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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, …

The Effects Of Nanobubble Fertigation And Soil Conditioners To Improve Nutrient Dynamics, Soil Microbial Activity, And Chili Productivity, Betty Natalie Fitriatin, Euis Ahah Rokayah, Elsa Naila Elmyra, Tualar Simarmata, Nicky Oktav Fauziah, Hanif Fakhrurroja

Jurnal Kultivasi

Drip fertigation is a fertilization method that integrates nutrient delivery with an irrigation system, which is capable of optimizing the direct delivery of nutrients to the root zone. This experiment aims to investigate the effect of drip fertigation with nanobubble technology, and soil conditioners on the population of Phosphate-Solubilizing Bacteria (PSB) and Azotobacter spp., available phosphorus, total nitrogen, growth, and yield of red chili. The study used a Strip Plot Design with two factors and three replications. The first factor was nutrient application (solid NPK fertilizing as control; drip fertigation; and drip fertigation with nanobubble technology), and the second factor …

Measurements Of Water-Film Thickness On Cave Walls And Speleothems, Alexandre Honiat, Salaheddine Skali-Lami, François Bourges, Bruno Lartiges

International Journal of Speleology

The water-film that coats cave walls and speleothems is a key player for the regulation of cave microclimate and the control of speleothem growth. In this paper, we demonstrate the capability of a confocal optical sensor to quantitatively measure on-site the rapid variations of water-film thickness when dripping, active condensation, or dryness occur on walls of various caves. Results obtained from a sample of four prehistoric caves and one stalagmite cave from Southwest France, indicate that the measurable thickness of water-films is generally in the 25-70 µm range for cave walls and reaches 200-300 µm on the horizontal plane of …

A Sedimentary Source Of Rare Earth Elements In The North Atlantic, Rylee D. Lindner

Electronic Theses and Dissertations

Individually and as a series, the Rare Earth Elements (REEs) are powerful geochemical tracers of environmental processes. However, ambiguities in the oceanic budgets of the REEs hamper their application. Growing evidence suggests a sedimentary benthic flux via the pore water is the major source of REEs to the ocean, with extrapolated estimates of this flux being equivalent in magnitude to that “missing” from modern budgets. However, existing pore water REE data are available from only a few locations globally with no representative dataset from the open North Atlantic. This data scarcity limits our ability to constrain flux estimates and understand …

Collaborative Research: Evolution Of The Tristan-Gough-Walvis Ridge Hotspot System: Age And Composition Of Expedition 391/397t Volcanic Basement, Katherine Elizabeth Potter

Funded Research Records

No abstract provided.

Collaborative Research: Rapid: Fault Rupture And Spring Sampling Of The 2023 Kahramanmaras, Turkey, Earthquake Sequence Ruptures, Alexis Ault, Dennis Lowell Newell

Funded Research Records

No abstract provided.

Stream Behavior Characterization Of Marin County Coastal Watersheds And Their Influence On Salmonid Habitat, Ellie L. Murdoch

Master's Theses

Coastal watersheds in California are increasingly affected by climatic variability, threatening stream behavior, ecological function, and salmonid habitat suitability. This study evaluated streamflow behavior of seven watersheds in Marin County, California, with detailed analysis of Corte Madera, Olema, and Redwood watersheds, which are not influenced by reservoir releases. Using USGS stream gauge records, PRISM climate data, SSURGO soils, and geologic and vegetation information, streamflow metrics critical to salmonid life cycles were quantified for water years 2014 to 2023. Watersheds with greater storage capacity, such as Redwood, exhibited muted hydrologic responses, including delayed flow activation, lower peak flows, slower recession rates, …

A Study Of The Stratigraphic And Petrological Characteristics Of Section (10,323-10,325 Ft), Prevost 1- 11, Bay County, Michigan, Hajir Al Harthi

Honors Theses

This study presents a detailed petrological characterization of a short core section (10,323-10,325 ft) from the Prevost 1-11, Bay County, Michigan. This work is part of a broader carbon capture, utilization, and storage (CCUS) project to determine whether the Glenwood Formation could be an effective confining unit (CU) for carbon dioxide (CO2) injection in the underlying St. Peter Sandstone. The methods used to collect petrological data include standard core description, Xray fluorescence spectroscopy (XRF), powder X-ray diffraction (XRD), thin section microscopy, and scanning electron microscopy (SEM) including backscattered electron (BSE), energydispersive X-ray spectroscopy (EDS), and secondary electron (SE) modes. These …

Pymelt-Px: A Python Script For Modeling Melting Of A Pyroxenite-Peridotite Bilithological Mantle, Ana L. Jimenez Bustos

