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2026

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Articles 2131 - 2160 of 2234

Full-Text Articles in Earth Sciences

Paleoflood Chronology For The West Branch Of The Susquehanna River Using Abandoned Chute Channel Sediments, Pennsylvania, Usa, Juliette A. Vanluven Jan 2026

Paleoflood Chronology For The West Branch Of The Susquehanna River Using Abandoned Chute Channel Sediments, Pennsylvania, Usa, Juliette A. Vanluven

Honors Theses

Anthropogenic climate change is altering the hydrologic cycle, increasing flood frequency and severity, with associated increased risks in population exposure. This is associated with increasing risks to the population of the Susquehanna River Valley, which supports over 600,000 people today. However, our understanding of the frequencies of large floods is limited by relatively short instrumental records. By studying sediments from an abandoned chute channel in the Robert Allen Natural Area near Williamsport, PA, we can extend the existing flood records using paleoflood slackwater sediments along the West Branch of the Susquehanna River.  Sylvan Dell is an abandoned chute channel that …


Sedimentological Characterization Of Main And Chute Channel Scroll Bars Along The Kantishna River, Alaska, Cooper Sentz Jan 2026

Sedimentological Characterization Of Main And Chute Channel Scroll Bars Along The Kantishna River, Alaska, Cooper Sentz

Honors Theses

Scroll bars, arcuate sediment ridges found along the inner banks of river bends, are common floodplain features in meandering river systems that form during lateral channel migration. Two hypothesized formation mechanisms described in prior studies are the aggradation of suspended load onto abandoned inner bank levee (IBL) deposits during overbank flow and the migration of transverse bar packages from the channel bed up onto the point bar during flooding events. To study the sedimentology and geometry of these features, we conduct remote sensing and field analysis on a 60 km portion of the Kantishna River, AK: a highly sinuous, pro-glacial …


Deep Crustal Boundaries As Fluid Conduits: A Geochemical Investigation Of Mvt Mineralization In Kentucky And Beyond, Dairian Boddy M. Boddy Jan 2026

Deep Crustal Boundaries As Fluid Conduits: A Geochemical Investigation Of Mvt Mineralization In Kentucky And Beyond, Dairian Boddy M. Boddy

Theses and Dissertations--Earth and Environmental Sciences

Critical minerals are vital to the United States economy and national security, yet their supply chains are at risk. Common minerals in Mississippi Valley-type (MVT) deposits, such as sphalerite, galena, fluorite, and barite, host critical metals such as barium, gallium, germanium, and zinc, which are essential for energy technologies. An investigation of three MVT mineral districts in Kentucky elucidated previously unrecognized systematics, genetic relationships, and sources of ore components using stable and radiogenic isotope geochemistry, particularly from galena, sphalerite, barite, and gangue minerals (e.g., carbonates). The localization and dominant type of mineralization in each district are potentially influenced by deep …


Using Grounded Iceberg Wake Patterns To Interpret Catastrophic Flood Events In Southcentral Alaska, Jana K. Macinnis Jan 2026

Using Grounded Iceberg Wake Patterns To Interpret Catastrophic Flood Events In Southcentral Alaska, Jana K. Macinnis

All Master's Theses

Catastrophic flood events such as landslide tsunamis and jökulhlaups in glaciated areas can transport and strand icebergs, which obstruct the flow of floodwaters and leave a unique and recognizable grounded iceberg wake pattern in the sediment surface. Grounded iceberg wake patterns (GIWs) were identified at the two study areas in Southcentral Alaska; the outwash plain of a 1967 landslide tsunami at the Grewingk Glacier and proglacial lake, and the Matanuska River valley which experienced an unrecorded jökulhlaup in recent geological times. From these sites, 110 GIWs were identified through visual interpretation of lidar imagery and characterized by measuring their geometry, …


Spatial Patterns And Morphometric Evolution Of Sinkholes In Response To Watershed Hydrogeomorphology: Examples From A Karst Landscape In The Missouri Ozarks, Usa, Marcell Tóth Jan 2026

