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Seismic Analysis Of The Upper & Lower Falls Of The Yellowstone River, Loring Schaible
Seismic Analysis Of The Upper & Lower Falls Of The Yellowstone River, Loring Schaible
Earth and Planetary Sciences ETDs
Twelve years of concurrent hydrologic and continuous seismic data along with temporary seismic data demonstrate that the Upper and Lower Falls of the Grand Canyon of the Yellowstone River comprise a highly localized source of 0.5-5 Hz seismic energy that overwhelms anthropogenic contributions. In aggregate, seismic amplitude from 2008-2019 is linearly related to discharge with a correlation coefficient of 0.96. Repeated deviations from this linear relationship persist for 1-2 weeks prior to the date that Yellowstone Lake becomes clear of winter ice coverage. Seismic efficiency increases by ~50-250% during this period of ice-breakup, during which lake ice flows into the …
The Temporal Evolution Of Subduction Initiation In The Samail Ophiolite: High-Precision U–Pb Zircon Petrochronology Of The Metamorphic Sole, Matthew Rioux, Joshua M. Garber, Michael Searle, James L. Crowley, Sally Stevens, Mark Schmitz, Andrew Kylander-Clark, Kayla Leal, Tyler Ambrose, Andrew J. Smye
The Temporal Evolution Of Subduction Initiation In The Samail Ophiolite: High-Precision U–Pb Zircon Petrochronology Of The Metamorphic Sole, Matthew Rioux, Joshua M. Garber, Michael Searle, James L. Crowley, Sally Stevens, Mark Schmitz, Andrew Kylander-Clark, Kayla Leal, Tyler Ambrose, Andrew J. Smye
Geosciences Faculty Publications and Presentations
High-precision dating of the metamorphic sole of ophiolites can provide insight into the tectonic evolution of ophiolites and subduction zone processes. To understand subduction initiation beneath a young, well-preserved and well-characterized ophiolite, we performed coupled zircon laser-ablation inductively coupled mass spectrometry trace element analyses and high-precision isotope dilution-thermal ionization mass spectrometry U–Pb dating on 25 samples from the metamorphic sole of the Samail ophiolite (Oman-United Arab Emirates). Zircon grains from amphibolite- to granulite-facies (0.8–1.3 GPa, ~700–900°C), garnet- and clinopyroxene-bearing amphibolite samples (n = 18) show systematic trends of decreasing heavy rare earth element slope (HREE; Yb/Dy) with decreasing Yb …
Uav-Based Quantification Of Dynamic Lahar Channel Morphology At Volcán De Fuego, Guatemala, Jerry C. Mock, Jeffrey B. Johnson, Armando Pineda, Gustavo Bejar, Amilcar Roca
Uav-Based Quantification Of Dynamic Lahar Channel Morphology At Volcán De Fuego, Guatemala, Jerry C. Mock, Jeffrey B. Johnson, Armando Pineda, Gustavo Bejar, Amilcar Roca
Geosciences Faculty Publications and Presentations
This study quantified erosional and depositional processes for secondary lahars in Las Lajas drainage at Volcán de Fuego, Guatemala, during the rainy season from May to October 2021. Abundant pyroclastic material from ongoing eruptive activity is remobilized seasonally during heavy precipitation, which can impact infrastructure and populations living near Fuego. Our region of focus was in an agricultural zone 6 to 10 km from the summit, surveyed with an unoccupied aerial vehicle (UAV) quadcopter at monthly intervals. Imagery was processed into overlapping time-lapse structure from motion digital elevation models (DEMs). DEMs were differenced to find volumetric changes as a function …
Revisiting The Diffuse Layer Polarization Of A Spherical Grain In Electrolytes With Numerical Solutions Of Nernst-Planck-Poisson Equations, Qifei Niu
Geosciences Faculty Publications and Presentations
Induced polarization (IP) has been frequently used in solid earth geophysics, hydrology, and environmental sciences. A mechanistic understanding of the IP responses of geological materials is crucial for correctly interpreting field IP measurements. In this study, the fully-coupled, nonlinear Nernst-Planck-Poisson equations are numerically solved to analyze the electrochemical mechanism of diffuse layer polarization around a spherical grain immersed in electrolytes. The numerical results show diffuse layer polarization is formed by the charge separation between counterions in the diffuse layer and charges on the grain surface. Both tangential and normal movements of counterions in the diffuse layer are involved in the …
