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Grounding Zone Processes: Ice Mechanics And Margin Lakes, Kamb Ice Stream And Whillans Ice Stream, West Antarctica, Mason Joseph Fried 2013 Portland State University

Grounding Zone Processes: Ice Mechanics And Margin Lakes, Kamb Ice Stream And Whillans Ice Stream, West Antarctica, Mason Joseph Fried

Dissertations and Theses

The lateral "corners" where Kamb and Whillans Ice Streams (KIS and WIS) discharge into the Ross Ice Shelf share common geometries and ice mechanical settings. At both corners of the now-stagnant KIS outlet, shear margins of apparently different ages confine regions with a relatively flat, smooth surface expression. These features are called the "Duckfoot" on the northern, right-lateral side and the "Goosefoot" on the other. It has been suggested, on evidence found in ice internal layers, that the flat ice terrains on KIS were afloat in the recent past, at a time when the ice stream grounding line was upstream …


Arsenic Mobility And Compositional Variability In High-Silica Ash Flow Tuffs, Courtney Beth Young Savoie 2013 Portland State University

Arsenic Mobility And Compositional Variability In High-Silica Ash Flow Tuffs, Courtney Beth Young Savoie

Dissertations and Theses

Volcanic rocks typically have only low to moderate arsenic concentrations, none-the-less, elevated levels of arsenic in ground waters have been associated with pyroclastic and volcaniclastic rocks and sediments in many parts of the world. The potential for arsenic leaching from these deposits is particularly problematic as they often comprise important water-bearing units in volcanic terrains. However, the role that chemical and mineralogical variations play in controlling the occurrence and mobility of arsenic from pyroclastic rocks is largely unexplored.

This study uses chemical and X-ray diffraction data to characterize and classify 49 samples of ash-flow tuffs, and 11 samples of tuffaceous …


Hydrogeologic Characterization Of Dutch Canyon, Scappoose, Oregon, Derrick Lee Wagner 2013 Portland State University

Hydrogeologic Characterization Of Dutch Canyon, Scappoose, Oregon, Derrick Lee Wagner

Dissertations and Theses

Dutch Canyon is located directly west of the City of Scappoose in Columbia County Oregon. This area is proximate to Highway 30, a major access corridor to downtown Portland, and is experiencing a population increase, which is expected to continue and likely accelerate. As a result, there is growing pressure on water resources. Individual and community efforts to utilize groundwater resources have been hampered by generally poor groundwater yields and water quality concerns outside of the Columbia River corridor and a lack of published hydrogeologic information for the region.

The intent of this study is to identify the water-bearing units …


Plains Co2 Reduction (Pcor) Partnership Atlas, Wesley D. Peck, Tera D. Buckley, Earl P. Battle, Megan M. Grove, Joyce M. Riske, Charles D. Gorecki, Edward N. Steadman, John A. Harju 2013 University of North Dakota. Energy and Environmental Research Center

Plains Co2 Reduction (Pcor) Partnership Atlas, Wesley D. Peck, Tera D. Buckley, Earl P. Battle, Megan M. Grove, Joyce M. Riske, Charles D. Gorecki, Edward N. Steadman, John A. Harju

EERC Maps and Infographics

The Plains CO2 Reduction (PCOR) Partnership Atlas provides a regional profile of CO2 sources and potential CO2 storage locations across the PCOR Partnership region. The revised fourth edition provides an update-to-date look at PCOR Partnership activities, including regional characterization and full-scale demonstration activities. Additional background information on carbon capture, utilization, and storage (CCUS) is included to give a better understanding of how CCUS addresses concerns about climate change while allowing future energy needs to be met.


Identification And Paleoecology Of Mammoth Teeth From The Vertebrate Paleontology Collection At The Sternberg Museum Of Natural History, Hays, Kansas, Elizabeth Deering 2013 Fort Hays State University

Identification And Paleoecology Of Mammoth Teeth From The Vertebrate Paleontology Collection At The Sternberg Museum Of Natural History, Hays, Kansas, Elizabeth Deering

