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Metal Zonation And Evolution Of The Bronson Slope Porphyry Cu-Au-Mo Deposit In The Iskut Region Of British Columbia, Canada, Luis Jacobo Yagual Dec 2025

Metal Zonation And Evolution Of The Bronson Slope Porphyry Cu-Au-Mo Deposit In The Iskut Region Of British Columbia, Canada, Luis Jacobo Yagual

Open Access Theses & Dissertations

Bronson Slope is a Cu-Au-Mo porphyry deposit located within the Stikine Terrane in the Golden Triangle District of northwestern British Columbia, Canada. This deposit represents a complex, multistage magmatic-hydrothermal system emplaced into sedimentary and volcanoclastic rocks of the Triassic Stuhini Group. Bronson has an inferred resource of 517.3 Mt at 0.33 g/t Au, and 0.09% Cu. This study integrates detailed and quick logging from 20 drill holes, totaling 20,296m, SWIR spectral analysis, ICP-MS geochemistry, XRF analysis, magnetic susceptibility measurements, geochronology, and 3D models developed in Leapfrog Geo which define the stratigraphy, intrusive geometry, extension, alteration footprint assemblage, metal zonation, and …


Examination Of Differences Of Similar-Sized Martian Craters At The Simple-Complex Transition As Revealed By High-Resolution Imaging And Stereo-Derived Topography, Lindsey Dorn Dec 2025

Examination Of Differences Of Similar-Sized Martian Craters At The Simple-Complex Transition As Revealed By High-Resolution Imaging And Stereo-Derived Topography, Lindsey Dorn

Geosciences

Impact craters on Mars have a wide range of morphologies, and the relationship between the mechanics of their formation and their eventual morphologies is still not completely understood. By examining craters within a narrow diameter range, impact energies are constrained to similar values - enabling focused investigation of target properties and their influence on crater excavation and modification. There is a transition from simple bowl-shaped depressions to complex craters with terraced walls and central floor structures with increasing crater diameter. We analyzed target influences on morphology by examining eleven well-preserved craters of varying morphologies in the 7 to 9 km …


Evaluating Utilidor Performance And Ground Temperature Variability In UtqiaġVik, Tate Rachow Dec 2025

Evaluating Utilidor Performance And Ground Temperature Variability In UtqiaġVik, Tate Rachow

Geosciences

Permafrost degradation in Arctic regions poses increasing risks to infrastructure as climate warming accelerates thaw processes, alters hydrology, and deepens the active layer. In Utqiaġvik, Alaska, utilidors— utility conduits—play a vital role in protecting water and wastewater services, yet their thermal performance under changing conditions remains poorly constrained. This thesis evaluates the thermal behavior of the Site U-1 direct buried pipes on Stevenson Street using historical thermistor resistance data converted to temperature, combined with calibrated two- dimensional TEMP/W numerical models. The models incorporate layered backfill materials and polyurethane insulation, while also simulating operational influences of water and wastewater temperatures. Calibration …


Navigating Seismic Anisotropy, With Applications To Alaska, Aakash Gupta Dec 2025

Navigating Seismic Anisotropy, With Applications To Alaska, Aakash Gupta

Geosciences

Seismic anisotropy characterizes how elastic waves travel through solid materials with different speeds, depending on the direction of the waves and the direction of particle motion of the waves. Evidence of seismic anisotropy in the Earth is widespread, from seismic waves sampling the crust, mantle and even the core, to active-source, industry-scale seismic experiments, to laboratory mea­ surements of rock samples from boreholes or at the surface. Global models of the Earth provide a highly averaged image of anisotropy. Studies based on shear wave splitting measurements from local and global earthquakes indicate that the anisotropy in the Earth is much …


Earthquake Relocation, Fault Complexity, And Nucleation Patterns In Interior Alaska, Nealey Sims Dec 2025

Earthquake Relocation, Fault Complexity, And Nucleation Patterns In Interior Alaska, Nealey Sims

