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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. …

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 …

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 …

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 …

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 …

Azimuthal Seismic First-Arrival Tomography As A Proxy For Hydraulically Conductive Subsurface Fracture Networks, Matthew Brooks Edmunds

Masters Theses

The Oak Ridge Field Research Center (ORFRC) was established by the Environmental Sciences Division (ESD) at the Oak Ridge National Laboratory (ORNL) in Oak Ridge, TN, in order to study the various biogeochemical processes involved in the remediation as well as natural attenuation of a large contaminant plume that is extant in the vicinity of the ORIFRC. A part of this work has been to characterize the movement of this groundwater/contaminant plume with the use of azimuthal seismic first-arrival tomography (ASFT).

Within the general area of the ORIFRC, a 0-2 m layer of generally isotropic anthropogenic fill and unconsolidated soil …

Co2 Injection Into A Deep Saline Aquifer: Porosity Measurements, Numerical Modeling, And Costs Associated With Uncertainty Of Petrophysical Parameters, Michael John Gragg

Masters Theses

Anthropogenic levels of atmospheric greenhouse gases, particularly carbon dioxide (CO₂) have increased rapidly over the last several decades and coincide with rising temperatures globally. One possible solution is to capture CO₂ before it is released into the atmosphere by large point sources, such as fossil fuel power plants. Once captured, the CO₂ can be condensed and transported to a storage facility. Of the available options for storage of condensed CO₂, geologic sequestration in deep saline aquifers is considered the most viable option.

Porosity measurements were obtained for nearly 100 core samples of the Knox …

Testing A Novel Technique To Improve Aluminum-26 Accelerator Mass Spectrometry Measurements For Earth Science Applications, Meghan Sarah Janzen

Masters Theses

The measurement of cosmogenic ²⁶Al [aluminum-26] in geological samples by accelerator mass spectrometry (AMS) is typically conducted on Al₂O₃ [aluminum oxide] targets. However, Al₂O₃ is not an ideal source material because it does not form a prolific beam of Al^- [negative atomic aluminum ions] required for measuring low-levels of ²⁶Al. This thesis presents the performance of AlN [aluminum nitride], AlF₃ [aluminum fluoride] and mixed AlN + Al₂O₃ as novel alternative source materials for the analysis of ²⁶Al. A negative ion cesium sputtering source at the Holifield …

Characterization Of Wetting Front Geometry And Fluid Migration In The Vadose Zone Using Surface Time-Lapse Seismic First-Arrival Tomography, Rachel Elizabeth Storniolo

Masters Theses

Characterizing and quantifying vadose zone parameters and processes are critical for assessing environmental, agricultural, and engineering problems. The shallow subsurface is essential to the geologic and hydrologic cycles because it supports agriculture and ecosystems, influences water resources, and acts as a repository for contaminants. Fluid migration in the vadose zone is dependent on a number of soil characteristics (e.g. soil type and saturation). Quantifying parameters is often the primary goal of hydrological fluid-flow investigations; however, the values calculated can be misrepresentative of the subsurface due to anisotropic features. Hydraulic conductivity (K), the most common quantitative parameter used to describe fluid …

Investigating The Evolution Of Two Southern Appalachian Terrane Boundaries And A Plutonic Complex: Tectonic Implications Of Structural, Geochemical, And Geochronologic Studies In The Central Georgia Inner Piedmont, Christopher William Howard

Masters Theses

Detailed geologic mapping in the central Georgia Inner Piedmont has revealed a plutonic complex in the Cat Square terrane (CST) between the Brindle Creek and Towaliga faults ~80 km SE of Atlanta. The complex has an area ~235 km² and is composed of two distinct mappable granitoids. The High Falls Granite (HFG) is a Siluro-Devonian (424-380 Ma) porphyritic granite with characteristic blocky microcline megacrysts. The Indian Springs Granite (ISG, 313-299 Ma) has an equigranular, fine- to medium-grained texture. Some foliation in the HFG is concordant with regional trends, but a relict magmatic or secondary tectonic foliation was also observed …

