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Re-Crosslinkable Hyper-Branched Polymer Gels Based On A Transamidation Reaction, Tao Song, Baojun Bai, Thomas P. Schuman Jan 2026

Re-Crosslinkable Hyper-Branched Polymer Gels Based On A Transamidation Reaction, Tao Song, Baojun Bai, Thomas P. Schuman

Patents

The present invention generally relates to the field of conformance control in oil fields, particularly to a re-crosslinkable preformed particle gel system, and composition thereof. The composition of the re-crosslinkable preformed particle gel system contains monomers, crosslinkers, a polymer matrix, and additives. Components in the composition for re-crosslinkable preformed particle gel in the present invention have excellent compatibility with each other, and the obtained gel has excellent long term high-temperature resistance property. Different from prior products, in the recrosslinkable preformed particle gel compositions according to embodiments of the present invention, the components that are used to re-crosslink the particle gels …


Modeling The Effects Of Subsurface Tile Drainage On Atrazine And Nitrate Transport In Till Soils Of Iowa, Madison Hobbs Jan 2026

Modeling The Effects Of Subsurface Tile Drainage On Atrazine And Nitrate Transport In Till Soils Of Iowa, Madison Hobbs

West Chester University Graduate Theses, Dissertations, and Final Projects

Tile drainage design influences groundwater flow pathways, residence time, and agrochemical transport in agricultural soils. This study evaluates how differences in drainage design affect subsurface flow behavior and contaminant transport in glacial till soils. A groundwater model was developed to compare conventional and controlled drainage systems with a shallow drainage system, and particle tracking was used to examine flow paths and residence times.

The results show that tile drainage creates distinct shallow and deeper flow pathways. In the conventional and controlled model, 88% of particles were captured by drains, while 12% reached the general head boundary. The shallow system drains …


Investigating Netarts Bay, Oregon Coastal Landscape Change From Tectonic Subsidence Through Isotopic, Stratigraphic Records And Quantifying Dune Influence On Salt Marsh Morphodynamics, Emily Hall Jan 2026

Investigating Netarts Bay, Oregon Coastal Landscape Change From Tectonic Subsidence Through Isotopic, Stratigraphic Records And Quantifying Dune Influence On Salt Marsh Morphodynamics, Emily Hall

Open Access Master's Theses

Coastal salt marshes on tectonically active margins face dual pressures from episodic seismic events and anthropogenic modifications. This study investigated how the 1700 CE Cascadia Subduction Zone earthquake and the 1900 CE introduction of invasive dune grass influenced back-barrier salt marsh morphodynamics at Netarts Bay, Oregon. It was hypothesized that (1) salt marsh habitats and elevation transitions would be detectable in geochemical proxies preserved in stratigraphy, (2) modern dune stabilization significantly limits mineral sediment delivery to the salt marsh, and (3) this reduction would be preserved in the stratigraphic record. Stratigraphic and isotopic analyses of sediment cores incorporating CT scans, …


Evolution Of A Managed Flood-Tide Delta And Barrier-Beach System, Charlestown, Rhode Island, Zachary Justin Levitan Jan 2026

Evolution Of A Managed Flood-Tide Delta And Barrier-Beach System, Charlestown, Rhode Island, Zachary Justin Levitan

Open Access Master's Theses

Barrier-beach and estuarine areas are important ecologically and economically, and the inlets connecting them are critical for ocean exchange and greatly dynamic. Man-made jetties are often installed to maintain the connection between ocean and estuary for navigation and water quality benefits. With storms and sea-level rise, coastal systems are changing over days to decades, affecting communities in New England and around the globe. This study utilized remotely sensed data (i.e., aerial imagery, lidar, and sonar) to examine the dynamics of the Charlestown Breachway and its flood-tide delta in southern Rhode Island, USA over varying times scales. The specific research objectives …


Insights Into The Petrogenesis Of Alkalic, Shonkinitic Magmas From The Adel Hill Volcanic Field, Montana, Kenneth L. Brown, C. L. Mcleod, M. L. Lytle, T. J. Cracas, B. J. Shaulis, M. Loocke Jan 2026

Insights Into The Petrogenesis Of Alkalic, Shonkinitic Magmas From The Adel Hill Volcanic Field, Montana, Kenneth L. Brown, C. L. Mcleod, M. L. Lytle, T. J. Cracas, B. J. Shaulis, M. Loocke