Geosciences

Interior Alaska is one of the most seismically active intraplate regions in North America, yet its faults remain poorly defined due to diffuse seismicity and limited surface expression. Bounded by the Denali and Tintina fault systems, the region hosts the Minto Flats, Fairbanks, and Salcha fault zones, which produce large earthquakes, as evidenced from the 1937 Ms 7.3 Salcha and 1995 Mw 6.0 Minto Flats events. Despite their hazard potential, these structures have historically been represented as broad seismic zones rather than mapped faults. This dissertation applies mod­ern seismological approaches—network matched filtering, waveform cross-correlation, and rela­tive relocation—to build high-resolution earthquake …


Characterizing Magmatic Processes At Pavlof And Augustine Volcanoes, Alaska, Through Changes In Volatile, Melt, And Phenocryst Geochemistry, Valerie Wasser Dec 2025

Characterizing Magmatic Processes At Pavlof And Augustine Volcanoes, Alaska, Through Changes In Volatile, Melt, And Phenocryst Geochemistry, Valerie Wasser

Geosciences

Alaska is home to 54 historically active volcanoes with eruptions posing not only hazards to life and property but also endangering air traffic and affecting the economy. Volcanic processes are complex, and their investigation requires the application of multidisciplinary tools and perspectives from both geophysics and geology. Petrology and geochemistry are the study of the chemical and mineralogical make up of rocks and can provide insights into mantle, crustal and shallow near-surface magmatic processes for recent and prehistoric eruptions. Here I investigate magmatic processes by examining mineral compositional changes across dissolution surfaces in crystal clots at Augustine Volcano, and changes …


Climate Change Has Increased Global Evaporative Demand Except In South Asia, Saeed Karimzadeh, Arman Ahmadi, Dennis Baldocchi, Joshua B. Fisher Nov 2025

Climate Change Has Increased Global Evaporative Demand Except In South Asia, Saeed Karimzadeh, Arman Ahmadi, Dennis Baldocchi, Joshua B. Fisher

Biology, Chemistry, and Environmental Sciences Faculty Articles and Research

Climate change alters how strongly the atmosphere draws water from the land, yet a consistent global assessment of this evaporative demand has been lacking. Here, we analyze 45 years of climate data and global models to quantify trends in the key drivers—air temperature, humidity, radiation, wind speed, and cloud cover—that determine the atmosphere’s drying power. We find that evaporative demand has increased worldwide, indicating a stronger atmospheric thirst, except in South Asia, where it has declined. There, widespread irrigation has increased soil and air moisture, enhanced cloud formation, and reduced sunlight reaching the surface, counteracting the global signal. These contrasting …


High Variability In Flood Discharge And Stage Accelerates River Mobility, Chenliang Wu, Wonsuck Kim, Shuo Yang, Frank Tsai, Jeffrey A. Nittrouer, Tian Y. Dong, Duhwan Keum, Kyle M. Straub Nov 2025

High Variability In Flood Discharge And Stage Accelerates River Mobility, Chenliang Wu, Wonsuck Kim, Shuo Yang, Frank Tsai, Jeffrey A. Nittrouer, Tian Y. Dong, Duhwan Keum, Kyle M. Straub

School of Earth, Environmental, & Marine Sciences Faculty Publications

Lateral channel migration is a fundamental process in natural alluvial rivers; however, the factors that control the rate of migration remain unclear. Despite its importance in shaping river morphology, the impact of water discharge on river mobility is still largely unexplored. Here, we leverage a dataset of 64 rivers across the globe to show that higher variability in river discharge and stage promotes higher rates of river migration. To reveal the physical processes behind this relationship, we focused analyses on the lowermost 500 kilometers of the Mississippi River, where a pronounced gradient in water stage variability and migration rate exists. …


Phase Equilibria Modeling Constraints On Channel Flow Of Metasedimentary Crust Beneath The Southeastern Tibetan Plateau, Govind Joshi, Gregory Dumond Nov 2025

Phase Equilibria Modeling Constraints On Channel Flow Of Metasedimentary Crust Beneath The Southeastern Tibetan Plateau, Govind Joshi, Gregory Dumond