Spatial Patterns And Morphometric Evolution Of Sinkholes In Response To Watershed Hydrogeomorphology: Examples From A Karst Landscape In The Missouri Ozarks, Usa, Marcell Tóth

Graduate Theses/Dissertations

Sinkholes are characteristic enclosed depressions with internal drainage connecting the surface and subsurface karst hydrologic system. Their morphological evolution involves gradual subsidence of the ground surface and hazardous collapses. Therefore, understanding sinkhole morphometry and linked spatial distribution is critical for managing geohazards in karst watersheds. Sinkhole occurrence shows spatial variability based on watershed geomorphological attributes, surficial hydrological patterns, hydrogeological and geological settings. The aim of this research is to investigate morphometric properties and distribution of sinkholes in the carbonate karst-dominated lands of Mark Twain National Forest in Missouri, USA. The specific objectives were to (1) identify sinkhole clusters based on …


Applied Machine Learning In Mineral Prospectivity Mapping In The South Pass-Granite Mountains Of Wyoming, Carl D. York Jan 2026

Applied Machine Learning In Mineral Prospectivity Mapping In The South Pass-Granite Mountains Of Wyoming, Carl D. York

Graduate Theses/Dissertations

The South Pass-Granite Mountains, comprised of Archean to Tertiary rocks embedded with an Archean greenstone belt in Central Wyoming, have historically been mined for gold, iron, steel, and silver. Rare earth elements have been of increasing interest in the region and thus, several datasets have become available. Knowledge driven and data driven models are used in mineral prospectivity mapping with input data including geological mapping, geochemical data, geophysical (USGS Critical Mineral magnetic and gravity data), radiometric (U, Th, K) data and multispectral remote sensing data. Mineral prospectivity has seen a rapid improvement in recent years using advancements in machine learning …


Flow Regime Shifts And Channel Morphological Adjustments In Response To Changing Climate Patterns: Examples From Gasconade River, Missouri, Usa, Katherine E. Brand Jan 2026

Flow Regime Shifts And Channel Morphological Adjustments In Response To Changing Climate Patterns: Examples From Gasconade River, Missouri, Usa, Katherine E. Brand

Graduate Theses/Dissertations

Recent changes in climate patterns due to anthropogenic inputs (i.e. greenhouse gases/CO₂) have caused alterations to precipitation events leading to altered flow regimes. Changes in the magnitude and frequency of flood events results in physical adjustments to river morphology, including changes in width and depth. As rivers experience more frequent and larger flood events, they accommodate by changing their morphological characteristics. The Gasconade River, a tributary of the Missouri River located in southcentral Missouri, USA, has exhibited recent patterns of acute bank erosion with limited understanding of its causes and effects on the river. This study aims to understand how …


Field-Scale Evaluation Of Satellite- Derived Vegetation Indices And Image Timing For In-Season Nitrogen Management In Corn, Ana Morales-Ona, Katsutoshi Mizuta, James J. Camberato, Robert Nielsen, Yuxin Miao, Davide Cammarano, German Mandrini, Daniel Quinn Jan 2026

Field-Scale Evaluation Of Satellite- Derived Vegetation Indices And Image Timing For In-Season Nitrogen Management In Corn, Ana Morales-Ona, Katsutoshi Mizuta, James J. Camberato, Robert Nielsen, Yuxin Miao, Davide Cammarano, German Mandrini, Daniel Quinn

Plant and Soil Sciences Faculty Publications

Introduction: Traditional methods to determine the agronomic optimum nitrogen rate (AONR) for corn (Zea mays L.) rely on grain yield data, limiting in-season decision-making for nitrogen (N) management. Vegetation indices (VIs) derived from satellite imagery can serve as proxies for grain yield and help estimate in-season AONR, enabling timely sidedress applications. This study aimed to (1) quantify how VI–yield relationships vary during the vegetative period across fields with different tillage systems and crop residue; (2) determine whether VI–N response curves can be used to estimate AONR (AONRvi); and (3) assess the accuracy of AONRvi relative to yield-based AONR (AONRy). …


