Open Access. Powered by Scholars. Published by Universities.®

Earth Sciences Commons™

Open Access. Powered by Scholars. Published by Universities.®

Geochemistry

Institution
Keyword
Publication Year
Publication
Publication Type
File Type

Articles 121 - 150 of 1546

Full-Text Articles in Earth Sciences

Chemical And Morphological Characterization Of Airborne Particulate Matter At The Jackpile-Paguate Mine, Pueblo Of Laguna, New Mexico: Implications For Potential Metals Exposure, Andreanna C. Roros Jul 2024

Chemical And Morphological Characterization Of Airborne Particulate Matter At The Jackpile-Paguate Mine, Pueblo Of Laguna, New Mexico: Implications For Potential Metals Exposure, Andreanna C. Roros

Earth and Planetary Sciences ETDs

The inhalation of windblown particulate matter (PM) derived from abandoned uranium mines (AUMs) is a potential environmental health risk to Native American communities that live in proximity to these sites. However, the aeolian transport of metal-bearing PM from AUMs, as a potential exposure pathway, has not been investigated in any detail. In this study, we sampled airborne particulate matter within the Jackpile Mine located on the lands of the Pueblo of Laguna, New Mexico using passive sampling methods to understand the characteristics of dust within the mine site. The objective was to determine the elemental concentrations, mineralogy, and morphology of …


Carbonate And Organic Proxies And The Impacts Of Climate On Lake Systems: Paleoclimate Interpretations From Lake Chalco, Mexico, Aria Holmes Jul 2024

Carbonate And Organic Proxies And The Impacts Of Climate On Lake Systems: Paleoclimate Interpretations From Lake Chalco, Mexico, Aria Holmes

Earth and Planetary Sciences ETDs

This project incorporates several lines of evidence to better understand the climate at Lake Chalco. Chapter 1 utilizes oxygen isotopes from carbonates and show that the Inter Tropical Convergence Zone varies on primarily glacial and millennial timescales; precession is not observed. These data indicate glacials periods were shallower and interglacials were wetter periods at Lake Chalco. Chapter 2 studies carbon, nitrogen, C/N, and TOC proxies and finds that the lake conditions during the glacials and interglacials are primarily a mixed algal-macrophyte-terrestrial organic matter. Deviations show that the lake during the interglacials had more algal organic matter- reflecting influxes of nutrients …


Resolving Antarctic Margin Paleoceanography For Two Different Timescales And Archives, Theresa M. King Jun 2024

Resolving Antarctic Margin Paleoceanography For Two Different Timescales And Archives, Theresa M. King

USF Tampa Graduate Theses and Dissertations

Recent decades have seen increased rates of ice mass loss from Antarctic ice sheets, through thinning of many ice shelves around the periphery of the continent. The most vulnerable are the glacial systems that are marine-terminating and grounded below sea level, a characteristic that exposes these systems to sea level rise and warming oceans. Enhanced basal melting under the influence of warm ocean water masses can lead to thinning and retreat of glaciers, and ultimately to the acceleration of grounded ice loss. To contextualize current ice mass loss and contribute to accurate model projections for future retreat scenarios, it is …


Antarctic Atmosphere-Ocean-Ice Interactions During Past Warm Climates: An Ice-Proximal Perspective, Imogen Mireille Browne Jun 2024

Antarctic Atmosphere-Ocean-Ice Interactions During Past Warm Climates: An Ice-Proximal Perspective, Imogen Mireille Browne

USF Tampa Graduate Theses and Dissertations

Antarctica’s ice sheets contain 58 m of sea level equivalent ice and thus exert a fundamental control on global sea level on decadal to million-year timescales. Interactions between Antarctica’s ice sheets, regional atmospheric circulation, and the Southern Ocean influence ice sheet mass balance, sea ice formation, and deep water production, which regulate Earth’s climate. At present, Antarctica’s fringing ice shelves and outlet glaciers, particularly in West Antarctica, are losing mass as warm ocean waters move landward across the continental shelves, melting the underside of ice shelves and eroding glacial grounding lines. In East Antarctica, net ice mass gain is occurring …


