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Spatial Analysis Of Substantiated Child Maltreatment In Metro Atlanta, Georgia, Yueqin Zhou

Geosciences Theses

Identifying high-risk areas for child maltreatment to ultimately aid public health agencies for interventions is necessary for protecting children at high risk. Rates of substantiated neglect and physical/emotional abuse in 2000-2002 are computed for the census tracts in the urban area of five counties in Metro Atlanta, Georgia, and analyzed using spatial regression to determine their relationships with twelve risk variables computed from the Vital Records births and the 2000 Census data. After accounting for multicollinearity among risk variables and spatial autocorrelation among observations for neighboring locations, it is found that high percentages of (1) births to non-married mothers, (2) …

Thermodynamics Of Metals Adsorption Onto Uranium Dioxide, Koi Ling Lim

Masters Theses

Wastes and pollution containing uranium are released to the environment through mining, ore processing, industrial manufacture of nuclear fuel and weapons materials, and the disposal of spent nuclear fuel. There are a wide variety of processes that can affect UO₂ stability. This research focuses on the surface reactivity of UO₂ in reducing aqueous solutions, with an emphasis on assessment of the pH-dependent surface charge, reactive surface area, and the adsorption of dissolved lead (Pb), cadmium (Cd), lanthanum (La) onto UO₂ particles. A surface complexation model was used to explain the adsorption and titration phenomena of UO_{2 …}

Origin And Tectonic Evolution Of The Southern Appalachian Neoacadin Crystalline Core: Evidence From The Geology Of The Gilreath 7.5-Minute Quadrangle, North Carolina, Crystal Gayle Wilson

Masters Theses

Detailed geologic mapping of the Gilreath 7.5-minute quadrangle recognizes the northernmost continuation of the Brindle Creek fault, a terrane boundary that separates Neoproterozic-Ordovician metasedimentary and metavolcanic rocks of the western Tugaloo terrane (western Inner Piedmont) from Silurian-Devonian metasedimentary rocks and Devonian-Mississippian anatectic granitoids of the Cat Square terrane (eastern Inner Piedmont). The Brindle Creek fault is folded in the study area and exposes the Ordovician Brooks Crossroads Granite in a reentrant. Low high-field strength element concentrations and a flatter rare earth element patterns typical of western Inner Piedmont granitoids, support a footwall setting for the Brooks Crossroads Granite.

New geochemical …

Petrogenesis Of Apollo 15 Olivine-Normative And Quartz-Normative Mare Basalts, Darren W. Schnare

Masters Theses

New data are presented for four Apollo 15 low-Ti mare basalts, two from the olivine-normative suite (15106, and 15555) and two from the quartz-normative suite (15475, and 15499). Previous studies have examined the relationships between these groups on the basis of whole-rock chemistry, many with analyses that may have been of insufficient sample-size, or of limited range of elements analyzed. To determine a relationship between these basalts, these samples have been analyzed for their mineral major-element and trace-element compositions by electron-microprobe and laser-ablation inductively-coupled-plasma mass-spectrometry, respectively.

The trace-element compositions of the main silicate phases, olivine, pyroxene, and plagioclase, are consistent …

Investigation Of Oxy-Anion Legand Adsorption Onto Surfaces Of Iron Oxide And Bacteria In Groundwater Aquifers, Haile Mengistu

Dissertations

We have measured adsorption of dissolved phosphate onto synthetic hydrous ferric oxide (HFO), dissolved arsenate and chromate onto the cell membrane of a bacterium species, S. putrefaciens as a function of pH, ionic strength, and relative concentrations of the respective oxy-ligands. Our experimental data were used to constrain optimal values for surface complexation reactions involving dissolved oxi-ligands (phosphate, and chromate) and the HFO surface and the cell membrane of S. putrefaciens respectively according to the diffuse layer model.

Our results provide a more accurate fit to experimental measurements over a broader range of pH (3 - 12), ionic strength and …

Petrogenesis Of Eocene-Oligocene Magmatism Of The Sulphur Springs Range, Central Nevada: The Role Of Magma Mixing, Elizabeth Balls Ryskamp

Theses and Dissertations

Widespread base- and precious-metal anomalies, altered porphyry intrusions and oxidized veins occur in a portion of the Sulphur Springs Range, Nevada (adjacent to the Au-producing Carlin Trend). Some of the Eocene-Oligocene intrusions and cogenetic volcanic rocks in the range exhibit evidence of magma mixing and invite comparisons with other mineralized, Eocene mixed magma systems like the Bingham porphyry Cu deposit 300 km farther to the east. The Sulphur Springs igneous suite ranges compositionally through rhyolite, dacite, andesite and basaltic andesite but is less alkaline than the Bingham volcanic suite. However, the alkali content of the Sulphur Springs suite is similar …