Department of Earth and Atmospheric Sciences: Dissertations, Theses, and Student Research

The study of oceanic crust formation is a fundamental building block in our understanding of the processes of planetary formation, necessitating an understanding of the melt generation processes that help form oceanic crust. To aid in this purpose, we present pyMeltPX: a bilithological pyroxenite-peridotite mantle modeling script. Although the mantle is primarily comprised of peridotite, pyroxenite is a minor but ubiquitous feature of the mantle and can contribute a disproportionate amount of melt to crustal generation in mid-ocean ridge and ocean island basalt settings. Our model, pyMeltPX, is a python coded, extensible tool based on the Excel calculator by Lambart …

The Depositional Environment Of The Triassic Cow Branch Formation, Dan River Basin Of Virginia And North Carolina Through Petrographic Study And Geochemical Analysis, And In Relation To Taphonomic Processes And Vertebrate Morphology, Gina M. Workman

All Graduate Reports and Creative Projects, Fall 2023 to Present

The Upper Triassic Cow Branch Formation of the Dan River Basin, located in southern Virginia and northern North Carolina, has long captivated generations of geoscientists. Since the 1970s, researchers have sought to unravel the mystery surrounding the depositional environment of this ancient lake system. This world-class lagerstätte hosts a diverse assemblage of fossil fauna and flora, with a notable preservation bias toward fossil vertebrates, most prominently the archosauromorph, Tanytrachelos ahynis. The geology of the Cow Branch strata continues to evoke a persistent question: Are these sediments representative of a shallow or deep lake?

I undertook a petrographic and geochemical study …

Direct And Satellite-Based Quantification Of Greenhouse Gas Fluxes In Small Ponds., Mark Christopher Tierney

Electronic Theses and Dissertations

As evidenced by their historic losses due to anthropogenic activities, wetlands are undervalued ecosystems that provide numerous ecosystem services, from recreational opportunities to carbon (C) storage. However, these wetlands are also the largest natural source of atmospheric methane (CH₄). Additionally, small water bodies (< 10,000 m²) are disproportionately large emitters relative to larger lakes and reservoirs. As construction and restoration efforts proceed, it is crucial to identify wetlands that need restoration and to understand the factors driving both greenhouse gas (GHG) fluxes and the C balance of these systems. This dissertation investigates the drivers of greenhouse gas fluxes …

Onset Of Strong Iceland-Scotland Overflow Water 3.6 Million Years Ago, Matthias Sinnesael, Boris Theofanis Karatsolis, Paul N. Pearson, Anne Briais, Sidney R. Hemming, Leah J. Levay, Tom Dunkley Jones, Ying Cui, Anita Di Chiara, Justin P. Dodd, Deepa Dwyer, Deborah E. Eason, Sarah A. Friedman, Emma Hanson, Katharina Hochmuth, Halima E. Ibrahim, Claire E. Jasper, Saran Lee-Takeda, Danielle E. Leblanc, Melody R. Lindsay, David D. Mcnamara, Sevasti E. Modestou, Margaret A. Morris, Bramley J. Murton, Suzanne Oconnell, Gabriel Pasquet, Sheng Ping Qian, Yair Rosenthal, Sara Satolli, Takuma Suzuki, Thena Thulasi, Bridget S. Wade

Department of Earth and Environmental Studies Faculty Scholarship and Creative Works

North Atlantic Deep Water (NADW), the return flow component of the Atlantic Meridional Overturning Circulation (AMOC), is a major inter-hemispheric ocean water mass with strong climate effects but the evolution of its source components on million-year timescales is poorly known. Today, two major NADW components that flow southward over volcanic ridges to the east and west of Iceland are associated with distinct contourite drift systems that are forming off the coast of Greenland and on the eastern flank of the Reykjanes (mid-Atlantic) Ridge. Here we provide direct records of the early history of this drift sedimentation based on cores collected …

Environmental Justice In Indigenous Communities: The Disproportionate Effects Of Environmental Contamination, Rae Cade, Danlin Yu, Charles Knoble, Kyle Whyte, Pankaj Lal, Cortni Borgerson

Department of Earth and Environmental Studies Faculty Scholarship and Creative Works

Indigenous communities in New Jersey, New York, and Pennsylvania (referred to as the northeastern United States) face disproportionate environmental pollution, with mortality rates 60 % higher than their white counterparts –an inequity that extends beyond formal recognition categories. While previous research has revealed pollution from facilities that cause severe health issues in Indigenous communities, broad geographic studies examining the spatial correlation between Environmental Justice (EJ) indicators and Indigenous populations remain limited. This study addresses this gap by examining contamination patterns across the northeastern United States, focusing on Superfund sites, drinking water violations, oil spills, and natural gas releases. Our analysis …

