Physical Sciences and Mathematics Commons^™

Species Discrimination, Systematics, And Ontogeny Of Blastoidea, James William Atwood

Doctoral Dissertations

Blastoids are ideal model organisms with which to study evolutionary processes because nearly all of the skeletal elements are shared among all taxa, there have been recent advances in the understanding of blastoid homology, and they are more commonly preserved fully inflated than any other blastozoan. Because of this homology and preservation, blastoids are the perfect candidate for studies involving geometric morphometrics and systematics. But the potential of blastoids to be a model clade has been extremely hampered by the lack of a modern phylogenetics and classification.

The focus of this dissertation is to increase our understanding of blastoid species …

Hydrogeology Of The Little River Animal Agriculture Environmental Research Unit And Impacts Of Dairy Operations On Groundwater, Robert Wesley Hunter

Masters Theses

This thesis describes the development of an integrated hydrogeologic/hydrologic site assessment and groundwater/surface water quality monitoring program at the University of Tennessee – Little River Dairy Farm, located near Townsend, TN. Hydrologic/hydrogeologic investigations of streams and groundwater at the site have been underway for more than 5 years, and these are expected to provide background data for assessing impacts of dairy wastes. The lower half of the ~180 ha site consists of low-relief fields used for row crops, which are underlain by 4 – 9 m of alluvial deposits on top of black shale or limestone that include sinkhole features. …

Scale-Dependent Heterogeneity In Fracture Data Sets And Grayscale Images, Ankur Roy

Doctoral Dissertations

Lacunarity is a technique developed for multiscale analysis of spatial data and can quantify scale-dependent heterogeneity in a dataset. The present research is based on characterizing fracture data of various types by invoking lacunarity as a concept that can not only be applied to both fractal and non-fractal binary data but can also be extended to analyzing non-binary data sets comprising a spectrum of values between 0 and 1. Lacunarity has been variously modified in characterizing fracture data from maps and scanlines in tackling five different problems. In Chapter 2, it is shown that normalized lacunarity curves can differentiate between …

Genetic Analysis Of Bacterial Gene Variations In Sulfidic Springs And The Influence On Geochemistry, Brendan Joseph Headd

Doctoral Dissertations

Culture-independent methods have revolutionized environmental microbiology and geomicrobiology studies and next-generation sequencing and metagenomics techniques continue to reveal the vast genetic diversity of microorganisms. But, these approaches provide comparatively little quantitative information about the roles that naturally occurring microbial gene variations play in local biogeochemical cycling. The goal of this study was to identify how the physical distribution and genetic diversity of microbial genes within a habitat impact environmental geochemistry by examining the biogeography of 16S rRNA genes and bacterial sulfur oxidation (Sox) genes in terrestrial sulfidic springs. 16S rRNA gene pyrosequences were obtained from microbial mats inhabiting eight sulfidic …

Detailed Geologic Studies Of Paleoseismic Features Exposed At Sites In The East Tennessee Seismic Zone: Evidence For Large, Prehistoric Earthquakes, Kathleen Frances Warrell

Masters Theses

The East Tennessee seismic zone (ETSZ) is the second most active in the eastern United States, but recorded earthquakes do not exceed M_w [moment magnitude] = 4.6. Earthquake epicenters are located 5-26 kilometers deep in autochthonous basement, and faults producing these earthquakes do not break the surface. Detailed paleoseismic investigations at sites within the ETSZ include: detailed geological mapping, trenching, aerial photograph reconnaissance, X-ray diffraction (XRD), grain-size analysis, and optically stimulated luminescence dating of alluvium.

Site DL-6 near Dandridge, Tennessee, reveals a complex array of features providing evidence that at least 4‒6 M_w > 6 earthquakes affected the area. …

Martian Dune Fields: Aeolian Activity, Morphology, Sediment Pathways, And Provenance, Matthew Chojnacki

Doctoral Dissertations

Wind has likely been the dominant geologic agent for most of Mars’ history. The wide-spread nature of sand dunes there shows that near-surface winds have commonly interacted with plentiful mobile sediments. Early studies of these dunes suggested minimal activity, dominantly unidirectional simple dune morphologies, and little variations in basaltic sand compositions. This dissertation examines martian sand dunes and aeolian systems, in terms of their activity, morphologies, thermophysical properties, sand compositions, geologic contexts, and source-lithologies using new higher-resolution orbital data. Although previous evidence for contemporary dune activity has been limited, results presented in Chapter II show substantial activity in Endeavour Crater, …

