Physical Sciences and Mathematics Commons^™

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 …

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 …

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 …

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 …

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 …

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 …