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Oxygen Speciation In Potassium Silicate And Potassium Aluminosilicate Glasses: Insights From X-Ray Photoelectron Spectroscopy, Ryan Sawyer 2022 The University of Western Ontario

Oxygen Speciation In Potassium Silicate And Potassium Aluminosilicate Glasses: Insights From X-Ray Photoelectron Spectroscopy, Ryan Sawyer

Electronic Thesis and Dissertation Repository

In a geological context, glasses are useful analogues for silicate melts as they are more readily studied in the laboratory using a wide range of techniques that are impractical for molten liquids. Understanding the structure of binary silicate glasses can help us understand more about the magmatic processes that affect terrestrial planetary bodies.

Potassium silicate glasses ranging in composition from 10 mol% to 35 mol% K2O were studied using X-ray Photoelectron Spectroscopy (XPS). From high resolution O 1s XPS spectra, Bridging Oxygen (BO) mole fractions were calculated and compared with those of previous 29Si MAS NMR studies. …


Halogen And Non-Traditional Isotope Geochemistry Of Planetary And Terrestrial Materials, Anthony Gargano, Zachary Sharp, Justin Simon, Charles Shearer, Adrian Brearley, James Day 2022 University of New Mexico - Main Campus

Halogen And Non-Traditional Isotope Geochemistry Of Planetary And Terrestrial Materials, Anthony Gargano, Zachary Sharp, Justin Simon, Charles Shearer, Adrian Brearley, James Day

Earth and Planetary Sciences ETDs

This dissertation presents the advances in non-traditional isotope geochemistry of planetary and terrestrial materials encompassing chlorine, sulfur, and zinc isotopes, as well as halogen geochemistry. A wide breadth of materials was studied throughout the completion of this work including iron meteorites, achondrites, chondrites, Apollo lunar samples, as well ancient marine chert, and carbonate sediments. Much of the focus involved the development of a method capable of simultaneously measuring the halogen contents and chlorine isotope compositions of geological materials. Here, I present these data sets to broadly characterize the process of devolatilization of planetary materials, and specifically the problem of ‘halogen-poisoning’ …


White Micas As A Tool For Tracking Pegmatite Evolution And Its Use In Li Exploration. A Case Study Of Wekusko Lake, Manitoba, Canada., David N. Benn 2022 The University of Western Ontario

White Micas As A Tool For Tracking Pegmatite Evolution And Its Use In Li Exploration. A Case Study Of Wekusko Lake, Manitoba, Canada., David N. Benn

Electronic Thesis and Dissertation Repository

The Wekusko Lake pegmatite field is part of the Green Bay Group of pegmatites located near Snow Lake, Manitoba, Canada. Within this field, there are at least 13 spodumene-bearing pegmatites of varying degrees of mineralization. The abundance of white micas and the chemical affinity to incorporate Li and other trace elements into its crystalline structure makes white micas an ideal indicator mineral. The evolution of a melt can be tracked using trace elements in white mica. The K/Rb ratio vs Cs is used to determine a link between increasing evolution and increased Li contents of both the white mica and …


Characterization Of Mumian And Host Rock In Al-Amerat Cave, Oman., Sara Alqamshouai 2022 Western Michigan University

Characterization Of Mumian And Host Rock In Al-Amerat Cave, Oman., Sara Alqamshouai

Honors Theses

Mumian is a sticky black-brown material found in the Mumian cave in Wadi Al Mayh, Al Amerat, Oman. Mumian has been used for centuries as traditional medicine by the local Omani people. Though commonly ingested orally to resolve a variety of common ailments, very little is known about the Mumian material in terms of its chemical composition. The principle aim of this study is to characterize the Mumian and the host rock in terms of the mineralogy and chemical characteristics using a variety of analytic instruments, including XRD, NMR, FT-IR, XRF, and UV- VIS. A secondary goal of this study …


