Earth Sciences Commons^™

Mapping Sedimentary And Crustal Thicknesses In The Northern Atlantic Ocean From Public Domain Geophysical Data, Hermione Lofton

College of Arts and Sciences: Undergraduate Theses and Other Student Projects

The Northern Atlantic Ocean is a complex region that contains many inactive and active tectonic features. These features include the Jan Mayen Microcontinent, Jan Mayen Fracture Zone, Aegir Ridge, Kolbeinsey Ridge, the Greenland-Iceland-Faroe Ridge, the Voring Plateau, the Voring Spur, and the Iceland Hotspot. This project is motivated by the region’s complex geology and its highly debated tectonic history and disputed crustal affinity. This study aims to evaluate tectonic elements of the Northern Atlantic Ocean with three major objectives. The first objective is to develop a map of crustal thickness from publicly available seismic refraction data. For the second objective, …

Farm Management Practice For The Prevention Of Soil Erosion In The Carnarvon Horticultural Area, Kehinde O. Erinle

Horticulture research reports

The Carnarvon horticultural area has suffered considerable erosion damage following flooding of the Gascoyne River.

The purpose of this report is to describe the factors that contribute to soil erosion in the Carnarvon horticultural area (Section 1), provide guidelines for good soil management (Sections 2) and provide floodway hazard classes and associated soil management recommendations (Section 3).

This report:

• Provides detailed information on soil management for intensive irrigated cropping.
• Details cropping alternatives to better manage the soil erosion risk.
• Identifies appropriate plants for soil stabilisation in a range of situations.
• Promotes the concept of property management plans.
• Takes account of …

A Multi-Proxy Approach For Understanding The Chicxulub Asteroid Impact (Cretaceous / Paleogene Boundary) And Its Aftermath, Hermann D. BermúDez

Theses, Dissertations and Culminating Projects

The Chicxulub asteroid impact in what is now the Yucatan Peninsula, Mexican Caribbean, coincides with the Cretaceous/Paleogene boundary (K/Pg boundary ~66Ma) and marked the extinction of three-quarters of the species, including the iconic non-avian dinosaurs. The collision created a massive crater, releasing enormous amounts of energy and expelling millions of tons of molten and vaporized materials into the atmosphere. Chicxulub is an ideal case study for massive impact events since it is the only recognized asteroid impact on Earth's history that preserved a globally traceable ejecta layer representing a precise time-stratigraphic marker. Although numerous studies have examined the consequences of …

Tree Rings And The Broader Ocean-Atmospheric Circulation In The Highland Himalayas, Sanjaya Bhandari

All-Inclusive List of Electronic Theses and Dissertations

Climate change has altered tree-growth patterns and resulted in higher sea-surface temperatures across the planet. The Himalayan biome is one of the most vulnerable areas in the world to climate change because it has caused changes in forests’ growth and glaciers’ retreat. Dendrochronology has been used to understand the impact of climate change on tree growth and for climate reconstruction. In this dissertation, I discuss the growth of trees in the highlands of the eastern, central, and western Himalayas for the last 500 years and relate these patterns to the present global warming scenario and broad-scale climate modes. I reconstructed …

Comparison Of Nutrient Concentrations And Primary Production Indicators Across Plume Fronts, Taylor Dishon

Electronic Theses and Dissertations

Coastal buoyant plumes carry low-salinity waters containing particulate and dissolved terrestrial materials with an abundance of nutrients into the coastal ocean, including inorganic nitrogen and phosphorous. Plume fronts act as transport barriers created from the convergence of a fresher plume with an older, saltier plume or with ambient waters, leading to potential accumulation of phytoplankton and nutrients. This accumulation creates an optimal environment for primary production. The primary goals of this study were: to investigate the distribution of and potential relationships between nutrient concentrations and chlorophyll a across plume fronts of the Winyah Bay River Plume, and examine potential relationships …

A Multi-Isotope Investigation Of Mammoth Diet, Habitat, And Movement Patterns In The Central Great Plains, U.S.A., Jacob Mccloskey

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

During the Last Glacial Maximum (LGM), the Great Plains in Nebraska consisted of wooded parklands and grasslands, whereas spruce (Picea) forests, parklands, and steppe grasslands dominated east of the Missouri River. I analyzed bulk carbon (δ¹³C), oxygen (δ¹⁸O), and strontium (⁸⁷Sr/⁸⁶Sr) isotopes from tooth enamel in isolated mammoth (Mammuthus) molars to compare diet and movement patterns in two late Pleistocene assemblages: one in Nebraska (n = 24), and one in western Iowa and Missouri (n = 17). Furthermore, I identified a morphometric subset of molars as …