Role Of Hypogenesis In The Evolution Of Karst In The Taurus Mountains Range, Turkey, Serdar C. Bayari, Naciye Nur Özyurt, Lütfi Nazik, Koray A. Törk, Noyan İ. Güner, Emrah Pekkan, Pınar Avcı Jun 2024

Role Of Hypogenesis In The Evolution Of Karst In The Taurus Mountains Range, Turkey, Serdar C. Bayari, Naciye Nur Özyurt, Lütfi Nazik, Koray A. Törk, Noyan İ. Güner, Emrah Pekkan, Pınar Avcı

International Journal of Speleology

Field observations and laboratory data collected from the Taurus Mountains Range, Turkey during the last two decades provided evidence for the link between the evolution of hypogene karst and the geodynamic history. Major evidence includes; carbonate-hosted secondary ore deposits that are converted from primarily hypogene minerals by epigene, oxygen-rich groundwater circulating at local to intermediate depths. Another piece of evidence of hypogene karst in the Tauride is the Kırkgöz springs’ huge submerged cave/conduit system, which formed the Antalya Travertine Plateau, which is the world’s largest deposit precipitated by cool karst groundwater. The obruks in central Tauride are giant collapse dolines …


Searching For The Hyperobject: Crystals As Transscalar Vehicles, Jay Costello Jun 2024

Searching For The Hyperobject: Crystals As Transscalar Vehicles, Jay Costello

Masters Theses

When I touch the street outside my house, I'm touching Los Angeles—a contiguous vector of material bisecting a continent. A slab, a stone, dust and oil, a googolplex of tightly packed anisotropic particles... At nightfall, I sneak to the edge of the highway and break off a piece. 'What does it mean for a worm to be aware of the scale of the planet?' Bruno Latour's evocative questioning of scalar jumps prompts an existentialism that places me somewhere between the hyperlocal and the massively distributed. Like a cosmic traveler floating through the universe, I feel adrift. I look around, grasping …


Lead Along Arid Route 66: Concentration, Fate, Surface Transport, And Awareness, Dominic Joel Ombati Jun 2024

Lead Along Arid Route 66: Concentration, Fate, Surface Transport, And Awareness, Dominic Joel Ombati

Loma Linda University Electronic Theses, Dissertations & Projects

Fate and transport of lead (Pb) are well studied in humid, high precipitation environments. Few studies have compared or addressed fate of lead (Pb) in arid, low precipitation areas where the soil binding capacity may differ from classic studies. The goal of this study is to identify the control of fate and transport in the arid section of Route 66 by determining the concentration, chemical forms, and surface transport mechanism of lead (Pb) along the arid section of Route 66. Understanding the fate and transport of lead (Pb) in different environments is key in the environmental mitigation of lead (Pb) …


Using A Novel Chain Of Chemical, Crystallographic, And Isotopic Analytical Techniques To Examine The Formation Histories Of Features In Chondritic Meteorites And Orbicular Granites, Samuel P. Alpert Jun 2024

Using A Novel Chain Of Chemical, Crystallographic, And Isotopic Analytical Techniques To Examine The Formation Histories Of Features In Chondritic Meteorites And Orbicular Granites, Samuel P. Alpert

Dissertations, Theses, and Capstone Projects

Understanding the chemistry, crystallography, and isotopic variability of minerals allows us to place significant constraints on the formation history of their host rocks. These constraints provide insight into everything from the distribution of water in the solar system to the onset of plate tectonics. Electron beam instruments and ion probes are important tools used by modern geologists to obtain crystallographic, chemical, and isotopic data. Here I present a new workflow, using these instruments, combining wavelength dispersive spectrometry (WDS), backscattered electron (BSE) imaging, machine learning algorithms, electron backscatter diffraction (EBSD), and secondary ion mass spectroscopy (SIMS), to place quantitative constraints on …


Geochemistry And Geochronology Of The Steens And Monument Dike Swarm: Implications And Relationships To Magmatic Storage And To Lava Flows Of The Picture Gorge And Steens Basalt, Rachel Anne Sweeten May 2024

Geochemistry And Geochronology Of The Steens And Monument Dike Swarm: Implications And Relationships To Magmatic Storage And To Lava Flows Of The Picture Gorge And Steens Basalt, Rachel Anne Sweeten

Dissertations and Theses

The Columbia River Basalt Group (CRBG) is the youngest and best-preserved example of a continental flood basalt province. Vents and dikes for the four main eruptive units (Steens, Imnaha, Grande Ronde, and Picture Gorge Basalt) are the Monument, Steens and Chief Joseph Dike Swarms located in eastern Oregon, southeastern Washington, and northern Nevada.

