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Compositional And Physical Gradients In The Magmas Of The Devine Canyon Tuff, Eastern Oregon: Constraints For Evolution Models Of Voluminous High-Silica Rhyolites, Shelby Lee Isom 2017 Portland State University

Compositional And Physical Gradients In The Magmas Of The Devine Canyon Tuff, Eastern Oregon: Constraints For Evolution Models Of Voluminous High-Silica Rhyolites, Shelby Lee Isom

Dissertations and Theses

Large-volume silicic ignimbrites erupt from reservoirs that vary in composition, temperature, volatile content and crystallinity. The 9.7 Ma Devine Canyon Tuff (DCT) of eastern Oregon is a large-volume (>250 km3), compositionally zoned and variably welded ignimbrite. The ignimbrite exhibits heterogeneous trace element compositions, variable volatile content and crystallinity. These observations were utilized in the investigation into the generation, accumulation and evolution of the magmas composing the DCT. Building off previous research, pumices were selected from the range of trace element compositions and analyzed with respect to crystallinity, mineral abundances and assemblages. The DCT displays a gradational trace element enrichment ...


Reference Data Set Of Volcanic Ash Physicochemical And Optical Properties, A. Vogel, S. Diplas, A. J. Durant, A. S. Azar, M. F. Sunding, William I. Rose, A. Sytchkova, C. Bonadonna, K. Krüger, A. Stohl 2017 Norwegian Institute of Air Research

Reference Data Set Of Volcanic Ash Physicochemical And Optical Properties, A. Vogel, S. Diplas, A. J. Durant, A. S. Azar, M. F. Sunding, William I. Rose, A. Sytchkova, C. Bonadonna, K. Krüger, A. Stohl

Department of Geological and Mining Engineering and Sciences Publications

Uncertainty in the physicochemical and optical properties of volcanic ash particles creates errors in the detection and modeling of volcanic ash clouds and in quantification of their potential impacts. In this study, we provide a data set that describes the physicochemical and optical properties of a representative selection of volcanic ash samples from nine different volcanic eruptions covering a wide range of silica contents (50–80 wt % SiO2). We measured and calculated parameters describing the physical (size distribution, complex shape, and dense-rock equivalent mass density), chemical (bulk and surface composition), and optical (complex refractive index from ultraviolet to near-infrared ...


Melting In The Mantle Wedge: Quantifying The Effects Of Crustal Morphology And Viscous Decoupling On Melt Production With Application To The Cascadia Subduction Zone, Jiaming Yang 2017 Portland State University

Melting In The Mantle Wedge: Quantifying The Effects Of Crustal Morphology And Viscous Decoupling On Melt Production With Application To The Cascadia Subduction Zone, Jiaming Yang

Dissertations and Theses

Arc magmatism is sustained by the complex interactions between the subducting slab, the overriding plate, and the mantle wedge. Partial melting of mantle peridotite is achieved by fluid-induced flux melting and decompression melting due to upward flow. The distribution of melting is sensitive to temperature, the pattern of flow, and the pressure in the mantle wedge. The arc front is the surface manifestation of partial melting in the mantle wedge and is characterized by a narrow chain of active volcanoes that migrate in time. The conventional interpretation is that changes in slab dip angle lead to changes in the arc ...


Desert Pool {If Every Desert Was Once A Sea}, Karen Miranda Abel 2017 York University

Desert Pool {If Every Desert Was Once A Sea}, Karen Miranda Abel

The Goose

Desert Pool {If every desert was once a sea} is a site-specific art project by Canadian artist Karen Miranda Abel completed in 2016 while artist-in-residence at Joya: arte + ecología, an arts-led research centre situated in an alpine desert within a national park in southern Spain. The elemental installation represents an envisioning of the ancient sea that occupied the Sierra de María-Los Vélez Natural Park millions of years before the current desert ecology, a time when its highest mountain peaks may have been islands.


Field Mapping Investigation And Geochemical Analysis Of Volcanic Units Within The Dinner Creek Tuff Eruptive Center, Malheur County, Eastern Oregon, Matthew Cruz 2017 Portland State University

Field Mapping Investigation And Geochemical Analysis Of Volcanic Units Within The Dinner Creek Tuff Eruptive Center, Malheur County, Eastern Oregon, Matthew Cruz

Dissertations and Theses

The Dinner Creek Tuff is a mid-Miocene rhyolitic to dacitic ignimbrite, consisting of four cooling units with 40Ar/39Ar ages 16--15 Ma. Previous geologists have suspected that the source of the tuff is located in northwestern Malheur County, eastern Oregon. This broad area is called the Dinner Creek Tuff Eruptive Center.

