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Full-Text Articles in Geochemistry

Subaqueous Carbonate Speleothems As Paleotemperature Archives – Clumped Isotope Thermometry And Stable Isotope Compositions Of Inclusion-Hosted Water, Attila Demeny, Ágnes Berentés, László Rinyu, Ivett Kovács, Gergely Surányi, Magdolna Virág Feb 2024

Subaqueous Carbonate Speleothems As Paleotemperature Archives – Clumped Isotope Thermometry And Stable Isotope Compositions Of Inclusion-Hosted Water, Attila Demeny, Ágnes Berentés, László Rinyu, Ivett Kovács, Gergely Surányi, Magdolna Virág

International Journal of Speleology

Clumped isotope measurements of carbonates and stable isotope analyses of water trapped in fluid inclusions are both promising techniques to determine carbonate formation temperatures. Cave-hosted carbonate deposits (speleothems) are excellent targets for such studies, but kinetic fractionations and diagenetic influences frequently deteriorate the temperature data obtained from these methods. However, subaqueous carbonate deposits may provide reliable data, as kinetic fractionations are less significant in underwater environments. In this study, subaqueous speleothems, whose formation temperatures were directly measured in the water, were investigated. Additionally, temperatures calculated from the oxygen isotope fractionations between calcite and fluid inclusion-hosted water were compared with clumped …


Re-Evaluating Missouri’S Strategic Element Potential: A Geochemical Study Of The Mesoproterozoic Fe-Cu-Co-Ree Deposits In Southeast Missouri, Usa, Brandon James Sullivan Jan 2024

Re-Evaluating Missouri’S Strategic Element Potential: A Geochemical Study Of The Mesoproterozoic Fe-Cu-Co-Ree Deposits In Southeast Missouri, Usa, Brandon James Sullivan

Doctoral Dissertations

"Iron-oxide-copper-gold (IOCG) deposits are poorly understood mineral systems. For example, we do not know why Cu- and Co-rich IOCG deposits typically occur proximal to Fe ore deposits that are notably Cu and Co-poor, such as Iron Oxide Apatite (IOA) deposits. To better understand the formation of IOA and IOCG deposits in Missouri, USA, this PhD thesis examines the genesis of the Kratz Spring IOA and the Boss Central Dome IOCG deposits. This study presents the first constraints on formation conditions and fluid sources in the studied deposits using integrated petrographic, mineral composition, and Fe isotope analyses of oxide minerals. Observations …


Potentially Massive And Global Non-Pyrogenic Production Of Condensed "Black" Carbon Through Biomass Oxidation, Aleksandar I. Goranov, Hongmei Chen, Jianshu Duan, Satish C. B. Myneni, Patrick G. Hatcher Jan 2024

Potentially Massive And Global Non-Pyrogenic Production Of Condensed "Black" Carbon Through Biomass Oxidation, Aleksandar I. Goranov, Hongmei Chen, Jianshu Duan, Satish C. B. Myneni, Patrick G. Hatcher

Chemistry & Biochemistry Faculty Publications

With the increased occurrences of wildfires worldwide, there has been an increase in scientific interest surrounding the chemistry of fire-derived "black" carbon (BC). Traditionally, wildfire research has assumed that condensed aromatic carbon (ConAC) is exclusively produced via combustion, and thus, ConAC is equated to BC. However, the lack of correlations between ConAC in soils or rivers and wildfire history suggests that ConAC may be produced non-pyrogenically. Here, we show quantitative evidence that this occurs during the oxidation of biomass with environmentally ubiquitous hydroxyl radicals. Pine wood boards exposed to iron nails and natural weather conditions for 12 years yielded a …


Reducing Food Scarcity: The Benefits Of Urban Farming, S.A. Claudell, Emilio Mejia Dec 2023

Reducing Food Scarcity: The Benefits Of Urban Farming, S.A. Claudell, Emilio Mejia

Journal of Nonprofit Innovation

Urban farming can enhance the lives of communities and help reduce food scarcity. This paper presents a conceptual prototype of an efficient urban farming community that can be scaled for a single apartment building or an entire community across all global geoeconomics regions, including densely populated cities and rural, developing towns and communities. When deployed in coordination with smart crop choices, local farm support, and efficient transportation then the result isn’t just sustainability, but also increasing fresh produce accessibility, optimizing nutritional value, eliminating the use of ‘forever chemicals’, reducing transportation costs, and fostering global environmental benefits.