Master's Theses or Doctor of Nursing Practice

Thirty-five mammoth teeth from the Vertebrate Paleontology Collection at the Sternberg Museum of Natural History in Hays, Kansas were examined to determine the species and palaeoecological association. Quantitative and qualitative descriptions of tooth length, width, height, enamel thickness, lamellar frequency, condition, shape, and size, were determined. Thirty-four of the teeth were identified as Mammuthus columbi and one was identified as M. jeffersonii, indicating that M. columbi was the dominant mammoth cycles that resulted in cool, mesic, boreal coniferous forests and prairie (steppe) environments throughout the Pleistocene. M. columbi and M. jeffersonii would have thrived in these environments and would have …


3d Seismic Analysis And Characterization Of A Stacked Turbidite Channel: Niger Delta Complex, Anthony Luna 2013 Fort Hays State University

3d Seismic Analysis And Characterization Of A Stacked Turbidite Channel: Niger Delta Complex, Anthony Luna

Master's Theses or Doctor of Nursing Practice

A stacked turbidite channel was interpreted from 3D seismic data acquired in the Niger Delta off the west coast of Africa. In offshore environments, such as the Niger Delta, submarine canyons provide a conduit for currents to transport large sediment loads to form stacked turbidites. Turbidite channels are typically convoluted deposits and contain sands that are potential reservoir targets of hydrocarbon exploration. The internal characteristics of these turbidites are often complex and difficult to interpret accurately. This study characterizes the morphology of a stacked turbidite deposit by describing key features that are commonly found in turbidite channels, including: channel sinuosity, …


Studying The Relationship Between Mud/Salt Flat Habitat And Shorebird Abundance At Two Wetland Areas Using Landsat, Dustin Reagan 2013 Fort Hays State University

Studying The Relationship Between Mud/Salt Flat Habitat And Shorebird Abundance At Two Wetland Areas Using Landsat, Dustin Reagan

Master's Theses or Doctor of Nursing Practice

The objective of this project was to determine the degree and direction of association between the amount of mud/salt flat area and shorebird abundance during spring and early summer. This study used Landsat 5 to indirectly measure mudflat and salt flat areas at two wetland complexes within Kansas over a period of several years (1991-2008). These measurements were compared to shorebird surveys conducted by several individuals at both Quivira National Wildlife Refuge and Cheyenne Bottoms Wildlife Area. A correlation analysis showed that significant relationships exist between mud/salt flat area and the abundance of certain shorebird species. Correlation coefficients for individual …


Decoupling The Stationary Navier-Stokes-Darcy System With The Beavers-Joseph-Saffman Interface Condition, Yong Cao, Yuchuan Chu, Xiaoming He, Mingzhen Wei 2013 Missouri University of Science and Technology

Decoupling The Stationary Navier-Stokes-Darcy System With The Beavers-Joseph-Saffman Interface Condition, Yong Cao, Yuchuan Chu, Xiaoming He, Mingzhen Wei

Mathematics and Statistics Faculty Research & Creative Works

This paper proposes a domain decomposition method for the coupled stationary Navier-Stokes and Darcy equations with the Beavers-Joseph-Saffman interface condition in order to improve the efficiency of the finite element method. The physical interface conditions are directly utilized to construct the boundary conditions on the interface and then decouple the Navier-Stokes and Darcy equations. Newton iteration will be used to deal with the nonlinear systems. Numerical results are presented to illustrate the features of the proposed method.


Dendrochronological Analysis Of Jones Homestead, 2013 The College of Wooster

Dendrochronological Analysis Of Jones Homestead

Historic Structures

Dating historical structures using dendrochronology. The Historical Structures collection consists of reports that are the result of dendochronological analysis of timbers from structures in Pennsylvania and Ohio. Contributors: Dilyard, Jeff; Wiesenberg, Nicholas


Microstructures And Quartz Lattice-Preferred Orientations In The Eclogite-Bearing Migmatitic Gneisses Of The D’Entrecasteaux Islands, Papua New Guinea, T. A. Little, B. R. Hacker, S. J. Brownlee, G. Seward 2013 Victoria University of Wellington

Microstructures And Quartz Lattice-Preferred Orientations In The Eclogite-Bearing Migmatitic Gneisses Of The D’Entrecasteaux Islands, Papua New Guinea, T. A. Little, B. R. Hacker, S. J. Brownlee, G. Seward