Geology and Environmental Geoscience Faculty Publications

Shonkinites are rare alkali-rich igneous rocks found in the geological record from the Precambrian to the Eocene. This study investigates the Upper Cretaceous shonkinites from the Adel Hills Volcanic Field (AHVF), central Montana. The AHVF shonkinites are porphyritic with large, euhedral to subhedral phenocrysts of diopside that exhibit sector zoning. Other major mineral phases include plagioclase, sanidine, and secondary zeolites. Minor and accessory phases identified with SEM-EDS include magnetite, apatite, rare ilmenite and pyrite, and secondary calcite. Bulk rock SiO2 ranges from 47 to 49 wt% with Na2O + K2O varying from 5.50 to 7.34 wt% within that silica range. …


Effects Of Short-Term Exposure To Environmentally Relevant Pesticides Mixture On Morphological Alterations, Oxidative-Nitrative Stress Biomarkers, Cellular Apoptosis, And Antioxidant Expression In Kidneys Of Goldfish, Esmirna Cantu, Md Saydur Rahman Jan 2026

Effects Of Short-Term Exposure To Environmentally Relevant Pesticides Mixture On Morphological Alterations, Oxidative-Nitrative Stress Biomarkers, Cellular Apoptosis, And Antioxidant Expression In Kidneys Of Goldfish, Esmirna Cantu, Md Saydur Rahman

School of Earth, Environmental, & Marine Sciences Faculty Publications

Chemical stressors are pervasive, affecting both terrestrial and aquatic environments. The continual influx of these toxins is damaging ecosystems and the organisms that inhabit them. The abundance of environmental toxins makes aquatic habitats inhospitable for aquatic life. These chemical stressors consistently disrupt the life processes of aquatic organisms, particularly their physiological functions. This study examined on the effects of environmentally relevant pesticides mixture (low-dose and high-dose: S-metolachlor: 2.4 go/L, 12 μg/L; linuron: 2.0 μg/L, 10 μg/L; isoproturon: 1.2 μg/L, 6.0 μg/L; tebucanozole: 1.2 μg/L, 6.0 μg/L; aclonifen: 0.8 μg/L, 4.0 μg/L; atrazine: 0.4 μg/L, 2.0 μg/L; pendimethalin: 0.4 μg/L, 2.0 …


Changepoint Analyses Confirms Global Tropical Cyclone Frequency Decline, Michael Wehner, Thomas Fisher, Norou Diawara, Robert Lund Jan 2026

Changepoint Analyses Confirms Global Tropical Cyclone Frequency Decline, Michael Wehner, Thomas Fisher, Norou Diawara, Robert Lund

Mathematics & Statistics Faculty Publications

Changes in tropical cyclone frequencies as the climate warms is a topic of significant current debate [1, 2]. There is no accepted theory of how tropical cyclogenesis might respond to a warmer ocean-atmosphere system as multiple controlling factors exist [3–7]. Anthropogenic warming of surface ocean temperatures due to increased greenhouse gas concentrations [8] increases the potential for tropical cyclogenesis [9–11]; however, realized cyclogenesis also requires an initial local disturbance [12–16] to develop. Most multi-decadal tropical cyclone permitting climate models (i.e. resolutions of 15-50km) exhibit frequency decreases in warmer climates, despite the increase in tropical cyclogenesis potential [17–25]. In this paper, …


The Adaptive Solution Of High-Frequency Helmholtz Equations Via Multi-Grade Deep Learning, Peiyao Zhao, Rui Wang, Tingting Wu, Yuesheng Xu Jan 2026

The Adaptive Solution Of High-Frequency Helmholtz Equations Via Multi-Grade Deep Learning, Peiyao Zhao, Rui Wang, Tingting Wu, Yuesheng Xu

Mathematics & Statistics Faculty Publications

The Helmholtz equation is fundamental for modeling wave propagation in acoustics, electromagnetics, and geophysics; however, high-frequency regimes remain notoriously difficult due to the severe numerical “pollution effect.” We propose FD-MGDL, an adaptive framework that synergizes finite difference discretizations with Multi-Grade Deep Learning (MGDL) to efficiently resolve high-frequency wavefields. Unlike standard physics-informed neural networks (PINNs), which frequently suffer from spectral bias and heavy automatic differentiation overhead, FD-MGDL employs a progressive, grade-wise training strategy that incrementally incorporates shallow sub-networks to refine residual errors. By leveraging ReLU activations in refinement grades, the framework reformulates the highly non-convex global optimization problem into a sequence …


