Earth Sciences Commons^™

Assessing The Relationship Between Subsurface Geology And Surficial Geomorphology: Remotely Predicting Geologic Features And Geohazards Using An Elevation-Trained Machine Learning Algorithm In The Northern Gulf Of Mexico, Allison L. Wing

Theses and Dissertations

This thesis evaluates the capacity to predict subsurface geologic features and submarine landslide susceptibility using surficial geomorphology derived from bathymetric elevation data in the Northern Gulf of Mexico. Quantitative geomorphic variables including slope, curvature, aspect, rugosity, geomorphons, and Bathymetric Position Index were generated from 30-meter digital elevation models and used as explanatory variables in presence-only Maximum Entropy models. Known locations of faults, pockmarks, mud volcanoes, hydrocarbon seeps, and landslides (particularly intact scarps) were used to train and validate predictive models through k-fold cross validation. Model performance was assessed using omission rates and AUC values. Results demonstrate that specific geomorphic signatures, …

Using Seafloor Geomorphology, Classification Schema, And Spatial Analysis To Predict Geologic Structures, With Applications For Mars, Emma Morgan

Theses and Dissertations

This study evaluated whether seafloor geomorphology can be used to predict subsurface fault locations along the Cascadia continental margin and explored whether such relationships can be transferred to Mars. Geomorphological classification schemas such as geomorphons, bathymetric position index (BPI), slope, rugosity, aspect, and curvature were derived from seafloor bathymetry data and used as predictor variables in maximum entropy (MaxEnt) models developed separately for Pre-Pleistocene, Pleistocene, Quaternary, and active fault datasets. Model performance ranged from AUC = 0.62 to 0.67, showing moderate predictive skill, with younger fault systems exhibiting stronger geomorphic associations. A secondary analysis showed a weaker but detectable relationship …

Evaluating The Spatial Relationship Between Geomorphology And Subsurface Structures On The Us Atlantic Margin With Applications To Other Terrestrial Planets, Andrea Caitlyn Stiles

Theses and Dissertations

High-resolution digital elevation models (DEMs) are widely available for terrestrial planetary bodies, but subsurface structural data remain limited. This research evaluated whether surface geomorphology could predict subsurface features, specifically faults and methane seeps, along the US Atlantic continental margin as an analog site. Faults were mapped with seismic interpretation and compared with quantitative geomorphic classifications derived from 100-m bathymetry including slope, aspect, rugosity, bathymetric position index, and geomorphon classes. Maximum-entropy modelling was used to predict fault occurrences from surface data. Results indicated that specific geomorphic landforms and slopes had the strongest control on fault presence, reflected in topographic expression of …

Morphological Evolution And Sediment Budget Of A Flood-Tidal Delta On The Rio Grande Delta Plain: Bahia Grande, Texas, Usa, Aleen Pertuz Paz

Theses and Dissertations

The Isabel Delta is a recently formed flood-tidal delta within the restored Bahia Grande system on the Rio Grande Delta Plain, Texas, USA, where renewed tidal connectivity has created conditions for rapid sediment buildup and landform evolution. This study quantified morphological changes from 2008 to 2025 using satellite imagery. It assessed sediment retention by comparing the effective sediment discharge required to reproduce observed delta growth with field-based estimates of sediment supply derived from channel hydrodynamics, cross-sectional area, and suspended sediment concentration. The delta expanded steadily throughout the study period, with increases in bar, channel, and total surface area, and an …

The Effects Of Overwash On Barrier Island Evolution And Building A Barrier Island Measure Of Resistance, Beth Thomas

Theses and Dissertations

Barrier islands are critical for coastal communities, as they serve as a natural buffer against storm surge, waves, and the effects of rising sea levels, protecting life and property. These islands continuously evolve due to both normal and severe environmental conditions; global warming makes it increasingly difficult to predict the evolution of these islands due to increases in storm frequency and intensity. We present a cellular model of barrier island evolution consisting of biotic and abiotic processes including the effects of vegetation, wind, ocean currents, and gravity. The model is used to predict the future evolution of barrier islands off …

