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Transitional Facies And Sequence Stratigraphic Complexity Of Shallow-Marine Star Point Formation To Coastal-Plain Blackhawk Formation Along Depositional-Strike, Wasatch Plateau, Utah, Andrew M. Ranson 2012 University of New Orleans

Transitional Facies And Sequence Stratigraphic Complexity Of Shallow-Marine Star Point Formation To Coastal-Plain Blackhawk Formation Along Depositional-Strike, Wasatch Plateau, Utah, Andrew M. Ranson

University of New Orleans Theses and Dissertations

Facies and stratigraphic architecture right at the transition from marine to non-marine environments is poorly documented. In the Cretaceous outcrops of Utah, Star Point and Blackhawk Formations are well studied. The nature of spatio-temporal transition of these two Formations, in the deposition-strike orientation, remains undocumented. This study characterizes facies and stratigraphic complexity at the transition of the two Formations that crop out in depositional-strike orientation in the Wasatch Plateau. Data from outcrop including photomosiacs and measured sections demonstrate this complexity at a range of scales. The Star Point constitutes a shoreface environment. The Blackhawk constitutes a coastal-fluvial environment.

In the …


Metallogenic Setting Of High-Grade Iron Ores, Mary River District, North Baffin Island, Nunavut, Meghan E. MacLeod 2012 The University of Western Ontario

Metallogenic Setting Of High-Grade Iron Ores, Mary River District, North Baffin Island, Nunavut, Meghan E. Macleod

Electronic Thesis and Dissertation Repository

Supracrustals of the 2.76-2.71 Ga Mary River Group form the northeastern segment of the Committee Bay Belt. Field mapping has determined that this succession is preserved in structural keels marginal to high-grade gneiss domes and is characterized by lower metasedimentary rocks and an upper BIF-komatiite-quartzite succession. Algoma-type BIF sited at the dome/keel boundary is host to bodies of high-grade iron ore, the largest being Deposit 1 which has an estimated reserve of 500 mt averaging 64 wt % Fe.

Field mapping, petrography, and EMPA indicates 3 main stages of ore formation. Stage 1 was characterized by the formation of the …


Monitoring Glacier Surface Seismicity In Time And Space Using Rayleigh Waves, T. D. Mikesell, K. van Wijk, M. M. Haney, J. H, Bradford, H. P. Marshall, Joel T. Harper 2012 Universite de Nice - Sophia Antipolis

Monitoring Glacier Surface Seismicity In Time And Space Using Rayleigh Waves, T. D. Mikesell, K. Van Wijk, M. M. Haney, J. H, Bradford, H. P. Marshall, Joel T. Harper

Geosciences Faculty Publications

Sliding glaciers and brittle ice failure generate seismic body and surface wave energy characteristic to the source mechanism. Here we analyze continuous seismic recordings from an array of nine short-period passive seismometers located on Bench Glacier, Alaska (USA) (61.033N, 145.687W). We focus on the arrival-time and amplitude information of the dominant Rayleigh wave phase. Over a 46-hour period we detect thousands of events using a cross-correlation based event identification method. Travel-time inversion of a subset of events (7% of the total) defines an active crevasse, propagating more than 200 meters in three hours. From the Rayleigh wave amplitudes, we estimate …


Atmospheric Circulation Change In The Central Himalayas Indicated By A High-Resolution Ice Core Deuterium Excess Record, Hongxi Pang, Shugui Hou, Susan Kaspari, Paul Mayewski, Douglas Introne, Valérie Masson-Delmotte, Jean Jouzel, Zhenchao Li, Yuanqing He, Sungmin Hong, Dahe Qin 2012 Nanjing University

Atmospheric Circulation Change In The Central Himalayas Indicated By A High-Resolution Ice Core Deuterium Excess Record, Hongxi Pang, Shugui Hou, Susan Kaspari, Paul Mayewski, Douglas Introne, Valérie Masson-Delmotte, Jean Jouzel, Zhenchao Li, Yuanqing He, Sungmin Hong, Dahe Qin