Multiscale Drivers Of Water Level Fluctuations And Nutrient Availability In Small Intermittent Reservoirs In The Us Midwest, Uchechukwu Vitus Chinatu Ogbenna

School of Natural Resources: Dissertations, Theses, and Student Research

Reservoir dynamics are often captured by fluctuations in water surface elevation, which reflect a complex interplay of hydrologic inputs, climatic conditions, land use influences, and management operations. While water level fluctuations (WLFs) in large regulated systems have been widely studied, the drivers and implications of WLFs in small reservoirs, particularly those fed by intermittent streams, remain poorly understood. Here, we examined the temporal dynamics of WLFs and their relationship with nutrient availability in nine small reservoirs in the U.S. Midwest using daily records from 1985 to 2022. We used water level classification from modified Zscore and transition matrices to assess …

Environmental Controls Of Hail In Quasi-Linear Convective Systems, Cameron A. Barker

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

A study of hail occurrence in quasi-linear convective systems (QLCS), as well as severe weather parameters contributing to the likelihood and intensity of hail, is presented. Rapid Refresh (RAP) proximity soundings for 218 QLCS events from 2012 to 2022 are selected to sample QLCS environments near peak intensity. Study objectives are to assess common environmental parameter spaces that favor hail in QLCSs while connecting these findings to results for supercells. Hail occurrence is also examined in terms of synoptic regime.

Six synoptic regimes were identified to support QLCSs with hail, from high shear, low cape (HSLC) to low shear, high …

Surveys And Modeling: Using An Existing Survey To Describe And Compare Populations To Better Inform On Groundwater Model Inputs, M. Austin Wise

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

The Mississippi River Valley “Alluvial Aquifer” is among the most agriculturally significant aquifers in the United States. However, parts of the aquifer are exceeding sustainable yield as development of the water source continues. Survey research in other aquifers, such as the High Plains (Ogallala) Aquifer, has helped to understand the perceptions and attitudes of irrigators withdrawing from their aquifers. This led to numerous questions: What are the attitudes of irrigators in the Alluvial Aquifer region? How do they compare to irrigators in other regions of the country? Can their intentions be used to generate more accurate inputs when modeling adoption …

Exploring The Application Of Repeated Microgravity Surveys To Monitor Groundwater Level Variations In Nebraska, Kaitlin M. Steinauer

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

Groundwater is an important resource in the state of Nebraska for supporting industries and ecosystems. Monitoring this vast resource ensures its continued availability for generations to come. However, monitoring utilizes well data, and if a well is not present in a desired location, geophysical methods can be explored. This project tests the capability of repeated gravity surveys over Nebraska’s aquifers to monitor groundwater levels throughout 2024.

Two study areas were selected in Eastern Nebraska. The first is in Oakland, Nebraska, over a confined aquifer system. The second is in Plymouth, Nebraska, and exhibits unconfined conditions. Four sites were chosen to …

Understanding The Fluid Source During Alteration Of Former Oceanic Lithosphere In The Polygenetic Ingalls Ophiolite Complex, Washington, Usa, Zachary Russell Stevens

Masters Theses

The Ingalls Ophiolite Complex is an ophiolite of Jurassic age in central WA, USA. Much of the complex formed in a supra-subduction zone setting in a back-arc ocean basin during subduction of the Farallon plate beginning 192 Ma. Between formation and obduction, mafic and ultramafic lithologies experienced alteration in the presence of water, which previous studies inferred to be seawater. Previously published δ¹⁸O and δD data from the Ingalls indicates isotopic depletion possibly caused by interaction with meteoric water at current latitude (~47.5 °N). The current study reports new δD, δ¹⁸O, and Δ ′¹⁷O measurements from mafic and ultramafic lithologies …

Quantifying The Impacts Of Land Use And Land Cover Change On Urbanizing Agricultural Systems, Carli Beisel

Boise State University Theses and Dissertations

Western water supplies are increasingly stressed by the compounding impacts of population growth, urbanization, and climate change. Rising temperatures in Idaho are shifting precipitation patterns, with more falling as rain rather than snow. This reduces snowpack and the resulting snowmelt, which serves as the predominant water source for agriculture. At the same time, urbanization of agricultural land decreases surface permeability, replaces irrigated fields, and amplifies the impacts of climate change. The Treasure Valley, located in southwestern Idaho, has been rapidly urbanizing; urban land cover has grown by 52% from 1985 to 2021. Understanding how land use and land cover changes …

Soil Carbon Storage And Its Relation To Abiotic And Biotic Factors In The Boise Foothills, Richie William Holder

