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267, Scott Brande

All 3D Rock Models

Model 267 - marble - metamorphic rock

SketchFab link: https://sketchfab.com/3d-models/267-5cd2ad41b91248f5926fcc7a3848fba8

266, Scott Brande

All 3D Rock Models

Model 266 - hornfels - metamorphic rock

SketchFab link: https://sketchfab.com/3d-models/266-b23a020c463f4f69ac3dd1ae659a2050

268, Scott Brande

All 3D Rock Models

Model 268 - phyllite - metamorphic rock

SketchFab link: https://sketchfab.com/3d-models/268-ba9597eb3c504ed5b91fe6ab00e24418

Investigating Antimicrobial Producing Bacteria Within The Soil, Adam Zwawi

A with Honors Projects

Genetic sequencing techniques used to identify soil antibiotic bacteria

Groundwater Vulnerability Assessment And Dye Trace Of War Fork River In Daniel Boone National Forest, Will Hemenover

Mahurin Honors College Capstone Experience/Thesis Projects

Daniel Boone National Forest plays a key role in preserving much of Kentucky’s karst regions, natural resources including timber, mineral deposits, and biodiversity, including over 300 species of concern. The health of these environments is determined by surface and groundwater streams in the forest, and karst systems are an integral environment where these systems are active. War Fork, a tributary to the Kentucky River in Jackson County, Kentucky, is a remote and understudied hydrologic system in the Daniel Boone National Forest that contains recreational and logging land uses. Due to karst areas being susceptible to contamination because of rapid water …

Permafrost Carbon: Progress On Understanding Stocks And Fluxes Across Northern Terrestrial Ecosystems, Claire C. Treat, Anna-Maria Virkkala, Eleanor Burke, Lori Bruhwiler, Abhishek Chatterjee, Joshua B. Fisher, Josh Hashemi, Frans-Jan W. Parmentier, Brendan M. Rogers, Sebastian Westermann, Jennifer D. Watts, Elena Blanc-Betes, Matthias Fuchs, Stefan Kruse, Avni Malhotra, Kimberley Miner, Jens Strauss, Amanda Armstrong, Howard E. Epstein, Bradley Gay, Mathias Goeckede, Aram Kalhori, Dan Kou, Charles E. Miller, Susan M. Natali, Youmi Oh, Sarah Shakil, Oliver Sonnentag, Ruth K. Varner, Scott Zolkos, Edward A.G. Schuur, Gustaf Hugelius

Biology, Chemistry, and Environmental Sciences Faculty Articles and Research

Significant progress in permafrost carbon science made over the past decades include the identification of vast permafrost carbon stocks, the development of new pan-Arctic permafrost maps, an increase in terrestrial measurement sites for CO₂ and methane fluxes, and important factors affecting carbon cycling, including vegetation changes, periods of soil freezing and thawing, wildfire, and other disturbance events. Process-based modeling studies now include key elements of permafrost carbon cycling and advances in statistical modeling and inverse modeling enhance understanding of permafrost region C budgets. By combining existing data syntheses and model outputs, the permafrost region is likely a wetland methane …

Soil Biogeochemistry In Riparian And Restored Tidal Wetlands: Monitoring And Method Evaluation, Joseph Anthony Loffredo

Open Access Master's Theses

Although soils are essential for sustaining ecosystems, they are often overlooked in routine monitoring efforts during restoration projects. This thesis tries to address the interest in and challenges of measuring and monitoring soil biogeochemical properties and processes to evaluate restoration trajectories. In the first part of this thesis (Chapter 1), I monitored tidal marsh vegetation and soil biogeochemical responses to restoration by thin-layer placement (TLP) of dredged sediments in a greenhouse mesocosm study and a parallel field study at an active restoration site in southern RI. In the greenhouse, aboveground plant biomass in mesocosms treated with +5 cm and +10 …

Recent Paleolimnological History Of Jackson Lake, Grand Teton National Park, Wyoming (Usa), Hillary Johnson

Theses and Dissertations--Earth and Environmental Sciences

This study utilizes a recently acquired, high-resolution CHIRP seismic reflection dataset and a deepwater sediment core to analyze the recent stratigraphy of Jackson Lake (Wyoming, USA). The western shoreline of Jackson Lake is situated adjacent to the Teton fault, a down-to-the-east normal fault that produces the spectacular high topography of Grand Teton National Park. The sediments of Jackson Lake are underexplored and consequently, their value as indicators of hydroclimatic and tectonic changes is unknown. Here, the sedimentary fill of Jackson Lake is explored as a natural archive of environmental change, specifically in reference to the influence of human outlet engineering …