High-Resolution Mapping Of Soil Moisture Variation Using Uas Thermal And Multispectral Imagery, Jackline Amma Timah

Theses and Dissertations

In agricultural landscapes, soil moisture regulates hydrologic partitioning, nutrient transport and water quality, land-atmosphere energy exchange that shapes local climate, and ecosystem resilience. However, traditional monitoring approaches, such as in-situ sensors and satellite imagery, often lack the spatial resolution required to capture fine-scale soil moisture variability. This study evaluated whether unmanned aerial system (UAS)-derived thermal, multispectral, and terrain variables can capture fine-scale spatial variability in volumetric water content (VWC) within an SRB in central Illinois.

High-resolution imagery was collected and paired with 50 field-measured VWC observations. Land surface temperature (LST), vegetation indices (NDVI and NDRE), spectral bands, and slope were …

Characterizing A Low-Gradient Stream In Central Illinois As Gaining Or Losing And Observing Seasonal Changes In This Behavior, Eric Timothy Brunner

Theses and Dissertations

While the seasonal behaviors of low-gradient streams have been studied, the behavior of surface water and groundwater interactions within low-gradient streams in glaciated terrain is not fully understood. A third order, low-gradient glacial stream with a saturated riparian buffer in central Illinois was studied to determine the direction of flow between the surface water and groundwater. The goals of this study were to determine 1) whether the stream was gaining or losing water, and 2) whether the gaining or losing nature of the stream-aquifer system changes seasonally. At both an upgradient and downgradient location, two wells were installed: one in …

Assessing Glacial Mass Change And Its Impact On Water Resources In Parts Of The Himalayas Using Satellite Remote Sensing, Kriti Panta

Theses and Dissertations

This study investigates long-term changes in terrestrial water storage and their impact on hydrological processes in glacier-fed regions of Nepal. The study focuses on the central to eastern Himalayan region, including major river basins within the Koshi system. Multiple datasets, including the Gravity Recovery and Climate Experiment (GRACE) and GRACE follow-on (GRACE-FO) missions satellite data, the Global Land Data Assimilation System (GLDAS) products, and in situ streamflow data, were used for the period 2002–2019. Terrestrial Water Storage Anomaly (TWSA) derived from GRACE data shows a strong decreasing trend over time, indicating significant water storage loss across the study area. Soil …

Modeling The Impact Of Projected Water Demand On Groundwater Flow And Transport In The Mahomet Aquifer, Christabel Chinonye Abugu

Theses and Dissertations

The Mahomet Aquifer is a vital groundwater resource in east-central Illinois, supporting municipal, agricultural, and industrial water use. With projected changes in water demand driven by population growth and future socioeconomic conditions, assessing the long-term response of the aquifer is critical for sustainable groundwater management. Increased pumping to meet future demand may contribute to groundwater-level decline, intensified cones of depression, and altered groundwater-flow paths relevant to contaminant migration. This study addressed two research questions: (1) how projected changes in groundwater demand affect groundwater levels in the Mahomet Aquifer, and (2) how projected demand influences groundwater-flow paths relevant to contaminant migration. …

Does The Powder River Pass Shear Zone Exist? Geologic Map And Geochronology Of The Bighorn Mountains Caribou Creek 7.5-Minute Quadrangle, Lula G. Staley

Theses and Dissertations

This study produced a 1:24000-scale geologic map of the Caribou Creek 7.5-minute quadrangle in the Bighorn Mountains, Wyoming, by integrating field observation and U-Pb zircon age data. The results of this study will contribute to the USGS EDMAP program by subdividing the southern gneiss terrain. The quadrangle occurs almost entirely in the Bighorn National Forest and is in the drainage of Clear and Crazy Woman creeks. Elevations range from 6,800-9,400 ft. The quadrangle is dominated by Archean crystalline rocks of the Wyoming Province Beartooth-Bighorn Magmatic terrane, mainly granodiorite and tonalite gneiss with lesser migmatite. Several orientations and ages of mafic …