Garnetites Of The Cardigan Pluton - Evidence For Restite And Implications For Source Rock Compositions., Teresa K. Pett

Theses and Dissertations

The Cardigan pluton, located in the southern half of New Hampshire, is a strongly peraluminous, S-type granite which is granodioritic in composition. It is inferred to have been emplaced rapidly, thrust up along west-verging nappes during the Acadian orogeny. Distinctive pods, consisting of 50 to 70 percent modal garnet, are found throughout the pluton in assemblages of garnet + sillimanite + biotite + plagioclase + quartz. These garnetite rocks present an intriguing case for restite. Textural features of the garnetite rocks, such as fibrolitic sillimanite mats and flat, unzoned major and trace-element garnet grain profiles, provide evidence for biotite dehydration …

Quaternary Deposits Near The San Emigdio Mountains, California: Evidence For A Paleolandscape?, Paul G. Lavelle

Earth and Soil Sciences

Discontinuous low-relief surfaces are scattered throughout relatively high topography within the San Emigdio Mountains, California. These surfaces are considered anomalous, as they are preserved in a dissected, mountainous region that is affected by ongoing orogeny. Previous research has suggested that the low-relief surfaces may represent a once-contiguous alluvial surface. This project utilizes field mapping and sedimentological analysis to determine if the surfaces represent a paleo landscape. What is apparent from field work is the presence of two morphologically distinct lithologic units that most likely represent surficial geologic components of the same relict landscape.

Detection Of A Landslide Glide Plane Using Seismic Reflection Methods: Investigation At Little Valley Landslide In Draper, Utah, Brady E. Tingey

Theses and Dissertations

An integration of geological and geophysical techniques has been used to characterize the internal structure of the Little Valley Landslide in Draper, Utah, USA. The Little Valley Landslide is a pre-historic landslide as old as 13ka B.P. It is found to consist of chaotic and disturbed weathered volcanic units derived from Tertiary age volcanics that comprise a great portion of the Wasatch Range. Geotechnical investigations that were integrated with the geophysical results included excavation of trenches and drilling of boreholes. Geophysical methods, in particular high-resolution seismic data, were used to provide a framework for interpreting the geotechnical observations. High-resolution seismic …

Potential Subsurface Structures And Hydrocarbon Reservoirs In The Southern Appalachian Basin Beneath The Cumberland Plateau And Eastern Highland Rim, Tennessee, Kentucky, And Southwestern Virginia, Jonathan Charles Evenick

Doctoral Dissertations

Oil and gas exploration in the southern Appalachian basin is typically concentrated around areas with historically proven reserves and very limited prospecting is conducted elsewhere in the region. To remove possible correlation problems and promote regional prospecting a standardized picking methodology was established in geophysical logs for the Middle Ordovician carbonate lithofacies (Nashville-Stones River Groups). This methodology was then used to correlate the units across Cumberland Plateau of Tennessee, Kentucky, and Virginia, from the Nashville-Jessamine domes to the Clinchport-Whiteoak Mountain thrust in the Valley and Ridge. The same lithofacies may extend in Ohio, Pennsylvania, and New York, suggesting a standardized …

Solute Transport And U(Vi) Reactivity In Natural Heterogeneous Sediments, Melanie A. Mays

Doctoral Dissertations

The primary goal of this research was to determine the relationship between sedimentary geology and solute transport parameters. The overall hypothesis was that the transport of reactive and nonreactive solutes can be predicted using observable sedimentary depositional characteristics. The objective was to test this hypothesis by performing a variety of quantitative transport experiments in intact layered sediment samples. In this study, I used natural materials to explore 1) how mineralogical composition influenced the fate and transport of uranium(VI), 2) the relationship between heterogeneous sedimentary layering and preference for direction of flow, and 3) the mechanisms of solute transport in a …

Biomarker And Stable Isotope Characterization Of Coastal Pond Organic Matter, Mcmurdo Dry Valleys, Antarctica, Melissa Margaret Hage

Masters Theses

Small coastal ponds containing photosynthetic microbial mat communities represent a potentially significant source of labile organic carbon within the McMurdoDryValleys, Antarctica. To distinguish coastal pond derived organic matter (CPDOM) from other sources of organic matter in the dry valleys, I investigated bulk organic carbon and nitrogen isotopic signatures and phospholipid fatty acid (PLFA) profiles of benthic microbial mats located at two sites, HjorthHillCoastand GarwoodValley. The average δ¹³C values at Hjorth Hill Coast and Garwood Valley are -10.91 ‰ and -10.19 ‰, respectively. The average δ¹⁵N values are 3.73 ‰ and -1.25 ‰, respectively. Microbial mats from …

