemical Evolution Of The Glass Buttes Complex, Oregon, Richard Louis Roche

Dissertations and Theses

Glass Buttes complex lies at the northern margin of the Basin and Range province in central Oregon and is cut by the northwest-trending Brothers fault zone. An older acrystalline volcanic sequence of high-silica rhyolites (>75% SiO2) forms a broad platform composed of domes and flows with minor pyroclastic deposits. The high-silica rhyolite sequence is divided on the basis of texture into 1) zoned flows and domes, 2) obsidian flows, 3) felsite flows, and 4) biotite-phyric flows and domes.


Textural And Mineralogical Characteristics Of Altered Grande Ronde Basalt, Northeastern Oregon : A Natural Analog For A Nuclear Waste Repository In Basalt, Paul M. Trone Jan 1987

Textural And Mineralogical Characteristics Of Altered Grande Ronde Basalt, Northeastern Oregon : A Natural Analog For A Nuclear Waste Repository In Basalt, Paul M. Trone

Dissertations and Theses

Altered flows that are low-MgO chemical types of the Grande Ronde Basalt crop out in the steep walls of the Grande Ronde River canyon near Troy, Wallowa County, Oregon. The alteration effects in these flows are being investigated as a natural analog system to a high level nuclear waste repository in basalt. The flows within the study are referred to as the analog flow, in which the alteration effects are the strongest, and the superjacent flow. The analog flow crops out at Grande Ronde River level and a roadcut-outcrop is developed in the flow-top breccia of this flow. The two …


Stratigraphic Model Of The Southern Portion Of The Jim Bridger Coal Field, Sweetwater County, Wyoming, Paul S. Maywood Jan 1987

Stratigraphic Model Of The Southern Portion Of The Jim Bridger Coal Field, Sweetwater County, Wyoming, Paul S. Maywood

Dissertations and Theses

Uppermost Lance and lowermost Fort Union Formation sediments are found in outcrop in the southern portion of the Jim Bridger coal field, located on the northeast flank of the Rock Springs Uplift in Sweetwater County, Wyoming. Twenty-nine surface sections and 581 subsurface (borehole) sections were evaluated and used to construct a stratigraphic model.

Stratigraphic correlations with economically mineable coal seams in the Fort Union Formation north and south of the study area combined with definition of questionable local formational boundary locations are significant objectives in this investigation.


A Seismic Refraction Study Of A Portion Of The Northeastern Margin Of The Tualatin Valley, Oregon, David John Nazy Jan 1987

A Seismic Refraction Study Of A Portion Of The Northeastern Margin Of The Tualatin Valley, Oregon, David John Nazy

Dissertations and Theses

The Tualatin Valley is a well defined elliptical basin centered at Hillsboro, with a major axis trending roughly N65°W. The valley is bordered on the northeast by the Tualatin Mountains (Portland Hills) which are a faulted, northwest-trending asymmetrical anticline. Topographic and geophysical evidence have defined the Portland Hills fault, which occurs along the northeast side of the Tualatin Mountains. The possibility that a fault or fault zone occurs along the southwest side of the Tualatin Mountains was investigated in this study.


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 Jan 1987

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.


Stratigraphy Of The Ohanapecosh Formation North Of Hamilton Buttes, Southcentral Washington, Cynthia Marie Stine Jan 1987

Stratigraphy Of The Ohanapecosh Formation North Of Hamilton Buttes, Southcentral Washington, Cynthia Marie Stine

Dissertations and Theses

Over 1055 m of early Oligocene andesitic-dacitic volcaniclastic rocks and minor interbedded andesitic lava flows of the Ohanapecosh Formation are exposed in a dissected structural high in the southern Washington Cascade Range, about 22 km southwest of Packwood, Washington.