Imagine Doris, who is …


Reverse Pseudo-Gours: A New Sub-Type Of Folia Observed In The Nerja Cave (Se Spain), Cristina Liñán Baena, Concepción Jiménez De Cisneros, Yolanda Del Rosal, Paolo Forti Dec 2023

Reverse Pseudo-Gours: A New Sub-Type Of Folia Observed In The Nerja Cave (Se Spain), Cristina Liñán Baena, Concepción Jiménez De Cisneros, Yolanda Del Rosal, Paolo Forti

International Journal of Speleology

A new sub-type of folia named “reverse pseudo-gour” has been observed and described in the Nerja Cave, southern Spain. It consists of fairly vertical, thin barriers (about 5 mm high and 2 mm thick) that develop on the underside of a sub-horizontal surface (shelfstone) and grow in the opposite direction to normal gours (rimstone dams), generating sinuous shapes. Their mineral composition is essentially calcium carbonate, although globular aggregates composed of clay and phosphate minerals have also been identified. The genesis and evolution of these reverse pseudo-gours occur just at the air-water interface and are controlled by (1) the sub-horizontality of …


Environmental Fate Of Sulfur In Sulphur Creek, Valles Caldera, Nm: Implications For Metal Transport And Water Quality, Daniel Lavery Dec 2023

Environmental Fate Of Sulfur In Sulphur Creek, Valles Caldera, Nm: Implications For Metal Transport And Water Quality, Daniel Lavery

Earth and Planetary Sciences ETDs

The 1.2 Ma Valles Caldera in north-central New Mexico hosts a young igneous volcanic hydrothermal system after the model proposed in Goff and Janik (2000). The Sulphur Springs area within Valles Caldera is an acid-sulfate area typical of this model, discharging acidic waters (pH 1.5-3) formed by oxidation of magmatic H2S at the surface. We report on samples obtained from springs and streams collected between October 2021 and May 2023 in the Sulphur Creek and Alamo watersheds. Sulphur Creek receives input from Sulphur Springs and exhibits low pH (2-4) and high concentrations of Al (≤110 mg/L), Fe (≤60 …


Wonderstone And Its Connection To Liesegang, Microbes, And Beyond, Haden S. Mandery Dec 2023

Wonderstone And Its Connection To Liesegang, Microbes, And Beyond, Haden S. Mandery

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

In the western and southwestern United States, the term wonderstone is used to describe volcanic, volcaniclastic, and sedimentary rocks with variegated banding produced by iron oxide mineralization or staining. This iron oxide mineralization is typically described as Liesegang banding. In this paper I will (1) test if the banding in wonderstone follows the spacing and width laws characteristic of Liesegang, (2) identify the source of iron that ultimately precipitated in the bands, and (3) examine the role that microbes played in the formation of the mineralization in these rocks. I conclude that the iron oxide mineralization is not Liesegang banding. …


Characterizing Silicate Materials Via Raman Spectroscopy And Machine Learning: Implications For Novel Approaches To Studying Melt Dynamics, Blake O. Ladouceur Dec 2023

Characterizing Silicate Materials Via Raman Spectroscopy And Machine Learning: Implications For Novel Approaches To Studying Melt Dynamics, Blake O. Ladouceur

Doctoral Dissertations

Silicate melt characteristics impose dramatic influence over igneous processes that operate, or have operated on, differentiated bodies: such as the Earth and Mars. Current understanding of these melt properties, such as composition, primarily comes from investigations on their volcanic byproducts. Therefore, it is imperative to innovate on modalities capable of constraining melt information in environments where a reliance on laboratory methods is severed. Recent investigations have turned to Raman Spectroscopy and amorphous volcanics as a suitable pairing for exploring these ideas. Silicate glasses are a proxy for igneous melts; and Raman spectroscopy is a robust analytical technique capable of operating …