Geosciences Faculty Publications and Presentations

Lower crust of the southeastern Tibetan Plateau includes 100 s of km2-scale zones of low resistivity at 20-40 km-depths indicating the presence of melt +/- fluid +/- graphite. These zones coincide with interconnected zones of low shear wave velocity. Data from central and southeastern Tibet support the occurrence of meta-sedimentary felsic granulites in the lower crust along a backarc-like geothermal gradient. Phase equilibria modeling of average metasedimentary pelite and greywacke bulk compositions constrained by these geophysical data explored the impact of partial melting on shear wave velocity for a range of fluid content. Low shear wave velocities beneath southeastern Tibet …


An Objective Method To Locate Shear Lines During The Northeast Monsoon Season In The Philippines, Lyndon Mark P. Olaguera, John A. Manalo, Jun Matsumoto, Faye Abigail T. Cruz, Jose Ramon T. Villarin Nov 2025

An Objective Method To Locate Shear Lines During The Northeast Monsoon Season In The Philippines, Lyndon Mark P. Olaguera, John A. Manalo, Jun Matsumoto, Faye Abigail T. Cruz, Jose Ramon T. Villarin

SOSE Affiliate: Manila Observatory

The shear line is a narrow zone of maximum horizontal wind shear, typically identified as a confluence zone of low-level wind streams. Previous studies showed that this system can trigger heavy to extreme rainfall events in the Philippines during the northeast monsoon season. However, a research gap remains in objectively identifying and locating this system. Thus, this study develops a detection method that may be used for monitoring and forecasting the location of shear lines. Results show that the gradient of meridional winds in the y-direction (∂V925hPa/∂y), the boundary layer moisture flux convergence, and the 925 hPa relative vorticity may …


Controls On Speleothem Carbon Isotopes, Paloma Marcos Nov 2025

Controls On Speleothem Carbon Isotopes, Paloma Marcos

Undergraduate Research Symposium Posters

The Sistema Huautla cave system is the deepest known in the Western Hemisphere. It is located in the Sierra Mazateca Mountain Ranges near Jiménez de Huautla, Oaxaca. There are over 29 separately discovered entrances into this karst environment making it the 28th longest cave system in the world. It can be considered by some as one of the most complex vertical drainage systems on Earth. This extensive study site has been an area of interest among cavers and scientific researchers for nearly 6 decades. Speleothem samples from the study sites have been found to be over 433,000 years old. The …


The Relationship Between Lineaments And Cave Passages In Unfaulted Gently-Folded Strata, Snail Shell Cave, Central Tennessee, Usa, Mark Abolins, Joseph Firkaly-Paciera, Blake King, Cris Ocasio-Valentin, Jackson Slighter, Teagan Sullivan, Justin Whited Nov 2025

The Relationship Between Lineaments And Cave Passages In Unfaulted Gently-Folded Strata, Snail Shell Cave, Central Tennessee, Usa, Mark Abolins, Joseph Firkaly-Paciera, Blake King, Cris Ocasio-Valentin, Jackson Slighter, Teagan Sullivan, Justin Whited

International Journal of Speleology

Near Snail Shell Cave in central Tennessee, USA, seven image interpreters independently mapped lineaments using a 3DEP LiDAR DTM, revealing geomorphic and structural differences in and near different parts of the cave. MANOVA comparison of lineament and cave passage trend for Western, Central, and Eastern Snail Shell caves reveals statistically significant differences (p <0.05). The Western cave (mean depth 44 m) is in the gently-dipping limb of the Snail Shell anticline, and the Central cave (mean depth 31 m) is in the anticline hinge. In contrast, many Eastern cave passages (mean depth 40 m) cut across the anticline hinge and part of the limb of the Overall syncline. For both the Western and Central caves, a post-hoc Tukey’s HSD test fails to show that lineament trend within 235 m of the cave differs significantly from passage trend, and the test fails to show that the two differ significantly within 235 and 433 m of the Eastern cave. Additional statistical testing fails to show a difference between Western passage trend and bed strike, indicating the likelihood that lineaments and passages developed within strike-joints. However, testing shows a statistically significant difference between passage trend and bed strike for the Central and Eastern caves. The strike of joints inside the Eastern cave shows that it is within a joint zone which penetrates to depths of at least 80 m and is expressed at the surface as an ~4.2 km-long belt of elevated lineament line density. The lack of a statistically significant difference between Eastern passage trend and the trend of a nearby topographic escarpment suggests that many joints are stress release fractures formed during relatively recent erosion. For the Eastern cave, intersections between lineaments and structures would be attractive targets for groundwater exploration at depths typical of wells in carbonates.