Microstructural, Mineralogical, And Chemical Characterization Of The Handys Bend And Flax Creek Meteorites, Kentucky: Relevance For The Iron Meteorite Record, Ethan S.L. Davis

Theses and Dissertations--Earth and Environmental Sciences

Iron meteorites remain the only material view into planetary cores. Despite their scientific relevance, iron meteorites are relatively rare. In June 2021 and March 2022, the Kentucky Geological Survey received requests to identify two metallic specimens discovered in central Kentucky. The specimens were given the provisional names Handys Bend (3175.2 g) and Flax Creek (286.2 g). The goal of this project is to confirm meteoritic origin, characterize their structures and chemistry, assign genetic classifications, and examine potential relations to previous discoveries. Petrography was conducted using scanning electron microscopy. Mineral phases were examined using X-Ray diffraction crystallography. Chemical compositions were determined …

Thermal Alteration Of The Mineralogy Of Calcium Sulfoaluminate Cements: Implications For The Performance Of Rapid Repair Materials, Jillian Cavellier

Theses and Dissertations--Earth and Environmental Sciences

Calcium sulfoaluminate (CSA) was developed in part to lessen the environmental impact of cementitious materials compared to traditional Portland cements. CSA was first put into production in the 1970s and has been undergoing various performance testing to investigate its durability. Yet to be evaluated is CSA’s response to a rapid, high temperature event. In this study, X-ray diffraction, thermogravimetric analysis, Fourier transform infrared spectrometry and scanning electron microscope imaging were used to analyze alterations in the mineralogy due to such an event. As found in previous studies, after ~125°C, ettringite has been completely dehydrated. Ettringite decomposes into bassanite and calcium …

Assessing Microplastic Contamination Within Karst Groundwater Basins In Kentucky, Maaz Fareedi

Theses and Dissertations--Earth and Environmental Sciences

The input and abrasion of plastic waste in the environment has long been known to form microplastics (MPs). These ubiquitous contaminants are easily mobilized into hydrologic systems. MPs are now being found in karst aquifers around the world, including several across Kentucky, USA. Due to their size (< 5 mm in diameter), chemical properties, abundance, and wide distribution, MPs pose numerous ecological hazards, including uptake by organisms and as substrates for contaminant sorption. Karst groundwater is especially vulnerable to surface contaminants; however, knowledge of the extent of karst MP contamination is limited, with most studies focused on individual sites or small areas. In this study, we created a MP contamination dataset for 30 karst springs and 10 locations where cave sediments were characterized across Kentucky. MP concentrations in groundwater samples ranged from 0 to 41.1 items/L and yielded an average of 4.9 ± 8.7 items/L. Sediment MP concentrations ranged from 0 to 306 items/kg. We performed statistical analyses and linear regressions to examine whether groundwater MP concentrations could be explained by factors including land use, population density, basin area, numbers of sinkholes, and sinking streams. Our models revealed that population density, agrarian land use, sinking stream density, and basin area were related to MP concentrations. All factors except basin area trended positively with MP concentration, while basin area trended negatively. These relations are generally corroborated by existing literature, however they indicate that further studies with considerably larger sample sizes are needed to determine mechanistic relationships.

Visualizing And Automating Past, Real-Time, And Forecast Dynamic Hazard Maps For Shallow Colluvial Landslides In Eastern Kentucky, Nathaniel O'Leary

Theses and Dissertations--Earth and Environmental Sciences

Landslide hazards are a persistent threat to communities and infrastructure in Eastern Kentucky, where steep slopes, shallow colluvial soils, and variable hydrological conditions make slope failures frequent. This thesis presents an integrated approach to landslide hazard mapping (LHM) through the development of dynamic, spatiotemporal LHMs for shallow colluvial landslides. Two studies within this work investigate and refine the use of the Lu and Godt (2008) factor of safety (FS) equation to improve landslide predictions. The first study establishes a novel LHM workflow using Hydrus-1D to simulate soil moisture infiltration and fluctuations from precipitation and evapotranspiration (ET) data. This study also …

Sh-Wave Seismic-Reflection Efficiency Technique For Investigating The Wolf Island Fault, New Madrid Seismic Zone, Usa, Stephanie Vicroy

