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Geochemical Assessment Of Sediment Flux In A Sediment Core From A Tidal Flat In A Tropical Estuary, Olumide Ajulo 2025 Fort Hays State University

Geochemical Assessment Of Sediment Flux In A Sediment Core From A Tidal Flat In A Tropical Estuary, Olumide Ajulo

Master's Theses or Doctor of Nursing Practice

Sediment flux in estuaries is influenced by both natural processes and anthropogenic activities. Understanding the historical and current trends in sediment flux inputs and geochemical composition are essential for evaluating the estuary’s response to natural and human-induced changes and for developing effective environmental management strategies. The tropical Wouri Estuary in Cameroon receives water and sediment inputs from three main rivers draining urban, industrial, and agricultural areas, as well as different rock terrains. The complex inputs into the estuary can significantly affect sediment flux, consequently impacting the ecosystem. Thereby making an understanding of the temporal variations in sediment inputs in the …


Characterization And Leaching Feasibility Studies Of Copper Flue Dust For The Recovery Of Main And Trace Metals, Fardis Nakhaei, Marek Locmelis, Lana Alagha, Michael S. Moats, Carlos Eyzaguirre, Cory Smith 2025 Missouri University of Science and Technology

Characterization And Leaching Feasibility Studies Of Copper Flue Dust For The Recovery Of Main And Trace Metals, Fardis Nakhaei, Marek Locmelis, Lana Alagha, Michael S. Moats, Carlos Eyzaguirre, Cory Smith

Geosciences and Geological and Petroleum Engineering Faculty Research & Creative Works

Although copper smelter dust (CSD) is classified as hazardous waste, it also serves as a valuable secondary resource, offering potential for the recovery of critical elements. In this study, CSD samples were collected from the waste heat boiler (WHB) and electrostatic precipitator (ESP) units connected to the flash smelting furnace at a copper smelter. The representative samples were extensively characterized by particle size, and chemical and mineralogical analyses. Following sample characterization, leaching experiments were performed to evaluate the potential extraction of Cu, Fe, As, Zn, Pb, In, Ga, and Ge from the flue dusts. Distilled water, H2SO4, and HCl were …


Hydrogeochemical Characterization Of The Ahtanum Alluvial Fan For Managed Aquifer Recharge, Yakima Basin, Washington, Brook M. Bauer 2025 Central Washington University

Hydrogeochemical Characterization Of The Ahtanum Alluvial Fan For Managed Aquifer Recharge, Yakima Basin, Washington, Brook M. Bauer

All Master's Theses

Overallocation of water resources in the Yakima River Basin, central Washington, has prompted investigation into facilitated aquifer recharge to enhance water supply during drought as part of the Yakima Basin Integrated Plan (YBIP). This study evaluates and characterizes the recharge potential of the Ahtanum Creek alluvial fan within the lower Ahtanum Sub-Basin by integrating geologic, hydraulic, and geochemical data.

Four main hydrogeologic units (unconsolidated, semi-consolidated, consolidated basin-fill deposits, and Columbia River Basalt aquifers) were identified from stratigraphic analysis of well logs across seven transects spanning the active fan and abandoned alluvial terrace portions of the alluvial fan study area. Stable …


Origins And Mechanisms Of Mobility Of Geogenic Arsenic Contamination In Toutle And Silver Lake, Wa, Usa, William A. Hays 2025 Central Washington University

Origins And Mechanisms Of Mobility Of Geogenic Arsenic Contamination In Toutle And Silver Lake, Wa, Usa, William A. Hays

All Master's Theses

Arsenic (As), a common contaminant in groundwater, is toxic to human health and has a maximum contaminant level of 10 ppb set by both the World Health Organization and the U.S. Environmental Protection Agency (ATSDR, 2007). In Toutle, WA, USA (30 km west of Mount Saint Helens), a private well, labelled TOU1, was previously identified with ~670 ppb of As and was the impetus of this study. This study targeted private wells in the vicinity of TOU1 to identify the extent of the arsenic contamination, identify the aquifer(s) of concern, and identify the mechanism(s) of mobility.