All Faculty Scholarship for the College of the Sciences

Continuous measurements of both δD and δ18O were performed along a 108.8 m ice core recovered from the East Rongbuk Glacier on the northeast saddle of Mt. Qomolangma (Everest) (28.03° N, 86.96° E, 6518 m above sea level) in September 2002. They provide the first high-resolution historical record of deuterium excess (d) in the central Himalayas. In this paper, we focus on d variability from 1951 to 2001 and its relationship with large scale atmospheric circulation. The d record exhibits significant seasonal variations, with low values in summer and high values in winter, reflecting the atmospheric circulation shift between winter …


Diatoms As Recorders Of Sea Ice In The Bering And Chukchi Seas: Proxy Development And Application, Beth A. Caisse 2012 University of Massachusetts Amherst

Diatoms As Recorders Of Sea Ice In The Bering And Chukchi Seas: Proxy Development And Application, Beth A. Caisse

Open Access Dissertations

The recent, rapid decline in Arctic summer sea ice extent has prompted questions as to the rates and magnitude of previous sea ice decline and the affect of this physical change on icerelated ecosystems. However, satellite data of sea ice only extends back to 1978, and mapped observations of sea ice prior to the 1970s are sparse at best. Inventories of boreal ecosystems are likewise hampered by a paucity of investigations spanning more than the past few decades. Paleoclimate records of sea ice and related primary productivity are thus integral to understanding how sea ice responds to a changing climate. …


High-Resolution Correlation Of The Upper Cretaceous Stratigraphy Between The Book Cliffs And The Western Henry Mountains Syncline, Utah, U.S.A., Drew L. Seymour 2012 University of Nebraska

High-Resolution Correlation Of The Upper Cretaceous Stratigraphy Between The Book Cliffs And The Western Henry Mountains Syncline, Utah, U.S.A., Drew L. Seymour

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

This study presents high-resolution correlations of the Upper Cretaceous stratigraphy between the Book Cliffs and the western Henry Mountains Syncline in Utah. The objective of this study is to understand changes in patterns of regional sediment dispersal during the Late Cretaceous on the western margin of the Cretaceous Western Interior Seaway. The intensely studied Book Cliffs consist of formations deposited in terrestrial, marginal-marine, and open-marine environments. A composite section was logged at Coal Canyon near Green River, UT. The western Henry Mountains Syncline is located in south-central Utah ~135 km S-SW of Coal Canyon. A composite section was logged at …


Road Dust Lead (Pb) In Two Neighborhoods Of Urban Atlanta, (Ga, Usa), Daniel Deocampo Ph.D, Phillip Jack Reed, Alexander P. Kalenuik 2012 Georgia State University

Road Dust Lead (Pb) In Two Neighborhoods Of Urban Atlanta, (Ga, Usa), Daniel Deocampo Ph.D, Phillip Jack Reed, Alexander P. Kalenuik

Geosciences Faculty Publications

Road dust continues to be a major potential reservoir of Pb in the urban environment, and an important potential component of child Pb exposure. This study presents ICP-AES analyses of metals in 72 samples of road dust (<250 μm) collected in the urban core of Atlanta, Georgia. In the Downtown area, median Pb concentrations are ~63 mg/kg Pb, with high values of 278 mg/kg. For comparison, median Pb values in a nearby residential neighborhood (also in the urban core) were ~93 mg/kg, with a high of 972 mg/kg. Geospatial variability is high, with significant variation observed over tens to hundreds of meters. Spearman Rank Correlation tests suggest that Pb and other metals (Cu, Ni, V, Zn) are associated with iron and manganese oxide phases in the residential area, as reported in other cities. However, Pb in the Downtown area is not correlated with the others, suggesting a difference in source or transport history. Given these complexities and the expected differences between road dust and soil Pb, future efforts to assess exposure risk should therefore be based on spatially distributed sampling at very high spatial resolution.