Theses and Dissertations--Earth and Environmental Sciences

The Reelfoot Fault within the New Madrid seismic zone has displacement at seismogenic depth to which the surface expression has unequal displacement. Previous work identified northeast-oriented transpressional fault strands northeast of a bend in the scarp as evidence for a through-going shear-zone, acting as potential accommodation for the observed strain imbalance. This investigation projected the trend of these faults to their intersection with an industry seismic survey at Wolf Island, Missouri, which exhibits a similarly structured faulted zone. We suggest this structure is the continuation of the through-going shear zone representing a previously unknown 22-km-long Quaternary-active fault that can affect …

Alteration Of Ultramafic Lamprophyres And Its Effect On Rare Earth Element Distribution In The Illinois-Ketucky Fluorspar District, Zachary O. Walton

Theses and Dissertations--Earth and Environmental Sciences

The ultramafic lamprophyres of the Illinois-Kentucky Fluorspar District (IKFD) have been identified as a potential domestic source of rare earth elements (REEs). The present distribution of the REEs and the role of the carbonate alteration in the distribution of the REEs is poorly understood. Petrographic and geochemical analyses were employed to determine the nature of the mantle source region and timing of the carbonate mineralization. Ratios of ¹⁴³Nd/¹⁴⁴Nd vs. ⁸⁷Sr/⁸⁶Sr demonstrate that in addition to the intrusion of primitive magma into the crust, a melt was generated from a mantle source region metasomatized by …

Re-Examination Of A Middle Mississippian Carbonate Mud-Mound Complex From The Fort Payne Formation In South-Central, Kentucky, Maxwell Mickelson

Theses and Dissertations--Earth and Environmental Sciences

This study examines the origin of a 213-m (700-ft) long, Middle Mississippian, carbonate “mud-mound complex” in the Fort Payne Formation of south-central Kentucky. The complex’s well-exposed, easily accessible, and well-preserved nature provides an opportunity to understand how mounds like this developed during a time of sediment starvation, basinward of the largely abandoned Borden-Grainger Delta complex.

The mound complex is formed of small, accretionary mounds that accreted onto the flanks of an eroded structural high and onto the backs of each other, apparently for protection from storms. Each sub-mound is composed of micrite-rich wackestone, comprising one of two biofacies: 1) alternating …

High Resolution Sedimentary Investigations Of Extant Lakes In North America, John Dilworth

Theses and Dissertations--Earth and Environmental Sciences

Investigation of past lake environments forms the discipline of paleolimnology. Paleolimnological studies seek to evaluate geophysical, geochemical, and ecological proxies and indicators contained within lake sediment archives. Using these potential stores of high-resolution environmental information, questions regarding climate, biological, and geochemical changes experienced by a lake and its watershed can be investigated. This dissertation research utilized lake sediment records from two lakes within North America to study different aspects of environmental change. This dissertation consists of three separate studies presented in three chapters.

Chapter Two presents a retrospective environmental assessment of Jackson Lake, Wyoming to investigate the impacts of dam …

Utilizing Isotope Tracing To Assess Land Use Implications To Tap And Stream Water Chemistry, Katrina Alexis Mcfadden

Theses and Dissertations--Biosystems and Agricultural Engineering

Water quality is an issue that continues to be worsened by extreme flooding, specifically in Eastern Kentucky. The most recent 2022 flooding event in Eastern Kentucky resulted in loss of human life, over $23.3 billion in damaged infrastructure, and impaired human health. Infrastructure failures, such as leaky pipes, are a growing challenge in these regions as rebuilding has occurred. Therefore, the goal of this project was to evaluate water quality in two of the counties most impacted by the 2022 flood in Kentucky, Breathitt and Perry Counties, using sulfur isotopes as a novel tracer to identify potentially failures in distribution …

Mining Contamination Of Legacy Deposits On Floodplains Along Turkey Creek, Western Border Of The Ozark Highlands, Hannah Riley Eades

Graduate Theses/Dissertations

Historical mining activities in the Tri State mining district in Southwest Missouri from 1850 to 1950 resulted in widespread metal contamination of stream sediments. Beginning in the 1840s, land disturbances associated with Euro-American settlement and agricultural expansion increased runoff and soil erosion rates resulting in the deposition of contaminated alluvium or legacy sediment on floodplains. This study assesses zinc (Zn) and lead (Pb) contaminated legacy deposits in cut-bank exposures along floodplains in Turkey Creek Watershed (119 km²) which drained mining areas in Missouri. Ore production histories were used date metal contamination profiles and calculate floodplain deposition rates in legacy deposits. …