Boise State University Theses and Dissertations

Terrestrial soil sequesters a significant amount of carbon (C), and changes to this pool can impact atmospheric CO2 concentrations and climate change. Thus, it is crucial to understand the drivers of the size of this pool. Changes in plant community composition in semi-arid ecosystems can impact soil C storage. However, little is known about the impact of plant functional type on the quantity and distribution of soil C on a landscape scale relevant to ecosystem management. I conducted a study in the City of Boise’s Open Space Reserves located north of Boise, Idaho to evaluate how plant functional type affects …

Unraveling Snow And Rain Contributions To Streamflow Through A Methodological Investigation On Cold And Warm Season End-Members, Rachel Grena

Boise State University Theses and Dissertations

Water supply and demand are encountering unique challenges in the western United States as climate change impacts the availability of water resources. Much of the west relies on high mountain snowpack to maintain consistent streamflow throughout the dry, warm season months. Temperatures often rise above freezing in the cold season, diminishing the snowpack size, and altering the timing of snowmelt. As droughts become more frequent, water managers are increasingly concerned about the risk of reduced summer streamflow. To understand changing hydrologic patterns, this study utilizes phase changes in precipitation, specifically the distinction between cold and warm season precipitation, and their …

A Simple Guide For Describing Soils, 2nd Edition, Angela Stuart-Street, Nicolyn Short Dr, Paul Galloway, Noel R. Schoknecht

Natural resources published reports

Soils are enormously diverse and can be very confusing to understand and talk about. This simple guide for describing soils helps to identify the most important parts of a soil profile and provide an easy way to understand and explain what you see. It gives you a step-by-step guide of what soil properties to describe and how to describe them, along with the tools to make basic soil classifications. The soil descriptors help you to identify the soil type and aid in assigning a simple and standardised name to the soil. While this guide is designed to link with a …

Using Geomorphic Change And Sediment Modeling To Calculate Debris Flow Volumes From The 2020 El Dorado Wildfire In The Southern San Bernardino Mountains, California, Sevag Injean

Electronic Theses, Projects, and Dissertations

Four years after the occurrence of the 2020 El Dorado Fire, Yucaipa Ridge and the surrounding communities of Oak Glen and Forest Falls still experience the devastation caused by debris flows. Wildfires can instigate a series of events leading to hydrophobic soils, loss of vegetation, and increased sediment availability which amplify post-fire debris flow risks. This study tested the hypothesis that post-wildfire geomorphic changes can be accurately quantified and predicted using high-resolution LiDAR-derived digital elevation models. To investigate this hypothesis, multi-temporal LiDAR datasets were analyzed to quantify geomorphic changes, including erosion and deposition, within two severely burned basins in the …

High-Resolution Event Stratigraphy Of Ostracods In The Ozan Formation Of Texas And Arkansas, Denali L. John

Master's Theses

This study focuses on the high-resolution event stratigraphic framework of the lower Campanian Ozan Formation in Northeast (NE) Texas and Southwest AR which is richly fossiliferous in ostracods. Little research has been published on the Ozan Formation and even less dealing with Ozan ostracods. Additionally, correlation of Upper Cretaceous units between Texas and AR is controversial due to the general lack of good exposures in both regions and extensive faulting in Northeast Texas despite similar depositional environment across the region. This study calibrates the ranges of ostracods and creates an event stratigraphic composite that is orders of magnitude higher in …

Influence Of Experience And Risk With Natural Hazards On Geoscience Interest And Career Expectations, Shannon Conner

All Dissertations

Understanding student interest in geoscience is important, as it has the potential to inform departmental decisions such as the selection of classroom examples and marketing strategies to attract new geoscience majors. Recruitment to geoscience is critical to address future social and environmental challenges. Our work may also provide insight into how to approach persistent recruitment problems within departments, such as student enrollment and the lack of diversity within the geosciences. This work involves developing a geoscience interest scale, integrating geospatial and educational data sets related to hazard risk and interest, and an exploring career motivations as related to natural hazard …

Terrane Accretion In The Trollheimen And Dovrefjell Regions Of The Scandinavian Caledonides, Norway, Stephanie Georgevich

Open Access Theses & Dissertations

Following closure of the Iapetus Ocean, the paleocontinents of Laurentia and Baltica collided to form the Caledonian Orogeny. During this closure and subsequent collision, island arc terranes and microcontinents were accreted and subducted underneath the Norwegian continental margin. These terranes are preserved in central Norway, specifically in the Dovrefjell and Trollheimen mountain ranges. The order in which these terranes accreted to the continent and when this occurred is not well understood. To determine this stacking order, I will be using P-T path modeling, U-Pb zircon dating, and structural position. Knowing the degree, progression, and geologic age of metamorphism, and tectonostratigraphic …