Efficient Preservation Of Old Methane-Derived Organic Carbon In Deep-Sea Surface Sediments, Rui Bao, Yangli Che, Mingzhi Liu, Naiyu Zhang, Yang Zhou, Lihua Dong, Shen Li, Owen A. Sherwood, Min Yu, Zongheng Chen, Shengxiong Yang, Nan Wang, Longhai Zhu, Jiawang Chen, Mutai Bao, Haoshuai Li, Luonan Chen, Weifeng Wu, Haiyue Ma, David J. Burdige Jan 2026

Efficient Preservation Of Old Methane-Derived Organic Carbon In Deep-Sea Surface Sediments, Rui Bao, Yangli Che, Mingzhi Liu, Naiyu Zhang, Yang Zhou, Lihua Dong, Shen Li, Owen A. Sherwood, Min Yu, Zongheng Chen, Shengxiong Yang, Nan Wang, Longhai Zhu, Jiawang Chen, Mutai Bao, Haoshuai Li, Luonan Chen, Weifeng Wu, Haiyue Ma, David J. Burdige

OES Faculty Publications

Methane released from the subseafloor is significantly attenuated during upward migration, yet the preservation of methane-derived organic carbon (OC) in global deep-sea sediments remains poorly understood. Here, we measured carbon isotopes coupled with temperature-ramped analyses on various methane seepage sediments. Our results reveal a correlation between the radiocarbon (¹⁴)C) content in deep-sea surface sediments and sulfate-methane transition depth. Notably, our findings suggest that a substantial amount of (¹⁴)C-depleted OC may originate from deep-seated methane and is efficiently preserved in surface seepage sediments. We propose that the efficient OC preservation is related to microbial-mediated aggregate formation at the seawater-sediment interface, where …


Quantifying Uncertainty In Landscape Evolution And Provenance Analysis: Insights From Statistical And Numerical Modelling, Vivian Carmello Grom Jan 2026

Quantifying Uncertainty In Landscape Evolution And Provenance Analysis: Insights From Statistical And Numerical Modelling, Vivian Carmello Grom

LSU Doctoral Dissertations

Landscape evolution models (LEMs) and detrital zircon provenance are widely used to investigate Earth surface processes, yet both face challenges related to quantifying model behavior and interpreting sedimentary signals under realistic, heterogeneous conditions. This thesis addresses these challenges through analysis and case studies that develop and apply new approaches for analyzing landscape dynamics and assessing uncertainties in sediment provenance.

Chapter 1 introduces a quantitative framework for evaluating LEM outputs using Shannon Entropy, Moran’s I, and Geary’s C. Applied to simulations with steady uplift, periodic uplift, spatially variable uplift, and a timeseries of DEMs, these metrics capture spatial organization and information …


A Hybrid Cnn-Lstm Surrogate Model For Hyper-Resolution Spatiotemporal Flood Forecasting In Norfolk, Virginia, Yidi Wang, Jonathan L. Goodall, Chetan Kumar, Diana Mcspadden, Sergio A. Barbosa, Binata Roy, Ali Shahabi, Navid Tahvildari Jan 2026

A Hybrid Cnn-Lstm Surrogate Model For Hyper-Resolution Spatiotemporal Flood Forecasting In Norfolk, Virginia, Yidi Wang, Jonathan L. Goodall, Chetan Kumar, Diana Mcspadden, Sergio A. Barbosa, Binata Roy, Ali Shahabi, Navid Tahvildari

Data Science Faculty Publications

Study region

Norfolk, Virginia, United States

Study focus

Accurate and timely flood forecasting is essential for enhancing resilience in coastal urban areas in the context of increasing frequency and intensity of rainfall, sea level rise and urbanization. This study presents a hybrid deep learning-based surrogate model that integrates Convolutional Neural Networks (CNN) and Long Short-Term Memory (LSTM) networks to enable real-time spatiotemporal flood forecasting. The model leverages CNN to capture spatial features from inputs such as elevation and Topographic Wetness Index (TWI), while LSTM processes time-series inputs of rainfall and tide data to capture temporal features.