The exposed sequence of rocks in the study area are located approximately 250 m above the base of the Ohanapecosh Formation. A lower sequence of deposits, about 350 m in thickness, are dominated by primary and reworked lithic lapilli-tuff and epiclastic channelized volcanic sandstone and conglomerate. These sediments are interpreted as pyroclastic flows and stream deposits, respectively. The upper sequence, about …


An Analysis Of The Eastern Margin Of The Portland Basin Using Gravity Surveys, Steven Allen Davis Jan 1987

An Analysis Of The Eastern Margin Of The Portland Basin Using Gravity Surveys, Steven Allen Davis

Dissertations and Theses

The recent contributions of several investigators has indicated the Portland basin may be a pull-apart structure associated with wrench tectonism. Because of the large density contrast between sedimentary and volcanic units and because of their reasonably uniform and continuous nature, gravity survey methods can be used to identify covered structures with considerable success. The study utilized gravity modeling techniques to investigate the structure and genesis of the Portland basin's eastern margin.


A Groundwater Flow Model Of The Aquifer Intercommunication Area, Hanford Site, Washington, Elizabeth G. Simkover Dec 1986

A Groundwater Flow Model Of The Aquifer Intercommunication Area, Hanford Site, Washington, Elizabeth G. Simkover

Dissertations and Theses

Intercommunication has been identified between the unconfined and uppermost confined aquifer systems underlying a portion of the U.S. Department of Energy's Hanford Site. Erosional thinning and fracturing of the basalt confining layer within the study area allows physical contact between the two aquifers, but the vertical hydraulic gradient (a required driving force) is small. To better conceptualize the distribution and volume of the leakage occurring between the aquifer systems, this study investigates the confined Rattlesnake Ridge Aquifer flow system, which appears to be more sensitive to the vertical leakage than the overlying unconfined aquifer.

The flow system of the Rattlesnake …


Geology Of The Willamette Pass Area, Cascade Range, Oregon, Neil M. Woller Nov 1986

Geology Of The Willamette Pass Area, Cascade Range, Oregon, Neil M. Woller

Dissertations and Theses

The Willamette Pass area is situated at the intersection of two hypothesized structural features, the Western Cascade-High Cascade boundary and the Eugene-Denio lineament. It is of interest due to its designation by the U.S. Department of the Interior as a Known Geothermal Resource Area.

Volcanic rocks of Oligocene to Pleistocene age are exposed in the study area. The oldest rocks are the Oligocene-Miocene lavas, undifferentiated, which are a diverse unit of ignimbrites and intermediate to silicic flows. The Oligocene-Miocene rhyodacites are a stratigraphically equivalent unit which is predominantly composed of aphyric rhyodacite flows. Middle Miocene volcanism produced the basaltic lavas …


Tephrostratigraphy Of The Middle Eocene Chumstick Formation, Cascade Range, Douglas County, Washington, Matthew John Mcclincy Jul 1986

Tephrostratigraphy Of The Middle Eocene Chumstick Formation, Cascade Range, Douglas County, Washington, Matthew John Mcclincy

Dissertations and Theses

This study outlines the ash (tuff) bed stratigraphy (tephrostratigraphy) in the middle Eocene Chumstick Formation of central Washington. The tuff beds provide local marker beds enabling interpretation of the stratigraphy and structure of the formation. The chemical signature of these units provides the basis on which the units can be traced over broad areas in the basin of deposition. Correlations of tuff beds were obtained over distances of 41 km.

The tephrostratigraphy of the Chumstick Formation consists of nineteen tuff marker beds. Seventeen of these units are chemically characterized in this study. Ten elements were used to fingerprint these tuff …


The Engineering Geology Of The Fountain Landslide, Hood River County, Oregon, Susanne L. D'Agnese May 1986

The Engineering Geology Of The Fountain Landslide, Hood River County, Oregon, Susanne L. D'Agnese

Dissertations and Theses

The Fountain Landslide located along I-84, five kilometers east of Cascade Locks, Oregon has moved periodically for over thirty years. Aerial photographs taken prior to recorded movement of the landslide show the headscarp of a large preexisting landslide. In 1952 a cut was made into the toe of the landslide to straighten Highway 30. The recorded movement history begins at this time. Stabilization procedures in the late 1950's focused on dewatering the slide mass. Movement had nearly stopped by 1957. A deeper cut was made into the toe of the landslide in 1966 to widen the highway to the four-laned …