Urban Trees In The Urban Hydrology Cycle, Jorge R. Vera Jan 2026

Urban Trees In The Urban Hydrology Cycle, Jorge R. Vera

Theses, Dissertations and Capstones

In urban forestry, trees provide numerous economic, ecological, and aesthetic benefits to the surrounding community. One of their key roles is intercepting stormwater runoff, reducing flooding risk, and improving water quality. Chapter 1 of this thesis characterized the ecological and economic contributions of urban trees on the Marshall University campus and provides guidance on their management and conservation in the future. Chapter 2 examined how urban tree species modify the urban hydrology cycle by altering the volume and timing of precipitation delivery. In Chapter 1, we inventoried 114 acres of Marshall University's main campus in Huntington, WV, from June 28 …


Solubility And Dissolution Mechanism Of Novel Multi-Ester Headgroup Surfactants In Supercritical Co2, Ning Xu, Yan Ling Wang, Baojun Bai, Shi Zhang Cui, Yu Zhang, Wen Jing Shi, Zhao Nian Zhang, Wen Hui Ding, Pei Xu Ma, Zan Gao Jan 2026

Solubility And Dissolution Mechanism Of Novel Multi-Ester Headgroup Surfactants In Supercritical Co2, Ning Xu, Yan Ling Wang, Baojun Bai, Shi Zhang Cui, Yu Zhang, Wen Jing Shi, Zhao Nian Zhang, Wen Hui Ding, Pei Xu Ma, Zan Gao

Geosciences and Geological and Petroleum Engineering Faculty Research & Creative Works

To address the limited solubility and applicability of conventional hydrocarbon surfactants in supercritical CO2, a series of multi-ester headgroup surfactants were designed and synthesized by leveraging the CO2-philic properties of ester groups. The molecular structures were characterized using Fourier transform infrared (FT-IR) spectroscopy and 1H NMR. A custom-designed laser-based apparatus was developed to quantify surfactant solubility and systematically investigate phase behavior in CO2. Molecular dynamics (MD) simulations were employed to elucidate structure–solubility relationships across multiple scales, including solubility parameters, interaction energies, radial distribution functions (RDFs), and free volume fractions. Results indicate that, at 323.15 K, …


Early Successional Response To Stream Daylighting In Redwood National And State Parks, Orick, California, Rylee Rawson Jan 2026

Early Successional Response To Stream Daylighting In Redwood National And State Parks, Orick, California, Rylee Rawson

Cal Poly Humboldt theses and projects

In-channel stream restoration projects can act as both disturbance and recovery mechanisms, disrupting existing conditions to reestablish the hydrologic and ecological processes that sustain stream ecosystems. These interventions initiate successional trajectories in which channel form and biological communities reorganize over time. In Redwood National and State Parks (California, USA), the Redwoods Rising initiative restores buried headwater channels by recontouring legacy logging roads and daylighting streams buried by Humboldt crossings. Using the National Park Service Klamath Network wadable stream monitoring protocol, I evaluated nine restored reaches spanning one to five years post-restoration, alongside old-growth reference reaches and available pre-treatment data. I …


Swimming In Uncertainty: Filling Data Gaps And Providing An Educational Platform For Beach Water Quality At Tybee Island, Georgia, Lukas Roberson Jan 2026

Swimming In Uncertainty: Filling Data Gaps And Providing An Educational Platform For Beach Water Quality At Tybee Island, Georgia, Lukas Roberson

College of Graduate Studies: Theses & Dissertations

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Swimming in beaches water contaminated with high levels of bacteria can make you sick. Current monitoring at the public beaches on Tybee Island consists of weekly monitoring and enumeration of fecal indicator bacteria that takes 24 hours for results. If the number of bacteria exceed regulatory limits, a public health advisory is issued, and affected waters are retested until …


Geospatial Analysis Of Sinkhole Density And Characteristics In West Virginia, Marissa Shannon Loftus Jan 2026

Geospatial Analysis Of Sinkhole Density And Characteristics In West Virginia, Marissa Shannon Loftus

Graduate Theses, Dissertations, and Problem Reports (ETD)

Creation of a sinkhole map of West Virginia provides useful data to help identify areas susceptible to sinkhole related hazards, as well as allowing for detailed analysis of factors controlling karst development. Newly available, statewide LiDAR-derived digital elevation data have made mapping sinkholes over larger spatial extents feasible. For this study, sinkholes were mapped for all areas of West Virginia that are underlain by carbonate rocks; then the distribution and characteristics were evaluated overall and in four focus areas (Berkeley and Jefferson counties, Pendleton County, Greenbrier County, and Monroe County). These areas correspond to broader physiographic regions, with Berkeley, Jefferson, …