New hydrologic insights for …


New Fossil Mygalomorph Spiders (?Idiopidae, Pycnothelidae) From The Lower Cretaceous Crato Formation Of Brazil, Elis Maria Gomes Santana Jan 2026

New Fossil Mygalomorph Spiders (?Idiopidae, Pycnothelidae) From The Lower Cretaceous Crato Formation Of Brazil, Elis Maria Gomes Santana

Graduate Theses, Dissertations, and Problem Reports (ETD)

The infraorder Mygalomorphae represents one of the earliest-diverging lineages of spiders, but its fossil record remains sparse relative to the modern diversity of the group. This is a reflection of both ecological and preservational biases, such as the predominantly fossorial habits of many mygalomorphs and the strong bias of the spider fossil record toward amber deposits. Compression fossils from rock deposits are therefore especially important for documenting the evolutionary history of the group. Here, two new mygalomorph fossils from the Lower Cretaceous Crato Formation, Araripe Basin (Brazil) are described. The first specimen is tentatively referred to ?Idiopidae based on male …


A New Parsimony-Based Method For Reconstructing Sequences Of Developmental Events And Estimating Rates Of Intraspecific Variation, With Applications To Trilobites, Alexander Benjamin Bradley Jan 2026

A New Parsimony-Based Method For Reconstructing Sequences Of Developmental Events And Estimating Rates Of Intraspecific Variation, With Applications To Trilobites, Alexander Benjamin Bradley

Graduate Theses, Dissertations, and Problem Reports (ETD)

Ontogenetic Sequence Analysis (OSA) is a method for reconstructing multiple sequences of abrupt phenotypic transformations (developmental events) for sampled populations of any kind of organism. It makes use of cladistic parsimony software to produce a network, or graph, whose vertices represent unique phenotypes at different stages of maturity (“semaphoronts”) and whose edges describe the developmental events occurring between semaphoronts. It is a powerful tool for constraining the range of developmental variation possible for a given species and generating sample statistics capable of identifying both the most common and the outlier ontogenetic sequences. However, OSA has seen little use since its …


Comparing Unet And Hrnet For Geomorphic Feature Extraction From Digital Terrain Model-Derived Land Surface Parameters, Behnam Solouki Jan 2026

Comparing Unet And Hrnet For Geomorphic Feature Extraction From Digital Terrain Model-Derived Land Surface Parameters, Behnam Solouki

Graduate Theses, Dissertations, and Problem Reports (ETD)

Automated extraction of geomorphic features from high spatial resolution terrain data is important for environmental monitoring, geohazard assessment, and landscape change analysis. This study compares two convolutional neural network architectures, UNet and High-Resolution Network (HRNet), for semantic segmentation of mine benches and sinkholes from lidar-derived digital terrain models and land surface parameters. Mine benches represent anthropogenic, elongated, stepped landforms associated with historic surface mining, whereas sinkholes are natural, compact depressions common in karst terrain. Three terrain-derived input layers were used: square-root-transformed slope, broad-scale topographic position index, and fine-scale annulus topographic position index. Models were trained using five training sample sizes, …


Preliminary Analysis Of Soil Volatile Organic Compounds As Soil Health Indicators, Thorne Taul Jan 2026

Preliminary Analysis Of Soil Volatile Organic Compounds As Soil Health Indicators, Thorne Taul

Graduate Theses, Dissertations, and Problem Reports (ETD)

Over the past decade, soil health (SH) has gained popularity due to the novelty of sustainable soil use related to human wellbeing. Soil health describes the overall quality of soil and its capacity to function over time. As interest in SH grows, researchers continue to explore new soil health indicators that can improve knowledge on how soil health is assessed and managed. Some indicators directly reflect soil health status, and some indirectly relate to processes and functions occurring within the soil. Volatile organic compounds (VOCs) are naturally occurring compounds that play a role in multiple soil processes. They are associated …


Sedimentological And Geochemical Investigation Of The Origin Of Upper Pennsylvanian Black Shales, East-Central Appalachian Basin, Tyler Hickey Jan 2026