Here we report on the compositions and timing of the dikes and sills of the Monument Dike Swarm (MDS), as well as their relationship to the subaerial lava flows of the Picture Gorge Basalt (PGB) with implications for crustal storage of these magmas. We evaluate data from …


Investigating The Formation Of The Zirconium-Rich Lithologies Of The Grenville Province Using Zircon Thermometry Of Granitoids From The Adirondack Mountains, John St. Denny May 2024

Investigating The Formation Of The Zirconium-Rich Lithologies Of The Grenville Province Using Zircon Thermometry Of Granitoids From The Adirondack Mountains, John St. Denny

Theses - ALL

The Grenville Province (1200-980 Ma) is known to consist of many rocks which are abundant in zircon. This is seen by the large size of Grenville-age zircons and their abundance in the detrital record. A possible explanation for this is the temperature at which these rocks formed. This hypothesis states that the melts which formed the zircon-rich Grenville lithologies were exceptionally high temperature, enabling them to incorporate a significant amount of zirconium. As it is believed that most zirconium in a melt is incorporated into zircon, a high concentration of zirconium in a magma would crystallize an abundance of zircon. …


The Geology And Geochemistry Of The Western Iron Ore Group Greenstone Belt, Singhbhum Craton, Eastern India, Jordan Wright May 2024

The Geology And Geochemistry Of The Western Iron Ore Group Greenstone Belt, Singhbhum Craton, Eastern India, Jordan Wright

Earth Sciences Theses and Dissertations

This thesis presents new data on the origin of the Western Iron Ore Group (W-IOG), a Paleoarchean succession deposited on sialic rocks of the Singhbhum Craton. U-Pb ages from zircons from a tuff overlying the Lower Shales just below a banded iron formation (BIF) pin the age of the section to 3.39 Ga. Unconformably overlying the whole IOG section is the Darjing Group, which contains the Birtola Sandstone (on the basis of this work, now estimated to be 2.35 Ga). The lack of penetrative deformation and low-grade metamorphism makes these rocks excellent subjects for combined radiogenic and stable isotope studies. …


Investigation Of Residual Mineral Content Of Bauxite Stockpiles, Saline Mining District, Arkansas, U.S.A., Melanie L. Ertons May 2024

Investigation Of Residual Mineral Content Of Bauxite Stockpiles, Saline Mining District, Arkansas, U.S.A., Melanie L. Ertons

Electronic Theses and Dissertations

The former mining town of Bauxite is in the Saline County Mining District, in central Arkansas. Bauxite is located approximately 40 km (25 mi) southwest of Little Rock just east of Benton, Arkansas. This area contains extensive deposits of bauxite ore and nepheline syenite previously mined by Aluminum Company of America using open pit and subsurface mining techniques. This study incorporates five bauxite stockpiles (SP1, Clay, SP2, SP3, SP4) with varying amounts of alumina content situated on approximately 10 acres of land within an area of the former mine recognized as Section 20. Over the past several years, there has …


Depositional Facies Analysis Of The Cotton Valley Group Sandstones Of The Blackburn Field, Northern Louisiana Using Well Logs And Cores; Implications For Carbon Sequestration, Frederick Owusu May 2024

Depositional Facies Analysis Of The Cotton Valley Group Sandstones Of The Blackburn Field, Northern Louisiana Using Well Logs And Cores; Implications For Carbon Sequestration, Frederick Owusu

