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Full-Text Articles in Physical Sciences and Mathematics

Identifying Phytoremediation Performing Plant Species That Can Be Utilized In The Improvement Of Heavy Metal Contaminated Soils, Ashley Clark*, Samuel Mutiti May 2024

Identifying Phytoremediation Performing Plant Species That Can Be Utilized In The Improvement Of Heavy Metal Contaminated Soils, Ashley Clark*, Samuel Mutiti

Graduate Research Showcase

Heavy metal pollution is a problem associated with industrialization and development. Two major metals that are commonly mined and can enter the environment, which can jeopardize communities’ health, are copper (Cu) and lead (Pb). There are different options for reducing heavy metal pollution in the environment via remediation efforts, including physical, chemical, and biological methods. However, physical and chemical remediation can be costly and labor-intensive, making them unsuitable for regions that do not have the funds to utilize these practices. Biological remediation is a more cost-conservative practice that has been shown in many studies to be effective in the gradual …


Optimization Of Xrf Experimental Protocol For Bruker Picofox, Tyler Ashcraft May 2024

Optimization Of Xrf Experimental Protocol For Bruker Picofox, Tyler Ashcraft

Undergraduate Honors Theses

The research performed was to improve the precision and accuracy of sample measurements made with the Bruker Picofox X-ray fluorescence spectrometer. The initial method of sample preparation using a 10 μL drop spotted onto an acrylic plate and then drying in an oven at 80˚C produced inconsistent results even when processing replicates or the same sample multiples times. Multiple experiments were conducted to determine the effects of different sample preparation conditions on the resulting accuracy. The conditions tested were drop size, plate composition, and drying temperature. For each experiment an internal standard (gallium) was used at concentrations similar to that …


Comparison Of The Fluorescence Of Bulk Cadmium Sulfide And Cadmium Sulfide Nanoparticles, Jacob Goranson May 2024

Comparison Of The Fluorescence Of Bulk Cadmium Sulfide And Cadmium Sulfide Nanoparticles, Jacob Goranson

Celebrating Scholarship and Creativity Day (2018-)

The fluorescence of bulk cadmium sulfide and cadmium sulfide nanoparticles were compared. This was done using an 800-nm, unamplified Ti:sapphire laser producing 50-fs pulses. The pulses were frequency doubled using a beta barium borate (BBO) crystal. The 400-nm beam was used to induce fluorescence in the nanoparticles, while the original 800-nm beam was used to induce fluorescence in the bulk CdS by two-photon absorption. The bulk CdS showed a single fluorescent peak at 523 nm. The nanoparticles showed fluorescence at various wavelengths across the visible spectrum. In general, the nanoparticles showed a broad fluorescent spectrum between 500 nm and 750 …


A Realist Interpretation Of Unitarity In Quantum Gravity, Indrajit Sen, Stephon Alexander, Justin Dressel May 2024

A Realist Interpretation Of Unitarity In Quantum Gravity, Indrajit Sen, Stephon Alexander, Justin Dressel

Mathematics, Physics, and Computer Science Faculty Articles and Research

Unitarity is a difficult concept to implement in canonical quantum gravity because of state non-normalisability and the problem of time. We take a realist approach based on pilot-wave theory to address this issue in the Ashtekar formulation of the Wheeler–DeWitt equation. We use the postulate of a definite configuration in the theory to define a global time for the gravitational-fermionic system recently discussed in Alexander et al (2022 Phys. Rev. D 106 106012), by parameterising a variation of a Weyl-spinor that depends on the Kodama state. The total Hamiltonian constraint yields a time-dependent Schrodinger equation, without semi-classical approximations, which we …


Peace With Painful Memories, Mona Muzammil, Muzammil Arshad, Washain Muzammil May 2024

Peace With Painful Memories, Mona Muzammil, Muzammil Arshad, Washain Muzammil

Chemistry Faculty Publications and Presentations

This Book helps you identify and heal from childhood emotional neglect so you can be more connected and emotionally present in your life.

Do you sometimes feel like you’re just going through the motions in life? Do you often act like you’re fine when you secretly feel lonely and disconnected? Perhaps you have a good life and yet somehow, it’s not enough to make you happy. Or perhaps you drink too much, eat too much, or risk too much to feel something good. If so, you are not alone and you may be suffering from emotional neglect.