Carbon Capture, Utilization, And Storage, University of North Dakota. Energy and Environmental Research Center 2022 University of North Dakota

Carbon Capture, Utilization, And Storage, University Of North Dakota. Energy And Environmental Research Center

EERC Brochures and Fact Sheets

Fact sheet about carbon capture, utilization, and storage (CCUS) and the Energy & Environmental Research Center’s (EERC’s) CCUS capabilities. Includes information on the Plains CO2 Reduction (PCOR) Partnership initiative, Brine Extraction and Storage Test (BEST), Carbon Storage Assurance Facility Enterprise (CarbonSAFE), Red Trail Energy Carbon Capture and Storage (CCS), a feed study at Coal Creek Station, Bell Creek and Cedar Creek anticline projects, and Partnership for CO2 Capture (PCO2C).


Patterns Of Dissolved Methane In Groundwater And Its Contribution To Emissions Inventories, Amanda E. Campbell 2022 Syracuse University

Patterns Of Dissolved Methane In Groundwater And Its Contribution To Emissions Inventories, Amanda E. Campbell

Dissertations - ALL

The Marcellus Shale is the largest shale gas play in the U.S. production of natural gas using high-volume hydraulic fracturing (HVHF) and production is prevalent throughout the play except in New York (NY), where it is currently banned. High concentrations of methane, the main component of natural gas, in groundwater, as well as its presence in the atmosphere, can have negative consequences. In this dissertation, three aspects of this issue are explored: 1) how and why naturally-occurring methane concentrations vary through time; 2) how elevated naturally-occurring methane concentrations in domestic water wells can be predicted from commonly observed well characteristics; …


Provenance, Composition And Transport Processes Of Pleistocene-Recent Turbidite Sediments Of The Se Nazca Plate, Odp Site 1232, Kimberly D. Beck 2022 Florida International University

Provenance, Composition And Transport Processes Of Pleistocene-Recent Turbidite Sediments Of The Se Nazca Plate, Odp Site 1232, Kimberly D. Beck

FIU Electronic Theses and Dissertations

A 300 meter sequence of Pleistocene turbidite deposits was recovered on the Nazca Plate at the subducting edge of the Peru-Chile Trench at ODP Site 1232. Analysis of the coarsest particles in the turbidite sequences implies sediment was supplied in some proportion by terrestrial erosion and originated in the coastal, central, and Andean volcanic/magmatic belt which parallels the Southern Chilean coast, and the predominant material type is volcanic. Petrographic and geochemical analyses show that samples from 3 - 140 mbsf contain >43% fresh, angular glass. New calcareous nannofossil biostratigraphy brackets the sediment ages of the upper 288 m of cored …


Geochronological And Geochemical Investigation Into Rhyolite Volcanism Of The High Lava Plains And Columbia River Basalt Group Provinces Of Eastern Oregon, Usa, Vanessa Marie Swenton 2022 Portland State University

Geochronological And Geochemical Investigation Into Rhyolite Volcanism Of The High Lava Plains And Columbia River Basalt Group Provinces Of Eastern Oregon, Usa, Vanessa Marie Swenton

Dissertations and Theses

Voluminous and widespread bimodal volcanism has significantly impacted the Pacific Northwest, USA, throughout the Miocene to present day. The two primary volcanic provinces of eastern Oregon include the Columbia River Basalt Group (CRBG) province and the High Lava Plains (HLP) trend. The magmatic and tectonic processes responsible for generating bimodal volcanism, and particularly rhyolites of the ~17-15 Ma CRBG and 12-0 Ma HLP provinces has recently been a popular topic of debate. Rhyolite volcanism of the HLP province has been ascribed to either buoyancy-driven westward plume spreading or to slab rollback and mantle convection spanning from southeast Oregon to Newberry …


Fluid Pathways In Magmatic Fluid-Dominated Hydrothermal System: Upper Resurgent Cone, Brothers Volcano, New Zealand, Esther G. Goita 2022 The University of Southern Mississippi

