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Spatial Variations In Ancient Meteoric Water: An Investigation Of The Rattlesnake Tuff, Julian Michael Cohen 2023 Portland State University

Spatial Variations In Ancient Meteoric Water: An Investigation Of The Rattlesnake Tuff, Julian Michael Cohen

Dissertations and Theses

Volcanic glass has been used extensively as a paleoclimate proxy. Deuterium (2H) concentrations in glass have been found to be stable over geologic timescales, making δD a reliable proxy for ancient water chemistry. However, continued work revolves around better understanding how different factors affect preserved water in ash. Here, I analyze δD in the Rattlesnake Tuff (RST), a widespread ca. 7 Ma ashflow tuff, and create an isoscape to assess variations in δD across Oregon during that time. Additionally, I examine compositional data from glass shards to explore the relationship between δD and shard composition. The RST exhibits well defined …


Hydrology Data For Fern Cave, Alabama (2020-2022), Benjamin Tobin, Benjamin V. Miller, Matthew Niemiller, Andrea Erhardt 2023 University of Kentucky

Hydrology Data For Fern Cave, Alabama (2020-2022), Benjamin Tobin, Benjamin V. Miller, Matthew Niemiller, Andrea Erhardt

Research Data--KGS

Dataset includes water level from four sites within Fern Cave in Jackson County Alabama. Additionally, it includes chemistry of water, sediments and cave-adapted isopods.


Assessing Ecological Relationships Among Late Triassic Vertebrates In Petrified Forest National Park, Alexandra Davis Apgar 2023 University of New Mexico

Assessing Ecological Relationships Among Late Triassic Vertebrates In Petrified Forest National Park, Alexandra Davis Apgar

Earth and Planetary Sciences ETDs

The complex vertebrate ecosystem of the Late Triassic has not yet been fully understood, largely due to oversimplification of hypothesized trophic hierarchies and limited preservation of direct evidence of faunal interaction. Paleocommunity reconstruction attempts can also fall victim to taphonomic biases, time-averaging inaccuracies, and non-analogue paleoecologies. Utilizing a combination of PAIRS analysis and NMDS ordination, we highlight vertebrate faunal relationships within the Adamanian and Revueltian faunachrons of Petrified Forest National Park, assess the likelihood that these patterns have ecological rather than preservational drivers, and examine how these potential interactions may have been impacted by the Adamanian-Revueltian turnover event. We are …


Polygonal Faults In The Austin Chalk: Invariance Of Scale From Mud Cracks To Polygons With Implications Of Structural, Geomorphic And Isotopic Data On Polygonal Fault Geometry And Origin., Kun Shang 2023 Southern Methodist University

Polygonal Faults In The Austin Chalk: Invariance Of Scale From Mud Cracks To Polygons With Implications Of Structural, Geomorphic And Isotopic Data On Polygonal Fault Geometry And Origin., Kun Shang

Earth Sciences Theses and Dissertations

The Cretaceous Austin Chalk contains large numbers of fractures and normal faults whose orientations have been attributed to either regional stresses (e.g., the Balcones fault trend) or, by analogy with the mudrocks, to polygonal faulting resulting from compaction. In this study, we present geomorphic data, field study, and stable isotope data to support that the majority of these faults in North Texas are polygonal. Field-measured fault orientations suggest randomly distributed fault strikes, indicating a polygonal fault structure. Using geomorphologic data (topographic and DEM data) on stream orientations suggests that the polygonal fault patterns are best reflected in the headwater (1st …


Hf Radar: Shining A Light On Ocean Currents, Douglas Cahl 2023 University of South Carolina

Hf Radar: Shining A Light On Ocean Currents, Douglas Cahl

Theses and Dissertations

High Frequency (HF) radar systems are commonly used to estimate surface ocean currents over the coastal ocean. Their range depends on their operational frequency and low frequency systems (≤ 10 MHz) can reach distances up to 200 km from the coastline. These systems are used to estimate surface currents by measuring the phase speed of wind-driven waves and comparing the measured speed with that expected theoretically; deviations from the theoretical still-water phase speed are attributed to ocean surface currents. Although HF radar systems are considered a mature technology and the accuracy of the radar-derived surface current estimates is well studied, …


Effects Of Landslides On Terrestrial Carbon Stocks With A Coupled Geomorphic-Biologic Model: Southeast Alaska, United States, Adam M. Booth, Brian Buma, S. Nagorski 2023 Portland State University

Effects Of Landslides On Terrestrial Carbon Stocks With A Coupled Geomorphic-Biologic Model: Southeast Alaska, United States, Adam M. Booth, Brian Buma, S. Nagorski