High-Frequency Seismic Noise In Desert Environments, Alexis Hernandez

Open Access Theses & Dissertations

This study investigates the generation and modulation of ambient seismic noise in arid environments, with a focus on aeolian processes such as saltation, wind shear, and precipitation events. Using a dense array of three-component seismic nodes co-located with meteorological sensors and a novel particle transport instrument (SANTRI), high-frequency seismic signatures were examined within the Jornada Experimental Range in southern New Mexico. Time-frequency analysis reveals that wind-driven saltation events produce measurable seismic energy enhancements, particularly within the 100-300 Hz band, with clear spectral distinctions between wind-only forcing and particle-laden transport. Additionally, rainfall events were identified by elevated seismic amplitudes in the …

The Origin And Geologic History Of Dolostones Associated With The Moab Valley Salt Wall, Paradox Basin, Utah, Charles Ojodale Igomu

Open Access Theses & Dissertations

This thesis investigates the origin and geologic context of dolostones associated with the Moab Valley salt wall in southeastern Utah, a feature within the broader Paradox Basin that offers an exceptional opportunity to study the interplay between carbonate sedimentation, diagenesis, and salt diapirism. The fundamental research question focuses on evaluating whether dolostones observed in the Moab Valley are all depositional, diagenetic or structurally reworked components of deeper stratigraphy, and how their presence and geometry relate to the halokinetic processes that shaped sedimentation across the Moab Valley. This study tested the hypothesis that dolostones within Moab Valley represent a mixed assemblage …

Diagenesis And Controls On Porosity And Permeability In The Upper San Andres Formation Of West Texas, Jack Butcher

Electronic Theses and Dissertations

West Texas reservoirs on the Central Basin Platform (CBP) are dominated by Permian-age carbonate deposits, significantly contributing to petroleum production. The Upper Permian-aged San Andres Formation, composed primarily of dolomite and limestone, is a prolific reservoir. This study assesses diagenetic influences on porosity and permeability within the San Andres Formation along the northern CBP. Two cores from the Monument 4-2 and Peterson 1 wells in West Texas were analyzed using core descriptions, thin section petrography, XRD, XRF, and MICP. Results indicate that dolomitization enhances porosity, with intercrystalline and moldic porosity being dominant, while late-stage cementation and compaction reduce permeability. XRD …

Development And Evaluation Of Supported Ionic Liquid Membrane And Porphyrin Frameworks For Carbon Capture Separation, Sarang Ismail

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

The global urgency to mitigate anthropogenic CO₂ emissions has intensified the pursuit of energy-efficient separation technologies. Supported Ionic Liquid Membranes (SILMs) have emerged as promising candidates for CO₂ capture due to their tunable solubility-selectivity and low energy requirements. However, challenges such as mechanical instability, limited scalability, and trade-offs in transport performance have impeded their widespread adoption.

This thesis explores a systematic approach to designing and optimizing SILMs for enhanced CO₂ separation by tailoring polymer–ionic liquid interactions, processing conditions, and material architectures. A comprehensive set of studies were conducted using poly(vinylidene fluoride) (PVDF) with varying molecular weights, different grades of PEBAX®, …

Explainable Machine Learning Surrogate Modeling For Exit Gradient Prediction In Hydraulic Structures Using Numerical Simulations, Prayas Rath, Jianting Zhu, Kevin M. Befus

Geosciences Faculty Publications and Presentations

Accurate prediction of exit gradients is essential for designing impounding hydraulic structures, such as dams and levees, to mitigate seepage-induced piping failures. Conventional analytical methods often neglect boundary effects and anisotropy, limiting their applicability in complex geological settings. This study develops an XGBoost-based machine learning surrogate model trained and tested on 8,000 MODFLOW numerical simulations to predict exit gradients under varying hydraulic and geological conditions. The data set covers numerous parameters, including anisotropy, head differences, structure width, cut-off wall depth, aquifer thickness, and uninterrupted riverbed length. The coefficient of determination for test data is 0.88, demonstrating reliable exit gradient prediction …

A Multi-Source Remote Sensing-Based Geocommunication Tool For Global Flood Monitoring And Management, Ebrahim Hamidi, Brad Peter, Hamed Moftakhari, Hamid Moradkhani

Geosciences Faculty Publications and Presentations

Global warming is expected to increase the frequency of extreme flooding, making rapid and accurate flood mapping crucial for effective risk assessment. Many governmental agencies and organizations are developing flood risk assessment tools; however, due to the lack of observational records, some rely on probabilistic generated data, uncalibrated simulations, or terrain-based methods, all of which are subject to various types of uncertainty. Although remote sensing provides valuable flood data with global coverage, single-source reliance is constrained by satellite revisit rates, resolution, weather conditions, and sensor limitations. To address these challenges, this study introduces a user-friendly application on the Google Earth …