Rapid Expansion Of The Limpkin Aramus Guarauna Across Anglo-America, A. Alam, R. Kaddoura, J. Jackson, R. Kannan

Journal of the Arkansas Academy of Science

We quantitatively document and describe the recent rapid expansion of the Limpkin Aramus guarauna across Anglo-America (United States and Canada). Using data downloaded from eBird (www.eBird.org), we present graphs showing the explosive growth in reports of number of individual birds and frequencies in checklists for this species in several parts of Anglo- America outside Florida (its traditional Anglo- American range). We also provide geographic progression maps to illustrate the expansion through time (2013-2023) and furnish qualitative information on foods consumed by the bird in new areas, based on a survey of 274 images uploaded by citizen scientists in eBird. Possible …

Geographical Variation In Songs Of Bachman’S Sparrow (Peucaea Aestivalis), L. Nguyen, K. Doñas, J. Jackson, R. Kannan

Journal of the Arkansas Academy of Science

We present an analysis of geographic variation in primary song components of the Near Threatened North American endemic, Bachman’s Sparrow (Peucaea aestivalis). These songs have 2 distinct portions: an introductory tweet we call the "whistle" and a more complex second portion that we call the "trill". We analyzed 327 songs from 111 recordings downloaded from eBird.org from the entire current range of the species. We grouped the recordings into 3 distinct geographic clusters, East, Central, and West. The data measured from spectrograms suggest a significant statistical difference among groups for 3 measured characteristics: frequency range of trill, number of horizontal …

A Review Of Herpetofaunal Distributions In Arkansas With Special Emphasis On Contributions From Citizen Science: Part I – Snakes, R. Jacobs, N. Ortiz, J. Jackson, J.D. Willson, K.G. Roberts, R. Kannan

Journal of the Arkansas Academy of Science

We present a comprehensive updated review of the distributions of the 38 species of snakes in Arkansas. We compare historical and current distributions with citizen science data uploaded and verified in iNaturalist, a leading biodiversity monitoring online citizen science database. The Arkansas Herpetological Atlas, a website maintaining species occurrence records, is also used and compared. We highlight the role played by iNaturalist in enhancing our knowledge of snake distributions in Arkansas. 10,885 verified and vetted Research Grade (RG) observations of Arkansas snakes have been recorded in iNaturalist, expanding the known distributions of 36 of the 38 species. This is the …

Energy Content Of Acorns Of Shinnery Oak (Quercus Havardii) In The Diet Of Scaled Quail (Callipepla Squamata) In Southeastern New Mexico, J.L. Hunt, M.E. Grilliot, T.L. Best, D. Lozano-Lopez, E.R. Neilson, I.C. Castillo

Journal of the Arkansas Academy of Science

Shinnery oak (Quercus havardii) is a deciduous, low-growing shrubby tree that is a dominant plant in large areas of grassland in western Oklahoma, the Texas Panhandle, and eastern New Mexico. Acorns of the plant are important food items for many wildlife species, including scaled quail (Callipepla squamata), mourning doves (Zenaida macroura), and endangered lesser prairie-chickens (Tympanuchus pallidicinctus). We analyzed the energy content of acorns of shinnery oak obtained from the crops of scaled quail collected from plains-mesa sand-scrub in Lea and Eddy counties, New Mexico. Acorns were removed from crops and dried for 48 hours at 60°C to remove moisture …

Towards Machine Learning-Based Control Of Autonomous Vehicles In Solar Panel Cleaning Systems, Farima Hajiahmadi

Theses and Dissertations

This thesis presents a machine learning (ML)-based approach for the intelligent control of Autonomous Vehicles (AVs) utilized in solar panel cleaning systems, aiming to mitigate challenges arising from uncertainties, disturbances, and dynamic environments. Solar panels, predominantly situated in dedicated lands for solar energy production (e.g., agricultural solar farms), are susceptible to dust and debris accumulation, leading to diminished energy absorption. Instead of labor-intensive manual cleaning, robotic cleaners offer a viable solution. AVs equipped to transport and precisely position these cleaning robots are indispensable for efficient navigation among solar panel arrays. However, environmental obstacles (e.g., rough terrain), variations in solar panel …

Determining Hydraulic Characteristics In Close Proximity Of Hymenocallis Coronaria Within The Flint River Basin, Georgia, Sarah K. Tash