Geology Faculty Publications and Presentations

Landslides influence the global carbon (C) cycle by facilitating transfer of terrestrial C in biomass and soils to offshore depocenters and redistributing C within the landscape, affecting the terrestrial C reservoir itself. How landslides affect terrestrial C stocks is rarely quantified, so we derive a model that couples stochastic landslides with terrestrial C dynamics, calibrated to temperate rainforests in southeast Alaska, United States. Modeled landslides episodically transfer C from scars to deposits and destroy living biomass. After a landslide, total C stocks on the scar recover, while those on the deposit either increase (in the case of living biomass) or …


Groundwater Flow And Salt Marsh Migration: The Forest/Marsh Boundary, Camille Rossiello 2023 University of South Carolina

Groundwater Flow And Salt Marsh Migration: The Forest/Marsh Boundary, Camille Rossiello

Theses and Dissertations

Salt marshes migrate landward in response to sea level rise, but the rate of this migration is not constant and can be influenced by pulse disturbances. Long term observations at Sapelo Island, Georgia, show that salt marsh migration has occurred during droughts, but the mechanism for this migration is unclear. Drought is thought to influence salt marsh migration by reducing fresh groundwater discharge from the upland. Rising sea level also encroaches on the upland, which could cause movement of the freshwater lens inland. A two-dimensional numerical model was built to simulate groundwater flow and solute transport based on the Marsh …


Flow Generation And Propagation From Headwater Wetlands To Downstream Waters, Leanne Marie Stepchinski 2023 University of South Florida

Flow Generation And Propagation From Headwater Wetlands To Downstream Waters, Leanne Marie Stepchinski

USF Tampa Graduate Theses and Dissertations

Headwater wetlands are connected to one another and to downstream waters by dynamic hydrologic flowpaths, functioning as integrated hydrologic networks at the watershed scale. Headwater wetlands perform a variety of hydrologic lag, sink, and source functions, including flow generation and propagation, thereby contributing to the natural flow regimes of downgradient waters. The functions of individual wetlands and their contributions to hydrologic connectivity and subsequently to the natural flow regime have been widely studied and are well understood. Comparatively, the functions and hydrologic connectivity within wetland complexes as a whole and their collective subsequent contributions to the natural flow regime of …


Wildlife Ecological Risk Assessment In The 21st Century: Promising Technologies To Assess Toxicological Effects, Barnett A. Rattner, Thomas G. Bean, Val R. Beasley, Philippe Berny, Karen M. Eisenreich, John E. Elliott, Margaret L. Eng, Phyllis C. Fuchsman, Mason D. King, Rafael Mateo, Carolyn B. Meyer, Jason M. O'Brien, Christopher J. Salice 2023 US Geological Survey

Wildlife Ecological Risk Assessment In The 21st Century: Promising Technologies To Assess Toxicological Effects, Barnett A. Rattner, Thomas G. Bean, Val R. Beasley, Philippe Berny, Karen M. Eisenreich, John E. Elliott, Margaret L. Eng, Phyllis C. Fuchsman, Mason D. King, Rafael Mateo, Carolyn B. Meyer, Jason M. O'Brien, Christopher J. Salice

United States Geological Survey: Staff Publications

Despite advances in toxicity testing and the development of new approach methodologies (NAMs) for hazard assessment, the ecological risk assessment (ERA) framework for terrestrial wildlife (i.e., air‐breathing amphibians, reptiles, birds, and mammals) has remained unchanged for decades. While survival, growth, and reproductive endpoints derived from whole-animal toxicity tests are central to hazard assessment, nonstandard measures of biological effects at multiple levels of biological organization (e.g., molecular, cellular, tissue, organ, organism, population, community, ecosystem) have the potential to enhance the relevance of prospective and retrospective wildlife ERAs. Other factors (e.g., indirect effects of contaminants on food supplies and infectious disease processes) …


Applications Of Seismic And Geodetic Data To Earthquake Hazard Research, Mahsa Afra 2023 University of South Florida

Applications Of Seismic And Geodetic Data To Earthquake Hazard Research, Mahsa Afra

USF Tampa Graduate Theses and Dissertations

Being a part of a seismically active zone, including large and crowded cities such asTehran, Qazvin and Semnan, Central Alborz experiences many local earthquakes. Knowl- edge of crustal velocity structure in this area is thus necessary considering its economical and political importance, a large concentration of population, and relatively poor construc- tion practice which increases the earthquake risks in this region. In second chapter of this thesis, we aim at obtaining the 3D crustal velocity structure of the Central Alborz region in northern Iran using local earthquake tomography. We also validate anomalies inferred from our velocity model using an independent …


Marine Anoxia Initiates Giant Sulfur-Bacteria Mat Proliferation And Associated Changes In Benthic Nitrogen, Sulfur, And Iron Cycling In The Santa Barbara Basin, California Borderland, David J. Yousavich, De'Marcus Robinson, Xuefeng Peng, Sebastian J.E. Krause, Frank Wenzhoefer, Felix Janßen, Na Liu, Jonathan Tarn, Frank Kinnaman, David L. Valentine, Tina Treude 2023 University of South Carolina - Columbia