The wells were screened …


Zircon Age And Oxidation State Estimates For Plutons Spatially Associated With Mineral Deposits Along The Kettle Detachment Fault In The Orient Quadrangle, Northeastern Washington, Karla Ortega 2025 Central Washington University

Zircon Age And Oxidation State Estimates For Plutons Spatially Associated With Mineral Deposits Along The Kettle Detachment Fault In The Orient Quadrangle, Northeastern Washington, Karla Ortega

All Master's Theses

Critical minerals are essential to national security, economic stability, and the transition to clean energy, making them a priority in geologic research and exploration. To better understand the magmatic conditions associated with critical mineral concentration, zircon, a recorder of magmatic history, was analyzed using U-Pb geochronology and trace element geochemistry. The analyses were conducted via LASS-ICP-MS on ten plutonic samples from the Orient quadrangle in northeastern Washington and one sample from the Adams Mountain and Hunter (AMH) quadrangles to constrain the geological processes leading to ore deposit formation, including tungsten (W). This region, cut by the Kettle Detachment fault, is …


Applying Multi-Method P-T Estimation Techniques To Constrain Deep Crustal Tectonic Processes: An Example From Hp Granulites North Qaidam Terrane, China, James A. Anderson 2025 Central Washington University

Applying Multi-Method P-T Estimation Techniques To Constrain Deep Crustal Tectonic Processes: An Example From Hp Granulites North Qaidam Terrane, China, James A. Anderson

All Master's Theses

High pressure (HP) granulites form within collisional and subduction zone tectonic environments. Due to high temperature and presence of melt, it is difficult to recover their pressure and temperature (P-T) history by conventional methods. An integration of multi-method P-T estimations provides insight on these deep crustal processes.

We apply petrographic analysis, Zr-in-Rt thermometry, phase equilibria modeling, and conventional thermobarometric calculations to constrain metamorphic conditions of Early Paleozoic HP granulite samples formed during late stage continental subduction/collision from the North Qaidam terrane.

HP granulites contain the mineral assemblage Grt + Pl ± Cpx + Qtz + Ky + Rt ± Czo. …


Evaluation Of Practical Methods To Determine If A Karst Creek Is Gaining Or Losing: Case Study Of Leith Creek, Elizabeth Jones 2025 Missouri State University

Evaluation Of Practical Methods To Determine If A Karst Creek Is Gaining Or Losing: Case Study Of Leith Creek, Elizabeth Jones

Graduate Theses/Dissertations

Karst landscapes are abundant in Missouri, with features such as caves, springs, and sinkholes that form through the dissolution of limestone. Leith Creek is a small stream in Polk County, Missouri fed by two springs and the shallow unconfined Springfield Plateau aquifer, a highly karstified aquifer which is made up of limestone and minor interbedded shale-mudstone units. To determine if Leith Creek is gaining or losing, stream flow, water chemistry and temperature sensors were monitored. Stream flow results required multiple visits to take measurements while temperature sensors required two visits, one to install the dataloggers and another to remove the …


Oil-Oil Correlation Across Sedimentary Basins In Kansas Using Molecular Geochemistry And Fourier Transform Infrared Spectroscopy, Oluwaseun V. Omoyemi 2025 Fort Hays State University

Oil-Oil Correlation Across Sedimentary Basins In Kansas Using Molecular Geochemistry And Fourier Transform Infrared Spectroscopy, Oluwaseun V. Omoyemi

Master's Theses or Doctor of Nursing Practice

Hydrocarbons are produced from different subbasins and stratigraphic intervals in Kansas. However, the geochemical characteristics and sources of these hydrocarbons are still poorly understood. While reservoir rocks, seals, and traps that are essential for petroleum systems are well defined within the state, the possible source rocks are often considered thermally immature, raising questions about their ability to generate the volume of hydrocarbons currently being produced. This research project tries to evaluate the geochemical characteristics of hydrocarbons produced in the state of Kansas and determine if the hydrocarbons from the different subbasins and stratigraphic units are genetically related. Thirty-seven crude oil …


Molecular Characterization Of Humic And Fulvic Acids On Watterlogged And Well-Drained Amazonian Podzols, Amanda M. Tadini, Aleksandar I. Goranov, Stéphane Mounier, Débora M.B.P. Milori, Célia R. Montes, Patrick G. Hatcher 2025 Old Dominion University

Molecular Characterization Of Humic And Fulvic Acids On Watterlogged And Well-Drained Amazonian Podzols, Amanda M. Tadini, Aleksandar I. Goranov, Stéphane Mounier, Débora M.B.P. Milori, Célia R. Montes, Patrick G. Hatcher

