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Temporal Lidar Scanning In Quantifying Cumulative Rockfall Volume And Hazard Assessment: A Case Study At Southwestern Saudi Arabia, Abdullah A. Alotaibi, Norbert H. Maerz, Kenneth J. Boyko, Ahmed M. Youssef, Biswajeet Pradhan 2022 Missouri University of Science and Technology

Temporal Lidar Scanning In Quantifying Cumulative Rockfall Volume And Hazard Assessment: A Case Study At Southwestern Saudi Arabia, Abdullah A. Alotaibi, Norbert H. Maerz, Kenneth J. Boyko, Ahmed M. Youssef, Biswajeet Pradhan

Geosciences and Geological and Petroleum Engineering Faculty Research & Creative Works

Rockfalls and unstable slopes pose a serious threat to people and property along roads/highways in the southwestern mountainous regions of Saudi Arabia. In this study, the application of terrestrial light detection and ranging (LiDAR) technology was applied aiming to propose a strategy to analyze and accurately depict the detection of rockfall changes, calculation of rockfall volume, and evaluate rockfall hazards along the Habs Road, Jazan Region, Saudi Arabia. A series of temporal LiDAR scans were acquired at three selected sites. Our results show that these three sites have different degrees of hazard due to their geological differences. The mean ...


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 ...


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 ...


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 acid ...


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 ...


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 of ...


Connections Between Interglacial Variation And Lithological Variability Within Midland Basin Permian Shale Rocks In Martin County, Texas, Helen Rice Hammon 2022 Louisiana State University at Baton Rouge

Connections Between Interglacial Variation And Lithological Variability Within Midland Basin Permian Shale Rocks In Martin County, Texas, Helen Rice Hammon

LSU Master's Theses

The Upper Pennsylvanian (323.2–289.9 Ma) and Lower Permian (289.9-251 Ma), (Wolfcamp and Spraberry formations) interval of the Midland Basin, West Texas, contains a mixed succession of shale, carbonate, and siltstone/sandstone lithofacies that accumulated in a deep-water marine environment under variable hydrographic restrictions. The heterogenous stratigraphy found in the Wolfcamp and Spraberry formation was formed in response to variations in sea level and a transition from a glacial to an interglacial climate during the Early Permian. These fluctuations left behind alternating beds of mudstone and carbonate, interwoven with thin sandstone beds. Because the Wolfcamp and Spraberry ...


Investigation Of Sulphide-Poor Gold Mineralization At The Deep A Zone, Kiena Complex, Québec, Stephanie A. Kobylinski 2022 The University of Western Ontario

Investigation Of Sulphide-Poor Gold Mineralization At The Deep A Zone, Kiena Complex, Québec, Stephanie A. Kobylinski

Electronic Thesis and Dissertation Repository

The Kiena Complex is located halfway between Malartic and Val d’Or in Québec, within the Abitibi Greenstone belt in the Superior Province. This study examined mineralization at the Kiena Complex using detailed core logging, geochemical analysis of wall rock, petrography, EPMA, and gold deportment studies. The analysis and interpretations indicate that the unique sulphide-poor gold-rich quartz veins of the Deep A Zone at the Kiena Complex contain 500 μm2) are located at the contact of quartz and corroded albite grains, and fine gold grains (5-500 μm2) are hosted within the corroded albite.


Connections Between Interglacial Variation And Lithological Variability Within Midland Basin Permian Shale Rocks In Martin County, Texas, Helen Rice Hammon 2022 Louisiana State University at Baton Rouge

Connections Between Interglacial Variation And Lithological Variability Within Midland Basin Permian Shale Rocks In Martin County, Texas, Helen Rice Hammon

LSU Master's Theses

The Upper Pennsylvanian (323.2–289.9 Ma) and Lower Permian (289.9-251 Ma), (Wolfcamp and Spraberry formations) interval of the Midland Basin, West Texas, contains a mixed succession of shale, carbonate, and siltstone/sandstone lithofacies that accumulated in a deep-water marine environment under variable hydrographic restrictions. The heterogenous stratigraphy found in the Wolfcamp and Spraberry formation was formed in response to variations in sea level and a transition from a glacial to an interglacial climate during the Early Permian. These fluctuations left behind alternating beds of mudstone and carbonate, interwoven with thin sandstone beds. Because the Wolfcamp and Spraberry ...


The Mineralogy And Geochemistry Of Illinois Basin Paleosols: Recognizing Detrital, Pedogenic, And Diagenetic Minerals, Julia A. McIntosh 2022 Southern Methodist University

The Mineralogy And Geochemistry Of Illinois Basin Paleosols: Recognizing Detrital, Pedogenic, And Diagenetic Minerals, Julia A. Mcintosh

Earth Sciences Theses and Dissertations

The geochemical compositions of minerals in paleosols are assumed to be homogenous and attained through chemical weathering processes during episodes of pedogenesis in the geologic past. As such, the geochemical composition of minerals from paleosols may be used to reconstruct ancient climates and environments. One problem with this assumption is that paleosols were initially clastic sedimentary rocks or substrate prior to pedogenesis, thus it is likely that some portion of the paleosol is still composed of detrital minerals. Secondly, conditions may change in a sedimentary basin as the basin is buried and later uplifted, potentially triggering new mineralization or transformation ...


