Digital Commons Network^™

Biodegradation Of Petroleum Hydrocarbons In Contaminated Coastal Environments, Nigeria, Samson Onibiyo

Geosciences Theses

ABSTRACT

To compare the degree of biodegradation of petroleum hydrocarbons in sediments from Ikarama and Okwori in the Niger delta, Nigeria, concentrations of n-alkanes and polycyclic aromatic hydrocarbons in the sediments were measured. Analysis was conducted with gas chromatography using mass spectrometry detector. While the decrease in concentrations of n-alkanes and polycyclic aromatic hydrocarbons confirmed the process of biodegradation in the sediments it was not solely fit to substantiate the degree of biodegradation in the sediments. Hence the percentage proportion of n-alkanes and polycyclic aromatic hydrocarbons was used. The degree of biodegradation of n-alkanes in both Okwori and Ikarama was …

An Evaluation Of Late Holocene Sea Level Rise And Anthropogenic Impacts; Jones Narrows Marsh, Chatham County, Georgia, Jessie Hughes

Geosciences Theses

A detailed record of the Late Holocene sea level rise and landscape evolution that has taken place on the Georgia coast is contained within the sedimentary stratigraphy of its salt marsh depositional basins. Global relative sea level (RSL) has risen during the Late Holocene, and the rate of rise has accelerated during the Anthropocene. Jones Narrows marsh stratigraphy and radiocarbon analysis indicate increasing rates of RSL rise for the late Holocene on the Northern Atlantic Coast of Georgia, while FPXRF analysis of the marsh sediments facilitates a chemostratigraphic study of Jones Narrows salt marsh deposition and landscape evolution. Sedimentation and …

A Study Of Mineral Impurities Within The Georgia Kaolins, Daniel J. Gardner

Geosciences Theses

The mining industry located along the fall line region of central Georgia has been and remains as one of the largest global exporters of the clay mineral kaolinite. Among the kaolin deposits in that region, the Cretaceous Buffalo Creek formation and the Eocene Jeffersonville member contain the most commercially viable kaolin to extract and process for resale. The minerals of the sand and silt fractions of these kaolin units were separated via dense liquid separation and analyzed for comparison by X-ray diffraction, scanning electron microscopy, and elemental analysis. The dense fractions are enriched in select heavy minerals (zircon and rutile) …

Investigating The Effect Of Aluminum Substitution On The Physical And Chemical Properties Of Ferrihydrite, Richard Ajewole

Geosciences Theses

This thesis investigated the impact of aluminum (Al) substitution in ferrihydrite (FH) on both its chemical and physical properties. Al was coprecipitated with FH under controlled hydrolysis conditions to yield various % mol substitutions. Sulfate adsorption was measured across pHs to examine any changes in surface reactivity. The samples’ morphology, specific surface areas (SSAs), crystallinity, and phase transformation upon heating were evaluated and parameterized to allow conclusions on the role of Al on the physical properties. Sulfate sorption diminished across pHs for all Al saturation levels. X-ray Diffraction revealed goethite (GT) presence was negatively influenced by Al. The SSAs of …

Surface Charge Characterization Of Anatase And Rutile Using Flow Adsorption Microcalorimetry, Tyler Hawkins

Geosciences Theses

Titanium dioxide (TiO₂) attracts extensive attention due to its widespread technological and environmental applications. This study seeks to investigate the surface charging behavior of the two TiO₂ polymorphs, anatase and rutile, using Flow Adsorption Microcalorimetry (FAMC). FAMC allows direct quantitative measurement of the heat of a surface reaction; these calorimetric heats are directly proportional to the surface charge. Determining the magnitude of positive and negative charges at the surface over a range of pHs allows for the determination of the point of zero net charge (PZNC) via a unique calorimetric method that removes many of the shortcomings …

Geographic Variation Of Radon Gas Concentrations In Relationship To Housing Characteristics In Dekalb County, Georgia, Fredrick Neal