Investigating Phosphorus Load Trends And Driving Factors In Illinois Watersheds Using Machine Learning Algorithms, Hannah Lartey

Theses and Dissertations

Phosphorus (P) pollution in Illinois watersheds has become a significant water quality concern. Recent studies have shown increasing concentrations in streams and rivers, leading to eutrophication, which damages aquatic ecosystems and threatens human health. This study examines temporal trends in total phosphorus loads across 79 monitoring stations in Illinois from 1979 to 2020 and identifies the main environmental factors that influence P load variability. Trend analyses were conducted using the nonparametric Mann-Kendall and Sen’s slope methods. GIS-based climate, hydrology, and soil property datasets were assembled for each monitoring station. These datasets were used to build machine learning models using the …

Mississippi River Pre-Loess Terrace Deposits: Distribution Of Aggregate Resources, Jonathan Leard

Theses and Dissertations

Pre-loess Terrace Deposits are a Pleistocene, high-quality aggregate resource of gravel, sand, and clay subjacent to loess of varying thickness along the eastern valley wall of the Yazoo Basin in Mississippi. This project delineated 1,230 mi2 of this resource with a volume greater than 33 billion yd3 from the misinterpreted Citronelle Formation in Desoto, Tate, Marshall, Panola, Tallahatchie, Yalobusha, Grenada, Carroll, Holmes, Yazoo, Madison, Hinds, Warren, Jefferson, Claiborne, Adams, Franklin, and Wilkinson Counties with nine terrace base levels at 40, 180, 220, 250, 270, 300, 330, 340, and 370 feet msl indicated by test holes, gravel mine data, outcrop studies, …

Long-Term Sedimentation Rates And Patterns Of Alluvial Ridge Basins (Esteros) Of The Rio Grande Delta (Tx, United States Of America), Kynan Joseph Rutan

Theses and Dissertations

Little is known about the century-scale sedimentation rates and patterns of Alluvial Ridge basins within river deltas, especially in the Rio Grande Delta (RGD). To better constrain this, 22 cores were collected in the Bahia Grande Complex (BGC) and analyzed for grain size, organic content, age dates, and elemental composition.

Results show that grain size and sedimentation rates decrease from an artificial inlet to the basin interior, with elevated sedimentation in the south. Also, human activities, such as the construction of the Brownsville shipping channel in the 1930s, altered sedimentation dynamics in the basin by blocking natural inlets and leading …

Modern Water And Sediment Transport Patterns In Alluvial Ridge Basins Of The Rio Grande Delta, South Texas, Usa, Waqid Nabi

Theses and Dissertations

Alluvial ridge (AR) basins are shallow, marine-influenced depressions within river deltas, yet their flow and sediment dynamics remain poorly understood. This study examines hydrodynamics and sediment transport patterns in the Bahia Grande Complex, which are AR basins of the Rio Grande Delta, using tilt current meters, water-level and turbidity loggers, and suspended and bed-sediment sampling. The AR basins function as wind-dominated, microtidal environments, where pre-existing basin geometry and hydrodynamic forcings control water flow and sediment distribution patterns. Seasonal wind patterns and storms modulate water levels and flow connectivity. Substrate patterns reflect frequent resuspension in the shallow northern basin, maintaining coarse …

Hindcasting The Occurrence Time Of Major Earthquakes Using Machine Learning And Time Series Analysis, Rubidha Devi D

Theses and Dissertations

An earthquake is an intense shaking of the ground that typically occurs when tectonic plates move beneath the surface of the Earth. Scientists analyze historical seismic records and geophysical and atmospheric signs to build models estimating the probability of major earthquakes by detecting patterns and anomalies in data such as ground deformation and seismic waves. This study would help in predicting earthquakes to minimize risks of people and buildings.