Environmental Science and Geology Faculty Research Publications

Lattice preferred orientations (LPO) of quartz in gneiss domes of the D’Entrecasteaux Islands, Woodlark Rift shed insight into exhumation of the world’s youngest (~5–7Ma) eclogite-bearing terrane at cm/yr rates. We focus on deformation that affected the terrane as it transited between lower crustal depths and the surface, including: (1) grain-scale deformation mechanisms; and (2) style of flow and mode of emplacement of the domes. Electron-backscatter diffraction was used to analyze microstructure and LPOs of 37 quartzofeldspathic gneiss samples that enclose meter-scale mafic blocks preserving original eclogite-facies assemblages. During exhumation of the ultrahigh-pressure (UHP) terrane, gneisses were retrogressed in the amphibolite …


Dendrochronological Analysis Of Four Sommerset Structures, 2013 The College of Wooster

Dendrochronological Analysis Of Four Sommerset Structures

Historic Structures

Dating historical structures in Somerset, Ohio 2013. The Historical Structures collection consists of reports that are the result of dendochronological analysis of timbers from structures in Pennsylvania and Ohio. Contributors: Stewart, Alexander; Wiesenberg, Nicholas; Wiles, Greg


Investigations Into The Regional And Local Timescale Variations Of Subglacial Drainage Networks, Justin Hiester 2013 Portland State University

Investigations Into The Regional And Local Timescale Variations Of Subglacial Drainage Networks, Justin Hiester

Dissertations and Theses

Subglacial water plays an important role in the regulation of an ice sheet's mass balance. It may be the dominant control on the velocities of ice streams and outlet glaciers on scales of months to millennia. Recent satellite observations of ice surface elevation changes have given researchers new insights into how subglacial water is stored and transported. Localized uplift and settling of the ice surface implies that lakes exist beneath the ice sheet that are being filled and drained on relatively short time scales. %At the base of an ice sheet water can be transported through a variety of drainage …


Oil-Source Rock Correlation In The Late Paleozoic, Denver Basin, Nebraska: The Search For A Negative Δ¹³C Anomaly In Pennsylvanian–Permian Cyclothems, John P. Still 2013 University of Nebraska-Lincoln

Oil-Source Rock Correlation In The Late Paleozoic, Denver Basin, Nebraska: The Search For A Negative Δ¹³C Anomaly In Pennsylvanian–Permian Cyclothems, John P. Still

Department of Earth and Atmospheric Sciences: Dissertations, Theses, and Student Research

Late Paleozoic sedimentation in the Denver basin occurred in two environmentally distinct depocenters. The northern-most Alliance Basin has been interpreted to have a restricted character: anhydrite-bearing mudstones are present in cyclothems comprising wackestone, packstone and mudstone. The source of petroleum produced from these intervals is considered to be organic-rich units within these cyclothems. Oil recovered from late Paleozoic reservoirs has δ13C values that range from -30.8‰ to -28.8‰: values that are lower than those reported previously for prospective source rocks from this interval. Cores from seven wells that penetrate upper Pennsylvanian to lower Permian rocks have been chosen for analysis. …


Lower San Luis Obispo Creek Stewardship Plan, Raven Lukehart, Daniel Bohlman 2013 California Polytechnic State University, San Luis Obispo

Lower San Luis Obispo Creek Stewardship Plan, Raven Lukehart, Daniel Bohlman

Natural Resources Management and Environmental Sciences

No abstract provided.


Late-Quaternary Channel Migration In Red Rock Canyon State Park, California; Implications For Regional Tectonics, Kirk Forrest Townsend 2013 California Polytechnic State University, San Luis Obispo

Late-Quaternary Channel Migration In Red Rock Canyon State Park, California; Implications For Regional Tectonics, Kirk Forrest Townsend

Natural Resources Management and Environmental Sciences

The Iron Canyon Valley, located at the southern end of the eastern Sierra Nevada at the boundary between the Mojave and Basin and Range tectonic provinces, exhibits clear evidence, over graded timescales, of development through monoclinal shifting, which is the tendency of streams flowing parallel to strike over sedimentary rocks to shift down-dip. Although the character of the valley and bedrock dip indicates development through monoclinal shifting, the current stream network is located up-dip on the east side of the valley. Mapping the surficial geology of the valley revealed the presence of dissected alluvial surfaces approximately 85 meters above modern …


Were All Devonian Seeds Cupulate? A Reinvestigation Of Pseudosporogonites Hallei, Xenotheca Bertrandii, And Aglosperma Spp., Cyrille Prestianni, Jason Hilton, Walter L. Cressler 2013 West Chester University

Were All Devonian Seeds Cupulate? A Reinvestigation Of Pseudosporogonites Hallei, Xenotheca Bertrandii, And Aglosperma Spp., Cyrille Prestianni, Jason Hilton, Walter L. Cressler

Earth & Space Sciences Faculty Publications

No abstract provided.