Whitewater Sound Dependence On Discharge And Wave Configuration At An Adjustable Wave Feature, Taylor A. Tatum, Jacob F. Anderson, Timothy J. Ronan
Whitewater Sound Dependence On Discharge And Wave Configuration At An Adjustable Wave Feature, Taylor A. Tatum, Jacob F. Anderson, Timothy J. Ronan
Geosciences Faculty Publications and Presentations
Stream acoustics has been proposed as a means of monitoring discharge and wave hazards from outside the stream channel. To better understand the dependence of sound on discharge and wave characteristics, this study analyzes discharge and infrasound data from an artificial wave feature which is adjusted to accommodate daily changes in recreational use and seasonal changes in irrigation demand. Monitorable sound is only observed when discharge exceeds ∼35 m3/s, and even above that threshold the sound-discharge relationship is non-linear and inconsistent. When sound is observed, it shows consistent dependence on wave type within a given year, but the …
Quantifying Local And Regional Effects Of Human Development On Centennial Barrier Island Evolution : Insights From Barnegat Inlet, New Jersey, Shane Nichols-O’Neill
Quantifying Local And Regional Effects Of Human Development On Centennial Barrier Island Evolution : Insights From Barnegat Inlet, New Jersey, Shane Nichols-O’Neill
Theses, Dissertations and Culminating Projects
Societal benefits and ecosystem services provided by barrier islands are at risk as these landforms evolve rapidly in response to system changes including an increasing rate of sea-level rise and changing storm patterns. To prevent retreat or drowning, the expected response of natural barrier islands, and preserve benefits provided by barrier islands, significant investments are made at developed barrier islands to stabilize ocean and bay shorelines. Maintaining stable shorelines may not be sustainable in the future due to changing environmental, financial, and political conditions. Decadal to centennial-scale alongshore barrier island evolution at Long Beach Island, New Jersey is analyzed to …
Measurement Of Microplastics In A Freshwater Micro-Watershed, Cole Bowman
Measurement Of Microplastics In A Freshwater Micro-Watershed, Cole Bowman
All Theses
The role of microplastics as an emerging contaminant can be complex to study because of the lack of standardization in the collection and analysis of microplastic particles. The purpose of this manuscript is to detail an iterative process of different collection methods in trying to understand microplastic deposition and transport in a freshwater micro-watershed through lab-based and field-based studies. A flume experiment was conducted to test the trapping efficiency of a sediment trap design at two different velocities (1.12 m/s and 2.24 m/s). Eight types of microplastics varying in morphology and density were introduced to the flume in order to …
High P-T Single Crystal Elasticity Of Zircon And Its Implications For Determining Metamorphic P-T Conditions In Nature, Arlacee Luu
Earth and Planetary Sciences ETDs
Understanding the natural petrologic and tectonic processes, such as slab subduction, requires accurate determination of the pressure (P) and temperature (T) conditions of these processes. Recent development of elastic thermobarometry based on the difference between the elastic evolution of mineral inclusions and their host minerals allows constraining the formation P-T conditions of the inclusion/host system without assuming thermodynamic equilibrium, which is typically needed for the widely used chemistry-based thermobarometry in metamorphic petrology. However, the reliability of elastic thermobarometry heavily depends on the accurate determination of the high P-T single-crystal elastic properties of relevant minerals. In this study, we performed the …
Testing The Niche Center Hypothesis In The Fossil Record Of Atlantic Bivalves, Rhiannon Z. Nolan
Testing The Niche Center Hypothesis In The Fossil Record Of Atlantic Bivalves, Rhiannon Z. Nolan
Earth and Planetary Sciences ETDs
Paleoecological analyses of six shallow marine bivalves were conducted to test the Abundant Center Hypothesis using data from the fossil record of the Pleistocene through modern day. This hypothesis predicts the highest abundance of a species is at the center of the geographic or environmental range, decreasing toward the edges. In geographic space, distances to a centerline within a geographic range were variably correlated with population abundances, and some species displayed a sharp drop-off in abundance as distance increased. In environmental space, bivalve species showed moderate correlations between abundance and centrality when measured using cumulative data across the last 2.8 …