Chemistry & Biochemistry Faculty Publications

The Amazon rainforest is the largest tropical rainforest in the world. Amazonian Podzol soils, characteristic of this region, are known to store substantial amounts of organic carbon in both their surface and deep horizons. Despite decades of research, the molecular-level composition of these soils remains uncharacterized. This study addresses this knowledge gap by employing ultrahigh resolution mass spectrometry, namely, Fourier transform–ion cyclotron resonance–mass spectrometry (FT-ICR-MS), to determine the molecular composition of humic acid (HA) and fulvic acid (FA) fractions from two Amazonian Podzol profiles of varying levels of groundwater exposure (waterlogged vs well-drained). In the waterlogged soil compounds containing nitrogen, …


Oxidation Camouflages Terrestrial Organic Matter To Appear Marine-Like, Aleksandar I. Goranov, Susan J. Carter, Ann Pearson, Patrick G. Hatcher 2025 Old Dominion University

Oxidation Camouflages Terrestrial Organic Matter To Appear Marine-Like, Aleksandar I. Goranov, Susan J. Carter, Ann Pearson, Patrick G. Hatcher

Chemistry & Biochemistry Faculty Publications

The export of terrestrial organic matter (TOM) to the ocean has been traditionally viewed to be minimal or only of significance in near-coastal continental margins. The broadly accepted explanation for the widespread loss of terrestrial lignin biomarkers and apparent disappearance of the <-25‰ stable carbon isotopic signature (δ¹³C) of TOM is that TOM is almost fully degraded before reaching the open ocean. Oceanic carbon (δ¹³C value ≥ -22‰) is therefore thought to be derived primarily from algae. However, an alternative explanation for the different molecular and δ¹³C signatures in terrestrial and marine environments may be that oxidative processing transforms TOM to appear marine-like. To test this hypothesis, we subjected eight TOM samples to a strong oxidation gradient. At carbon losses typical of TOM degradation during transport and sedimentation (above 60%), the differentiators of provenance disappeared, leaving a residue that was marine-like both chemically (aliphatic- and nitrogen-rich) and isotopically (δ¹³C enrichment of 4 to 9‰). This challenges the validity of conventional two-endmember mixing models, suggesting that a much larger fraction than previously estimated of the organic matter found in the ocean may originate from terrestrial sources, impacting global models of carbon cycling and sequestration.


Core-Top Constraints On The Ecology And Paleothermometry Of Planktic Foraminifera In The Indian Ocean, Ryan H. Glaubke, Elisabeth L. Sikes, Natalie E. Umling, Katherine A. Allen, Matthew W. Schmidt 2025 Rutgers University - New Brunswick/Piscataway

Core-Top Constraints On The Ecology And Paleothermometry Of Planktic Foraminifera In The Indian Ocean, Ryan H. Glaubke, Elisabeth L. Sikes, Natalie E. Umling, Katherine A. Allen, Matthew W. Schmidt

OES Faculty Publications

The magnesium-to‑calcium ratio (Mg/Ca) of fossil foraminifera is a widely used geochemical proxy for reconstructing past ocean temperatures. Culturing experiments have shown that, for some species, nonthermal influences like salinity and carbonate chemistry play a non-trivial role in the incorporation of Mg into foraminiferal calcite. Inclusion of these variables into Mg/Ca calibrations have provided a better fit to core top and sediment trap data in some recent studies, but the widespread covariation of potential control variables in the open ocean and the lack of multivariate calibrations for some species warrants additional work. Here, we assess Mg/Ca calibrations for four common …


Cropsync: Ai-Powered Sustainable Crop Management, Ziad Doughan, Ibrahim Mneimneh, Zouheir Nakouzi, Noor Al Khaib, Samer Damaj, Jamal Chaaban, Hamza Mrad, Sari Itani 2024 Assistant Professor, Faculty of Engineering, Beirut Arab University, Beirut, Lebanon

Cropsync: Ai-Powered Sustainable Crop Management, Ziad Doughan, Ibrahim Mneimneh, Zouheir Nakouzi, Noor Al Khaib, Samer Damaj, Jamal Chaaban, Hamza Mrad, Sari Itani

BAU Journal - Science and Technology

CropSync is a smart agriculture system that uses AI and IoT technologies to enable sustain- able crop management and precision farming. The system aims to address the challenges faced by the agriculture sector, such as increasing food production to meet global population demands while minimizing environmental impact. CropSync integrates sensors, cameras, and cloud-based analytics to provide farmers with real-time insights and recommendations for optimizing crop cul- tivation. The system upholds engineering professional and ethical standards, considering broader social, environmental, and economic implications. From a social perspective, CropSync improves food security and enhances farmers’ livelihoods through increased productivity and efficient re- …