Mantle Flow And Crustal Deformation Revealed By Seismic Anisotropy In The Subduction Zone Beneath Myanmar, Enbo Fan, Mingming Jiang, Yinshuang Ai, Stephen S. Gao, Kelly H. Liu, Yumei He, Yiming Bai, Guangbing Hou, Yuan Ling, Chit Thet Mon, Myo Thant, Kyaing Sein

Geosciences and Geological and Petroleum Engineering Faculty Research & Creative Works

The oblique convergence of the Indian and Eurasian plates drives significant deformation in the crust and mantle beneath Myanmar. However, the crustal deformation in the Indo-Burman Ranges (IBR) and mantle flow beneath Myanmar and adjacent areas remain unclear due to limited studies. We utilized data from the newly deployed second phase of the China-Myanmar Geophysical Survey of the Myanmar Orogen array to perform shear wave splitting analysis of PKS, SKKS, and SKS (XKS) phases. Our results, together with previous findings, provide new insights into mantle flow and crustal deformation across central Myanmar. In the IBR, we observed a transition from …

Decoding Teleconnection Impacts On Hydrological Switches In The Conus Using Wavelet Analysis, Surendra Maharjan, Wenzhao Li, Shahryar Fazli, Hesham Morgan, Hesham El-Askary

Mathematics, Physics, and Computer Science Faculty Articles and Research

Hydrometeorological teleconnections are key drivers of hydrological processes, representing the influence of large-scale atmospheric circulation patterns on regional climates. Understanding these teleconnections provides crucial insights into the mechanisms underlying hydrometeorological phenomena, particularly hydrological switches—rapid transitions between extreme events such as droughts and floods. These switches have become increasingly prevalent across the contiguous United States (CONUS), fueled by climate variability and evolving atmospheric patterns. This study utilizes cross-wavelet transform analysis to examine the spatial and temporal dynamics of hydrological switches and their correlations with major teleconnection indices, including NAO, ONI, WP, PDO, PNA, and QBO. The findings indicate significant coherence between …

Insights From Swot Data On Transboundary Upstream-Downstream Impacts In The Nile Basin, Hesham Morgan, Wenzhao Li, Ali Elgendy, Surendra Maharjan, Rejoice Thomas, Hesham El-Askary

Mathematics, Physics, and Computer Science Faculty Articles and Research

This study utilizes high-resolution data from NASA's Surface Water and Ocean Topography (SWOT) mission to investigate water dynamics and upstream-downstream impacts across key reservoirs in the Nile Basin. Focusing on the Grand Ethiopian Renaissance Dam (GERD), Rosaries Dam, Merowe Dam, and the Aswan High Dam, the analysis spans 15 months (August 2023 to October 2024). By systematically selecting 30 points across each reservoir, monthly boxplots of surface water elevation were generated, revealing significant temporal and spatial variability. The results show that GERD’s filling phase led to a steady increase in water levels (peaking at ~615 meters from June to October …

Assessing Meteorological Impacts On Hydrological Switches In The Conus, Surendra Maharjan, Wenzhao Li, Sujan Shrestha, Hesham El-Askary

Mathematics, Physics, and Computer Science Faculty Articles and Research

Hydrological switches, defined as rapid transitions between extreme meteorological events such as droughts and floods, are becoming increasingly frequent across the contiguous United States (CONUS) due to climate variability. This study analyzes the spatial and temporal patterns of these hydrological switches and their correlation with large-scale meteorological indices, such as the Standardized Precipitation Index (SPI) and Standardized Precipitation Evapotranspiration Index (SPEI). Streamflow data from the US Geological Survey (USGS) is analyzed to investigate the impact of meteorological drivers on hydrological variability. Results indicate that regions dependent on snowmelt exhibit delayed hydrological responses to climatic conditions, while areas in the Eastern …

Heat Storage Using High Temperature Borehole Heat Exchangers, Jack Horvath

All Theses

The use of renewable energy sources such as wind and solar power is growing, and with it comes an increased need to store excess energy when it is generated and release it on demand. Moderate temperature thermal energy storage in the subsurface is widely used to heat buildings, but high temperatures, greater than 120℃, are required to power generators that convert stored heat to electricity. High temperature heat can be generated from solar collectors or other means and then transferred to the subsurface using borehole heat exchangers (BHE). A BHE consists of a closed-loop pipe system used to circulate a …