Geosciences Theses

Radon (RN-222), naturally released from underground, is the second leading cause of lung cancer for at-risk groups after smoking, and the leading cause of lung cancer. This research aims to investigate the relationship between housing characteristics and indoor radon levels. Indoor radon data (1993 – 2013) were obtained from the DeKalb County Board of Health alongside housing characteristics sourced from the DeKalb County Tax Assessor. Chi-square tests, logistic regression, and bivariate analysis were used to examine the housing risk factors. The results indicate a correlation between high radon concentrations, and homes constructed of brick, with a basement foundation and centralized …

Effects Of Urbanization On Stream Flashiness In The I-85 Corridor Of The Southeastern Piedmont, Eli Koslofsky, Katie Price, C. Rhett Jackson

Geosciences Theses

The metro areas of the southeastern Piedmont are rapidly expanding, bringing changes to the hydrology of the watersheds within them. Increased urbanization can have significant effects on stream hydrology within a watershed, including large fluctuations of flow in streams referred to as “stream flashiness”. Increased stream flashiness has numerous consequences, including water quality degradation, flooding, and destruction of aquatic habitats. This thesis quantifies stream flashiness in urban and rural streams and investigates the relationship between flashiness and watershed land cover, particularly the amount and spatial distribution of impervious surfaces. Results show a strong relationship between urbanization and peak flows, but …

The Evaluation Of Measuring Stream Channel Morphology Using Unmanned Aerial System-Based Structure-From-Motion Photogrammetry, William Ballow

Geosciences Theses

As part of a collaborative project at a stream segment reach on Proctor Creek in Atlanta, GA, UAV-based SfM photogrammetry was tested as a method for collecting fluvial topographic data relative to traditional USGS total station surveying methods. According to the USGS method, 11 transects were surveyed, and imagery was collected via a UAV to create a SfM DEM. The resulting DEM was incomplete but showed promise for the SfM method. Two additional stream segments were chosen in the Atlanta area, the first along SFPC in DHCL and the second along NFPC near Buford Hwy. For each site 11 transects …

Deciphering Phosphorus And Aluminum Physiochemical Associations In Paleolake Sediments Of Long Pond, Ga, Christopher Tidwell

Geosciences Theses

This study focuses on Long Pond, a groundwater-fed sinkhole lake in Georgia, which does not exhibit any evidence of eutrophication drivers despite high concentrations of sedimentary phosphorus (P) (> 3000 mg/kg P) in the recent sediment record. Chemical analyses have shown a strong correlation (r²>0.99) between P and aluminum (Al) throughout the core, suggesting Al plays a significant role in sequestering most of the P, and limiting its availability to phytoplankton, thereby inhibiting eutrophication. The purpose of this study is to decipher P and Al physicochemical associations in the sediments. After the samples were fractionated into amorphous and …

Land Management Controls On Hydraulic Conductivity Of An Urban Farm In Atlanta, Ga, Hayden Hinton

Geosciences Theses

Increasing urbanization is often accompanied by problematic changes in watershed hydrology. Decreasing surface permeability can lead to increased overland flow volumes, which may spread surficial contaminants and increase the strain on municipal stormwater infrastructure. This study examines a mixed-use property in the Proctor Creek watershed in Atlanta, Georgia, to better understand how land-management practices influence soil overland flow potential. Field saturated hydraulic conductivity (Kfs) measurements were collected from soils 1) subjected to compaction, 2) in urban agricultural use, and 3) under common lawn maintenance. Mean values were 9.1E-7 cm/s, 2.2E-4 cm/s, and 9.0E-6 cm/s respectively. Measurements were collected in-situ with …

Spatial Analysis Of Environmental Factors Affecting Endangered And Invasive Fish Species On The Belize Barrier Reef, Adam S. Acker