Characterizing Phyllosilicate Distribution, Abundance, And Origin On Mars, Christina Elizabeth Viviano 2012 University of Tennessee, Knoxville

Characterizing Phyllosilicate Distribution, Abundance, And Origin On Mars, Christina Elizabeth Viviano

Doctoral Dissertations

Secondary phyllosilicates are hydrated minerals formed in the presence of liquid water. On Earth, their formation is often indicative of a neutral, water-rich environment, capable of supporting and preserving organic matter. Different phyllosilicate species may be produced in different pH levels and water-to-rock ratios. The identification of mineralogically diverse phyllosilicates in small, localized exposures on Mars provides a complex record of their formation processes. While discrete outcrops of phyllosilicates have been previously identified in high-resolution visible/near-infrared images of Mars, regional coverage of these phyllosilicate-rich areas at better resolution is limited. Furthermore, spectra of minerals in this wavelength range do not …


From The Mantle To The Moon: Studies Of Kimberlitic Ilmenites, Meteorite Fusion-Crusts, And The Moscoviense Basin On The Moon, Kevin Glenn Thaisen 2012 University of Tennessee, Knoxville

From The Mantle To The Moon: Studies Of Kimberlitic Ilmenites, Meteorite Fusion-Crusts, And The Moscoviense Basin On The Moon, Kevin Glenn Thaisen

Doctoral Dissertations

I have explored a variety of geologic problems in the course of the chapters contained within this dissertation. These include a study relating to the fusion crusts on meteorites, an impact basin of the Moon, and Siberian kimberlitic ilmenites. The first chapter explores two assumptions commonly employed in meteorite analysis; that fusion crust compositions represent the bulk-rock chemistry of the entire meteorite and that the vesicles within the fusion crust result from the release of implanted solar-wind volatiles. Neither of these assumptions was found to hold true in that study. The second chapter explores the unusual nature of the Moscoviense …


Chemical Weathering Of The Mafic Minerals Serpentine And Olivine In Natural Environments, Julie Lynn Baumeister 2012 University of Nevada, Las Vegas

Chemical Weathering Of The Mafic Minerals Serpentine And Olivine In Natural Environments, Julie Lynn Baumeister

UNLV Theses, Dissertations, Professional Papers, and Capstones

Chemical weathering is a critical process that plays a key role in controlling the chemistry of natural waters, the cycling of atmospheric carbon dioxide, and the formation of soil. The weathering of silicate minerals is important because the Earth's crust is composed of approximately 92 weight percent silicate minerals. Despite an extensive literature on mineral dissolution and kinetics, relatively few studies have examined weathering of the mafic minerals serpentine and olivine, especially in a natural environment. The first chapter of this thesis provides an introduction to the minerals serpentine and olivine. The second chapter of this thesis examines the important …


A Mineralogical Textural And Chemical Characterization Of A Hypothesized Kimberlite At White Mountain, Sunlight Basin, Wyoming, Stuart Kenderes 2012 Western Kentucky University

A Mineralogical Textural And Chemical Characterization Of A Hypothesized Kimberlite At White Mountain, Sunlight Basin, Wyoming, Stuart Kenderes

Mahurin Honors College Capstone Experience/Thesis Projects

Geologists have examined the causes and mechanisms responsible for the Heart Mountain detachment for over a century with much debate and discussion. White Mountain is a part of the upper plate, which was emplaced during the detachment event. Within White Mountain, there exist several andesitic dikes and carbonate ultra-cataclasite injectites, which were integral in the emplacement of the Heart Mountain detachment. This research involves the characterization and identification of an enigmatic vertical outcropping of brecciated rock located on White Mountain, Sunlight Basin, Wyoming, which was originally interpreted as a kimberlite. Samples were collected for geochemical and textural comparison, and cut …


Remote Sensing Analysis Of Hydrological Functionality Of Playa Wetlands Using Landsat Tm/Etm+ Data, Benjamin F. Grover 2012 Fort Hays State University

Remote Sensing Analysis Of Hydrological Functionality Of Playa Wetlands Using Landsat Tm/Etm+ Data, Benjamin F. Grover