Structural Control Of Fluvial Network Morphology On Titan, Sarah Alice Drummond

Masters Theses

Titan fluvial networks have been classed based on identification of network pattern morphology. Drainage network patterns have specific geologic implications, as the pattern is affected by regional slope, structures, and bedrock resistance. Qualitative identification of network patterns has resulted in a lack of consistent classifications for networks. In this work, a global map of fluvial features on Titan is presented with features delineated based on their appearance in Cassini Titan Radar Mapper synthetic aperture radar (SAR) data. The networks imaged by the Huygens Descent Imager/Spectral Radiometer (DISR) are also included in this work. Networks were classified using a quantitative terrestrial …

Mussel Survivorship, Growth Rate And Shell Decay Rate In The New River Basin Of Tennessee: An Experimental Approach Using Corbicula Fluminea, Grant Andrew Mincy

Masters Theses

The New River Basin (NRB) of Tennessee is home to a number of rare endemic aquatic communities. One such community of particular importance to the area, experiencing a precipitous population decline due to the fouling and pollution of their freshwater systems, is that of freshwater mussels (Bogan 2006). This study in the NRB involves measuring the mortality rates of live Asian clams (Corbicula fluminea) assemblages and the shell decay rates of their death assemblages. This study also examines the decay rates of the native Villosa iris to gather information on molluscan health and the ability of their shells …

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 …

Structural And Stratigraphic Relationships Near The Southern Terminus Of The Pulaski Fault, Northeast Tennessee, Phillip Michael Derryberry

Masters Theses

The Pulaski fault is one of the master thrust faults in the Appalachian Alleghanian fold-thrust belt. Detailed geologic mapping of Cambrian and Ordovician strata in northeastern Tennessee revealed key structural and stratigraphic characteristics for distinguishing the Pulaski thrust sheet from its footwall, the Saltville thrust sheet. Unlike most thrust systems in the Valley and Ridge, the Pulaski records at least two deformation phases. Geometric and crosscutting relationships along parts of the Pulaski thrust sheet in this study area and in southwestern Virginia suggest hanging wall and possibly some footwall deformation prior to the emplacement of the thrust sheet. The initial …

Late Pleistocene And Holocene Hydroclimate Change In The Southeastern United States: Sedimentary, Pedogenic, And Stable Carbon Isotope Evidence In Tennessee River Floodplain Paleosols, James Joseph Kocis

Masters Theses

In order to understand hydroclimate variability of future climate change, it is important to know the timing and range of natural climate change in the past. The Southeastern United States (SE) is situated along the poleward extent of projected subtropical drying, where the expression of past hydrological balances remains unclear. The lack of high-resolution paleohydroclimate records in the SE forces climate modelers to base interpretations on better-understood regions of North America. The SE likely experienced significant changes in precipitation regimes resulting from its position at the convergence of several oceanic and continental air masses. To reconstruct precipitation variability, this study …

Aeolian Simulations: A Comparison Of Numerical And Experimental Results, With Projections For Titan., Oscar Lee Mathews

Masters Theses

Aeolian processes are major determinants of geomorphology on bodies in the Solar System possessing an atmosphere-surface interface and transportable sediment, including Earth, Mars, Venus, and Titan. Substantial efforts have been made over the last few decades to understand these processes using specialized wind tunnels, field studies, and, more recently, numerical simulations. This thesis describes a model of aeolian sediment transport using computational fluid dynamics (CFD), and compares the results with those obtained in the Martian Surface Wind Tunnel (MARSWIT) testing conducted in the Planetary Aeolian Laboratory at NASA Ames Research Center. The ultimate goal of the thesis was to develop …

Processes Controlling The Composition Of First-Cycle Sediments Deposited In An Arid-Climate, With Implications For Provenance Reconstruction Studies, Aubrey Lynn Modi