Sedimentological And Geochemical Investigation Of The Origin Of Upper Pennsylvanian Black Shales, East-Central Appalachian Basin, Tyler Hickey

Graduate Theses, Dissertations, and Problem Reports (ETD)

In the east-central Allegheny foreland basin, laminated black shales overlying Upper Pennsylvanian Glenshaw Fm. coal seams record paleoenvironmental conditions associated with the termination of peat swamp deposition before, during, and after the Carboniferous Coal Forest Collapse (CCFC), a major paleobotanical evolutionary event during the Late Paleozoic Ice Age (LPIA) that contributed to extinction of lepidodendrons near the Desmoinesian-Missourian boundary (~306 Ma). Previous investigations of the CCFC commonly implicate an episode of aridification during intensification of LPIA glaciation that stressed the lepidodendrons beyond their ecological tipping point; however, the cause of this aridification is unclear. An investigation of Glenshaw Fm. black …


Data-Driven Methodologies For Mapping Cultural Heritage: The Case Of The National Coal Heritage Area, West Virginia, Usa, Hossain Mohammad Nahyan Jan 2026

Data-Driven Methodologies For Mapping Cultural Heritage: The Case Of The National Coal Heritage Area, West Virginia, Usa, Hossain Mohammad Nahyan

Graduate Theses, Dissertations, and Problem Reports (ETD)

The objective of this dissertation was to develop a comprehensive, data-driven spatial framework for characterizing the complex cultural landscape of the National Coal Heritage Area (NCHA) in West Virginia. By transitioning away from traditional, heuristic spatial mapping, this research integrates advanced spatial statistics, machine learning, and GIS-based methodologies to objectively quantify the physical, visual, and cultural dimensions of the post-mining environment. The research is structured around three interconnected empirical studies, each addressing a specific scale of the Landscape Character Assessment (LCA) framework to support heritage conservation and sustainable spatial planning. The first paper focused on landform classification, developing an automated …


Applying Transfer Learning For Street-Scale Nuisance Flood Forecasting In Coastal-Urban Environments, Binata Roy, Jonathan L. Goodall, Diana Mcspadden, Chetan Kumar, Steven Goldenberg, Yidi Wang, Malachi Schram Jan 2026

Applying Transfer Learning For Street-Scale Nuisance Flood Forecasting In Coastal-Urban Environments, Binata Roy, Jonathan L. Goodall, Diana Mcspadden, Chetan Kumar, Steven Goldenberg, Yidi Wang, Malachi Schram

Data Science Faculty Publications

An important challenge with Machine Learning (ML) is its transferability; that is, whether an ML model trained on one set of data can be applied to a second set of data without requiring full retraining of the model. Transfer Learning (TL) addresses this challenge by transferring knowledge learned in the source domain (the data it was trained on) to the target domain (a second set of data that is statistically different but related, which the model was not trained on). This study investigates the use of TL for street-scale nuisance flood forecasting by exploring whether an ML model trained for …


High Algal Biomass Is Decoupled From Metabolism In The Gallatin River, Cora Mae Steinbach Jan 2026

High Algal Biomass Is Decoupled From Metabolism In The Gallatin River, Cora Mae Steinbach

Graduate Student Theses, Dissertations, & Professional Papers

Assessing eutrophication in rivers is difficult compared to lakes and coastal waters, because most algal biomass occurs on the riverbed and flows interact and co-vary with production (Biggs and Close, 1989; Bernhardt et al., 2018). Riverine eutrophication is typically assessed using algal biomass and water column nutrients (U.S. Environmental Protection Agency, 2000), but biomass is highly variable and labor-intensive to measure, while nutrient concentrations often underestimate enrichment due to rapid biological uptake (Dodds and Smith, 2016). Reach-scale river metabolism can help evaluate long-term functional change in rivers recovering from nutrient enrichment (Arroita et al., 2019; Jankowski et al., 2021; Diamond …