Are you one …


Star-Based Reachability Analysis Of Binary Neural Networks On Continuous Input, Mykhailo Ivashchenko May 2024

Star-Based Reachability Analysis Of Binary Neural Networks On Continuous Input, Mykhailo Ivashchenko

Department of Computer Science and Engineering: Dissertations, Theses, and Student Research

Deep Neural Networks (DNNs) have become a popular instrument for solving various real-world problems. DNNs’ sophisticated structure allows them to learn complex representations and features. However, architecture specifics and floating-point number usage result in increased computational operations complexity. For this reason, a more lightweight type of neural networks is widely used when it comes to edge devices, such as microcomputers or microcontrollers – Binary Neural Networks (BNNs). Like other DNNs, BNNs are vulnerable to adversarial attacks; even a small perturbation to the input set may lead to an errant output. Unfortunately, only a few approaches have been proposed for verifying …


Can Ai Become An Information Literacy Ally? A Survey Of Library Instructor Perspectives On Chatgpt, Melissa S. Del Castillo, Hope Y. Kelly May 2024

Can Ai Become An Information Literacy Ally? A Survey Of Library Instructor Perspectives On Chatgpt, Melissa S. Del Castillo, Hope Y. Kelly

Works of the FIU Libraries

Libraries can play a role in navigating the AI era by integrating these tools into information literacy (IL) programs. To implement generative AI tools like ChatGPT effectively, it is important to understand the attitudes of library professionals involved in IL instruction toward this tool and their intention to use it for instruction. This study explored perceptions of ChatGPT using survey data that included acceptance factors and potential uses derived from the emerging literature. While some librarians saw potential, others found it too unreliable to be useful; yet the vast majority imagined utilizing the tool in the future.


An Improved Bayesian Pick-The-Winner (Ibpw) Design For Randomized Phase Ii Clinical Trials, Wanni Lei, Maosen Peng, Xi K. Zhou May 2024

An Improved Bayesian Pick-The-Winner (Ibpw) Design For Randomized Phase Ii Clinical Trials, Wanni Lei, Maosen Peng, Xi K. Zhou

COBRA Preprint Series

Phase II clinical trials play a pivotal role in drug development by screening a large number of drug candidates to identify those with promising preliminary efficacy for phase III testing. Trial designs that enable efficient decision-making with small sample sizes and early futility stopping while controlling for type I and II errors in hypothesis testing, such as Simon’s two-stage design, are preferred. Randomized multi-arm trials are increasingly used in phase II settings to overcome the limitations associated with using historical controls as the reference. However, how to effectively balance efficiency and accurate decision-making continues to be an important research topic. …


Final Repository Screening Report, Pioneer Technical Services, Inc. May 2024

Final Repository Screening Report, Pioneer Technical Services, Inc.

Silver Bow Creek/Butte Area Superfund Site

No abstract provided.


Final Butte Priority Soils Operable Unit Repository Screening Report, Pioneer Technical Services, Inc. May 2024

Final Butte Priority Soils Operable Unit Repository Screening Report, Pioneer Technical Services, Inc.

Silver Bow Creek/Butte Area Superfund Site

No abstract provided.


A Little Loud And A Little Alone: A Phenomenology Of Leadership Identity Construction Among Women In Higher Education Technology, Amy Barry May 2024

A Little Loud And A Little Alone: A Phenomenology Of Leadership Identity Construction Among Women In Higher Education Technology, Amy Barry

Department of Teaching, Learning, and Teacher Education: Dissertations, Theses, and Student Research

This qualitative study is an exploration of how women in higher education information technology (IT) positions navigate constructing their leadership identities. This includes the messy, personal, internal identity work that occurs prior to claiming their leadership identities on the public stage, followed by an examination of what the experience of attempting to claim and negotiate a leadership identity is like in the social context of their organizations. This educational and sociological study employs an Interpretative Phenomenological Analysis approach with a series of three interviews per participant that allowed the researcher to deeply explore the personal identity experiences of participants. Findings …


Development Of An Enhanced Sampling Workflow To Accelerate Molecular Docking With Sparse Biophysical Information, Zachary Stichter May 2024

Development Of An Enhanced Sampling Workflow To Accelerate Molecular Docking With Sparse Biophysical Information, Zachary Stichter

Masters Theses & Specialist Projects

Rapid docking of flexible biological macromolecules remains a significant open challenge in protein structure determination. While rigid docking is relatively simple with toolkits such as TagDock, a key obstacle to rapid flexible docking is the complexity and roughness of the free energy surface associated with protein conformational motion (often termed the many-minima problem), meaning conventional molecular dynamics methods do not effectively sample protein conformations near the interaction complex in accessible timescales. Methods such as metadynamics and replica exchange molecular dynamics exist to ameliorate this obstacle, yet these methods use nonphysical biases or random swaps to enhance sampling. In contrast, high …