Master's Theses

A playa wetland’s ability to retain moisture and water has the greatest influence on the ecological and hydrological functionality of the playa. In this project, Landsat TM/ETM+ satellite imagery was analyzed to determine whether it could be used to detect hydrological functionality of playa wetlands based on their temporal ability to retain soil moisture and water. The project consisted of a ground truth study in which soil moisture, water content, and vegetation data was gathered from the area and related to the satellite imagery pixel values. With this data, a maximum likelihood classifier was created using the mean pixel values …


Using Landsat Thematic Mapper Satellite Imagery: Assessing And Mapping Trophic State In Cheney Reservoir, Kansas, Dingnan Lu 2012 Fort Hays State University

Using Landsat Thematic Mapper Satellite Imagery: Assessing And Mapping Trophic State In Cheney Reservoir, Kansas, Dingnan Lu

Master's Theses

Eutrophication is a major inland water problem that is researched by many environmentalists and hydrologists. A eutrophic inland water body can cause many negative water problems, such as taste and odor, biotoxin, and low dissolved oxygen. Many previous studies were effective based on using remote sensing to evaluate water body trophic state. In this study, the Cheney Reservoir is selected as an object to test the performance of using remote sensing, specifically the Landsat Thematic Mapper sensor, to evaluate the trophic state of a reservoir. Based on Landsat TM imagery, the chlorophyll a concentration is estimated to be used to …


Structure And Rheology Of The Sandhill Corner Shear Zone, Norumbega Fault System, Maine: A Study Of A Fault From The Base Of The Seismogenic Zone, Nancy Ann Price 2012 The University of Maine

Structure And Rheology Of The Sandhill Corner Shear Zone, Norumbega Fault System, Maine: A Study Of A Fault From The Base Of The Seismogenic Zone, Nancy Ann Price

Electronic Theses and Dissertations

Determining the structure and rheology of a seismogenic fault at frictional-to-viscous transition (FVT) depths is vital for understanding its strength and behavior. Few studies describe a fault from within this depth level, so the architecture of a shear zone at these depths as well as the effect of transient coseismic and postseismic deformation on the rheology of the shear zone is poorly-understood. The Sandhill Corner strand of the Paleozoic Norumbega fault system of Maine is the one of the few known examples of a subvertical, strike-slip fault exhumed from FVT depths. Using a suite of samples collected from the Sandhill …


Hillslope Asymmetry Maps Reveal Widespread, Multi-Scale Organization, Michael John Poulos 2012 Boise State University

Hillslope Asymmetry Maps Reveal Widespread, Multi-Scale Organization, Michael John Poulos

Boise State University Theses and Dissertations

Hillslope asymmetry is the condition in which oppositely-facing hillslopes within an area have differing average slope angles, and indicates aspect-related variability in hillslope evolution. As such, the presence, orientation, and magnitude of asymmetry may be a useful diagnostic for understanding process dominance. We present a new method for quantifying and mapping the spatial distribution of hillslope asymmetry across large areas. Resulting maps for the American Cordillera of the Western Hemisphere and the western United States reveal that hillslope asymmetry is widespread, with distinct trends at continental to drainage scales. Spatial patterns of asymmetry correlate with latitude along the American Cordillera, …


A 14,000-Year Record Of Wildfire And Alluvial Fan Deposition Reveals Relationships Among Fire, Climate, Vegetation, And Sediment Yields In The Middle Fork Salmon River, Idaho, Kerry Elizabeth Riley 2012 Boise State University

A 14,000-Year Record Of Wildfire And Alluvial Fan Deposition Reveals Relationships Among Fire, Climate, Vegetation, And Sediment Yields In The Middle Fork Salmon River, Idaho, Kerry Elizabeth Riley

Boise State University Theses and Dissertations

Changes in climate influence vegetation distributions and the frequency and severity of fire and post-fire erosion. While the frequency of large fires has increased on all vegetated continents over the last decade, it remains unclear whether recent large fires are extraordinary over millennial timescales. In the Middle Fork Salmon River of central Idaho, over 40% of the watershed has burned in the last 30 years and the subsequent increase in erosion from severely burned hillslopes has produced many large fire-related debris flows. Fires have burned throughout the steep topographic gradient of the watershed that encompasses high elevation sub-alpine and mixed …