Electronic Theses and Dissertations

The Cotton Valley Group (CVG) consists of tight sandstones with heterogeneous reservoir properties due to variations in depositional environments and diagenesis, spanning across eastern Texas through the Florida panhandle. It has served as a hydrocarbon target since the 1940s, and with recent technological advances, there is renewed exploration of the tight reservoirs within the group. Across northern Louisiana, the CVG has moderate to good reservoir properties, whereas those south extending westward across the Sabine uplift into east Texas decrease in porosity and permeability. With reservoir depletion coupled with its relatively simple mineralogy, these sandstone units may serve as good, localized …


Introduction To Nuclear Magnetic Resonance Spectroscopy In A Geochemical Setting, Evan Mack May 2024

Introduction To Nuclear Magnetic Resonance Spectroscopy In A Geochemical Setting, Evan Mack

University Honors College

Nuclear magnetic resonance (NMR) spectroscopy is a powerful analytical tool that is heavily employed in organic chemistry, but lacks use in geochemistry. The technique is most useful for characterization and structural analysis of analytes, but also sees use in kinetics analysis, speciation, and detection. This work aims to answer these questions regarding NMR spectroscopy’s use in geochemical settings: Which nuclei are studied? For what purposes is each nucleus studied? What affects the scope of the technique and has caused it to not be widely used? How often is NMR spectroscopy used? What trends are there in the technique’s use? The …


The Effects Of Amphibole- And Sulfide-Producing Melts On Crustal Strength In Gabbros Of Lower Oceanic Crust In Oceanic Core Complexes, Mid-Atlantic And Southwest Indian Ridges, Trevor Hoffmann May 2024

The Effects Of Amphibole- And Sulfide-Producing Melts On Crustal Strength In Gabbros Of Lower Oceanic Crust In Oceanic Core Complexes, Mid-Atlantic And Southwest Indian Ridges, Trevor Hoffmann

Master's Theses

This study investigates gabbro-cored oceanic core complexes in the slow-spreading Mid-Atlantic Ridge (MAR) and the ultraslow spreading Southwest Indian Ridge (SWIR). Dikelets are a texture found in thin section samples from these systems that form as a result of crystal-plastic deformation. Thin section samples from the Atlantis Massif, MARK Area, and 13˚-15˚ North of the MAR and the Atlantis Bank of the SWIR were observed with petrography to find these dikelets and identify what type of dikelet is present. SEM-EDS is used to identify the mineral assemblages present in the dikelets. LA-ICP-MS is used on amphibole to determine if its …


Investigating Changes In Surface Water Chemistry Across The Llano Uplift And The Balcones Fault Zone In Central Texas Using Strontium And Uranium Isotopes, Hao Tuan Pham May 2024

Investigating Changes In Surface Water Chemistry Across The Llano Uplift And The Balcones Fault Zone In Central Texas Using Strontium And Uranium Isotopes, Hao Tuan Pham

Open Access Theses & Dissertations

The landscape of central Texas is shaped by over one billion years of Earth's history. An array of lithology lies within central Texas along with two large geological structures. The Llano Uplift, characterized by Proterozoic metamorphic and igneous rocks dating back to 1.37 billion years ago, is encircled by Paleozoic and Mesozoic sedimentary rocks. To the southeast of the Llano Uplift lies the Balcones Fault Zone (BFZ), an extensional structural system of mostly normal faults that delineates the transition between Paleozoic-Mesozoic sedimentary rocks and Cenozoic sedimentary cover, which are influential to the regional hydrogeology. This study investigates the hydrogeological dynamics …


Investigating Controls On Temporal And Spatial Variation Of Dissolved Uranium At Springs In Horn Creek Drainage, Grand Canyon National Park, Arizona, Usa, Collin Davidson May 2024

Investigating Controls On Temporal And Spatial Variation Of Dissolved Uranium At Springs In Horn Creek Drainage, Grand Canyon National Park, Arizona, Usa, Collin Davidson

UNLV Theses, Dissertations, Professional Papers, and Capstones

Groundwater is a critical resource in the Grand Canyon, providing water to local communities, millions of annual visitors, and ecosystems. One major concern for this critical resource is the potential for uranium contamination in conjunction with uranium mining efforts. Upper Horn Bedrock Spring (UHB) in the Horn Creek drainage of the Grand Canyon sits below the oldest uranium mine in the region, Orphan Lode mine. UHB spring contains the highest concentration of dissolved uranium in the region, eclipsing the Maximum Contaminant Level (MCL) set by the USEPA by an order of magnitude on average. This research and recent collaboration with …