This thesis summarizes field work, XRF/ICP-MS geochemistry, thin section petrography, and SEM feldspar analysis from the summers of 2015 and 2016. The main purpose of this study is to identify sources for the Dinner Creek Tuff units within the Dinner Creek Tuff Eruptive Center. The secondary purpose is ...


Collaborative Research: Facet: Quantifying The Topographic Response To Tectonic Processes In Southern Taiwan, Tammy M. Rittenour 2017 Utah State University

Collaborative Research: Facet: Quantifying The Topographic Response To Tectonic Processes In Southern Taiwan, Tammy M. Rittenour

Funded Research and Data

No abstract provided.


Coastal Eolian Sand-Ramp Development Related To Paleo-Sea-Level Changes During The Latest Pleistocene And Holocene (21–0 Ka) In San Miguel Island, California, U.S.A., Curt D. Peterson, Jon M. Erlandson, Errol Stock, Steve W. Hostetler, David M. Price 2017 Portland State University

Coastal Eolian Sand-Ramp Development Related To Paleo-Sea-Level Changes During The Latest Pleistocene And Holocene (21–0 Ka) In San Miguel Island, California, U.S.A., Curt D. Peterson, Jon M. Erlandson, Errol Stock, Steve W. Hostetler, David M. Price

Geology Faculty Publications and Presentations

Coastal eolian sand ramps (5–130 m elevation) on the northern slope (windward) side of the small San Miguel Island (13 km in W-E length) range in age from late Pleistocene to modern time, though a major hiatus in sand-ramp growth occurred during the early Holocene marine transgression (16–9 ka). The Holocene sand ramps (1–5 m measured thicknesses) currently lack large dune forms, thereby representing deflated erosional remnants, locally covering thicker late Pleistocene sand-ramp deposits. The ramp sand was initially supplied from the adjacent island-shelf platform, extending about 20 km north of the present coastline. The sand-ramp deposits ...


Anthropogenic Infilling Of A Bermudian Sinkhole And Its Impact On Sedimentation And Benthic Foraminifera In The Adjacent Anchialine Cave Environment, Jacquelyn N. Cresswell, Peter J. van Hengstum, Thomas M. Iliffe, Bruce E. Williams, Gil Nolan 2017 Texas A&M University at Galveston

Anthropogenic Infilling Of A Bermudian Sinkhole And Its Impact On Sedimentation And Benthic Foraminifera In The Adjacent Anchialine Cave Environment, Jacquelyn N. Cresswell, Peter J. Van Hengstum, Thomas M. Iliffe, Bruce E. Williams, Gil Nolan

International Journal of Speleology

In the mid-20th century, an inland brackish pond from Bermuda, known as Eve’s Pond, was filled with marine sediment from an adjacent coastal lagoon. At this time, an eyewitness reported “…sediment billowing out of the Green Bay Cave for days…”, which is a marine-dominated anchialine cave located proximal to the former location of Eve’s Pond (~200 m). The purpose of this study was to evaluate the potential impact of this infilling event on cave sedimentation and benthic meiofaunal communities, as proxied by the unicellular protists foraminifera that remain preserved in the sediment record. Eight sediment cores were ...


Holdrege: Nebraska's State Soil, University of Nebraska - Lincoln 2017 University of Nebraska - Lincoln

Holdrege: Nebraska's State Soil, University Of Nebraska - Lincoln

Conservation and Survey Division

No abstract provided.


Holdrege Nebraska State Soil, Nebraska Society of Professional Soil Scientists 2017 Nebraska Society of Professional Soil Scientists

Holdrege Nebraska State Soil, Nebraska Society Of Professional Soil Scientists

Conservation and Survey Division

No abstract provided.


Groundwater Levels In Nebraska 1984, Michael J. Ellis, Darryll T. Pederson 2017 U.S. Geological Survey

Groundwater Levels In Nebraska 1984, Michael J. Ellis, Darryll T. Pederson

Conservation and Survey Division

No abstract provided.