Enhancing Our Understanding Of Ancient Oceans Through The Investigation Of Molybdenum Behavior Under Sulfidic Conditions, Rachel Faye Phillips Dec 2023

Enhancing Our Understanding Of Ancient Oceans Through The Investigation Of Molybdenum Behavior Under Sulfidic Conditions, Rachel Faye Phillips

Open Access Theses & Dissertations

The most abundant trace metal in the ocean today, molybdenum (Mo), exhibits distinct behavior in oxygenated water, where it remains predominantly dissolved, compared to euxinic (i.e., oxygen-free and sulfidic) water, in which it is sequestered into the sediment. This dissimilar behavior allows us to use Mo concentrations and isotopic compositions in sediment to reconstruct marine oxygenation conditions throughout geologic history. However, Mo sequestration mechanisms under euxinic conditions remain unresolved, which limits the accuracy and precision of reconstructions made using Mo signatures in the rock record. For my doctoral research, I experimentally investigated abiotic and biotic Mo sequestration mechanisms under various …


Geospatial Analysis Of Weathering And Recession On Architectural Limestone At The 1891 Powerhouse/Icehouse In Eureka Springs, Arkansas, Stuart Bruce Wright Dec 2023

Geospatial Analysis Of Weathering And Recession On Architectural Limestone At The 1891 Powerhouse/Icehouse In Eureka Springs, Arkansas, Stuart Bruce Wright

Graduate Theses and Dissertations

The objective of this study of the architectural limestone of the 1891 Powerhouse/Icehouse in Eureka Springs, Arkansas was to analyze the environmental factors that influenced the deterioration and surface recession of this historical stone structure. The focus of this research was to examine and establish a baseline study that may assist in future monitoring and documentation of this historic limestone structure on stone weathering. A replicable methodology was specifically created toward this baseline research in hopes that it represented a solid baseline study. Observations and data analyses revealed the relationship between the architectural limestone building structure and the dominating recession …


Preliminary Assessment For Critical Minerals In The Terlingua Quicksilver District, Texas And Tres Marias Mine, Chihuahua, Mexico, Eduardo Lee Zuniga Dec 2023

Preliminary Assessment For Critical Minerals In The Terlingua Quicksilver District, Texas And Tres Marias Mine, Chihuahua, Mexico, Eduardo Lee Zuniga

Open Access Theses & Dissertations

The Terlingua Quicksilver district was discovered around the 1880s and was a mercury producing district from 1900 through 1946. The most productive years were during World War one and two. From 1900-1946 the Terlingua Quicksilver District (TQD) produced 150,000 flasks; 80% came from three mines: the Rainbow-Chisos, Mariposa, and Study Butte mines. The structural controls of the Mercury mineralization within these mines are breccia pipes and fractures, often located near igneous intrusions. This study will assess the potential for Critical Minerals and Rare Earth Elements in the Terlingua Quicksilver District. Fifty-five samples have been collected and analyzed for forty-four different …


Landscape/Atmosphere Interactions And Carbon-Dioxide Dynamics In The Great Onyx Groundwater Basin, Mammoth Cave National Park, Kentucky, Meghan Raines Dec 2023

Landscape/Atmosphere Interactions And Carbon-Dioxide Dynamics In The Great Onyx Groundwater Basin, Mammoth Cave National Park, Kentucky, Meghan Raines

Masters Theses & Specialist Projects

An increase in atmospheric CO2 since the Industrial Revolution has altered rates of global climate change and has motivated a need to better quantify the flux of carbon between Earth’s reservoirs. Attempts to quantify the exchange of atmospheric carbon between sources and sinks have led to an increasing interest in the terrestrial landscape, including the continental carbon sink associated with carbonate-mineral dissolution. This research sought to better inform an understanding of karst landscapes and their relationship with global climate change through carbon cycling. The study utilized high-resolution data collection of pH, temperature, and specific conductance of waters in the Cascade …