Characterization Of River Discharge And Interaction With Shallow Groundwater Aquifers Along The Wabash River Using Seismological Methods, Jessica M. Cyr, Xiaotao Yang, Marty D. Frisbee Nov 2025

Characterization Of River Discharge And Interaction With Shallow Groundwater Aquifers Along The Wabash River Using Seismological Methods, Jessica M. Cyr, Xiaotao Yang, Marty D. Frisbee

Discovery Undergraduate Interdisciplinary Research Internship

The interaction between shallow aquifers and local rivers in the West Lafayette, Indiana area remains poorly understood. While surface water levels in the Wabash River and its tributaries are monitored at several USGS stream gauges, groundwater fluctuations are less well documented. Methods using seismic recordings, sensitive to subtle ground vibrations and subsurface structure, provide an alternative to characterize groundwater levels and river discharge. This project analyzes the temporal variations of ambient noise seismic data, examining the relationship to USGS river discharge, precipitation records, and other environmental factors. We currently focus on 1) changes in maximum amplitudes and peak frequencies within …


A Bioarchaeological Study Of The Individuals From The Városfalva Burial Mound In Transylvania, Romania (15th-19th Century), Vanessa C. Reeves Nov 2025

A Bioarchaeological Study Of The Individuals From The Városfalva Burial Mound In Transylvania, Romania (15th-19th Century), Vanessa C. Reeves

USF Tampa Graduate Theses and Dissertations

This study explores the lives and deaths of the Szekler people recovered from a burial mound in the Transylvanian village of Városfalva. The Transylvanian plateau is located in present day Romania, and is protected on the east and the south by the Carpathian Mountains. The Szekler people arrived in this area around 1000 CE, and were a nomadic group originating in the Asian Steppes region who later intermarried with various migratory groups as they moved across the Eurasian plains. The Szeklers eventually banded together with the proto-Hungarian Magyar peoples and settled in the Carpathian Basin, the easternmost frontier of the …


Formation And Extent Of The Cretaceous West Mountains Plutonic Complex, Ellen M. Nelson, Claire E. Ruggles, Basil Tikoff, Mollie Patzke, Kathleen D. Surpless, Jeffrey Vervoort, Richard Gaschnig Nov 2025

Formation And Extent Of The Cretaceous West Mountains Plutonic Complex, Ellen M. Nelson, Claire E. Ruggles, Basil Tikoff, Mollie Patzke, Kathleen D. Surpless, Jeffrey Vervoort, Richard Gaschnig

Earth and Environmental Geosciences Faculty Research

The West Mountains plutonic complex is a series of intrusive bodies, presently located in Idaho, that formed during a continuous period of Early to mid-Cretaceous magmatism in the northwest North American Cordillera. Granitoids of the West Mountains plutonic complex were emplaced across the boundary between accreted terranes and Laurentia following the Jurassic accretion of the Blue Mountains Province. New U-Pb zircon crystallization dates from the West Mountains plutonic complex ranging from 130 to 109 Ma and new zircon εHf isotopic compositions ranging from +12.1 to +4.7 suggest the complex is older and compositionally distinct from the younger than 85 Ma …


Record Of The Late Jurassic Cordilleran Margin From Detrital Zircon Analysis Of The Galice And Mariposa Formations, California And Oregon, Kathleen D. Surpless, Calvin Barnes, Aaron Yoshinobu Nov 2025

Record Of The Late Jurassic Cordilleran Margin From Detrital Zircon Analysis Of The Galice And Mariposa Formations, California And Oregon, Kathleen D. Surpless, Calvin Barnes, Aaron Yoshinobu