Seismic Shadow Zone Investigation In The Upper Magma Reservoir Of The Yellowstone Caldera, Sarah Nolt-Caraway
Seismic Shadow Zone Investigation In The Upper Magma Reservoir Of The Yellowstone Caldera, Sarah Nolt-Caraway
Earth and Planetary Sciences ETDs
This study investigates whether the Yellowstone Caldera has enough melt to mute S-waves, creating a seismic shadow zone. Using a dense nodal deployment of ~650 stations, 7-9 earthquakes during the nodal deployment, and 21 broadband stations with 3,000-4,000 events per station; amplitude and noise maps, seismograms, and automatic phase picks probabilities from a deep learning model were analyzed to assess the potential role of melt, crustal attenuation, and noise in affecting body waves, particularly S-phases. The results are inconclusive, with unclear evidence whether observed amplitude decay is normal signal decay due to distance, noise-related, melt, or from scattering and intrinsic …
Weathering, Erosion, And Dust Accumulation At Stoneman Lake, Arizona, Usa: Timescales And Drivers Of Geomorphic Activity Across The Southwest, Spencer Staley, Peter J. Fawcett, R. Scott Anderson, Gonzalo Jiménez-Moreno, Vera Markgraf, Erik T. Brown, Matthew E. Kirby
Weathering, Erosion, And Dust Accumulation At Stoneman Lake, Arizona, Usa: Timescales And Drivers Of Geomorphic Activity Across The Southwest, Spencer Staley, Peter J. Fawcett, R. Scott Anderson, Gonzalo Jiménez-Moreno, Vera Markgraf, Erik T. Brown, Matthew E. Kirby
Earth and Planetary Sciences ETDs
Lengthy and well-dated terrestrial records of the Quaternary Period with the appropriate proxies show how the critical zone responds to environmental change. In southwestern North America, resolving the many effects of aridity through time provides crucial context for addressing contemporary climate issues. However, arid conditions are generally non-conducive to paleo-record preservation, causing knowledge gaps during relevant climatic episodes. An ~80 m-long sediment core (STL14) from Stoneman Lake contains a continuous archive of conditions from local to regional scale since the early Pleistocene (~1.3 Ma) and is, therefore, a unique and immensely valuable scientific resource. STL is situated in a montane …
Per- And Polyfluoroalkyl Substances (Pfas) In Treated Sewage Sludge From Michigan Wastewater Treatment Plants, Garrett Wesley Link
Per- And Polyfluoroalkyl Substances (Pfas) In Treated Sewage Sludge From Michigan Wastewater Treatment Plants, Garrett Wesley Link
Masters Theses
Concentrations, compositions, and variability of Per- and Polyfluoroalkyl Substances (PFAS) in sewage sludge are characterized using an extensive dataset of 350 samples from 190 wastewater treatment plants (WWTPs) across Michigan. All samples are comprised of final treated sewage sludge generated at the end of the wastewater treatment process. Concentrations of Σ24 PFAS are log normally distributed with a range of 1 to 3200 ng/g dry wt. and of average 108 ± 277 ng/g dry wt. Compounds with carboxyl and sulfonic functional groups comprised 29% and 71% of Σ24 PFAS concentrations, respectively, on average. Primary sample variability is associated …
Water Quality Land Cover Change And Water Quality In Wetlands At The City Of Gresham, Or, Evelyn Barajas, Michael Gonzalez
Water Quality Land Cover Change And Water Quality In Wetlands At The City Of Gresham, Or, Evelyn Barajas, Michael Gonzalez
altREU Projects
The City of Gresham, Oregon has implemented constructed wetlands around the area as an attempt to collect, filter, and purify water from different sources such as rain, agricultural waste, and domestic waste. We focused our research on three different facilities: Columbia Slough Water Quality Facility (CSWQF), Fairview Creek Water Quality Facility, and Brookside Water Quality Facility. For each of these, we conducted tests and looked at the concentration levels for nitrogen and phosphorus nutrients such as NH3-N (ammonium), NO3-N (nitrate), TKN (total Kjeldahl nitrogen), O-PO4 (phosphate), and Total P (total phosphorus), as well as heavy metals like Total Cu (total …