Masters Theses

Petrologic analysis of first-cycle clastic sediments derived from a single source in an arid environment provides a means to determine how well they resemble the petrology and geochemistry of their source. The Stepladder Mountains, located in the Mojave Desert of southeastern California, represents a well-controlled location (i.e., arid environment; single, known source; short transport distance) to examine how naturally formed sediments acquire their compositions. Compositional modifications associated with sediment production were resolved through direct examination of the weathered components (regolith, grus, and sediments). Sediment compositions strongly vary by grain size, indicating that, after the source itself, hydrodynamic sorting played the …

Constraining Martian Sedimentation Via Analysis Of Stratal Packaging, Intracrater Layered Deposits, Arabia Terra, Mars, Sarah Beth Cadieux

Masters Theses

Craters within Arabia Terra, Mars, contain hundreds of meters of layered strata

showing systematic alternation between slope- and cliff-forming units, suggesting either

rhythmic deposition of distinct lithologies or lithologies that experienced differential

cementation. Hypothesized origins of these intercrater layered deposits include

lacustrine, aeolian, volcanic airfall, and impact surge deposition. On Earth, rhythmically

deposited strata can be examined in terms of stratal packaging, wherein the interplay of

tectonics, sediment deposition, and change in base level results in predictable patterns

with respect to changes in the amount of space available for sediment accumulation.

Fundamental differences between tectonic regimes of Earth and Mars …

Sedimentologic And Stratigraphic Analysis Of Units Defining The Basal Sauk Supersequence Across The Craton Margin Hinge Zone, Southeastern California, Eric Gordon Hogan

Masters Theses

In the Death Valley and Mojave Desert regions of southeastern California, the contact separating the lower and middle members of the Wood Canyon Formation (WCF) is currently interpreted as a regional scale unconformity coincident with the base of the Sauk Sequence. Regional mapping of this surface, however, reveals a nonconformable contact with underlying crystalline basement in cratonic settings, and a relatively conformable contact atop a northwest thickening wedge of miogeoclinal strata that is capped by the lower member of the WCF. Consistent with an unconformity, the progressive loss of three carbonate units within the lower member of the WCF has …

Transport Of Explosive Residue Surrogates In Saturated Porous Media, Bethsheba Lavoie

Masters Theses

Contamination of soils by munitions constituents is pervasive on Department of Defense operational ranges. Low-order detonations result in the heterogeneous distribution of explosives residues (ER) at shallow depths. At a limited number of ranges ER contamination of groundwater has been observed.

Previous studies have shown that the downward migration of colloid-sized contaminants can significantly impact groundwater quality. The goal of this study was to investigate if colloid transport plays a role in the migration of ER contaminants. Our primary objective was to determine the transport potential of fine (<5>um) ER particles under ideal conditions for colloid transport. A secondary …

The Effects Of Changes In Water Content On Uranium(Vi) Leaching In Sediment Mixtures Containing Gravel, Andrew Weber Moore

Masters Theses

This study is aimed at understanding the physical and chemical effects that changes in water content have on uranium leaching in sediment containing gravel. It was hypothesized that leaching will be more efficient under unsaturated conditions because flow will be restricted to the smallest pores and will have the most contact with the uranium contaminated sediment. Under saturated conditions, a large portion of the flow will bypass the < 2 mm material, and in turn not come into contact with uranium contaminated material. Batch adsorption and desorption experiments were performed on < 2 mm ERDF sediment to determine the linearity and reversibility of sorption processes and to aid in the interpretation of the leaching experiments. Results of the desorption experiments on aged, contaminated sediments show that the mass percent of sorbed U(VI) released to solution decreased as the sorbed concentration of U(VI) decreased. The opposite trend was observed on freshly contaminated sediments. This indicated that aging increased U(VI) affinity for the solid phase and was attributed to either the crystallization of calcite, which incorporated a portion of the sorbed U(VI) as it crystallized, or the presence of voids in basaltic lithic fragments accessed by diffusion. Column leaching experiments were performed at two water contents on artificially contaminated sediment collected from the Department of Energy’s (DOE) Hanford Site, Washington state. The sediment contained 81.3% gravel (> 2 mm) by mass. Non-reactive tracers were well fit with the convection-dispersion equation (CDE) at both high and low water contents indicating physical equilibrium. The column experimental data were fitted to an …