Quantitative Integration Of Multiple Near-Surface Geophysical Techniques For Improved Subsurface Imaging And Reducing Uncertainty In Discrete Anomaly Detection, Megan Estelle Carr

Doctoral Dissertations

Currently there is no systematic quantitative methodology in place for the integration of two or more coincident data sets collected using near-surface geophysical techniques. As the need for this type of methodology increases—particularly in the fields of archaeological prospecting, UXO detection, landmine detection, environmental site characterization/remediation monitoring, and forensics—a detailed and refined approach is necessary. The objective of this dissertation is to investigate quantitative techniques for integrating multi-tool near-surface geophysical data to improve subsurface imaging and reduce uncertainty in discrete anomaly detection. This objective is fulfilled by: (1) correlating multi-tool geophysical data with existing well-characterized “targets”; (2) developing methods for …

Metamorphic Phase Equilibria In A Contact Aureole: Tres Hermanas Mountains, Luna County, New Mexico., Carissa Dawn Snyder

Masters Theses

To characterize the metamorphism in the Tres Hermanas Mountains contact–metamorphic aureole in Luna County, New Mexico, I mapped and collected samples of the Paleozoic strata near the quartz monzonite pluton along the northeast flank of North Peak. Stratigraphy in this area includes the Pennsylvanian undivided unit that is composed of thin-medium interbedded limestone, shale, and sandstone and the Hueco Formation that could be broken out into four members: a pebble–cobble conglomerate marks the base, a medium to massive bedded siliceous limestone is next, followed by a pure limestone member and topped by a breccia bed in places marking the fault …

Emplacement Mechanisms And Magma Driving Pressure Of The Proterozoic Curecanti Pluton; The Black Canyon Of The Gunnison, Colorado, Gordon Leonard Hicks

Masters Theses

There is significant obliquity between the margins of the Curecanti pluton, an internal foliation, a coeval swarm of ~400 pegmatite dikes just west of the pluton, and the host rock foliation. This pluton is a 5 km-long, 3 km-wide, and 0.4 km-thick sheet of monzogranite exposed in the Black Canyon of the Gunnison, CO. The pluton is discordant along most of its length, but has a >100-m-thick root at its western margin subparallel to the foliation in the host rock gneisses. A cordierite + anthophyllite + staurolite + garnet schist from the Vernal Mesa pluton aureole was previously dated (1.4 …

Quantifying The Relationship Among Ground Penetrating Radar Reflection Amplitudes, Horizontal Sub-Wavelength Bedrock Fracture Geometries, And Fluid Conductivities, Carolyn Morgan Tewksbury-Christle

Masters Theses

Accurate characterization of subsurface fractures is indispensible for contaminant transport and fresh water resource modeling because discharge is cubically related to the fracture aperture; thus, minor errors in aperture estimates may yield major errors in a modeled hydrologic response. Ground penetrating radar (GPR) has been successfully used to noninvasively estimate fracture aperture for sub-horizontal fractures at outcrop scale, but limits on vertical and horizontal resolution are a concern. Theoretical formulations and field tests have demonstrated increased GPR amplitude response with the addition of a saline tracer in a sub-millimeter fracture; however, robust verification of existing theoretical equations without an accurate …

Metamorphism, Kinematic Evolution, And Timing Constraints Of The Greenbrier Fault Around The Ela And Bryson City Domes, North Carolina, Remington M. Leger

Masters Theses

Field mapping, microstructural analysis, and electron microprobe analysis were performed on rocks from the Bryson City and Ela domes, North Carolina, to help constrain the tectonic history of the region. The domes are en echelon northeast-trending antiformal structures formed by two perpendicular sets of folds. They are bounded by the Greenbrier fault, which forms a ductile shear zone that juxtaposes the Great Smoky Group in the hanging wall with Grenville basement in the footwall. Isoclinal folds (F2) and axial planar foliation (S2) characterize the regional deformation (D2). Inter- to syn-kinematic porphyroblasts (relative to D2) of kyanite, staurolite, and garnet grew …