Evaluation Of Heavy Metal Pollution, Water Quality, And The Effectiveness Of Remedial Sediment Dredging In The Lower Passaic River, New Jersey, Oluwafemi Soetan May 2024

Evaluation Of Heavy Metal Pollution, Water Quality, And The Effectiveness Of Remedial Sediment Dredging In The Lower Passaic River, New Jersey, Oluwafemi Soetan

Theses, Dissertations and Culminating Projects

Toxic metal pollution is a leading environmental concern for aquatic systems globally and remedial dredging has been widely employed to mitigate its harmful impacts. In terms of the short-term impacts of remedial dredging, mixed results are reported in several studies. Despite its immediate negative impacts including saturation of water with toxic metals, increased turbidity, and sediment resuspension, positive impacts can be recorded over a stabilization period of 6 – 24 months after dredging. Nevertheless, the sustainability of these recorded positive effects cannot be ascertained as some studies have reported long-term regression in remediated sites’ conditions. Evaluation of success determinants, site-measure …


Geochemical Analysis Of Basement Rock As A Potential Metal Source In Mississippi Valley-Type Ores, Southern Midcontinent U.S.A., Mackenzie Moorhead May 2024

Geochemical Analysis Of Basement Rock As A Potential Metal Source In Mississippi Valley-Type Ores, Southern Midcontinent U.S.A., Mackenzie Moorhead

Graduate Theses and Dissertations

Mississippi Valley-Type (MVT) ores are epigenetic, sedimentary hydrothermal base metal deposits that exist worldwide with type localities in the midcontinent United States. These Permian-aged sulfide ores represent an extraordinary concentration of economic metals, Pb and Zn. Ore deposits occur in vast districts that have a rich mining history. The Pb and Zn from these deposits account for 24% of worldwide reserves. The geologic processes responsible for MVT ore genesis are not fully understood, especially the sourcing of ore constituents. In the midcontinent, the Ouachita Orogeny expelled saline hydrothermal brines in response to high rates of subsidence. These fluids migrated through …


Determining The Climatic Effects Of The Central Atlantic Magmatic Province Across The End Triassic Mass Extinction In The Elliot Formation, Southern Africa, Danielle Elizabeth Oberg May 2024

Determining The Climatic Effects Of The Central Atlantic Magmatic Province Across The End Triassic Mass Extinction In The Elliot Formation, Southern Africa, Danielle Elizabeth Oberg

Graduate Theses and Dissertations

Understanding the intricate relation between carbon-cycle perturbations, climate change, and biodiversity stability is crucial in the face of ongoing anthropogenic greenhouse-gas emissions. This thesis explores the impacts of rapid climate change induced by carbon-cycle perturbations and their potential repercussions on global climate. Large igneous provinces, particularly the Central Atlantic Magmatic Province, offer a lens through which to examine the nexus of volcanic activity, mass extinctions, and climate change. The emplacement of Central Atlantic Magmatic Province, covering vast regions across continents, emitted substantial amounts of carbon dioxide, profoundly impacting global climate and ecosystems. The end-Triassic Mass Extinction, attributed to Central Atlantic …


Terrestrial Exchange Of Atmospheric Metals: Insights From Fallout Radionuclides, Joshua D. Landis Apr 2024

Terrestrial Exchange Of Atmospheric Metals: Insights From Fallout Radionuclides, Joshua D. Landis

Dartmouth College Ph.D Dissertations

Forests mediate the exchange of gases and particulate matter (PM2.5 and PM10) between terrestrial ecosystems and the atmosphere over 30% of global land area. Because forest foliage efficiently absorbs PM with persistent pollutants including metals Pb and Hg, as well as CO2 and gaseous elemental mercury (GEM), this exchange profoundly influences the composition of the atmosphere as well as terrestrial biogeochemical cycles. The processes by which PM is absorbed remain enigmatic, however, due to the complexity of micrometeorological physics and submicron physical scale of the interaction. Here, measurements of fallout radionuclides (FRNs) beryllium-7 and lead-210, which are quintessential tracers …