Tectonic Evolution Of The West-Central Portion Of The Newton Window, North Carolina Inner Piedmont: Timing And Implications For The Emplacement Of The Paleozoic Vale Charnockite, Walker Top Granite, And Mafic Complexes, Heather Elizabeth Byars

Masters Theses

Detailed geologic mapping of portions of the Banoak, Reepsville, Lincolnton West, and Cherryville 7.5-minute quadrangles has confirmed the easternmost exposure of the Brindle Creek fault, which frames the Newton window. The Brindle Creek fault is a terrane boundary that separates the overlying Siluro-Devonian assemblage of metasedimentary rocks and Devonian-Mississippian anatectic plutons of the Cat Square terrane from the Neoproterozoic(?)-Ordovician metasedimentary and igneous rocks of the Tugaloo terrane. Structures related to six deformational events have been identified in this portion of the Inner Piedmont. The Brindle Creek fault has been folded multiple times, resulting in a sinuous outcrop pattern and the …

Tectonic Evolution Of The Southern Appalachian Inner Piedmont: Identification And Interpretation Of Crustal Features From Aeromagnetic Data And Detailed Geologic Mapping In Central Georgia, Brittany Allison Davis

Masters Theses

The Inner Piedmont (IP) is the Neoacadian migmatitic orogenic core of the southern Appalachians, exhibiting the widest area of high-grade metamorphism; regional upper amphibolite facies with isolated pods of granulite grade metamorphism. Peak P-T conditions in central GA reached 4.0-7.6 kbars and 630-715 ̊ C. The Brindle Creek fault (BCf) separates high-grade metasedimentary rocks of the eastern Tugaloo terrane (Tt) and Cat Square terrane (CSt). The Tt consists of the Neoproterozoic to early Paleozoic(?) Tallulah Falls Formation, Chauga River Formation, and the Mid-Ordovician Poor Mountain Formation, intruded by Early to Middle Ordovician granitoids. The CSt consists of Siluro-Devonian metasedimentary rocks, …

Fluorescence Characterization Of Karst Aquifers In East Tennessee, Teresa L. Brown

Masters Theses

Karst and fractured rock aquifers are primary sources of drinking water in the Appalachian region, even though most are inherently susceptible to surface-derived contamination. Many of the obstacles to water supply protection in such systems could be alleviated through the use of tracer testing to delineate recharge areas and surface-to-groundwater connections. Tracer testing is currently under-utilized, however, due to public safety concerns and ambivalence on the part of regulatory agencies. This study aimed to address this issue through a characterization of the fluorescent properties of typical carbonate aquifers for the purpose of refining the timing and design of low-concentration dye …

Relationship Between Slug-Test And Effective Hydraulic Conductivities For 2-Dimensional Heterogeneous Aquifers, Richard Walker Donat

Masters Theses

Slug tests are one of the most common field tests used by hydrogeologists to evaluate the hydraulic conductivity of an aquifer system. Steady-state and transient (slug test) numerical simulations were run in 37, 2-dimensional randomized multifractal hydraulic conductivity fields. Each field consisted of 59,049 individual saturated hydraulic conductivity (K) values with varying numbers of hydrofacies and different degrees of spatial heterogeneity. The K_eff values were determined by examining the flux in and out of the steady-state numerical model. The K_slug values were determined by adding a slug of water to the center node of the field and evaluating …