Geochemical Characterization Of Coastal Pond And Adjacent Soil Organic Matter From Two Distinct Field Areas Of The Mcmurdo Dry Valleys, Antarctica, Meg E. Howard

Masters Theses

The McMurdo Dry Valleys (MDV), Antarctica contains some of the few ice-free oases on the continent, and is one of the coldest, driest places on earth. Despite the harsh conditions, the MDV supports an abundance of biological communities within soil and aquatic systems. Bioavailable carbon is present in these systems in the form of ancient and modern sources. An additional source of bioavailable carbon that has largely been ignored may be represented by desiccated and disseminated microbial mats (coastal pond organic matter, or CP-OM) originating in ephemeral coastal meltwater ponds of the MDV. The goal of this study is to …

Mechanisms For Increasing Respiratory Capacity Through Ontogeny In The Blastoid Genus Pentremites, Troy A. Dexter

Masters Theses

This study was conducted to determine how the hydrospires in blastoids (the respiratory channels through which blastoids respire) change in shape and capacity during ontogeny. As the volume of a blastoid increases ontogenetically, the respiratory capacity of the hydrospires must increase to match the additional respiratory requirements. Ontogenetically, volume increases at a cubic rate, therefore the surface area of the respiratory structures should increase at a similar rate. Using transverse cross sections of the theca through an ontogenetic series in two species of the blastoid Pentremites, the surface area and volume of the hydrospires was quantified. The data demonstrated …

A Quantitative Study Of Scaling Properties Of Fracture Networks, Ankur Roy

Masters Theses

Fracture networks and their scaling properties are important from both an academic and practical perspective since they play a significant role in many areas ranging from crustal fluid flow to studies of earthquakes. Over the years, researchers have employed a wide variety of techniques to quantify the complexities of fractured media. These range from deterministic, process-based approaches employing the laws of physics, to ones involving the applications of geostatistics and more recently, fractal geometry. Fractals are irregular entities that show self-similarity over a wide range of scales and can be quantified by the fractal dimension, D. It is important …

Pyrogenic Polycyclic Aromatic Hydrocarbons From Carboniferous, Triassic, And Modern Chars: Potential Relations To Paleoatmospheric Oxygen Content, Patrick Jerome Schuneman

Masters Theses

Atmospheric oxygen concentrations may have dramatically fluctuated throughout the Phanerozoic. Because oxygen is critical to fire, major oxygen fluctuations may have significantly affected biomass burning occurrences, suggesting that wildfires would have been more prevalent at times of elevated oxygen. Fossil charcoal abundances in the geologic record qualitatively reflect this relationship. Land plants evolved by the late Silurian, and the earliest true forests evolved by the mid-Devonian, while oxygen levels were still low. Fuel accumulations and oxygen content probably did not reach sufficient levels to sustain burning until the late-Devonian. There are only one or two isolated examples of fossil charcoal …

Evidence Of An Active Enso And Pdq During The Mid-Holocene From A Costa Rican Speleothem, April D. Azouz

UNLV Theses, Dissertations, Professional Papers, and Capstones

Although the El Nino/Southern Oscillation (ENSO) is the most important source of inter-annual climate variability in the tropics, its Holocene history is poorly understood, particularly in Central America. A high resolution (-3.8 years/sample) paleoclimate record of Central American rainfall variability has been reconstructed from a U /Th-dated stalagmite (7890 to 6490 yrs B.P.) from Costa Rica to constrain the onset and variability of ENSO throughout the Holocene, and to determine its role in generating regional climate anomalies. I suggest drier conditions, forced by El Nino, are represented by higher 5180 values, and are correlative with higher 513C values, indicating that …

The Provenance Of Eocene Tuff Beds In The Fossil Butte Member Of The Green River Formation Of Wyoming: Relation To The Absaroka And Challis Volcanic Fields, Matthew R. Chandler

Theses and Dissertations

The Green River Formation was deposited between 53.5 and 48.5 Ma. The Angelo, Fossil Butte, and Lower members of the Green River Formation at Fossil Basin, preserve ash fall tuffs deposited in ancient Fossil Lake. 40Ar/39Ar dating of sanidine yielded eruptive ages of 51.29 ± 1.29 Ma and 52.20 ± 3.08 Ma for two of the tuff beds within Fossil Basin. Immobile element and mineral compositions of Fossil Basin tuffs indicate that most tuffs erupted from a subduction zone originally as rhyolites and dacites. X-ray diffraction analyses reveal that the tuffs' glassy matrices have been altered to illite, calcite, clinoptilolite, …