Marine Anoxia Initiates Giant Sulfur-Bacteria Mat Proliferation And Associated Changes In Benthic Nitrogen, Sulfur, And Iron Cycling In The Santa Barbara Basin, California Borderland, David J. Yousavich, De'marcus Robinson, Xuefeng Peng, Sebastian J.E. Krause, Frank Wenzhoefer, Felix Janßen, Na Liu, Jonathan Tarn, Frank Kinnaman, David L. Valentine, Tina Treude

Faculty Publications

The Santa Barbara Basin naturally experiences transient deoxygenation due to its unique geological setting in the southern California Borderland and seasonal changes in ocean currents. Long-term measurements of the basin showed that anoxic events and subsequent nitrate exhaustion in the bottom waters have been occurring more frequently and lasting longer over the past decade. One characteristic of the Santa Barbara Basin is the seasonal development of extensive mats of benthic nitrate-reducing sulfur-oxidizing bacteria, which are found at the sediment–water interface when the basin's bottom waters reach anoxia but still provide some nitrate. To assess the mat's impact on the benthic …


Sedimentary Processes And Instability On The Mississippi River Delta Front Near The Wreck Of The Ss Virginia, Nathan Figueredo 2023 Louisiana State University

Sedimentary Processes And Instability On The Mississippi River Delta Front Near The Wreck Of The Ss Virginia, Nathan Figueredo

LSU Doctoral Dissertations

Multi-cores and piston cores were collected seaward of the Mississippi River Delta’s Southwest Pass at ~80 m water depth in 2017 to better understand sedimentary characteristics and processes on the Mississippi River Delta Front (MRDF) in the vicinity of the SS Virginia shipwreck, and to support marine archeological research. Core analyses were performed to inform our understanding of the dynamics of sediment motion in the study area through radionuclide activity (210Pb and 137Cs), volume frequency of grain size, bulk density, and fabric (X-Radiography). Sediment accumulation rates (SAR), calculated from multi-core 210Pb activity are 0.22 - 0.29 …


Managing Water Quality To Enable Future Irrigation Development In The Kimberley Region, Department of Primary Industries and Regional Development, Western Australia 2023 Department of Primary Industries and Regional Development, Western Australia

Managing Water Quality To Enable Future Irrigation Development In The Kimberley Region, Department Of Primary Industries And Regional Development, Western Australia

Natural resources commissioned reports

Three-Dimensional Hydrodynamic Modelling to Evaluate the Effect of Farm Chemicals on the Lower Pools of the Keep River

The National Water Grid Authority awarded the Department of Primary Industries and Regional Development (DPIRD) a project entitled ‘Managing Water Quality to Enable Future Irrigation Development in the Kimberley Region’.

The purpose of the project is to review the current and future risk profile of agrichemicals (pesticides) in the Keep River catchment (Ord - East Kimberley) in the context of irrigation development across the last decade and proposed in the medium term. The results of the review were to define prospective mitigation …


Preliminary Data Of Potentially Hazardous Radon Concentrations In Modrič Cave (Croatia), Robert Lončarić, Vanja Radolić, Maša Surić, Igor Miklavčić, Matea Šatalić, Dalibor Paar, Lukrecija Obšivač 2023 Department of Geography, University of Zadar, Croatia

Preliminary Data Of Potentially Hazardous Radon Concentrations In Modrič Cave (Croatia), Robert Lončarić, Vanja Radolić, Maša Surić, Igor Miklavčić, Matea Šatalić, Dalibor Paar, Lukrecija Obšivač

International Journal of Speleology

Instigated by relatively high cave-air CO2 concentrations in Modrič Cave (Croatia) recorded for the purpose of speleothem-based paleoclimate research, we established preliminary monitoring of radon (222Rn) concentrations within the cave for a 4.5-year period (2018–2022). As radioactive geogenic gas, radon, which often correlates with cave-air CO2 concentrations, presents a potential health hazard in cases of longer exposure time in high concentration conditions. Since the Modrič Cave is open to tourists and long-term scientific research has been performed within, a safety assessment for radon concentrations was essential. The integrated measurements of radon concentrations were performed by passive …


Wast3d Potential, Andrew Larsen 2023 Rhode Island School of Design

Wast3d Potential, Andrew Larsen

Masters Theses

Waste is obsolete. Standard building industry practices are harmful to the environment. Non-traditional construction methods were examined as alternatives. Circular design logic was the guiding principle in material choice. Additive manufacturing is a proven modern method for building construction. Research on 3D printing case studies revealed that recycled plastic is a proven material and readily available. Removing plastic waste from the environment and sequestering it in architectural components gives the material a new purpose. The component of focus was a building block for a wall assembly. Inspiration was taken from the hexagonal Basalt rock formations found near volcanic fault lines. …