Deposition And Diagenesis Of Permo-Triassic Gypsum From Wyoming And Texas: Saline Lake And Groundwater Systems Of Equatorial Pangea, Maya Yamei Bradford Jan 2026

Deposition And Diagenesis Of Permo-Triassic Gypsum From Wyoming And Texas: Saline Lake And Groundwater Systems Of Equatorial Pangea, Maya Yamei Bradford

Graduate Theses, Dissertations, and Problem Reports (ETD)

Knowledge of gypsum textures and the processes that yield them is important for interpreting the history of environments, climates, and life on Earth. This is because gypsum textures are products of specific environmental, microbiological, and diagenetic processes, and because gypsum is relatively common in the Earth’s sedimentary record. Despite this significance, gypsum is relatively understudied. The fundamental goal of this dissertation is to advance our understanding of gypsum textures by presenting detailed, petrography-based investigations of Permo-Triassic gypsum from the continental interior of Pangea.

Gypsum is typical in the Permo-Triassic sedimentary record of tropical Pangea, where it is associated with red …


Application Of Organic Geochemistry To The Characterization Of Hydrochar And Biochar: Insights Into Composition And Optimization, Michael A. Kruge, Teresa A. Centeno, Alvaro Amado-Fierro, José Manuel González-Lafuente, Rubén Forján, José Luis Gallego Jan 2026

Application Of Organic Geochemistry To The Characterization Of Hydrochar And Biochar: Insights Into Composition And Optimization, Michael A. Kruge, Teresa A. Centeno, Alvaro Amado-Fierro, José Manuel González-Lafuente, Rubén Forján, José Luis Gallego

Department of Earth and Environmental Studies Faculty Scholarship and Creative Works

Hydrothermal carbonization has garnered significant attention in recent studies due to potential applications of the hydrochar produced, which overlap with those of torrefied biochar, including soil improvement, carbon sequestration, and energy production. However, unlike the relatively uniform properties of biochar, hydrochar characteristics can vary greatly depending on the feedstock used. Advanced characterization techniques are essential to better understand these materials and enhance their practical applications. Research on hydrochar requires a multi-faceted approach, including molecular-level studies, to optimize production processes and identify specific applications.

In this regard, analytical methods commonly used in organic geochemistry could play a crucial role in deepening …


Non-Destructive Characterization Of Variously Colored Gypsum And Aragonite/Calcite Speleothems From The Cigalère Cave (Ariège, France), Martin Vlieghe, Johan Wouters, Gérald Fanuel, Jean-François Drion Du Chapois, Anne Gallez, Stéphane Pire-Stevenne, Gaëtan Rochez, Johan Yans Jan 2026

Non-Destructive Characterization Of Variously Colored Gypsum And Aragonite/Calcite Speleothems From The Cigalère Cave (Ariège, France), Martin Vlieghe, Johan Wouters, Gérald Fanuel, Jean-François Drion Du Chapois, Anne Gallez, Stéphane Pire-Stevenne, Gaëtan Rochez, Johan Yans

International Journal of Speleology

The Cigalère Cave is a 21 km-long karstic cave located in the Ariège Department, in the French Pyrenees, and underlies directly the Bentaillou Pb-Zn-Fe sulfide ores. The cave hosts abundant gypsum mineralizations, some of them exhibiting various colorations including blue, yellow, purple, orange and black. Due to strict preservation policies, these colored mineralizations have not been studied much. Here we propose a non-destructive characterization of five distinct gypsum or carbonate speleothem structures from the Cigalère, exhibiting different colorations. To comply with the preservation policies, no sample was taken from the cave, and all speleothems were analyzed in situ using portable …


Temporal Patterns Of Storm Surges: Event-Identification, Clustering, And Count Modeling, Ariadna Martin Oliva Jan 2026

Temporal Patterns Of Storm Surges: Event-Identification, Clustering, And Count Modeling, Ariadna Martin Oliva

Graduate Studies Theses and Dissertations 2026

Coastal regions face compounding risks when extreme events strike in rapid succession, yet most statistical frameworks treat such events as independent, a simplification that can critically underestimate hazard. This thesis addresses that gap through three interconnected contributions focused on the temporal clustering of storm surges at the global scale. A new automated method is developed to extract independent storm surge events from continuous tide gauge records. By leveraging event correlations and a soft-margin approach that accounts for local variability, the method identifies characteristic event durations across 1,485 global tide gauge stations, revealing the influence of both local site conditions and …


Driving Into The Past: Road Logs And The History And Geology Of The Eastern Sierra Of California, Char Miller Jan 2026

Driving Into The Past: Road Logs And The History And Geology Of The Eastern Sierra Of California, Char Miller

Eastern Sierra History Journal

Road Logs are a pedagogical tool that geologists use on field trips with their students. Dee Trent's 1982 Road Log, which reproduced in this issue of ESHJ, also functions as a cultural artifact; it demonstrates what was known then, and how that scientific knowledge and the human geography of the region has changed over time.