Evaluating Reclaimed Mines And Heavy Metal Soil Contamination, Torin A. Matthews Apr 2024

Evaluating Reclaimed Mines And Heavy Metal Soil Contamination, Torin A. Matthews

ATU Scholars Symposium

Arkansas has a rich history of lead and zinc mining. While there are still some active mines, many historical mines have been abandoned and/or reclaimed. Although most reclamation procedures result in the burial and containment of target minerals, accessory minerals and elements can be leached out of waste materials/tailings piles and include heavy metals (i.e., Pb, As, Cd). We aim to evaluate the soil and watershed of a few abandoned/reclaimed mines in Pope County, AR, for the presence of heavy metals/source minerals. Soil and stream sediment geochemistry will be conducted using a portable x-ray fluorescence analyzer. Field work and sampling …


Investigation Of Temporal Variation In Sediment Deposition Within The Tropical Wouri Estuary Cameroon Using Fourier Transform Infrared Spectroscopy, Olumide Ajulo, Dr. Henry Agbogun, Dr. Hendratta Ali Apr 2024

Investigation Of Temporal Variation In Sediment Deposition Within The Tropical Wouri Estuary Cameroon Using Fourier Transform Infrared Spectroscopy, Olumide Ajulo, Dr. Henry Agbogun, Dr. Hendratta Ali

SACAD: Scholarly Activities

In this study, Fourier Transform Infrared Spectroscopy (FTIR) was employed to qualitatively analyze organic and mineral components of the sediment core collected from the Wouri Estuary. The FTIR spectra revealed distinct transmittance corresponding to different organic and mineral phases, allowing for the characterization of sediment composition. The FTIR spectra showed changes and variation progressively from the bottom to the top. These sediments are proxies for time this can be inferred to say deposition in the Wouri Estuary has always changed.


Qualitative Analysis Of Selected Hydrocarbon Produced In Kansas Using Ftir: An Oil-Oil Correlation Study, Oluwaseun Omoyemi, Henry Agbogun, James Titah Apr 2024

Qualitative Analysis Of Selected Hydrocarbon Produced In Kansas Using Ftir: An Oil-Oil Correlation Study, Oluwaseun Omoyemi, Henry Agbogun, James Titah

SACAD: Scholarly Activities

Hydrocarbons have been produced in Kansas since the 1860s, however, the properties and characteristics of the produced oil are still poorly understood.

An oil-oil correlation analysis has been conducted on twelve hydrocarbon samples from three subbasins and from five producing intervals within the State of Kansas. Fourier Transform Infrared Radiation (FTIR) was used to characterize the organic functional groups present within the samples and Thin Layer Chromatography (TLC) was used to assess the hydrocarbon fractions in the samples. The FTIR spectrum of all the samples exhibit similar peaks implying similar functionally groups were present in all the samples. The TLC …


Applied Depositional Geosystems Of The Coos Bay Basin, Oregon: Organic Geochemistry, Maturation, Paleoenvironmental Reconstruction And Biostratigraphy Of The Coaledo Delta During The Middle Eocene Climatic Optimum (Meco), Allison K. Barbato Apr 2024

Applied Depositional Geosystems Of The Coos Bay Basin, Oregon: Organic Geochemistry, Maturation, Paleoenvironmental Reconstruction And Biostratigraphy Of The Coaledo Delta During The Middle Eocene Climatic Optimum (Meco), Allison K. Barbato

LSU Doctoral Dissertations

The Coos Bay Basin on the southwestern coast of Oregon is a forearc basin that contains exceptionally preserved Eocene to Miocene, tidal to wave-dominated, shallow deltaic to deep marine sediments of the Coaledo Delta. Coastal depositional environments are known to host source, reservoir, and seal rocks. Climate, topographic relief, and geographical position all play an important role in regional vegetation development and oceanic setting. This study assesses 84 outcrop and 12 core samples from Coos Bay for their organic geochemical characteristics and microfossil assemblage to provide source rock characterization information, organofacies descriptions, environmental reconstructions, and age control.