Unearthing Complexity: Tangible Histories Of Water And Earth, Alexis Violet 2023 Rhode Island School of Design

Unearthing Complexity: Tangible Histories Of Water And Earth, Alexis Violet

Masters Theses

Unearthing Complexity investigates conceptions of time and surface through geological stories of the water and earth. Building on theories of deep time, hydrofeminism, critical zones, and grounding, I hope to foster a deeper awareness of time scales other than our own and a more tangible understanding of the embodied experience of matter in the universe. Working toward a new literacy of the water and earth in which they are recognized as living, changing bodies to which we are inherently tied at a molecular level, the site of this multiscalar inquiry occurs in the coastal zones of the Narragansett Bay where …


Western Kentucky University Stormwater Utility Survey 2023, Warren Campbell, Emily G. Davis 2023 Western Kentucky University

Western Kentucky University Stormwater Utility Survey 2023, Warren Campbell, Emily G. Davis

SEAS Faculty Publications

The main goal of this survey is to identify as many U.S. Stormwater Utilities (SWUs) as possible. Because many stormwater professionals do not have the time to respond to questionnaires, our primary method of identification was Internet searches. We searched key terms such as “stormwater utility”, “stormwater fee”, and “drainage fee”. We scoured online municipal codes such as Municode, AmLegal, Sterling, LexisNexis, General Code, and others. We searched through many city web websitesing to find utilities. We have also had many people contact me to update fees and identify new utilities. However, the data primarily comes from Internet sources and …


Using Two Coeval Andesites From Middle Sister And South Sister, Oregon, As Clues To Understanding Connectivity Between Adjacent, Coincident Stratovolcanoes, James Peale 2023 Western Washington University

Using Two Coeval Andesites From Middle Sister And South Sister, Oregon, As Clues To Understanding Connectivity Between Adjacent, Coincident Stratovolcanoes, James Peale

Geology Graduate and Undergraduate Student Scholarship

The Three Sisters Volcanic Complex in central Oregon is a cluster of three primary stratovolcanoes and a mafic periphery which lies at the intersection of the Cascade volcanic arc and the Basin and Range extensional province. This project focuses on the two youngest stratovolcanoes, Middle Sister and South Sister. Middle Sister experienced a period of frequent eruptive activity from approximately 27 ka to 14 ka, during which it erupted dacites, andesites, and basaltic andesites. South Sister experienced an intense period of eruptive activity from approximately 36 ka to 22 ka, during which it erupted a diverse suite of magmas ranging …


Understanding Potential Reservoir Interconnectivity Between Two Contemporaneous Volcanoes During The Onset Of Cone-Building Activity, Middle Sister And South Sister, Central Oregon, Emma Calvert 2023 Western Washington University

Understanding Potential Reservoir Interconnectivity Between Two Contemporaneous Volcanoes During The Onset Of Cone-Building Activity, Middle Sister And South Sister, Central Oregon, Emma Calvert

Geology Graduate and Undergraduate Student Scholarship

Klah Klanee (Three Points) is located in the central Cascades near Bend, Oregon. The Three Sisters Volcanic Complex (TSVC) lies at a tectonically complex intersection of the Cascade Subduction Zone, the Basin and Range Province, and the High Lava Plains. The TSVC is a compositionally diverse volcanic field consisting of four stratovolcanoes and numerous periphery cones and vents. Middle Sister and South Sister are the youngest of the stratovolcanoes and they share a largely contemporaneous and semi-alternating episodic eruptive history. These parallel histories could indicate a complex, interconnected magmatic root system within the crust below the TSVC and the surrounding …


Untangling The Nature And Timescales Of Magmatic Processes Driving Eruptions At Quiescent Volcanoes: Examples From Momotombo, Nicaragua, And Cumbre Vieja, Canary Islands, Samantha Tramontano 2023 The Graduate Center, City University of New York

Untangling The Nature And Timescales Of Magmatic Processes Driving Eruptions At Quiescent Volcanoes: Examples From Momotombo, Nicaragua, And Cumbre Vieja, Canary Islands, Samantha Tramontano

Dissertations, Theses, and Capstone Projects

Across all scales of human relationships (i.e. person-to-person, country-to-country, etc.), qualms can take the form of long-standing wars, quick and intense bouts, or petty exchanges. While our understanding of human behavior is ever increasing, reactions and behaviors of self and others may still come as a surprise. Expressions of disagreement can occur suddenly or following years to centuries of accumulated grievances. The solid earth is also a system that behaves (like human emotion) predictably at times and unpredictably at other times. Some volcanoes, a tangible surface expression of solid earth processes, exhibit precursory signals prior to eruption (e.g. the bulging …


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