Estimation Of Total Dissolved Solid In Groundwater Using Multiple Linear Regression Analysis Around Igando Dumpsites In Lagos, South-West, Nigeria, Anthony A. Ameloko, Elijah A. Ayolabi 2017 Convenant University, Ota, Nigeria

Estimation Of Total Dissolved Solid In Groundwater Using Multiple Linear Regression Analysis Around Igando Dumpsites In Lagos, South-West, Nigeria, Anthony A. Ameloko, Elijah A. Ayolabi

Confluence Journal of Environmental Studies (CJES), Kogi State University, Nigeria

This study presents a multiple linear regression (MLR) TDS model that relates the TDS data obtained from groundwater samples to the geophysical data obtained from Electromagnetic (EM) data, as an alternative approach to mapping and monitoring the impact of TDS in groundwater. The predictive power of the developed MLR TDS model was appraised to determine the feasibility of using the TDS model to predict groundwater TDS around the study area. Although, the accuracy of the developed TDS model is site specific, the EM data around the area can be applied to the model to determine TDS concentration in groundwater, thus ...


Sulfur-Based Speleogenesis In The Cumberland Plateau, Usa, Lee J. Florea 2017 Ball State University

Sulfur-Based Speleogenesis In The Cumberland Plateau, Usa, Lee J. Florea

Lee J Florea, PhD, P.G.

No abstract provided.


Throughfall Nutrients In A Degraded Indigenous Fagus Orientalis Forest And A Picea Abies Plantation In The Of North Of Iran, Parisa Abbasian, Pedram Attarod, Seyed Mohammad Moein Sadeghi, John T. Van Stan, Seyed M. Hojjati 2017 University of Tehran

Throughfall Nutrients In A Degraded Indigenous Fagus Orientalis Forest And A Picea Abies Plantation In The Of North Of Iran, Parisa Abbasian, Pedram Attarod, Seyed Mohammad Moein Sadeghi, John T. Van Stan, Seyed M. Hojjati

John T. Van Stan II

Aim of study: The objective of this study was to compare the quantity and quality of TF (throughfall) in an indigenous, but degraded, stand of Fagus orientalis and Picea abies plantation. Area of study: Forests of Kelar-Dasht region located in Mazandaran province, northern Iran. Material and Methods: TF measured by twenty collectors that were distributed randomly underneath each stand. For 21 storms sampled in 2012 (August-December) and 2013 (April-June), we analyzed pH, EC, Ca2+, Mg2+, K+, NO3-, and P of gross rainfall (GR) and TF. Main results: Cumulative interception (I) for F. orientalis and P. abies were 114.2 mm ...


Soputan Volcano, Indonesia: Petrological Systematics Of Volatiles And Magmas And Their Bearing On Explosive Eruptions Of A Basalt Volcano, Syegi Lenarahmi Kunrat 2017 Portland State University

Soputan Volcano, Indonesia: Petrological Systematics Of Volatiles And Magmas And Their Bearing On Explosive Eruptions Of A Basalt Volcano, Syegi Lenarahmi Kunrat

Dissertations and Theses

Soputan volcano is one of the few basaltic volcanoes among 127 active volcanoes in Indonesia. It is part of the Sempu-Soputan volcanic complex located south of Tondano Caldera, North Sulawesi and commonly produces both explosive eruptions with VEI 2-3 and effusive lava dome and flow eruptions. Over the last two decades, Soputan had thirteen eruptions, the most recent in 2016. Most eruptions started explosively, followed by dome growth and in some cases pyroclastic flows. Our study focuses on understanding the magmatic system of Soputan and what processes are responsible for its highly explosive eruptions, which are typically uncommon for a ...


Molecular And Optical Properties Of Tree-Derived Dissolved Organic Matter In Throughfall And Stemflow From Live Oaks And Eastern Red Cedar, Aron Stubbins, Leticia M. Silva, Thorsten Dittmar, John T. Van Stan 2017 University of Georgia

Molecular And Optical Properties Of Tree-Derived Dissolved Organic Matter In Throughfall And Stemflow From Live Oaks And Eastern Red Cedar, Aron Stubbins, Leticia M. Silva, Thorsten Dittmar, John T. Van Stan

John T. Van Stan II

Studies of dissolved organic matter (DOM) transport through terrestrial aquatic systems usually start at the stream. However, the interception of rainwater by vegetation marks the beginning of the terrestrial hydrological cycle making trees the headwaters of aquatic carbon cycling. Rainwater interacts with trees picking up tree-DOM, which is then exported from the tree in stemflow and throughfall. Stemflow denotes water flowing down the tree trunk, while throughfall is the water that drips through the leaves of the canopy. We report the concentrations, optical properties (light absorbance) and molecular signatures (ultrahigh resolution mass spectrometry) of tree-DOM in throughfall and stemflow from ...