Earth and Environmental Geosciences Faculty Research

Details of the Late Jurassic tectonic evolution of the North American continental margin remain controversial, but a clear understanding of Late Jurassic tectonics is essential for understanding subsequent terrane accretion and displacement. Upper Jurassic strata of the Galice Formation in the western Klamath Mountains province and the Mariposa Formation in the Western Sierra Nevada metamorphic province were deposited along the margin of North America during this critical time. The Galice and Mariposa Formations have long been correlated, and these strata are the youngest rocks deformed during Late Jurassic Nevadan deformation in Oregon and California. Published and new detrital zircon age …


Magnesium, Iron, And Calcium Isotope Signatures Of Chicxulub Impact Spherules: Isotopic Fingerprint Of The Projectile And Plume Thermodynamics, Courtney Jean Rundhaug, Martin Schiller, Martin Bizzarro, Zhengbin Deng, Hermann D. Bermúdez Nov 2025

Magnesium, Iron, And Calcium Isotope Signatures Of Chicxulub Impact Spherules: Isotopic Fingerprint Of The Projectile And Plume Thermodynamics, Courtney Jean Rundhaug, Martin Schiller, Martin Bizzarro, Zhengbin Deng, Hermann D. Bermúdez

Department of Earth and Environmental Studies Faculty Scholarship and Creative Works

The Cretaceous-Paleogene boundary (KPB) represents a massive extinction event in Earth's history, probably triggered by the Chicxulub asteroid impact ∼66 Ma. The event dispersed vast volumes of ejecta materials including exceptionally preserved impact spherules in the Gorgonilla Island KPB section. Previous work identified three populations of spherules at Gorgonilla: 1) ballistically transported molten spherules, 2) a mixture of molten and condensed spherules dispersed by the expansion of a high-temperature, turbulent cloud (the "pyrocloud"), and 3) tiny droplets condensed from the plume (the "fireball layer"). We determine the Mg, Fe, and Ca isotopic compositions of pristine spherules to better understand the …


Playa Sediment Bioaccessibility Presents Previously Unknown Risks To Population Health In A Water-Stressed Region Undergoing Lake Desiccation: Salton Sea, Usa, Jordan Jaeger Nov 2025

Playa Sediment Bioaccessibility Presents Previously Unknown Risks To Population Health In A Water-Stressed Region Undergoing Lake Desiccation: Salton Sea, Usa, Jordan Jaeger

Theses

Globally, drylands are expanding, and endorheic basins are in rapid decline. Saline lake desiccation exposes lakebed playa likely to become dust, posing potential health risks to surrounding communities. Studies investigating health risks from playa dust exposure often focus on health effects associated with the presence of airborne particulates, but fewer studies investigate health risks associated with dust source chemistry. This study examines dust source particle composition in a desiccating inland sea in a water-stressed agricultural region of California. Specifically, chemical bioaccessibility of bound trace elements uncovers risks to children, adults, and agricultural worker health. Arsenic exposure via sediment ingestion poses …


Source Apportionment And Potential Health Risks Of Trace Metals In A Contaminated Urban River In New York/New Jersey Harbor System, Md Shahnul Islam, Sana Mirza, Huan Feng, Tapos Kumar Chakraborty, Yu Qian, Shinjae Yoo Nov 2025

Source Apportionment And Potential Health Risks Of Trace Metals In A Contaminated Urban River In New York/New Jersey Harbor System, Md Shahnul Islam, Sana Mirza, Huan Feng, Tapos Kumar Chakraborty, Yu Qian, Shinjae Yoo

Department of Earth and Environmental Studies Faculty Scholarship and Creative Works

The Lower Passaic River (LPR), located within the New York/New Jersey Harbor Estuarine System, has experienced long-term industrial activities, resulting in elevated concentrations of trace metals in sediment and water. This study aims to assess the bioaccumulation behavior, potential human health risks, and sources of copper (Cu), lead (Pb), and mercury (Hg) in the LPR. Trace metal concentrations were measured in water, sediment, and seven edible aquatic species. Data were analyzed using statistical approaches, and evaluated by bioaccumulation factors (BAFs) and human health risk assessments based on U.S. Environmental Protection Agency (USEPA) guidelines. Results showed that Hg exhibited the highest …