Geophysical Investigations And Groundwater Modeling Of The Hydrologic Conditions At Masaya Caldera, Nicaragua, Richard Eric Macneil

USF Tampa Graduate Theses and Dissertations

Masaya volcano, Nicaragua, has been the site of tremendous Plinian basaltic eruptions. Two eruptions ~6,500 and 2,250 BP formed the 6 kilometer (km) x 11 km, northwest trending Masaya caldera. The present day active Santiago Crater within the caldera is the site of persistent volcano degassing and occasional phreatic explosions. While the mechanism responsible for these phreatic explosions is unclear, one possible explanation is the interaction of groundwater with the shallow magma chamber beneath Masaya. This interaction with meteoric water is supported by the substantial steam discharge from the vent, which is significantly larger than other similar volcanoes in the …

A Stratigraphic And Geochronologic Analysis Of The Morrison Formation/Cedar Mountain Formation Boundary, Utah, Brent W. Greenhalgh

Theses and Dissertations

The Lower Cretaceous Cedar Mountain Formation preserves several vertebrate faunas and has the potential of providing critical timing information pertaining to Early Cretaceous dinosaurs and the Sierran magmatic arc. Historically, the Morrison/Cedar Mountain contact and the duration of the unconformity between them have been difficult or impossible to determine because 1) the formations were deposited in similar environments, 2) the basal Cedar Mountain Formation is composed of reworked Morrison Formation, and 3) there are no radiometric ages for the lower Cedar Mountain Formation. A stratigraphic study through central Utah reveals a diagnostic suite of pedogenic and sedimentologic characters across the …

Characterization Of Fracture Systems In Sublette County, Wyoming Using P-Wave And C-Wave 3d Seismic, Keith R. Johnson

Masters Theses

Birefringence of seismic shear waves has proven to be a useful tool for identifying fracture intensity and orientation in the subsurface. Naturally occurring fractures have been shown to contribute to the deliverability of natural gas production in some reservoir formations in Rocky Mountain sedimentary basins. A multicomponent 3D 3C seismic survey acquired on the southeastern end of Pinedale Anticline in Sublette County, Wyoming was mapped to characterize fault systems within the sedimentary section. The tectonic and depositional history in the study area was determined by literature search and by one-dimensional backstripping. Compressional and wrench fault systems were observed and mapped. …

Sedimentology And Stratigraphy Of The Pennsylvanian Saginaw Aquifer, Central Lower Michigan, U.S.A., Niah B. H. Venable

Masters Theses

The Saginaw Aquifer is an important bedrock aquifer serving the needs of over 400,000 people in the Tri-County area of the Central Lower Peninsula of Michigan. The aquifer is comprised of the Pennsylvanian Grand River and Saginaw Formations. This study focuses on expanding existing knowledge of the general sedimentologic and stratigraphic characteristics of these units using conventional geological methods including core analysis, local log to core correlation, local and regional log to log correlation, and biostratigraphy. Analysis of new core from the study area examines facies and depositional environments given cursory coverage in outcrop studies by past researchers.

Incised valley …

Field Studies Of Hydrophobic Filter Pack Performance In Free Product Monitoring And Recovery, Nathan J. Brandner

Masters Theses

Multiple field experiments were conducted to determine the performance of hydrophobic filter packs, compared to the hydrophilic industry standard filter pack in free product hydrocarbon recovery. Laboratory and field studies have been previously performed in support of enhancing free product hydrocarbon recovery with the use of hydrophobic filter pack designs. This study was an attempt to test the efficacy of using hydrophobic filter pack materials to enhance free product recovery.

Six recovery wells were installed at three field sites, each site utilizing a pair of recovery wells, one hydrophobic and one hydrophilic, to compare their performances. Fine-grained hydrophobic filter pack …

Geologic Map And Structural Analysis Of The Twin Rocks 7.5 Minute Quadrangle, Wayne County, Utah, Samuel C. Sorber

Theses and Dissertations

A new geologic map of the Twin Rocks 7.5 minute quadrangle primarily located within Capitol Reef National Park, south-central Utah, provides stratigraphic and structural detail not previously available. This map has also been instrumental in understanding the evolution and development of fluvial terraces associated with Sulfur Creek and the structural geology of the backlimb of the Miners Mountain uplift. Nine bedrock stratigraphic formations and eight types of Quaternary deposits were mapped throughout the quadrangle. Bedrock stratigraphy ranges in age from Permian to Jurassic. New details absent on previous geologic maps include members of the Chinle and Moenkopi Formations and the …