The Geology And Hydrothermal Alteration Of The Bear Creek Butte Area, Crook County, Central Oregon, Richard Matthew Wilkening Apr 1986

The Geology And Hydrothermal Alteration Of The Bear Creek Butte Area, Crook County, Central Oregon, Richard Matthew Wilkening

Dissertations and Theses

The Eocene Clarno Formation, the Oligocene John Day Formation and basalts of the High Lava Plains are exposed in the Bear Creek Butte area in Central Oregon. In this area the Clarno Formation can be divided into a lower sequence composed of intermediate lava flows with intercalated mudflows and volcaniclastic sediments and an upper sequence of rhyolite and basalt flows and felsic ruffs. Separating the two units is a well developed saprolite. The change from intermediate to rhyolite-basalt volcanism reflects a change in the tectonic environment of the Cascade volcanic arc from compression to relaxation as subduction of the Farallon …


Biostratigraphy Of The Cowlitz Formation In The Upper Nehalem River Basin, Northwest Oregon, Neil B. Shaw Feb 1986

Biostratigraphy Of The Cowlitz Formation In The Upper Nehalem River Basin, Northwest Oregon, Neil B. Shaw

Dissertations and Theses

Examination of stream and roadcut exposures of the Cowlitz Formation allows the selection of measured representative sections, and collection of fossils, from an area roughly defined by the intersection of the boundaries of Clatsop, Columbia, Tillamook and Washington counties in Oregon. The study defines the features of the local environment of deposition, correlates sections to derive a composite columnar section, and develops a checklist of species for both microfossils and megafossils of the Cowlitz Formation.


Stratigraphic And Petrologic Analysis Of Trends Within The Spencer Formation Sandstones : From Corvallis, Benton County, To Henry Hagg Lake, Yamhill And Washington Counties, Oregon, Brent Joseph Cunderla Jan 1986

Stratigraphic And Petrologic Analysis Of Trends Within The Spencer Formation Sandstones : From Corvallis, Benton County, To Henry Hagg Lake, Yamhill And Washington Counties, Oregon, Brent Joseph Cunderla

Dissertations and Theses

Within the thesis study area Spencer Formation arkosic/arkosic lithic sandstone lithofacies of Narizian age crop out in a sinuous north-northwesterly band from the Corvallis area into the Henry Hagg Lake vicinity ten kilometers southwest of Forest Grove, Oregon.


The Stratigraphy Of The Scappoose Formation, The Astoria Formation, And The Columbia River Basalt Group In Northwestern Columbia County, Oregon, Nancy Tompkins Ketrenos Jan 1986

The Stratigraphy Of The Scappoose Formation, The Astoria Formation, And The Columbia River Basalt Group In Northwestern Columbia County, Oregon, Nancy Tompkins Ketrenos

Dissertations and Theses

The study area is located in northwestern Columbia County, and covers an area of approximately 70 square kilometers. The purpose of the study was to investigate the possible correlation of the Scappoose and Astoria Formations and determine their stratigraphic relationship to the Columbia River Basalt Group through mapping, geochemistry and petrography.


A Stratigraphic-Geochemical Study Of The Troutdale Formation And Sandy River Mudstone In The Portland Basin And Lower Columbia River Gorge, Rodney Duane Swanson Jan 1986

A Stratigraphic-Geochemical Study Of The Troutdale Formation And Sandy River Mudstone In The Portland Basin And Lower Columbia River Gorge, Rodney Duane Swanson

Dissertations and Theses

Hyaloclastic sediment forms an identifiable stratigraphic interval within the Troutdale Formation that can be traced from the Bridal Veil channel to the Portland basin. Hyaloclastic sediment composed chiefly vitric sands is found interbedded with muds, sandy muds and gravels penetrated by wells in northeast Portland are correlated with the upper member of the Troutdale Formation. These beds are characteristic of the informal upper member of the Troutdale Formation in the Bridal Veil channel of the ancestral Columbia River (Tolan and Beeson, 1984) and the type area of the Troutdale Formation exposed along the Sandy River (Trimble, 1963). Fluvially deposited hyaloclastic …