Honey As A Biomonitor For Air Pollutant Deposition In The Eastern United States Using Ion Chromatography And Scanning Electron Microscopy, Cole Cochran 2022 William & Mary

Honey As A Biomonitor For Air Pollutant Deposition In The Eastern United States Using Ion Chromatography And Scanning Electron Microscopy, Cole Cochran

Undergraduate Honors Theses

Anthropogenic activities generate metal, acid, and particulate air pollutants which negatively impact human and ecological health. In the United States, power plant, industrial, and vehicle emissions are leading causes of air pollution, however, the measurement of air pollution at high-resolution spatial regimes remains a challenge. Honey has emerged as a powerful biomonitoring tool to effectively quantify contaminants without the need for a large array of monitoring instruments. I hypothesized that honey could be used to effectively measure and map modern air pollutant spatiotemporal relationships over the Eastern U.S. Using ion chromatography with sulfate as an indicator for air pollution ...


Geologic Controls On 137cs Cycling By Terrestrial Vegetation In The Eastern U.S., Kathleen Chellman 2022 William & Mary

Geologic Controls On 137cs Cycling By Terrestrial Vegetation In The Eastern U.S., Kathleen Chellman

Undergraduate Honors Theses

137Cs is a radioactive trace metal (T1/2 = 30 y) that was dispersed globally by nuclear weapons testing in the 1950s-1960s. Prevailing winds and precipitation systems caused some areas far from the test sites to receive significant fallout, which is still easily measured in soils, sediments and even some vegetation in the Eastern United States. Recent work near Chernobyl and Fukushima indicates that trace levels of 137Cs can harm insects, pollination services, and other ecological functions. In areas with low soil potassium, 137Cs is cycled in vegetation; however, soil potassium alone doesn't consistently predict the ...


Improving The Hydrological Analysis Of Groundwater Flow Paths By Integrating Geochemical And Physical Characteristics Of A Highly Fractured Aquifer System To Create Sustainable Use Of Groundwater In A Climate With Projected Drying Trends., Marsha K. Allen 2022 University of Massachusetts Amherst

Improving The Hydrological Analysis Of Groundwater Flow Paths By Integrating Geochemical And Physical Characteristics Of A Highly Fractured Aquifer System To Create Sustainable Use Of Groundwater In A Climate With Projected Drying Trends., Marsha K. Allen

Doctoral Dissertations

Improving the hydrological analysis of groundwater flow paths by integrating geochemical and physical characteristics of a highly fractured aquifer system to create sustainable use of groundwater in a climate with projected drying trends.

Precipitation over Caribbean islands has decreased steadily since the 1950's, which has led to severe drought conditions. The most recent Pan-Caribbean Drought occurred from 2013 to 2016. Climate models predict that drying trends are expected to continue and become more severe over time as precipitation decreases and temperatures rise. In addition, evaporation rates on these islands are expected to increase by ~15-17%, contributing to the drought ...


Stratigraphic And Geochemical Evaluation Of Distal Flows Of The Columbia River Flood Basalts In The Greater Vale Area, Southeastern Oregon, Lena Marie Fox 2022 Portland State University

Stratigraphic And Geochemical Evaluation Of Distal Flows Of The Columbia River Flood Basalts In The Greater Vale Area, Southeastern Oregon, Lena Marie Fox

Dissertations and Theses

Exposures of Columbia River Basalt Group (CRBG) in southeastern Oregon are dominated by the four main phase CRBG units: Steens Basalt, Imnaha Basalt, Grande Ronde Basalt (GRB), and Picture Gorge Basalt (PGB). These units are best seen in stratigraphic sequence along the Malheur Gorge corridor of southeastern Oregon, between the towns of Vale and Juntura, with flows of Steens Basalt from the south overlain by flows of Imnaha and GRB from the north. Recently, PGB flows were found to be part of the eastern Malheur Gorge stratigraphy as well.

In Malheur Gorge, local units of Birch and Hunter Creek Basalt ...