Evaluating The Usefulness Of Geochronometers In The Packsaddle Domain For Refining The Timing Of Metamorphism Via High-Resolution Petrography, Enchanted Rock State Natural Area, Llano Uplift, Texas, Haylee Vike 2024 Stephen F. Austin State University

Evaluating The Usefulness Of Geochronometers In The Packsaddle Domain For Refining The Timing Of Metamorphism Via High-Resolution Petrography, Enchanted Rock State Natural Area, Llano Uplift, Texas, Haylee Vike

Electronic Theses and Dissertations

The Llano uplift, central Texas, exhumes Mesoproterozoic rocks with a complex history of metamorphism, deformation, and magmatism. There are three recognized metamorphic events related to the Grenville orogeny (~1.3-0.9 Ga). The timing of these metamorphic events is not well resolved due to past methods, technology, and lack of published geologic context for many of the current dates. These current time constraints on metamorphic timing could be further refined through modern geochronologic and petrochronologic methods.

A majority of U-Pb zircon dates from the Valley Spring (~1366-1232 Ma), Coal Creek (~1326-1275 Ma), and Packsaddle (~1257-1215 Ma) domains are interpreted as crystallization ages …


Are There Neurological Impacts Of Exposure To A Burned Wildfire Site As It Recovers?, Rubye Strickland 2024 University of San Diego

Are There Neurological Impacts Of Exposure To A Burned Wildfire Site As It Recovers?, Rubye Strickland

Undergraduate Honors Theses

Wildfires are increasing with climate change, making the human health implications of exposure to burned soils an essential area of research. Metals associated with fire-impacted soils can be inhaled or accidentally ingested by surrounding communities, causing health risks. Several studies have evaluated the health impact of wildfires, but few have done so from a neurological perspective. This study explores metal changes in burned soils over time as a site naturally recovers from wildfire and how these changes may impact human neurological health. Soil samples were collected from the burned area 0, 3, 6, 9, and 12 months after the fire. …


Biogeochemical Controls Of Cesium-137 Migration In Surface Waters And Near Surface Sediments At The Usdoe Savannah River Site, Reid Williams 2024 Clemson University

Biogeochemical Controls Of Cesium-137 Migration In Surface Waters And Near Surface Sediments At The Usdoe Savannah River Site, Reid Williams

All Dissertations

Considerable concentrations of cesium-137 (137Cs) and other anthropogenic radionuclides have been released into the environment at the Savannah River Site (SRS). Additionally, cesium-containing radioactive waste will be stored onsite for the foreseeable future. Therefore, the goal of this work was to identify mechanisms controlling cesium transport in surface waters and near surface sediments at SRS to further the understanding of 137Cs migration in the vadose zone and reservoirs. It was hypothesized that a multitude of factors impact the mobility of 137Cs at the SRS, but that the clay sediment fraction provides an important contribution in limiting …


Evidence For Subsidence Rate Variation In The Newark Basin And Its Influence On The Deposition Of Fluvial Sediments Of The Stockton Formation, Jane L. Alexander, Sean T. Thatcher, Jay Tobon, Victoria Rivelli 2024 CUNY College of Staten Island

Evidence For Subsidence Rate Variation In The Newark Basin And Its Influence On The Deposition Of Fluvial Sediments Of The Stockton Formation, Jane L. Alexander, Sean T. Thatcher, Jay Tobon, Victoria Rivelli

Publications and Research

The Stockton Formation of the Newark Basin represents an exciting time in Earth history during the early stages of rifting of the North Atlantic, with rapid subsidence and sediment deposition. Much of the previous work on this formation has been done using drill cores, with development limiting surface exposure. While this allows us to build a full stratigraphic sequence of deposition, it has the potential to miss smaller-scale variability and sedimentary structures. It is also difficult to understand the three-dimensional geometries, architecture and relationships between the depositional elements from drill core alone. An outcrop in North Bergen, NJ that was …


Comparison Of Soil Organic Matter Fractions In Non-Grazed And Prescribed Sheep-Grazed Managed Land In Southwest Michigan, Julia M. Shreve, Katelyn Smith, Lauren Burns 2024 Grand Valley State University

Comparison Of Soil Organic Matter Fractions In Non-Grazed And Prescribed Sheep-Grazed Managed Land In Southwest Michigan, Julia M. Shreve, Katelyn Smith, Lauren Burns