A Hedonic Analysis Of Combined Sewer Overflows (Csos) In Northern New Jersey, Taylor Wieczerak, Pankaj Lal, Pralhad Burli, Benjamin Barnett Witherell, Erik Lyttek, Bernabas T. Wolde, Ava Distaso

Department of Earth and Environmental Studies Faculty Scholarship and Creative Works

Significant water pollution caused by flooding due to heavy precipitation and extreme weather events has become a considerable problem, and changing weather patterns and sea level rise attributable to global climate change stand to further exacerbate the issue. During heavy precipitation events, combined stormwater and untreated sewage may be diverted to adjacent water bodies via combined sewer overflows (CSOs), resulting in contamination and water pollution that can be harmful to human and environmental health. Though water quality effects of CSO discharges have been studied, the socio-economic aspects of this infrastructure have not received much scientific attention. This study provides an …

Millennial-Timescale Thermogenic Co2 Release Preceding The Paleocene-Eocene Thermal Maximum, Shijun Jiang, Ying Cui, Yasu Wang, Maurizia De Palma, B. David A. Naafs, Jingxin Jiang, Xiumian Hu, Huaichun Wu, Runjian Chu, Yangguang Gu, Jiuyuan Wang, Yizhou Huang, Miquela Ingalls, Timothy J. Bralower, Shiling Yang, James C. Zachos, Andy Ridgwell

Department of Earth and Environmental Studies Faculty Scholarship and Creative Works

Geologic records support a short-lived carbon release, known as the pre-onset excursion (POE), shortly before the Paleocene-Eocene Thermal Maximum (PETM; ~ 56 Ma). However, the source and pace of the POE carbon release and its relationship to the PETM remain unresolved. Here we show a high-temporal-resolution stratigraphic record spanning the POE and PETM from the eastern Tethys Ocean that documents the evolution of surface ocean carbon cycle, redox and eutrophication, confirming the global nature of the POE. Biomarkers extracted from the sedimentary record indicate a smaller environmental perturbation during the POE than that during the PETM in the eastern Tethys …

Modeling The Greenland-Iceland-Faroe Ridge Using Integrated Geophysical Analysis, Zachary Clowdus

Department of Earth and Atmospheric Sciences: Dissertations, Theses, and Student Research

The Greenland-Iceland-Faroe Ridge (GIFR) is an area of significant geologic interest with anomalously thick crust related to enhanced melt generation from the interaction between the Mid-Atlantic Ridge and the Iceland hotspot. To the northeast of Iceland lies the Jan Mayen Microcontinent (JMMC), which is a continental fragment separated from Greenland during the opening of the Northern Atlantic. The overall extent of the JMMC, especially its southern boundary, remains poorly constrained. The crust beneath the GIFR is believed to be primarily of oceanic affinity. However, a recent discovery of felsic lavas in Iceland led to an alternative hypothesis that implies the …

Modeling Aerosol Transport During High Particulate Matter Episodes In El Paso-Juarez Region And Mitigating Mining-Related Emissions Of Rare Earth Elements (Rees) To The Air, Suzan Aranda Luna

Open Access Theses & Dissertations

This dissertation examines the use of the HYSPLIT model to develop a methodology for the transport and dispersion of air masses affecting particulate matter (PM) concentrations in the El Paso Region, and bioleaching experiments as an alternative to mitigating rare-earth concentrations in the air. Chapter 2 describes the study methodology, 3 and 4 cover the modeling methodology using two-representative high PM2.5 episodes, occurring on February 28, 2024, and June 19, 2024, respectively. These sections encompass the analysis of backward trajectories using four different meteorological datasets to build trajectory frequency maps, the exploratory model analysis of modeled outputs from lower to …

A Combined Multi-Isotope And Machine Learning Approach To Determine Groundwater Salinity And Solute Sources, Lower Valley Area, El Paso County, Texas, Gloria A. Ortiz Gamboa

Open Access Theses & Dissertations

Groundwater salinization is increasingly troublesome in aquifers in and around El Paso, Texas, where concern for available water resources has grown due to frequent droughts and increasing population. Both groundwater and surface water have experienced an increase in total dissolved solids (TDS), a trend that can pose future health and economic problems for residents who primarily rely on groundwater. To address this issue, this research focuses on the Hueco Bolson Aquifer and the Rio Grande Alluvial Aquifer within the Lower Valley area of El Paso, Texas, utilizing a multi-analysis approach to evaluate and determine solute sources and their possible end-members …

