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An Understanding Of The Feeding Ecology Of Teleoceras Fossiger And Teleoceras Aepysoma Using Dental Microwear And Mesowear Analysis, Gabriel S. Goncalves

Master's Theses or Doctor of Nursing Practice

Teleoceras is a genus of rhinocerotids that belongs to the Tribe Teleoceratines and was widespread across North America from the late Early Miocene into the Early Pliocene. This genus was very successful, spreading across the continental United States from Florida and Tennessee to California and Washington state down to central Mexico and Honduras. Teleoceras is characterized by having a large, rounded chest cavity and short limbs with relatively high crowned teeth and lower incisors modified into tusk-like teeth. Initial ecological comparisons were made to the modern hippopotamus based on proportions of the chest cavity and its hypsodont dentition. Stable carbon …

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 …

Horizontal Infiltration Of Water Through Porous Snow As A Gravity Current, Anthony Cheng

Dartmouth College Master’s Theses

On the surface of the Greenland ice sheet or around the margins of the Antarctic ice shelf, water infiltrates porous ice. It is important to understand this infiltration process since water populating the pore space of ice directly impacts the density, porosity, and wetness of ice. These properties influence the mechanics and tensile strength of ice, as greater amounts of infiltration result in faster or more widespread deformation events, which may lead to adverse climatic effects such as sea level rise and ocean current disruption. While studies have considered the thermodynamics and fluid mechanics of water vertically percolating through snow …

Quantifying Landscape Variability Of Dynamic Soil Properties In The James River Valley, Eastern South Dakota, Sage Reuter-Schmitt

Electronic Theses and Dissertations

Dynamic soil properties (DSP) are a great tool for monitoring land-use change, and they are frequently used as soil health metrics. The NRCS and other soil researchers often use repeating, single-point or nested-point DSP studies to monitor and better understand the effects of land management decisions. While these studies capture the temporal variability of DSPs, they overlook the field-scale spatial variability of DSPs. Soil organic carbon (SOC) provides critical services to the ecosystem and other environments. These traits, as well as its susceptibility to management decisions, make SOC an important soil health indicator and DSP. Measuring SOC is often time …

The Spatial And Temporal Dimensions Of Plant–Soil Feedback In Native Perennial Monocultures, Bret Lang

Electronic Theses and Dissertations

Plant-soil feedbacks (PSFs) describe how plants change their soil environment in ways that can either negatively or positively affect subsequent plant growth. In doing so, they offer an opportunity to connect ecological processes with agricultural practice. My dissertation examines PSFs created by native perennial monocultures, commonly used for native seed production, across time and space, and through soil legacies. Specifically, I focus on how plant species identity shapes both soil nutrient and soil microbial community responses. To address these questions, I conducted field experiments with monocultures of five forb species native to South Dakota and established plots with these species …

Proximal Seismic Tracking Of Pyroclastic Density Currents At Volcán De Fuego, Guatemala, Jacob A. Krier

Dissertations, Master's Theses and Master's Reports

Pyroclastic Density Currents (PDCs) are deadly flows of ash, tephra, gas, and solidified magma which predominantly occur when an ash plume collapses during a volcanic eruption. PDCs are also able to form when large deposits of ash at the summit of a volcano are displaced during an eruption and flow downslope. This is typically the mechanism behind PDCs that occur at Volcán de Fuego such as one that occurred in 2018 killing at least 430 people. The purpose of this paper is to track the propagation of PDCs that occurred at Fuego seismologically in order to better understand how they …

A Seismological Investigation Of Ground Deformation From Meteotsunami And Seiche Activity On Lake Michigan, Bryan Lowney