The present study investigates the devastating earthquakes along the Chilean subduction zone in South America, linking non-seismic data to machine learning predictions of Outgoing Longwave Radiation (OLR) and Relative Humidity (RH) …

Soil Ethics In Practice: Harvesting Conservation Choices Among Puerto Rican Coffee Farmers, Patricia Marie Cordero-Irizarry

Theses and Dissertations

Coffee farming in Puerto Rico has declined over recent decades, partly due to deteriorating soil quality. However, the decision-making process behind farmers’ adoption of soil conservation practices remains unclear, particularly the overlooked role of soil ethics, which emphasizes the moral principles guiding human relationships with the soil. This mixed-methods study examined coffee farmers’ adoption of soil conservation practices by integrating the Values-Beliefs-Norms (VBN) theory and a newly developed Soil Ethics Survey (SES) instrument for the quantitative component, while using Decision-Making Theory and Social Cognitive Theory to qualitatively explore how farmers’ experiences and reflections shape their soil ethics. Quantitative findings revealed …

Study Of Anomalous Variations In Seismic And Non-Seismic Parameters Using Machine Learning Techniques To Develop The Earthquake Forecasting Model In The Himalayan Belt, Senthil Kumar M

Theses and Dissertations

Understanding and forecasting earthquakes is not just about science it’s about saving lives, even as the dynamic and hidden nature of Earth's tectonic processes makes this an intricate challenge. The Himalayan belt is one of the most seismically active regions globally due to the collision of the Indian and Eurasian tectonic plates. Investigating this region is essential for understanding highly complicated tectonic mechanisms and reducing substantial hazards posed to millions of people by persistent and intense seismic events. This study aims to enhance forecasting methodologies by applying machine learning techniques while dealing with the inherent challenges of geological complexity and …

First Detrital Zircon Provenance Data From Oligocene-Pleistocene Sediment In The Beaufort-Mackenzie Basin, Arctic Ocean, Joseph Martina

Theses and Dissertations

Sediment, runoff, and nutrient input to the Arctic Ocean plays a critical role in both physical and biological processes that impact regional and global systems. The Beaufort-Mackenzie Basin, situated in the Arctic Ocean offshore northwestern Canada, contains more than 14 km of clastic strata and provides a record of erosion and sediment transport from the Cretaceous to present. Pliocene sedimentation rates within the basin jump nearly 2000% relative to underlying units, but the cause of this shift remains unknown. We used cuttings from the N. Issungnak L-86 well, focusing on the Oligocene-lower Miocene Kugmallit and Mackenzie Bay sequences and the …

Mo Isotopes In The Aleutian And Costa Rican Arcs: Source Variability And Juvenile Crust Formation, Ekaterina Rojas Kolomiets

Theses and Dissertations

Chemical and physical transfer between the surface, lithosphere and asthenosphere at subduction zones leads to arc magmatism and continental crust (CC) production. Subduction zones magmas and associated volcanic products sample a variety of magmatic sources that contribute to their chemical compositions in various proportions. This dissertation contributes to the study of subduction zones magmatism by assessing the relative role of subduction inputs (sediments, altered oceanic crust – AOC – and serpentinite) as flux agents in the arc magmatism and in CC formation in subduction zones under the scope of Mo isotope systematics.