On The Feasibility Of Simple Transformer For Dynamic Graph Modeling, Yuxia Wu, Yuan Fang, Lizi Liao May 2024

On The Feasibility Of Simple Transformer For Dynamic Graph Modeling, Yuxia Wu, Yuan Fang, Lizi Liao

Research Collection School Of Computing and Information Systems

Dynamic graph modeling is crucial for understanding complex structures in web graphs, spanning applications in social networks, recommender systems, and more. Most existing methods primarily emphasize structural dependencies and their temporal changes. However, these approaches often overlook detailed temporal aspects or struggle with long-term dependencies. Furthermore, many solutions overly complicate the process by emphasizing intricate module designs to capture dynamic evolutions. In this work, we harness the strength of the Transformer’s self-attention mechanism, known for adeptly handling long-range dependencies in sequence modeling. Our approach offers a simple Transformer model, called SimpleDyG, tailored for dynamic graph modeling without complex modifications. We …


Why Evidence-Based Hope Is Crucial To Salish Sea Recovery And Beyond, Dr. Elin Kelsey, Ginny Broadhurst May 2024

Why Evidence-Based Hope Is Crucial To Salish Sea Recovery And Beyond, Dr. Elin Kelsey, Ginny Broadhurst

Institute Publications

In April 2023 and March 2024, the Salish Sea Institute engaged hope scholar and thought-leader Elin Kelsey, for events with the common theme of sharing information about evidence-based hope and helping the audience apply that thinking to combat the pervasive doom and gloom narrative that persists about climate change and the environment in general.

The first event was a 2 ½ day Hope for the Salish Sea (HSS) intensive environmental leadership workshop specifically co-designed and led by Elin, Ginny Broadhurst, Director of the Salish Sea Institute, and Mavis Underwood of Tsawout Community, WSANEC Nation. The Salish Sea Institute also organized …


Academic Literature Review In Age Of Ai And Large Language Models​, Aaron Tay May 2024

Academic Literature Review In Age Of Ai And Large Language Models​, Aaron Tay

Research Collection Library

Explore the evolving landscape of academic research with a focus on open data and AI advancements, particularly in natural language processing. Join us for a practical presentation on leveraging emerging tools for literature review. Discover platforms like Connected Papers, ResearchRabbit, and Litmaps, offering paper exploration and recommendations based on initial 'seed papers.' Dive into AI-enhanced search engines like Elicit, Scispace, Semantic Scholar, and Scite.ai, powered by Large Language Models such as BERT and GPT. Learn about the latest developments, strengths, and weaknesses of these tools, and how they reshape literature review methods, from tool selection to query input techniques.


Draft Final 2023 Bpsou Subdrain Data Summary Report (Dsr), Pioneer Technical Services, Inc. May 2024

Draft Final 2023 Bpsou Subdrain Data Summary Report (Dsr), Pioneer Technical Services, Inc.

Silver Bow Creek/Butte Area Superfund Site

No abstract provided.


Analyzing Atmospheric Gravity Waves Over Antarctica And Visualizing Machine Learning Data, Anastasia N. Brown May 2024

Analyzing Atmospheric Gravity Waves Over Antarctica And Visualizing Machine Learning Data, Anastasia N. Brown

Physics Capstone Projects

In an effort to streamline the identification of "clean" windows of airglow images in all sky imager data for the ANGWIN experiment, we have developed a Light Gradient Boosted Machine (LightGBM) learning algorithm that sorts "clean" (marked as 0) wave images from "obscured" (marked as 1) images. These "clean" windows are then processed and undergo FFT-spectrum analysis. We have already successfully created LightGBM models that accurately sort through images taken at the Davis, McMurdo, and Halley research stations in Antarctica. Imager data from the Davis and McMurdo station has been fully processed from the years 2012 to 2022 with clean …


Life On The Edge: The Cambrian Marine Realm And Oxygenation, Sara Pruss, Benjamin C. Gill May 2024

Life On The Edge: The Cambrian Marine Realm And Oxygenation, Sara Pruss, Benjamin C. Gill