Fluid Pathways In Magmatic Fluid-Dominated Hydrothermal System: Upper Resurgent Cone, Brothers Volcano, New Zealand, Esther G. Goita

Honors Theses

The Tonga-Kermadec Arc is an active volcanic arc located between New Zealand and Fiji. The arc expands over an approximate distance of 2530 km. The Kermadec Arc is currently host to over 30 volcanoes, the majority of which are submarine. The magmatic activity along the arc is characterized by the convergence between the Pacific and Australian plates. Brothers volcano is the most active hydrothermal system along the Kermadec arc and hosts two distinct hydrothermal systems, one magmatic fluid dominated, and the other seawater dominated, making the site perfect for studying nascent volcanogenic massive sulfide formation and fluid pathways. The International …


Hydrologic Properties Of Mangrove And Sawgrass Peat In Shark River Slough, Everglades, Florida, Nicole Cordoba 2022 Florida International University

Hydrologic Properties Of Mangrove And Sawgrass Peat In Shark River Slough, Everglades, Florida, Nicole Cordoba

FIU Electronic Theses and Dissertations

Peat sediments are the foundation of most wetlands, acting as a medium for water to flow through, governed by hydraulic conductivity, and as a potential source of nutrients. Shark River Slough is a known, main fresh waterway for Everglades National Park, distributing essential nutrients and freshwater into the wetland. Hydraulic conductivity was calculated through experimental (both in situ water and higher salinity water) falling head tests performed on mangrove and sawgrass peat cores. Nutrient concentrations were analyzed for the pore water released during hydrologic testing. Hydraulic conductivity values were higher in the sawgrass peat than the mangrove peat. No significant …


Trace Metal Speciation And Impacts On Iron Oxide Transformations And Biogeochemical Cycling, Jinshu Yan 2022 Washington University in St. Louis

Trace Metal Speciation And Impacts On Iron Oxide Transformations And Biogeochemical Cycling, Jinshu Yan

Arts & Sciences Electronic Theses and Dissertations

Trace metals in anoxic aquatic systems are of great importance for iron oxide transformations and biogeochemical cycling. The presence of trace metal can alter iron oxide transformations under anoxic conditions. Trace metals are also essential for microbially-mediated biogeochemical processes occurring in anoxic wetland soils and stream bed sediments, but low availability of these elements may inhibit anaerobic element cycling and transformations. Trace metal speciation is also vital for understanding the environmental control on nutrients and contaminants. Three projects were conducted to explore trace metal speciation and its associated effect on iron oxide transformations and biogeochemical cycling. First, the Fe(II)-promoted conversion …


Stable Carbon And Oxygen Isotopes Of Early Silurian Pentameride Brachiopods From Québec, Ontario, And Nunavut, And Paleoenvironmental Implications, Jordan N. Siewnarine 2022 The University of Western Ontario

Stable Carbon And Oxygen Isotopes Of Early Silurian Pentameride Brachiopods From Québec, Ontario, And Nunavut, And Paleoenvironmental Implications, Jordan N. Siewnarine

Electronic Thesis and Dissertation Repository

Analysis of low-Mg calcite brachiopod shells for δ18O and δ13C signatures provide quantitative independent geochemical data for paleoenvironmental interpretations. We analyzed 59 brachiopod shells from lower Silurian carbonate rocks of Anticosti Island, the Hudson Bay Lowlands and Niagara regions for spaciotemporal isotopic trends for the early Silurian. Screening tests using scanning electron microscopy, cathodoluminescence and trace element analysis demonstrate exceptional preservation, suggesting retention of primary isotopic values.