Supporting Data – T-3 Stream Stage And Streambed Well Data, Mclean County, Il, April 12, 2025 To November 1, 2025, Eric Wade Peterson, Eric Brunner Jan 2026

Supporting Data – T-3 Stream Stage And Streambed Well Data, Mclean County, Il, April 12, 2025 To November 1, 2025, Eric Wade Peterson, Eric Brunner

Faculty Publications - Geography, Geology, and the Environment

Between April 12, 2025, and November 1, 2025, observation wells at the T-3 site in central Illinois were monitored at an upstream and downstream site along the stream. A conductivity, depth, and pressure (CTD) sensor inside each well collected continuous in-situ measurements for the water column height (mm), the water temperature (°C), and the water conductance (mS/cm). The available dataset provides in-situ readings every 15-minutes from seven (7) locations: upstream stream, streambed, and shallow aquifer, downstream stream, streambed, and shallow aquifer, and Well 12, and provides the air temperature.


Þingmúli Revisited: New Zircon-Based Perspectives On Rhyolite Petrogenesis In Iceland, Tenley J. Banik, Tamara L. Carley, Cameron D. Essex, Gabriella M. Montano Jan 2026

Þingmúli Revisited: New Zircon-Based Perspectives On Rhyolite Petrogenesis In Iceland, Tenley J. Banik, Tamara L. Carley, Cameron D. Essex, Gabriella M. Montano

Faculty Publications - Geography, Geology, and the Environment

Þingmúli (Thingmuli), an extinct volcano in eastern Iceland, has long been an archetype for fractional crystallization of tholeiitic basalt to produce rhyolite. However, a recent re-examination of Þingmúli suggests that some silicic magmas were produced under more oxidizing conditions from a combination of magma mixing and assimilation, thereby indicating two petrogenetic pathways. We present the first zircon-based analyses from Þingmúli to evaluate the extent to which the zircon record corroborates these recent findings. Zircon U-Pb age dates of ~ 8.5–10 Ma agree with published whole-rock and regional values. Zircon εHf ranges from ~ + 13.6 to 16.3; zircon δ …


Analyzing A Benchtop Model Of Combined Heat Power To An Industrial Scale, Chase Steven Carlton, Ashley Leach, Andrew Martin-Biggs, Tessa Wilker Jan 2026

Analyzing A Benchtop Model Of Combined Heat Power To An Industrial Scale, Chase Steven Carlton, Ashley Leach, Andrew Martin-Biggs, Tessa Wilker

UNH URC Open (2026 and after)

Analyzing a Benchtop Model of Combined Heat Power to an Industrial Scale


Climate Change Effects On Biomass And Greenhouse Gas Emissions Are Ameliorated By Nontoxic Endophytes In Southeastern Usa Transition Zone Tall Fescue Pastures, Rebecca Kay Mcgrail, Jonathan D. Moore, A. Elizabeth Carlisle, Jim A. Nelson, Rebecca L. Mcculley Jan 2026

Climate Change Effects On Biomass And Greenhouse Gas Emissions Are Ameliorated By Nontoxic Endophytes In Southeastern Usa Transition Zone Tall Fescue Pastures, Rebecca Kay Mcgrail, Jonathan D. Moore, A. Elizabeth Carlisle, Jim A. Nelson, Rebecca L. Mcculley

Plant and Soil Sciences Faculty Publications

Background: The plant–microbe interaction between tall fescue and its endophyte Epichloë coenophiala can affect ecosystem responses to changing rainfall patterns and increasing temperatures. Endophyte-infected (E+) stands often exhibit improved stress tolerance and differing soil greenhouse gas (GHG) emissions compared to endophyte-free (E−) stands. However, it is unknown if mammalian nontoxic endophyte (NTE) strains introduced into some tall fescue cultivars confer differing stress tolerances or reduce soil GHG emissions.