Optimal Bandwidth Selection For Retrieving Cu Content In Rock Based On Hyperspectral Remote Sensing, MA Xiumei, ZHOU Kefa, WANG Jinlin, CUI Shichao, ZHOU Shuguang, WANG Shanshan, ZHANG Guanbin 2022 1 State Key Laboratory of Desert and Oasis Ecology, Xinjiang Institute of Ecology and Geography, Chinese Academy of Sciences, Urumqi 830011, China; 2 Xinjiang Key Laboratory of Mineral Resources and Digital Geology, Xinjiang Institute of Ecology and Geography, Chinese Academy of Sciences, Urumqi 830011, China; 3 Xinjiang Research Centre for Mineral Resources, Xinjiang Institute of Ecology and Geography, Chinese Academy of Sciences, Urumqi 830011, China; 4 University of Chinese Academy of Sciences, Beijing 100049, China

Optimal Bandwidth Selection For Retrieving Cu Content In Rock Based On Hyperspectral Remote Sensing, Ma Xiumei, Zhou Kefa, Wang Jinlin, Cui Shichao, Zhou Shuguang, Wang Shanshan, Zhang Guanbin

Journal of Arid Land

Hyperspectral remote sensing technology is widely used to detect element contents because of its multiple bands, high resolution, and abundant information. Although researchers have paid considerable attention to selecting the optimal bandwidth for the hyperspectral inversion of metal element contents in rocks, the influence of bandwidth on the inversion accuracy are ignored. In this study, we collected 258 rock samples in and near the Kalatage polymetallic ore concentration area in the southwestern part of Hami City, Xinjiang Uygur Autonomous Region, China and measured the ground spectra of these samples. The original spectra were resampled with different bandwidths. A Partial Least ...


Structural And Petrologic Insights Into The Emplacement Of Effusive Silicic Lavas: Inyo Domes, California, Shelby L. Isom 2022 West Virginia University

Structural And Petrologic Insights Into The Emplacement Of Effusive Silicic Lavas: Inyo Domes, California, Shelby L. Isom

Graduate Theses, Dissertations, and Problem Reports

The Long Valley volcanic region, eastern California, USA is most famous for the caldera-forming eruption which produced the Bishop Tuff ~760,000 years ago. Over the last 3,000 years volcanism has been focused in the western margin of the region through punctuated eruptions of silicic lavas and domes. Three simultaneous effusive silicic eruptions, ~600 years ago, generated three lava domes: Obsidian Dome; Glass Creek Dome; and Deadman Dome which erupted onto vastly different topographies. These domes are exceptionally unique as they erupted variable amounts of two textural and chemical endmember lavas (crystal-rich and crystal-poor) that intimately mixed. The overarching ...


Spatial Geochemical Changes In Central And East Texas Soils Over Time Resulting From Human Decomposition, Isabela Marisol Overturf 2022 Claremont McKenna College

Spatial Geochemical Changes In Central And East Texas Soils Over Time Resulting From Human Decomposition, Isabela Marisol Overturf

CMC Senior Theses

Human decomposition is studied to aid forensic investigations and better understand the impact of cemeteries on urban resources like soil and groundwater. The purpose of this study was to identify changes in soil geochemistry at and around a human grave to search for lateral nutrient movement and possibly identify new patterns in elemental concentrations that could be used in estimating post-mortem intervals (PMIs). At the Forensic Anthropology Research Facility (FARF) at Texas State San Marcos, soil samples were collected from a shallow grave over the course of 54 days to conduct analysis for organic matter content, texture, pH, and bulk ...


Mining-Contaminated Sediment And Metal Storage In Channel Deposits In Turkey Creek, Tri-State Mining District, Missouri And Kansas, Max Quinn Hillermann 2022 Missouri State University

Mining-Contaminated Sediment And Metal Storage In Channel Deposits In Turkey Creek, Tri-State Mining District, Missouri And Kansas, Max Quinn Hillermann

MSU Graduate Theses

The Joplin subdistrict, within the Tri-State Mining District (TSMD), was a major producer of lead (Pb) and zinc (Zn) ore between the 1880s to 1920s. Metalliferous mining wastes are still stored in the channel deposits of local streams raising environmental and health concerns. This study quantifies the volume, sediment size, and metal concentrations in channel bed, bar, bench, and chute deposits to quantify the spatial variability of contaminated sediment storage in Turkey Creek (119 km2). Sample reaches (n=14) contained metal concentrations elevated above the Tri-State Mining District specific probable effects concentration at every site with mean concentrations in ...


Distribution Of Particulate Organic Carbon – Fluxes And Inventories – In Growth-Faulted Coastal Wetlands, Samuel Joel Whitehead 2022 University of Kentucky

Distribution Of Particulate Organic Carbon – Fluxes And Inventories – In Growth-Faulted Coastal Wetlands, Samuel Joel Whitehead

Theses and Dissertations--Earth and Environmental Sciences

Coastal wetlands along the Northern Gulf of Mexico (NGOMx) are critically important but threatened environments which provide significant and diverse economic, social, and environmental value. These environments are essential components to the global carbon cycle, serving as one of the most efficient terrestrial carbon sinks. Since onset of the Industrial Revolution increasing rates of coastal wetland loss have been documented due to a variety of anthropogenic activities, neotectonic processes, subsidence, and rising sea-levels. This research utilized an array of methods and sedimentological analyses to test the hypothesis that growth-fault induced changes at Earth’s surface affects the delivery to, and ...


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