Short-Term Response In Soil Health To Management Practices Within Large- And Small-Scale Cropping Systems In Arkansas, Torri Holder
Short-Term Response In Soil Health To Management Practices Within Large- And Small-Scale Cropping Systems In Arkansas, Torri Holder
Graduate Theses and Dissertations
Improving soil health is a growing area of interest within large- and small-scale agricultural systems in Arkansas as producers face increasing input costs, increased awareness of variability and intensity in extreme weather events, decreasing resource availability, and suboptimal productivity related to environmental degradation. Practices aimed at improving soil health such as cover cropping and the use of organic amendments are increasingly recommended and adopted; however, research on optimal management in the Mid-South is lacking. Two studies were conducted to evaluate the effectiveness of soil health management under both small- and large-scale farming operations in Arkansas. The objective of the small-scale …
Nutrient Responses To Hippuric Acid In Sheep Urine Applied To Pasture Soil Cores, Ethan Avery Collins
Nutrient Responses To Hippuric Acid In Sheep Urine Applied To Pasture Soil Cores, Ethan Avery Collins
Graduate Theses and Dissertations
Hippuric acid is a breakdown product of tannins, which bind with proteins in the animal rumen and slow down protein metabolism, thus increasing nitrogen (N) retention in the animal. Increased hippuric acid concentration in bovine and ovine urine applied to soil may decrease rates of nitrification, denitrification, and nitrous oxide fluxes in pasture soils. Additionally, condensed tannins have increased rates of carbon mineralization when incorporated in humus and leaf litter. To evaluate effects of hippuric acid concentration, treatments of urine from sheep fed a tannin-supplemented diet, synthetic urine, or urea controls were applied to intact soil cores seeded with crabgrass …
Runoff Water Quality And Crop Growth As Affected By Wastewater-Derived Struvite, Machaela Morrison
Runoff Water Quality And Crop Growth As Affected By Wastewater-Derived Struvite, Machaela Morrison
Graduate Theses and Dissertations
Mined phosphate rock, used to produce phosphorus (P) fertilizers, is a finite resource. Struvite (MgNH4PO4 • 6H2O) that has been synthetically produced from a stock solution of known P and nitrogen (N) concentrations has been shown to be an effective, alternative fertilizer-P source for various crops. However, little is known about the runoff-water-quality implications from and the crop response to soil application of struvite created from an actual municipal wastewater source. This study consisted of two objectives: i) to evaluate the effects of soil [i.e., Creldon (Oxyaquic Fragiudalf), Dapue (Fluventic Hapludoll), Roxana (Typic Udifluvent), and Calloway (Aquic Fraglossudalf) series], fertilizer-P …
Understanding The Factors Affecting Nebraskan Farmers’ And Landowners' Decision To Adopt Precision Agricultural Technologies And Programs, Corrin C. Winter
Understanding The Factors Affecting Nebraskan Farmers’ And Landowners' Decision To Adopt Precision Agricultural Technologies And Programs, Corrin C. Winter
School of Natural Resources: Dissertations, Theses, and Student Research
Advisors: Andrew Little, Christopher Chizinski
To gain insights into the challenges faced by Nebraska farmers and landowners when adopting precision agriculture technologies, I analyzed data collected from a 2022 survey involving 7,503 participants, consisting of producers and farmland owners from across the state of Nebraska. The primary objective was to provide valuable insights for agencies seeking to improve their precision agriculture and conservation outreach efforts for the benefit of conservation and Nebraskan farmers and landowners. This study aimed to understand key factors influencing adoption behaviors by evaluating the constraints to precision agriculture adoption, assessing the impact of producer and landowner …
Evaluating The Feasibility Of Using Strain Measured During Sinusoidal Rate Pumping Tests To Characterize An Aquifer, Riley Blais
Evaluating The Feasibility Of Using Strain Measured During Sinusoidal Rate Pumping Tests To Characterize An Aquifer, Riley Blais
All Theses