δ13C and δ18O values of shells range from 0.2‰ to 2.9‰ and -6.9‰ to -4.3‰ (VPDB), respectively. Temporally, increases in δ13C and δ …


Monitoring Sars-Cov-2 Risk With Co2. The Importance Of Ventilation, Masks, And Vaccinations., Preston Betz 2022 Southern Methodist University

Monitoring Sars-Cov-2 Risk With Co2. The Importance Of Ventilation, Masks, And Vaccinations., Preston Betz

Earth Sciences Theses and Dissertations

To assess airborne pathogen infection risk, concentrations of interior carbon dioxide and changes in relative humidity serve as proxies for human respiration products. Yanes and Yapp, 2010, demonstrated that interior air carbon dioxide concentrations and 13C/12C ratios display a two-component mixing relationship between respiration carbon dioxide which is highly concentrated (>100x atmospheric) in respiration air CO2 at >40,000 ppm compared with ambient air (~410 ppm). In the absence of combustion carbon dioxide, the concentration of carbon dioxide, in an interior space, depends on the rate of respiration CO2 addition relative to the amount of …


Method Development For Preconcentration And Quantification Of Critical And Valuable Elements In Permian Basin Produced Waters, Joshua Matthew Lewis 2022 The University of Texas at El Paso

Method Development For Preconcentration And Quantification Of Critical And Valuable Elements In Permian Basin Produced Waters, Joshua Matthew Lewis

Open Access Theses & Dissertations

Produced waters are a voluminous byproduct of unconventional oil and gas production. Produced water volumes are primarily addressed by subsurface reinjection through saltwater disposal wells (SWDs) and reuse within the oil and gas industry. Oil and gas operators continue to evaluate and trial novel methods to improve produced water handling, and reduce freshwater use, and disposal volumes. Here, we present results for method development to quantify Critical and Valuable Elements (CVEs; defined here as the lanthanide series, high field strength elements, industrial elements and precious metals in brines. CVE concentrations in produced waters and other high-salinity waters are poorly understood …


Core-Cm Williston Basin Carbon Ore, Rare Earth, And Critical Minerals, University of North Dakota. Energy and Environmental Research Center 2022 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.


Alkalinity Enhanced Mass Reduction Of Uranium Contaminated Sediment, Cullen Edward Meurer 2022 University of Wisconsin-Milwaukee

Alkalinity Enhanced Mass Reduction Of Uranium Contaminated Sediment, Cullen Edward Meurer

Theses and Dissertations

Uranium is a toxic and radioactive metal that is naturally occurring in the Earth’s crust. The uranium mining boom of the 1950’s produced many contaminated aquifers throughout the United States. Monitoring of groundwater data suggests that uranium concentrations may take 100’s of years to naturally attenuate to below the maximum contamination limit. This project examines a potential and novel remediation technique of groundwater contaminated with uranium through alkalinity enhanced desorption from the solid phase. Alkalinity enhances the desorption of uranium by complexing uranyl (UO22+) with Ca and CO3 which allows for further desorption. Since remediation is time consuming and expensive, …


Fate And Transport Of Toxoplasma Gondii Oocysts In Saturated Porous Media: Effects Of Electrolytes And Natural Organic Matter, Christian Pullano 2022 Clemson University

Fate And Transport Of Toxoplasma Gondii Oocysts In Saturated Porous Media: Effects Of Electrolytes And Natural Organic Matter, Christian Pullano

All Theses

Toxoplasma gondii is a pathogenic microorganism that is currently a threat to public health. Understanding the fate and transport of T. gondii through the soil and groundwater is vital in determining the risk it poses to water resources and human health. The physico-chemical interactions between the groundwater and the bio colloid within an aquifer will dictate its mobility and its ability to infect humans. This research examines how various naturally occurring groundwater chemistries containing organic compounds and monovalent and divalent salt solutions will alter the fate and transport of T. gondii. Solutions containing various concentrations of humic acid, fulvic …


Wetland Uranium Transport Via Iron-Organic Matter Flocs And Hyporheic Exchange, Connor J. Parker 2022 Clemson University

Wetland Uranium Transport Via Iron-Organic Matter Flocs And Hyporheic Exchange, Connor J. Parker