Floodplain Lake Hydrodynamic And Morphodynamic Connections Through Hydraulic Modeling Along The Pee Dee River, Sc, Charles Cj Mina

Electronic Theses and Dissertations

Rivers have been essential in the success of humankind. This reliance has created a vested interest in studying the rivers' environmental history through using floodplain deposits, with the assumption that coarser sediments correlate to higher discharge floods. However, shifting hydrological connectivity and hydrodynamics can complicate this correlation in primary repositories of flood deposits, oxbow lakes, by altering the texture of sediments delivered to them. Studying these complications is essential for quantifying paleoflood magnitude using the sediment record, but has been difficult, as the currently used index of hydrological connectivity relies on water stage, which does not reflect the sediment flux …

Essays On The Economics Of Farmland Valuation And Investment In U.S. Agriculture, Colson Tester

Graduate Theses and Dissertations

This dissertation presents three empirical essays that collectively advance the understanding of farmland valuation in key U.S. agricultural regions, emphasizing the critical advantages of comprehensive, transaction-based data over traditional survey methods. Farmland represents a significant portion of agricultural wealth, and its accurate valuation is crucial for farmers, investors, and policymakers, influencing everything from credit access to investment strategies. Historically, research has often relied on subjective survey data, which can suffer from biases, inaccuracies, and insufficient granularity. This dissertation addresses these limitations by leveraging extensive datasets of arm’s-length farmland transactions, offering a more precise and market-driven perspective on land values. The …

Spatial–Temporal Evolution Of The Box Springs Plutonic Complex, Riverside, Ca, Mateo Ospino Díaz

Loma Linda University Electronic Theses, Dissertations & Projects

The mechanisms of pluton emplacement into continental crust have long been debated in igneous geology, with early models emphasizing forceful processes such as ballooning, later contrasted by alternative emplacement mechanisms including diapirism, incremental assembly, stoping and, emplacement by sheets and dikes. These contrasting perspectives highlight the complexity of the construction of mid-crustal intrusions and the need for case studies that integrate multiple datasets. The Box Springs Plutonic Complex (BSPC) in the northern Peninsular Ranges Batholith (PRB) preserves structural, textural, and compositional features that record its emplacement and internal construction. Although its lithology, structure, and geochemistry have been described, an integrated …

Examination Of Differences Of Similar-Sized Martian Craters At The Simple-Complex Transition As Revealed By High-Resolution Imaging And Stereo-Derived Topography, Lindsey Dorn

Geosciences

Impact craters on Mars have a wide range of morphologies, and the relationship between the mechanics of their formation and their eventual morphologies is still not completely understood. By examining craters within a narrow diameter range, impact energies are constrained to similar values - enabling focused investigation of target properties and their influence on crater excavation and modification. There is a transition from simple bowl-shaped depressions to complex craters with terraced walls and central floor structures with increasing crater diameter. We analyzed target influences on morphology by examining eleven well-preserved craters of varying morphologies in the 7 to 9 km …

Multi-Scale Insar Investigations Of Anthropogenic And Natural Processes In The American Southwest, Emily Jo Graves

Geosciences

Arid regions in the American Southwest undergo measurable surface deformation driven by variations in subsurface fluid pressure, and other natural and anthropogenic processes. These processes range from regional scale aquifer dynamics to local oil and gas wellsite activities. This dissertation produces and then utilizes InSAR-derived average velocity fields and displacement time series to reveal and understand these multi-scale processes, their interactions, and impacts for a portion of the American Southwest. Chapter 1 discusses the climate and natural and anthropogenic processes present in our study area. In Chapter 2, we generate detailed large scale average velocity maps that reveal deformation associated …

Evaluating Utilidor Performance And Ground Temperature Variability In UtqiaġVik, Tate Rachow

Geosciences

Permafrost degradation in Arctic regions poses increasing risks to infrastructure as climate warming accelerates thaw processes, alters hydrology, and deepens the active layer. In Utqiaġvik, Alaska, utilidors— utility conduits—play a vital role in protecting water and wastewater services, yet their thermal performance under changing conditions remains poorly constrained. This thesis evaluates the thermal behavior of the Site U-1 direct buried pipes on Stevenson Street using historical thermistor resistance data converted to temperature, combined with calibrated two- dimensional TEMP/W numerical models. The models incorporate layered backfill materials and polyurethane insulation, while also simulating operational influences of water and wastewater temperatures. Calibration …

Engineering Risk And Indigenous Resilience Toward Intelligent Decision Support For Mining In Ancestral Lands, Izech Brian O. Edwin, King Harold A. Recto