Results indicate the …


Unearthing The Past: A Comprehensive Study Of Natural And Anthropogenic Changes At An Archaeological Site Through Hydrogeologic Connectivity Utilizing Gis, Mehlich Ii Phosphorus Extractant, And Ph, Dana L. F. Herren Apr 2024

Unearthing The Past: A Comprehensive Study Of Natural And Anthropogenic Changes At An Archaeological Site Through Hydrogeologic Connectivity Utilizing Gis, Mehlich Ii Phosphorus Extractant, And Ph, Dana L. F. Herren

Theses

This thesis aims to thoroughly analyze the Mehlich II Phosphorus Extractant and pH levels at the Bains Gap Village Site in Anniston, AL., while examining the impact of various environmental factors and human activities on them. Phosphorus is often used in archaeology as an indicator of human activity. Soil core samples were collected to analyze anomalies in phosphorus levels.

To establish any relationships, phosphorus and pH levels from soil cores were correlated with findings from past excavation units and features. The potential effects of hydrogeologic connectivity on soil phosphorus and pH levels were investigated. Geospatial technologies were used to manage …


Transport Of Multi-Phase Multi-Component Fluids In The Shallow Subsurface Influenced By Soil And Surface Boundary Conditions: Experimental And Numerical Study With Application To Natural Gas Leakage, Navodi Jayarathne Apr 2024

Transport Of Multi-Phase Multi-Component Fluids In The Shallow Subsurface Influenced By Soil And Surface Boundary Conditions: Experimental And Numerical Study With Application To Natural Gas Leakage, Navodi Jayarathne

Civil and Environmental Engineering Theses and Dissertations

With the increased use of Natural Gas (NG) as a source of fuel, underground leak-related events are increasingly reported, and some are fatal. Subsurface migration and development up to flammable limits are highly dependent on leak characteristics, soil, atmospheric variables, and other surface and subsurface structural complexities. Although few studies have characterized the transient behavior of leaked NG in the shallow subsurface, the underlying mechanisms and their interactions are not well understood, which prevents prediction of the impact of environmental and operating conditions on gas migration. The study conducted a series of field scale-controlled release experiments and numerical simulations to …


Remote Sensing Techniques To Determine Volcanic Gas Components And Fluxes: Application For Lascar, Chile And Fagradalsfjall, Iceland Volcanos., Felipe S. Rojas Vilches Apr 2024

Remote Sensing Techniques To Determine Volcanic Gas Components And Fluxes: Application For Lascar, Chile And Fagradalsfjall, Iceland Volcanos., Felipe S. Rojas Vilches

Earth and Planetary Sciences ETDs

Volcanic plumes allow us to understand different aspects of a volcanic system including magma movements, dynamics, mass transfer, overall gas emissions to the atmosphere, and many processes that impact human life. However, the H₂O gas is poorly constrained due to the intrinsic difficulties of this gas, with high background values and easily dispersed/integrated into the background. In this work we study the gas emissions from Lascar volcano, and Fagradalsfjall volcano, in Chile and Iceland, respectively, using a combination of different ground-based remote sensing techniques and in situ plume measurements, we measure H₂O, SO₂, CO₂, CO, and H₂S from longer and …


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 …


Correlation Of Geochemical Zones In Great Onyx Cave, Mammoth Cave National Park, To Surficial Geological Units, William Strehl Jan 2024

Correlation Of Geochemical Zones In Great Onyx Cave, Mammoth Cave National Park, To Surficial Geological Units, William Strehl

Mahurin Honors College Capstone Experience/Thesis Projects

Cave passages in Great Onyx Cave, developed within the Girkin and Ste. Genevieve Limestones of Mammoth Cave National Park, contain a variety of secondary features on cave walls, including speleothems such as stalactites, stalagmites, and flowstone, evaporite minerals, and dissolution features such as pits and domes. What secondary features are present on the walls of a cave passage depends on the flow and geochemistry of capillary water that has interacted with the cave passage. In the Mammoth Cave aquifer, five distinct geochemical zones have been broadly defined and each typically contains a particular set of secondary features. Geochemical zonation in …