Geosciences Theses

The second largest reef in the world is experiencing a dramatic change in its environment with continued development and an influx in tourism having a direct impact on the physical and ecological balance of the reef. The introduction of hazardous materials and practices have contributed to reef degradation through excess sedimentation, overfishing, and increased shipping and have the ability to influence some of the reef’s most endangered inhabitants. A spatial examination using multiple variables impacting changes in certain populations of endangered and invasive fish species are studied, incorporating integrated species abundance and sighting data as well as potential environmental threats …

Ontology Of Geological Mapping, Tyler Boyd

Geosciences Theses

In this thesis, an ontology for the geological mapping domain is constructed using the Protégé ontology editor. The Geological Mapping ontology is developed using terms and relationships, and their properties, as they relate to creating a geologic map. This vocabulary is semantically modeled in the ontology using Web Ontology Language (OWL). The purpose of this thesis is to exemplify how an ontology can be designed and developed to represent geological knowledge as it relates to mapping.

The Use Of In Situ Gamma Radiation Measurements As A Method Of Determining Radon Potential In Urban Environments, Andrew S. Berens

Geosciences Theses

Radon is a radioactive gas that is the leading cause of lung cancer in non-smokers. While radon is natural and ubiquitous, higher concentrations greatly increase cancer risk. As such, understanding the spatial distribution of radon potential is key to planning and public health efforts. This project tests a method of determining radon potential using in situ measurements of gamma radiation. The in situ measurements were used to create a raster of gamma emissions in the study region using kriging. The resulting model showed that the operational scale of gamma radiation in the study region was 4.5 km. Indoor radon concentrations …

Authigenic Clays Used As Terrestrial Climate Proxies: Locality 80, Olduvai Gorge, Tanzania, Alexandra M. Simpson

Geosciences Theses

Authigenic clays are potential proxies for paleoclimate change when formed under saline conditions. Between 1.9 -1.7 mya, Olduvai was a closed-hydrologic basin into which Al- and Fe- rich detrital clays were transported from surrounding soils. Authigenic Mg-rich smectite formed within the basin due to chemical alteration in alkaline and saline conditions. 40 samples were chosen from a stratigraphic section in the center of the paleolake and analyzed to characterize the geochemical facies of the material using XRD, EMPA, and FTIR. ~70% of samples were Mg-rich with clay d060 XRD peaks between 1.506-1.523Å. EMPA indicated (Al₂O₃ + Fe …

Authigenic Clay Formation And Diagenetic Reactions, Lake Magadi, Kenya, Elena L. Nikonova

Geosciences Theses

The purpose of this study is to understand mineral diagenesis authigenic mineral and the effect of climate on mineral of Pleistocene-Holocene sediment deposits in the Southern Kenya Rift. Lake Magadi unique geologic settings are characterized by extreme alkalinity and high silica activities. The mineralogical analysis was achieved by X-Ray diffraction (XRD) and Scanning Electron Microscopy (SEM) applications. The bulk mineralogy (quartz, halite, calcite) is the same on all localities due to similar volcaniclastics compositions throughout the Kenya Rift Valley. The clay mineralogy significantly differ among the groups of sample localities. The differences reflect different tectonic settings and ambient climate regime. …

Interweaving Geochemical And Geospatial Data To Identify High Concentrations Of Metal Contamination From Copper, Lead, And Zinc Within Utoy Creek, Atlanta Ga, Ryan K. Walker

Geosciences Theses

Utilizing geochemical and geospatial data to explore the spatial variability of metals within streambed sediment of a local waterway may help to identify anthropogenic input of copper, lead, and zinc in urbanized streams. Utoy Creek is an urbanized stream located just southwest of downtown Atlanta. Baseline trace metal values and a reference site were used to determine if copper, lead, and zinc concentrations were higher or lower than baseline or reference site values. The Atlanta Metro Region (AMR) had over 2,100 miles of impaired streams listed on the 2008 303(d) list. This type of study can be used as a …