Road Log For The Natural History Of The Owens Valley And Eastern Sierra Nevada, D. D. Trent Jan 2026

Road Log For The Natural History Of The Owens Valley And Eastern Sierra Nevada, D. D. Trent

Eastern Sierra History Journal

D.D. Trent, who taught Geology at Citrus College in Southern California for many years, developed this 1982 Road Log for his students for use on field trips. It contains many scientific findings and historical insights about the region and he also contributed hand-drawn maps and illustrations to capture their attention. The Road Log is introduced by Char Miller's essay, "Driving into the Past" and then annotated and updated by Prof. Nicole Moore in an article that follows.


D.D. Trent 1982 Natural History Of Owens Valley/Eastern Sierra: Annotations And Updates, Nicole E. Moore Jan 2026

D.D. Trent 1982 Natural History Of Owens Valley/Eastern Sierra: Annotations And Updates, Nicole E. Moore

Eastern Sierra History Journal

Prof. Moore offers some annotations to and updates of D.D. Trent's 1982 Road Log. These revisions are part of the evolution of scientific knowledge and the adaptation of new technologies that enable a deeper understanding of the geology of the Owens Valley and Eastern Sierra. Like Trent, Moore has routinely taken her students up US 395 to explore and assess the region's geological formations.


Last Glacial Maximum And Late Glacial Aeolian Sand Activity, South-Central Indiana, Usa, H. M. Loope, J. L. Antinao, P.R. Hanson, P. M. Jacobs, D. A. Grimley Jan 2026

Last Glacial Maximum And Late Glacial Aeolian Sand Activity, South-Central Indiana, Usa, H. M. Loope, J. L. Antinao, P.R. Hanson, P. M. Jacobs, D. A. Grimley

Conservation and Survey Division: Faculty and Staff Publications

No abstract provided.


Report 17—Revisions To The Articles Of Organization And Procedure Of The Commission On Stratigraphic Nomenclature Of The Americas, Lynn T. Dafoe, Robert B. Macnaughton, Marie-Perre Aubry, Carlton E. Brett, James R. Lehane, Fernando Núñez-Useche, Randall C. Orndorff, Frank Brunton, Lucy E. Edwards, Richard H. Fluegeman, Howard Harper, Robert Matthew Joeckel, Norman P. Lasca, B. H. Tew Jan 2026

Report 17—Revisions To The Articles Of Organization And Procedure Of The Commission On Stratigraphic Nomenclature Of The Americas, Lynn T. Dafoe, Robert B. Macnaughton, Marie-Perre Aubry, Carlton E. Brett, James R. Lehane, Fernando Núñez-Useche, Randall C. Orndorff, Frank Brunton, Lucy E. Edwards, Richard H. Fluegeman, Howard Harper, Robert Matthew Joeckel, Norman P. Lasca, B. H. Tew

Conservation and Survey Division: Faculty and Staff Publications

Several revisions to the Articles of Organization and Procedure for the North American Commission on Stratigraphic Nomenclature have been adopted following the 75th, 79th, and 80th annual meetings of the Commission in 2020, 2024 and 2025, respectively. Of these, the most substantial change was revision of Article III regarding membership composition of the Commission and the addition of new member organizations from Central and South America and the Caribbean region. As a result, the Commission also voted to change its name to be more inclusive of the expanding membership, with approval of the name: Commission on Stratigraphic Nomenclature of the …


Integrated Seismic And Sequence Stratigraphic Analysis Of The Abu Madi Formation, Baltim Field, Nile Delta, Egypt, Nouran Mostafa Eissa, Mostafa Toni, Alhussein Adham Basheer, Amr Talaat, Amir Ismail Jan 2026

Integrated Seismic And Sequence Stratigraphic Analysis Of The Abu Madi Formation, Baltim Field, Nile Delta, Egypt, Nouran Mostafa Eissa, Mostafa Toni, Alhussein Adham Basheer, Amr Talaat, Amir Ismail