Spatially Mapped Statewide Estimated Potential Evapotranspiration Using An Efficient Surface Interpolation Method: A Case Study Of South Carolina, Sudhanshu S. Panda, Devendra M. Amatya, Ka Kit Liu, Augustine Muwamba, Timothy J. Callahan Nov 2025

Spatially Mapped Statewide Estimated Potential Evapotranspiration Using An Efficient Surface Interpolation Method: A Case Study Of South Carolina, Sudhanshu S. Panda, Devendra M. Amatya, Ka Kit Liu, Augustine Muwamba, Timothy J. Callahan

Journal of South Carolina Water Resources

Potential evapotranspiration (PET) exhibits substantial spatial and temporal variability across large landscapes, necessitating site-specific estimation for accurate environmental and water resource assessments. However, obtaining PET or ET data for specific locations across an entire state remains challenging due to the limited number of weather stations and associated environmental datasets. This study aimed to develop an automated geospatial modeling framework to map PET distribution across South Carolina, USA, using PET estimated by the temperature-based Hargreaves–Samani (H–S) method with daily weather data from 59 NOAA stations. Because the accuracy of spatial interpolation depends on both the target variable and the desired spatial …


Seagrass Persistence In The Indian River Lagoon And Lake Worth Lagoon, Florida, Kelly Kibler, Melinda Donnelly, Vincent Encomio, Madison Giuntoli, Manisha Thenuwara, Brice Bennett, Laura Andrade Barron, Mariam Sonbol, Wynter Raine Seppala, Namritha Ramakrishnan, Jennifer Jordan Báez, Beth Orlando, Irene Arpayoglou, Melissa Meisenburg Nov 2025

Seagrass Persistence In The Indian River Lagoon And Lake Worth Lagoon, Florida, Kelly Kibler, Melinda Donnelly, Vincent Encomio, Madison Giuntoli, Manisha Thenuwara, Brice Bennett, Laura Andrade Barron, Mariam Sonbol, Wynter Raine Seppala, Namritha Ramakrishnan, Jennifer Jordan Báez, Beth Orlando, Irene Arpayoglou, Melissa Meisenburg

Indian River Lagoon Shorelines

The spatial dataset: UCF_seagrasspersistence_IRL_LWL.shp was created with support from the Indian River Lagoon National Estuaries Program and Florida Sea Grant. These projects cumulatively led to creation of a living shoreline restoration prioritization model and hydrodynamic habitat suitability models for 1,550 km (963 miles) of estuarine shorelines in Indian River Lagoon (IRL) and Lake Worth Lagoon (LWL). The dataset presented herein represents persistence of seagrass throughout waters of the IRL and LWL.


Locations Of Outfalls In The Indian River Lagoon And Lake Worth Lagoon, Florida, Kelly M. Kibler, Melinda J. Donnelly, Vincent Encomio, Madison Giuntoli, Manisha Thenuwara, Brice Bennett, Laura Andrade Barron, Mariam Sonbol, Wynter Raine Seppala, Namritha Ramakrishnan, Jennifer Jordan Báez, Beth Orlando, Irene Arpayoglou, Melissa Meisenburg Nov 2025

Locations Of Outfalls In The Indian River Lagoon And Lake Worth Lagoon, Florida, Kelly M. Kibler, Melinda J. Donnelly, Vincent Encomio, Madison Giuntoli, Manisha Thenuwara, Brice Bennett, Laura Andrade Barron, Mariam Sonbol, Wynter Raine Seppala, Namritha Ramakrishnan, Jennifer Jordan Báez, Beth Orlando, Irene Arpayoglou, Melissa Meisenburg

Indian River Lagoon Shorelines

The spatial dataset: UCF_Outfalls_IRL_LWL.shp was created under grants from the Indian River Lagoon National Estuaries Program and Florida Sea Grant. These projects cumulatively led to creation of a living shoreline restoration prioritization model and hydrodynamic habitat suitability models for 1,550 km (963 miles) of estuarine shorelines in Indian River Lagoon (IRL) and Lake Worth Lagoon (LWL).

The dataset presented here includes the location of outfalls identified throughout the study region and general characteristics of the shoreline where they were identified.