I present the first Mo isotope analyses form …

Calculating Moment Magnitude Using The Coda Calibration Technique To Update The Earthquake Catalog Of Iraq (1900-2021), Muntadher Al-Kaabi

Theses and Dissertations

The first comprehensive earthquake catalog for Iraq based on moment magnitude (Mw) ‎was compiled by Onur et al. (2017). It spanned the period from 1900 until the end of ‎‎2009, covered the region between 26°–40° N latitudes and 36°–51° E longitudes, and ‎included more than 18,000 earthquakes, of which roughly 4,000 are of Mw 4.0 or larger. ‎With the ongoing efforts of updating the probabilistic seismic hazard assessment ‎‎(PSHA) and the Iraqi building code, the need for an updated earthquake catalog for Iraq ‎in terms of moment magnitude (Mw) has been raised. Robust estimation of moment ‎magnitude (Mw) can be …

Assessment Of Water Quality And Remediation Of Heavy Metals In A Coastal System, Christiana Fumnanya Eziashi

Theses and Dissertations

This research focuses on a three-part study to assess water quality in a coastal system and evaluate the absorption capacity of modified biochar and algae to remediate cadmium (Cd). The first chapter introduces the hypothesis and objectives, and the second chapter provides a detailed literature review. The third chapter focuses on the first study, where surface water samples and water quality data collected from a manned boat and a novel autonomous surface vessel (ASV) in the Western Mississippi Sound (WMS) in the summer of 2021 and 2022 were analyzed and the interrelationship between the nutrient, trace metals, salinity, and chlorophyll-a …

Apatite Entrapment Of Iodine For Nuclear Waste Disposal Applications, William E. Laird

Theses and Dissertations

The purpose of this thesis is to provide baseline knowledge of iodine incorporation into calcium phosphate minerals, specifically apatite. Iodine-129 is a fission product in Spent Nuclear Fuel (SNF) that can administer significant amounts of radiation in small quantities. Apatite (Ca10(PO4)6 (OH, F, Cl)) has been studied for the use of radionuclide confinement. Experimental design was set up to mimic temperatures expected in geologic repositories from 40 to 250℃. Experiments are broken into 2 groups based on iodine species being examined. The first group focuses on iodate (IO3-) which is prevalent under oxidized conditions, and the second handles iodide (I-) …

Earth Analogue Analysis Of Volcanic/Tectonic Interactions With Applications To Venusian Stresses, Michael Ortigoza

Theses and Dissertations

Venus shares many geological similarities with Earth, yet its tectonic processes and magma injection mechanisms remain poorly understood. A key question in planetary geology is how effusive volcanism persists despite the intense horizontal compression terrestrial bodies experience over time. To explore these issues, we examine the Spanish Peaks dike swarm in Colorado which serves as an ideal site for investigating magma intrusion under compressive stress conditions. Through field mapping, orientation measurements, and structural analysis, we identify a strong relationship between pre-existing joints and dike orientations, suggesting that these fractures serve as critical magma pathways in compressive regimes. Additionally, evidence of …

The Effect Of Hiv-1 Infection Associated Bacterial Lipopolysaccharide (Lps) On Human Oral Keratinocytes: Implications For Promoting Chronic Inflammation, Md Shafayat Jamil

Theses and Dissertations

Human immunodeficiency virus type 1 (HIV-1) remains a major global health concern, affecting approximately 39 million people worldwide, with 500,000 new infections reported in 2022. While combined antiretroviral therapy (cART) has significantly reduced viral replication, HIV-1 infection is linked to various comorbidities, including oral dysbiosis and accelerated aging. Immune dysregulation in HIV-1–infected individuals promotes the proliferation of pathogenic gram-negative bacteria like Porphyromonas gingivalis, a key contributor to periodontal disease. P. gingivalis secretes lipopolysaccharide (LPS), which adversely affects human oral keratinocytes (HOK), the first line of defense against microbial threats in the oral cavity. HOK recognize LPS as a threat, …

Spatio-Temporal Pattern Of Nutrient Dynamics In The South Texas Coastal Watershed, Mohammad Sadman Alam