Methods: We quantified the impact of fescue-NTE symbioses in Jesup and Texoma on biomass and GHG emissions in response to increased temperature (+3°C) and altered precipitation (50% lengthened interval between events) using …


A Global Synthesis Of Fragipan Silicon Concentrations And Relationships With Soil Physicochemical Properties As A Function Of Soil Parent Materials, Christopher Shepard Jan 2026

A Global Synthesis Of Fragipan Silicon Concentrations And Relationships With Soil Physicochemical Properties As A Function Of Soil Parent Materials, Christopher Shepard

Plant and Soil Sciences Faculty Publications

Fragipans are dense, brittle subsurface horizons that restrict root growth and limit water-holding capacity. A common factor in these soils is a binding agent, potentially either phyllosilicate clay bridging, amorphous aluminosilicate/silica, or silica sorbed to Fe oxides. Others have suggested that no binding agent is present within these soil horizons and that the arrangement of individual particles is solely responsible for these horizons. In this article, a secondary data synthesis was utilized to demonstrate that silicon (Si) accumulation is a key pedogenic process in loess-derived fragipan horizons, but not in all fragipans. The average dithionite-extractable Si (Sid) content …


Modeling The Development Of Keyhole Passage Morphology, Charlotte Boehme Jan 2026

Modeling The Development Of Keyhole Passage Morphology, Charlotte Boehme

2026 Research Poster Competition

Cave passage morphology is an important indicator of the hydrological conditions under which a cave passage was formed. Keyhole passages are a commonly occurring type of passage morphology that consists of a round, wide top with a smaller canyon incised in the bottom of the passage. These passages typically indicate a shift from fully water-filled to partially water-filled conditions. There are multiple mechanisms by which such a transition can occur, and little is understood about which of these mechanisms is most common, or whether aspects of keyhole passage morphology may indicate the primary formation mechanism. CaveCHAMP is a physically based …


Chronostratigraphy Using Stable Carbon Isotopes Of The Elliot Formation, South Africa, Aidan Del Pino Jan 2026

Chronostratigraphy Using Stable Carbon Isotopes Of The Elliot Formation, South Africa, Aidan Del Pino

2026 Research Poster Competition

The Elliot Formation in South Africa preserves a fossil-bearing record spanning the Late Triassic–Early Jurassic, a time marked by significant environmental changes related to the Central Atlantic Magmatic Province (CAMP) and the end-Triassic extinction event. Despite its importance, the Elliot Formation remains poorly constrained due to limited chronostratigraphic markers. Chronostratigraphy is the branch of geology that correlates and dates rock units in time, allowing researchers to arrange these rock units into a chronological sequence. Globally, the Triassic–Jurassic boundary is characterized by a pronounced negative carbon isotope excursion linked to CAMP volcanism and the end Triassic extinction event. This C-isotope excursion …


Origin Of The World-Class Eagle, Eagle East, And Tamarack Ni-Cu-Pge Deposits And Comparative Analysis With Other Midcontinent Rift- And Siberian Trap-Related Intrusions, Robert M. Nowak Jan 2026

Origin Of The World-Class Eagle, Eagle East, And Tamarack Ni-Cu-Pge Deposits And Comparative Analysis With Other Midcontinent Rift- And Siberian Trap-Related Intrusions, Robert M. Nowak

Dissertations, Master's Theses and Master's Reports

The 1.1 Ga Mesoproterozoic Midcontinent rift hosts the Eagle, Eagle East, and Tamarack Ni-Cu-PGE deposits and Embayment Prospect. These deposits are hosted by ultramafic igneous rocks and have some of the highest Ni-Cu grades on Earth. We use new bulk-rock data and published datasets (bulk-rock, mineral chemistry, and isotopic analyses) to examine major, minor, and trace element trends of both Midcontinent rift-related alkaline and tholeiitic intrusions. In addition, we compare the geochemical data to local kimberlite-hosted lower-crustal xenoliths and local igneous (Archean) and sedimentary (Paleoproterozoic) country rocks. We found the peridotite magma compositions dominantly consist of primitive mantle compositions with …


High-Resolution Mapping Of Soil Moisture Variation Using Uas Thermal And Multispectral Imagery, Jackline Amma Timah Jan 2026

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 Jan 2026

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 Jan 2026

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 …