Volcanic Diffuse Volatile Emissions Tracked By Plant Responses Detectable From Space, Robert R. Bogue, Peter M. J. Douglas, Joshua B. Fisher, John Stix Nov 2023

Volcanic Diffuse Volatile Emissions Tracked By Plant Responses Detectable From Space, Robert R. Bogue, Peter M. J. Douglas, Joshua B. Fisher, John Stix

Biology, Chemistry, and Environmental Sciences Faculty Articles and Research

Volcanic volatile emissions provide information about volcanic unrest but are difficult to detect with satellites. Volcanic degassing affects plants by elevating local CO2 and H2O concentrations, which may increase photosynthesis. Satellites can detect plant health, or a reaction to photosynthesis, through a Normalized Difference Vegetation Index (NDVI). This can act as a potential proxy for detecting changes in volcanic volatile emissions from space. We tested this method by analyzing 185 Landsat 5 and 8 images of the Tern Lake thermal area (TLTA) in northeast Yellowstone caldera from 1984 to 2022. We compared the NDVI values of the thermal area with …


Labile Dissolved Nickel (Ni) Concentrations In The North Pacific, Calyn M. Crawford Oct 2023

Labile Dissolved Nickel (Ni) Concentrations In The North Pacific, Calyn M. Crawford

USF Tampa Graduate Theses and Dissertations

Nickel (Ni) is an important micronutrient for phytoplankton and bacteria that serves as a required co-factor in several metalloenzymes. Despite these known biological uses, total dissolved Ni concentrations remain elevated in global surface waters, in contrast to the surface depletion commonly observed for macronutrients and other nutrient-type trace elements. A prevailing hypothesis for the muted depletion of dissolved Ni concentrations in surface waters is that dissolved Ni in seawater is not in a bioavailable form. The chemical lability of Ni in seawater provides insight into Ni speciation and bioavailability, but few measurements have been made in the open ocean to …


More Than Energy: Coal As A Mineral Resource, University Of North Dakota. Energy And Environmental Research Center Oct 2023

More Than Energy: Coal As A Mineral Resource, University Of North Dakota. Energy And Environmental Research Center

EERC Brochures and Fact Sheets

Brochure on Carbon Ore, Rare Earth, and Critical Minerals (CORE-CM) Initiative, an Energy & Environmental Research Center (EERC) and U.S. Department of Energy (DOE) project. Explores the benefits of utilizing lignite coal from the Williston Basin.


Core-Cm Williston Basin Carbon Ore, Rare Earth, And Critical Minerals, University Of North Dakota. Energy And Environmental Research Center Oct 2023

Core-Cm Williston Basin Carbon Ore, Rare Earth, And Critical Minerals, University Of North Dakota. Energy And Environmental Research Center

EERC Brochures and Fact Sheets

Fact sheet on the Carbon Ore, Rare Earth and Critical Minerals (CORE-CM) Initiative, an Energy & Environmental Research Center (EERC) and U.S. Department of Energy (DOE) project. Includes information on the importance of critical minerals and utilizing lignite from the Williston Basin.


Shared Roots: A Geochemical Investigation Of Basaltic Andesites To Understand Magmatic Cogenesis At The Middle Sister And South Sister Volcanoes, Central Oregon, Sean Francis Halstead Oct 2023

Shared Roots: A Geochemical Investigation Of Basaltic Andesites To Understand Magmatic Cogenesis At The Middle Sister And South Sister Volcanoes, Central Oregon, Sean Francis Halstead

WWU Honors College Senior Projects

The Middle Sister and South Sister volcanoes, near Bend, Oregon, are overlapping, active Cascade Arc stratovolcanoes which share a complex, contemporaneous eruptive history. This history is characterized by an extreme compositional diversity of lavas erupted in alternating phases of high activity from one neighboring volcano to the other, with both vents producing material ranging from basaltic andesite to rhyolite. This system is understood to be predominantly fed by basaltic andesites fractionated from partial mantle melts within the lower crust, but magma compositions are additionally impacted by mixing, assimilation, and crustal contamination while in transit to the surface. Thus, the subterranean …


North Bergen Outcrop Field And Geochemical Data, Jane L. Alexander, Sean T. Thatcher, Jay Tobon, Victoria Rivelli Sep 2023

North Bergen Outcrop Field And Geochemical Data, Jane L. Alexander, Sean T. Thatcher, Jay Tobon, Victoria Rivelli

Publications and Research

This file contains the data collected on an outcrop of the Stockton Formation in North Bergen, NJ. It contains field observations, mineralogy and geochemical data for major, trace and rare earth elements.