All Dissertations

Uranium (U) released from the M-Area at the Department of Energy Savannah River Site into Tims Branch, a seasonal wetland and braided stream system, is estimated to be 43,500 kg between 1965 and 1984. The motivation for this work is the uranium’s persistence in the wetland for decades, where it is estimated that 80% of the U currently remains in the Tims Branch wetland. U has begun to incorporate into wetland iron (Fe) and carbon cycles, associating with local Fe mineralogy and deposits of rich wetland organic matter (OM). The objective of this work is to characterize the chemical phases …


Evaluating Alternative Ebullition Models For Predicting Peatland Methane Emission And Its Pathways Via Data–Model Fusion, Shuang Ma, Lifen Jiang, Rachel M. Wilson, Jeff P. Chanton, Scott Bridgham, Shuli Niu, Colleen M. Iversen, Avni Malhotra, Jiang Jiang, Xingjie Lu, Jason Keller, Xiaofeng Xu, Daniel M. Ricciuto, Paul J. Hanson, Yiqi Luo 2022 Northern Arizona University

Evaluating Alternative Ebullition Models For Predicting Peatland Methane Emission And Its Pathways Via Data–Model Fusion, Shuang Ma, Lifen Jiang, Rachel M. Wilson, Jeff P. Chanton, Scott Bridgham, Shuli Niu, Colleen M. Iversen, Avni Malhotra, Jiang Jiang, Xingjie Lu, Jason Keller, Xiaofeng Xu, Daniel M. Ricciuto, Paul J. Hanson, Yiqi Luo

Biology, Chemistry, and Environmental Sciences Faculty Articles and Research

Understanding the dynamics of peatland methane (CH4) emissions and quantifying sources of uncertainty in estimating peatland CH4 emissions are critical for mitigating climate change. The relative contributions of CH4 emission pathways through ebullition, plant-mediated transport, and diffusion, together with their different transport rates and vulnerability to oxidation, determine the quantity of CH4 to be oxidized before leaving the soil. Notwithstanding their importance, the relative contributions of the emission pathways are highly uncertain. In particular, the ebullition process is more uncertain and can lead to large uncertainties in modeled CH4 emissions. To improve model simulations …


Evaluating Alternative Ebullition Models For Predicting Peatland Methane Emission And Its Pathways Via Data–Model Fusion, Shuang Ma, Lifen Jiang, Rachel M. Wilson, Jeff P. Chanton, Scott Bridgham, Shuli Niu, Colleen M. Iversen, Avni Malhotra, Jiang Jiang, Xingjie Lu, Yuanyuan Huang, Jason Keller, Xiaofeng Xu, Daniel M. Ricciuto, Paul J. Hanson, Yiqi Luo 2022 Northern Arizona University

Evaluating Alternative Ebullition Models For Predicting Peatland Methane Emission And Its Pathways Via Data–Model Fusion, Shuang Ma, Lifen Jiang, Rachel M. Wilson, Jeff P. Chanton, Scott Bridgham, Shuli Niu, Colleen M. Iversen, Avni Malhotra, Jiang Jiang, Xingjie Lu, Yuanyuan Huang, Jason Keller, Xiaofeng Xu, Daniel M. Ricciuto, Paul J. Hanson, Yiqi Luo

Biology, Chemistry, and Environmental Sciences Faculty Articles and Research

Understanding the dynamics of peatland methane (CH4) emissions and quantifying sources of uncertainty in estimating peatland CH4 emissions are critical for mitigating climate change. The relative contributions of CH4 emission pathways through ebullition, plant-mediated transport, and diffusion, together with their different transport rates and vulnerability to oxidation, determine the quantity of CH4 to be oxidized before leaving the soil. Notwithstanding their importance, the relative contributions of the emission pathways are highly uncertain. In particular, the ebullition process is more uncertain and can lead to large uncertainties in modeled CH4 emissions. To improve model simulations of CH4 emission and its pathways, …


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