Dissertations, Master's Theses and Master's Reports

The mechanisms behind the formation and propagation of meteotsunamis and seiches—anomalous water waves generated by meteorological events that share similar spatial, temporal, and behavioral characteristics with seismically-generated tsunamis—are poorly understood. Small-scale ground tilt (microradians-nanoradians) triggered by these anomalous water waves in Lake Michigan is investigated with an array of 10 near-shore (< 100 km) seismometers installed from 2012-2014 by calculating tilt from seismic recordings and comparing it with data from relatively nearby (10s of km) NOAA water level stations in Holland and Ludington, Michigan. After determining an appropriate period band from 15 minutes to four days to isolate these events, we show that potential meteotsunami and seiche activity on eastern Lake Michigan can be deduced from long-term trends (multiple weeks) in tilt and water level time series. Exploratory in nature, the methods and observations presented in this paper serve as an initial step in quantifying the potential for nearshore seismometers to monitor shoreline inundation. Integrating these observations with meteorological data could provide insights into the origins of these hazards by linking them to the specific weather events that generated them. This approach offers a novel method for improving the understanding and potential future mitigation of meteotsunami and seiche impacts in the Great Lakes region.

Old, Flat, And Slow: Interior Greenland Snow And Ice Dynamics Revealed With Gnss, Derek James Pickell

Dartmouth College Ph.D Dissertations

The interior dry snow zone region of the Greenland Ice Sheet can no longer be confidently considered a reliably melt-free region, yet our ability to investigate and quantify the dynamic nature of this landscape is hindered by its remoteness. To overcome this challenge, this work describes a novel, low-cost, low-power GNSS (positioning) instrument that enables simultaneous measurements of (1) ice accumulation/ablation changes and (2) 3D ice flow. Deployed in a dense array, these GNSS instruments achieve similar performance to scientific-grade, commercial options (cm- to mm- precision), yet operate at < 60% of the power and < 34% of the hardware cost. Over a three year campaign, we analyze spatial and temporal patterns of accumulation in this region, using a technique called GNSS interferometric reflectometry (GNSS-IR). Observations with this technique show low bias and high precision relative to a validation study (-2.1 ± 2.9 cm), while we also demonstrate for the first time how GNSS-IR can reveal cm- to m- scale surface roughness, a critical yet often neglected measurement due to longstanding observational challenges. Patterns of accumulation show a spatial dependence linked to surface slope (~+0.7 mm w.e. km^-1 westward away from the divide) while surface roughness has a temporal dependence likely driven by wintertime high winds. Next, we combine GNSS-IR surface heights with the geodetic position time series of the antenna to derive surface elevation changes, which are compared to coincident ICESat-2 laser altimetry elevations. Observations of the surface show a millimeter-level relative bias and cm-level precision (-0.9 ± 3.8 cm) compared with the satellite altimeter, demonstrating for the first time that this technique is a viable ground-truthing method, while ICESat-2 performance has continued to exceed mission performance requirements. Finally, we examine station positioning through time to show a sensitivity to dynamic ice thinning and firn densification, two parameters than cannot be finely observed with space-based methods in this region. Together, these results provide the first ground‑based, high‑resolution picture of interior ice‑sheet change—capturing accumulation, roughness, surface elevation, and strain in one unified dataset. Our approach dramatically lowers logistical barriers, opening the interior of Greenland (and other remote regions) to sustained, quantitative monitoring at unprecedented spatiotemporal resolution.

Surface Currents In The Mid-Atlantic Bight: The Role Of The Gulf Stream Versus Wind, Tal Ezer

CCPO Publications

Surface currents of the Mid-Atlantic Bight (MAB) were studied using high frequency radar (HFR) observations at 6 km resolution during a five-year period (2020-2024). The study's focus on the role of the Gulf Stream (GS) contrasts with most past studies that focused on the seasonal wind-driven currents. Empirical Orthogonal Function (EOF) analyses of the daily HFR currents were conducted with and without the GS, revealing modes of current variability linked to the seasonal wind pattern and storms versus modes linked to GS variability. The remote impact of the GS on coastal currents is complex, with different impacts seen on different …

Spatial Analysis Of Heavy Metal Enrichment In A Historic Appalachian Mining Stream, Eric M. Torres

Research and Creativity Symposium

This study examined the spatial distribution of heavy metals along the Levisa Fork and primary tributaries in Buchanan County, VA and Pike County, KY. Buchanan and Pike Counties have a long history of coal mining, a process known to release heavy metals into surrounding waterways. Exposure to certain heavy metals, such as arsenic and lead, has been known to cause health problems, such as cancer and organ damage. The study looked at concentrations in riverine sediments, surface water and groundwater for As, Al, Cr, Cu, Fe, Li, Mg, Mn, Ni, Pb and Zn. Sediment samples were collected, dried and digested …