Theses and Dissertations

Eutrophication threatens aquatic ecosystems by altering productivity through excessive nutrient inputs. In some systems, primary productivity is limited by nitrogen (N), phosphorus (P), or both, based on the N:P ratio defined by the "Redfield" ratio. South Texas, facing rapid urban growth and industrialization, is at risk of higher nutrient loads, but research on nutrient dynamics in this region is limited. This study investigates nutrient variations in the freshwater (FW) abandoned distributaries of the Rio Grande and hypersaline saltwater (SW) systems. Results showed a significant decrease in dissolved inorganic nitrogen (DIN) and an increase in dissolved inorganic phosphorus (DIP), shifting the …

Mitigation Of Droughts And Floods From Conjunctive Water Resource Management Using Managed Aquifer Recharge (Mar): Experiments And Numerical Modeling, Sumiaya Amin Preota

Theses and Dissertations

Water supply of Rio Grande Valley in South Texas has been impacted by intensified climate extremes such as droughts and floods. This research assessed the viability of conjunctive water resource management using Managed Aquifer Recharge (MAR) carbon-modified infiltration basins. Multiple environmental variables in the Arroyo Colorado watershed were investigated, i.e., (i) water availability- quantity of floodwater can be repurposed, (ii) storativity and suitability - capacity within the unsaturated aquifer and ideal locations for building infiltration basins, (iii) water quality- contaminant removal using active carbon/biochar.

Unappropriated flow and high magnitude flow (HMF) analysis indicated that excess floodwater can be a …

Climate Change And The Field Of Farm Labor In The Lower Rio Grande Valley, Texas, Cody Richard Mortell

Theses and Dissertations

Farm workers in the United States are often vulnerable to adverse impacts of climate change, particularly extreme heat. This study explores farm workers’ climate change perceptions (CCP) as a mediating force in climate adaptation. Using latent class analysis, in-person survey data (n=404) from Lower Rio Grande Valley, TX (2024) and NOAA data were analyzed. Results were interpreted using Bourdieu’s field analysis framework and his notions of capital and symbolic power. Findings include: a social hierarchy with three latent classes of workers based on economic, cultural, social, and symbolic capital, which statistically significantly affected CCP. Workers in higher structural positions were …

Integrated Coastal Science And Dune Management: A South Carolina Perspective, Michelle Harris

Theses and Dissertations

Historically, coastal dunes have been poorly understood from a societal perspective despite their protective role in attenuating incoming waves to reduce onshore flood risk. As developed coastlines promote strategies to design and maintain managed dune systems, it is necessary to ensure these strategies are optimized for dune health and resilience, particularly given the increasing threat of natural and anthropogenic stressors. This dissertation work aims to identify strategies that influence coastal dune management in South Carolina (SC), USA from an integrated approach, including a current use assessment, a mesoscale field-based study on strategy efficacy, and by incorporating a societal assessment and …

Extracting Metamorphic Histories Utilizing U-Pb Laser Ablation Zircon Geochronology From The Southern Appalachians Crystalline Rocks And Detrital Sediment, Meredith Kay Love Gawai

Theses and Dissertations

The southern Appalachian mountain belt is an accretionary orogen that formed in the southeastern United States through several phases of oceanic subduction and continental collision during the Paleozoic Era and culminated in the formation of the supercontinent Pangaea. Although many U-Pb zircon ages have been collected from the igneous, metaigneous and metasedimentary rocks in the crystalline core of the southern Appalachians, there remain opportunities to better reconstruct the metamorphic and magmatic history of the southern Appalachians through the lens of zircon geochronology. Such data are valuable in identifying genetic relationships between candidate terranes of the orogen. Herein, I present laser-ablation …

Geospatial Machine Learning Approaches For Studying Urbanization Impact, Surface Reflectance Patterns, And Groundwater Health Risks, Bibhash Nath

Theses and Dissertations

Geospatial machine learning techniques have been used to study: the impact of urbanization on land use and land cover change, surface reflectance patterns in boreal regions, and groundwater health risks from arsenic in India. These studies combined spatial data, remote sensing, and predictive models to gain valuable insights for sustainable living and protecting human health.