Geosciences: Faculty Publications

The beginning of the Phanerozoic saw two biological events that set the stage for all life that was to come: (a) the Cambrian Explosion (the appearance of most marine invertebrate phyla) and (b) the Great Ordovician Biodiversification Event (GOBE), the subsequent substantial accumulation of marine biodiversity. Here, we examine the current state of understanding of marine environments and ecosystems from the late Ediacaran through the Early Ordovician, which spans this biologically important interval. Through a compilation and review of the existing geochemical, mineralogical, sedimentological, and fossil records, we argue that this interval was one of sustained low and variable marine …


Year-Round Co2 Emissions From The Drawdown Area Of A Tropical Reservoir: Strong Seasonal And Spatial Variation, Ícaro Barbosa, José R. Paranaíba, Sebastian Sobek, Sarian Kosten, Rafael M. Almeida, Vitor Duque, Natália Mendonça, Nathan Barros, Raquel Mendonça May 2024

Year-Round Co2 Emissions From The Drawdown Area Of A Tropical Reservoir: Strong Seasonal And Spatial Variation, Ícaro Barbosa, José R. Paranaíba, Sebastian Sobek, Sarian Kosten, Rafael M. Almeida, Vitor Duque, Natália Mendonça, Nathan Barros, Raquel Mendonça

School of Earth, Environmental, and Marine Sciences Faculty Publications and Presentations

Highlights

  • Drawdown areas emitted 80% of reservoir CO2 with just 1/5 area.

  • Emissions from reservoir shorelines near forests were greater than from areas near grassland.

  • CO2 emissions increase with the distance from the water.

  • Estimates of reservoir drawdown CO2 flux vary by ∼ 300 % across the seasons examined here.

  • There was no discernible difference in CO2 emissions between day and night-time.

  • A significant increase in CO2 fluxes was observed 30 min after a rewetting event.

Abstract

A growing body of literature points to drawdown areas as important sources of atmospheric CO2 within reservoirs. Yet seasonal and temporal patterns of …


Skimming Genomes For Systematics And Dna Barcodes Of Corals, Andrea M. Quattrini, Luke J. Mccartin, Erin E. Easton, Jeremy Horowitz, Herman H. Wirshing, Hailey Bowers, Kenneth Mitchell, María Del P. González-García, Makiri Sei, Catherine S. Mcfadden May 2024

Skimming Genomes For Systematics And Dna Barcodes Of Corals, Andrea M. Quattrini, Luke J. Mccartin, Erin E. Easton, Jeremy Horowitz, Herman H. Wirshing, Hailey Bowers, Kenneth Mitchell, María Del P. González-García, Makiri Sei, Catherine S. Mcfadden

School of Earth, Environmental, and Marine Sciences Faculty Publications and Presentations

Numerous genomic methods developed over the past two decades have enabled the discovery and extraction of orthologous loci to help resolve phylogenetic relationships across various taxa and scales. Genome skimming (or low-coverage genome sequencing) is a promising method to not only extract high-copy loci but also 100s to 1000s of phylogenetically informative nuclear loci (e.g., ultraconserved elements [UCEs] and exons) from contemporary and museum samples. The subphylum Anthozoa, including important ecosystem engineers (e.g., stony corals, black corals, anemones, and octocorals) in the marine environment, is in critical need of phylogenetic resolution and thus might benefit from a genome-skimming approach. We …


Local Existence Of Solutions To A Nonlinear Autonomous Pde Model For Population Dynamics With Nonlocal Transport And Competition, Michael R. Lindstrom May 2024

Local Existence Of Solutions To A Nonlinear Autonomous Pde Model For Population Dynamics With Nonlocal Transport And Competition, Michael R. Lindstrom

School of Mathematical and Statistical Sciences Faculty Publications and Presentations

Highlights

  • Partial differential equation models are ubiquitous in applied sciences.

  • A partial differential equation based in ecology is studied for solution existence.

  • Energy methods and convergence analysis lead to local classical solutions.

