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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 2024 Institute for Geological and Geochemical Research, Budapest, Hungary

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 2024 Missouri University of Science and Technology

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 2024 Old Dominion University

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 …


An Experiment To Determine Mineral-Associated Organic Matter Turnover In A Sandy Clay Loam, Samantha Abel 2024 Central Washington University

An Experiment To Determine Mineral-Associated Organic Matter Turnover In A Sandy Clay Loam, Samantha Abel

All Master's Theses

Soil is an important terrestrial carbon sink. Through regenerative land management, which includes minimizing soil disturbance, the carbon content of soil can be raised towards preindustrial levels. This feat requires effectively storing carbon in a natural system that is inclined to cyclicity. The most stable form of soil organic matter is mineral-associated organic matter (MAOM). This carbon labelling experiment was designed to identify short-term CO2 fluxes within the soil-plant-atmosphere system, particularly those related to MAOM turnover in the rhizosphere. Basil (Ocimum basilicum) was planted on a plot at the campus farm at Central Washington University. Another plot …


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

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 2023 Research Institute Nerja Cave and University of Malaga, Spain

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 2023 University of New Mexico - Main Campus

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 2023 University of Nebraska-Lincoln

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 2023 University of Tennessee, Knoxville

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 2023 University of Texas at El Paso

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 2023 University of Arkansas-Fayetteville

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 2023 University of Texas at El Paso

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 2023 Western Kentucky University

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 2023 McGill University

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 2023 University of South Florida

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 2023 University of North Dakota

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 2023 University of North Dakota

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 2023 Western Washington University

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 2023 CUNY College of Staten Island

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 2023 INCAR-CSIC

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., …


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