Geoarchaeology Of The Orontes River Floodplain Surrounding Tell Qarqur, Syria, Anna Flora Wieser 2012 University of Arkansas, Fayetteville

Geoarchaeology Of The Orontes River Floodplain Surrounding Tell Qarqur, Syria, Anna Flora Wieser

Graduate Theses and Dissertations

This project combines geoarchaeological soil description and GIS analysis of archaeological site distribution to investigate the history of marsh formation in the northern Ghab Basin, located within the Orontes River Valley of western Syria. Tell Qarqur, the archaeological site around which this project is focused, has a continuous occupational sequence throughout the Holocene. Annual inundation of the site by seasonal marshlands suggests that the marsh was either smaller or non-existent in the past, but its history remains unknown. The objectives of this investigation are to interpret the nature of depositional environments, particularly fluvial action, in the vicinity of Tell Qarqur, …


An Evaluation Of The History Of Aqueous Activity On Mars Through A Survey Of Select Hypothesized Martian Deltas And Paleolakes Via The Analysis Of Mineralogy, Morphology, And Thermophysical Properties, Andrea C.G. Hughes 2012 University of Tennessee, Knoxville

An Evaluation Of The History Of Aqueous Activity On Mars Through A Survey Of Select Hypothesized Martian Deltas And Paleolakes Via The Analysis Of Mineralogy, Morphology, And Thermophysical Properties, Andrea C.G. Hughes

Masters Theses

Aqueous deposits are an essential key to understanding the geologic/climatic history of water on Mars. The Compact Reconnaissance Imaging Spectrometer for Mars (CRISM), High Resolution Imaging Science Experiment (HiRISE), and Thermal Emission Imaging System (THEMIS) have enabled studies of Martian fan deposits in unprecedented detail, including the identification of hydrated minerals (such as phyllosilicates, carbonates, and sulfates) and morphologies consistent with formation in an aqueous environment associated with Martian sedimentary deposits. In this study, twenty-six previously identified fan-shaped deposits (hypothesized as possible deltas) have been examined for hydrated minerals in the beds and distal regions of the deposits. Six deposits …


Data Integration And Reservoir Characterization Of The Pennsylvanian Bartlesville Sandstone, Caroline Vance O'Keefe 2012 University of Arkansas, Fayetteville

Data Integration And Reservoir Characterization Of The Pennsylvanian Bartlesville Sandstone, Caroline Vance O'Keefe

Graduate Theses and Dissertations

The Glenn Pool Oil Field of Northeastern Oklahoma was established as the first major oil discovery of the fledgling state of Oklahoma. Fully developed by 1912, the field is now nearing depletion even under secondary and tertiary recovery efforts after production for approximately 100 years. Large amounts of residual oil estimated to still be in place have motivated exploration into other recovery methods, including polymer flooding and horizontal drilling. Success of these programs is dependent upon accurate characterization of the reservoir. Because most of the drilling occurred many decades ago, much of the data associated with this field predates electric …


Impacts Of Hard Stabilization On The Shore Of Yellowstone Lake, Yellowstone National Park, Wyoming, Usa, John Chandler Dennis 2012 University of Arkansas, Fayetteville

Impacts Of Hard Stabilization On The Shore Of Yellowstone Lake, Yellowstone National Park, Wyoming, Usa, John Chandler Dennis

Graduate Theses and Dissertations

Discussions related to the adverse impacts associated with shore armor (i.e. seawalls and riprap) are a common topic within the coastal community. While many agree that the installation of these structures alters the shores geomorphic response, there is disagreement in the type and degree of response. Furthermore, studies that have delved into this topic have been conducted in numerous settings but have been confounded by a lack of data regarding shore morphologies prior to installation of these structures. At Yellowstone National Park, there is an opportunity to assess the impacts of shore armor quantitatively because the National Park Service requires …


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