Abstract

In this paper, we prove that a particular nondegenerate, nonlinear, autonomous parabolic partial differential equation with nonlocal mass transfer admits the local existence of classical solutions. The equation was developed to qualitatively describe temporal changes in population densities over space through accounting for location desirability and fast, long-range travel. Beginning with sufficiently regular initial conditions, through smoothing the PDE and employing energy arguments, we obtain a sequence …


Exploring The Role Of Gender, Race, First-Year College Gpa And Passing Stem Advanced Placement Exams And The Likelihood Of Graduating With A Stem Degree: A Multiple Logistic Regression Analysis, Amar Patel May 2024

Exploring The Role Of Gender, Race, First-Year College Gpa And Passing Stem Advanced Placement Exams And The Likelihood Of Graduating With A Stem Degree: A Multiple Logistic Regression Analysis, Amar Patel

Masters Theses & Specialist Projects

Science, Technology, Engineering, and Mathematics (STEM) careers are projected to grow beyond the normal pace of job growth (Bureau of Labor Statistics, 2021). Many of these careers will require degrees in STEM fields, but, currently, there is a significant underrepresentation of Blacks and females in both STEM degree programs and careers. The purpose of the current quantitative study was to explore the strength of the association between AP Exams, first-year GPA, race, and gender in science achievement. Research Question 1 investigated the relationship between taking AP Exams and the time taken to graduate. For students who took an AP Exam, …


Cultural Immersion In Gaming: Ethiopian Influences In Horizon Forbidden West, Henoch Tilahun May 2024

Cultural Immersion In Gaming: Ethiopian Influences In Horizon Forbidden West, Henoch Tilahun

ART 108: Introduction to Games Studies

This paper examines the immersive incorporation of Ethiopian culture in the video game "Horizon Forbidden West," focusing on visual, narrative, and thematic themes. It explains how the game represents Ethiopian legacy and custom by examining architectural design, landscape portrayal, mythological integration, and character representation. The paper uses different academic works and gaming articles and emphasizes the game's ability to inspire empathy, curiosity, and enthusiasm for cultural diversity, as well as cross-cultural appreciation and understanding. It also investigates the importance of ethical and responsible game production approaches in ensuring accurate cultural portrayal. Finally, this paper examines the transformative power of cultural …


Scientific Frontiers In Game Studies, Prthvi Kapilavai May 2024

Scientific Frontiers In Game Studies, Prthvi Kapilavai

ART 108: Introduction to Games Studies

Video game studies as a dynamic field has benefited from this synthesis of the scientific method and critical theories that, together, enrich our understanding of video games as both technological artifacts and cultural products.(Girina and Jung, 2019). More than a mere shadow-boxing between disciplinary echo chambers, this kind of integration enriches our understanding of video game form and experience while projecting a more informed path forward into game design and game scholarship. It demonstrates how findings from psychology and cognitive science describe or explain video games’ enticement or their potential for learning, and how theories of media from the humanities …


Ai And Advocacy: Maximizing Potential, Minimizing Risk, Matthew Salzano, Nicholas Fung, Ada Lin, Sofia Marchetta, Faith Colombo, Kaylah Davis, John Flynn, Carlos Fuentes, Fion Li, Malar Paavi Muthukumaran, Angelica Paramoshin, Chrisanne Pearce, Vianney Ramos, Charles St. Hilaire, Xi Zheng, Wei Zhuang May 2024

Ai And Advocacy: Maximizing Potential, Minimizing Risk, Matthew Salzano, Nicholas Fung, Ada Lin, Sofia Marchetta, Faith Colombo, Kaylah Davis, John Flynn, Carlos Fuentes, Fion Li, Malar Paavi Muthukumaran, Angelica Paramoshin, Chrisanne Pearce, Vianney Ramos, Charles St. Hilaire, Xi Zheng, Wei Zhuang

School of Communication and Journalism Faculty Publications

New Generative AI tools are revolutionizing writing and communication. This report focuses on AI and advocacy, the act of influencing public policy and resource allocation decisions within political, economic, and social systems and institutions. This report identifies three major opportunities and accompanying risks, plus one strong recommendation for advocates considering using AI. We argue that AI can be useful for advocates, but they must be careful to center human judgment and avoid risks that could distract from their important work or even contribute to societal harms.


Weighted Ehrhart Theory: Extending Stanley's Nonnegativity Theorem, Esme Bajo, Robert Davis, Jesús A. De Loera, Alexey Garber, Sofía Garzón Mora, Katharina Jochemko, Josephine Yu May 2024

Weighted Ehrhart Theory: Extending Stanley's Nonnegativity Theorem, Esme Bajo, Robert Davis, Jesús A. De Loera, Alexey Garber, Sofía Garzón Mora, Katharina Jochemko, Josephine Yu

School of Mathematical and Statistical Sciences Faculty Publications and Presentations

We generalize R. P. Stanley's celebrated theorem that the h∗-polynomial of the Ehrhart series of a rational polytope has nonnegative coefficients and is monotone under containment of polytopes. We show that these results continue to hold for weighted Ehrhart series where lattice points are counted with polynomial weights, as long as the weights are homogeneous polynomials decomposable as sums of products of linear forms that are nonnegative on the polytope. We also show nonnegativity of the h∗-polynomial as a real-valued function for a larger family of weights.