Hydrothermal Carbonization Of Biomass Wastes: Sustainability And Geochemistry, Michael A. Kruge, Teresa A. Centeno, Alvaro Amado-Fierro, José Manuel González-Lafuente, Ruben Forjan-Castro, José Luis Gallego Sep 2023

Hydrothermal Carbonization Of Biomass Wastes: Sustainability And Geochemistry, Michael A. Kruge, Teresa A. Centeno, Alvaro Amado-Fierro, José Manuel González-Lafuente, Ruben Forjan-Castro, José Luis Gallego

Department of Earth and Environmental Studies Faculty Scholarship and Creative Works

Introduction. To reduce the stream of solid waste going to landfills, innovative means for beneficial use are essential. The diversity and volume of organic wastes pose singular problems and opportunities for recovery and circularity. Common processes for organics include conversion to biofuels and carbonization to biochar, typically done by torrefaction (dry pyrolysis). Research on biochar explores its potential as pollutant adsorbent, agricultural or polluted soil amendment, biofuel (directly or as feedstock), and for carbon sequestration (Ighalo et al., 2022; Cavali et al., 2023). Recently, other processes at lower temperatures such as hydrothermal carbonization (HTC) offer new possibilities (Seshadri et al., …


Investigating Mercer's Paradox: A 10be Chronology Of Moraines Deposited During The Last Glaciation At Soda Lake, Wind River Range, Wyoming, U.S.A., Lauren M. Woods Aug 2023

Investigating Mercer's Paradox: A 10be Chronology Of Moraines Deposited During The Last Glaciation At Soda Lake, Wind River Range, Wyoming, U.S.A., Lauren M. Woods

Electronic Theses and Dissertations

Here I use geomorphic mapping and 10Be surface-exposure dating to address the paradox that lies within the general understanding of the mechanisms driving ice-age climate and glacial cycles. The long-standing and widely accepted Murphy-Milankovitch hypothesis suggests glacial cycles are controlled by the local intensity of summer-time insolation. By this hypothesis, glacier maxima should be achieved at times of low insolation intensity and asynchronously between the polar hemispheres, a pattern which is inconsistent with the glacial geomorphic record. The 10Be chronology I have constructed of moraines at Soda Lake, Wind River Range, Wyoming, U.S.A. shows nine glacial advances to …


The Upper Ocean At The End Of An Ice Age: Using Proxies In Benthic Foraminifera To Investigate Intermediate Water Changes During The Last Glacial Termination, Cassandre R. Stirpe Aug 2023

The Upper Ocean At The End Of An Ice Age: Using Proxies In Benthic Foraminifera To Investigate Intermediate Water Changes During The Last Glacial Termination, Cassandre R. Stirpe

Electronic Theses and Dissertations

The ocean is an important component of the global climate system and plays a key role as a storage reservoir for heat and carbon. Under glacial conditions, the ocean sequestered carbon from the atmosphere, contributing to a cooler global climate. During the last glacial termination, that carbon was released back into the atmosphere, but the exact timing and mechanisms of this transfer are still not fully understood. This study examines waters from the intermediate depths of the Southern Ocean to gain insight into deglacial processes. Intermediate waters are capable of reacting to climate change on decadal timescales, making them a …


Utilizing Phylogenetic And Geochemical Techniques To Examine Echinoderms Through Time, Maggie Ryan Limbeck Aug 2023

Utilizing Phylogenetic And Geochemical Techniques To Examine Echinoderms Through Time, Maggie Ryan Limbeck