Wharves To Waterfalls: A Geographical Analysis Of The Massachusetts Political Economy: 1763 - 1825., David Joseph Doran

Geosciences Theses

This research assesses how political legislation served as the catalyst in the transformation of Massachusetts through four specific economic stages from 1763 to 1825: fishing, privateering, global maritime commerce, and textile manufacturing. The objective of this analysis is to examine how politics forced coastal merchants to invest their commercial wealth into the burgeoning interior textile industry of the New England hinterland. Vance's mercantile model best explains European settlement of New England since multiple communities developed along the Atlantic coastline of the Massachusetts Bay region. Boston, Salem, and Newburyport emerged as entrepots, which acted as intermediaries between Europe and the frontier. …

The Timing And Causes Of Illite Formation In The Cretaceous Marias River Shale, Disturbed Belt, Montana, Stephen Gerard Osborn

Geosciences Theses

The clay mineralogy data and K-Ar ages of I/S measured in this study agree with previous work conducted within the Disturbed Belt (Hoffman, 1976) and show that diagenetic I/S formed quickly at several different places in response to thrust sheet burial during the Laramide orogeny. The averages of concordant age values for clay sub-fractions separated from three bentonites of Cretaceous and Jurassic depositional age increase from southeast (53.6 Ma) to northwest (56.7 Ma) along the trend of the Disturbed Belt. This northwestward increase of mean ages of I/S is consistent with a thrust sheet emplacement model for the Disturbed Belt …

Petrogenesis Of Pleistocene Basalts In The Norris-Mammoth Corridor, Yellowstone National Park, Kristeen Marie Bennett

UNLV Theses, Dissertations, Professional Papers, and Capstones

The basalts of the Norris-Mammoth corridor within the Yellowstone Plateau volcanic field have an outcrop erupted volume of ~94 km³. Basalt in the Yellowstone Plateau volcanic field is minor in volume compared to 3,700 km³ of felsic lavas, domes, and pyroclastic rocks. The tholeiitic eruptive products formed small Hawaiian-style shield volcanoes. A newly identified volcanic vent, called the Panther Creek vent, within the Swan Lake Flat basalt stratigraphic unit, was primarily Strombolian in its eruption style. This vent is the first recognized cinder cone in Yellowstone National Park.

All basaltic units within the Norris-Mammoth corridor, and the …

Contact Metamorphism Of Calc-Silicate Rocks In The Belmont Contact Aureole, Central Nevada, Kelly Plummer

Masters Theses

This study focuses on the contact metamorphism of the Ordovician Zanzibar and Toquima Formations by the Cretaceous Belmont Pluton in central Nevada. I mapped the distributions of tremolite and diopside to determine the location of isograds. These isograds are the result of the reactions: 8 quartz + 5 dolomite + H₂O = 3 calcite + tremolite + 7 CO₂ and tremolite + 2 quartz + 3 calcite = 5 diopside + 3 CO₂ + H₂O. Pressure of metamorphism is estimated at between 4 kbar and 1 kbar, but is not definite because of uncertainty …

Origin And Classification Of Middle Wallace Breccias, Mesoproterozoic Belt Supergroup, Montana And Idaho, Quintin M. Overocker

Masters Theses

A series of enigmatic breccias in the Wallace Formation, Mesoproterozoic Belt Supergroup, have been variously interpreted as originating from: (1) syndepositional downslope slumping; (2) syndepositional evaporite dissolution and collapse; or (3) post- depositional tectonic faulting. Each hypothesis carries its own implications regarding the depositional and diagenetic history of the Belt basin. Examination of several Middle Wallace breccia outcrops suggests that they can be grouped into two distinct categories based on size of breccia bodies, clast size, and relationships with surrounding strata, and matrix composition. Results indicate that rather than a single origin, these two breccia groups originate from distinctly different …

Lower Paleozoic Sequence Stratigraphy, Deposystems And Paleogeography Of Northwestern Ordos Basin, North China, Benjamin J. Kessel

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The Ordos basin rests upon the North China Block and is one of the largest sedimentary basins in north China, with more than 15 km of Phanerozoic strata. Published estimates suggest that over 2000 m of carbonates and lesser amounts of siliciclastics were deposited on the North China Carbonate Platform (NCCP) from the Lower Can1brian through the Middle Ordovician. However, lower Paleozoic facies successions and deposystems of northwestern Ordos basin remain poorly represented in western literature. This paper constrains depositional environments, lithologies, facies relationships and sea-level history of the northwestern part of the North China block (NCB) in an effort …