We generalize R. P. Stanley's celebrated theorem that the h ⁎ -polynomial of …


Synthesis Of Thermoresponsive Poly(N-Isopropyl Acrylamide) Based Core-Shell And Hollow Shell Nanogel With Tunable Core And Shell Thickness, Mohamad Hijazi, Molla R. Islam May 2024

Synthesis Of Thermoresponsive Poly(N-Isopropyl Acrylamide) Based Core-Shell And Hollow Shell Nanogel With Tunable Core And Shell Thickness, Mohamad Hijazi, Molla R. Islam

Student Scholar Symposium Abstracts and Posters

Nanogels have emerged as a notably safer and more effective means for drug delivery, primarily due to their adjustable drug-loading capabilities. Hollow-core nanoparticles offer some unique properties that are desirable for drug delivery applications. Initially, silica core nanoparticles were synthesized using the Stöber process at different temperatures where Tetraethoxysilane (TEOS) undergoes hydrolysis in the presence of ethanol and then a condensation reaction to form silica nanoparticles. Scanning Electron Microscopy (SEM) and Optical Microscopy (OM) analysis revealed that the size of silica core particles varied with the synthesis temperature (300 nm at 30°C to 150 at 60°C). The core silica particles …


Bernstein Polynomials Method For Solving Multi-Order Fractional Neutral Pantograph Equations With Error And Stability Analysis, M. H. T. Alshbool May 2024

Bernstein Polynomials Method For Solving Multi-Order Fractional Neutral Pantograph Equations With Error And Stability Analysis, M. H. T. Alshbool

All Works

In this investigation, we present a new method for addressing fractional neutral pantograph problems, utilizing the Bernstein polynomials method. We obtain solutions for the fractional pantograph equations by employing operational matrices of differentiation, derived from fractional derivatives in the Caputo sense applied to Bernstein polynomials. Error analysis, along with Chebyshev algorithms and interpolation nodes, is employed for solution characterization. Both theoretical and practical stability analyses of the method are provided. Demonstrative examples indicate that our proposed techniques occasionally yield exact solutions. We compare the algorithms using several established analytical methods. Our results reveal that our algorithm, based on Bernstein series …


Synthesis Of Gold Nanoparticles Via Pulsed Liquid Ablation For Use In The Photodynamic Therapy Of Bacteria, Justice Ben Yosef May 2024

Synthesis Of Gold Nanoparticles Via Pulsed Liquid Ablation For Use In The Photodynamic Therapy Of Bacteria, Justice Ben Yosef

Masters Theses & Specialist Projects

With the ever-increasing threat of antibiotic resistant bacteria, alternative treatment methods have been developed including photodynamic therapy (PDT). Within the PDT process, photosensitizers are used to generate reactive oxygen species (ROS) and facilitate the cell termination process. This work lays the conceptual foundation for the functionalization of the photosensitizer methylene blue (MB) with gold nanoparticles (AuNPs) and INF-55 as a potential inhibitor of the AcrAB-TolC efflux pump to enhance the effectivity of the PDT process.

AuNPs were synthesized using pulsed laser ablation in an aqueous citrate solution. Both nanosecond and picosecond pulse durations, as well as both 532 nm and …


Volcanic Glass As A Proxy For Paleotopography Suggests New Features In Late-Miocene Oregon, Julian Cohen, John Bershaw, Richard Hugo May 2024

Volcanic Glass As A Proxy For Paleotopography Suggests New Features In Late-Miocene Oregon, Julian Cohen, John Bershaw, Richard Hugo

Geology Faculty Publications and Presentations

Volcanic glass has been used extensively as a paleoaltimeter. Deuterium (2H) concentrations in glass have been found to be stable over geologic timescales, making δ2H (also known as δD) a reliable proxy for ancient water chemistry. However, continued work revolves around better understanding how different factors affect preserved water in volcanic ash. Here, we analyze δD in the Rattlesnake Tuff (RST), a widespread ca. 7 Ma ash-flow tuff, and create a paleoisoscape to assess variations in δD across Oregon during that time. To this end, 16 ash samples were collected across central and eastern Oregon from …