Pumping tests with sinusoidal variation in pumping rate have been proposed as a method for improving aquifer characterization. These tests can interrogate a larger aquifer volume than slug tests and they can be more sensitive to small variations in drawdown. Current methods of using sinusoidal variations of rate are based on measuring pressure signals from the reservoir or aquifer, which requires access to monitoring wells. An alternative approach has been developed that measures the strain in the vadose zone instead of pressure in the reservoir. An instrument has been developed at Clemson University that can measure small strains using optical …
Influence Of Urbanization And Climate On Irrigation Diversions And Return Flows In The Lower Boise River Basin, Bridget Bittmann
Influence Of Urbanization And Climate On Irrigation Diversions And Return Flows In The Lower Boise River Basin, Bridget Bittmann
Boise State University Theses and Dissertations
The western US is facing both the rapid urbanization of agricultural lands and a changing climate, producing subsequent changes to irrigation water demand and availability. Adaptive water management requires knowledge regarding how and why water usage and availability is changing; however, managers often do not possess the tools or resources for the necessary analysis. These environmental changes are also place-based, meaning that water managers cannot directly use studies from other basins to actively manage theirs. Co-produced, actionable research can help fill this knowledge gap and provide the necessary information for adaptive management. The Lower Boise River Basin (LBRB) in southwestern …
Effects Of Discharge And Morphology On Fluvial Sound, Scott J. Gauvain
Effects Of Discharge And Morphology On Fluvial Sound, Scott J. Gauvain
Boise State University Theses and Dissertations
Rivers, streams, and tributaries play a critical role in the global water cycle and their dispersion of freshwater is essential for widespread human consumption, crop irrigation, waste management, and hydropower generation. Currently, there is a need for innovative, non-invasive, and low-cost methods of surface freshwater discharge gauging. With careful site selection, recording the acoustics produced by streamflow could be used reliably and inexpensively to infer changes in local discharge. An important knowledge gap currently preventing the use of acoustics for stream gauging is the unknown relationships by which stream sounds depend on discharge and stream morphology. To address this, I …
Picking Up Steam: A Year Long Infrasonic Record Of Steamboat Geyser. Minor And Major Paroxysms Of The Multi-Phase Eruptions At Steamboat Geyser, Yellowstone National Park, Margaret Holahan
Boise State University Theses and Dissertations
The renewed activity of the world’s tallest geyser, Steamboat Geyser (Yellowstone National Park) in 2018, offers the opportunity to utilize long-term continuous infrasound and low-frequency acoustic monitoring to quantify eruptive behaviors. Eruption parameters including onset timing, duration, phase transitions between steam and water, instantaneous sound intensity, eruptive power, energy content, and spectral character, may be used to characterize individual eruption styles and reveal eruption trends. I interpret the character of the acoustic radiation through corroboration of first-hand observations and time-lapse video. I find that infrasound (acoustic energy below 20 Hz) is a particularly effective tool for tracking the evolving eruption …
Characteristics Of Stream Source Water Contributions And Associated Geochemical Signatures Along A Climate And Vegetation Gradient In A Glacierized Landscape, Southcentral Alaska, Hannah K. Richardson
Characteristics Of Stream Source Water Contributions And Associated Geochemical Signatures Along A Climate And Vegetation Gradient In A Glacierized Landscape, Southcentral Alaska, Hannah K. Richardson
Boise State University Theses and Dissertations
Mountain-derived snow and ice melt are essential for global water resources, and over one-sixth of the population depends on melt for freshwater. Rising air temperatures are causing vegetation to replace snow- and ice-covered landscapes and precipitation regimes to change. Collectively, these changes will alter the hydrology of mountain environments, although the exact impacts to hydrologic regimes are poorly understood. The source waters of streamflow (i.e. the proportion of ice melt, snowmelt, rain, and groundwater) dictate the timing and magnitude and affect temperature, sediment, and nutrient fluxes. By examining differences in source waters across basins with varying land covers and precipitation …