Investigating The Thermal Stratification Patterns Of A Shallow Polymictic Boreal Shield Lake And The Effectiveness Of Models In Predicting Shallow Lake Thermal Profiles, Matthew Roberts

Theses and Dissertations (Comprehensive)

Thermal stratification is a core process of lakes which plays a critical role in shaping the ecological dynamics of lakes, influencing major processes like nutrient cycling and oxygen availability. For shallow polymictic lakes, thermal stratification patterns present some unique differences due to the complex and variable nature of these lakes. In this thesis, I examined thermal stratification in a shallow polymictic lake in northwestern Ontario during the ice-free season of 2019 to investigate the frequency, duration, and driving factors of thermal stratification. The lake underwent 146 separate stratification events, with a median duration of 2 hours per event, with a …

Global Patterns Of Coseismic Landslide Runout Mobility Differ From Aseismic Landslide Trends, Alex R. R. Grant, Natalie K. Culhane

Geology Faculty Publications and Presentations

Coseismic landslides significantly contribute to human and economic losses during and immediately following earthquakes, yet very little data on the runout of such landslides exist. While well-established behavior of aseismic (e.g., hydrologically triggered) landslide runout mobility suggests strong correlation between landslide size and mobility, limited studies of coseismic landslide runout find conflicting mobility trends. We present a global dataset of runout lengths produced from a new automated method for estimating landslide runout, developed and validated using 1726 manually mapped landslides from five unique earthquakes. We then apply the automated runout tool to 23 global earthquake-induced landslide inventories, producing a compiled …

The Geography Of Rock Glaciers In The American West, Allison Reese Trcka, Andrew G. Fountain, Bryce Allen Glenn

Geology Faculty Publications and Presentations

Rock glaciers are relatively common in conterminous United States west of the 100° meridian, yet their distribution and number are not well known. Using aerial and satellite imagery, we inventoried the population of rock glaciers, yielding 2,257 rock glaciers totaling 234.28 km² with an area of uncertainty of 7 percent. Of these, 1,561 (155.44 km²) are considered intact (moving) and 696 (76.84 km²) relict. Based on published estimates of ice content, total water-equivalent volume is roughly 2.52 km³. Rock glacier elevations increase from the northwest (Washington) to the southeast (Colorado), following a spatial …

Investigating Heterogeneity Of Hydraulic Conductivity And Its Influence On Groundwater Flow Dynamics Within A Saturated Riparian Buffer In Central Illinois, Joseph L. Awuku

Theses and Dissertations

The use of Saturated Riparian Buffers (SRBs) in agricultural settings as a means of reducing contamination of surface water and groundwater resources has gained popularity due to their trapping ability and solute removal (nutrient recycling) capacity. In light of SRB’s nutrient-trapping and removal ability, numerous studies have been conducted to characterize the effectiveness of SRBs. However, most studies on SRBs have paid minimal attention to heterogeneity of hydraulic conductivity (K) and groundwater flow dynamics within SRBs. This study investigated the heterogeneity in horizontal K and estimated the vertical groundwater-specific discharge (q_v) between the upper weathered and its …

Carbon Dynamics Across The Mangrove-Tidal Flat Ecotone In A Tropical Seascape, E. S. Yando, I. J.B. Alemu, L. Kiah Eng, T. M. Sloey, M. Van Breugel, Bhatia N. Friess

Biological Sciences Faculty Publications

Mangroves and other blue carbon ecosystems are important for climate through the storage and sequestration of carbon. Most research estimates carbon dynamics by subsampling central portions of the ecosystem and are then upscales using habitat maps to patch, landscape, or regional levels. However, heterogeneity is rarely accounted for - particularly at edges. Further, adjacent tidal flat ecosystems have only recently been considered for carbon storage, but may be undervalued if areas where they transition with vegetated systems are not accounted for. To address the lack of information at coastal ecotones, we examined both soil carbon storage and carbon dioxide flux …