Ground Penetrating Radar Investigations On The Relationship Between Horizontal Sub-Wavelength ‘Thin-Layer’ Bedrock Fractures And Reflection Amplitudes, Kevin E. Burns

Masters Theses

Several theoretical equations that predict sub-wavelength ‘thin-layer’ reflection amplitudes are compared to the results of a series of controlled ground penetrating radar surveys using 1 GHz transducers over a physical model of a horizontal bedrock fracture. Two large plastic (UHMW-PE) blocks, separated by one or more stacked inserts (polyethylene; ~0.1 mm thick) for a total of 101 surveys, generate a modeled fracture with an aperture ranging from 0-300 mm. All existing theoretical reflection coefficient equations fail to predict observed reflection amplitude oscillations in the data when the fracture aperture is less than 1/48 of a wavelength. The only theoretical formulation …

Amino Acid Analysis Of Marine Sediments, Hauraki Gulf, New Zealand, Tabbatha A. Cavendish

Masters Theses

Amino acid compositions, bulk organic carbon, total nitrogen, and total organic matter were measured for eight sediment samples from the Hauraki Gulf, New Zealand, in order to assess the source and fate of organic matter in a shallow marine environment. Samples were collected from near-shore and off-shore shore sites, as well as from a site receiving freshwater input from multiple rivers. A comparison of carbon, nitrogen, and amino acid compositions of samples between 1 cm depth (Uhle 2004) and 5 cm depth was used to assess changes in organic matter composition through time. Amino acid analyses in particular should be …

Tectonometamorphic Evolution Of The Eastern Blue Ridge: Differentiating Multiple Paleozoic Orogenic Pulses In The Glenville And Big Ridge Quadrangles, Southwestern North Carolina, Donald W. Stahr

Masters Theses

New field and analytical data collected in the eastern Blue Ridge (EBR) of southwestern North Carolina reveal a complex, polyphase thermotectonic history, and delimit the timing of previously unrecognized orogenic pulses in a portion of the southern Appalachian orogenic core. Detailed geologic mapping of the Glenville and Big Ridge 7.5’ quadrangles delineated the location of the Chattahoochee fault, a tectonic boundary separating the western Tugaloo terrane from distinct central Blue Ridge terranes.

Zircon geochronologic data for two EBR granitoids in the map area indicate emplacement occurred at ~335 Ma, making these plutons among the youngest recognized in the EBR. Bulk-rock …

Major And Trace-Element Chemistry Of Minerals In Lithologies A And B In Martian Meteorite Eeta79001: Petrogenesis Revisited, Michael Joseph Mellin

Masters Theses

EETA79001 is a unique shergottite composed of two mafic lithologies (termed LithA and LithB) that are separated by an igneous contact. Both lithologies have basaltic compositions; however, LithA contains megacrysts of olivine, orthopyroxenes, and chromite whereas LithB does not; also, LithA is finer-grained than LithB. Currently, the literature is in disagreement regarding the formation of this unique meteorite, especially regarding LithA. Different formational theories (e.g. fractional crystallization, magma mixing, assimilation, and impact melting) have their own constraints (chemical, thermal, or petrographic). This study uses petrographic observations combined with major- and trace- element compositions within minerals to investigate the petrogenesis of …

Factors Influencing Persistence Of Fecal Bacteroides In Stream Water, Alyssa K. Bell

Masters Theses

Fecal contamination leads to increased risk of exposure to enteric pathogens in aquatic environments used for drinking water, recreation, and commercial shellfishing. Current indicators of fecal contamination recommended by the EPA such as E. coli and enterococcus can fall short of meeting ideal indicator criteria by having widely-varying persistence in the environment, reproducing in the environment, occurring in the gut in low and variable concentrations, and requiring time-consuming assays. Furthermore, both these indicators lack the degree of host specificity needed for use in identifying sources of fecal contamination, which is an important tool for identifying and reducing fecal inputs to …