Properties Of Liquid Fe-Ni Alloys Under Planetary Core Conditions And Their Geophysical Implications, Sajin Satyal Nov 2025

Properties Of Liquid Fe-Ni Alloys Under Planetary Core Conditions And Their Geophysical Implications, Sajin Satyal

LSU Doctoral Dissertations

The composition of Earth’s core remains unsolved, yet it carries critical implications for planetary evolution, thermal history, magnetic fields, and habitability. Planetary models derived from seismological observations, such as the Preliminary Reference Earth Model (PREM), indicate that Earth’s core is significantly less dense than pure iron, implying the presence of light elements, including sulfur, carbon, hydrogen, oxygen, and silicon. However, the exact composition and distribution of these elements remain largely unknown. In constraining Earth’s core composition, the density and compressional wave velocity of iron-rich alloys are often compared with seismologically derived models. However, no single iron–light-element alloy can simultaneously reproduce …


New Evidence Of Mid-Pleistocene Glaciations In The French Jura Mountains Using Debris Flow Deposits And U/Th Dating Of Speleothems (Verneau Karst Network), Margot Vivier, Stéphane Jaillet, Eglantine Husson, Edwige Pons Branchu, Jean-Baptiste Charlier Nov 2025

New Evidence Of Mid-Pleistocene Glaciations In The French Jura Mountains Using Debris Flow Deposits And U/Th Dating Of Speleothems (Verneau Karst Network), Margot Vivier, Stéphane Jaillet, Eglantine Husson, Edwige Pons Branchu, Jean-Baptiste Charlier

International Journal of Speleology

We redefine the extent of former glaciers in the northern Jura Mountains through the study of endokarst deposits. Sedimentary deposits (pebbly debris flows, laminated clays, and allochthonous limestone blocks) and chemical deposits (speleothems) were identified and studied using three complementary approaches: (i) detailed geomorphological mapping, (ii) petrographic analysis, and (iii) U/Th-dating. In addition, a surface geomorphological analysis made it possible to calculate the minimum erosion time required for the formation of the sinkhole linked to the underground study site. The study site is the Dolois Chamber, an underground site upstream of the Verneau karst network (Doubs Department, France). The combined …


Spatio-Temporal Characterization Of Trace Metals Across The West Florida Shelf And During The Decline Of The North Atlantic Spring Bloom, Delfina Paola Navarro-Estrada Nov 2025

Spatio-Temporal Characterization Of Trace Metals Across The West Florida Shelf And During The Decline Of The North Atlantic Spring Bloom, Delfina Paola Navarro-Estrada

USF Tampa Graduate Theses and Dissertations

Phytoplankton in the marine environment require the trace metals manganese (Mn), iron (Fe), cobalt (Co), nickel (Ni), copper (Cu), zinc (Zn), and cadmium (Cd) to catalyze cellular processes driving photosynthesis, including macronutrient (nitrogen, phosphorus, and carbon) acquisition, light harvesting, and protection from oxidative stress. The high biological demand for these elements, coupled with their low concentrations in the ocean, can limit primary production and shape community composition in marine ecosystems, highlighting the need to understand the drivers behind trace metal distributions and their interplay with phytoplankton growth across biogeochemical regimes. This dissertation characterizes the spatial and temporal distributions of dissolved …


Studies Of Seismicity In The Alaska Subduction Zone And Antarctica, Patrick Matulka Nov 2025

Studies Of Seismicity In The Alaska Subduction Zone And Antarctica, Patrick Matulka

Arts & Sciences Graduate Student Theses and Dissertations

This dissertation utilizes multiple methods of earthquake detection, relocation, and characterization to investigate the patterns of seismicity along the Alaska subduction zone and Antarctica. The studies of the Alaska subduction zone are built on the data collected during the Alaska Amphibious Community Seismic Experiment (AACSE) that deployed temporary land and ocean-bottom seismometers along the Alaska Peninsula and offshore regions from May 2018 to September 2019. Using seismic arrivals at those stations, as well as a combination of other land-based networks, I relocated 1307 earthquakes in the incoming plate and trench slope regions of the Alaska subduction zone with an absolute …


Shaping The Soil: A Comparison Of Equine, Bovine, And Ungrazed Hay Fields, Brody Ellis Higgs, Taylor Madison Wynn, Scottie Craig Berry Nov 2025

Shaping The Soil: A Comparison Of Equine, Bovine, And Ungrazed Hay Fields, Brody Ellis Higgs, Taylor Madison Wynn, Scottie Craig Berry

Scholars Week

Shaping the Soil: A Comparison of Equine, Bovine, and Ungrazed Hay Fields

Brody Higgs, Taylor Wynn, and Scottie Berry

Mentor: Dr. Iin. P. Handayani, PhD.