Assessing Potential For Managed Aquifer Recharge On The Manastash Alluvial Fan: A Geochemical Analysis, Elif A. Myers

All Master's Theses

In south-central Washington, the Yakima River Basin spans 6,100 square miles, encompassing approximately 10% of the state. With a growing population and over 400,000 acres of irrigated cropland, reliable water availability is vital for supporting agricultural irrigation, municipal needs, and aquatic habitats. To ensure water for future use, Managed Aquifer Recharge (MAR), the practice of applying surface water to aquifers for storage or hydrologic system benefit, has been proposed within the Yakima Basin Integrated Plan (YBIP). This research explores the Manastash alluvial fan–located west of Ellensburg, Washington as a potential region for two MAR methods: Shallow Aquifer Recharge (SAR) and …

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 …

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 …

Using Simulated Cascadia Fakequakes To Interpret Paleotsunami Patterns, Anthony M. Joyce

All Master's Theses

This study uses GeoClaw to simulate 8 instantaneous rupture test earthquakes and 48 stochastic earthquakes (Fakequakes) along the Cascadia Subduction Zone to better understand tsunami generation and propagation. The primary goal is to evaluate how variations in Fakequake rupture patterns affect tsunami heights at coastal sites in the Pacific Northwest. The study focused on comparing inner and outer coast wave heights and impacts to understand how the Olympic Peninsula provides a barrier of protection to inner coast sites from southern-generated tsunamis, and implications for tsunami hazard at Naval Air Station Whidbey Island (NASWI).

Test earthquakes show increased amounts of slip …

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. …

The Use Of Lidar In The Study Of Terrain Ruggedness Of Tsunami Inudation Areas At Grewingk Lake And Taan Fiord, Alaska Usa, Shannon P. Mckinnion

All Master's Theses

ABSTRACT

THE USE OF LIDAR IN THE STUDY OF TERRAIN RUGGEDNESS OF TSUNAMI INUDATION AREAS AT GREWINGK LAKE AND TAAN FIORD, ALASKA USA

by

Shannon Patricia McKinnion

In order to test the hypothesis that lidar technologies can detect possible changes in terrain ruggedness due tsunami inundation within a designated area, digital elevation models (DEM) were generated from lidar data for two sites with known tsunami inundation— Grewingk Lake, Alaska and Taan Fiord, Alaska. Cobbles and boulders in these locations were examined using existing terrain ruggedness tools in ArcHydro— Terrain Ruggedness Index (TRI) and Vector Ruggedness Measurement (VRM). The average values …

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 …

Seismic Constraints On Long Period Moment Release In Cascadia Slow Slip Events, Jordan M. Pentzer

All Master's Theses

Non-volcanic tremor, a low-amplitude, 1-5 Hz long-duration seismic noise signal easily resolvable by short-period seismometers of the Pacific Northwest Seismic Network, is the canonical seismic signature observed during Cascadia Episodic Tremor and Slip (ETS) Events. Whether significant energy is released at periods longer than 1 Hz has not been systematically searched for but nonetheless may exist and if so, could represent both a significant portion of the Cascadia moment budget as well as a mechanism by which slow slip and regular seismicity interact. The August 2010 ETS event beneath Puget Sound was well-recorded by a wide range of instruments that …

Impacts Of Southern Pine Beetle (Dendroctonus Frontalis Zimmerman) On Loblolly Pine (Pinus Taeda L.) Canopy And Water Use In The Homochitto National Forest, Mississippi, Usa, Sasha Goodnow, Yun Yang, Hui Liu, Ashley Schulz

Endeavors: Mississippi State Undergraduate Research Journal

Abiotic and biotic forest disturbances can have many impacts to forest ecosystem services, including to forest water use. Studies on impacts to forest evapotranspiration have been conducted on the mountain pine beetle (Dendroctonus ponderosae) in western North America, but not on the southern pine beetle (Dendroctonus frontalis), which is a native pest of loblolly pine (Pinus taeda) and shortleaf pine (Pinus echinata), in the southeastern United States. Stressed pine trees produce pheromones that attract southern pine beetles and, with enough stressed trees, beetle populations can quickly grow to epidemic levels and attack healthy trees, which results in widespread tree mortality. …