Climatic Influences On Incipient Alteration In Mars-Relevant Ultramafic Soils, Anthony Feldman
Climatic Influences On Incipient Alteration In Mars-Relevant Ultramafic Soils, Anthony Feldman
UNLV Theses, Dissertations, Professional Papers, and Capstones
An ongoing debate exists around the nature of the climatic conditions present during the Noachian and early Hesperian periods (~4.1 to 3 Gyr ago) of Mars’ ancient history. The various theories put forward can reasonably be grouped into “warm and wet” vs “cold and icy” camps. Warm and wet approximates an Earth-like system with a relatively clement climate with significant liquid water present including potentially long-lived oceans. Cold and icy theories generally postulate thick ice sheets at high elevations with periodic warming events driving precipitation and the formation of river channels and leading to the formation of chemical alteration products. …
Magmatic Processes Leading To Compositional Diversity In The Mars Crust, Amanda Marie Ostwald
Magmatic Processes Leading To Compositional Diversity In The Mars Crust, Amanda Marie Ostwald
UNLV Theses, Dissertations, Professional Papers, and Capstones
The ancient Mars crust can yield insights into planet formation and evolution that Earth cannot. Direct investigation of the martian surface is limited to studies on meteorites and rover-obtained analyses. The nakhlites and chassignites, two classes of martian meteorites, are together the largest suite of martian meteorites derived from a single location on the surface. As such, they present a rare opportunity to study the Mars crust in detail using samples bearing a contextual relationship. Rover studies have found a surprising amount of compositional diversity in surface materials, the formation mechanisms of which are not well-constrained. This dissertation leverages meteorites …
Origin Of The Mega-Streamlined Morphology In Ne Africa And Arabia: Remote Sensing And Field-Based Investigations, Mohamed Samy Mohamed Elhebery
Origin Of The Mega-Streamlined Morphology In Ne Africa And Arabia: Remote Sensing And Field-Based Investigations, Mohamed Samy Mohamed Elhebery
Dissertations
Mega-streamlined landforms on Earth and Mars have been attributed to aeolian, glaciogenic, fluvial, and tectonic processes. Identifying the forces that shaped these landforms is paramount for understanding landscape evolution and constraining paleo-climate models and ice sheet reconstructions. Exhumed Late Ordovician glacial deposits and landscape of the North Gondwana are reported here for the first time from SE Egypt. Using field and remote sensing (Advanced Land Observing Satellite [ALOS], Phased Array L-band Synthetic Aperture Radar (PALSAR) radar, multispectral Landsat TM datasets, and digital elevation models (DEMs) I mapped the distribution of the Late Ordovician glacial features (i.e. deposits and landforms) in …
Englacial Drainage Drives Positive Feedback Depression Growth On The Debris-Covered Ngozumpa Glacier, Nepal, R. M. Strickland, M. D. Covington, J. D. Gulley, R. B. Kayastha, J. M. Blackstock
Englacial Drainage Drives Positive Feedback Depression Growth On The Debris-Covered Ngozumpa Glacier, Nepal, R. M. Strickland, M. D. Covington, J. D. Gulley, R. B. Kayastha, J. M. Blackstock
Geosciences Faculty Publications and Presentations
The development of hummocky topography is a poorly understood aspect of down-wasting on debris-covered glaciers that is often attributed to variable debris thickness. Thousands of enclosed depressions pit the hummocky topography. To better understand depression growth, we examined the size distribution and geometry of depressions on the Ngozumpa Glacier, in the Everest Region of Nepal. The depressions exhibited a power-law size distribution, fractal perimeters, and power-law depth-area scaling, which suggest positive feedback growth. With a simple model, we showed that positive feedback growth produces similar power-law size distributions. Based on these findings, we propose a “sinkhole” hypothesis for the development …
Phase Distribution Of Nickel, Chromium, And Cobalt In Seawater At Olivine-Enriched Beaches: Implications For Carbon Capture By Enhanced Silicate Weathering, Nathaniel J. Padrnos
Phase Distribution Of Nickel, Chromium, And Cobalt In Seawater At Olivine-Enriched Beaches: Implications For Carbon Capture By Enhanced Silicate Weathering, Nathaniel J. Padrnos