Hutson School of Agriculture, Murray State University, Murray, Kentucky, USA

ABSTRACT

Kentucky raises grazing species for multiple reasons, including food, recreation, and show. The most common of them are equine and bovine. These animals graze many acres across the state of Kentucky and impact soil properties in their pastures. This study was conducted on three pasturelands across Caldwell and Calloway counties in Kentucky. The pastures consisted of a cow pasture, a horse pasture, and a …


Uas Vs. In-Situ Measurement Techniques For Stream Substrates, Nathan Watson Nov 2025

Uas Vs. In-Situ Measurement Techniques For Stream Substrates, Nathan Watson

Scholars Week

UAS vs. In-situ Measurement Techniques for Stream Substrates

Key words: Geomorphic, Fluvial, ArcGIS Pro, UAS

Traditionally, geomorphic assessments of streams and fluvial structures have been conducted using in-situ field techniques. These techniques include taking Wolman (D50) pebble counts to characterize substrate, measurements of stream dimensions with tape, meter sticks, and Jacob staff. We studied the efficacy of using an uncrewed aerial system (UAS) to measure the substrate composition of a section of stream along the east fork of the Clarks River in Calloway County, Kentucky. The section consists of a 30-meter riffle-pool-run sequence, with variation in substrate size to test …


Exploiting Chloride Conservative Tendencies As Contaminant Surrogates In Groundwater Transport Modeling In A Typical Hydrogeological Environment Of Northern New Jersey, Toritseju Oyen, Duke Ophori Nov 2025

Exploiting Chloride Conservative Tendencies As Contaminant Surrogates In Groundwater Transport Modeling In A Typical Hydrogeological Environment Of Northern New Jersey, Toritseju Oyen, Duke Ophori

Department of Earth and Environmental Studies Faculty Scholarship and Creative Works

This study investigates the transport of chloride, a conservative tracer and surrogate for contaminants, in the fractured Brunswick aquifer of northern New Jersey using a dual-porosity MODFLOW-MT3DMS model. Focusing on the First Watchung Mountain region—a microcosm of northern New Jersey’s hydrogeological environment encompassing Montclair State University and adjoining communities, the numerical model simulates groundwater flow and solute transport in a hydrogeologically complex, urbanized setting. Results indicate that chloride migrates through the fractured aquifer via both local flow systems (e.g., Third River) and regional flow systems (Passaic River) within decades. Chloride concentrations exceeded the EPA’s 250 mg/L threshold much faster in …


Advancing Environmental Monitoring At Verde River Headwaters State Park Through Integrated Remote Sensing Technologies, Ronny Schroeder, Noah Morales, Colton Weeks, Reiner Zimmermann, Erika Podest, Hank Vincent Nov 2025

Advancing Environmental Monitoring At Verde River Headwaters State Park Through Integrated Remote Sensing Technologies, Ronny Schroeder, Noah Morales, Colton Weeks, Reiner Zimmermann, Erika Podest, Hank Vincent

Sustainability Conference

The establishment of Verde River Headwaters State Park in Chino Valley, Arizona, marks a significant conservation milestone with the acquisition of 734 acres of the historic Del Rio Springs Ranch by the Trust for Public Land in March 2024. Now under the stewardship of Arizona State Parks & Trails (ASPT), this site encompasses Sullivan Lake, Del Rio Springs, critical riparian habitats, and historically significant landmarks including the 1863 Arizona territorial capital and 1920s Fred Harvey Farm structures. This initiative yields substantial benefits, including annual water savings within the Prescott Active Management Area, the extension of the Peavine National Recreation Trail, …