Theses and Dissertations

Emergent macrophytes in river systems occupy a narrow habitat for optimal survival. Each plant species adapts to a set of conditions that meets the physiological requirements to grow and reproduce. The influence of hydraulic characteristics on plant morphology is significant within fluvial systems. Macrophytes must be able to withstand swift flowing water and changes in water surface levels in order to compete with other plant species for limited habitat availability. In addition, emergent macrophytes require water levels to be low enough to allow the reproductive portion of plants to remain above water during certain times of the year. Hymenocallis coronaria …

Water Column Controls On Magnetic Mineral Formation And Preservation, Josephine Benson

Dartmouth College Master’s Theses

Iron-bearing minerals in the sedimentary record are frequently used to reconstruct past depositional environments. This is accomplished through geochemical, magnetic, and mineralogical analyses placed in geological context. These interpretations, however, depend on our understanding of how iron minerals form in nature. To better understand the formation of magnetic iron minerals in redox-stratified depositional settings, the study of modern analogs is crucial to unraveling environmental context no longer available from geological deposits. In this study, I utilized four anoxic and sulfidic stratified lakes within a 100-mile radius to examine the effects of small variations in lake properties on magnetic mineral formation …

Assessing Plastic Pollution On Shorelines And In Coastal Sediments, Victoria Madison Fulfer

Open Access Dissertations

Plastics have become pollutants around the world, entering the marine environment predominantly from many land-based sources. A small proportion of plastics in the marine environment also come from sea-based activities such as fishing, boating, and shipping. Once in the environment, the low density of most plastic polymers allows transport around the globe by winds, rivers, currents, waves, floodwaters, and tides. As a result, the ultimate fate of present and past plastic pollution is poorly constrained; however, much material in the sea is thought to accumulate in marine sediment over time.

Plastics in the environment have a wide range of morphologies …

Sea Level Rise Driven Groundwater Inundation: Effects Of Island Hydrogeology On Freshwater Lens Dynamics, Lauren K. Mancewicz

Dissertations, Master's Theses and Master's Reports

Groundwater inundation due to sea level rise poses a threat to fresh groundwater availability in coastal areas, and small islands are particularly vulnerable. On an island, when sea level rises, the freshwater lens also rises due to the difference in density between the salt and fresh groundwater. As the water table rises above the land surface it forms a lake and the water is exposed to additional evaporative losses, reducing the amount of fresh water available. This work aims to improve our understanding of groundwater inundation due to sea level rise and the impact of different hydrogeologic settings and phenomena …

Anomaly Mapping Of Heavy And Light Rare Earth Elements In Central Upper Peninsula Of Michigan Using Geostatistics And Fractal Analysis, Sunday Joseph

Dissertations, Master's Theses and Master's Reports

Rare earth elements (REEs) have gained significant global importance due to their critical role in supporting the transition towards reduced carbon emissions through industrial applications. REEs serve as essential raw materials for various critical components in modern infrastructure, defense systems, and technological advancements. Geochemical and geophysical data are pivotal in assessing the potential of REEs. Geochemical data provide direct insights into the elemental composition of rocks and soils, offering valuable information on the potential presence and dispersion of REEs. However, the complex geological processes that influence the distribution of REEs often exhibit intricate spatial patterns that may not be fully …

Response Of Open Volcanic Systems To Static Stress Changes, Aimee Zimmerman

Dissertations, Master's Theses and Master's Reports

Large earthquakes of magnitude 7.0 or greater can alter volcanic emissions and even trigger eruptions at nearby volcanoes. The stress changes imparted by large earthquakes can cause otherwise stable conditions within the magmatic system to be disturbed, potentially inducing volcanic activity. The extent of the triggering potential is still unknown due to insufficient understanding of the mechanisms involved. We model static stress changes for 174 earthquake-volcano pairs from 2000-2023 at volcanoes within 500 km, computing changes in both the normal stress perpendicular to the direction of horizontal maximum stress and dilatational strain. We then use thermal satellite data to measure …

Leveraging Uncertainty To Understand The Causes And Consequences Of Observed Climate Change, Alexander Reid Gottlieb

Dartmouth College Ph.D Dissertations

Detecting and attributing climate change to date is essential to understanding the harm global warming has caused and the threat it poses in the future. Yet detecting and attributing historical climate change and its attendant impacts is challenging owing to observational uncertainties in the historical record, the difficulty of isolating the forced response from unforced variability, and the methodological ambiguity on how to best map climate variability and change onto climate impacts. In this thesis, I use the study system of Northern Hemisphere snow to demonstrate how synthesizing a wide array of observational and climate model data with methods from …