Geology And Geochemistry Of The Uvas Volcanic Field And Rubio Peak Formation Of South-Central New Mexico, Usa, Max Logan Hoffman 2017 Missouri State University

Geology And Geochemistry Of The Uvas Volcanic Field And Rubio Peak Formation Of South-Central New Mexico, Usa, Max Logan Hoffman

MSU Graduate Theses

South-central New Mexico is characterized by many Cenozoic volcanic and tectonic events that produced a complex system of magma sources. These mechanisms are responsible for the diverse volcanic activity and magmatic evolution in New Mexico. To understand the growth and development of the mantle sources associated with these events, geochemical, petrographic, structural and spatial distribution data were collected from the Uvas volcanic field (UVF) and the Rubio Peak Formation of the Mogollon-Datil volcanic field (MDVF). Volcanic rocks from these volcanic fields were chosen based on their importance to relative timing of magmatic and tectonic transitioning events. The structural and spatial ...


The Dynamic Relationship Between The Bear River, Quaternary Basaltic Center, Normal Faults, And The Resulting Rearrangement Of Rivers In The Northeast Edge Of The Great Basin, Southeast Idaho, Brady Utley 2017 Utah State University

The Dynamic Relationship Between The Bear River, Quaternary Basaltic Center, Normal Faults, And The Resulting Rearrangement Of Rivers In The Northeast Edge Of The Great Basin, Southeast Idaho, Brady Utley

All Graduate Plan B and other Reports

The objective of this research project in Gem Valley graben, southeast Idaho is to identify the location, age and history of the Quaternary diversion of the Bear River into paleo-Lake Thatcher, and then into the Lake Bonneville basin from the Columbia River basin. Mapping, geochemical analysis, cross-cutting relationships, and five new age determinations, together with prior published research, shed new light on the complex history of interaction between the volcanic rocks, rivers, lakes, and faults in Gem Valley. Research goals were to test the hypothesis that local faulting and volcanism drove the diversion of the Bear River and controlled the ...


Stratigraphy, Petrology, And Paleontology Of The Late Cretaceous (Campanian) Mesaverde Group In Northeastern Utah, Christopher Ward 2017 Utah State University

Stratigraphy, Petrology, And Paleontology Of The Late Cretaceous (Campanian) Mesaverde Group In Northeastern Utah, Christopher Ward

All Graduate Plan B and other Reports

This project examines a poorly studied sandstone ridge called Snake John Reef located 22 miles southeast of Vernal, in northeastern Utah. Previously this ridge was mapped as exposures of late Cretaceous, undifferentiated Mesaverde Group, and recently unidentified dinosaur fossils have been found along the ridge by the Utah Field House of Natural History State Park Museum. Stratigraphic sections, petrographic thin sections, and collection and study of fossils from Snake John Reef were undertaken to understand the stratigraphic relationship as well as to reconstruct the depositional environment of the dinosaur bearing units. Snake John Reef represents exposures of three late Cretaceous ...


On The Pursuit Of Relevance In Standards-Based Curriculum Development: The Ccny Approach, Angelo Lampousis 2017 CUNY City College

On The Pursuit Of Relevance In Standards-Based Curriculum Development: The Ccny Approach, Angelo Lampousis

Publications and Research

The Society for Standards Professionals (SES) has a significant history of documenting the use of standards in research and academia. For instance, during the 62nd Annual SES Conference in 2013 in Savannah, Georgia, the author participated in such a session highlighting examples of relationships between academic institutions, government, and standards developing organizations. In this article, we attempt to capture the current advances made from similar relationships specific to our home institution, the City College of New York (CCNY) of the City University of New York (CUNY.) These advances have become possible through a grant issued under the Standards Services Curricula ...


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