Electronics, Computer, and Communications Engineering Faculty Publications

Mining within ancestral territories reveals an ongoing conflict between technical viability and Indigenous consent. This collaborative study, conducted by an engineering scholar and a policy researcher of Indigenous heritage in Benguet among the Ibaloi and Kankanaey peoples, investigates how risk transparency and policy alignment can bridge existing divides, while formulating principles applicable to other Indigenous mining contexts. The study provides an initial evaluation of the feasibility of a proposed large-scale mining operation within a risk-informed, data-driven governance framework. Three elements of engineering risk were assessed utilizing literature-derived and proxy parameters: (1) Land degradation is indicated by a Soil Productivity Index …

An Integrated Lithospheric Geotherm Model From Seismic Data And Plate Ages, Amanda R. Leaman

All Graduate Theses and Dissertations, Fall 2023 to Present

This research aims to develop advanced methods to accurately depict temperature profiles within the lithosphere, the Earth’s rigid outer layer. These temperature profiles extend from Earth’s surface to the asthenosphere, the ductile layer below the lithosphere. Constraining the poorly-known temperature distribution within the upper Earth is important for modeling the deformation of Earth’s crust over varying timescales and is essential for advancing realistic simulations of Earth dynamics. Here, I utilize enhanced global seismic data, coupled with recent advances in our understanding of mineral systems, to create several global lithospheric models in which I estimate temperature profiles from seismically observable features …

Using Luminescence Of Quartz Temper From Archaeological Pottery To Infer Wildfire Intensity In The Southwestern Us, Brooklyn D. Dib

All Graduate Theses and Dissertations, Fall 2023 to Present

The size and frequency of wildfires have increased recently, impacting ecosystems, communities, and human health. This research uses the heat-sensitive luminescence signals of quartz sand temper within archaeological pottery to record past wildfire conditions. Pottery sherds, which are fragments of archaeological pottery, from the forest floor in sites in New Mexico and Arizona were collected from different fire contexts (no fire exposure, historical fires, prescribed burns, and modern wildfires). These forests are primarily Ponderosa Pine with a grassy understory. The interior sand grains of each sherd sample were analyzed using optically stimulated luminescence, which dates when the mineral grains were …

A Line In The Sand: Investigating Late Pleistocene-Holocene Stratigraphy And Large-Scale Morphodynamic Evolution Along The Mississippi Coast, Carrie Miller

Dissertations

The imprints of past geomorphic evolution are embedded in the geologic record, providing valuable insights into the mechanisms that induce changes within coastal systems and the magnitude of those changes. Large-scale paleo morphodynamic evolution often occurs due to cyclonic activity, variations in sediment supply, and relative sea-level rise. The landscape of the U.S. Gulf Coast reflects a combination of erosional, depositional, hydrological, and climatic factors that remain of ongoing interest to geoscientists seeking a holistic understanding. Low- lying coastal plains, such as those along the Mississippi and Louisiana coasts, are particularly susceptible to future sea-level rise. Projected sea-level rise over …

Soil Characterization With Proximal Geophysics, Sophia M. Becker

Dissertations and Doctoral Documents, University of Nebraska-Lincoln, 2023–

High quality soil data is crucial for addressing numerous threats to human well-being such as water scarcity, food insecurity, and intensified natural disasters. True soil property values are determined by analyzing soil samples in a laboratory, but soil sampling is often expensive and time-consuming. Some in-field point sensors and remote sensing products are available to measure soil properties, but they have inherent limitations in measurement extent and resolution. Geophysical methods can fill the measurement scale gap between point measurements and remote sensing products, but various research questions remain open. This dissertation aims to advance understanding of geophysics-derived soil property measurements …

Assessing Crop Rotation Productivity, Soil Health, And Fertility, And Economic Performance, To Enhance Semi-Arid High Plains Cropping Systems Sustainability, Ezequiel Maria Villamil

Dissertations and Doctoral Documents, University of Nebraska-Lincoln, 2023–

Sustainable crop production in the semi-arid High Plains of Nebraska faces challenges from limited precipitation, high interannual variability, and economic risk. This dissertation investigates the long-term productivity, water use, soil health, and economic sustainability of dryland crop rotations, with emphasis on the role of pulses as alternatives to fallow.

Chapter 1 analyzes nearly three decades (1995–2023) of on-farm data from the High Plains Agricultural Laboratory (Sidney, Nebraska) to compare seven crop rotations, including wheat, corn, millet, sunflower, and field peas. Results showed that wheat–corn–fallow (W–C–F) consistently outperformed traditional wheat–fallow (W–F) and more intensified four-year rotations, providing the highest grain yields, …