Examining Antarctica From A Geodynamic Perspective: Backstripping, Ice Thickness, Tectonics And Erosion, Travis Gary Hayden 2013 Western Michigan University

Examining Antarctica From A Geodynamic Perspective: Backstripping, Ice Thickness, Tectonics And Erosion, Travis Gary Hayden

Dissertations

I have applied the principles of basin analysis and geodynamics to several cores recovered from on or near the Antarctic continent to answer 2 independent questions about the tectonic evolution of Antarctica; as well as estimate the thickness of the Antarctic Ice Sheet at the Last Glacial Maximum.

I developed, and applied a modification of the backstripping modeling technique to compensate for the loading and erosion of glacial ice at the AND-1B site by combining a backstripping driven inverse model, with a driven ice-load model. This modification allowed me to identify and constrain the timing of major pulses of subsidence …


Evidence Of Songbird Intoxication From Rozol Application At A Black-Tailed Prairie Dog Colony, Nimish B. Vyas, Craig S. Hulse, Carol U. Meteyer, Clifford P. Rice 2013 Patuxent Wildlife Research Center

Evidence Of Songbird Intoxication From Rozol Application At A Black-Tailed Prairie Dog Colony, Nimish B. Vyas, Craig S. Hulse, Carol U. Meteyer, Clifford P. Rice

United States Geological Survey: Staff Publications

Concerns about avian poisonings from anticoagulant rodenticides have traditionally focused on secondary poisoning of raptors exposed by feeding on contaminated mammalian prey. However, ground foraging songbirds can be directly poisoned from operational applications of the anticoagulant rodenticide RozolH (0.005% chlorophacinone, active ingredient) applied as a grain bait, at black-tailed prairie dog Cynomys ludovicianus colonies. A dead western meadowlark Sturnella neglecta recovered from the study prairie dog colony displayed hemorrhaging in brain and pectoral muscle tissue, and it contained chlorophacinone residue concentrations of 0.59 and 0.49 mg/g (wet weight) in the liver and intestinal contents, respectively. Chlorophacinone residues from two Rozol-colored …


The Geology Of The South Antelope Pass Area Of The Southern Peloncillo Mountains, Hidalgo County, New Mexico, John A. Yellich 2013 Western Michigan University

The Geology Of The South Antelope Pass Area Of The Southern Peloncillo Mountains, Hidalgo County, New Mexico, John A. Yellich

Masters Theses

Volcanic activity during the middle and late Tertiary has been recorded in the mountain ranges of the southwestern United States and northern Mexico and the two provinces of prominent volcanic activity, the Sierra Madre Occidental and the Mogollon Plateau, dominantly rhyolitic in composition, are connected by the Peloncillo Range. The predominant rock chemistry of the south Antelope Pass area is “rhyolitic”; however, lava rock types dominate over welded tuff rock types of the two provinces. There is a limited pre-Tertiary rock record of limestones and sandstones in the northeastern part of the study area. The rest of the study area …


Exploring Connections Between A Very Large Volume Ignimbrite And An Intracaldera Pluton: Intrusions Related To The Oligocene Wah Wah Springs Tuff, Western Us, Chloe Noelle Skidmore 2013 Brigham Young University - Provo

Exploring Connections Between A Very Large Volume Ignimbrite And An Intracaldera Pluton: Intrusions Related To The Oligocene Wah Wah Springs Tuff, Western Us, Chloe Noelle Skidmore

Theses and Dissertations

The Wah Wah Springs Tuff and the Wah Wah Springs Intrusive Granodiorite Porphyry(Wah Wah Springs Intrusion) both originated from the Indian Peak caldera complex, which wasa major focus of explosive silicic activity in the middle Cenozoic Great Basin ignimbrite flareup. This caldera formed 30.0 Ma when an estimated 5,900 km3 of crystal-rich dacitic magma erupted to create the Wah Wah Springs Tuff. The Wah Wah Springs Intrusion later intruded the tuff, causing resurgence of the caldera. Field, modal, and geochemical evidence suggest the tuff and intrusion are cogenetic. The mineral assemblages of the two rocks are similar: both include similar …


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