Trends in advanced sciences and technology

Despite the economic significance of the Messinian Abu Madi Formation as a primary gas reservoir target in the Nile Delta Basin, a high-resolution, field-scale integration of seismic sequence stratigraphy with quantitative petrophysical characterization remains lacking for the Baltim area. This study addresses this gap by presenting an integrated seismic sequence stratigraphic and petrophysical analysis of the Upper Miocene Abu Madi Formation within the prolific Baltim gas fields, offshore Nile Delta, Egypt. The objectives are to characterize its depositional architecture, delineate reservoir distribution, and assess hydrocarbon potential. The workflow synthesizes well log data from five key wells with a grid of …


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 Jan 2026

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 Jan 2026

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 …


Innovative Methods In Intact Rock Deformation Detection, Ali Abdullah M Alzahrani Jan 2026

Innovative Methods In Intact Rock Deformation Detection, Ali Abdullah M Alzahrani

Doctoral Dissertations

"An accurate assessment of intact rock deformation is imperative in engineering activities carried out either in or above rock masses. However, instruments used for post-peak deformation are easily debonded and cannot record the whole process of post-peak deformation required in the failure modeling of rocks. This dissertation focuses on the investigation of the performance of two non-contact measuring systems (Laser Displacement Sensor (LDS) and Inductive Proximity Sensor (IPS)) compared to the contact type instrument (conventional Strain Gauge System (SGS)) in monitoring intact rock deformations. Subsequently, an IPS was installed in a high-pressure triaxial testing system before investigating its performance in …


An Integrated Approach To Groundwater Management In Northern New Jersey Watersheds, Toritseju Oyen Jan 2026

An Integrated Approach To Groundwater Management In Northern New Jersey Watersheds, Toritseju Oyen

Theses, Dissertations and Culminating Projects

Groundwater deterioration has emerged as a pressing global concern, with widespread observations of declining water quality in various regions. The predominant cause of this deterioration is attributed to anthropogenic activities, which are deeply intertwined with daily human practices that contaminate water resources. Over the decades, many forested and wetland areas have been converted mainly for increased urbanization and industrialization use in northern New Jersey. The region’s watershed, already characterized as a low-yield aquifer, is facing deterioration because of continuous change in land cover. Anthropogenic activities aimed at providing solutions to problems, such as food scarcity, icy roads during the winter …


The Nature And Origin Of The Strodes Creek Member Of The Lexington Limestone, Central Kentucky, Claire J. Mendenhall Jan 2026

The Nature And Origin Of The Strodes Creek Member Of The Lexington Limestone, Central Kentucky, Claire J. Mendenhall

University of Kentucky Master's Theses

The Strodes Creek Member of the Lexington Limestone is a small, unusual member that is largely known for its beds of fragmented and overturned stromatoporoids. The Strodes Creek Member occurs as two distinct stratigraphic bodies, wholly encompassed by the Millersburg Member, which represents a shallow, open-marine, mixed-clastic-carbonate platform, characterized by thin-bedded to nodular, fossiliferous calcarenites and calcirudites interbedded with shale. In contrast to the Millersburg, the Strodes Creek exhibits a lithologic background of dark, organic-rich, calcareous shales with a westward-thickening section of very irregularly bedded, stromatoporoid-rich, fossiliferous calcisiltites (packstones and wackestones). The calcisiltites are commonly associated with hummocky crossbedding, pinch-and-swell …


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 …


Spatiotemporal Dynamics Of Mountain Front Recharge Flow Paths And Their Contribution To Alluvial Aquifer Water Supply, Mikaela Bollag-Miller Jan 2026

Spatiotemporal Dynamics Of Mountain Front Recharge Flow Paths And Their Contribution To Alluvial Aquifer Water Supply, Mikaela Bollag-Miller

Graduate Student Theses, Dissertations, & Professional Papers

Mountain Front Recharge (MFR) is a critical recharge source for alluvial basin aquifers throughout the Intermountain West, yet the spatial and temporal dynamics of distinct recharge pathways remain poorly constrained. This study investigates the seasonal and spatial dynamics of MFR pathways and evaluates their impact on the Missoula Aquifer, a sole-source alluvial aquifer in western Montana, USA. MFR includes both surface-water inflows from mountain areas and Mountain Block Recharge (MBR), the groundwater contribution to the basin aquifer. A valley-scale water balance was employed to estimate first-order contributions and temporal fluctuations of MBR flow paths. A three-layer steady-state MODFLOW groundwater model …