Assessment Of Rainfall Anomaly In Thailand Under Enso By Inception Time For Classification Model, Hazlamee Benjawong

Chulalongkorn University Theses and Dissertations (Chula ETD)

This study provides a comprehensive assessment of rainfall over Thailand during the El Niño-Southern Oscillation (ENSO) event using 41 years of monthly data (1982-2022) from meteorological stations, including total rainfall, average temperature, average wind speed, and average wind direction. The data were processed using Python by estimating spatially dependent monthly variables using inverse distance weighting. Total rainfall during ENSO events lasting more than two years was estimated by calculating ZSI12and analyzing the variable's significance using an inception time for classification model. The spatial total rainfall estimation results show that the distribution of total rainfall for normal, El Niño, and La …

Evaluation Of Soil Erosion In The Middle Yom River Basin, Passapong Paentong

Chulalongkorn University Theses and Dissertations (Chula ETD)

This study aims to assess soil erosion in the Middle Yom River Basin and analyze the spatial relationships between erosion and its influencing factors using the Revised Universal Soil Loss Equation (RUSLE) in combination with Ordinary Least Squares (OLS) regression analysis. The analysis considers five principal RUSLE factors: rainfall erosivity (R), soil erodibility (K), topography (LS), cover management (C), and support practices (P), under both normal and heavy rainfall scenarios for the years 2010, 2015, and 2020. The results indicate that under normal rainfall conditions, most areas experienced low to moderate soil loss (0–5 tons/rai/year). Under heavy rainfall conditions, the …

Gravity And Magnetic Analysis Of The Amu Darya Basin Of Turkmenistan And Uzbekistan, Logan R. Rogers

Graduate Theses/Dissertations

The Jurassic-Tertiary Amu Darya Basin is mainly located within Turkmenistan and Uzbekistan with a small portion extending into Afghanistan and Iran. The basin is one of the largest petroleum systems in central Asia. The basin is located in the southeast corner of the Turan platform, where both the Middle Paleozoic Turkestan and Early Mesozoic Tethys oceans were closed during different orogenies. The southern boundary of the basin is along the Bande Turkestan fold belt, the Afghan-Tajik basin to the east, Paleozoic metamorphic terranes to the north, and the Karakum high (Paleozoic basement rocks) to the west. Several blocks and terranes …

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 …

Critical Mineral Exploration In The Superior Province Of Northwestern Minnesota - A Geophysical Data Analysis, Michell L. Waterman

Graduate Theses/Dissertations

The Archean basement geology of northwest Minnesota, a region covered by glacial deposits and historically underexplored for minerals, was analyzed using gravity, magnetic, radiometric, and geochemical data. These datasets were integrated to aid in identifying subsurface structures and evaluating the area's potential for economic mineralization within the Wabigoon, Quetico, and Wawa Subprovinces of the Superior Province. Gravity and magnetic datasets, analyzed through upward continuation, derivative maps, and two-dimensional modeling, revealed distinct northeast-to-southwest-trending maxima corresponding to fault-bounded, high-density, and magnetically susceptible bodies. These features were interpreted as mafic to ultramafic intrusions and dikes, several of which align with known Proterozoic fault …

Integrated Valuation Of The Ecological, Social And Economic Benefits Provided By A Multifunctional Nature-Based Solution, Laura Costadone, Shan Zhang

ODU Articles

Nature-based Solutions (NbS) offer multifunctional approaches to address climate change and environmental challenges, providing a sustainable alternative to traditional gray infrastructure. Despite their promise, widespread adoption remains limited, in part due to an incomplete understanding of their full costs and benefits relative to conventional infrastructure. Traditional benefit–cost analyses often overlook non-monetized benefits and the interconnected ecosystem services provided by NbS. This study introduces a methodological approach to quantify both the physical and monetary value of ecosystem services and co-benefits delivered by an NbS project. We applied an integrated valuation framework to a case study in Virginia Beach, VA, USA, where …