Doctoral Dissertations

Understanding biotic changes through Earth’s history has been the goal of paleobiology since the inception of the field. Advances in science and technology have progressed allowing us to reassess old questions and new questions that could have not been addressed without these new methods. Echinoderms (sea stars, sea urchins, etc.) appear in the fossil record during the early Cambrian and are still abundant in marine ecosystems today. This persistence through time has made echinoderms model organisms to answer questions about Earth’s past and present. Despite this role as a model organism there are many questions that remain with respect to …


Metagenomic Investigation Of Microbial Dark Carbon Fixation, Viral Interactions, And Horizonal Gene Transfer Within A Convergent Margin Subsurface Ecosystem, Timothy Joseph Rogers Aug 2023

Metagenomic Investigation Of Microbial Dark Carbon Fixation, Viral Interactions, And Horizonal Gene Transfer Within A Convergent Margin Subsurface Ecosystem, Timothy Joseph Rogers

Doctoral Dissertations

Convergent margins are geological regions where two or more tectonic plates collide, and the denser “subducting slab” is pushed beneath the less dense overriding plate. As the slab descends, it devolatilizes under higher temperatures and pressures, allowing dissolved inorganic carbon (DIC) and redox active volatile rich fluids to cycle between the upper crust and Earth’s mantle. These fluids migrate through cracks and fissures in the upper mantle and crust, fueling chemolithoautotrophy-based microbial ecosystems in the subsurface before they are expelled on the surface in the form of hydrothermal seeps and springs. Chemolithoautotrophic ecosystems, such as those in the Costa Rican …


Numerical And Experimental Constraints On Trace Element Fractionation During Lunar Magma Ocean Solidification, Dian Ji Aug 2023

Numerical And Experimental Constraints On Trace Element Fractionation During Lunar Magma Ocean Solidification, Dian Ji

Masters Theses

Traditional lunar magma ocean (LMO) theory suggests the anorthositic lunar crust formed by floating of buoyant plagioclase, one of the major products of LMO solidification, on the surface of LMO. To test this model, after applying experimentally determined LMO solidification sequences, we compared calculated Rare Earth Element (REE) concentrations of lunar plagioclase to plagioclase in Apollo ferroan anorthosites and lunar anorthositic meteorites. Several initial LMO compositions, and lunar-relevant mineral-melt partition coefficient predictive models were tested (where the partition coefficient is the concentration ratio of a specific element between two phases). Compared with plagioclase in the natural samples, modeled plagioclase directly …


A Hybrid Lateral Flow Sand Filter Wastewater Treatment System: An Evaluation On The Treatment And Disposal Capabilities Of A Modified Sand Filter, Harry Mccaskill Iv Aug 2023

A Hybrid Lateral Flow Sand Filter Wastewater Treatment System: An Evaluation On The Treatment And Disposal Capabilities Of A Modified Sand Filter, Harry Mccaskill Iv

<strong> Theses and Dissertations </strong>

Decentralized wastewater treatment exists primarily in suburban and rural areas where centralized treatment is not an option. Traditional on-site treatment systems usually include the use of a septic tank and a drain field. This orthodox method works well when implemented into environments that are accommodating for the infiltration of effluents, and thus allowing for soil treatment. Unfortunately, there are some circumstances that prevent traditional systems from working such as impermeable soil conditions. The Wastewater Treatment System analyzed in this thesis was created to overcome such inhospitable environments. More specifically, this system is catered towards the rural residences of The Alabama …


Thames River Subwatershed Soil, Sediment, Water Data, Justin B. Richardson, Mark J. Butler Jul 2023

Thames River Subwatershed Soil, Sediment, Water Data, Justin B. Richardson, Mark J. Butler

Data and Datasets

Trace element and nutrient data are for riparian soils, suspended sediments, eddy bottom sediments, and river water collected between 2019 and 2020 in the Thames River watershed of Connecticut, USA. Trace elements and nutrients were measured using EPA 3050B digestion method and analyzed by ICP-OES or ICP-MS.