Student Summer Scholars Manuscripts

The impact of prescribed sheep grazing on soil organic carbon (SOC) was investigated by comparing a 2-acre grazed and a 2-acre non-grazed (control) portion of redeveloped land previously seeded with pasture mix in Southwest Michigan. This study aimed to measure changes in SOC resulting from prescribed sheep grazing by examining two key soil organic matter (SOM) fractions: particulate organic matter (POM) and mineral-associated organic matter (MAOM) along with soil physical and chemical properties (e.g., bulk density, infiltration rate, moisture content, pH, conductivity). Soil cores were collected from 5 locations within each of the 2-acre plots using a diagonal random sampling …


Manifestations Of Sulfuric Acid Speleogenesis In The Mulapampa Travertine, Central Andes Of Peru: Evidence From The Gruta Con Lago, Andrzej Tyc, Krzysztof Gaidzik, Justyna Ciesielczuk, Katarzyna Wątor 2024 Institute of Earth Sciences, Faculty of Natural Sciences, University of Silesia in Katowice, Poland

Manifestations Of Sulfuric Acid Speleogenesis In The Mulapampa Travertine, Central Andes Of Peru: Evidence From The Gruta Con Lago, Andrzej Tyc, Krzysztof Gaidzik, Justyna Ciesielczuk, Katarzyna Wątor

International Journal of Speleology

Sulfuric acid speleogenesis (SAS) is a form of hypogene speleogenesis characterized by the formation of caves in carbonate rocks due to the presence of sulfuric acid. This study focuses on the Gruta con Lago, one of three caves identified in the Mulapampa travertine, located in the central Andes of Peru. These caves are accessed through collapse sinkholes, and much of their morphology results from roof breakdown. The bottom of the studied cave is situated at the current water table. Despite the absence of typical solutional features associated with SAS caves, mineralogical and geochemical evidence of speleogenesis involving H2SO …


Investigation Of Temperature, Solution Strength, And Applied Stress Effects On Cation Exchange Processes In Different Geosynthetic Clay Liner Products, Kendra Fuller 2024 California Polytechnic State University, San Luis Obispo

Investigation Of Temperature, Solution Strength, And Applied Stress Effects On Cation Exchange Processes In Different Geosynthetic Clay Liner Products, Kendra Fuller

Master's Theses

An extensive laboratory test program was conducted to analyze and compare the cation exchange processes in three different varieties of sodium bentonite (Na-B) geosynthetic clay liners (GCLs) over increased conditioning durations up to 32 days and investigate the effects of temperature, solution strength, and applied stress. The goal of this test program was to establish whether the variables of temperature, solution strength, and applied stress improved or degraded the engineering properties of GCLs in laboratory testing and municipal solid waste (MSW) landfill applications. The GCLs were conditioned in liquids of increasing ionic strength, using deionized water and 2, 50, and …


Hypogenic Caves Of Syracuse Area, Sicily (Italy): Geomorphological Evidence Of Co2 Degassing, Fresh-Salt Water Mixing, And Late Condensation Corrosion, Philippe Audra, Jean-Yves Bigot, Didier Cailhol, Pierre Camps, Ilenia M. D'Angeli, Hai Cheng, R. Lawrence Edwards, Fernando Gàzquez-Sanchez, Gabriella Koltai, Giuliana Madonia, Jean-Claude Nobécourt, Marjan Temovski, Marco Vattano, Jo De Waele 2024 Polytech’Lab - UPR 7498, Polytech Nice Sophia, Université Côte d'Azur , 930 route des Colles, 06903 Sophia-Antipolis, France

Hypogenic Caves Of Syracuse Area, Sicily (Italy): Geomorphological Evidence Of Co2 Degassing, Fresh-Salt Water Mixing, And Late Condensation Corrosion, Philippe Audra, Jean-Yves Bigot, Didier Cailhol, Pierre Camps, Ilenia M. D'Angeli, Hai Cheng, R. Lawrence Edwards, Fernando Gàzquez-Sanchez, Gabriella Koltai, Giuliana Madonia, Jean-Claude Nobécourt, Marjan Temovski, Marco Vattano, Jo De Waele

International Journal of Speleology

Many caves in Sicily have been shown to have a sulfuric acid or other hypogenic origin. We studied three caves (Palombara, Scrivilleri, Monello) near Syracuse (eastern Sicily), in an area that was strongly uplifted and faulted, creating multiple Pleistocene marine terraces. Mineralogy, stable isotopes and dating methods (paleomagnetism, U/Th) were used to characterize cave sediments, some of which were related to the initial hypogenic phase (Fe and Mn oxides, calcite spar), others were introduced by surface runoff later. Many other sediments are the result of in situ weathering, such as lime sands produced by condensation-corrosion processes on the calcarenite walls. …


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