Master's Theses
The application of olivine to coastal areas is a proposed method of removing carbon dioxide from the atmosphere for climate change mitigation. Olivine is abundant and dissolves relatively fast, but it contains trace amounts of nickel (Ni), chromium (Cr), and cobalt (Co) which may be toxic to marine biota in cases of widespread coastal olivine spreading. Prior studies have suggested that Ni concentrations in marine sediments and/or the overlying water column due to olivine dissolution could be a limiting factor for its carbon capture potential. Therefore, it is critical to understand and model the processes affecting trace metal bioavailability after …
Late Jurassic Paleogeography Of The U.S. Cordillera From Detrital Zircon Age And Hafnium Analysis Of The Galice Formation, Klamath Mountains, Oregon And California, Usa, Kathleen D. Surpless, Ryan Wayne Alford, C. Barnes, A. Yoshinobu, Natalee E. Weis
Late Jurassic Paleogeography Of The U.S. Cordillera From Detrital Zircon Age And Hafnium Analysis Of The Galice Formation, Klamath Mountains, Oregon And California, Usa, Kathleen D. Surpless, Ryan Wayne Alford, C. Barnes, A. Yoshinobu, Natalee E. Weis
Earth and Environmental Geosciences Faculty Research
The Upper Jurassic Galice Formation, a metasedimentary unit in the Western Klamath Mountains, formed within an intra-arc basin prior to and during the Nevadan orogeny. New detrital zircon U-Pb age analyses (N = 11; n = 2792) yield maximum depositional ages (MDA) ranging from ca. 160 Ma to 151 Ma, which span Oxfordian to Kimmeridgian time and overlap Nevadan contractional deformation that began by ca. 157 Ma. Zircon ages indicate a significant North American continental provenance component that is consistent with tectonic models placing the Western Klamath terrane on the continental margin in Late Jurassic time. Hf isotopic analysis of …
New Species Of Dryolestoid From The Late Cretaceous Allen Formation And Implications For South American Faunal Diversity., Brigid Erin Connelly
New Species Of Dryolestoid From The Late Cretaceous Allen Formation And Implications For South American Faunal Diversity., Brigid Erin Connelly
Electronic Theses and Dissertations
Dryolestoids are extinct cladotherians mammals from the Jurassic and Cretaceous periods. I describe a collection of dryolestoid specimens from the Late Cretaceous localities of Cerro Tortuga (Allen Formation), Anfiteatro 1, and Shining (both La Colonia Formation) from Patagonia, Argentina. Using comparative morphology, I identify a new species of meridiolestidan dryolestoid based on eleven specimens across both formations. The new species’ recovery from La Colonia Formation represents the first dryolestoid connection between the two approximately contemporaneous formations. The species’ morphology may represent an ecological shift within Meridiolestida from insectivory to herbivory, showing a transition in characters between the plesiomorphic sharp-toothed meridiolestidans …
Effects Of Short-Term Exposure To A Pesticide Mixture On Free-Swimming Behavior In Goldfish, Carassius Auratus, Esmirna Cantu, Michelle Rivera, Brittney Lacy, Md. Saydur Rahman
Effects Of Short-Term Exposure To A Pesticide Mixture On Free-Swimming Behavior In Goldfish, Carassius Auratus, Esmirna Cantu, Michelle Rivera, Brittney Lacy, Md. Saydur Rahman
School of Earth, Environmental, & Marine Sciences Faculty Publications
Highlights
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We observed effects of pesticides exposure on free-swimming behaviors in goldfish.
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Pesticides profoundly impacting natural swimming patterns.
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Behavioral analysis showed a dose- and time-dependent, decrease in distance swam.
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Vertical/horizontal spatial behavioral use both affected under exposure conditions.
Abstract
The prevalence of pesticides in the aquatic environment continues to increase due to anthropogenic activities and poses a threat to aquatic organisms. Notably, the intensive use of pesticides can cause detrimental effects (i.e., chemical stressors) on animal behavior. The aim of this study was to determine the short-term exposure effects (5-day) of an environmentally relevant pesticide mixture (low- and high-dose: metolachlor …