Polygonal Faults In The Austin Chalk: Invariance Of Scale From Mud Cracks To Polygons With Implications Of Structural, Geomorphic And Isotopic Data On Polygonal Fault Geometry And Origin., Kun Shang Jul 2023

Polygonal Faults In The Austin Chalk: Invariance Of Scale From Mud Cracks To Polygons With Implications Of Structural, Geomorphic And Isotopic Data On Polygonal Fault Geometry And Origin., Kun Shang

Earth Sciences Theses and Dissertations

The Cretaceous Austin Chalk contains large numbers of fractures and normal faults whose orientations have been attributed to either regional stresses (e.g., the Balcones fault trend) or, by analogy with the mudrocks, to polygonal faulting resulting from compaction. In this study, we present geomorphic data, field study, and stable isotope data to support that the majority of these faults in North Texas are polygonal. Field-measured fault orientations suggest randomly distributed fault strikes, indicating a polygonal fault structure. Using geomorphologic data (topographic and DEM data) on stream orientations suggests that the polygonal fault patterns are best reflected in the headwater (1st …


Environmental Chemical Analysis Method Optimization And Application To Northwest Cuban Marine Sediment, Thea R. Bartlett Jun 2023

Environmental Chemical Analysis Method Optimization And Application To Northwest Cuban Marine Sediment, Thea R. Bartlett

USF Tampa Graduate Theses and Dissertations

A method for gas chromatography tandem mass spectrometry (GC-MS/MS) in selected reaction monitoring (SRM) mode has been optimized to quantify 250 compounds of a variety of compound classes such as polycyclic aromatic hydrocarbons (PAHs), oxidized PAHs, organochlorinated pesticides, polychlorinated biphenyls, biomarkers (hopanes, steranes, tri-aromatic steroids, and fecal sterols), aliphatic hydrocarbons, and plastic additives. This method was validated based on available QA/QC standards using several environmental samples, both sediment and biota, and standard reference materials. This contaminant-focused method can be used as a forensic geochemistry tool to evaluate oil contamination and other contaminant histories in future research studies. When applied to …


A Typological And Chemical Analysis Of Roman Oil Lamps From Poggio Del Molino, Brandon Tejo Jun 2023

A Typological And Chemical Analysis Of Roman Oil Lamps From Poggio Del Molino, Brandon Tejo

Dissertations, Theses, and Capstone Projects

Terracotta lamps, known to the Romans as lucernae, are small, handheld, often decorated objects which provided ancient people light. To modern researchers, they serve as tools for dating stratigraphy and iconographic studies. Beyond their immediately apparent aesthetic and symbolic value, the chemical compositions of the clay of these lamps reflect their origin. This study complements archaeological typologies with chemometric analyses to describe 16 Late Republican and Imperial Roman lamps recovered from the villa at Poggio del Molino (PdM), Tuscany. These finds were recovered from the 2021 and 2022 PdM excavations. The combined approach of typology with X-ray Diffraction (XRD) …


Untangling The Nature And Timescales Of Magmatic Processes Driving Eruptions At Quiescent Volcanoes: Examples From Momotombo, Nicaragua, And Cumbre Vieja, Canary Islands, Samantha Tramontano Jun 2023

Untangling The Nature And Timescales Of Magmatic Processes Driving Eruptions At Quiescent Volcanoes: Examples From Momotombo, Nicaragua, And Cumbre Vieja, Canary Islands, Samantha Tramontano

Dissertations, Theses, and Capstone Projects

Across all scales of human relationships (i.e. person-to-person, country-to-country, etc.), qualms can take the form of long-standing wars, quick and intense bouts, or petty exchanges. While our understanding of human behavior is ever increasing, reactions and behaviors of self and others may still come as a surprise. Expressions of disagreement can occur suddenly or following years to centuries of accumulated grievances. The solid earth is also a system that behaves (like human emotion) predictably at times and unpredictably at other times. Some volcanoes, a tangible surface expression of solid earth processes, exhibit precursory signals prior to eruption (e.g. the bulging …